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Oct 272015
 

 

Photo: N Palmer/CIAT

GCP sowed the seeds of a genetic resources revolution.

“In the last 10 years we have had a revolution in terms of developing the genetic resources of crops.”

So says Pooran Gaur, Principal Scientist for chickpea genetics and breeding at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), and Product Delivery Coordinator for chickpeas for the CGIAR Generation Challenge Programme (GCP).

He attributes this revolution in large part to GCP, saying it “played the role of catalyst. It got things started. It set the foundation. Now we are in a position to do further molecular breeding in chickpeas.”

Led by Pooran, researchers from India, Ethiopia and Kenya worked together not only to develop improved, drought-tolerant chickpeas that would thrive in semiarid conditions, but also to ensure these varieties would be growing in farmers’ fields across Africa within a decade.

The 10-year Generation Challenge Programme, with the goal of improving food security in developing countries, aimed to leave plant genetic assets as an important part of its legacy.

Diagnostic, or informative, molecular markers – which act like ‘tags’ for beneficial genes scientists are looking for – are an increasingly important genetic tool for breeders in developing resilient, improved varieties, and have been a key aspect of GCP’s research.

Photo: ICARDA

Chickpeas, ready to harvest.

What is a diagnostic molecular marker?

Developments in plant genetics over the past 10–15 years have provided breeders with powerful tools to detect beneficial traits of plants much more quickly than ever before.

Scientists can identify individual genes and explore which ones are responsible for, or contribute to, valuable characteristics such as tolerance to drought or poor soils, or resistance to pests or diseases.

Once a favourable gene for a target agronomic trait is discovered and located in the plant’s genome, the next step is to find a molecular marker that will effectively tag it. A molecular marker is simply a variation in the plant’s DNA sequence that can be detected by scientists using any of a range of methods. When one of these genetic variants is found close on the genome to a gene of interest (or even within the gene itself), it can be used to indicate the gene’s presence.

To use an analogy, think of a story as the plant’s genome: its words are the plant’s genes, and a molecular marker works like a text highlighter. Molecular markers are not precise enough to highlight specific words (genes), but they can highlight sentences (genomic regions) that contain these words, making it easier and quicker to identify whether or not they are present.

Once a marker is found to be associated with a gene, or multiple genes, and determined to be significant to a target trait, it is designated an informative marker, diagnostic marker or predictive marker. Some simple traits such as flower colour are controlled by one gene, but more complex traits such as drought tolerance are controlled by multiple genes. Diagnostic markers enable plant breeders to practise molecular breeding.

Breeders use markers to predict plant traits

Photo: N Palmer/CIAT

Hard work: a Ugandan bean farmer’s jembe, or hoe.

In the process known as marker-assisted selection, plant breeders use diagnostic molecular markers early in the breeding process to determine whether plants they are developing will have the desired qualities. By testing only a small amount of seed or seedling tissue, breeders are able to choose the best parent plants for crossing, and easily see which of the progeny have inherited useful genes. This considerably shortens the time it takes to develop new crop varieties.

“We use diagnostic markers to check for favourable genes in plants under selection. If the genes are present, we grow the seed or plant and observe how the genes are expressed as plant characteristics in the field [phenotyping]; if the genes are not present, we throw the seed or plant away,” explains Steve Beebe, a leading bean breeder with the International Center for Tropical Agriculture (CIAT) and GCP’s Product Delivery Coordinator for beans.

“This saves us resources and time, as instead of a growing few thousand plants to maturity, most of which would not possess the gene, by using markers to make our selection we need to grow and phenotype only a few hundred plants which we know have the desired genes.”

GCP supported 25 projects to discover and develop markers for genes that control traits that enable key crops, including bean and chickpea, to tolerate drought and poor soils and resist pests and diseases.

Genomic resources, including genetic maps and genotyping datasets, were developed during GCP’s first phase (2004–2008) and were then used in molecular-breeding projects during the second five years of the Programme (2009–2014).

“GCP’s philosophy was that we have, in breeding programmes, genomic resources that can be utilised. Now we are well placed, and we should be able to continue even after GCP with our molecular-breeding programme,” says Pooran.

Photo: IRRI

A small selection of the rice diversity in the International Rice Research Institute gene bank – raw material for the creation of genomic resources.

Markers developed for drought tolerance

Photo: N Palmer/CIAT

Cracked earth.

With climate change making droughts more frequent and severe, breeding for drought tolerance was a key priority for GCP from its inception.

Different plants may use similar strategies to tolerate drought, for example, having longer roots or reducing water loss from leaves. But drought tolerance is a complex trait to breed, as in each crop a large number of genes are involved.

Wheat, for example, has many traits – each controlled by different genes – that allow the crop to tolerate extreme temperature and/or lack of moisture. Identifying drought tolerance in wheat is therefore a search for many genes. In the particular case of wheat, this search is compounded by its genetic make-up, which is one of the most complex in the plant kingdom.

The difficulty of identifying genes that play a significant role in drought tolerance makes it all the more impressive when researchers successfully collaborate to overcome these challenges. GCP-supported scientists were able to develop and use diagnostic markers in chickpea, rice, sorghum and wheat to breed for drought tolerance. The first new drought-tolerant varieties bred using marker-assisted selection have already been released to farmers in Africa and Asia and are making significant contributions to food and income security.

Photo: ICRISAT

Tanzanian sorghum farmer.

Markers developed for pests and diseases

Photo: IITA

A bumper harvest of cassava roots at the International Institute of Tropical Agriculture (IITA) in Nigeria.

Cassava mosaic disease (CMD) is the biggest threat to cassava production in Africa – where more cassava is grown and eaten than any other crop. A principal source of CMD resistance is CMD2, a dominant gene that confers high levels of resistance.

Nigerian GCP-supported researchers worked on identifying and validating diagnostic markers that are associated with CMD2. These markers are being used in marker-assisted selection work to transfer CMD resistance to locally-adapted, farmer-preferred varieties.

In the common bean, GCP-supported researchers identified genes for resistance to pests such as bean stem maggot in Ethiopia, as well as diseases such as the common mosaic necrosis potyvirus and common bacterial blight, which reduce bean quality and yields and in some cases means total crop losses.

Markers developed for acidic and saline soils

Photo: N Palmer/CIAT

Sifting rice in Nepal.

Aluminium toxicity and phosphorus deficiency, caused by imbalanced nutrient availability in acid soils, are major factors in inhibiting crop productivity throughout the world. Aluminium toxicity also exacerbates the effects of drought by inhibiting root growth.

Diagnostic markers for genes that confer tolerance to high levels of aluminium and improve phosphorus uptake were identified in sorghum, maize and rice. The markers linked to these two sets of similar major genes have been used efficiently in breeding programmes in Africa and Asia.

Salt stress is also a major constraint across many rice-producing areas, partly because modern rice varieties are highly sensitive to salinity. Farmers in salt-affected areas have therefore continued growing their traditional crop varieties, which are more resilient but give low yields with poor grain quality. To address this issue, GCP supported work to develop and use markers to develop popular Bangladeshi varieties with higher tolerance to salt. GCP also funded several PhD students working in this area, one of whom was Armin Bhuiya.

Markers mean information, which means power

Diagnostic molecular markers are, in their most essential form, data. That means they are easily stored and maintained as data in publicly accessible databases and publications. Breeders can now access the molecular markers developed for various crops through the Integrated Breeding Platform – a web-based one-stop shop for integrated breeding information (including genetic resources), tools and support, which was established by GCP and is now continuing independently following GCP’s close – in order to design and carry out breeding projects.

“We could not have done that much in developing genomic resources without GCP support,” says Pooran. “Now the breeding products are coming; the markers are strengthening our work; and you will see in the next five to six years more products coming from molecular breeding.

“For me, GCP has improved the efficiency of the breeding programme – that is the biggest advantage.”

More links

Photo: N Palmer/CIAT

Beans on sale in Uganda.

Oct 162015
 
Photo: A Paul-Bossuet/ICRISAT

Pigeonpea farmers in India.

The tagline of the CGIAR Generation Challenge Programme (GCP) is ‘Partnerships in modern crop breeding for food security’. One of GCP’s many rewarding partnerships was with the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT).

The Institute was a source of valuable partnerships with highly regarded agricultural scientists and researchers, as well as of germplasm and genetic resources from its gene bank. With assistance from GCP, these resources have enabled scientists and crop breeders throughout Africa, Asia and Latin America to achieve crop improvements for chickpea, groundnut, pearl millet, pigeonpea and sorghum, all of which are staple crops that millions of people depend upon for survival.

“The philosophy of GCP at the start was to tap into and use the genomic recourses we had in our gene banks to develop ICRISAT’s and our partners’ breeding programmes,” says Pooran Gaur, GCP’s Product Delivery Coordinator for chickpeas, and Principal Scientist for chickpea genetics and breeding at ICRISAT.

ICRISAT’s gene bank is a global repository of crop genetic diversity. It contains 123,023 germplasm accessions – in the form of seed samples – assembled from 144 countries, making it one of the largest gene banks in the world.

The collection serves as insurance against genetic loss and as a source of resistance to diseases and pests, tolerance to climatic and other environmental stresses, and improved quality and yield traits for crop breeding.

Pooran says the ultimate goal of the GCP–ICRISAT partnership was to use the resources in the gene bank to develop drought-tolerant varieties that would thrive in semi-arid conditions and to make these varieties available to farmers’ fields within a decade.

Photo: S Kilungu/CCAFS

Harvesting sorghum in Kenya.

Setting a foundation for higher yielding, drought-tolerant chickpeas

Pooran was involved with GCP from its beginning in 2004 and was instrumental in coordinating chickpea projects.

Photo: ICRISAT

Chickpea harvest, India.

“GCP got things started; it set a foundation for using genomic resources to breed chickpeas,” says Pooran. During Phase I of GCP (2004–2009), ICRISAT was involved in developing reference sets for chickpeas and developing mapping populations for drought-tolerance traits. It also collaborated with 19 other international research organisations to successfully sequence the chickpea genome in 2013 – a major breakthrough that paved the way for the development of even more superior chickpea varieties to transform production in semi-arid environments.

The International Chickpea Genome Sequencing Consortium, led by ICRISAT and partly funded by GCP, identified more than 28,000 genes and several million genetic markers. Pooran says these are expected to illuminate important genetic traits that may enhance new varieties.

The trait of most interest to many chickpea breeders is drought tolerance. In recent years, droughts in the south of India, the largest producer of chickpeas, have reduced yields to less than one tonne per hectare. Droughts have also diminished chickpea yields in Ethiopia and Kenya, Africa’s largest chickpea producers and exporters to India. While total global production of chickpeas is around 8.6 million tonnes per year, drought causes losses of around 3.7 million tonnes worldwide.

Photo: ICRISAT

Putting it to the test: Rajeev Varshney (left, see below) and Pooran Gaur (right) inspecting a chickpea field trial.

Pooran says the foundation work supported by GCP was particularly important for identifying drought-tolerance traits. “We had identified plants with early maturing traits. This allowed us to develop chickpea varieties that have more chance of escaping drought when cereal farmers produce a fast-growing crop in between the harvest and planting of their main crops,” he says.

New varieties that grow and develop more quickly are expected to play a key role in expanding the area suitable for chickpeas into new niches where the available crop-growing seasons are shorter.

“In southern India now we are already seeing these varieties growing well, and their yield is very high,” says Pooran. “In fact, productivity has increased in the south by about seven to eight times in the last 10–12 years.”

Developing capacity by involving partners in Kenya and Ethiopia

Photo: GCP

Monitoring the water use of chickpea plants in experiments at Egerton University, Njoro, Kenya.

As part of GCP’s Tropical Legumes I project (TLI), incorporated within its Legume Research Initiative (RI), ICRISAT partnered with Egerton University in Kenya and the Ethiopian Institute of Agricultural Research (EIAR) to share breeding skills and resources to produce higher yielding, drought-tolerant chickpea varieties.

“When we first started working on this project in mid-2007, our breeding programme was very weak,” says Paul Kimurto of the Faculty of Agriculture at Egerton University, who was Lead Scientist for chickpea research in the TLI project. “We have since accumulated a lot of germplasm, a chickpea reference set and a mapping population, all of which have greatly boosted our breeding programme.”

Paul says that with this increased capacity, his team in Kenya had released six new varieties of chickpea in the five years prior to GCP’s close at the end of 2014, and were expecting more to be ready within in the next three years.

In fields across Ethiopia, meanwhile, the introduction of new varieties has already brought a dramatic increase in productivity, with yields doubling in recent years, according to Asnake Fikre, Crop Research Directorate Director for EIAR.

Varieties like the large-seeded and high-valued kabuli have presented new opportunities for farmers to earn extra income through the export industry, and indeed chickpea exports from eastern Africa have substantially increased since 2001. This has transformed Ethiopia’s chickpeas from simple subsistence crop to one of great commercial significance.

Photo: S Sridharan/ICRISAT

This chickpea seller in Ethiopia says that kabuli varieties are becoming more popular.

Decoding pigeonpea genome

Two years prior to the decoding of the chickpea genome, GCP’s Director Jean-Marcel Ribaut announced that a six-year, GCP-funded collaboration led by ICRISAT had already sequenced almost three-quarters of the pigeonpea genome.

“This will have significant impact on resource-poor communities in the semi-arid regions, because they will have the opportunity to improve their livelihoods and increase food availability,” Jean-Marcel stated in January 2012.

Pigeonpea, the grains of which make a highly nutritious and protein-rich food, is a hardy and drought-tolerant crop. It is grown in the semi-arid tropics and subtropics of Asia, Africa, the Americas and the Caribbean. This crop’s prolific seed production and tolerance to drought help reduce farmers’ vulnerability to potential food shortages during dry periods.

Photo: B Sreeram/ICRISAT

A pigeonpea farmer in his field in India.

The collaborative project brought together 12 participating institutes operating under the umbrella of the International Initiative for Pigeonpea Genomics. The initiative was led by Rajeev K Varshney, GCP’s Genomics Theme Leader and Director of the Center of Excellence in Genomics at ICRISAT. Other participants included BGI in Shenzhen, China; four universities; and five other advanced research entities, both private and public. The Plant Genome Research Program of the National Science Foundation, USA, also funded part of this research.

“We were able to assemble over 70 percent of the genome. This was sufficient to enable us to change breeding approaches for pigeonpea,” says Rajeev. “That is, we can now combine conventional and molecular breeding methods – something we couldn’t do as well before – and access enough genes to create many new pigeonpea varieties that will effectively help improve the food security and livelihoods of resource-poor communities.”

Pigeonpea breeders are now able to use markers for genetic mapping and trait identification, marker-assisted selection, marker-assisted recurrent selection and genomic selection. These techniques, Rajeev says, “considerably cut breeding time by doing away with several cropping cycles. This means new varieties reach dryland areas of Africa and Asia more quickly, thus improving and increasing the sustainability of food production systems in these regions.”

Several genes, unique to pigeonpea, were also identified for drought tolerance by the project. Future research may find ways of transferring these genes to other legumes in the same family – such as soybean, cowpea and common bean – helping these crops also become more drought tolerant. This would be a significant asset in view of the increasingly drier climates in these crops’ production areas.

“We cannot help but agree with William Dar, Director General of ICRISAT, who observed that the ‘mapping of the pigeonpea genome is a breakthrough that could not have come at a better time’,” says Jean-Marcel.

Photo: ICRISAT

East African farmers inspect pigeonpea at flowering time.

Securing income-generating groundnut crops in Africa

Groundnut, otherwise known as peanut, is one of ICRISAT’s mandate crops. Groundnuts provide a key source of nutrition for Africa’s farming families and have the potential to sustain a strong African export industry in future.

“The groundnut is one of the most important income-generating crops for my country and other countries in East Africa,” says Patrick Okori, who is a groundnut breeder and Principal Scientist with ICRISAT in Malawi and who was GCP’s Product Delivery Coordinator for groundnuts.

“It’s like a small bank for many smallholder farmers, one that can be easily converted into cash, fetching the highest prices,” he says

It is the same in West Africa, according to groundnut breeder Issa Faye from the Institut Sénégalais de Recherches Agricoles (ISRA), who has been involved in GCP since 2008. “It’s very important for Senegal,” he says. “It’s the most important cash crop here – a big source of revenue for farmers around the country. Senegal is one of the largest exporters of groundnut in West Africa.”

In April 2014, the genomes of the groundnut’s two wild ancestral parents were successfully sequenced by the International Peanut Genome Initiative – a multinational group of crop geneticists, including those from ICRISAT, who had been working in collaboration for several years.

The sequencing work has given breeders access to 96 percent of all groundnut genes and provided the molecular map needed to breed drought-tolerant and disease-resistant higher yielding varieties, faster.

Photo: S Sridharan/ICRISAT

Drying groundnut harvest, Mozambique.

“The wild relatives of a number of crops contain genetic stocks that hold the most promise to overcome drought and disease,” says Vincent Vadez, ICRISAT Principal Scientist and groundnut research leader for GCP’s Legumes Research Initiative. And for groundnut, these stocks have already had a major impact in generating the genetic tools that are key to making more rapid and efficient progress in crop science

Chair of GCP’s Consortium Committee, David Hoisington – formerly ICRISAT’s Director of Research and now Senior Research Scientist and Program Director at the University of Georgia – says the sequencing could be a huge step forward for boosting agriculture in developing countries.

“Researchers and plant breeders now have much better tools available to breed more productive and more resilient groundnut varieties, with improved yields and better nutrition,” he says.

These resilient varieties should be available to farmers across Africa within a few years.

Supporting key crops in West Africa

Photo: N Palmer/CIAT

Harvested pearl millet and sorghum in Ghana.

With a focus on the semi-arid tropics, ICRISAT has been working closely with partners for 30 years to improve rainfed farming systems in West Africa. One sorghum researcher who has been working on the ground with local partners in Mali since 1998 is Eva Weltzien-Rattunde. She is an ICRISAT Principal Scientist in sorghum breeding and genetic resources, based in Mali, and was Principal Investigator for GCP’s Sorghum Research Initiative.

Eva and her team collaborated with local researchers at Mali’s Institut d’Economie Rurale (IER) and France’s Centre de coopération internationale en recherche agronomique pour le développement (CIRAD; Agricultural Research for Development) on a project to test a novel molecular-breeding approach: backcross nested association mapping (BCNAM). Eva says this method has the potential to halve the time it takes to develop local sorghum varieties with improved yield and adaptability to poor soil fertility conditions.

In another project, under GCP’s Comparative Genomics Research Initiative, Eva and her team are using molecular markers developed through the RI to select for aluminium-tolerant and phosphorus-efficient varieties and validating their performance in field trials across 29 environments in three countries in West Africa.

“Low phosphorus availability is a key problem for farmers on the coast of West Africa, and breeding phosphorus-efficient crops to cope with these conditions has been a main objective of ICRISAT in West Africa for some time,” says Eva.

“We’ve had good results in terms of field trials. We have at least 20 lines we are field testing at the moment, which we selected from 1,100 lines that we tested under high and low phosphorous conditions.” Eva says that some of these lines could be released as new varieties as early as 2015.

Ibrahima Sissoko, a data curator working with Eva’s team at ICRISAT in Mali, also adds that the collaborations and involvement with GCP have increased his and other developing country partners’ capacity in data management and statistical analysis, as well as helping to expand their network. “I can get help from other members of my sorghum community,” he says.

In summing up, Eva says: “Overall, we feel the GCP partnerships are enhancing our capacity here in Mali, and that we are closer to delivering more robust sorghum varieties that will help farmers and feed the ever-growing population in West Africa.”

Photo: A Paul-Bossuet/ICRISAT

Enjoying a tasty dish of sorghum.

Tom Hash, millet breeder and Principal Scientist at ICRISAT and GCP Principal Investigator for millet, shares Eva’s sentiments on GCP and the impact it is having in West Africa.

Between 2005 and 2007, GCP invested in genetic research for millet, which is the sixth most important cereal crop globally and a staple food (along with sorghum) in Burkina Faso, Chad, Eritrea, Mali, Niger, northern Nigeria, Senegal and Sudan.

With financial support from GCP, and drawing on lessons learnt from parallel GCP genetic research, including in sorghum and chickpea, ICRISAT was able to mine its considerable pearl millet genetic resources for desirable traits.

Hari D Upadhyaya, Principal Scientist and Head of Genebank at ICRISAT in India, led this task to develop and genotype a ‘composite collection’ of pearl millet. The team created a selection that strategically reduced the 21,594 accessions in the gene bank down to just 1,021. This collection includes lines developed at ICRISAT and material from other sources, with a range of valuable traits including tolerance to drought, heat and soil salinity and resistance to blast, downy mildew, ergot, rust and smut, and even resistance to multiple diseases.

The team then used molecular markers to fingerprint the DNA of plants grown from the collection.

“GCP supported collaboration with CIRAD, and our pearl millet breeding teams learnt how to do marker-based genetic diversity analysis,” says Tom. “This work, combined with the genomic resources work, did make some significant contributions to pearl millet research.”

Over 100 new varieties of pearl millet have recently been developed and released in Africa by the African Centre for Crop Improvement in South Africa, another developing country partner of ICRISAT and GCP. Tom says the initial genetic research was pivotal to this happening.

Photo: N Palmer/CIAT

A Ghanaian farmer examines his pearl millet harvest.

From poverty to prosperity through partnerships

Patrick Okori says that GCP has enabled his organisation to make a much stronger contribution to the quality of science.

“Prior to GCP, ICRISAT was already one of the big investors in legume research, because that was its mandate. The arrival of GCP, however, expanded the number of partners that ICRISAT had, both locally and globally, through the resources, strategic meetings and partnership arrangements that GCP provided as a broad platform for engaging in genomic research and the life sciences.”

This expansion of ICRISAT, facilitated by GCP, also enabled researchers from across the world and in diverse fields to interact in ways they had never had the opportunity to before, says Vincent Vadez.

“GCP has allowed me to make contact with people working on other legumes, for example,” he says. “It has allowed us to test hypotheses in other related crops, and we’ve generated quite a bit of good science from that.”

Pooran Gaur has had a similar experience with his chickpea research at ICRISAT.

“GCP provided the first opportunity for us to work with the bean and cowpea groups, learning from each other. That cross-learning from other crops really helped us. You learn many things working together, and I think we have developed a good relationship, a good community for legumes now.”

This community environment has made the best use of an unusual variety of skills, knowledge and resources, agrees Rajeev Varshney.

“It brought together people from all kinds of scientific disciplines – from genomics, bioinformatics, biology, molecular biology and so on,” he says. “Such a pooling of complementary expertise and resources made great achievements possible.”

More links

Photo: A Paul-Bossuet/ICRISAT

Man and beast team up to transport chickpeas in Ethiopia.

 

Oct 122015
 

 

Photo: One Acre Fund/Flickr (Creative Commons)

A Kenyan farmer harvesting her maize.

“The map of Kenya’s maize-growing regions mirrors the map of the nation’s acid soils.”

So says Dickson Ligeyo, senior research officer at the Kenya Agricultural and Livestock Research Organisation (KALRO; formerly the Kenya Agricultural Research Institute, or KARI), who believes this paints a sombre picture for his country’s maize farmers.

Maize is a staple crop for Kenyans, with 90 percent of the population depending on it for food. However, acid soils cause yield losses of 17–50 percent across the nation.

Soil acidity is a major environmental and economic concern in many more countries around the world. The availability of nutrients in soil is affected by pH, so acid conditions make it harder for plants to get a balanced diet. High acidity causes two major problems: perilously low levels of phosphorus and toxically high levels of aluminium. Aluminium toxicity affects 38 percent of farmland in Southeast Asia, 31 percent in Latin America and 20 percent in East Asia, sub-Saharan Africa and North America.

Aluminium toxicity in soil comes close to rivalling drought as a food-security threat in critical tropical food-producing regions. By damaging roots, acid soils deprive plants of the nutrients and water they need to grow – a particularly bitter effect when water is scarce.

Maize, meanwhile, is one of the most economically important food crops worldwide. It is grown in virtually every country in the world, and it is a staple food for more than 1.2 billion people in developing countries across sub-Saharan Africa and Latin America. In many cultures it is consumed primarily as porridge: polenta in Italy; angu in Brazil; and isitshwala, nshima, pap, posho,sadza or ugali in Africa.

Photo: Allison Mickel/Flickr (Creative Commons)

Ugali, a stiff maize porridge that is a staple dish across East Africa, being prepared in Tanzania.

Maize is also a staple food for animals reared for meat, eggs and dairy products. Around 60 percent of global maize production is used for animal feed.

The world demand for maize is increasing at the same time as global populations burgeon and climate changes. Therefore, improving the ability of maize to withstand acid soils and produce higher yields with less reliable rainfall is paramount. This is why the CGIAR Generation Challenge Programme (GCP) invested almost USD 12.5 million into maize research between 2004 and 2014.

GCP’s goal was to facilitate the use of genetic diversity and advanced plant science to improve food security in developing countries through the breeding of ‘super’ crops – including maize – able to tolerate drought and poor soils and resist diseases.

 By weight, more maize is produced each year than any other grain: global production is more than 850 million tonnes. Maize production is increasing at twice the annual rate of rice and three times that of wheat. In 2020, demand for maize in developing countries alone is expected to exceed 500 million tonnes and will surpass the demand for both rice and wheat.  This projected rapid increase in demand is mainly because maize is the grain of choice to feed animals being reared for meet – but it is placing strain on the supply of maize for poor human consumers. Demand for maize as feed for poultry and pigs is growing, particularly in East and Southeast Asia, as an ever-increasing number of people in Asia consume meat. In some areas of Asia, maize is already displacing sorghum and rice. Acreage allocated to maize production in South and Southeast Asia has been expanding by 2.2 percent annually since 2001. In its processed form, maize is also used for biofuel (ethanol), and the starch and sugars from maize end up in beer, ice cream, syrup, shoe polish, glue, fireworks, ink, batteries, mustard, cosmetics, aspirin and paint.

Researchers take on the double whammy of acid soils and drought

Part of successfully breeding higher-yielding drought-tolerant maize varieties involves improving plant genetics for acid soils. In these soils, aluminium toxicity inhibits root growth, reducing the amount of water and nutrients that the plant can absorb and compounding the effects of drought.

Improving plant root development for aluminium tolerance and phosphorous efficiency can therefore have the positive side effect of higher plant yield when water is limited.

Photo: A Wangalachi/CIMMYT

A farmer in Tanzania shows the effects of drought on her maize crop. The maize ears are undersized with few grains.

Although plant breeders have exploited the considerable variation in aluminium tolerance between different maize varieties for many years, aluminium toxicity has been a significant but poorly understood component of plant genetics. It is a particularly complex trait in maize that involves multiple genes and physiological mechanisms.

The solution is to take stock of what maize germplasm is available worldwide, characterise it, clone the sought-after genes and implement new breeding methods to increase diversity and genetic stocks.

Scientists join hands to unravel maize complexity

Scientists from the International Maize and Wheat Improvement Center (CIMMYT) and the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) got their heads together between 2005 and 2008 to itemise what maize stocks were available.

Marilyn Warburton, then a molecular geneticist at CIMMYT, led this GCP-funded project. Her goal was to discover how all the genetic diversity in maize gene-bank collections around the globe might be used for practical plant improvement. She first gathered samples from gene banks all over the world, including those of CIMMYT and the International Institute of Tropical Agriculture (IITA). Scientists from developing country research centres in China, India, Indonesia, Kenya, Nigeria, Thailand and Vietnam also contributed by supplying DNA from their local varieties.

Photo: X Fonseca/CIMMYT

Maize diversity.

Researchers then used molecular markers and a bulk fingerprinting method – which Marilyn was instrumental in developing – for three purposes: to characterise the structure of maize populations, to better understand how maize migrated across the world, and to complete the global picture of maize biodiversity. Scientists were also using markers to search for new genes associated with desirable traits.

Allen Oppong, a maize pathologist and breeder from Ghana’s Crops Research Institute (CRI), of the Council for Scientific and Industrial Research, was supported by GCP from 2007 to 2010 to characterise Ghana’s maize germplasm. Trained in using the fingerprinting technique, Allen was able to identify distinctly different maize germplasm in the north of Ghana (with its dry savanna landscape) and in the south (with its high rainfall). He also identified mixed germplasm, which he says demonstrates that plant germplasm often finds its way to places where it is not suitable for optimal yield and productivity. Maize yields across the country are low.

Stocktaking a world’s worth of maize for GCP was a challenge, but not the only one, according to Marilyn. “In the first year it was hard to see how all the different partners would work together. Data analysis and storage was the hardest; everyone seemed to have their own idea about how the data could be stored, accessed and analysed best.

“The science was also evolving, even as we were working, so you could choose one way to sequence or genotype your data, and before you were even done with the project, a better way would be available,” she recalls.

Photo: N Palmer/CIAT

Maize ears drying in Ghana.

Comparing genes: sorghum gene paves way for maize aluminium tolerance

In parallel to Marilyn’s work, scientists at the Brazilian Corporation of Agricultural Research (EMBRAPA) had already been advancing research on plant genetics for acid soils and the effects of aluminium toxicity on sorghum – spurred on by the fact that almost 70 percent of Brazil’s arable land is made up of acid soils.

What was of particular interest to GCP in 2004 was that the Brazilians, together with researchers at Cornell University in the USA, had recently mapped and identified the major sorghum aluminium tolerance locus AltSB, and were working on isolating the major gene within it with a view to cloning it. Major genes were known to control aluminium tolerance in sorghum, wheat and barley and produce good yields in soils that had high levels of aluminium. The gene had also been found in rape and rye.

GCP embraced the opportunity to fund more of this work with a view to speeding up the development of maize – as well as sorghum and rice – germplasm that can withstand the double whammy of acid soils and drought.

Photo: L Kochian

Maize trials in the field at EMBRAPA. The maize plants on the left are aluminium-tolerant and so able to withstand acid soils, while those on the right are not.

Leon Kochian, Director of the Robert W Holley Center for Agriculture and Health, United States Department of Agriculture – Agricultural Research Service and Professor at Cornell University, was a Principal Investigator for various GCP research projects investigating how to improve grain yields of crops grown in acid soils. “GCP was interested in our work because we were working with such critical crops,” he says.

“The idea was to use discoveries made in the first half of the GCP’s 10-year programme – use comparative genomics to look into genes of rice and maize to see if we can see relations in those genes – and once you’ve cloned a gene, it is easier to find a gene that can work for other crops.”

The intensity of GCP-supported maize research shifted up a gear in 2007, after the team led by Jurandir Magalhães, research scientist in molecular genetics and genomics of maize and sorghum at EMBRAPA, used positional cloning to identify the major sorghum aluminium tolerance gene SbMATE responsible for the AltSB aluminium tolerance locus. The team comprised researchers from EMBRAPA, Cornell, the Japan International Research Center for Agricultural Sciences (JIRCAS) and Moi University in Kenya.

By combing the maize genome searching for a similar gene to sorghum’s SbMATE, Jurandir’s EMBRAPA colleague Claudia Guimarães and a team of GCP-supported scientists discovered the maize aluminium tolerance gene ZmMATE1. High expression of this gene, first observed in maize lines with three copies of ZmMATE1, has been shown to increase aluminium tolerance.  ZmMATE1 improves grain yields in acid soil by up to one tonne per hectare when introgressed in an aluminium-sensitive line.

Photos: 1 – V Alves ; 2 – F Mendes; both edited by C Guimarães

The genetic region, or locus, containing the ZmMATE1 aluminium tolerance gene is known as qALT6. Photo 1 shows a rhyzobox containing two layers of soil: a corrected top-soil and lower soils with 15 percent aluminium saturation. On the right, near-isogenic lines (NILs) introgressed with qALT6 show deeper roots and longer secondary roots in the acidic lower soil, whereas on the left the maize line without qALT6, L53, shows roots mainly confined to the corrected top soil. Photo 2 shows maize ears from lines without qALT6 (above) and with qALT6 (below); the lines with qALT6 maintain their size and quality even under high aluminium levels of 40 percent aluminium saturation.

The outcomes of these GCP-supported research projects provided the basic materials, such as molecular markers and donor sources of the positive alleles, for molecular-breeding programmes focusing on improving maize production and stability on acid soils in Latin America, Africa and other developing regions.

Kenya deploys powerful maize genes

One of those researchers crucial to achieving impact in GCP’s work in maize was Samuel (Sam) Gudu of Moi University, Kenya. From 2010 he was the Principal Investigator for GCP’s project on using marker-assisted backcrossing (MABC) to improve aluminium tolerance and phosphorous efficiency in maize in Kenya. This project combined molecular and conventional breeding approaches to speed up the development of maize varieties adapted to the acid soils of Africa, and was closely connected to the other GCP comparative genomics projects in maize and sorghum.

MABC is a type of marker-assisted selection (see box), which Sam’s team – including Dickson Ligeyo of KALRO – used to combine new molecular materials developed through GCP with Kenyan varieties. They have thus been able to significantly advance the breeding of maize varieties suitable for soils in Kenya and other African countries.

Marker-assisted selection helps breeders like Sam Gudu more quickly develop plants that have desirable genes. When two plants are sexually crossed, both positive and negative traits are inherited. The ongoing process of selecting plants with more desirable traits and crossing them with other plants to transfer and combine such traits takes many years using conventional breeding techniques, as each generation of plants must be grown to maturity and phenotyped – that is, the observable characteristics of the plants must be measured to determine which plants might contain genes for valuable traits.   By using molecular markers that are known to be linked to useful genes such as ZmMATE1, breeders can easily test plant materials to see whether or not these genes are present. This helps them to select the best parent plants to use in their crosses, and accurately identify which of the progeny have inherited the gene or genes in question without having to grow them all to maturity. Marker-assisted selection therefore reduces the number of years it takes to breed plant varieties with desired traits.

Maize and Comparative Genomics were two of seven Research Initiatives (RIs) where GCP concentrated on advancing researchers’ and breeders’ skills and resources in developing countries. Through this work, scientists have been able to characterise maize germplasm using improved trait observation and characterisation methods (phenotyping), implement molecular-breeding programmes, enhance strategic data management and build local human and infrastructure capacity.

The ultimate goal of the international research collaboration on comparative genomics in maize was to improve maize yields grown on acidic soils under drought conditions in Kenya and other African countries, as well as in Latin America. Seven institutes partnered up to for the comparative genomics research: Moi University, KALRO, EMBRAPA, Cornell University, the United States Department of Agriculture (USDA), JIRCAS and the International Rice Research Institute (IRRI).

“Before funding by GCP, we were mainly working on maize to develop breeding products resistant to disease and with increased yield,” says Sam. “At that time we had not known that soil acidity was a major problem in the parts of Kenya where we grow maize and sorghum. GCP knew that soil acidity could limit yields, so in the work with GCP we managed to characterise most of our acid soils. We now know that it was one of the major problems for limiting the yield of maize and sorghum.

“The relationship to EMBRAPA and Cornell University is one of the most important links we have. We developed material much faster through our collaboration with our colleagues in the advanced labs. I can see that post-GCP we will still want to communicate and interact with our colleagues in Brazil and the USA to enable us to continue to identify molecular materials that we discover,” he says. Sam and other maize researchers across Kenya, including Dickson, have since developed inbred, hybrid and synthetic varieties with improved aluminium tolerance for acid soils, which are now available for African farmers.

Photo: N Palmer/CIAT

A Kenyan maize farmer.

“We crossed them [the new genes identified to have aluminium tolerance] with our local material to produce the materials we required for our conditions,” says Sam.

“The potential for aluminium-tolerant and phosphorous-efficient material across Africa is great. I know that in Ethiopia, aluminium toxicity from acid soil is a problem. It is also a major problem in Tanzania. It is a major problem in South Africa and a major problem in Kenya. So our breeding work, which is starting now to produce genetic materials that can be used directly, or could be developed even further in these other countries, is laying the foundation for maize improvement in acid soils.”

Sam is very proud of the work: “Several times I have felt accomplishment, because we identified material for Kenya for the first time. No one else was working on phosphorous efficiency or aluminium tolerance, and we have come up with materials that have been tested and have become varieties. It made me feel that we’re contributing to food security in Kenya.”

Photo: N Palmer/CIAT

Maize grain for sale.

Maize for meat: GCP’s advances in maize genetics help feed Asia’s new appetites

Reaping from the substantial advances in maize genetics and breeding, researchers in Asia were also able to enhance Asian maize genetic resources.

Photo: D Mowbray/CIMMYT

A pig roots among maize ears on a small farm in Nepal.

Bindiganavile Vivek, a senior maize breeder for CIMMYT based in India, has been working with GCP since 2008 on improving drought tolerance in maize, especially for Asia, for two reasons: unrelenting droughts and a staggering growth the importance of maize as a feedstock. This work was funded by GCP as part of its Maize Research Initiative.

“People’s diets across Asia changed after government policies changed in the 1990s. We had a more free market economy, and along with that came more money that people could spend. That prompted a shift towards a non vegetarian diet,” Vivek recounts.

“Maize, being the number one feed crop of the world, started to come into demand. From the year 2000 up to now, the growing area of maize across Asia has been increasing by about two percent every year. That’s a phenomenal increase. It’s been replacing other crops – sorghum and rice. There’s more and more demand.

“Seventy percent of the maize that is produced in Asia is used as feed. And 70 percent of that feed is poultry feed.”

In Vietnam, for example, the government is actively promoting the expansion of maize acreage, again displacing rice. Other Asian nations involved in the push for maize include China, Indonesia and The Philippines.

Photo: A Erlangga/CIFOR

A farmer in Indonesia transports his maize harvest by motorcycle.

The problem with this growth is that 80 percent of the 19 million hectares of maize in South and Southeast Asia relies on rain as its only source of water, so is prone to drought: “Wherever you are, you cannot escape drought,” says Vivek. And resource-poor farmers have limited access to improved maize products or hybrids appropriate for their situation.

Vivek’s research for GCP focused on the development – using marker-assisted breeding methods, specifically marker-assisted recurrent selection (MARS) – of new drought-tolerant maize adapted to many countries in Asia. His goal was to transfer the highest expression of drought tolerance in maize into elite well-adapted Asian lines targeted at drought-prone or water-constrained environments.

Asia’s existing maize varieties had no history of breeding for drought tolerance, only for disease resistance. To make a plant drought tolerant, many genes have to be incorporated into a new variety. So Vivek asked: “How do you address the increasing demand for maize that meets the drought-tolerance issue?”

The recent work on advancing maize genetics for acid soils in the African and Brazilian GCP projects meant it was a golden opportunity for Vivek to reap some of the new genetic resources.

“This was a good opportunity to use African germplasm, bring it into India and cross it to some Asia-adapted material,” he says.

Photo: E Phipps/CIMMYT

Stored maize ears hanging in long bunches outside a house in China.

A key issue Vivek faced, however, was that most African maize varieties are white, and most Asian maize varieties are yellow. “You cannot directly deploy what you breed in Africa into Asia,” Vivek says. “Plus, there’s so much difference in the environments [between Africa and Asia] and maize is very responsive to its environment.”

The advances in marker-assisted breeding since the inception of GCP contributed significantly towards the success of Vivek’s team.

“In collaboration with GCP, IITA, Cornell University and Monsanto, CIMMYT has initiated the largest public sector MARS breeding approach in the world,” says Vivek.

The outcome is good: “We now have some early-generation, yellow, drought-tolerant inbred germplasm and lines suitable for Asia.

“GCP gave us a good start. We now need to expand and build on this,” says Vivek.

GCP’s supported work laid the foundation for other CIMMYT projects, such as the Affordable, Accessible, Asian Drought-Tolerant Maize project funded by the Syngenta Foundation for Sustainable Agriculture. This project is developing yet more germplasm with drought tolerance.

A better picture: GCP brightens maize research

Dickson Ligeyo’s worries of a stormy future for Kenya’s maize production have lifted over the 10 years of GCP. At the end of 2014, Kenya had two new varieties that were in the final stage of testing in the national performance trials before being released to farmers.

“There is a brighter picture for Kenya’s maize production since we have acquired acid-tolerant germplasm from Brazil, which we are using in our breeding programmes,” Dickson says.

In West Africa, researchers are also revelling in the opportunity they have been given to help enhance local yields in the face of a changing climate. “My institute benefited from GCP not only in terms of human resource development, but also in provision of some basic equipment for field phenotyping and some laboratory equipment,” says Allen Oppong in Ghana.

“Through the support of GCP, I was able to characterise maize landraces found in Ghana using the bulk fingerprinting technique. This work has been published and I think it’s useful information for maize breeding in Ghana – and possibly other parts of the world.”

The main challenge now for breeders, according to Allen, is getting the new varieties out to farmers: “Most people don’t like change. The new varieties are higher yielding, disease resistant, nutritious – all good qualities. But the challenge is demonstrating to farmers that these materials are better than what they have.”

Photo: CIMMYT

This Kenyan farmer is very happy with his healthy maize crop, grown using an improved variety during a period of drought.

Certainly GCP has strengthened the capacity of researchers across Africa, Asia and Latin America, training researchers in maize breeding, data management, statistics, trial evaluations and phenotyping. The training has been geared so that scientists in developed countries can use genetic diversity and advanced plant science to improve crops for greater food security in the developing world.

Elliot Tembo, a maize breeder with the private sector in sub-Saharan Africa says: “As a breeder and a student, I have been exposed to new breeding tools through GCP. Before my involvement, I was literally blind in the use of molecular tools. Now, I am no longer relying only on pedigree data – which is not always reliable – to classify germplasm.”

Allen agrees: “GCP has had tremendous impact on my life as a researcher. The capacity-building programme supported my training in marker-assisted selection training at CIMMYT in Mexico. This training exposed me to modern techniques in plant breeding and genomics. Similarly, it built my confidence and work efficiency.”

There is no doubt that GCP research has brightened the picture for maize research and development where it is most needed: with researchers in developing countries where poor farmers and communities rely on maize as their staple food and main crop.

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Photo: N Palmer/CIAT

A farmer displays maize harvested on his farm in Laos.

Oct 012015
 

 

Photo: C. Schubert/CCAFS

A farmer from Dodoma, Tanzania, an area where climate change is causing increasing heat and drought. Groundnut is an important crop for local famers, forming the basis of their livelihood together with maize and livestock.

If you don’t live with poor people, then your science is of no use to poor people. This is the very clear sentiment of Omari Mponda, one of Tanzania’s top groundnut researchers.

“Sometimes people do rocket science. But that’s not going to help the poor,” says Omari. “Scientists in labs are very good at molecular markers, but markers by themselves will not address the productivity on the ground. You cannot remove poverty through that alone.”

Omari is the Zonal Research Coordinator and plant breeder at Tanzania’s Agricultural Research Institute at Naliendele (ARI–Naliendele).

The passion and dedication of Omari and his colleagues at this East African research centre were the reason why, between 2008 and 2014, the CGIAR Generation Challenge Programme (GCP) provided funding for legumes research at ARI–Naliendele that especially targeted drought, as part of the Tropical Legumes I project. This project supplied national institutes across Africa, Asia and Latin America with training and infrastructure improvements that enabled local researchers to do more advanced plant science that could make a real difference to farmers.

Researchers like Omari, who are working on the ground in developing countries, are a crucial part of the global quest to develop solutions for future food security and improved livelihoods in these countries.

GCP set out to enhance the plant-breeding skills and capacity of researchers in developing nations, such as Tanzania, so that they can develop their own crop varieties that will cope with increasingly extreme drought conditions.

Photo: C Schubert/CCAFS

A farmer in dryland Tanzania shows off his groundnut crop.

“One thing that really energises me,” enthuses GCP Consultant Hannibal Muhtar, “is seeing people understand why they need to do the work and being given the chance to do the how.”

Hannibal, under his GCP remit, was asked to visit the research sites of GCP-funded projects at research centres and stations across Africa, to identify those where effective research might be hindered by significant gaps in three fundamental areas: infrastructure, equipment and support services. He selected 19 target research sites – in Burkina Faso, Ethiopia, Ghana, Kenya, Mali, Niger, Nigeria and Tanzania.

Photo: AgCommons

Hannibal Muhtar (left) and Omari Mponda at ARI–Naliendele.

Two of the locations chosen for some practical empowerment were in Tanzania, namely the ARI research sites at Naliendele and Mtwara, where simple infrastructure improvements like irrigation tubing and portable weather stations have made a surprising difference to the capacity of local researchers.

In developing countries like Tanzania, the obstacles to achieving research objectives are often quite mundane in nature: a faulty weather station, the lack of irrigation systems, or fields ravaged by weeds and in dire need of rehabilitation. Yet such factors compromise brilliant research.

Even a simple lack of fencing commonly results not only in equipment being stolen, but also in precious experimental crops being stomped on by roaming cattle and wild animals such as boars, monkeys, hippopotamuses and hyenas; this also poses a serious threat to the safety of field staff.

“The real challenge lies not in the science, but rather in the real nuts and bolts of getting the work done in local field conditions,” Hannibal explains.

He says: “If GCP had not invested in research support infrastructure and services, then their investment in research would have been in vain. Tools and services must be in place as and when needed, and in good working order. Tractors must be able to plough when they should plough.”

Bridging the gap between the lab and farmers

Since 2008, researchers at ARI–Naliendele in Tanzania have been working together with the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) to identify suitable groundnut breeding materials to help the country’s farmers improve crop yields. Currently, yields are at less than one-third of their potential.

“We are bridging the big science to the poor people, to see the real issues we should be addressing. You can have a very good resistant variety, but maybe that variety is not liked by farmers,” Omari says.

He recalls a case where one farmer who helped with variety selection for international research had identified a groundnut variety that was resistant to disease, but the shells were too difficult to crack.

“So that variety won’t help the poor, because he [the farmer] is not able to open the shell. So the breeder had to rethink, what trait could loosen, or make it easier to shell?” recounts Omari.

Photo: N Palmer/CIAT

Shelled groundnuts on sale in Ghana.

The mission of the 10-year GCP was to use genetic diversity and advanced plant science to improve crops in developing countries. More than 200 partners were involved in the programme, including members of the international CGIAR group plus academia and regional and national research programmes.

National institutes like Tanzania’s ARI–Naliendele, established in 1970, are essential linchpins between advanced research centres in developed countries and poor farmers around the world facing the day-to-day realities of climate change and plant pests and diseases.

“If each organisation works in isolation, they will spend a lot of money developing new varieties but nothing will change on the ground. So in actually working together through programmes like the GCP, we can see some change happening,” says Omari.

Through the GCP project, Tanzania’s groundnut researchers received 300 reference-set lines from ICRISAT, which were then phenotyped over three years (2008–2010) for both drought tolerance and disease resistance in order to select the most useful lines under local conditions. To help with this process, Tanzanian scientists and technicians travelled to ICRISAT headquarters in India, where they were trained in phenotyping: that is, how to identify and measure observable characteristics – in this case, traits relating to the plants’ abilities to cope with drought and disease.

After the researchers identified the best varieties, these were provided to participating farmers so they could trial them in their fields for selection in 2011–2012. Five new varieties have since been released to Tanzanian farmers based on this collaboration between ARI and ICRISAT.

Photo: A Masciarelli/FAO

A young groundnut plant.

Things are speeding up in Tanzania

For ARI–Naliendele, the laboratory and field infrastructure provided by GCP funding has helped accelerate the work of local researchers and breeders. It has been transformative for Tanzanian scientists, according to Omari.

“For example, irrigation is very costly, but with the GCP support for an irrigation system, we can fast track our work – we can come up with new varieties in a much shorter period. That is something that will change our lives,” says Omari.

“Groundnut has a very low multiplication ratio, so if you plant one kilogram, you will get only 10 kilograms next year,” he explains. “Ten kilograms in 12 months is not enough. With irrigation, it means that we can have at least two or three crops within a season. Some of the varieties we are developing can be fast tracked to the end users. The speed of getting varieties from the research to the farmers has increased by maybe three times.”

Photo: D Brazier/IWMI

Washing harvested groundnuts, Zimbabwe.

GCP also funded computers, measuring scales, laboratory equipment and a portable weather station, which all help to assure good, reliable information on phenotyping.

Scientists too have become quicker and better at their work from having more advanced skills, according to Omari: “We now have more competent groundnut breeders in Tanzania.

“Initially, we depended on germplasm being brought over by ICRISAT and somebody selecting varieties for us. But they have been training us to do our own crosses, so we can now decide what grows in our breeding programme,” he says.

“For us, it is a big achievement to be able to do national crosses. We are advancing toward being a functional breeding programme in Tanzania.

“These gains made are not only sustainable, but also give us independence and autonomy to operate. We developing-country scientists are used to conventional breeding, but we now see the value and the need for adjusting ourselves to understand the use of molecular markers in groundnut breeding.”

Tanzania’s new zest for advanced plant breeding

Photo: N Palmer/CIAT

A farmer at work in her cassava field in northern Tanzania.

According to cassava breeder Geoffrey Mkamilo, a Principal Agricultural Research Officer at ARI: “There are some things that you just cannot do by conventional breeding.”

Usually researchers looking to breed better drought-tolerant and disease- and pest-resistant crops would use conventional breeding methods. This means researchers would be trying to pick out resilient plants by phenotyping alone, looking at how they are growing in the field under different conditions, which can take considerable time to deliver results – especially for crops that are slow to mature, like cassava.

Molecular breeding, on the other hand, involves using molecular markers to make the breeding process faster and more effective. These markers are genetic sequences known to be linked to useful genes that confer plant traits such as drought tolerance or disease resistance. Breeders can easily test small amounts of plant material for these markers, so they act like genetic ‘tags’, flagging up whether or not particular genes are present.

This knowledge helps breeders to efficiently select the best parent plants to use in their crosses, and accurately identify which of the progeny have inherited the gene or genes in question without having to grow them all to maturity. Phenotyping is still needed in discovering markers, linking genetic information with physical traits, and in testing the performance of materials in the field, but overall the time taken produce a new variety can be reduced by years.

“Before I started working with GCP, molecular breeding for me was very, very difficult… I wasn’t trained to become a molecular breeder. Now, with GCP, I can speak the same language,” Geoffrey says.

Photo: Kanju/IITA

A farmer carefully packs harvested cassava tubers for transportation to the market in Bungu, Tanzania.

Via GCP, Geoffrey had the opportunity to work with scientists based in Colombia at the International Center for Tropical Agriculture (CIAT) and in Nigeria at the International Institute of Tropical Agriculture (IITA), among other experts in research institutes across the world.

The team first began to release new cassava varieties developed using marker-assisted selection in 2011, with four varieties for two different Tanzanian environments. These varieties had manifold benefits: dual resistance to cassava mosaic disease (CMD) and cassava brown streak disease (CBSD), and productivity potential of up to double the yield of existing commercial varieties.

The research continues to produce ever better cassava varieties, and in this endeavour Geoffrey cannot overemphasise the power of integrating conventional breeding practices with molecular breeding.

“I have received so many phone calls from farmers; they even call in the night. They say, ‘Geoffrey, we have heard that you have very good materials. Where do we get these materials?’ So many, many farmers are calling,” says Geoffrey. “Many, many organisations – even NGOs, they also call. They want these materials. And even the private sector calls. GCP has contributed tremendously to this.”

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Sep 282015
 

 

Photo: Agência BrasíliaSorghum is already a drought-hardy crop, and is a critical food source across Africa’s harsh, semi-arid regions where water-intensive crops simply cannot survive. Now, as rainfall patterns become increasingly erratic and variable worldwide, scientists warn of the need to improve sorghum’s broad adaptability to drought.

Crop researchers across the world are now on the verge of doing just that. Through support from the CGIAR Generation Challenge Programme (GCP), advanced breeding methods are enhancing the capacity of African sorghum breeders to deliver more robust varieties that will help struggling farmers and feed millions of poor people across sub-Saharan Africa.

Photo: ICRISAT

A farmer in her sorghum field in Tanzania.

Sorghum at home in Africa

From Sudanese savannah to the Sahara’s desert fringes, sorghum thrives in a diverse range of environments. First domesticated in East Africa some 6000 years ago, it is well adapted to hot, dry climates and low soil fertility, although still depends on receiving some rainfall to grow and is very sensitive to flooding.

In developed countries such as Australia, sorghum is grown almost exclusively to make feed for cattle, pigs and poultry, but in many African countries millions of poor rural people directly depend on the crop in their day-to-day lives.

Photo: ICRISAT

A Malian woman and her child eating sorghum.

In countries like Mali sorghum is an important staple crop. It is eaten in many forms such as couscous or (a kind of thick porridge), it is used for making local beer, and its straw is a vital source of feed for livestock.

While the demand for, and total production of, sorghum has doubled in West Africa in the last 20 years, yields have generally remained low due to a number of causes, from drought and problematic soils, to pests and diseases.

“In Mali, for instance, the average grain yield for traditional varieties of sorghum has been less than one tonne per hectare,” says Eva Weltzein-Rattunde, Principal Scientist for Mali’s sorghum breeding programme at the International Crops Research Institute for the Semi-Arid-Tropics (ICRISAT).

In a continued quest to integrate ways to increase productivity, GCP launched its Sorghum Research Initiative (RI) in 2010. This aimed to investigate and apply the approaches by which genetics and molecular breeding could be used to improve sorghum yields through better adaptability, particularly in the drylands of West Africa where cropping areas are large and rainfall is becoming increasingly rare.

Kick starting the work was a GCP-funded collaboration between project Principal Investigator Niaba Témé, plant breeder at Mali’s Institut d’économie rurale (IER) and the RI’s Product Delivery Coordinator Jean-François Rami of the Centre de coopération internationale en recherche agronomique pour le développement (CIRAD; Agricultural Research for Development), France, with additional support from the Syngenta Foundation for Sustainable Agriculture in Switzerland.

The collaboration aimed to develop ways to improve sorghum’s productivity and adaptation in the Sudano-Sahelian zone, starting with Mali in West Africa, and expanding later across the continent to encompass Burkina Faso, Ethiopia, Kenya, Niger and Sudan.

Photo: F Noy/UN Photo

A farmer harvest sorghum in Sudan.

Sorghum gains from molecular research

Since 2008, with the help of CIRAD and Syngenta, Niaba and his team at IER have been learning how to use molecular markers to develop improved sorghum germplasm through identifying parental lines that are more tolerant and better adapted to the arid and volatile environments of Mali.

The two breeding methods used in the collaboration are known as marker-assisted recurrent selection (MARS) and backcross nested association mapping (BCNAM).

MARS

Photo: N Palmer/CIAT“MARS identifies regions of the genome that control important traits,” explains Jean-François. “It uses molecular markers to explore more combinations in the plant populations, and thus increases breeding efficiency.”

Syngenta, he explains, became involved through its long experience in implementing MARS in maize.

“Syngenta advised the team on how to conduct MARS and ways we could avoid critical pitfalls,” he says. “They gave us access to using the software they have developed for the analysis of data, and this enabled us to start the programme immediately.”

With the help of the IER team, two bi-parental populations from elite local varieties were developed, targeting two different environments found in sorghum cropping areas in Mali. “We were then able to use molecular markers through MARS to identify and monitor key regions of the genome in consecutive breeding generations,” says Jean-François.

“When we have identified the genome regions on which to focus, we cross the progenies and monitor the resulting new progenies,” he says. “The improved varieties subsequently go to plant breeders in Mali’s national research program, which will later release varieties to farmers.”

Jean-François is pleased with the success of the MARS project so far. “The development of MARS addressed a large range of breeding targets for sorghum in Mali, including adaptation to the environment and grain productivity, as well as grain quality, plant morphology and response to diseases,” he says. “It proved to be efficient in elucidating the complex relationships between the large number of traits that the breeder has to deal with, and translating this into target genetic ideotypes that can be constructed using molecular markers.”

Jean-François says several MARS breeding lines have already shown superior and stable performance in farm testing as compared to current elite lines, and these will be available to breeders in Mali in 2015 to develop new varieties.

Photo: ICRISAT

Eva Weltzein-Rattunde examines sorghum plants with farmers in Mali.

BCNAM

Like MARS, the BCNAM approach shows promise for being able to quickly gain improvements in sorghum yield and adaptability to drought, explains Niaba, who is Principal Investigator of the BCNAM project. BCNAM may be particularly effective, he says, in developing varieties that have the grain quality preferences of Malian farmers, as well as the drought tolerance that has until now been unavailable.

“BCNAM involves using an elite recurrent parent that is already adapted to local drought conditions, then crossing it with several different specific or donor parents to build up larger breeding populations,” he explains. “The benefit of this approach is it can lead to detecting elite varieties much faster.”

Eva and her team at ICRISAT have also been collaborating with researchers at IER and CIRAD on the BCNAM project. The approach, she says, has the potential to halve the time it takes to develop local sorghum varieties with improved yield and adaptability to poor soil fertility conditions.

“We don’t have these types of molecular-breeding resources available in Mali, so it’s really exciting to be a part of this project,” she says. “Overall, we feel the experience is enhancing our capacity here, and that we are closer to delivering more robust sorghum varieties which will help farmers and feed the ever-growing population in West Africa.”

Indeed, during field testing in Mali, BCNAM lines derived from the elite parent variety Grinkan have produced more than twice the yields of Grinkan itself. As they are rolled out in the form of new varieties, the team anticipates that they will have a huge positive impact on farmers’ livelihoods.

Photo: E Weltzein-Rattunde/ICRISAT

Malian sorghum farmers.

Mali and Queensland similar problem, different soil

In Mali and the wider Sahel region within West Africa, cropping conditions are ideal for sorghum. The climate is harsh, with daily temperatures on the dry, sun-scorched lower plains rarely falling below 30°C. With no major river system, the threat of drought is ever-present, and communities are entirely dependent on the 500 millimetres of rain that falls during the July and August wet season.

“All the planting and harvesting is done during the rainy season,” says Niaba. “We have lakes that are fed by the rain, but when these lakes start to dry up farmers rely mostly on the moisture remaining in the soil.”

Over 17 thousand kilometres to the east of Mali, in north-eastern Australia’s dryland cropping region, situated mainly in the state of Queensland, sorghum is the main summer crop, and is considered a good rotational crop as it performs well under heat and moisture stress. The environment here is similar to Mali’s, with extreme drought a big problem.

Average yields for sorghum in Queensland are double those in Mali—around two tonnes per hectare—yet growers still consider them low, directly limited by the crop’s predominantly water-stressed production environment in Australia.

One of the differentiating factors is soil. “Queensland has a much deeper and more fertile soil compared to Mali, where the soil is shallow, with no mulch or organic matter,” says Niaba. “Also, there is no management at the farm level in Mali, so when rain comes, if the soil cannot take it, we lose it.”

Photo: Bart Sedgwick/Flickr (Creative Commons)

Sorghum in Queensland, Australia.

Making sorghum stay green, longer

Another key reason for the difference in yields between Queensland and Mali is that growers in Queensland are sowing a sorghum variety of with a genetic trait that makes it more tolerant to drought.

This trait is called ‘stay-green’, and over the last two decades it has proven valuable in increasing sorghum yields, using less water, in north-eastern Australia and the southern United States.

Stay-green allows sorghum plants to stay alive and maintain green leaves for longer during post-flowering drought—that is, drought that occurs after the plant has flowered. This means the plants can keep growing and produce more grain in drier conditions.

“We’ve found that stay-green can improve yields by up to 30 percent in drought conditions with very little downside during a good year,” says Andrew Borrell from the Queensland Alliance for Agriculture and Food Innovation (QAAFI) at the University of Queensland (UQ) in Australia.

“Plant breeders have known about stay-green for some 30 years,” he says. “They’d walk their fields and see that the leaves of certain plants would remain green while others didn’t. They knew it was correlated with high yield under drought conditions, but didn’t know why.”

Stay-green’s potential in Mali

With their almost 20 years working on understanding how stay-green works, Andrew and his colleagues at UQ were invited by GCP in 2012 to take part in the IER/CIRAD collaborative project, to evaluate the potential for introducing stay-green into Mali’s local sorghum varieties and enriching Malian pre-breeding material for the trait.

A pivotal stage in this new alliance was a 12-month visit to Australia by Niaba and his IER colleague Sidi Coulibaly, to work with Andrew and his team to understand how stay-green drought resistance works in tall Malian sorghum varieties.

“African sorghum is very tall and sensitive to variation in day length,” explains Andrew. “We have been looking to investigate if the stay-green mechanism operates in tall African sorghums (around four metres tall) in the same way that it does in short Australian sorghum (one metre tall).”

Having just completed a series of experiments at the end of 2014, the UQ team consider their data as preliminary at this stage. “But it looks like we can get a correlation between stay-green and the size and yield of these Malian lines,” says Andrew. “We think it’s got great potential.”

Photo: S Sridharan/ICRISAT

Sorhum growing in Mozambique.

Sharing knowledge as well as germplasm

Eva Weltzein-Rattunde has played more of an on-the-ground capacity development role in Mali since accepting her position at ICRISAT in 1998. She says “the key challenges have been improving the infrastructure of the national research facilities [in Mali] to do the research as well as increasing the technical training for local agronomists and researchers.”

Photo: ICRISAT

A Malian farmer harvests Sorghum.

A large part of GCP’s focus is building just such capacity among developing country partners to carry out crop research and breeding independently in future, so they can continue developing new varieties with drought adaptation relevant to their own environmental conditions.

A key objective of the IER team’s Australian visit was to receive training in the methods for improving yields and drought resistance in sorghum breeding lines from both Australia and Mali.

“We learnt about association mapping, population genetics and diversity, molecular breeding, crop modelling using climate forecasts, and sorghum physiology, plus a lot more,” says Niaba. This training complemented previous training Niaba and IER researchers had from CIRAD and ICRISAT through the MARS and BCNAM projects.

“We [CIRAD] have a long collaboration in sorghum research in Mali and training young scientists has always been part of our mission,” says Jean-François. “We’ve hosted several IER students here in France and we are always interacting with our colleagues in Mali either over the phone or travelling to Mali to give technical workshops in molecular breeding.”

Photo: Rita Willaert/Flickr (Creative Commons)

Harvested sorghum in Sudan.

Working together to implement MARS in the sorghum breeding program in Mali represented many operational challenges, Jean-François explains. “The approach requires a very tight integration of different and complementary skills, including a strong conventional breeding capacity, accurate breeders’ knowledge, efficient genotyping technologies, and skills for efficient genetic analyses,” he says.

Because of this requirement, he adds, there are very few reported experiences of the successful implementation of MARS.  It is also the reason why these kinds of projects would normally not be undertaken in a developing country like Mali, but for the support of GCP and the dedicated mentorship of Jean-François.

sorghum quote 2“GCP provided the perfect environment to develop the MARS approach,” says Jean-François. “It brought together people with complementary skills, developed the Integrated Breeding Platform (IPB), and provided tools and services to support the programme.”

In addition to developing capacity, Jean-François says one of the great successes of both the MARS and the BCNAM projects was how they brought together Mali’s sorghum research groups working at IER and ICRISAT in a common effort to develop new genetic resources for sorghum breeding.

“This work has strengthened the IER and ICRISAT partnerships around a common resource. The large multiparent populations that have been developed are analysed collectively to decipher the genetic control of important traits for sorghum breeding in Mali,” says Jean-François. “This community development is another major achievement of the Sorghum Research Initiative.” The major challenge, he adds, will be whether this community can be kept together beyond GCP.

Considering the numerous ‘non-GCP’ activities that have already been initiated in Africa as a result of the partnerships forged through GCP research, Jean-François sees a clear indication that these connections will endure well beyond GCP’s time frame.

GCP’s sunset is Mali’s sunrise

Photo: S Sridharan/ICRISAT

Sorghum at sunset in Mozambique.

Among the new activities Jean-François lists are both regional and national projects aimed at building on what has already been achieved through GCP and linking national partners together. These include the West African Agricultural Productivity Program (WAAPP), the West Africa Platform being launched by CIRAD as a continuation of the MARS innovation, and another MARS project in Senegal and Niger through the Feed the Future Innovation Lab for Collaborative Research on Sorghum and Millet at Kansas State University.

“These are all activities which will help maintain the networks we’ve built,” Jean-François says. “I think it is very important that these networks of people with common objectives stick together.”

sorghum quoteFor Niaba, GCP provided the initial boost needed for these networks to emerge and thrive. “We had some contacts before, but we didn’t have the funds to really get into a collaboration. This has been made possible by GCP. Now we’re motivated and are making connections with other people on how we can continue working with the material we have developed.”

“I can’t talk enough of the positive stories from GCP,” he adds. “GCP initiated something, and the benefits for me and my country I cannot measure. Right now, GCP has reached its sunset; but for me it is a sunrise, because what we have been left with is so important.”

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Photo: ICRISAT

A sorghum farmer in her field in Tanzania.

Jun 222015
 
Photo: Joseph Hill/Flickr (Creative Commons)

Groundnut plants growing in Senegal.

Across Africa, governments and scientists alike are heralding groundnuts’ potential to lead resource-poor farmers out of poverty.

Around 5,000 years ago in the north of Argentina, two species of wild groundnuts got together to produce a natural hybrid. The result of this pairing is the groundnut grown today across the globe, particularly in Africa and Asia. Now, scientists are discovering the treasures hidden in the genes of these ancient ancestors.

Nearly half of the world’s groundnut growing area lies within the African continent, yet Africa’s production of the legume has, until recently, accounted for only 25 percent of global yield. Drought, pests, diseases and contamination are all culprits in reducing yields and quality. But through the CGIAR Generation Challenge Programme (GCP), scientists have been developing improved varieties using genes from the plant’s ancient ancestors. These new varieties are destined to make great strides towards alleviating poverty in some of the world’s most resource-poor countries.

Photo: Bill & Melinda Gates Foundation

A Ugandan farmer at work weeding her groundnut field.

A grounding in the history of Africa’s groundnuts

From simple bar snack in the west to staple food in developing countries, groundnuts – also commonly known as peanuts – have a place in the lives of many peoples across the world. First domesticated in the lush valleys of Paraguay, groundnuts have been successfully bred and cultivated for millennia. Today they form a billion-dollar industry in China, India and the USA, while also sustaining the livelihoods of millions of farming families across Africa and Asia.

Groundnut facts and figures •	About one-third of groundnuts produced globally are eaten and two-thirds are crushed for oil  •	The residue from oil processing is used as an animal feed and fertiliser •	Oils and solvents derived from groundnuts are used in medicines, textiles, cosmetics, nitro-glycerine, plastics, dyes, paints, varnishes, lubricating oils, leather dressings, furniture polish, insecticides and soap •	Groundnut shells are used to make plastic, wallboard, abrasives, fuel, cellulose and glue; they can also be converted to biodiesel

“The groundnut is one of the most important income-generating crops for my country and other countries in East Africa,” says Malawian groundnut breeder Patrick Okori, Principal Scientist at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), who was also GCP’s Product Delivery Coordinator for groundnuts.

“It’s like a small bank for many smallholder farmers, one that can be easily converted into cash, fetching the highest prices,” he says.

The situation is similar in West Africa, according to groundnut breeder Issa Faye from the Institut Sénégalais de Recherches Agricoles (ISRA; Senegalese Agricultural Research Institute), who has been involved in GCP since 2008. “It’s very important for Senegal,” he says. “It’s the most important cash crop here – a big source of revenue for farmers around the country. Senegal is one of the largest exporters of peanut in West Africa.”

Groundnuts have good potential for sustaining a strong African export industry in future, while providing a great source of nutrition for Africa’s regional farming families.

“We believe that by using what we have learnt through GCP, we will be able to boost the production and exportation of groundnuts from Senegal to European countries, and even to Asian countries,” says Issa. “So it’s very, very important for us.”

Photo: Joseph Hill/Flickr (Creative Commons)

Harvested groundnuts in Senegal.

How Africa lost its groundnut export market

Photo: V Vadez

Groundnuts in distress under drought conditions.

In Africa, groundnuts have mostly been grown by impoverished smallholder farmers, in infertile soils and dryland areas where rainfall is both low and erratic. Drought and disease cause about USD 500 million worth of losses to groundnut production in Africa every year.

“Because groundnut is self-pollinating, most of the time poor farmers can recycle the seed and keep growing it over and over,” Patrick says. “But for such a crop you need to refresh the seed frequently, and after a certain period you should cull it. So the absence of, or limited access to, improved seed for farmers is one of the big challenges we have. Because of this, productivity is generally less than 50 percent of what would be expected.”

Photo: S Sridharan/ICRISAT

Rosette virus damage to groundnut above and below ground.

Diseases such as the devastating groundnut rosette virus – which is only found in Africa and has been known to completely wipe out crops in some areas – as well as pests and preharvest seed contamination have all limited crop yields and quality and have subsequently shut out Africa’s groundnuts from export markets.

The biggest blow for Africa came in the 1980s from a carcinogenic fungal toxin known as aflatoxin, explains Patrick.

Photo: IITA

Aflatoxin-contaminated groundnut kernels from Mozambique.

Aflatoxin is produced by mould species of the genus Aspergillus, which can naturally occur in the soil in which groundnuts are grown. When the fungus infects the legume it produces a toxin which, if consumed in high enough quantities, can be fatal or cause cancer. Groundnut crops the world over are menaced by aflatoxin, but Africa lost its export market because of high contamination levels.

“That’s why a substantial focus of the GCP research programme has been to develop varieties of groundnuts with resistance to the fungus,” says Patrick.

After a decade of GCP support, a suite of new groundnut varieties representing a broad diversity of characteristics is expected to be rolled out in the next two or three years. This suite will provide a solid genetic base of resistance from which today’s best commercial varieties can be improved, so the levels of aflatoxin contamination in the field can ultimately be reduced.

Ancestral genes could hold the key to drought tolerance and disease resistance

In April 2014, the genomes of the groundnut’s two wild ancestral parents were successfully sequenced by the International Peanut Genome Initiative – a multinational group of crop geneticists, who had been working in collaboration for several years.

The sequencing work has given breeders access to 96 percent of all groundnut genes and provided the molecular map needed to breed drought-tolerant and disease-resistant higher-yielding varieties, faster.

“The wild relatives of a number of crops contain genetic stocks that hold the most promise to overcome drought and disease,” says Vincent Vadez, ICRISAT Principal Scientist and groundnut research leader for GCP’s Legumes Research Initiative. And for groundnut, these stocks have already had a major impact in generating the genetic tools that are key to making more rapid and efficient progress in crop breeding.

“Genetically, the groundnut has always been a really tough nut to crack,” says GCP collaborator David Bertioli, from the University of Brasilia in Brazil. “It has a complex genetic structure, narrow genetic diversity and a reputation for being slow and difficult to breed. Until its genome was sequenced, the groundnut was bred relatively blindly compared to other crops, so it has remained among the less studied crops,” he says.

With the successful genome sequencing, however, researchers can now understand groundnut breeding in ways they could only dream of before.

Photo: N Palmer/CIAT

Groundnut cracked.

“Working with a wild species allows you to bring in new versions of genes that are valuable for the crop, like disease resistance, and also other unexpected things, like improved yield under drought,” David says. “Even things like seed size can be altered this way, which you don’t really expect.”

The sequencing of the groundnut genome was funded by The Peanut Foundation, Mars Inc. and three Chinese academies (the Chinese Academy of Agricultural Sciences, the Henan Academy of Agricultural Sciences, and the Shandong Academy of Agricultural Sciences), but David credits GCP work for paving the way. “GCP research built up the populations and genetic maps that laid the groundwork for the material that then went on to be sequenced.”

Chair of GCP’s Consortium Committee, David Hoisington – formerly ICRISAT’s Director of Research and now Senior Research Scientist and Program Director at the University of Georgia – says the sequencing could be a huge step forward for boosting agriculture in developing countries.

“Researchers and plant breeders now have much better tools available to breed more productive and more resilient groundnut varieties, with improved yields and better nutrition,” he says.

These resilient varieties should be available to farmers across Africa within a few years.

Genetics alone will not lift productivity – farmers’ local knowledge is vital

Improvements in the yield, quality and share of the global market of groundnuts produced by developing countries are already being seen as a result of GCP support, says Vincent Vadez. “But for this trend to continue, the crop’s ability to tolerate drought and resist diseases must be improved without increasing the use of costly chemicals that most resource-poor farmers simply cannot afford,” he says.

While genetic improvements are fundamental to developing the disease resistance and drought tolerance so desperately needed by African farmers, there are other important factors that can influence the overall outcome of a breeding programme, he explains. Understanding the plant itself, the soil and the climate of a region are all vital in creating the kinds of varieties farmers need and can grow in their fields.

Photo: Y Wachira/Bioversity International

Kenyan groundnut farmer Patrick Odima with some of his crop.

“I have grown increasingly convinced that overlooking these aspects in our genetic improvements would be to our peril,” Vincent warns. “There are big gains to be made from looking at very simple sorts of agronomic management changes, like sowing density – the number of seeds you plant per square metre. Groundnuts are often cultivated at seeding rates that are unlikely to achieve the best possible yields, especially when they’re grown in infertile soils.”

For Omari Mponda, now Director of Tanzania’s Agricultural Research Institute at Naliendele (ARI–Naliendele), previously Zonal Research Coordinator and plant breeder, and country groundnut research leader for GCP’s Tropical Legumes I project (TLI; see box below), combining good genetics with sound agronomic management is a matter of success or failure for any crop-breeding programme, especially in poverty-stricken countries.

“Molecular markers by themselves will not address the productivity on the ground,” he says, agreeing with Vincent. “A new variety of groundnut may have very good resistance, but its pods may be too hard, making shelling very difficult. This does not help the poor people, because they can’t open the shells with their bare hands.”

And helping the poor of Africa is the real issue, Omari says. “We must remind ourselves of that.”

This means listening to the farmers: “It means finding out what they think and experience, and using that local knowledge. Only then should the genetics come in. We need to focus on the connections between local knowledge and scientific knowledge. This is vital.”

The Tropical Legumes I project (TLI) was initiated by GCP in 2007 and subsequently incorporated into the Programme’s Legumes Research Initiative (RI). The goal of the RI was to improve the productivity of four legumes – beans, chickpeas, cowpeas and groundnuts – that are important in food security and poverty reduction in developing countries, by providing solutions to overcome drought, poor soils, pests and diseases. TLI was led by GCP and focussed on Africa. Work on groundnut within TLI was coordinated by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT). The partners in the four target countries were Malawi’s Chitedze Research Station, Senegal’s Institut Sénégalais de Recherches Agricoles (ISRA), and Tanzania’sAgricultural Research Institute (ARI). Other partners were France’s Centre de coopération internationale en recherche agronomique pour le développement (CIRAD), the Brazilian Corporation of Agricultural Research (EMBRAPA) and Universidade de Brasil in Brazil, and University of Georgia in the USA. Tropical Legumes II (TLII) was a sister project to TLI, led by ICRISAT on behalf of the International Institute of Tropical Agriculture (IITA) and International Center for Tropical Agriculture (CIAT). It focussed on large-scale breeding, seed multiplication and distribution primarily in sub-Saharan Africa and South Asia, thus applying the ‘upstream’ research results from TLI and translating them into breeding materials for the ultimate benefit of resource-poor farmers. Many partners in TLI also worked on projects in TLII.

Photo: A Diama/ ICRISAT

Participants at a farmer field day in Mali interact with ICRISAT staff and examine different groundnut varieties and books on aflatoxin control and management options.

Local knowledge and high-end genetics working together in Tanzania

Like Malawi, Tanzania has also experienced the full spectrum of constraints to groundnut production – from drought, aflatoxin contamination, poor soil and limited access to new seed, to a lack of government extension officers visiting farmers to ensure they have the knowledge and skills needed to improve their farming practices and productivity.

Although more than one million hectares of Tanzania is groundnut cropping land, the resources supplied by the government have until now been minimal, says Omari, compared to those received for traditional cash crops such as cashews and coffee.

Photo: C Schubert/CCAFS

A farmer and her children near Dodoma, Tanzania, an area where climate change is causing increasing heat and drought. Groundnut is an important crop for local famers, forming the basis of their livelihood together with maize and livestock.

“But the groundnut is now viewed differently by the government in my country as a result of GCP’s catalytic efforts,” Omari says. “More resources are being put into groundnut research.”

In the realm of infrastructure, for instance, the use of GCP funds to build a new irrigation system at Naliendele has since prompted Tanzania’s government to invest further in irrigation for breeder seed production.

“They saw it was impossible for us to irrigate our crops with only one borehole, for instance, so they injected new funds into our irrigation system. We now have two boreholes and a whole new system, which has helped expand the seed production flow. Without GCP, this probably wouldn’t have happened.”

Irrigation, for Omari, ultimately means being able to get varieties to the farmers much faster: “maybe three times as fast,” he says. “This means we’ll be able to speed up the multiplication of seeds – in the past we were relying on rainfed seed, which took longer to bulk and get to farmers.”

With such practical outcomes from GCP’s research and funding efforts and the new genetic resources becoming available, breeders like Omari see a bright future for groundnut research in Tanzania.

Photo: C Schubert/CCAFS

Groundnut farmer near Dodoma, Tanzania.

The gains being made at Naliendele are not only sustainable, Omari explains, but have given the researchers independence and autonomy. “Before we were only learning – now we have become experts in what we do.”

Prior to GCP, Omari and his colleagues were used to conventional breeding and lacked access to cutting-edge science.

“We used to depend on germplasm supplied to us by ICRISAT, but now we see the value in learning to use molecular markers in groundnut breeding to grow our own crosses, and we are rapidly advancing to a functional breeding programme in Tanzania.”

Omari says he and his team now look forward to the next phase of their research, when they expect to make impact by practically applying their knowledge to groundnut production in Tanzania.

Similar breeding success in Senegal

Photo: C Schubert/CCAFS

Harvesting groundnuts in Senegal.

Issa Faye became involved in GCP in 2008 when the programme partly funded his PhD in fresh seed dormancy in groundnuts. “I was an example of a young scientist who was trained and helped by GCP in groundnut research,” he says.

“I remember when I was just starting my thesis, my supervisor would say, ‘You are very lucky because you will not be limited to using conventional breeding. You are starting at a time when GCP funding is allowing us to use marker-assisted selection [MAS] in our breeding programme’.”

The importance of MAS in groundnut breeding, Issa says, cannot be overstated.

“It is very difficult to distinguish varieties of cultivated groundnut because most of them are morphologically very similar. But if you use molecular markers you can easily distinguish them and know the diversity of the matter you are using, which makes your programme more efficient. It makes it easier to develop varieties, compared to the conventional breeding programme we were using before we started working with GCP.”

By using markers that are known to be linked to useful genes for traits such as drought tolerance, disease resistance, or resistance to aflatoxin-producing fungi, breeders can test plant materials to see whether or not they are present. This helps them to select the best parent plants to use in their crosses, and accurately identify which of the progeny have inherited the gene or genes in question without having to grow them all to maturity, saving time and money.

Photo: S Sridharan/ICRISAT

These women in Salima District, Malawi, boil groundnuts at home and carry their tubs to the Siyasiya roadside market.

Senegal, like other developing countries, does not have enough of its own resources for funding research activities, explains Issa. “We can say we are quite lucky here because we have a well-developed and well-equipped lab, which is a good platform for doing molecular MAS. But we need to keep improving it if we want to be on the top. We need more human resources and more equipment for boosting all the breeding programmes in Senegal and across other regions of West Africa.”

Recently, Issa says, the Senegalese government has demonstrated awareness of the importance of supporting these activities. “We think that we will be receiving more funds from the government because they have seen that it’s a kind of investment. If you want to develop agriculture, you need to support research. Funding from the government will be more important in the coming years,” he says.

“Now that we have resources developed through GCP, we hope that some drought-tolerant varieties will come and will be very useful for farmers in Senegal and even for other countries in West Africa that are facing drought.”

It’s all about poverty

“The achievements of GCP in groundnut research are just the beginning,” says Vincent. The legacy of the new breeding material GCP has provided, he says, is that it is destined to form the basis of new and ongoing research programmes, putting research well ahead of where it would otherwise have been.

“There wasn’t time within the scope of GCP to develop finished varieties because that takes such a long time, but these products will come,” he says.

For Vincent, diverse partnerships facilitated by GCP have been essential for this to happen. “The groundnut work led by ICRISAT and collaborators in the target countries – Malawi, Senegal, and Tanzania – has been continuously moving forward.”

Photo: S Sridharan/ICRISAT

Groundnut harvesting at Chitedze Agriculture Research Station, Malawi.

Issa agrees: “It was fantastic to be involved in this programme. We know each other now and this will ease our collaborations. We hope to keep working with all the community, and that will obviously have a positive impact on our work.”

For Omari, a lack of such community and collaboration can only mean failure when it comes to addressing poverty.

“If we all worked in isolation, a lot of money would be spent developing new varieties but nothing would change on the ground,” he says. “Our work in Tanzania is all about the problem of poverty, and as scientists we want to make sure the new varieties are highly productive for the farmers around our area. This means we need to work closely with members of the agricultural industry, as a team.”

Omari says he and his colleagues see themselves as facilitators between the farmers of Tanzania and the ‘upstream end’ of science represented by ICRISAT and GCP. “We are responsible for bringing these two ends together and making the collaboration work,” he says.

Only from there can we come up with improved technologies that will really succeed at helping to reduce poverty in Africa.”

As climate change threatens to aggravate poverty more and more in the future, the highly nutritious, drought-tolerant groundnut may well be essential to sustain a rapidly expanding global population.

By developing new, robust varieties with improved adaptation to drought, GCP researchers are well on the way to increasing the productivity and profitability of the groundnut in some of the poorest regions of Africa, shifting the identity of the humble nut to potential crop champion for future generations.

More links

Photo: S Sridharan/ICRISAT

Oswin Madzonga, Scientific Officer at ICRISAT-Lilongwe, visits on-farm trials near Chitala Research Station in Salima, Malawi, where promising disesase-resistant varieties are being tested real life conditions.

Jun 192015
 
Photo: N Palmer/CIAT

Bean Market in Kampala, Uganda.

Common beans are the world’s most important food legume, particularly for subsistence and smallholder farmers in East and Southern Africa. They are a crucial source of protein, are easy to grow, are very adaptable to different cropping systems, and mature quickly.

To some, beans are ‘a near-perfect food’ because of their high protein and fibre content plus their complex carbohydrates and other nutrients. One cup of beans provides at least half the recommended daily allowance of folate, or folic acid – a B vitamin that is especially important for pregnant women to prevent birth defects. One cup also supplies 25–30 percent of the daily requirement of iron, 25 percent of that of magnesium and copper, and 15 percent of the potassium and zinc requirement.

Unfortunately, yields in Africa are well below their potential – between 20 and 30 percent below. The main culprit is drought, which affects 70 percent of Africa’s major bean-producing regions. Drought is especially severe in the mid-altitudes of Ethiopia, Kenya, Malawi and Zimbabwe, as well as across Southern Africa.

“For the past seven or eight years, rains have been very unreliable in central and northern Malawi,” says Virginia Chisale, a bean breeder with Malawi’s Department of Agricultural Research and Technical Services.

“In the past, rains used to be very reliable and people were able to know the right time to plant to meet the rains in critical conditions,” she says. “Now these primary agriculture regions are either not receiving rain for long periods of time, or rains are not falling at the right time.”

Virginia recounts that during the 2011/12 cropping season there were no rains soon after planting, when it is important that beans receive moisture. Such instances can cut bean yields by half.

Photo: N Palmer/CIAT

Steve Beebe in the field.

“Drought is a recurrent problem of rainfed agriculture throughout the world,” says Steve Beebe, a leading bean breeder with the International Center for Tropical Agriculture (CIAT). “Since over 80 percent of the world’s cultivated lands are rainfed, drought stress has major implications for global economy and trade.”

Steve was the Product Delivery Coordinator for the beans component of the Legumes Research Initiative (RI), part of Phase II of the CGIAR Generation Challenge Programme (GCP). The RI incorporated several projects, the biggest of which was Tropical Legumes I (TLI) (see box). The main objective of the work on beans within TLI was to identify and develop drought-tolerant varieties using marker-assisted breeding techniques. The resulting new varieties were then evaluated for their performance in Ethiopia, Kenya, Malawi and Zimbabwe.

“It’s vital that we develop high-yielding drought-tolerant varieties so as to help farmers, particularly in developing countries, adapt to drought and produce sustained yields for their families and local economies,” says Steve.

The Tropical Legumes I project (TLI) was initiated by GCP in 2007 and subsequently incorporated into the Programme’s Legumes Research Initiative (RI). The goal of the RI was to improve the productivity of four legumes – beans, chickpeas, cowpeas and groundnuts – that are important in food security and poverty reduction in developing countries, by providing solutions to overcome drought, poor soils, pests and diseases. TLI was led by GCP and focussed on Africa. Work on beans within TLI was coordinated by the International Center for Tropical Agriculture (CIAT). The partners in the four target countries were Ethiopia’s South Agricultural Research Institute (SARI), the Kenya Agricultural Research Institute (now known as the Kenya Agricultural and Livestock Research Organization, KALRO), Malawi’s Department of Agricultural Research and Technical Services (DARTS) and Zimbabwe’s Crop Breeding Institute (CBI) of the Department of Research and Specialist Services (DR&SS). Cornell University in the USA was also a partner. Tropical Legumes II (TLII) was a sister project to TLI, led by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) on behalf of the International Institute of Tropical Agriculture (IITA) and CIAT. It focussed on large-scale breeding, seed multiplication and distribution primarily in sub-Saharan Africa and South Asia, thus applying the ‘upstream’ research results from TLI and translating them into breeding materials for the ultimate benefit of resource-poor farmers. Many partners in TLI also worked on projects in TLII.

For an overview of the work on beans from the perspectives of four different partners, watch our video below, “The ABCs of bean breeding”.

What makes a plant drought tolerant?

The question of what makes a plant drought tolerant is one that breeders have debated for centuries. No single plant characteristic or trait can be fully responsible for protecting the plant from the stress of intense heat and reduced access to water.

“It’s a difficult question to answer for any plant, including beans,” says Steve. “Once you do isolate a trait genetically, it can often be difficult to identify this trait in a plant in the field, for example, identifying the architecture and length of a plant’s roots.”

Phenotyping is an important process in conventional plant breeding. It involves identifying and measuring the presence of physical traits such as seed colour, pod size, stem thickness or root length. Gathering data about a range of such characteristics across a number of different plant lines helps breeders decide which plants to use as parents in crosses and which of the progeny have inherited useful traits.

Root length has long been thought of as a drought-tolerance trait: the longer the root, the more chance it has of tapping into moisture stored deeper in the soil profile.

Given, however, that it is difficult to inspect root length in the field, researchers at CIAT have been exploring other more accessible drought-tolerance traits they can more easily identify and measure. One of these is measuring the weight of the plants’ seeds.

Photo: N Palmer/CIAT

Comparison between varieties in trials of drought tolerant beans at CIAT’s headquarters in Colombia.

Fat beans indicate plants coping with drought stress

“We measure seed weight because we are discovering that under drought stress, drought-tolerant bean varieties will divert sugars from their leaves, stems and pods to their seed,” says Steve. “We call this trait ‘pod filling’, and for us it is the most important drought-tolerance trait to be found over the last several years.”

Finding bean plants with larger, heavier seeds when growing under drought conditions indicates that the plants are coping well, and means farmers’ yields are maintained.

As part of GCP’s Legumes RI, African partners like Virginia have been measuring the seed weight of several advanced breeding lines, which can be used as parents to develop new varieties. These breeding lines have been bred by CIAT and demonstrate this pod-filling process and consequent tolerance of drought.

Although this measurement is relatively cheap and easy for breeders all over the world to do, Steve and his team are interested in finding an even more efficient way to spot plants that maintain full pods under drought.

“We are trying to understand which genes control this trait so we can use molecular-assisted breeding techniques to determine when the trait is present,” says Steve. Having identified several regions of genes related to pod filling, he and his team have developed molecular markers to help breeders identify which plants have these desired genes. “The use of molecular markers in selection significantly reduces the time and cost of the breeding process, making it more efficient. This means that we get improved varieties out to farmers more quickly.”

Photo: N Palmer/CIAT

Bean farmer in Rwanda.

Molecular markers (also known as DNA markers) are used by researchers as ‘flags’ to identify particular genes within a plant’s genome (DNA) that control desired traits, such as drought tolerance. These markers are themselves fragments of DNA that highlight particular genes or regions of genes by binding near them.

To use an analogy, think of a story as the plant’s genome: its words are the plant’s genes, and a molecular marker works like a text highlighter. Molecular markers are not precise enough to highlight specific words (genes), but they can highlight sentences (genomic regions) that contain these words (genes), making it easier and quicker to identify whether or not they are present.

Photo: J D'Amour/HarvestPlus

Beans from Rwanda.

Plant breeders can use molecular markers from early on in the breeding process to choose parents for their crosses and determine whether progeny they have produced have the desired trait, based on testing only a small amount of seed or seedling tissue.

“If the genes are present, we grow the progeny and conduct the appropriate phenotyping; if not, we throw the progeny away,” explains Steve. “This saves us resources and time because we need to grow and phenotype only the few hundred progeny which we know have the desired genes, instead of a few thousand progeny, most of which would not possess the gene.”

Outsourcing genotyping to the UK Steve says a significant contribution made by GCP was facilitating a deal with a private UK company (LGC Genomics, formerly KBioscience) that is able to quickly and cheaply genotype leaf samples sent to them by African breeders. The company then forwards the data to the International Center for Tropical Agriculture (CIAT), who analyse it and let the breeders in Africa know which progeny contain the desired genes and are suitable for breeding, and which ones to throw away.  “The whole process takes roughly four weeks, but saves the breeders the time and effort to grow all progeny,” says Steve. “This system works well for countries that don’t have the capacity or know-how to do the molecular work,” says Darshna Vyas, a plant genetics specialist with LGC Genomics. “Genotyping has advanced to a point where even larger labs around the world choose to outsource their genotyping work, as it is cheaper and quicker than if they were to equip their lab and do it themselves. We do hundreds of thousands of genotyping samples a day – day in, day out. It’s our business.”

GCP has supported this foundation work, building on the extensive bean research already done by CIAT dating back to the 1970s, to develop molecular markers not only for drought-tolerance traits such as pod filling, but also for traits associated with resistance to important insect and disease menaces.

“Under drought conditions, plants become more susceptible to pests and diseases, so it was important that we also try to identify and include resistance traits in the drought-tolerant progeny,” says Steve.

Drought is but one plant stressor – diseases and pests wreak havoc too

Photo: W Arinaitwe/CIAT/PABRA

Common bacterial blight on bean.

The bean diseases that farmers in Ethiopia, Kenya, Malawi and Zimbabwe continually confront are angular leaf spot, bean common mosaic virus, common bacterial blight and rust. Key insect pests are bean stem maggot and aphids.

“We’ve had reports of bean stem maggot and bean common mosaic virus wiping out a whole field of beans,” says Virginia. “Although angular leaf spot and common bacterial blight are not as damaging, they can still reduce yields by over 50 percent.”

Virginia says this is devastating for farmers in Malawi, many of whom only have enough land and money to grow beans to feed their families and sell what little excess there is at market to purchase other necessities.

“This is why we are excited by the prospect of developing not just drought-tolerant varieties, but drought-tolerant varieties with disease and pest resistance as well,” says Virginia.

Virginia’s team in Malawi – along with other breeders in Ethiopia, Kenya and Zimbabwe – are currently using over 200 Mesoamerican and Andean bean breeding lines supplied by CIAT to help breed for drought tolerance and disease and pest resistance. Although many do not yet have the capacity to do molecular breeding in their countries, thanks to advances in plant science it is becoming more feasible and cheaper to outsource molecular breeding stages of the process (see box above).

“With help from GCP and CIAT, we have successfully crossed a line from CIAT with some local varieties to produce plants that are high yielding and resistant to most common bean diseases,” Virginia says.

Photo: ILRI

Malawian farmer Jinny Lemson grows beans to feed her livestock.

Ethiopia’s new bean breeders

Photo: ILRI

Young women sorting beans after a harvest in Ethiopia.

One man who has been helping build this new breeding capacity is Bodo Raatz, a molecular geneticist who joined CIAT and GCP’s Legumes RI in late 2011.

“We’ve [CIAT] hosted several African PhD students here in Colombia and have conducted several workshops in Colombia and Africa too,” says Bodo.

“At the workshops we teach local breeders and technicians how to use genetic tools and markers for advanced breeding methods, phenotyping and data management. The more people there are who can do this work, the quicker new varieties will filter through to farmers.”

Bodo says he has found delivering the training both personally and professionally rewarding, especially “seeing the participants understand the concepts and start using the tools and techniques to develop new lines [of bean varieties] and contribute to the project.”

One national breeder whom Bodo has seen advance from the training is Daniel Ambachew, then a bean breeder at the Southern Agricultural Research Institute (SARI) in Ethiopia.

Daniel started as a GCP-funded Master’s student enrolled at Haramaya University, Ethiopia, evaluating bean varieties with both tolerance to drought and resistance to bean stem maggot. He eventually became the Ethiopian project leader for beans within GCP’s Legumes RI.

“Daniel is currently one of only a handful of bean breeders in Ethiopia who are using molecular-assisted breeding techniques to breed new varieties,” says Bodo. “It’s quite an achievement, especially now that he has taken on the lead role in Ethiopia.”

Photo: N Palmer/CIAT

Buying and selling at a bean market in Kampala, Uganda.

For Daniel, learning about and using the new molecular-breeding techniques has been an exciting new challenge. “The most interesting part of the technology is that it helps us understand what is going on in the plant at a molecular level and lets us know if the crosses we are making are successful and the genes we want are present,” says Daniel. “All this helps improve our efficiency and speeds up the time it takes us to breed and release new varieties for farmers.”

By the end of 2014, Daniel and his team had finished the third year of trials and had several drought-tolerant lines ready for national trials in 2015 and eventual release in 2016.

Between 2012 and 2014, Daniel, and two other breeders from SARI, attended GCP’s three-year Integrated Breeding Multiyear Course, learning how to design molecular-assisted breeding trials; collect, analyse and interpret genotypic and phenotypic data from the trials; and manage data using the GCP’s Integrated Breeding Platform (IBP), particularly its Breeding Management System (BMS).

“The IBP is a really fantastic tool,” says Daniel. “During the course we learnt about the importance of recording clear and consistent phenotypic data, and the IBP helps us to do this as well as store it in a database. It makes it easier to refer to and learn from the past. I’m now trying to pass on the knowledge I’ve learnt as well as create and implement a data-management policy for all plant breeders and technicians in our institute.”

Bodo agrees with Daniel about the importance of IBP and believes it will be a true legacy of GCP beyond the Programme’s end in 2014. “The Platform has been designed to be the main data-management platform for plant breeders. It allows breeders to talk the same language and will reduce the need for learning new systems.”

Daniel says the challenge for his institute now is to build further capacity among staff – and to retain it. “At the moment we only have two bean breeders,” says Daniel. “It’s hard to retain research staff in Ethiopia as salaries are very low, so people move on to new, higher paying positions when they get the chance. It’s not unique to Ethiopia, but true of all Africa.”

Photo: O Thiong'o/CIAT/PABRA

Bean trials at KALRO in Kenya.

Kenya chasing higher bean yields

Across the border, Kenya has also been facing staffing issues.

“We are behind Ethiopia, Malawi and Zimbabwe in terms of our capacity and our trials,” says David Karanja, a bean breeder and project leader at the Kenya Agricultural and Livestock Research Organisation (KALRO, formerly the Kenya Agricultural Research Institute, or KARI). “At the start of the project, we didn’t have a breeder to lead the project for almost two years. However, we are now rapidly catching up with the others.”

And it’s a good thing too, as the country is in need of higher yielding beans to accommodate its population’s insatiable appetite for the crop. Out of the four target African countries, Kenya is the largest bean producer and consumer. As such, the country relies on beans imports from Ethiopia, Malawi, Tanzania and Uganda.

“A lot of families eat beans every day,” says David. “On average, the population eats 14–16 kilograms per person each year, but in western Kenya the average is over 60 kilograms.”

Photo: CIMMYT

Githeri, a Kenyan staple food made with maize and beans.

Kenyans consume an average total of 400,000 tonnes of beans each year, consistently more than the country produces. Projected trends in population growth indicate that this demand for beans will continue to increase by three to four percent annually.

Even though the area planted to beans has been increasing, David says farmers and breeders need to work together to improve productivity, which is well below where it should be. “The national average yield is 100 kilograms per hectare, which can range from 50 kilograms up to 700 kilograms, depending on whether we experience a drought, or a pest or disease epidemic,” explains David. “The minimum target we should be aiming for is 1,200 kilograms per hectare.”

Such a figure may seem impossible, but David believes that new breeding techniques and the varieties KALRO are producing with the help of CIAT are providing hope that farmers can reach these lofty goals.

“We have several bean lines that are showing good potential to produce higher yields under drought conditions and also have resistance to diseases like rust and mosaic virus,” says David. “They are currently under national trials, and we are confident these will be released to farmers in 2015.”

Photo: O Thiong'o/CIAT/PABRA

Varieties fare differently in KALRO bean trials in Kenya.

Commercialising beans

Photo: CIAT

Maturing bean pods.

“Many subsistence farmers have limited access to good quality bean seeds; they lack knowledge of good crop, pest and disease management; and they have poor post-harvest storage facilities,” says Godwill Makunde, who was previously a breeder at Zimbabwe’s Crop Breeding Institute (CBI) and leader of GCP’s Legumes RI bean project in Zimbabwe.

TLI’s sister project, Tropical Legumes II (TLII, see box above), led by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), provided the route by which the upstream work of TLI would have impact in helping these farmers, seeking to deliver the new varieties developed under TLI into their hands. As part of TLII, Godwill, his successor Bruce Mutari, and other African partners worked on developing sustainable seed systems.

“Because beans are self-pollinating, which means each crop is capable of producing seed exactly as it was sown, farmers tend to propagate seed on farm,” says Godwill. “While this can be cost effective, it can reduce farmers’ access to higher yielding, tolerant lines, like the ones we are currently producing.”

In none of the partner countries of TLI and TLII are there formal systems for producing and disseminating bean seeds. Godwill and other partners are working with seed companies on developing a sustainable model where both farmers and seed companies can benefit.

Success built on a solid foundation

Photo: N Palmer/CIAT

Field workers tend beans in Rwanda.

A key to the success of the beans component of GCP’s Legumes RI, according to Ndeye Ndack Diop, GCP’s Capacity Building Theme Leader and TLI Project Manager, has been partners’ existing relationships with each other.

“Many of the partners are part of a very strong network of bean breeders: the Bean Coordinated Agricultural Project [BeanCAP],” explains Ndeye Ndack, adding that the TLI and BeanCAP networks benefited each other.

BeanCAP released more than 1,500 molecular markers to TLI researchers, which have helped broaden the genetic tools available to developing-country bean breeders.

TLI was also able to leverage and advance previous BeanCAP work and networks. For example, it was through this collaboration that GCP was introduced to LGC Genomics, a company it then worked with on many other crop projects.

To sustain integrated breeding practices beyond the Programme’s close in 2014, GCP established Communities of Practice (CoPs) that are discipline- and commodity-oriented.

“GCP’s CoP for beans has also helped to broaden both the TLI and BeanCAP networks too,” says Ndeye Ndack. “The ultimate goal of the CoPs is to provide a platform for community problem solving, idea generation and information sharing.”

Developing physical capacity

Besides developing human capacity, GCP has also invested in developing infrastructure in Ethiopia, Kenya and Zimbabwe.

SARI now has an irrigation system to enable them to conduct drought trials year round. “We have 12.5 hectares of irrigation now, which we use to increase our efficiency and secure our research,” says Daniel. “We can also increase seed with this irrigation during the off-season and develop early generation seeds for seed producers.”

In Zimbabwe, CBI received specialised equipment that enables them to extract DNA and send it for genotyping in the UK.

Both SARI and CBI also received automatic weather stations from GCP for high-precision climatic data capture, with automated data loading and sharing with other partners in the network.

Delivering the right beans to farmers

Back in Malawi, Virginia says another important facet of the TLII project is that researchers understand what qualities farmers want in their beans. “It’s no use developing higher yielding beans if the farmer doesn’t like the colour, or they don’t taste nice,” she says. “For example, consumers in central Malawi prefer khaki or ‘sugar beans’, which are tan with brown, black or red speckles. While those in southern Malawi tend to prefer red beans. Farmers know this and will grow beans that they know consumers will want.”

Photo: N Palmer/CIAT

Diversity at bean market in Masaka, Uganda.

Breeders in all four countries have been conducting workshops and small trials with farmers to find out this information. In Kenya, David finds farmer participation a great way to promote the work they are doing and show the impact the new drought-tolerant and disease-resistant lines can have.

“Farmers are excited and want to grow these varieties immediately when they see for themselves the difference in yield these new varieties can produce compared to their regular varieties,” says David. “They understand the pressure on them to produce more yields and are grateful that these varieties are becoming more readily available as well as tailored to their needs.”

For Steve, such anecdotes provide him and his collaborators with incentives to continue their quest to discover more molecular markers associated with drought tolerance, post-GCP.

“It’s a testament to everyone involved that we have been able to develop these advanced lines with pod-filling traits using molecular techniques, and make them available to farmers in six years instead of ten,” says Steve.

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Crop science and collaboration help African farmers feed India’s appetite for chickpeas

Photo: ICRISAT

Indian chickpea farmer with her harvest.

India loves chickpeas. With its largely vegetarian population, it has long been the world’s biggest producer and consumer of the nutritious legume. In recent years, however, India’s appetite for chickpea has outstripped production, and the country is also now the world’s biggest importer. With a ready market and new drought-tolerant varieties of chickpea, millions of smallholder African farmers are ready to make up India’s shortfall, improving livelihoods along the way and ensuring food security for some of the world’s most resource-poor countries.

GCP achieved real impacts in chickpea by catalysing and facilitating the deployment of advanced crop science, particularly molecular breeding, in the development of drought-tolerant varieties for both Africa and Asia. Over the course of its research, it also contributed to major advances in chickpea science and genomic knowledge.

Although India boasts the world’s biggest total chickpea harvest, productivity has been low in recent years with yields of less than one tonne per hectare, largely due to drought in the south of the country where much chickpea is grown. The country is relying increasingly on exports from producers in sub-Saharan Africa to supplement its domestic supply.

Drought has been hindering chickpea yields in Africa too, however, and this is a major concern not only for Africa but also for India. Ethiopia and Kenya are Africa’s largest chickpea producers, and both countries have been producing chickpea for export. However, their productivity has been limited, mainly because of heat stress and moisture loss, as well as by a lack of access to basic infrastructure and resources.

Indeed, drought has been the main constraint to chickpea productivity worldwide, and in countries such as Ethiopia and Kenya this is often made worse by crop disease, poor soil quality and limited farmer resources. While total global production of chickpea is around 8.6 million tonnes per year, drought causes losses of around 3.7 million tonnes worldwide.

A decade ago, chickpea researchers, supported by the CGIAR Generation Challenge Programme (GCP), started to consider the potential for developing new drought-tolerant varieties that could help boost the world’s production.

They posed this question: If struggling African farmers were armed with adequate resources, could they make up India’s shortfall by growing improved chickpea varieties for export? Empowering farmers to stimulate and sustain their own food production, it was proposed, would not only offer food security to millions of farmers, but could ultimately secure future chickpea exports to India.

Photo: S Sridharan/ ICRISAT

An Ethiopian farmer harvests her chickpea crop.

In 2007, GCP kicked off a plan for a multiphased, multithemed Tropical Legumes I (TLI) project, which later became part of, and the largest project within, the GCP Legumes Research Initiative (RI; see box below) – the chickpea component of which would involve collaboration between researchers from India, Ethiopia and Kenya. The scope was not only to develop improved, drought-tolerant chickpeas that would thrive in semiarid conditions, but also to ensure that these varieties would be growing in farmers’ fields across Africa and South Asia within a decade.

“We knew our task would not be complete until we had improved varieties in the hands of farmers,” says GCP researcher Paul Kimurto from the Faculty of Agriculture, Egerton University, Kenya.

The success of GCP research in achieving these goals has opened up great opportunities for East African countries such as Ethiopia and Kenya, which are primed and ready to take advantage of a guaranteed chickpea market.

The Tropical Legumes I project (TLI) was initiated by GCP in 2007 and subsequently incorporated into the Programme’s Legumes Research Initiative (RI). The goal of the RI was to improve the productivity of four legumes – beans, chickpeas, cowpeas and groundnuts – that are important in food security and poverty reduction in developing countries, by providing solutions to overcome drought, poor soils, pests and diseases. TLI was led by GCP and focussed on Africa. Work on chickpea within TLI was coordinated by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT). Target-country partners were the Ethiopian Institute of Agricultural Research (EIAR), Egerton University in Kenya and the Indian Institute of Pulses Research. The National Center for Genome Resources in the USA was also a partner. Tropical Legumes II (TLII) was a sister project to TLI, led by ICRISAT on behalf of the International Institute of Tropical Agriculture (IITA) and the International Center for Tropical Agriculture (CIAT). It focussed on large-scale breeding, seed multiplication and distribution primarily in sub-Saharan Africa and South Asia, thus applying the ‘upstream’ research results from TLI and filtering them downstream into breeding materials for the ultimate benefit of resource-poor farmers. Many partners in TLI also worked on projects in TLII.

How drought affects chickpea

Chickpea is a pretty tough customer overall, being able to withstand and thrive on the most rugged and dry terrains, surviving with no irrigation – only the moisture left deep in the soil at the end of the rainy season.

Yet the legume does have one chink in its armour: if no rain falls at its critical maturing or ripening stage (otherwise known as the grain-filling period), crop yields will be seriously affected. The size and weight of chickpea legumes is determined by how successful this maturing stage is. Any stress, such as drought or disease, that occurs at this time will reduce the crop’s yield dramatically.

In India, this has been a particular problem for the past 40 years or so, as chickpea cropping areas have shifted from the cooler north to the warmer south.

“In the 1960s and 1970s when the agricultural Green Revolution introduced grain crops to northern India, chickpeas began to be replaced there by wheat or rice, and grown more in the south,” says Pooran Gaur from the International Crop Research Institute for the Semi-Arid Tropics (ICRISAT), headquartered in India. Pooran was an Activity Leader for the first phase of TLI and Product Delivery Coordinator for the chickpea component of the Legumes RI.

This shift meant the crop was no longer being grown in cooler, long-season environments, but in warmer, short-season environments where drought and diseases like Fusarium wilt have inhibited productivity.

“We have lost about four or five million hectares of chickpea growing area in northern India in the decades since that time,” says Pooran. “In the central and southern states, however, chickpea area more than doubled to nearly five million hectares.”

Escaping drought in India

“The solution we came up with was to develop varieties that were not only high yielding, but could also mature earlier and therefore have more chance of escaping terminal drought,” Pooran explains.

“Such varieties could also allow cereal farmers to produce a fast-growing crop in between the harvest and planting of their main higher yielding crops,” he says.

New short-duration varieties are expected to play a key role in expanding chickpea area into new niches where the available crop-growing seasons are shorter.

“In southern India now we are already seeing these varieties growing well, and their yield is very high,” says Pooran. “In fact, productivity has increased in the south by about seven to eight times in the last 10–12 years.”

The southern state of Andhra Pradesh, once considered unfavourable for chickpea cultivation, today has the highest chickpea yields (averaging 1.4 tonnes/hectare) in India, producing almost as much chickpea as Australia, Canada, Mexico and Myanmar combined.

Photo: ICRISAT

Indian chickpea farmer with her harvest.

Developing new varieties: Tropical Legumes I in action

GCP-supported drought-tolerance breeding activities in chickpea created hugely valuable breeding materials and tools during the Programme’s decade of existence, focussing not only in India but African partner countries of Ethiopia and Kenya too. A key first step in Phase I of TLI was to create and phenotype – i.e. measure and record the observable characteristics of – a chickpea reference set. This provided the raw information on physical traits needed to make connections between phenotype and genotype, and allowed breeders to identify materials likely to contain drought tolerance genes. This enabled the creation in Phase II of breeding populations with superior genotypes, and so the development of new drought-tolerant prebreeding lines to feed into TLII.

A significant number of markers and other genomic resources were identified and made available during this time, including simple sequence repeats (SSRs), single nucleotide polymorphisms (SNPs) and Diversity Array Technologies (DArT) arrays. The combination of genetic maps with phenotypic information led to the identification of an important ‘hot spot’ region containing quantitative trait loci (QTLs) for several drought-related traits.

Two of the most important molecular-breeding approaches, marker-assisted backcrossing (MABC) and marker-assisted recurrent selection (MARS), were then employed extensively in the selection of breeding materials and introgression of these drought-tolerance QTLs and other desired traits into elite chickpea varieties.

Photo: L Vidyasagar/ ICRISAT

Developing chickpea pods

Markers – DNA sequences with known locations on a chromosome – are like flags on the genetic code. Using them in molecular breeding involves several steps. Scientists must first discover a large number of markers, of which only a small number are likely to be polymorphic, i.e. to have different variants. These are then mapped and compared with phenotypic information, in the hope that just one or two might be associated with a useful trait. When this is the case, breeders can test large quantities of breeding materials to find out which have genes for, say, drought tolerance without having to grow plants to maturity.

The implementation of techniques such as MABC and MARS has become ever more effective over the course of GCP’s work in chickpea, thanks to the emergence and development of increasingly cost-effective types of markers such as SNPs, which can be discovered and explored in large numbers relatively cheaply. The integration of SNPs into chickpea genetic maps significantly accelerated molecular breeding.

The outcome of all these molecular-breeding efforts has been the development and release of locally adapted, drought-tolerant chickpea varieties in each of the target countries – Ethiopia, Kenya and India – where they are already changing lives with their significantly higher yields. Further varieties are in the pipeline and due for imminent release, and it is anticipated that, with partner organisations adopting the use of molecular markers as a routine part of their breeding programmes, many more will be developed over the coming years.

Molecular breeding in TLI was done in conjunction with target-country partners, with at least one cross carried out in each country. ICRISAT also backed up MABC activities with additional crosses. The elite lines that were developed underwent multilocation phenotyping in the three target countries and the best-adapted, most drought-tolerant lines were promoted in TLII.

The project placed heavy emphasis on capacity building for the target-country partners. Efforts were made, for instance, to help researchers and breeders at Egerton University in Kenya and the Ethiopian Institute of Agricultural Research (EIAR) in Ethiopia to undertake molecular breeding activities. At least one PhD and two Master’s students each from Kenya, Ethiopia and India were supported throughout this capacity-building process.

The magic of genetic diversity

One of the important advances in chickpea science supported by GCP, as part of TLI and its mission to develop drought-tolerant chickpea genotypes, was the development of the first ever chickpea multiparent advanced generation intercross (MAGIC) population.

It was created using eight well-adapted and drought-tolerant desi chickpea cultivars and elite lines from different genetic origins and backgrounds, including material from Ethiopia, Kenya, India and Tanzania. These were drawn from the chickpea reference set that GCP had previously developed and phenotyped, allowing an effective strategic selection of parental lines. The population was created by crossing these over several generations in such a way as to maximise the mix of genes in the offspring and ensure varied combinations.

MAGIC populations like these are a valuable genetic resource that makes trait mapping and gene discovery much easier, helping scientists identify useful genes and create varieties with enhanced genetic diversity. They can also be directly used as source material in breeding programmes; already, phenotyping a subset of the chickpea MAGIC population has led to the identification of valuable chickpea breeding lines that had favourable alleles for drought tolerance.

Through links with future molecular-breeding projects, it is expected that the investment in the development of MAGIC populations will benefit both African and South Asian chickpea production. GCP was also involved in developing MAGIC populations for cowpea, rice and sorghum, which were used to combine elite alleles for both simple traits, such as aluminium tolerance in sorghum and submergence tolerance in rice, and complex traits, such as drought or heat tolerance.

Decoding the chickpea genome

Photo: ICRISAT

Chickpea seed

In 2013, GCP scientists, working with other research organisations around the world, announced the successful sequencing of the chickpea genome. This major breakthrough is expected to lead to the development of even more superior varieties that will transform chickpea production in semiarid environments.

A collaboration of 20 international research organisations under the banner of the International Chickpea Genome Sequencing Consortium (ICGSC), led by ICRISAT, identified more than 28,000 genes and several million genetic markers. These are expected to illuminate important genetic traits that may enhance new varieties.

“The value of this new resource for chickpea improvement cannot be overstated,” says Doug Cook from the University of California, Davis (UC Davis), United States. “It will provide the basis for a wide range of studies, from accelerated breeding, to identifying the molecular basis of a range of key agronomic traits, to basic studies of chickpea biology.”

Doug was one of three lead authors on the publication of the chickpea genome, along with Rajeev Varshney of ICRISAT, who was Principal Investigator for the chickpea work in GCP’s Legumes RI, and Jun Wang, Director of the Beijing Genomics Institute (BGI) of China.

“Making the chickpea genome available to the global research community is an important milestone in bringing chickpea improvement into the 21st century, to address the nutritional security of the poor – especially the rural poor in South Asia and Africa,” he says.

Increased food security will mean higher incomes and a better standard of living for farmers across sub-Saharan Africa.

For Pooran Gaur, GCP played the role of catalyst in this revolution in genomic resource development. “GCP got things started; it set the foundation. Now we are in a position to do further molecular breeding in chickpea.”

The chickpea genome-sequencing project was partly funded by GCP. Other collaborators included UC Davis and BGI-Shenzhen, with key involvement of national partners in India, Canada, Spain, Australia, Germany and the Czech Republic.

In September 2014, ICRISAT received a grant from the Indian Government for a three-year project to further develop chickpea genomic resources, by utilising the genome-sequence information to improve chickpea.

 Photo: L Vidyasagar/ICRISAT

Indian women roast fresh green chickpeas for an evening snack in Andhra Pradesh, India.

Chickpea success in Africa: new varieties already changing lives

With high-yielding, drought tolerant chickpea varieties emerging from the research efforts in molecular breeding, GCP’s partners also needed to reach out to farmers. Teaching African farmers about the advantages of growing chickpeas, either as a main crop or a rotation crop between cereals, has brought about a great uptake in chickpea production in recent years.

A key focus during the second phase of TLI, and onward into TLII, was on enhancing the knowledge, skills and resources of local breeders who have direct links to farmers, especially in Ethiopia and Kenya, and so also build the capacity of farmers themselves.

“We’ve held open days where farmers can interact with and learn from breeders,” says Asnake Fikre, Crop Research Director for EIAR and former TLI country coordinator of the chickpea work in Ethiopia.

“Farmers are now enrolled in farmer training schools at agricultural training centres, and there are also farmer participatory trials.

“This has given them the opportunity to participate in varietal selection with breeders, share their own knowledge and have their say in which varieties they prefer and know will give better harvest, in the conditions they know best.”

EIAR has also been helping train farmers to improve their farm practices to boost production and to become seed producers of these high-yielding chickpea varieties.

“Our goal was to have varieties that would go to farmers’ fields and make a clearly discernible difference,” says Asnake. “Now we are starting to make that kind of impact in my country.”

In fields across Ethiopia, the introduction of new, drought-tolerant varieties has already brought a dramatic increase in productivity, with yields doubling in recent years. This has transformed Ethiopia’s chickpea from simple subsistence crop to one of great commercial significance.

“Targeted farmers are now planting up to half their land with chickpea,” Asnake says. “This has not only improved the fertility of their soil but has had direct benefits for their income and diets.”

Varieties like the large-seeded and high-valued kabuli have presented new opportunities for farmers to earn extra income through the export industry, and indeed chickpea exports from eastern Africa have substantially increased since 2001.

Photo: A Paul-Bossuet/ICRISAT

“The high yields of the drought-tolerant and pest-resistant chickpea, and the market value, meant that I am no longer seen as a poor widow but a successful farmer,” says Ethiopian farmer Temegnush Dabi.

“Ultimately, by making wealth out of chickpea and chickpea technologies in this country, people are starting to change their lives,” says Asnake. “They are educating their children to the university level and constructing better houses, even in towns. This will have a massive impact on the next generation.”

A similar success story is unfolding in Kenya, where GCP efforts during TLI led to the release of six new varieties of chickpea in the five years prior to GCP’s close at the end of 2014; more are expected to be ready within the next three years.

While chickpea is a relatively new crop in Kenya it has been steadily gaining popularity, especially in the drylands, which make up over 80 percent of Kenya’s total land surface and support nearly 10 million Kenyans – about 34 percent of the country’s population.

Photo: GCP

Drought tolerance experiments in chickpea at Egerton University, Njoro, Kenya.

“It wasn’t until my university went into close collaboration with ICRISAT during TLII and gained more resources and training options – facilitated by GCP – that chickpea research gained leverage in Kenya,” Paul Kimurto explains. “Through GCP and ICRISAT, we had more opportunities to promote the crop in Kenya. It is still on a small scale here, but it is spreading into more and more areas.”

Kenyan farmers are now discovering the benefits of chickpea as a rotational or ‘relay’ crop, he says, due to its ability to enhance soil fertility. In the highlands where fields are normally left dry and nothing is planted from around November to February, chickpea is a very good option to plant instead of letting fields stay fallow until the next season.

“By fixing nitrogen and adding organic matter to the soil, chickpeas can minimise, even eliminate, the need for costly fertilisers,” says Paul. “This is certainly enough incentive for cereal farmers to switch to pulse crops such as chickpea that can be managed without such costs.”

Households in the drylands have often been faced with hunger due to frequent crop failure of main staples, such as maize and beans, on account of climate change, Paul explains. With access to improved varieties, however, farmers can now produce a fast-growing chickpea crop between the harvest and planting of their main cereals. In the drylands they are now growing chickpeas after wheat and maize harvests during the short rains, when the land would otherwise lie fallow.

“Already, improved chickpeas have increased the food security and nutritional status of more than 27,000 households across the Baringo, Koibatek, Kerio Valley and Bomet areas of Kenya,” Paul says.

It is a trend he hopes will continue right across sub-Saharan Africa in the years to come, attracting more and more resource-poor farmers to grow chickpea.

Chickpea’s promise meeting future challenges

Beyond the end of GCP and the funding it provided, chickpea researchers are hopeful they will be able to continue working directly with farmers in the field, to ensure that their interests and needs are being addressed.

“To sustain integrated breeding practices post-2014, GCP has established Communities of Practice (CoPs) that are discipline- and commodity-oriented,” says Ndeye Ndack Diop, GCP’s Capacity Building Leader and TLI Project Manager. “The ultimate goal of the CoPs is to provide a platform for community problem solving, idea generation and information sharing.”

Ndeye Ndack has been impressed with the way the chickpea community has embraced the CoP concept, noting that Pooran has played an important part in this and the TLI projects. “Pooran was able to bring developing-country partners outside of TLI into the CoP and have them work on TLI-related activities. Being part of the community means they have been able to source breeding material and learn from others. In so doing, we are seeing these partners in Kenya and Ethiopia develop their own germplasm.

“Furthermore, much of this new germplasm has been developed by Master’s and PhD students, which is great for the future of these breeding programmes.”

“GCP played a catalytic role in this regard,” explains Rajeev Varshney. “GCP provided a community environment in ways that very few other organisations can, and in ways that made the best use of resources,” he says. “It brought together people from all kinds of scientific disciplines: from genomics, bioinformatics, biology, molecular biology and so on. Such a pooling of complementary expertise and resources made great achievements possible.”

Photo: A Paul-Bossuet/ ICRISAT

An Ethiopian farmer loads his bounteous chickpea harvest onto his donkey.

For Rajeev, the challenge facing chickpea research beyond GCP’s sunset is whether an adequate framework will be there to continue bringing this kind of community together.

“But that’s what we’re trying to do in the next phase of the Tropical Legumes Project (Tropical Legumes III, or TLIII), which kicks off in 2015,” explains Rajeev, who will be TLIII’s Principal Investigator. TLIII is to be led by ICRISAT.

“We will continue to work with the major partners as we did during GCP, which will involve, first of all, upscaling the activities we are doing now,” he says. “India currently has the capacity, the resources, to do this.”

Rajeev is hopeful that the relatively smaller national partners from Ethiopia and Kenya, and associated partners such as Egerton University, EIAR and maybe others, will have similar opportunities. “We hope they can also start working with their governments, or with agencies like USAID, and be successful at convincing them to fund these projects into the future, as GCP has been doing,” he says.

“The process is like a jigsaw puzzle: we have the borders done, and a good idea of what the picture is and where the rest of the pieces will fit,” he says.

Certainly for Paul Kimurto, the picture is clear for the future of chickpea breeding in Kenya.

“Improvements in chickpea resources cannot end now that new varieties have started entering farmers’ fields,” he says. “We’ve managed to develop a good, solid breeding programme here at Egerton University. The infrastructure is in place, the facilities are here – we are indeed equipped to maintain the life and legacy of GCP well beyond 2015.”

This can only be good news for lovers of the legume in India. With millions of smallholder farmers in Kenya and Ethiopia poised to exploit a ready market for new varieties that will change their families’ lives, chickpea’s potential for ensuring food security across the developing world seems more promising than ever.

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Mar 192015
 
Photo: N Palmer/CIAT

A farmer harvests her pearl millet crop in Ghana’s Upper West Region.

Pearl millet is the only cereal crop that can be grown in some of the hottest and driest regions of Asia and Africa. It is a staple provider of food, nutrition and income for millions of resource-poor people living on these harsh agricultural lands.

Even though pearl millet is well adapted to growing in areas characterised by drought, poor soil fertility and high temperatures, “there are limited genetic tools available for this orphan crop,” reported researcher Tom Hash at the International Crop Science Congress 10 years ago.

“The people who relied on this crop in such extreme environments had not benefitted from the ‘biotechnology revolution’, or even the ‘green revolution’ that dramatically increased food grain production on irrigated lands over a generation ago,” adds Tom, now Principal Scientist (Millet Breeding) in the Dryland Cereals Research Program of the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT). This lack of research dividends was despite the fact that pearl millet is the sixth most important cereal crop globally.

It was at this time – in 2005 – that the CGIAR Generation Challenge Programme (GCP) stepped up to invest in more genetic research for pearl millet (along with finger and foxtail millet).

Photo: S Mann/ILRI

Newly harvested pearl millet heads in Niger.

The use of genetic technologies to improve pearl millet had already made some advances through work carried out in the United Kingdom. The GCP initiative was established to improve food security in developing countries by expanding such available genetic work to create crops bred to tolerate drought, disease and poor soils.

With financial support from GCP, and with the benefit of lessons learnt from parallel GCP genetic research, ICRISAT scientists were able to develop more advanced tools for breeding pearl millet.

Pearl millet is used for food for humans and animals and is an essential component of dryland crop-livestock production systems like those of the Sahel region of Africa. It is a main staple (along with sorghum) in Burkina Faso, Chad, Eritrea, Mali, Niger, northern Nigeria, Senegal and Sudan. It has the highest protein content of any cereal, up to 22 percent, and a protein digestibility of about 95 percent, which makes it a far better source of protein than other crops such as sorghum and maize. Pearl millet grain is also a crucial source of iron and zinc. Pearl millet is the most widely grown millet (a general term for grain harvested from small-seeded grasses), and accounts for approximately 50 percent of the total world millet production. It has been grown in Africa and South Asia, particularly in India, since prehistoric times and was first domesticated in West Africa. It is the millet of choice in hot, dry regions of Asia, Africa and the Americas because it is well adapted to growing in areas characterised by drought, poor soil fertility and high temperatures; it even performs well in soils with high salinity or low levels of phosphorous. In short, thanks to its tolerance to harsh environments, it can be grown in areas where other cereals such as maize or wheat do not survive or do not yield well.

Protein in pearl millet ‘critical’ for nutrition

Photo: P Casier/ICRISAT HOPE

A farmer harvests millet in Mali.

Mark Laing, Director of the African Centre for Crop Improvement (ACCI) at the University of KwaZulu-Natal in South Africa, says the GCP-supported work on pearl millet will have long-term impacts.

He says it is the high protein content of pearl millet that makes it such a crucial crop for developing countries – in Africa, this is the reason people use pearl millet for weaning babies.

“It was interesting to us that African people have used pearl millet as a weaning food for millennia. The reason why was not clear to us until we assessed the protein content,” says Mark. “Its seed has 13–22 percent protein, remarkable for a cereal crop, whereas maize has only eight percent protein, and sorghum has only two percent digestible protein.”

Photo: S Kilungu/CCAFS

Pearl millet growing in Kenya.

Tom Hash agrees, adding: “More importantly, pearl millet grain has much higher levels of the critically important mineral micronutrients iron and zinc, which are important for neurological and immune system development.

“These mineral micronutrients, although not present in a highly available form, can improve blood iron levels when used in traditional pearl millet-based foods. Pearl millet grain, when fed to poultry, can provide a potentially important source of omega-3 fatty acids, which are also essential for normal neurological development.”

Pearl millet endowed with genetic potential

Photo: AS Rao/ICRISAT

A farmer with his pearl millet harvest in India.

In a treasure-trove of plant genetic resources, thousands of samples, or accessions, of pearl millet and its wild relatives are kept at ICRISAT’s gene banks in India and Niger.

For pearl millet alone, in 2004 ICRISAT had 21,594 types of germplasm in its vaults at its headquarters in India. This represents a huge reservoir of genetic diversity that can be mined for data and for genetic traits that can be used to improve pearl millet and other crops.

Between 2005 and 2007, with support from GCP, scientists from ICRISAT set to work to do just that, mining these resources for qualities based on observed traits, geographical origin and taxonomy.

Hari D Upadhyaya, Principal Scientist and Director of Genebank at ICRISAT, led the task of developing and genotyping a ‘composite collection’ of pearl millet. To do this, the team created a selection that reduced 21,594 accessions down to 1,021. This collection includes lines that are tolerant to drought, heat and soil salinity; others resistant to blast, downy mildew, ergot, rust and smut; and accessions resistant to multiple diseases.

Photo: C Bonham/Bioversity International

A traditional pearl millet variety growing in India.

The collection also includes types of pearl millet with high seed iron and zinc content (from traditional farmer varieties, or landraces, from Benin, Burkina Faso, Ghana and Togo), high seed protein content, high stalk sugar content, and other known elite breeding varieties.

The final collection comprised 710 landraces, 251 advanced breeding lines, and 60 accessions from seven wild species.

The GCP-supported scientists then used molecular markers to fingerprint the DNA of plants grown from the collection. Molecular markers are known variations in the sequence of the genetic code, found in different versions within a species, which act as flags in the genome sequence. Some individual markers may be associated with particular useful genes, but markers are useful even without known associations, as the different flags can be compared between samples. In the pearl millet research, scientists searched for similarities and differences among these DNA markers to assess how closely or distantly related the 1,021 accessions were to each other.

This was not only a big step forward for the body of scientific knowledge on pearl millet, but also for the knowledge and skills of the scientists involved. “The GCP work did make some significant contributions to pearl millet research,” says Tom, “mainly by helping a critical mass of scientists working on pearl millet to learn how to appropriately use the genetic tools that have been developed in better-studied fungi, plants and animals (including people).”

GCP extends know-how to Africa

Photos: N Palmer/CIAT

Comparisons of good and bad pearl millet yields in Ghana’s Upper West Region, which has suffered failed rains and rising temperatures.

The semiarid areas of northern and eastern Uganda are home to a rich history and culture, but they are difficult environments for successful food production and security.

In this region, pearl millet is grown for both commercial and local consumption. Its yields, although below the global average, are reasonable given that it is grown on poor sandy soils where other crops fail. Yet despite being a survivor in these harsh drylands, pearl millet can still be affected by severe drought and disease.

GCP helped kick-start work to tackle these problems. With financial support from GCP, and through ACCI, Geofrey Lubade, a scientist from Uganda, was able to study and explore breeding pearl millet that would be suitable for northern Uganda and have higher yields, drought tolerance and rust resistance.

Geofrey now plans to develop the best of his pearl millet lines for registration and release in Uganda, which he expects will go a long way in helping the resource-poor.

But Geofrey’s success is just one example of the benefits from GCP-support. Thanks to GCP, Mark Laing says that his students at ACCI have learnt invaluable skills that save significant time and money in the plant-breeding process.

“Many of our students, with GCP support, have been involved in diversity studies to select for desirable traits,” says Mark – and these students are now working on releasing new crop varieties.

He says that African scientists directly benefitted from the GCP grants for training in biotechnology and genetic studies.

Their work, along with that of a number of other scientists, will have a huge impact on plant breeding in developing countries – long term.

Photo: N Palmer/CIAT

A farmer inspects his millet crop in northwest Ghana.

As Mark explains, once breeders have built up a head of steam there is no stopping them. “Plant breeders take time to start releasing varieties, but once they get started, then they can keep generating new varieties every year for many years,” he says. “And a good variety can have a very long life, even more than 50 years.

“We have already had a significant impact on plant breeding in some African countries,” says Mark. But perhaps more importantly, he says, the work has changed the status of plant breeding and pearl millets as a subject: “It used to be disregarded, but now it is taken seriously as a way to have an impact on agriculture.”

For research and breeding products, see the GCP Product Catalogue and search for pearl millet.

Mar 102015
 

 

Niaba Témé

Niaba Témé

“I can’t talk enough about the positive stories from the Generation Challenge Programme [GCP]. It initiated something new. I cannot measure its benefits for my country, for myself and for the sorghum-breeding and -producer communities. Right now, GCP has reached its sunset; but for me it is a sunrise, because what we have been left with is so very important.”

Growing up in a farming community in Mali, on the southern edge of the Sahara Desert, plant breeder Niaba Témé knows the ups and downs of farming in the harsh, volatile semiarid regions of Africa.

“I used to love harvesting the millet and helping my mother with her groundnut crops,” he remembers fondly. “We grew other dryland crops too, like sorghum, cowpeas, Bambara nuts, sesame and dah.”

Niaba’s village of Yendouma-Sogol is one of many villages balanced along the edge of the Bandiagara escarpment – 150 kilometres of sandstone cliffs soaring hundreds of metres above the sandy plains below. The region is considered one of the most challenging places in the world to be a farmer. The climate is harsh, with the average daily temperature on the dry, sun-scorched plains rarely falling below 30°C and often exceeding 40°C during the hottest months of the year. With no major water source available for drinking, cropping and livestock husbandry, the threat of drought is ever-present here, as it is across much of Africa’s semiarid landscape.

While much of Mali’s irrigated agriculture relies on water from the River Niger, villages like Niaba’s depend entirely on the 500 or so millimetres of rainfall they receive during the July–August wet season. In the years that the rains didn’t come, Niaba’s family were unable to harvest anything at all. The repeated failure of his parents’ crops – coupled with a natural interest in science – inspired Niaba to embark on a career where he could help farming families like his own defend themselves against the risks of drought and extreme temperatures.

Photo: F Fiondella/CCAFS

Farmland in Diouna, Mali. Farmers here must contend with the Sahel’s dry, sandy soil and whatever limited rainfall the clouds bring to grow sorghum, millet, maize, and other crops.

Niaba’s journey

Niaba’s first big step along the research road was when he enrolled to study agronomy at Mali’s Institut Polytechnique Rural de Formation et de Recherche Appliquée in Eastern Bamako. Within two years he was offered a scholarship to study plant breeding at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) in Hyderabad, India. He then worked at the Cinzana Research Station in Mali.

Niaba later spent 11 years in the USA completing a bachelor’s degree, master’s degree and finally PhD in agronomy at Texas Tech University before returning home to Mali in 2007, where he was soon recruited by Mali’s Institut d’Économie Rurale (IER) to take charge of their new biotechnology lab at the Centre Régional de Recherche Agronomique.

His journey with the Generation Challenge Programme began in 2010 when IER received GCP funding to carry out sorghum research in Africa as part of GCP’s Sorghum Research Initiative (RI) launched that same year. The project was a collaboration with ICRISAT and France’s Centre de coopération internationale en recherche agronomique pour le développement (Agropolis–CIRAD; Agricultural Research for Development). With an initial focus on Mali, the project’s results would expand to encompass five other countries in the Sudano-Sahelian region: Burkina Faso, Ethiopia, Kenya, Niger and Sudan.

Sorghum the survivor gets even tougher

Photo: ICRISAT

Hand milling of sorghum grains – an arduous task, mostly carried out by poor women in the drylands of Africa.

Drought-hardy crops such as sorghum are ideal for Mali’s conditions, where more water-intensive crops such as maize simply cannot survive. Millions of poor rural people across Africa depend on sorghum in their day-to-day lives: it is eaten in many forms, used to make alcoholic beverages and as animal fodder, and is converted into biofuel for cooking.

But even sorghum has its limits. While the demand for it has doubled in West Africa in the last 20 years, productivity has generally remained low, with an average yield of only one tonne per hectare for traditional varieties in Mali. This is mostly due to post-flowering drought, poor soils and farming conditions, and limited access to quality, high-yielding seed. As rainfall patterns become increasingly erratic and variable across the world, scientists warn of the need to improve sorghum’s broad adaptability to drought, to ensure future food security in Africa.

The GCP Sorghum RI, with Niaba’s help, aimed to support the development of new breeds of sorghum that could survive better on less water in drought-stricken parts of Africa. It sought to improve sorghum yield and quality for African farmers and, in turn, improve the livelihoods and food security of communities across sub-Saharan Africa.

In 2012, Niaba found himself travelling once again, this time to Australia with IER colleague Sidi B Coulibaly. They spent three weeks working alongside, and training with, Andrew Borrell and his sorghum research team at the Queensland Government Department of Agriculture, Fisheries and Forestry’s (DAFF) Hermitage Research Facility in Warwick.

“We have been collaborating with researchers at DAFF and The University of Queensland since 2009, to introduce what is called the ‘stay-green’ drought-resistant gene into our local sorghum varieties,” says Niaba.

Photo provided by A Borrell

Left to right: Niaba Témé with David Jordan (Australia), Sidi B Coulibaly (Mali) and Andrew Borrell (Australia), visiting an experiment at Hermitage Research Facility in Queensland, Australia.

Niaba’s no longer green when it comes to using stay-green

Stay-green is a drought adaptation trait that allows sorghum plants to stay alive and maintain green leaves for longer during post-flowering drought. This means the plants can keep growing and produce more grain in drier conditions. It has contributed significantly to an increase in sorghum yields, using less water, in north-eastern Australia and southern USA for the last two decades.

GCP’s stay-green project aimed to evaluate the potential for introducing stay-green into Mali’s local sorghum varieties, enriching Malian pre-breeding material for the trait, and training African sorghum researchers, such as Niaba, in the methods of improving yields and drought resistance in sorghum breeding lines from both Australia and Mali.

Photo provided by E Weltzein-Rattunde

A sorghum farmer in Mali.

“In Australia we learnt about association mapping, population genetics and diversity, molecular breeding, crop modelling using climate forecasts, and sorghum physiology,” says Niaba.

Learning to use molecular markers was particularly exciting, he says, “because molecular markers make it easier to see if the plant being bred has the gene related to drought tolerance, without having to go through the lengthy process of growing the plant to maturity and risk missing the trait through visual inspection.”

Niaba says the molecular training he received in Australia complemented previous training he had received through a collaborative GCP-funded project with Agropolis–CIRAD and Syngenta Foundation for Sustainable Agriculture, in which he learnt to use molecular markers to identify and monitor key regions of sorghum’s genome in consecutive breeding generations through a process called marker-assisted recurrent selection (MARS).

A large part of GCP’s focus is building such capacity among developing country partners to carry out crop research and breeding independently in the future, so they can continue developing new varieties with drought adaptation relevant to their own environmental conditions.

“Our time in Australia was an intense but rewarding experience, more so for the fact that between the efforts of Australia and Mali, we have now developed new drought-tolerant crops which will enhance food security for my country,” says Niaba. “Similarly with the help of Agropolis–CIRAD and Syngenta, we are using molecular markers to improve breeding efficiency of sorghum varieties more adapted to the variable environment of Mali.”

Photo provided by A Borrell

Niaba (foreground) examining a sorghum panicle at trials in Mali in 2009.

Sorghum sunrise in Mali

On the back of the MARS project, Niaba successfully obtained GCP funding in 2010 to carry out similar research with Agropolis–CIRAD and collaborators in Africa at ICRISAT.

“In that project, we were trying to enhance sorghum grain yield and quality for the Sudano-Sahelian zone of West Africa using the backcross nested association mapping (BCNAM) approach,” explains Niaba. “This involved using an elite recurrent parent that is already adapted to local drought conditions. The benefit of this approach is that it can lead to detecting elite varieties much faster.”

The approach has the potential to halve the time it takes to develop local sorghum varieties with improved yield and adaptability to drought. The project developed 100 lines for 50 populations from backcrosses carried out with 30 recurrent parents. The lines are now being validated in Mali.

Photo: P St-Jacques/DFATD-MAECD

Agronomists inspect a field of sorghum in Mali.

Niaba says such successful collaborations and capacity development opportunities have been made possible only through GCP support.

“We had some contacts before, but we didn’t have the funds or skills to really get into a collaboration. Now we’re motivated and are making connections with other people so we can continue working with the material we have developed.

“GCP’s time may be ending, but it very much represents a new day – a sunrise for the work we are doing with sorghum here in Mali.”

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Photo: N Palmer/CIAT

Sorghum for sale.