Elizabeth Parkes grew up in Ghana as the youngest child and only girl in a middle-class family of nine children. Through visiting poor communities with her family, she began from an early age to build her understanding of the lives of resource-poor families in this part of West Africa and their need for reliable and nutritious food.
She also knows first-hand the important role women play on a farm and in a family. “Rural families are held together by women, so if you are able to change their lot, you can make a real mark,” says Elizabeth.
It was this sense of social conscience that drew her to a career in agricultural research: “My father, a Regional Education Officer, was not very amused; he thought agricultural research was a man’s job!” she recalls.
But Elizabeth was on a mission. “I see African communities where poverty and hunger are seemingly huge problems with no way out,” she says. “If I put in enough effort, I can bring some solutions. My primary target group is the less privileged, and women in particular have been my friends throughout. This sometimes means subtly getting the men to consider some changes in roles.”
This sense of destiny led to Elizabeth gaining a Bachelor’s degree in Agriculture, a Diploma in Education and a Master’s in Crop Science.
Meet Elizabeth in the complete podcast below (or see a playlist on PodOmatic) – and be inspired by her warmth and passion!
A worker in a Ghanaian cooperative producing garri, or gari, a kind of granular cassava flour used to prepare a range of foods.
Turning point: cassava to help the vulnerable
During a stint of national service between academic degrees, she was based in the tiny poor village of Aworowa in the Brong Ahafo Region. There was no electricity in her room, and the street lights came on once a week.
In a poor Ghanaian community everyone has to pitch in to the heavy daily round of chores.
“We all fetched water from the stream to drink and cook,” Elizabeth recalls. The plight of the villagers inspired Elizabeth to approach a scientist engaged in root and tuber projects at the Crops Research Institute (CRI) of Ghana’s Council for Scientific and Industrial Research (CSIR). She offered to carry out some research on cassava, hoping this might help the local people.
“I saw the struggle for households,” says Elizabeth. “I lived with them for one year, which transformed my interest and focus onto the vulnerable and less privileged.”
As a result, Elizabeth established CRI cassava trials in the region, and these trials continue today with Elizabeth still in touch with the villagers.
When her year of national service finished, Elizabeth was appointed as Assistant Research Officer at CRI – their first woman to be assigned to a research project. Already, she was beginning to fulfil her destiny.
Healthy cassava plants.
Challenges and opportunities
Unlike most crops, cassava is propagated, not by seed, but using cut sections of stem like these – just one of the many challenges this previously neglected crop offers breeders.
But cassava is not the easiest crop for a young researcher to cut their teeth on. It has long been regarded as an ‘orphan’ crop – one that researchers and funders have forgotten in their drive to work with the higher profile crops of wheat, rice and maize.
Cassava is a challenging crop for breeders to work with. “In addition to factors such as pests and disease, cassava is a long-season and very labour-intensive crop. It can take a whole year before you can expect to reap any rewards, and if you don’t have a strong team who can step in at different points throughout the breeding process, you can often find unexpected results at the end of it, and then you have to start all over again,” Elizabeth says.
But while many other young researchers gave up on with cassava, Elizabeth stuck with it, knowing the importance of this crop to farmers, especially women. And this is where Elizabeth’s involvement with the CGIAR Generation Challenge Programme (GCP) really started to make a difference to her future.
During GCP’s first research phase, Elizabeth’s path crossed with GCP scientist Martin Fregene, who encouraged Elizabeth to lead the Ghana partners involved in GCP’s cassava projects. She soon climbed the GCP research ranks, receiving multiple study grants, managing projects, and mixing and mingling with elite scientists. Along the way, Elizabeth also learnt new molecular breeding techniques. More recently, she was appointed Ghana’s lead researcher for GCP’s Phase II Cassava Research Initiative.
A place at the table, and sharing joy
Elizabeth Parkes examines a healthy crop of monster roots from an improved cassava variety.
Elizabeth believes the support GCP gave her to develop her skills and capacity is what has made a difference to her own and others’ destinies as research scientists: “GCP has made us visible and attractive to others; we are now setting the pace and doing science in a more refined and effective manner. I see GCP as the pace setters.
“GCP gave you the keys to solving your own problems and put structures in place so that knowledge learnt abroad could be transferred and applied at home.
“When I first joined GCP,” Elizabeth recalls, “I saw myself as somebody from a national research programme being given a place at the table; my inputs were recognised and what I said carried weight in decision-making.”
Elizabeth has attended three GCP Annual (later General) Research Meetings and won awards for her posters. “This greatly boosted my confidence,” she says. She is an active member of the Cassava Community of Practice – founded by GCP and now hosted by the Integrated Breeding Platform (IBP) – which facilitates and supports the integration of marker-assisted selection into cassava breeding. All this has accelerated Elizabeth’s quest to produce and disseminate farmer-preferred cassava varieties that are resistant to pests and diseases.
“With the Community of Practice you can call on other scientists; you share talk, you share ideas, you share joy. We share everything together,” Elizabeth enthuses. ‘Joy’ is a word that is often on Elizabeth’s lips when she describes the help that GCP has given her and others.
“We are all forever grateful to GCP and its funders. GCP has had a huge impact on research in Ghana, especially for cassava, rice, maize and yam. All the agricultural research institutes and individual scientists who came into contact with GCP have been fundamentally transformed.”
A farmer in Benin transforms cassava into garri, or gari, used as the basis of many different dishes.
In less than a decade, Elizabeth has become a valued researcher at CRI (currently on secondment at the International Institute of Tropical Agriculture, IITA) as well as Ghana’s leading GCP-supported scientist working on cassava. But in fulfilling her own destiny, she’s also passionate about helping others to achieve their potential.
“Building human capacity is my greatest joy,” she says. Farmers, breeders and a Ghanaian private-sector company are just a few of the fortunate beneficiaries of her expertise over recent years.
“Wherever I go, whatever opportunity I have, I refer back to GCP and its capacity-building work. You see, it’s good to release new plant varieties, but it’s also good to release people who will do the job.”
Nurturing women
Angelique Ipanga tends her cassava plants in the Democratic Republic of Congo. Cassava is often seen as a “women’s crop,” and the work of cultivating and preparing it falls largely on women’s shoulders.
Elizabeth talks about one of her favourite people, a farmer called Bea: “She’s very serious. She wants to learn more and she keeps expanding her farm.”
Bea hadn’t planted cassava before, so she pestered Elizabeth to find out more about how to do it properly. With Elizabeth’s guidance, Bea’s cassava-growing skills flourished, and she became so successful that she was recognised as the best farmer in her community.
“These are things that make me glad… that at least I have impacted somebody who hadn’t planted cassava before, and it’s amazing,” says Elizabeth. “There are people out there who need us, and when we give them our best, they will give the world their best as well.”
Elizabeth is also passionate about helping other women researchers: “I’ve pushed to make people recognise that women can do advanced agricultural science, and do it well. To see a talented woman researcher firmly established in her career and with her kids around her is thrilling.”
And so Elizabeth is now herself firmly established in world-class agricultural research, and further interesting stories are sure to follow.
“Before GCP we really struggled, but now everybody wants to have training in Ghana. Everybody wants to have something to do with us, and I will always say thank you to GCP for that, for making us attractive as researchers,” Elizabeth says.
“I’ve stuck with cassava because that’s my destiny! I may add other root and tuber crops, but cassava is my pivot.”
“There is a clear need to develop a range of varieties that meet diverse requirements”
For 30 years, Ousmane Boukar has been working towards a singular goal: to improve and secure cowpea production in sub-Saharan Africa.
“Cowpeas are very important in sub-Saharan Africa,” he says. “They are an important source of protein, and contribute to the livelihood and food security of millions.”
Despite their dietary importance, cowpea yields in Africa are low – on average a mere 10 to 30 percent of their potential. This is primarily because of attacks from insects and diseases, but is often further compounded by chronic drought.
Since 2007, Ousmane has worked for the International Institute of Tropical Agriculture (IITA) as cowpea breeder and Station Representative in Kano, Nigeria. As a breeder, his mission is to improve yields by identifying additional genetic sources of resistance to pests and diseases, tolerance of parasitic weeds, improved drought tolerance and adaptation to low soil fertility.
To accomplish this, he searches for genes associated with these kinds of valuable traits. He then uses this information to develop breeding populations comprising of plant lines with multiple useful traits, and works with farmers to grow these populations to make sure they do grow well in the field before releasing them as new varieties.
“Cowpea breeding is very challenging because of the range of production environments and cropping systems, and the diverse preferences among consumers and producers for grain, leaves, pods and fodder,” Ousmane says. “There is a clear need to develop a range of varieties that meet those diverse requirements, combining high yield potential and resistance to the major production constraints.”
A farmer’s field full of cowpea plants (with maize at the background) in Kano, Nigeria.
Joining an international programme
The same year Ousmane joined IITA, he joined forces in a new collaboration with cowpea breeders and geneticists from Burkina Faso, Mozambique, Senegal and the USA. He was Product Delivery Coordinator for the cowpea component of the Tropical Legumes I project (TLI) – a seven-year project funded by the CGIAR Generation Challenge Programme (GCP) that sought to use marker-assisted breeding techniques to breed high yielding, drought-tolerant and insect- and disease-resistant varieties of four important legumes.
Cowpea plants at podding stage.
“TLI has had a huge impact in Africa in terms of developing capacity to carry out marker-assisted breeding. This form of breeding helps us to breed new varieties in three to five years instead of seven to ten years.”
Key outcomes from the cowpea component of the project were a cowpea genome map and molecular markers that have helped breeders like Ousmane locate the genes in cowpeas that determine and regulate desirable traits. These markers can be used like flags to indicate which potential parent plants have useful genes, and which of the progeny from each cross have inherited them, making breeding more efficient.
“We have used this technology to develop advanced breeding lines that are producing higher yields in drier conditions and displaying resistance to several pests and diseases such as thrips [insects which feed on cowpeas] and Striga [a parasitic weed]. We expect these lines to be available to plant breeders by the end of 2015.”
Cowpea seed.
Ousmane says the success of the cowpea component of TLI owes much to the pre-existing relationships the partners had before the project. “TLI was an extension of a USAID collaborative project [Bean/Cowpea Collaborative Research Support Program] we had been working on since 2002,” he explains. “I had also crossed paths with breeders in Senegal, Burkina Faso and USA many times when I worked with the Institute of Agricultural Research for Development [IRAD] in Cameroon.”
Striga in a cowpea plot.
Ousmane was with IRAD in his home country of Cameroon from 1990 to 2007. He also worked by correspondence during this time to complete both his Master’s and Doctoral degrees in Plant Breeding and Genomics from the University of Purdue in Indiana, USA. His thesis involved characterising and mapping Striga resistance in cowpeas. Striga is a parasitic weed widespread in West Africa, which can reduce susceptible cultivar yields by up to 100 percent. Resistance within the host plant is the only practical control method (see ‘Cowpea in between’, GCP Partner and Product Highlights 2006, page 23).
A trader sells cowpeas in Moniya market, Ibadan, Nigeria.
Taking the lead in the Community of Practice
In 2011, in addition to his TLI and Product Delivery Coordinator roles, Ousmane became the coordinator of the Cowpea Community of Practice (CoP) – a newly created network founded by GCP to develop capacity in Africa and help GCP researchers share their new expertise in molecular breeding.
“The CoP was designed for cowpea researchers and people interested in cowpeas to ask questions and to share their expertise and knowledge, particularly with people who don’t have the experience, such as graduate students or breeders new to cowpeas,” Ousmane explains. Members are from Burkina Faso, Cameroon, Kenya, Malawi, Mali, Mozambique, Niger, Nigeria, Senegal, Tanzania and USA.
“My role as coordinator is to collect ideas, find funding opportunities, and understand member expertise and resources so I can direct members of the community to the right people.”
Ghanaian farmer Alanig Bawa drying cowpeas.
Ousmane says the position has opened his eyes to all the new research going on in cowpea. The number of new researchers in the field also heartens him. “There are more researchers that are practising molecular breeding than ever before, which is great, because we can enhance their impact and efficiency in cowpea breeding.”
As membership grows, Ousmane is confident that the community and capacity that have developed with help from GCP will remain sustainable after GCP’s close at the end of 2014. “Governments in Nigeria and Burkina Faso understand the importance of cowpeas and are investing in our research. As the set of skills and the number of personnel grow in other sub-Saharan countries, we are confident that cowpea research will expand and produce higher yielding varieties for their farmers.”
View Ousmane’s 2013 presentation from the GCP General Research Meeting: ‘Cowpea product catalogue and project status – Projects ongoing, completed, and to be continued post-2014’ (on SlideShare):
Young Nigerian scientists often leave Africa and look for jobs with international research agencies overseas. But with the CGIAR Generation Challenge Programme (GCP)-funded Cassava Research Initiative (RI), two young nationals have been leading the international collaboration and injecting confidence into Africa’s research capacity.
Leadership is a quality admired and consistently sought after, particularly when overcoming a challenge. Some leaders direct from afar; others rise through the ranks and work with their peers on the ground – winning respect from the people they lead as they get their hands dirty.
Dream team: Emmanuel Okogbenin (left) and Chiedozie Egesi (right), both of Nigeria’s National Root Crops Research Institute.
“If you want to work for the people, you have to walk with the people – that’s an African concept,” says Emmanuel Okogbenin, a plant breeder and geneticist at Nigeria’s National Root Crops Research Institute (NRCRI). “Then when you work with the people, you really understand what they want. When you speak, they know they can trust you.”
This powerful sentiment is one reason why GCP sought the collaboration of NRCRI in overcoming the challenge of sustaining Africa’s, and indeed the world’s, cassava production.
Having started as a small farm in 1923, NRCRI has taken giant strides to become one of Nigeria’s best research institutes, contributing immensely to the country’s economic development and making it the leading producer of cassava in the world. NRCRI Executive Director Julius Chukwuma Okonkwo says, “This would not have been attainable if not for the trust and support that GCP had in us when they made two of our young cassava researchers the leaders of an international collaboration.”
The two researchers to whom Julius refers are Emmanuel and his colleague Chiedozie Egesi, also a plant breeder and geneticist at NRCRI. Their combined 36 years’ of cassava research experience is matched by their passion to get the best out of Nigeria’s main staple crop.
And they are happy to get some dirt under their fingernails. “It’s just as important to work with the farmers in the field and understand what they want, as it is to do the research in the lab,” says Emmanuel. “At the end of the day we need to please the farmers, as they are the ones who will be using the new varieties that we are developing to sustain their livelihoods.”
Meet Chiedozie and Emmanuel in the video playlist below, learn more about cassava in Africa, and hear all about their research (or watch on Youtube):
Emmanuel explains that before GCP, “most African national programmes didn’t really have established crop-breeding programmes, and didn’t have the resources” to do the scale of research GCP assisted with. Nor did they have the capacity to use molecular-breeding techniques, which can potentially halve the time it takes to develop new varieties.
With help from GCP and CIAT, NRCRI was able to equip a new molecular-breeding laboratory, and staff were trained to incorporate molecular-breeding techniques into their breeding programme. “GCP was there not only to provide technology, but also to guide us in how to operate that technology,” explains Chiedozie.
Julius points out that both Chiedozie and Emmanuel were also influential in disseminating this knowledge and, in turn, building and sustaining NRCRI’s human capacity. “They both mentored many young scientists who have chosen a career in cassava and molecular breeding because of this.”
Transporting a bountiful cassava harvest from farm to market in Nigeria.
With training and infrastructure in place, NRCRI led an international collaboration that in 2010 released Africa’s first cassava variety developed using molecular-breeding techniques. Known as UMUCASS33 (or CR 41-10), it was resistant to cassava mosaic disease (CMD) – a devastating plant disease that can wipe out farmers’ entire cassava crops – and also highly nutritious. This was swiftly followed by a second similar variety, CR 36-5, and supplied to farmers.
Between this landmark release and GCP’s close in 2014, the cassava team had already released nearly 20 higher yielding, more nutritious varieties resistant to diseases and pests, and had begun working on developing drought-tolerant varieties.
These new and improved varieties – all generated as a direct or indirect result of his engagement in GCP projects – are, Chiedozie says, worth their weight in gold: “Through these materials, people’s livelihoods can be improved. The food people grow should be nutritious, resistant and high-yielding enough to allow them to sell some of it and make money for other things in life, such as building a house, getting a motorbike or sending their kids to school.” This social aspect is particularly pertinent in Nigeria, where these cassava varieties will have the greatest impact.
Feeding a giant
Nigerian farmer with his bountiful cassava harvest.
Nigeria is often referred to as the ‘Giant of Africa’. It is the most populous African country, with over 174 million inhabitants. The population’s main staple food is cassava, making Nigeria the world’s largest producer and consumer of the crop. At the same time, the country imports almost USD 4 billion of wheat every year – a figure that is expected to quadruple by 2030 if wheat consumption continues to grow at the same rate it is today.
The government is wary of this ‘overreliance’ on imported grain and is working towards making the country less reliant on wheat by imposing a wheat tariff. It also hopes to boost cassava production and commercialisation by promoting 20 percent substitution of cassava flour for wheat in breadmaking.
“The government feels that to quickly change the fortunes of farmers, cassava is the way to go,” explains Emmanuel, who liaises with the Nigerian Government to promote to farmers the benefit of cassava varieties with high starch concentrations. It is the flour from these varieties that is being used to partially replace wheat flour to make bread. GCP support has been crucial here too, in providing vital scientific information to the government. Emmanuel explains: “The tariff from wheat is expected to be ploughed back to support agricultural development – especially in the cassava sector – as the government seeks to increase cassava production to support flour mills.”
Cassava offers a huge opportunity to transform the agricultural economy, stimulate rural development and further improve Nigeria’s gross domestic product. In 2014, Nigeria’s economy surpassed that of South Africa’s to become the largest on the continent. By 2050, Nigeria is expected to rise further and become one of the world’s top 20 economies.
Unfortunately, however, like many growing economies worldwide, Nigeria is still working to address severe inequality, including in the distribution of wealth and in feeding the country’s expanding population.
A woman with her children at work in a cassava processing centre in Nigeria.
It’s a problem Chiedozie understands well: “Nigeria is an oil-producing country, but you still see grinding poverty in some cases,” he says. “Coming from a small town in the southeast of the country, I grew up in an environment where you see people who are struggling, weak from disease, poor, and with no opportunities to send their children to school,” he reveals. The poverty challenge, he explains, hits smallholder farmers particularly hard: “Urban development caught up with them in the end: some of them don’t even have access to the land that they inherited, so they’re forced to farm along the street.”
For Chiedozie, the seemingly bleak picture only served to ignite a fierce determination and motivation to act: “Despite the social injustice around me, I always thought there was opportunity to improve people’s lives.” And thus galvanised by the plight of Nigerian farmers, Chiedozie promptly shelved his plans for a career in medical surgery and pursued biological sciences and a PhD in crop genetics, a course he interspersed with training stints in the USA at Cornell University and the University of Washington, before returning to his homeland to accept a job as head of the cassava breeding team, and – following a promotion in 2010 – to become Assistant Director of the Biotechnology Department at NRCRI.
Empowering African researchers
Carrying cassava at a processing centre in Nigeria.
Emmanuel, who followed a similar educational route to Chiedozie, says both he and his colleague are exceptions to the norm in Africa, where African researchers tend to look for opportunities at international or private institutes rather than in national breeding programmes.
“It is difficult being a researcher in Africa,” says Emmanuel. “We don’t get paid as much as breeders in more developed countries, and funding is very hard to obtain.”
Emmanuel says his proudest moment was when GCP was looking for Africans to take up leadership roles. “They felt we could change things around and set a precedent to bring people back to the continent,” he says. “They appreciated our values and the need to install African leaders on the ground in Africa rather than in Europe, Asia or the Americas.”
Jean-Marcel Ribaut, GCP’s Director, says that seeking this local leadership was a novel approach for a transnational programme like GCP at the time, and proved to be an imperative feature for all GCP Research Initiatives. “The reasoning behind the approach is two-fold: Firstly, it’s important that our national partners share in feeling ownership of the projects and outcomes; secondly, they are gaining experience in the role so they can continue to do so after the close of the Programme in 2014,” he says. “We feel that most of our leading institutes, NRCRI included, are in a better position now than when they joined the project, and that this, along with their experience, has already gained them more exposure and funding opportunities.”
This is indeed true of the NRCRI cassava team, which is engaging with the Bill & Melinda Gates Foundation, Cornell University, IITA and Uganda’s National Crop Resources Research Institute in an initiative that Chiedozie promises will be at the front of cutting-edge technology. “We are still working out specifics, but it will see us continuing to use marker-assisted breeding techniques to develop higher yielding, stress-tolerant cassava varieties.”
Chiedozie adds this would not have been possible without GCP, which helped them to develop their capacity in Nigeria and in Africa, and this has “created a confidence in other global actors, who, on seeing our ability to deliver results, are choosing to invest in us.”
Before GCP came along, cassava was something of an orphan crop in agricultural research. Among the challenges to efficient breeding of cassava are that it is slow to grow and is propagated, not by seed, but using cut sections of stem like those shown. But with investment and capacity building from GCP, particularly in molecular breeding tools, African cassava scientists have gained a new confidence and prestige.
Continuing the momentum
One organisation that has been impressed by the work done at NRCRI is the CGIAR Research Program on Roots, Tubers and Bananas (RTB). RTB Director Graham Thiele has been following the work done at NRCRI since 2010 with great interest. “We have been really impressed to see a national programme like NRCRI playing a leading role in these successful GCP projects, and grow as a result of this,” he says.
One area of research that has particularly impressed Graham is Chiedozie and Emmanuel’s pre-emptive breeding for cassava brown streak disease (CBSD) resistance. “CBSD isn’t currently an issue in Nigeria but it has the potential to wipe out all crops, as it has in Uganda and Tanzania, if it continues to spread west from these countries,” he explains.
“What Chiedozie and Emmanuel are doing is using molecular markers, developed in collaboration with IITA, to search for genes in their varieties that confer resistance to brown streak virus. They can then use these when breeding for CBSD resistance without exposing cassava to the virus. It’s very exciting and forward thinking, as normally people breed for resistance only when the disasters happen.”
As GCP approached its sunset in December 2014, Chiedozie and Emmanuel were reaching out to RTB to seek funding to continue this and other projects they are currently working on. “They’ve already created some great varieties but have plenty more in the pipeline, so we want to help them finish this work and, most importantly, keep the momentum going,” says Graham.
Chiedozie looks forward to the next steps with optimism, confirming that the new collaboration will continue in the quest to “give African farmers varieties of cassava that they will love to grow.”
Beyond the glittering coastline of what was once known as the Gold Coast, Ghana’s shrublands and rich forested hills are split by forking rivers that reach inland through the country’s lush tropics, into drier western Africa. In the past 40 years, seven major droughts have battered the people of Africa – with the most significant and devastating occurring in the Sahel region and the Horn of Africa in the early 1970s and 1980s.
This little girl in Kenya already seems to know that cassava roots are precious.
But despite the massive social disruption and human suffering that these droughts cause, life goes on. In south-eastern Ghana and in Togo, the three-million-plus people who speak the Ewe language have a word for this. It is agbeli: ‘There is life’. It is no coincidence that this word is also their name for a tropical and subtropical crop that survives through the worst times to feed Africa’s families: cassava.
Cassava is a lifeline for African people, and is a particularly important staple food for poorer farmers. More cassava is produced in Africa than any other crop, and it is grown by nearly every farming family in sub-Saharan Africa, supplying about a third of the region’s daily energy intake. In the centuries since Portuguese traders introduced this Amazonian plant to Africa, cassava has flourished, yielding up to 40 tonnes per hectare.
Hear more on just why cassava is so important to food security from Emmanuel Okogbenin, of Nigeria’s National Root Crops Research Institute, in the video below (or watch on Youtube):
African countries produced nearly 140 million tonnes of cassava in 2012 – but most of the production is subsistence farming by small-scale farmers. Even the undisputed global cassava giant, Nigeria, currently produces only just enough to feed its population – and although the country is increasingly moving towards production of cassava for export as an industrial raw material, the poorest farmers often do not produce enough to sell, or have access to these markets.
Because cassava does so well on poor soils, on marginal land and with little rainfall, it can outlast its more sophisticated crop competitors: wheat, rice and maize. In fact, under harsh conditions such as drought, the amount of energy a given area of cassava plants can produce in the form of starchy carbohydrates outstrips all other crops. Chiedozie Egesi, a plant breeder and geneticist at Nigeria’s National Root Crops Research Institute (NRCRI), describes cassava as “the crop you can bet on when every other thing is failing”.
Despite cassava’s superhero cape, however, there’s no denying that its production is not at its highest when faced with diseases, pests, low-nutrient soils and drought. How plants deal with problems like low nutrients or dry conditions is called ‘stress tolerance’ by scientists. Improving this tolerance – plus resistance to diseases and pests – is the long-term goal for staple crops around the world so that they have higher yields in the face of capricious weather and evolving threats.
In the 1980s, catastrophe struck cassava production in East and Central Africa. A serious outbreak of cassava mosaic disease (CMD) – which first slowly shrivels and yellows cassava leaves, then its roots – lasted for almost 15 years and nearly halved cassava yields in that time. Food shortages led to localised famines in 1993 and 1997.
Other diseases affecting cassava include cassava brown streak disease (CBSD), cassava bacterial blight, cassava anthracnose disease and root rot. CBSD is impossible to detect above ground. Its damage is revealed only after harvest, when it can be seen that the creeping brown lesions have spoilt the white flesh of the tubers, rendering them inedible. Many cassava diseases are transmitted through infected cuttings, affecting the next generation in the next season. Pests that also prey on cassava include the cassava green mite and the variegated grasshopper.
Between the effects of drought, diseases, pests and low soil nutrients, cassava yields vary widely – losses can total between 50 and 100 percent in the worst times.
Symptoms of cassava mosaic disease (CMD) and cassava brown streak disease (CBSD), both of which can cripple cassava yields.
GCP takes the first steps to kick start cassava research
The next step forward for cassava appeared to be research towards breeding stronger and more resilient cassava varieties. However, cassava research had long been neglected – scientists say it’s a tricky crop that has garnered far less policy, scientific and monetary interest than the comparatively glamorous crops of maize, rice and wheat.
Watch as Emmanuel tells us more about the complexities and challenges of cassava breeding in the video below (or on YouTube):
Cassava is a plant which ‘drags its feet’: creating new plants has to be done from cuttings, which are costly to cut and handle and don’t store well; the plant takes up to two years to grow to maturity; and it is onerous to harvest. Elizabeth Parkes, of Ghana’s Crops Research Institute (CRI) (currently on secondment at the International Institute of Tropical Agriculture, IITA), says the long wait can be difficult.
This is where the work of scientists funded by the CGIAR Generation Challenge Programme (GCP) came in. Plant breeder and molecular geneticist Emmanuel Okogbenin of NRCRI led the cassava research push launched in 2010. He explains that before GCP, “most national programmes didn’t really have established crop breeding programmes, and didn’t have the manpower” to do the scale of research GCP supported.
Usually, researchers looking to breed crops that are more resistant to drought, diseases and pests would use conventional breeding methods that could take considerable time to deliver any results, especially given cassava’s slow path to maturity. Researchers would be trying to select disease- and pest-resistant plants by looking at how they’re growing in the field, without any way to see the different genetic strengths each plant has.
An IITA researcher exams cassava roots in the field.
This is where new ‘molecular breeding’ tools are particularly useful, given that – genetically – cassava presents more of a challenge to breeders than its cereal counterparts. Like many other vegetatively propagated crops, cassava is highly heterozygous, meaning that the counterpart genes on paired chromosomes tend to be different versions, or alleles, rather than the same. This makes it difficult to identify good parent plants for breeding and, after these are crossed, to accurately select progeny with desired traits. Useful – or detrimental – genes can be present in a cassava plant’s genetic code but not reflected in the plant itself, making breeding more unpredictable – and adding extra obstacles to the hunt for the exact genes that code for better varieties of cassava.
Although late to the world of molecular breeding, cassava had not missed its chance. Guided by GCP’s ambitious remit to increase food security through modern crop breeding, GCP-supported scientists have applied and developed molecular breeding methods that shorten the breeding process by identifying which plants have good genes, even before starting on that long cassava growth cycle. Increasing the capacity of local plant breeders to apply these methods has great potential for delivering better varieties to farmers much faster than has traditionally been the case.
Charting cassava’s genetic material was the first step in the researchers’ molecular quest. Part of the challenge for African and South American researchers was to create a genetic map of the cassava genome. Emmanuel describes the strong foundation that these early researchers built for those coming after: “It was significant when the first draft of the cassava genome sequence was released. It enabled rapid progress in cassava research activities and outcomes, both for GCP and cassava researchers worldwide.”
Cassava on sale in Kampala, Uganda.
Once cassava’s genome had been mapped, the pace picked up. In just one year, GCP-supported scientists phenotyped and genotyped more than 1000 genetically different cassava plants – that is, measured and collected a large amount of information about both their physical and their genetic traits – searching for ‘superstar’ plants with resistance to more than one crop threat. During this process, scientists compare plant’s physical characteristics with their genetic makeup, looking for correlations that reveal regions of the DNA that seem to contain genes that confer traits they are looking for, such as resistance to a particular disease. Within these, scientists then identify sequences of DNA, or ‘molecular markers’, associated with these valuable genes or genetic regions.
Plant breeders can use this knowledge to apply an approach known as marker-assisted selection, choosing their breeding crosses based directly on which plants contain useful genes, using markers like tags. This makes producing better plant varieties dramatically faster and more efficient. “It narrowed the search at an early stage,” explains Emmanuel, “so we could select only material that displayed markers for the genetic traits we’re looking for. There is no longer any need to ship in tonnes of plant material to Africa.”
Like breadcrumbs leading to a clue, breeders use markers to lead to identifying actual genes (rather than just a site on the genome) that give certain plants desirable characteristics. However, this is a particularly difficult process in cassava. Genes are often obscured, partly due to cassava’s highly heterozygous nature. In trials in Africa, where CMD is widespread, resistant types were hard to spot when challenged with the disease, and reliably resistant parents were hard to pin down.
This meant that two decades of screening cassava varieties from South America – where CMD does not yet exist yet – had identified no CMD-resistance genes. But screening of cassava from Nigeria eventually yielded markers for a CMD-resistance gene – a great success for the international collaborative team led by Martin Fregene, who was based in Colombia at the International Center for Tropical Agriculture (CIAT).
This finding was a win for African plant breeders, as it meant they could use molecular breeding to combine the genes producing high-quality and high-yielding cassava from South America with the CMD-resistance gene found in cassava growing in Nigeria.
Chiedozie Egesi, who led the work on biotic trait markers, explains the importance of combining varieties from South America with varieties from Africa: “Because cassava is not native to Africa, those varieties are not as genetically diverse, so we needed to bring genetic diversity from the centre of origin: South America. Coupling resistance genes from African varieties with genes for very high yields from South America was critical.”
Cassava research leaps forward with new varieties to benefit farmers
GCP’s first investment phase into cassava research stimulated a sturdy injection of people, passion, knowledge and funds into the second phase of research. From the genome maps created during the first phase, some of the world’s best geneticists would now apply genomic tools and molecular breeding approaches to increase and accelerate the genetic gains during breeding, combining farmers’ favourite characteristics with strong resistances and tolerances to abiotic and biotic constraints.
In the sprawling, tropical city of Accra on Ghana’s coast, the second phase of the research was officially launched at the end of the wet season in mid-2010. NRCRI’s Emmanuel Okogbenin coordinated product delivery from the projects, but the roles of Principal Investigator for the different projects were shared between another four individuals.
These were breeder and geneticist Chiedozie Egesi (NRCRI, Nigeria), molecular geneticist Morag Ferguson (IITA), genomic scientist Pablo Rabinowicz (University of Maryland, USA) and physiologist and geneticist Alfredo Alves (Brazilian Corporation of Agricultural Research, EMBRAPA). The team shared the vision of enabling farmers to increase cassava production for cash, well beyond subsistence levels.
Garri, or gari, a kind of granular cassava flour used to prepare a range of foods.
If the Accra launch set the stage for the next five years of cassava collaboration, a breakthrough in Nigeria at the end of 2010 set the pace, with the release of Africa’s first cassava variety developed using molecular-breeding techniques. “It was both disease-resistant and highly nutritious – a world-first,” recalls Emmanuel proudly.
Known as UMUCASS33 (or CR41-10), it took its high yield and nutritional value from its South American background, and incorporated Nigerian resistance to devastating CMD attacks thanks to marker-assisted selection. It was also resistant to several other pests and diseases. UMUCASS33 was swiftly followed by a stream of similar disease-busting varieties, released and supplied to farmers.
Never before had cassava research been granted such a boost of recognition, scientific might and organisational will. And never before had there been so much farmer consultation or so many on-farm trials.
“Cassava was an orphan crop and with the help of GCP it is becoming more prominent,” says Chiedozie. “GCP highlighted and enhanced cassava’s role as a major and reliable staple that is important to millions of poor Africans.”
Another important challenge for scientists was to develop a higher-yielding cassava for water-limited environments. The aim was to keep mapping genes for resistance to other diseases and pests and then combine them with favourable genetics that increase yield in drought conditions – no easy feat. Drought’s wicked effect on cassava is to limit the bulk of the tuber, or sometimes to stop the tuber forming altogether. Emmanuel led the work on marker-assisted recurrent selection for drought.
Hear from Chiedozie on the beneficial outcomes of GCP – in terms not only of variety releases but also of attracting further projects, prestige, and enthusiastic young breeders – in the video below (or on YouTube):
Many traits and many varieties
As closely as the cassava teams in Africa were working together, Chiedozie recalls that each country’s environment demanded different cassava characteristics: “We had to select for what worked best in each country, then continue with the research from there. What works fine for East Africa may not be so successful in Nigeria or Ghana”. A core reference set representing most of the diversity of cassava in Africa was improved with the addition of over 564 varieties. Improving the reference set, says project leader Morag Ferguson, “enables the capture of many diverse features of cassava” within a relatively small collection, providing a pathway for more efficient trait and gene discovery.
While mapping of cassava’s genetic makeup carried on, with a focus on drought tolerance, researchers continued to develop a suite of new varieties. They mapped out further genes that provided CMD resistance. In Tanzania, four new varieties were released that combined resistance to both CMD and CBSD – two for the coastal belt and two for the semi-arid areas of central Tanzania. These new varieties had the potential to double the yield of existing commercial varieties. In Ghana too, disease-resistant varieties were being developed.
Built-in disease resistance can make a huge difference to the health of cassava crops. This photo shows a cassava variety resistant to African cassava mosaic virus (ACMV), which causes cassava mosaic disease (CMD), growing on the left, alongside a susceptible variety on the right.
Meanwhile in Nigeria, another variety was released in 2012 with very high starch content – an essential factor in good cassava. This is a critical element to breeding any crop, explains Chiedozie: “A variety may be scientifically perfect, based on a researcher’s perspective, but farmers will not grow it if it fails the test in terms of taste, texture, colour or starchiness.”
Geoffrey Mkamilo, cassava research leader at Tanzania’s Agricultural Research Institute, Naliendele, says that farmer awareness and adoption go hand in hand. Once they had the awareness, he says, “the farmers were knocking on our doors for improved varieties. They and NGOs were knocking and calling.”
After groundwork in Ghana and Nigeria to find potential sources of resistance, cassava varieties that are resistant to bacterial blight and green mites were also developed in Tanzania and then tested. By the time GCP closed in December 2014, these varieties were on their way to commercial breeders for farmers to take up.
Scientists seeking to resolve the bigger challenge of drought resistance have achieved significant answers as well. Researchers have been able to map genetic regions that largely account for how well the crops deal with drought.
Hunt for ‘super powered’ cassava
The hunt was on for drought-tolerance genes in African cassava plants. The end goal was to find as many different drought-related genes as possible, then to put them all together with the applicable disease and pest resistance genes, to make a ‘super powered’ set of cassava lines. Molecular breeders call this process ‘pyramiding’, and in Ghana, Elizabeth Parkes led these projects.
With the help of Cornell University scientists, the researchers compared plants according to their starch content, how they endured a dry season, how they used sunlight and how they dealt with pests and diseases.
Fourteen gene regions or quantitative trait loci (QTLs) were identified for 10 favourable traits from the genetic material in Ghana, while nine were found for the plants in Nigeria – with two shared between the plants from both Ghana and Nigeria. After that success, the identified genes were used in breeding programmes to develop a new generation of cassava with improved productivity.
Pyramiding is important in effective disease resistance; Chiedozie explains in the video below (or on YouTube):
New cassava varieties rich in pro-vitamin A have a telltale golden hue.
The research has also delivered results in terms of Vitamin A levels in cassava. In 2011, the NRCRI team, together with IITA and HarvestPlus (another CGIAR Challenge Programme focussed on the nutritional enrichment of crops), released three cassava varieties rich in pro-vitamin A, which hold the potential to provide children under five and women of reproductive age with up to 25 percent of their daily vitamin A requirement. Since then, the team has aimed to increase this figure to 50 percent. In 2014, they released three more pro-vitamin A varieties with even higher concentrations of beta-carotene.
A field worker at IITA proudly displays a high-yielding, pro-vitamin A-rich cassava variety (right), compared with a traditional variety (left).
The new varieties developed with GCP support are worth their weight in gold, says Chiedozie: “Through these varieties, people’s livelihoods can be improved. The food people grow should be nutritious, resistant and high-yielding enough to allow them to sell some of it and make money for other things in life, such as building a house, getting a motorbike or sending their kids to school.”
Turning from Nigeria to Tanzania, Geoffrey has some remarkable numbers. He says that the national average cassava yield is 10.5 tonnes per hectare. He adds that a new cassava variety, PWANI, developed with GCP support and released in 2012, has the potential to increase yields to 51 tonnes per hectare. And they don’t stop there: the Tanzanian researchers want to produce three million cuttings and directly reach over 2,000 farmers with these new varieties, then scale up further.
A farmer tends her cassava field in northern Tanzania.
Cassava grows up: looking ahead to supporting African families
Emmanuel reflects on how the first release of a new disease-resistant high-yielding cassava variety took fundamental science towards tangible realities for the world’s farmers: “It was a great example of a practical application of marker technology for selecting important new traits, and it bodes well for the future as markers get fully integrated into cassava breeding.”
Emmanuel further believes that GCP’s Cassava Research Initiative has given research communities “a framework for international support from other investors to do research and development in modern breeding using genomic resources.” Evaluations have demonstrated that molecular-assisted breeding can slash between three and five years from the timeline of developing better crops.
Women tend to bear most of the burden of cassava cultivation and preparation. Here a Congolese woman pounds cassava leaves – eaten in many regions in addition to cassava roots – prior to cooking a meal for her family.
But, like cassava’s long growth cycle underground, Emmanuel knows there is still a long road to maturity for cassava as a crop for Africa and in research. “Breeding is just playing with genetics, but when you’re done with that, there is still a lot to do in economics and agronomics,” he says. Revolutionising cassava is about releasing improved varieties carefully buttressed by financial incentives and marketing opportunities.
Rural women in particular stand to benefit from improved varieties – they carry most of the responsibility for producing, processing and marketing cassava. So far, Elizabeth explains: “Most women reported an increase in their household income as a result of the improved cassava, but that is still dependent on extra time spent on cassava-related tasks” – a burden which she aims to diminish.
Elizabeth emphasises that future improvement research has to take a bottom-up approach, first talking to female farmers to ensure that improved crops retain characteristics they already value in addition to the new traits. “Rural families are held together by women, so if you are able to change their lot, you can make a real mark,” she says. Morag echoes this hope: “We are just starting to implement this now in Uganda; it’s a more farmer-centric approach to breeding”. The cassava teams emphasise the importance of supporting women in science too; the Tanzanians teams are aiming for a target of 40 percent women in their training courses.
Meet Elizabeth in the podcast below (or on PodOmatic), and be inspired by her passion when it comed to women in agriculture and in science:
This direct impact goes much further than individuals, says Chiedozie. “GCP’s daring has enabled many national programmes to be self-empowered, where new avenues are unfolding for enhanced collaboration at the local, national and regional level. We’re seeing a paradigm shift.” And Chiedozie’s objectives reach in a circle back to his compatriots: “Through GCP, I’ve been able to achieve my aims of using the tools of science and technology to make the lives of poor Africans better by providing them with improved crops.”
GCP has been crucial for developing the capacity of countries to keep doing this level of research, says Chiedozie: “The developing-country programmes were never taken seriously,” he says. “But when the GCP opportunity to change this came up we seized it, and now the developing-country programmes have the boldness, capacity and visibility to do this for themselves.”
Emmanuel says his proudest moment was when GCP was looking for Africans to take up leadership roles. “They felt we could change things around and set a precedent to bring people back to the continent,” he says. “They appreciated our values and the need to install African leaders on the ground in Africa rather than in Europe, Asia or the Americas.”
“If you want to work for the people, you have to walk with the people – that’s an African concept. Then when you work with the people, you really understand what they want. When you speak, they know they can trust you.” GCP trusted and trod where others had not before, Chiedozie says.
Elizabeth agrees: “In the past, the assumption was always that ‘Africa can’t do this.’ Now, people see that when given a chance to get around circumstances – as GCP has done for us through the provision of resources, motivation, encouragement and training – Africa can achieve so much!”
More links
Profiles here on the Sunset Blog: Elizabeth’s story | Chiedozie’s story
And an extra Sunset helping of cassava in the stories of our partnerships: ARI, Tanzania | CRI, Ghana | NRCRI, Nigeria
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.”
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.
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.
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.
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.
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.”
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
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.
A farmer carefully packs harvested cassava tubers for transportation to the market in Bungu, Tanzania.
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.”
Sorghum 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.
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.
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 tô (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.
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
“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.
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.
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.”
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.
“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.”
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.”
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.
“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
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.”
For 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.”
Hei Leung has always been passionate about diversity, especially genetic diversity, and that’s one reason why he leapt at the chance to get involved with the CGIAR Generation Challenge Programme (GCP) right from its inception more than a decade ago.
But GCP’s attraction for Hei wasn’t just about genetic diversity; it was also about working with diverse institutes and researchers. At the time, Hei had been working for the International Rice Research Institute (IRRI) for some 10 years, on and off, including a stint at Washington State University in the USA.
“The whole idea of the Challenge Programme was to bring people together from different places instead of an individual CGIAR Centre doing things,” he says.
Hei also saw the likely spin-offs from rice research to other crops such as wheat, maize and sorghum, which are also crucial to food security.
“Rice is a ‘model crop’ because of its small genome. This means researchers in major cereals like wheat and maize, which have much bigger genomes but share genes of similar functions, can benefit from our work with rice.”
From little pizzas great programmes grow!
It all began in 2003, over pizza, in Rome. Hei remembers that his commitment to GCP started when he met with a small group of people including Robert Zeigler, who was to become the first Director of GCP, and who is currently Director General of IRRI.
“Little did we know that pizza was so inspiring,” Hei says, recalling that it was during that meeting that they agreed on the name: the Generation Challenge Programme.
GCP was formally launched in 2004 in Brisbane, Australia, at the 4th International Crop Science Congress.
Making the Programme ‘pro-poor’
Hei was initially involved with GCP as Subprogramme Leader for Comparative Genomics for Gene Discovery between 2004 and 2007, and later as a Principal Investigator for the Rice Research Initiative. Taking on his leadership role, Hei recognised from the start that many crops important to developing communities in Asia and Africa needed to become more drought-tolerant because of the increasing effects of climate change.
“We wanted to have a programme that is what we call ‘pro-poor’,” he says. “The majority of the world’s people depend on crops such as rice, wheat and maize for food.”
“I always feel that if you can solve eastern India’s problems, you can solve most of the problems in the world,” Hei adds. “If you travel in eastern India, you can see climate change happening day in, day out. You don’t have to wait 10 years or 50 years; it’s happening already. They either have too much or too little water. It’s a high-stress environment.”
Women at work threshing rice near Sangrur, Punjab, India.
Rice is the world’s most widely consumed cereal crop, and is particularly important as the staple food of 2.4 billion people in Asia. GCP recognised rice’s importance and invested almost USD 29.5 million in rice research and development.
Furthermore, the genetic breeding lessons learnt from rice can also be applied to other staple crops such as wheat, maize and sorghum.
They found sorghum and maize varieties that contained genes, similar to rice’s PSTOL1, that also conferred tolerance to phosphorus-deficient soils by enhancing the plant’s root system. They were then able to develop molecular markers to help breeders in Brazil and Africa to identify lines with these genes, which can now be used in breeding and developed as varieties for farmers growing crops, particularly in acidic soils.
Seeing the potential for novel researcher interactions
Hei also recognised that crops that received less scientific attention but remained important as regional staple foods, such as bananas and plantains (of the genus Musa), could benefit from comparative genomics research.
“We had a highly motivated group of researchers willing to devote their efforts to Musa,” remembers Hei, who is currently IRRI Program Leader of Genetic Diversity and Gene Discovery.
“GCP’s community could offer a framework for novel interactions among banana-related actors and players working on other crops, such as rice. So, living up to its name as a Challenge Programme, GCP decided to take the gamble on banana genomics and help it fly.”
A banana farmer at work in the Philippines.
However, after four years, Hei found it difficult to maintain his GCP leadership role as well as keep on top of his IRRI work: “They said I was 50 percent with IRRI and 50 percent with GCP, but it is never like that in reality. I was always doing two jobs, or at least one-and-a-half jobs, and I didn’t think I was doing a good enough job for either. I thought it was time for other people to come into GCP.”
While Hei stepped down from a leadership role, he remained active working on GCP projects throughout the life of the Programme.
Hei says that during the last five years of GCP, a lot of technology to characterise genetic diversity evolved “to bring high-quality science to accelerate our mission to help the poor areas of Asia and Africa.”
A MAGIC affair
The development of MAGIC (multi-parent advanced generation intercross) populations is the project that Hei gets most excited about. From these populations, created by crossing different combinations of multiple parents, plant lines can be selected that have useful characteristics such as drought tolerance, salinity tolerance and the ability to produce better quality grain.
“Now many crop breeders are calling for MAGIC populations,” says Hei. “I feel proud that at GCP we decided to support this concept and activity. This is one of GCP’s most important legacies and it’s one of my most favourite things.”
Hei Leung looking relaxed in the lab at IRRI.
Honoured as a Fellow of the American Phytopathological Society (APS), Hei is recognised “for his leadership in the international community toward building and distributing rice genetic and genomic resources and creating capacity in plant pathology in the developing countries of Asia.”
Hei’s GCP leadership and research have clearly provided him with an important platform for taking on leadership and champion roles linking many individuals and organisations across Asia and Africa. His ASP profile concludes: “His promotion of collaborative research and his leadership in such programmes in the developing world have contributed to the building of a dynamic research community that promotes both basic knowledge and food security for Asia and the world.”
Making a difference to food security and farmer’s lives in developing countries is what GCP is all about. Such differences have been made possible through collaborative links that connect a diversity of organisations and people with the latest research in genetic diversity and breeding techniques.
A farmer transplants rice in the Philippines.
It’s amore!
Hei recalls his personal and professional journey with GCP with much affection: “I think that it has been a wonderful scientific journey in terms of knowing the science and opening up my mind to being more receptive to alternative ways of doing things.
“There have been so many friends I have met through networking with GCP. Sometimes you go through bumpy roads, but anything you do will have bumpy times. And it’s very unusual to have a programme so illuminating. We honoured our commitment to finish in 10 years. It is a programme that had a fresh start and a clean ending.
“Most importantly, GCP has enabled plant breeders to embrace cutting-edge science through partnerships that focused on improving crop yields in areas previously deemed unproductive,” he says. “GCP is unique, one-of-a-kind, and I love it!”
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.
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.
“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.”
Harvested groundnuts in Senegal.
How Africa lost its groundnut export market
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.”
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.
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.
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.
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.”
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.
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.
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
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.
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.”
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.
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.
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.
“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.
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.
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.
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.”
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.
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.”
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
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.
Malawian farmer Jinny Lemson grows beans to feed her livestock.
Ethiopia’s new bean breeders
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.”
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.”
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.
“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.”
Bean trials at KALRO in Kenya.
Kenya chasing higher bean yields
Across the border, Kenya has also been facing staffing issues.
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.”
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.”
Varieties fare differently in KALRO bean trials in Kenya.
Commercialising beans
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
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.”
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.
Barley is thought to have been one of the first crops ever cultivated by humankind. This is largely because it is a tough plant able to withstand dry and salty conditions. Its fortitude is especially important for the small land-holders living on the fringes of deserts in West Asia and North Africa, where it is “the last crop grown before the desert,” says Dr Michael Baum, who led barley research for the CGIAR Generation Challenge Programme (GCP).
“Looking at wild barley is especially important for low-input agriculture, such as is found in developing countries,” he says. “Wild barley grows in, and is very adapted to, the harsh conditions at the edge of the deserts in the Fertile Crescent of West Asia: Iraq, Syria, Jordan and Turkey.”
In some regions, wild barley produces an even higher yield of grain when there is a drought. And this was the kind of useful trait that GCP researchers were looking for in their work on barley during the first phase of GCP, when the internationally funded Programme set out to enhance genetic stocks and plant-breeding skills that will help developing nations cope with increasingly extreme drought conditions.
Barley a ‘chosen one’ for research
Preparing barley in Ethiopia.
During its first five years, GCP chose barley as one of its focus crops as advances had already been made in understanding its genetic makeup and in using new molecular plant-breeding technologies to find and incorporate useful genes into barley varieties.
“At the same time, we needed to find the genes or characteristics we did not want in cultivated barley so we could avoid these traits,” says Michael. “This includes the way wild barley disperses its seed when its brittle spikes shatter. Domesticated barley has non-shattering spikes, making it much easier to harvest.”
Resource-poor farmers mostly grow barley in poor environments, where yields of key crops are chronically low, and crop failures are common. Resilient, high-yielding varieties could make a big difference to livelihoods.
Farmers in Central and West Asia and North Africa (CWANA) plant more than five million hectares of barley each year, where it is largely used as feed for the sheep and goats that are the main source of meat, milk and milk products for rural populations. In these environments, barley grain is harvested only two to three times over a five-year period. In years when it is too dry, sheep are sent into the barley field to graze on the straw.
Barley-based livestock system on marginal drylands in Morocco.
Finding the clues to help breeders select barley’s best DNA
Malted barley.
The quest for better barley varieties – those that yield more, have more protein, can resist pests and diseases and can tolerate drought – means understanding what genes for what characteristics are available to plant breeders.
With 2,692 different barley accessions (or genetically different types of barley) in the ICARDA collection, from 84 different countries, this is no mean feat. GCP-supported researchers selected seed from 1,000 of the most promising accessions and planted single plants, whose seed was then ‘fingerprinted’, or genotyped, according to its DNA composition.
“From this, we selected 300 different barley lines that represented 90 percent of all the different characteristics of barley,” says Michael.
“This [reference set] is really good for someone new to barley. By looking at 300 lines they are seeing the diversity of almost 3,000 lines without any duplication,” he says. “This is much better and quicker for a plant breeder.”
The reference set of 300 barley lines is now available to plant breeders through the ICARDA gene bank.
Barley growing on experimental fields in Morocco.
Checking out the effects of the environment on gene expression
Harvesting barley in Nepal.
It’s not enough to discover what genes are present in different varieties of barley. It’s also important to understand how these genes express themselves in terms of barley’s yield, quality (especially protein content) and adaptation to stresses such as drought when grown in different environments.
To make this happen, GCP improved collaboration across research centres. This increased the probability of relatively quick advances in identifying new traits and opportunities to improve barley varieties for the poorer farmers of CWANA.
GCP funded a collaborative project between ICARDA and researchers in Australia (the University of Adelaide and the Australian Centre for Plant Functional Genomics), Italy (l’Università degli Studi di Udine) and Syria (Tishreen University) to apply a new method, analysing allele-specific expression (ASE), to understand how genes express themselves in barley, using experimental hybrid plants (cultivated plants crossed with wild barley plants). Over three years, the collaboration tested 30 genes and 10 gene-cross combinations and found that there were changes in genetic expression when plants were grown in drought conditions.
“This is a project we could not have done without the partners in the GCP collaboration,” says Michael. “We gained important insights into how genes are regulated and how gene expression changes under different environmental conditions, such as drought, or during growth stages, such as early plant development or grain filling. We published our results in a high-impact journal [The Plant Journal (2009) 59(1):14–26], which was a great outcome for a project with such a limited timespan.”
This project was designed not so much for the practical plant breeder, but for those using molecular-breeding technologies where it is important to understand that there is a change in the expression of genes over the lifetime of a plant. “This affects the selection of genes for breeding programmes,” says Michael.
Preparing barley in Ethiopia.
Making the most of wild barley
Wild barley in flower.
Once some of the fundamental research into barley’s building blocks had been done, GCP revisited the potential of wild barley, with the aim to identify specific DNA that increased or decreased drought tolerance.
“Whenever you can’t find the characteristics you are looking for in a cultivated crop, you go back to look again at the wild varieties,” says Michael.
Joanne Russell from the James Hutton Institute says success came when “we combined the power of genomics with a unique population of 140 barley lines to identify segments of the donor genome that confer drought tolerance”.
The barley lines were composed of an advanced elite genetic background combined with introduced segments of DNA from wild barley that came from the Fertile Crescent.
“We were successful in identifying parts of the DNA from hybrid plants that confer a significant increase in yield under drought,” says Joanne.
Leader of this GCP project from the James Hutton Institute, Professor Robbie Waugh, adds that GCP provided a unique opportunity for their laboratory to interact with international colleagues on a project focussed on improving the plight of some of the world’s poorest subsistence farmers.
“The genetic technologies we had developed prior to the GCP project starting were, at the time, state of the art – even in the more developed world,” says Robbie. “Our ability to then apply these technologies to wild barley genetic material from ICARDA and to varieties derived from wild × cultivated crosses allowed us to learn a lot about patterns of genetic and phenotypic variation in the wider barley gene pool.
“Indeed, we are still working on one of the genetic populations of barley that we studied in the GCP program, now using sophisticated phenotyping tools and approaches to explore how genes in defined segments of the wild barley genome help provide yield stability under drought conditions through architectural variation in the root system.”
Women harvesting barley in India.
GCP builds genetic resources through ongoing collaboration
Barley in rural Ethiopia.
For Michael, one of the most important outcomes of the GCP work was the ability to meet and work with researchers from other centres across the world.
“Before GCP, I had only visited two other CGIAR centres,” he says. “GCP was the first attempt to develop a programme across the CGIAR centres and to work on a specific topic, which was genetic resources. I would give GCP high marks for stimulating this cross-centre cooperation, particularly through their annual GCP meeting.”
And when the decision came to end barley research after the first phase of GCP, Michael found that he missed the GCP meetings: “I would have found it useful if I could have continued to attend the annual meetings,” he says. “These were much more important to me than getting the project funding out of GCP.”
Despite this and despite dealing with the challenge that some countries, such as China, were unable to provide the barley germplasm (samples of materials) that they initially promised, Michael has continued his relationships with some of the people he first met through GCP. “I’m still collaborating with China through a continuous bilateral effort on barley. Ten years later, the collaborations are still ongoing. Often when a project finishes, the collaboration finishes, but we are still continuing our collaboration on barley.”
Most importantly, Michael believes the GCP-supported and -funded collaborations brought a new approach to providing plant genetic resources to breeders. “The reference sets we assembled for barley and other crops provided a new way to look at large germplasm collections,” he says.
“This was one aim of GCP: about how to have a more rational look at germplasm collections. Now plant breeders don’t have to ask for five to ten thousand accessions of a crop, and then spend several years on evaluation.
“Now they have a higher chance of finding the genetic characteristics they want more quickly from the much smaller reference collection.”
And although the reference-set approach has been further refined since GCP’s first phase of research concluded, Michael believes it builds on what GCP started through its collaborative teams, with barley being just one example.
“GCP helped make it all happen,” he says.
For research and breeding products, see the GCP Product Catalogue and search for barley.
“With the Community of Practice you can call on other scientists; you share talk, you share ideas, you share joy. We share everything together,” Elizabeth enthuses. ‘Joy’ is a word that is often on Elizabeth’s lips when she describes the help that GCP has given her and others.
In less than a decade, Elizabeth has become a valued researcher at CRI (currently on secondment at the International Institute of Tropical Agriculture, IITA) as well as Ghana’s leading GCP-supported scientist working on cassava. But in fulfilling her own destiny, she’s also passionate about helping others to achieve their potential.
