Chris Ojiewo, from CIMMYT, emphasizes the urgent need for African farmers to produce more food within restricted areas to accommodate the continent’s growing population. He advocates for increasing crop productivity by developing resilient varieties and advanced production systems that can thrive in intensified and drought-prone conditions. Ojiewo suggests boosting maize yields from one ton per hectare to higher levels through innovative agricultural practices, highlighting CIMMYT’s role in addressing food security challenges exacerbated by climate change.
CIMMYT collaborates with Indian research institutions like IIWBR to develop climate-resilient wheat varieties, supplying essential genetic materials and leveraging global research initiatives, advanced breeding techniques, and technological tools. This partnership accelerates the creation and distribution of resilient crops, supporting local scientists and smallholder farmers through training, capacity-building programs, and knowledge sharing to ensure sustainable agriculture and enhanced food security in the face of climate change.
Children walk to their shelter at an IDP camp near El Fasher, the capital of North Darfur, Sudan. (Photo: Shehzad Noorani/UNICEF)
Sudan, the third largest country in Africa, is on the verge of a food crisis of epic proportions. Since the outbreak of civil war in April 2023, the country has descended rapidly into political upheaval, severe economic contraction, extreme social unrest, and rampant violence.
In addition to the estimated 13,000-15,000 people killed and 33,000 injured, some 6.3 million people have been internally displaced and more than 1.7 million have crossed into neighboring countries as refugees. Many are women and children.
The United Nations considers this the largest child displacement crisis in the world. About 25 million people urgently require food assistance, including more than 14 million children. Acute food insecurity is affecting 18 million people, or 37 percent of the population, with another 10 percent in emergency conditions.
News stories are dominated by reports of violent clashes and political maneuverings. So far, coverage of food insecurity has been scant. As is often the case, this topic seems to only get traction when there is outright famine.
This gets the story backwards. Food insecurity is at the root of many conflicts. Moreover, peace remains elusive without well-functioning agricultural systems, and it is unreasonable to expect viable agricultural production without peace.
Anticipating significantly reduced harvests in Sudan, UN agencies are projecting 50-100 percent price hikes for staple grains over the coming months. Following a doubling in food price over the previous two years, Sudan’s need for food aid will grow exponentially, while logistical barriers to humanitarian operations are getting harder to overcome.
The UN Office for the Coordination of Humanitarian Affairs (UNOCHA) has called for peace-building, unimpeded passage of humanitarian relief, and agricultural livelihood support. And the World Food Program warns that without substantial intervention, catastrophic hunger is likely to prevail in conflict hotspots by next year’s lean season.
Most of Sudan’s 45 million people rely on farming for their livelihoods. Yet only 3.5 percent of requested donor funding for the 2024 Sudan Humanitarian Needs and Response Plan has been provided.
With more frequent and severe droughts and floods degrading agricultural productivity, the income and food security of farming families has become more precarious over recent decades. Concurrent erosion in governance and social protection systems accelerates a vicious cycle of vulnerability, social tension, and maladaptive coping strategies.
In already fragile agricultural areas, displacement of millions of people is severely impacting the agriculture sector, disrupting input supply and agricultural services and limiting labor availability. Producers, input suppliers, processors, and traders all struggle to operate with communication systems interrupted by conflict preventing normal commercial transactions and movement of produce.
Just five years ago, Sudan’s agri-food sector contributed 32 percent to total GDP. In 2023, the country has seen a 20 percent drop in agricultural GDP and employment. If no preventive action is taken this year, an estimated 1.8 million more people will fall into poverty amid the ongoing conflict.
With significant untapped agroecological potential, Sudan’s economic and political stability depends on a transition to productive and climate-resilient agriculture. But this demands investment in farm management capacity, improved use of inputs and irrigation, and increased access to markets and finance, as well as viable governance of rural infrastructure and natural resources. The situation in Sudan is especially challenging given the weakened state of agricultural supply chains and the extension system, the two backbones of the agricultural sector.
To boost food supplies and prevent depletion of productive assets, international organizations are working to provide Sudanese farmers with high-quality seeds, agrochemicals, livestock vaccines, and fuel on an emergency basis. The situation requires the sustained presence of support agencies.
However, the blanket economic embargo placed on Sudan has made it difficult, if not impossible, for local development agencies to access project funds vital for saving lives and sustaining livelihoods.
Extreme uncertainty in conflict zones hampers interventions designed to reduce dependency on food aid and increase the resilience of local farming systems. By sharing knowledge resources, foresight capabilities, and decision frameworks, partner organizations can better anticipate and reduce human suffering and disaster relief costs.
Sudan is facing a complex emergency, which may lead to state failure, mass migration, resource conflicts, and starvation, triggering waves that would be felt across all of northeastern Africa. Sudan is too big to fail.
Climate-resilient agricultural livelihoods are the engine of food security and social stability. This cannot be achieved in one or two years, so the global community must have long-term aspirations to support the transformation of agrifood systems in Sudan.
We need to adapt our strategies to build resilience before, during, and after periods of conflict. By reducing poverty, in-country inequality, and other societal drivers, increased agricultural resilience can help mitigate and moderate conflict.
The victims of the current conflict have no political capital and may have little idea why the warring sides took up arms. To relieve the extreme suffering in Sudan, it is the responsibility of the international community to marshal the political will to achieve a negotiated truce and a sustained ceasefire.
The authors are thought leaders of CGIAR, the world’s largest global agricultural innovation network, and lead respectively CIMMYT, CGIAR, WorldVeg Africa, The Alliance CIAT Bioversity, IFPRI, CIP and ICARDA.
The West Africa Regional Consultation Conference, organized by CIMMYT and the African Drylands Crop Improvement Network in Accra, addressed pressing issues in the region’s agricultural sector, notably in dryland farming amid climate change. CIMMYT’s Dr. Paswel Marenya emphasized the need to boost yields of crucial cereals like sorghum and millet through innovative practices discussed at the conference. With 47 scientists from nine countries participating, the event aimed to foster collaboration and drive tangible improvements in food security and livelihoods across West Africa.
Map: BISA works with National Agricultural Research Systems (NARS) of South Asia to develop ACASA.
Atlas of Climate Adaptation in South Asian Agriculture (ACASA) is different from many projects supported by our team. I would love to dive into the promising features of the ACASA platform and the exciting technical advances being made, but I want to focus here on how the Borlaug Institute for South Asia (BISA) has organized this program for greater and longer-term impact.
BISA is a strong regional partner and is the lead institution for the ACASA program. In fact, we could have simply asked BISA to build the ACASA platform and known they would make a great technical product. However, our goal is not just to have great technical products, but also to improve the lives of small-scale producers. For any great technical product to deliver impact, it must be used.
From day one, the ACASA program has not just kept the users’ needs in mind, indeed they have kept the users themselves engaged on the project. By establishing strong, financially supported partnerships with the National Agricultural Research Systems (NARS) in Bangladesh, India, Nepal, and Sri Lanka, they are achieving four key outcomes, among many others:
Benefit from local expertise regarding national agricultural practices, climate risks, and solutions
Leverage NARS connections to national and subnational decision makers to inform product requirements
Establish national ownership with a partner mandated to support users of the product
Strengthen climate adaptation analytics across South Asia through peer-to-peer learning.
These outcomes lead to more accurate and appropriate products, user trust, and the long-term capacity to maintain and update the ACASA platform. The latter being essential given the constantly improving nature of our understanding of and predictions around climate and agriculture.
If this model of working has such advantages over âif you build it, they will comeâ, you might wonder why we do not use it in all cases. This approach requires divergence from business-as-usual for most researchers and is not without a cost. The BISA team are not only putting deep emphasis on the technical development of this product, but they are also spending considerable time, effort, and budget to create a program structure where the NARS are catalytic partners. The NARS teams are empowered on the project to contribute to methodologies used beyond their national boundaries, they have the task of making the best data available and validating the outputs, the responsibility of understanding and representing stakeholder requirements, and the ownership of their national platform for long-term use. BISA has developed a structure of accountability, provided funding, facilitated team-wide and theme-specific workshops, and shared decision-making power, which all presents additional work.
In the end, we encouraged this approach because we see too many decision support tools and platforms developed by international researchers who merely consult with users a few times during a project. These efforts may result in building captivating products, meeting all the needs brainstormed by the research team, but their future is sitting in a dusty (and unfortunately crowded) corner of the internet. While this approach seems fast and efficient, the efficiency is zero if there is no value gained from the output. So, we look for other ways to operate and engage with partners, to work within existing systems, and to move beyond theoretically useful products to ones that are used to address needs and can be evolved as those needs change. BISA has been an exemplary partner in building and supporting a strong ACASA team, and we are eager to see how each NARS partner leverages the ACASA product to generate impact for small-scale producers.
Tess Russo is a senior program officer at the Bill & Melinda Gates Foundation, based in Seattle, United States. Â
Researchers, funded by the GRDC, are collaborating with experts from ANU, the University of Adelaide, and CIMMYT to enhance heat tolerance in wheat. Led by Professor Owen Atkin and Dr. Scott Boden, the projects aim to identify genetic markers for breeding heat-resistant varieties. Using advanced phenotyping technology, scientists are exploring biochemical pathways and heat shock proteins to develop solutions for climate change-induced challenges in agriculture.
CIMMYT is combating the effects of El Niño and climate change by fostering climate-smart agriculture, including drought-tolerant crops and conservation practices, to bolster smallholder farmer resilience and productivity. Through partnerships and sustainable farming innovations, CIMMYT aims to improve food security and adapt to environmental challenges, ensuring that advanced technologies benefit those most in need.
From the densely lush landscape of Zambiaâs northern province to the arid terrain of the south, a stark reality unfolds, intensified by El Niño. Zambia’s agriculture faces contrasting realities yet potential lies in adaptive strategies, a diversified crop basket, and collaborative initiatives which prioritize farmers. Despite persistent challenges with climate variability and uneven resource distribution, the country navigates unpredictable weather patterns, emphasizing the intricate interplay between environmental factors and adaptation strategies.
A healthy maize and groundnut stand in the northern Province (left) and a wilting maize crop in the southern Province (right). These photos were taken two days apart. (Photo: Blessing Mhlanga/CIMMYT)
Unpacking El Niño’s impact in Zambia
El Niño presents a common challenge to both southern and northern Zambia, albeit with varying degrees of intensity and duration. The 2022/2023 season had above normal rainfall amounts, with extreme weather events, from episodes of flash floods and flooding to prolonged dry spells, especially over areas in the south. In the 2023/2024 season, the southern region has already experienced irregular weather patterns, including prolonged droughts and extreme temperatures, leading to water scarcity, crop failures, and significant agricultural losses. Although the growing season is nearing its end, the region has only received less than one-third of the annual average rainfall (just about 250 mm). Dry spells of more than 30 days have been experienced and, in most cases, coincide with the critical growth stages of flowering and grain-filling. A glance at farmersâ fields paints a gloomy picture of the anticipated yield, but all hope is not lost.
In contrast, the northern province stands out receiving above-average rainfalls beyond 2,000 mm, providing a different set of challenges for crop production. In this region, incidences of waterlogging are prominent although the effects are not as detrimental as the drought in the southern province. In general, crops in the northern province promise a considerable harvest as compared to the ones in the southern province.
Maize stover and its competing use
The scarcity of resources in southern Zambia extends beyond water availability, with the competition for maize stover, a valuable byproduct used for animal feed which can also be retained on the soil surface for fertility improvement and soil moisture conservation. With limited access to alternative fodder sources, farmers face challenges in meeting the nutritional needs of their livestock while maintaining soil fertility and conserving moisture. The struggle to balance the competing demands for maize stover underscores the complex dynamics of resource management in the region. This is further worsened by the low maize stover yield expected due to the dry conditions.
Implementing fodder trials, which include cultivating fodder crops like mucuna and lablab, intercropped or rotated with maize, offers a lifeline to farmers. While maize crops may wilt under the stress of El Niño-induced droughts, leguminous crops such as mucuna, lablab, cowpea, and groundnuts exhibit resilience, thriving in adverse conditions and providing a crucial source of food, feed, soil cover, and income for farmers. The ability of legumes to withstand environmental stressors highlights the importance of crop diversification in building resilience to climate change and ensuring food security in vulnerable regions.
Conversely, in northern Zambia, the abundance of agricultural resources allows for a more sustainable utilization of maize stover. Farmers have greater access to fodder alternatives and can implement integrated farming practices to optimize the use of crop residues. This enables them to mitigate the adverse effects of soil degradation and enhance livestock productivity, contributing to the resilience of their agricultural systems.
Use of more climate-smart crops
Drought-tolerant cassava grown in the northern province. (Photo: CIMMYT)
In southern Zambia, maize stands as the main crop, often supplemented with the integration of some leguminous crops integrated to some extent, to diversify the agricultural landscape. However, the relentless and longevity grip of El Niño has taken a negative toll on maize production, despite efforts to cultivate drought-tolerant varieties. As the dry spell persists, maize plants at the critical tasseling and silking stage face an uphill battle, as the dry and hot air has adversely impacted pollen and silk development.
The dissimilarity with the northern province, where cassava thrives from abundant water, is striking. This resilient crop, known for its drought tolerance, presents a promising alternative for farmers in the southern province grappling with erratic rainfall patterns. As climate change continues to challenge traditional agricultural practices, exploring resilient crops like cassava may offer a lifeline for communities striving to adapt and thrive amidst adversity.
The SIFAZ project is designed around the idea that strip crops and intercrops can add nutritional and economic value to Conservation Agriculture (CA) systems for smallholder farmers in Zambia. While traditional yield metrics provide some insight across the several intercropping treatments being tested on-farm, the true benefits of these cropping systems extend beyond mere output. SIFAZ recognizes the diversification synergy, emphasizing that “two crops are better than one.”
However, the outcomes of the SIFAZ project and the CGIAR Initiative on Diversification in East and Southern Africa have varied over the years between the two regions, reflecting the discrepancy in their agricultural landscapes.
Notably, regional differences in the adoption and success of these cropping systems have become apparent. In the northern province, crop-centric approaches prevail, leading to a higher concentration of successful crop farmers. Meanwhile, in the southern province, mixed systems that incorporate mixed crop-livestock systems achieve desirable effects. These findings highlight the importance of tailoring agricultural interventions to suit the specific needs and conditions of diverse farming communities.
Navigating the complex challenges of climate change requires a multifaceted approach that acknowledges the unique realities of different regions. By embracing adaptive strategies, harnessing indigenous knowledge, and fostering collaborative partnerships, Zambia can forge a path towards a more resilient and sustainable agricultural future, where farmers thrive despite the uncertainties of a changing climate.
Agrovegetal delegation stands with CIMMYT leaders and researchers. (Photo: CIMMYT)
A new agreement between a leading Spanish seed company, Agrovegetal, and the international research center CIMMYT will help safeguard the regional availability of high-yielding, climate-resilient varieties of wheat, the regionâs vital food staple.
The agreement was signed on 21 February 2024 at the Mexico headquarters of CIMMYT, a non-profit organization whose breeding contributions are present in half the maize and wheat varieties sown in low- and middle-income countries.
It comes at a time when severe drought threatens wheat crops in Southern Europe and North African nations such as Algeria, Morocco, and Tunisia and imports of wheat grain from traditional suppliers âRussia, the EU, Ukraine, and the USâare costly and constrained.
Since its formation in 1998 as a conglomerate of seed-producing cooperatives and a few industrial partners, Agrovegetal has been testing hundreds of CIMMYT breeding lines of bread and durum wheat (the latter used for pasta and couscous) and triticale (a wheat x rye hybrid) and returning high-quality data each year on the performance of this germplasm.
âThe erratic rainfall, droughts, and crop disease patterns of AndalucĂa in southern Spain, where Agrovegetal tests the lines, are very much like those of North Africa, an important target region for CIMMYT genetics and agronomic solutionsâ said Bram Govaerts, director general of CIMMYT. âThis new agreement, which guarantees the Agrovegetal-CIMMYT partnership through 2028, thus helps ensure CIMMYTâs capacity to offer outstanding, well adapted lines for the Mediterranean region, including North Africaâs national breeding programs, a great boon to farmers and consumersâ economies, food security, and nutrition.â
For its part, after several years of testing, Agrovegetal registers the most promising CIMMYT lines as improved varieties in Spain and markets their seed to members of its cooperatives.
âFor us, the contributions of CIMMYT are invaluable,â said Ignacio Solis Martell, the companyâs technical director. âThanks to CIMMYT’s exceptional genetic material, Agrovegetal has become synonymous with resilience in Andalusia. Our varieties are renowned for their performance in the face of adversity, whether it be disease, drought, or other challenges.â
According to Govaerts, Agrovegetal offers an excellent model for burgeoning private seed enterprises in North Africa and elsewhere. âIt shows how farmers, seed producers, and industry can join forces, skills, and resources to control seed, a critical factor in food production.â
CIMMYT’s latest study reveals climate change could significantly expand wheat blast’s reach by 2050, threatening a 13% drop in global wheat production. The research highlights the critical need for developing resistant wheat varieties and adapting farming practices to counter this growing threat to food security.
CIMMYT has introduced 20 heat-resistant maize hybrids in South Asia, including Pakistan, to boost resilience against climate change and support smallholder farmers. This breakthrough, achieved after a decade of collaboration with regional research institutes and seed companies, aims to secure food supplies amid rising temperatures. Through initiatives like Pakistan’s Agricultural Innovation Programme, CIMMYT is committed to enhancing maize production and food security, showcasing the power of scientific innovation in addressing global agricultural challenges.
The 2023 UN Climate Change Conference (COP 28) took place from November 30 to December 12, 2023, in Dubai, UAE. The conference arrived at a critical moment when over 600 million people face chronic hunger, and global temperatures continue to rise at alarming rates. CIMMYT researchers advocated for action into agricultureâs mitigating role in climate change, increasing crop diversity, and bringing the tenets of sustainability and regenerative agroecological production systems to a greater number of farmers.
Directly addressing the needs of farmers, CIMMYT proposed the creation of an advanced data management system, training, and protocols for spreading extension innovations such as digital approaches and agronomic recommendations to farmers via handheld devices to harmonize the scaling in Africa of regenerative agricultureâdiverse practices whose outcomes include better productivity and environmental quality, economic feasibility, social inclusivity, and nutritional security.
CIMMYT presented research showing that in times of fertilizer shortages, targeting nitrogen supplies from inorganic and organic sources to farms with minimal access to nitrogen inputs can improve nitrogen-use efficiency and helps maintain crop yields while limiting harm from excesses in fertilizer use. Examining how food production is driving climate change, CIMMYT promoted ways to lessen climate shocks, especially for smallholder farmers who inordinately suffer the effects of climate change, including rising temperatures and extended droughts. Improved, climate-resilient crop varieties constitute a key adaptation. Boosting farmer productivity and profits is a vital part of improving rural livelihoods in Africa, Asia, and Latin America.
When asked about CIMMYTâs contribution to COP 28, Bram Govaerts, CIMMYTâs director general, highlighted the inclusion of agriculture in the COP28 UAE Declaration on Sustainable Agriculture, Resilient Food Systems, and Climate Action as part of various potential solutions for climate change, an effort that CIMMYT supported through advocacy with leaders and government officials.
âOur participation addressed some of the pressure points which led to this significant recognition. It further cleared our role as an active contributor to discussions surrounding the future of food and crop science,â said Govaerts.
Sarah Hearne presents on the potential of crop diversity to help combat climate change impacts on agrifood systems. (Photo: Food Pavilion/COP 28)
Hearne explained the process that characterizes plant DNA to identify the ideal, climate-adaptable breeding traits. This classification system also opens the door for genetic modeling, which can predict key traits for tomorrowâs climatic and environmental conditions.
âOur thinking must shift from thinking of gene banks to banks of genes, to make vibrant genetic collections for humanity, opening up genetic insurance for farmers,â said Hearne.
Working towards a food system that works for the environment
With an increased strain on food production, sustainability becomes critical for long-term human and environmental health. Sarah Hearne and Tek Sapkota, agricultural systems and climate change senior scientist, from CIMMYT participated in a panel discussion: Responsible consumption and sustainable production: pathways for climate-friendly food systems. They shared how progress in genetic innovation and fertilizer use can contribute to sustainable consumption and a resilient food system.
Fertilizer use remains highly skewed, with some regions applying more fertilizer than required and others, like sub-Saharan Africa, not having sufficient access, resulting in low crop yields. However, to achieve greater food security, the Global South must produce more food. For that, they need to use more fertilizer. Just because increased fertilizer use will increase greenhouse gases (GHGs) emissions, institutions cannot ask smallholder farmers not to increase fertilizer application. Increased GHGs emission with additional fertilizer application in low-input areas can be counterbalanced by improving Nutrient-Use Efficiency (NUE) in high-output areas thereby decreasing GHGs emissions. This way, we can increase global food production by 30% ca with the current level of fertilizer consumption.
Tek Sapkota speaks on how sustainable and efficient fertilizer use can contribute to a resilient food system. (Photo: Food Pavilion/COP 28)
“This issue needs to be considered through a holistic lens. We need to scale-up already proven technologies using digital extensions and living labs and linking farmers with markets,â said Sapkota.
On breeding climate-resilient seeds, Hearne addressed whether farmers are accepting new seeds and how to ensure their maximum adoption. Hearne detailed the partnership with CGIAR and NARS and the numerous technologies advancing the selection of ideal breeding traits, considering shortened breeding cycles, and responding to local needs such as heat or flood tolerance, and traditional preferences.
âDrought-tolerant maize, developed by CIMMYT and the International Institute of Tropical Agriculture (IITA), has benefited over 8 million households in sub-Saharan Africa, which proves that farmers are increasingly receptive to improved seeds. With a better selection of appropriate traits, we can further develop and distribute without yield penalties,â said Hearne.
Regenerative and agroecological production systems
Researchers have studied regenerative and agroecological production systems for decades, with new and old research informing current debates. These systems restore and maintain ecosystems, improving resource use efficiency, strengthening resilience, and increasing self-sufficiency. In his keynote presentation, Sapkota presented 3 examples of regenerative agriculture and agroecological systems: Â conservation agriculture, cropping system diversification and site-specific nutrient management and their impact on food production, climate change adaptation and mitigation.
âAs the science continues to develop, we need to harness digital capacity to co-create sustainable solutions alongside local, indigenous knowledge,â said Sapkota. âWhile we should continue research and innovation on cutting-edge science and technologies, we should also invest in knowledge sharing networks to spread access to this research; communication is fundamental for further adoption of these practices.â
In Busia, Chris Ojiewo from CIMMYT and partners are spearheading the adoption of high-yielding millet varieties to boost food security and tackle climate change. This initiative aims to equip farmers with quality seeds and modern farming techniques, ensuring the sustainable cultivation of millet, a crop resilient to harsh climates.
After a decade of rigorous effort, CIMMYT, along with public-sector maize research institutes and private-sector seed companies in South Asia, have successfully developed and released 20 high-yielding heat-tolerant (HT) maize hybrids across Bangladesh, Bhutan, India, Nepal, and Pakistan. CIMMYT researchers used a combination of unique breeding tools and methods including genomics-assisted breeding, doubled haploidy (a speed-breeding approach where genotype is developed by chromosome doubling), field-based precision phenotyping, and trait-based selection to develop new maize germplasm that are high-yielding and also tolerant to heat and drought stresses.
While the first batch of five HT maize hybrids were released in 2017, by 2022 another 20 elite HT hybrids were released and eight varieties are deployed over 50,000 ha in the above countries.
In South Asia, maize is mainly grown as a rainfed crop and provides livelihoods for millions of smallholder farmers. Climate change-induced variability in weather conditions is one of the major reasons for year-to-year variation in global crop yields, including maize in Asia. It places at risk the food security and livelihood of farm families living in the stress-vulnerable lowland tropics. âSouth Asia is highly vulnerable to the detrimental effects of climate change, with its high population density, poverty, and low capacity to adapt. The region has been identified as one of the hotspots for climate change fueled by extreme events such as heat waves and intermittent droughts,â said Pervez H. Zaidi, principal scientist at CIMMYT.
Heat stress impairs the vegetative and reproductive growth of maize, starting from germination to grain filling. Heat stress alone, or in combination with drought, is projected to become a major production constraint for maize in the future. âIf current trends persist until 2050, major food yields and food production capacity of South Asia will decrease significantlyâby 17 percent for maizeâdue to climate change-induced heat and water stress,â explained Zaidi.
From breeding to improved seed deliveryâthe CIMMYT intervention
In the past, breeding for heat stress tolerance in maize was not accorded as high a priority in tropical maize breeding programs as other abiotic stresses such as drought, waterlogging, and low nitrogen in soil. However, in the last 12â15 years, heat stress tolerance has emerged as one of the key traits for CIMMYTâs maize breeding program, especially in the South Asian tropics. The two major factors behind this are increased frequency of weather extremes, including heat waves with prolonged dry period, and increasing demand for growing maize grain year-round.
At CIMMYT, systematic breeding for HT maize was initiated under Heat Stress Tolerant Maize for Asia (HTMA), a project funded by the United States Agency for International Development (USAID) Feed the Future program. The project was launched in 2013 in a publicâprivate alliance mode, in collaboration with public-sector maize research institutions and private seed companies in Bangladesh, Bhutan, India, Nepal, and Pakistan.
The project leveraged the germplasm base and technical expertise of CIMMYT in breeding for abiotic stress tolerance, coupled with the research capacity and expertise of the partners. An array of activities was undertaken, including genetic dissection of traits associated with heat stress tolerance, development of new HT maize germplasm and experimental hybrids, evaluation of the improved hybrids across target populations of environments using a heat stress phenotyping network in South Asia, selection of elite maize hybrids for deployment, and finally scaling via publicâprivate partnerships.
Delivery of HT maize hybrids to smallholder farmers in South Asia
After extensive testing and simultaneous assessment of hybrid seed production and other traits for commercial viability, the selected hybrids were officially released or registered for commercialization. Impact assessment of HT maize hybrid seed was conducted in targeted areas in India and Nepal. Studies showed farmers who adopted the HT varieties experienced significant gains under less-favorable weather conditions compared to farmers who did not.
Under favorable conditions the yield was on par with those of other hybrids. It was also demonstrated that HT hybrids provide guaranteed minimum yield (approx. 1 t ha-1) under hot, dry unfavorable weather conditions. Adoption of new HT hybrids was comparatively high (19.5%) in women-headed households mainly because of the âstay-greenâ trait that provides green fodder in addition to grain yield, as women in these areas are largely responsible for arranging fodder for their livestock.
âSmallholder farmers who grow maize in stress vulnerable ecologies in the Tarai region of Nepal and Karnataka state in southern India expressed willingness to pay a premium price for HT hybrid seed compared to seed of other available hybrids in their areas,â said Atul Kulkarni, socioeconomist at CIMMYT in India.
Going forwardâpositioning and promoting the new hybrids are critical
A simulation study suggested that the use of HT varieties could reduce yield loss (relative to current maize varieties) by up to 36% and 93% by 2030 and by 33% and 86% by 2050 under irrigated and rainfed conditions respectively. CIMMYTâs work in South Asia demonstrates that combining high yields and heat-stress tolerance is difficult, but not impossible, if one adopts a systematic and targeted breeding strategy.
The present registration system in many countries does not adequately recognize the relevance of climate-resilience traits and the yield stability of new hybrids. With year-to-year variation in maize productivity due to weather extremes, yield stability is emerging as an important trait. It should become an integral parameter of the registration and release system.
Positioning and promoting new HT maize hybrids in climate-vulnerable agroecologies requires stronger publicâprivate partnerships for increasing awareness, access, and affordability of HT maize seed to smallholder farmers. It is important to educate farming communities in climate-vulnerable regions that compared to normal hybrids the stress-resilient hybrids are superior under unfavorable conditions and at par with or even superior to the best commercial hybrids under favorable conditions.
For farmers to be able to easily access the new promising hybrids, intensive efforts are needed to develop and strengthen local seed production and value chains involving small-and medium-sized enterprises, farmersâ cooperatives, and public-sector seed enterprises. These combined efforts will lead to wider dissemination of climate-resilient crop varieties to smallholder farmers and ensure global food security.
Climate change poses a threat to yields and food security worldwide, with plant diseases as one of the main risks. An international team of researchers, surrounding professor Senthold Asseng from the Technical University of Munich (TUM), has now shown that further spread of the fungal disease wheat blast could reduce global wheat production by 13% until 2050. The result is dramatic for global food security.
With a global cultivation area of 222 million hectares and a harvest volume of 779 million tons, wheat is an essential food crop. Like all plant species, it is also struggling with diseases that are spreading more rapidly compared to a few years ago because of climate change. One of these is wheat blast. In warm and humid regions, the fungus magnaporthe oryzae has become a serious threat to wheat production since it was first observed in 1985. It initially spread from Brazil to neighboring countries. The first cases outside of South America occurred in Bangladesh in 2016 and in Zambia in 2018. Researchers from Germany, Mexico, Bangladesh, the United States, and Brazil have now modeled for the first time how wheat blast will spread in the future.
Wheat fields affected by wheat blast fungal disease in Passo Fundo, Rio Grande do Sul, Brazil. (Photo: Paulo Ernani Peres Ferreira)
Regionally up to 75% of total wheat acreage affected
According to the researchers, South America, southern Africa, and Asia will be the regions most affected by the future spread of the disease. Up to 75% of the area under wheat cultivation in Africa and South America could be at risk in the future. According to the predictions, wheat blast will also continue to spread in countries that were previously only slightly impacted, including Argentina, Zambia, and Bangladesh. The fungus is also penetrating countries that were previously untouched. These include Uruguay, Central America, the southeastern US, East Africa, India, and eastern Australia. According to the model, the risk is low in Europe and East Asiaâwith the exception of Italy, southern France, Spain, and the warm and humid regions of southeast China. Conversely, where climate change leads to drier conditions with more frequent periods of heat above 35 °C, the risk of wheat blast may also decrease. However, in these cases, heat stress decreases the yield potential.
Wheat fields affected by wheat blast fungal disease in Passo Fundo, Rio Grande do Sul, Brazil. (Photo: Paulo Ernani Peres Ferreira)
Dramatic yield losses call for adapted management
The affected regions are among the areas most severely impacted by the direct consequences of climate change. Food insecurity is already a significant challenge in these areas and the demand for wheat continues to rise, especially in urban areas. In many regions, farmers will have to switch to more robust crops to avoid crop failures and financial losses. In the midwest of Brazil, for example, wheat is increasingly being replaced by maize. Another important strategy against future yield losses is breeding resistant wheat varieties. CIMMYT in collaboration with NARs partners have released several wheat blast-resistant varieties which have been helpful in mitigating the effect of wheat blast. With the right sowing date, wheat blast-promoting conditions can be avoided during the ear emergence phase. Combined with other measures, this has proven to be successful. In more specific terms, this means avoiding early sowing in central Brazil and late sowing in Bangladesh.
First study on yield losses due to wheat blast
Previous studies on yield changes due to climate change mainly considered the direct effects of climate change such as rising temperatures, changing precipitation patterns, and increased CO2 emissions in the atmosphere. Studies on fungal diseases have so far ignored wheat blast. For their study, the researchers focused on the influence of wheat blast on production by combining a simulation model for wheat growth and yield with a newly developed wheat blast model. Environmental conditions such as the weather are thus included in the calculations, as is data on plant growth. In this way, the scientists are modeling the disease pressure in the particularly sensitive phase when the ear matures. The study focused on the influence of wheat blast on production. Other consequences of climate change could further reduce yields.
Delivery of HT maize hybrids to smallholder farmers in South Asia 
