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Tag: climate smart maize breeding

Seeds to beat the heat in lowland tropics

South Asia, a region heavily impacted by climate change, faces rising temperatures, erratic monsoon rains causing intermittent drought and excessive moisture within the season, and frequent episodes of heat waves. These extreme weather events are challenging agrarian practices and affecting millions, especially smallholder farmers dependent upon rainfed cultivations. The halcyon days of consistent environmental conditions are gone, and adaptation and mitigation strategies have become essential in South Asia.

In May 2024, over 20 districts in the Terai region of Nepal and many parts of northern India recorded maximum temperatures between 40°C and 45°C, with several districts also experiencing heat waves during the same period. The temperature rise is not limited to the lowland plains; the effects are also being felt in the mountains, where rapid snowmelt is becoming increasingly common. In the Hindu Kush Himalayas region of Pakistan, farmers have had to shift their cropping cycles by a month to cope with drought stress caused by rising temperatures, which are leading to the early melting of snow in the region.

Partners in South Asia visiting heat stress tolerant hybrids demonstration in Nepal (Photo: CIMMYT-Nepal)

Collaborating to rise above the challenge

Amid the growing climate crisis, the Heat Stress Tolerant Maize for Asia (HTMA) project was launched by CIMMYT in 2012, with support from the United States Agency for International Development (USAID) under the Feed the Future initiative of the U.S. Government. The overarching goal of the HTMA project was to help farm families, particularly maize growers, to adapt to the impacts of soaring heat on maize productivity in South Asia. The project was implemented in partnership with 28 public and private sector stakeholders across the region and beyond to develop a multipronged approach to overcoming these challenges.

“Our aim is to develop and deploy maize hybrids with high yield potential and possess traits resilient to heat and drought stresses,” said P.H. Zaidi, Principal Scientist, and HTMA project lead at CIMMYT. Zaidi noted that during heat stress “high temperatures alone are not the only limiting factor- it is the combination of high temperature with low atmospheric humidity (high vapor pressure deficit), that creates a “killer combination” for maize production in the Asian tropics.”

This was also emphasized in a recently published article that he co-authored.

The development of heat stress-tolerant maize involves the use of cutting-edge breeding tools and methods, including genomics-assisted breeding, double haploidy, field-based precision phenotyping, and trait-based selection. Over 20 such hybrids have been officially released in India, Nepal, Bangladesh, Pakistan, and Bhutan. Between 2023 and 2024, over 2,500 metric tons of seed from these hybrids were distributed to farmers, helping them beat the heat.

Agile partnerships-from discovery to scaling

The first phase of the project (2012-2017) focused on discovering heat-tolerant maize varieties. During this time, pipeline products underwent field evaluations in stress-prone environments, leveraging the project’s product evaluation network of public and private partners, who contributed by managing trials and generating performance data. In the second phase (2018-2023), the focus shifted toward the deployment and scaling of heat-tolerant hybrids and strengthening seed systems in target countries to enable large-scale delivery, benefiting millions of farm families, particularly in South Asia’s rainfed ecologies. For example, the seed produced in 2023-2024 sufficed to cover over 125,000 hectares and benefited nearly 2.5 million people in the region.

HTMA project partners gathered in Nepal for the annual and project closure meeting (Photo-CIMMYT-Nepal)

Hailu Tefera, from USAID, praised the project’s success during the annual review and project closure meeting held in Nepal from August 21-22, 2024. We have seen great strides in scaling heat stress tolerant hybrids in the region. This initiative aligns with the US Government’s Global Food Security Strategy, where building farmers’ resilience to shocks and climate vulnerability is central,said Tefera, acknowledging the adaptive and agile partnership demonstrated by the project’s partners throughout HTMA’s discovery and scaling phases.

One of the project’s key achievements was creating a multi-stakeholder platform and leveraging resources across the region. Partners, including national agricultural research systems, seed companies, and higher learning institutes, expanded the project’s impact. The collaboration we fostered under the HTMA project is a working example of effective partnerships,” said B.M. Prasanna, Director of CIMMYT’s Global Maize Program. He highlighted how synergies with other developmental projects in the region, especially projects supported by the USAID country mission in Nepal helped launch local hybrid seed production, transforming the country from a net importer of hybrid maize seeds to producing locally in just a few years, and such seeds of resilience cover nearly 10,000 hectares in 2023/24 alone. Using heat tolerant (HT) maize seed allows smallholder farmers to harvest nearly one metric ton per hectare additional yield than normal maize under stress conditions.

The value of the seed these new hybrids was validated by adopter farmers who grow maize in stress-vulnerable ecologies by expressing their willingness to pay a premium price for HT hybrid seed as per the study conducted in Nepal and India. “The spillover effect of the project is helping countries like Bhutan to strengthen their seed systems and initiate hybrid seed production for the first time,” added Prasanna, expressing gratitude to USAID and all project partners.

The salient achievements of the project, including technical know-how, outputs, outcomes, and learnings were compiled as an infographic, titled “HTML Tool‘ and it was formally released by Narahari Prasad Ghimire, Director General of the Department of Agriculture, Government of Nepal, during the HTMA meeting in Nepal.

Rewarding achievement

Subash Raj Upadhyay, Managing Director of Lumbini Seed Company in Nepal, recalls the early days of producing heat stress-tolerant hybrid maize seed in Nepal, which began in 2018. “Our journey started with just one hectare of seed production in 2018 and 2019, and we expanded to 30 hectares by 2022. This was the first time that we started hybrid maize seed production in Nepal, specifically RH-10, a heat stress tolerant hybrid from CIMMYT, released by the National Maize Research Program of Nepal. The support of USAID’s projects like the Nepal seed and fertilizer project was crucial for our success,” said Upadhyay, who was among the award recipients for setting a potent example in scaling up heat stress-tolerant hybrids.

HTMA TOOL- an infographic launched during the meeting (Photo-CIMMYT Nepal)

In addition to Lumbini Seed Company, Jullundur Seed Private Limited Company in Pakistan was also recognized for its efforts in seed scaling. The National Maize Research Program of Nepal and the University of Agricultural Sciences, Raichur, India, were acknowledged for their rewarding achievement in research and development during the project period.

“The recognition exemplifies the public-private partnership that we demonstrated under the HTMA project, where the public sector mainly focused on strategic research and product development, and seed companies took charge of seed delivery and scaling,” said Zaidi during the project’s phaseout meeting in Nepal, attended by over 60 participants from the project’s target and spillover countries. “Such partnership models need to be strengthened and replicated in other projects. It is important to consolidate the gains and maintain the momentum of the HTMA project in the years to come to benefit millions of smallholder farmers, echoed Prasanna, who presented certificates of recognition to the partners in the presence of USAID representatives, senior government officials from Nepal and project partners from South Asia and beyond.

Heat tolerant maize hybrids: a pursuit to strengthen food security in South Asia

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. “South 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,” 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. “If current trends persist until 2050, major food yields and food production capacity of South Asia will decrease significantly—by 17 percent for maize—due to climate change-induced heat and water stress,” explained Zaidi.

From breeding to improved seed delivery–the 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 12–15 years, heat stress tolerance has emerged as one of the key traits for CIMMYT’s 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 public–private 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 public–private 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 “stay-green” trait that provides green fodder in addition to grain yield, as women in these areas are largely responsible for arranging fodder for their livestock.

“Smallholder 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,” said Atul Kulkarni, socioeconomist at CIMMYT in India.

Going forward–positioning 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. CIMMYT’s 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 public–private 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, farmers’ 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.

Market segmentation and Target Product Profiles (TPPs): developing and delivering impactful products for farming communities

Experimental maize field. (Photo: CIMMYT)

With the ever-changing climate conditions, including the unpredictable El Niño, and dynamic changes in government policies, understanding farmers’ preferences and market segmentation has become crucial for implementing impactful breeding programs. Market segmentation is a strategic process which divides a market into distinct group of consumers with similar needs, preferences, and behaviors. This allows organizations to tailor their products and services to specific customer segments, thus ensuring maximum value and impact.

In today’s fast-paced and evolving agricultural landscape, market segmentation plays a vital role in helping organizations navigate the complexities of a dynamic market. CIMMYT’s maize breeding program has a successful track record in developing and delivering improved varieties that are climate-resilient, high-yielding and suited to the rainfed tropical conditions in Africa. To further strengthen the impact, it is important to have a clear understanding of the evolving needs of farmers in different agroecological regions and the emerging market scenario so that breeding processes can be tailored based on market needs and client requirements.

Questions arise on how to refine the breeding programs relative to country-specific market segments, what efforts are underway to target these markets, and how do these markets transition. Recognizing the importance of market segmentation in refining breeding programs at the country and regional levels, CIMMYT hosted two workshops on maize market intelligence in Kenya and Zimbabwe, under the CGIAR Market Intelligence Initiative for eastern and southern Africa.

“Market intelligence in breeding programs is critical to understand the evolving needs of key stakeholders, including farmers, consumers, and the seed industry. It helps continuously improve the breeding pipelines to develop and deliver impactful products in targeted market segments. The workshops brought together relevant experts from the national programs and seed companies for focused discussions to develop a harmonized breeding strategy. This would help to address the needs of smallholder maize farmers in eastern and southern Africa,” said Director of CIMMYT’s Global Maize program and One CGIAR Global Maize Breeding Lead, B.M. Prasanna.

B.M. Prasanna delivers a presentation. (Photo: CIMMYT)

The workshops constituted a strategic continuation of the Product Design Team (PDT) meetings under CGIAR Market Intelligence, with a focus on the refinement of gender-intentional target product profile design. Guided by the expertise of CIMMYT’s Global Maize program, Market Intelligence, and ABI-Maize Transform teams, the sessions saw active participation from key stakeholders including lead breeders, seed systems experts, and market specialists from the National Agricultural Research and Extension Systems (NARES), alongside collaborative engagement with seed company partners. The workshops underscored the commitment to incorporate diverse perspectives, aligning with the evolving maize market landscape in eastern and southern Africa.

“The workshop provided critical insights on opportunities to improve market penetration of improved maize varieties. There is a need to strike a balance between the needs of the farmers, seed industry, and consumers in variety development; actively involve farmers and consumers in variety selection and understanding their preferences; and focus on emerging needs of the market such as yellow maize for feed and food,” said James Karanja, maize breeding lead at the Kenya Agriculture & Livestock Research Organization, Kenya.

Insights from both workshops underscored the importance of providing breeders with pertinent information and comprehensive training. The discussions illustrated the necessity for breeders to define their objectives with a 360-degree outlook, aligning breeding programs with market segments and interfacing with CIMMYT’s regional vision.

Workshop participants. (Photo: CIMMYT)

“The market intelligence workshop is an excellent initiative for the breeding programs. It shows how traits can be identified and prioritized, based on farmers’ requirements. The maize value chain is broad, and the synergy between the developer of the product (breeder), the producer (farmer), and the consumer needs to be effective. Hence, streamlining of the market segments and eventually the target product profiles is key in ensuring that the breeders develop improved products/varieties with relevant traits that address the needs of farmers, consumers, and the seed industry,” said Lubasi Sinyinda, breeder from the Zambia Agricultural Research Institute, Zambia.

Another participant, Lucia Ndlala, a maize breeder at the Agricultural Research Council, South Africa, echoed similar enthusiasm. “The workshop was exceptionally informative, providing valuable insights into target product profiles and market segments. This knowledge will undoubtedly prove instrumental in shaping future breeding strategies,” she said.

When applied through a breeding lens, market segmentation is a vital tool in refining breeding programs at both country and regional levels, enabling breeders to better understand and address the diverse needs of the farmers, and ensuring that the improved varieties are tailored to market segments.

Ten years later: CIMMYT facilities in East Africa continue to make a difference

CIMMYT and partners in Kenya recently marked the 10th anniversary of two major facilities that have been crucial for maize breeding in sub-Saharan Africa. The Maize Doubled-Haploid (DH) facility and the Maize Lethal Necrosis (MLN) screening facility at the Kenya Agriculture and Livestock Research Organization (KALRO) centers in Naivasha and Kiboko, respectively, have made immense contributions to the rapid development of higher-yielding, climate-resilient and disease-resistant maize varieties for smallholder farmers across the continent.

An aerial photo of the Naivasha Research Center. (Photo: CIMMYT)

“These two facilities have been instrumental in furthering KALRO’s mission to utilize technology in the service of Kenya’s smallholder farmers,” said KALRO Director General/CEO, Eliud Kireger. “They also exhibit the spirit of cooperation and collaboration that is necessary for us to meet all the challenges to our food systems.”

“Deploying a higher yielding maize variety may not be impactful in eastern Africa if that variety does not have resistance to a devastating disease like MLN,” said CIMMYT’s Director General Bram Govaerts. “These two facilities demonstrate the holistic methods which are key to working towards a more productive, inclusive and resilient agrifood system.”

Maize DH facility

Hybrid maize varieties have much higher yields than open-pollinated varieties and are key to unlocking the agricultural potential of maize producing countries. The doubled haploid process is an innovative technology producing within a year genetically true-to-type maize lines that serve as building blocks for improved maize hybrids.

Unlike conventional breeding, which takes at least 7 to 8 generations or crop seasons to develop parental lines, DH lines are generated within two seasons, saving significant time, labor and other resources. DH maize lines are highly uniform, genetically stable, and are more amenable to the application of modern molecular tools, making them perfect resources for breeding elite maize hybrids.

Workers in the Kiboko Double Haploid facility. (Photo: CIMMYT)

The aim of CIMMYT’s maize DH facility is to empower the breeding programs throughout the low-and middle-income countries in Africa by offering a competitive, accessible, not-for-profit DH production service that will accelerate their rate of genetic gain and fast-track development of improved maize varieties for farming communities.

Since 2017, the DH facility has delivered 280,000 DH lines from 1,840 populations of which 20% were delivered to public and private sector partners. CIMMYT maize breeding programs and partner organizations have embraced the use of DH technology, with many of the newest maize hybrids released in Africa being derived from DH lines. The facility has also served as a training ground so far for over 60 scientists and hundreds of undergraduate students in modern breeding technologies.

“Before 2013, DH technology was mainly employed by private, multinational corporations in North America, Europe, Asia and Latin America,” said CIMMYT’s DH Facility Manager, Vijay Chaikam. “But the DH facility operated by CIMMYT at the KALRO Kiboko research station is specifically targeted at strengthening the maize breeding programs by the public sector institutions as well as small-and medium-size enterprise seed companies in Africa.”

The maize DH facility at Kiboko, Kenya, was established with funding support from the Bill & Melinda Gates Foundation and inaugurated in September 2013. The facility includes an administrative building, seed quality laboratory, training resources, artificial seed dyer, a cold-storage seed room, a chromosome doubling laboratory, greenhouse and a state-of-the-art irrigation system to support year-round DH production in the 17-hectare nursery.

MLN screening facility

MLN is a devastating viral disease that can decimate farmers’ fields, causing premature plant death and unfilled, poorly formed maize ears, and can lead to up to 100 percent yield loss in farmers’ fields. Though known in other parts of the world for decades, the disease was first identified in eastern Africa in 2011. By 2015, MLN had rapidly spread across eastern Africa, including Kenya, Uganda, Tanzania, South Sudan, Rwanda, Democratic Republic of Congo and Ethiopia. CIMMYT scientists quickly discovered that almost all the commercial maize cultivars in eastern Africa were highly susceptible to the disease.

Against this backdrop, CIMMYT and KALRO recognized the urgent need for establishing a screening facility to provide MLN phenotyping service and effectively manage the risk of MLN on maize production through screening of germplasm and identifying MLN-resistant sources. The facility was built with funding support from the Bill & Melinda Gates Foundation and the Syngenta Foundation for Sustainable Agriculture, and inaugurated in September 2013.

Resistant and susceptible line at the Maize Lethal Necrosis facility. (Photo: CIMMYT)

“The MLN screening facility is a key regional resource in breeding for resistance to a devastating viral disease. The facility is indeed one of the key factors behind successful management of MLN and helping stem the tide of losses in eastern Africa,” said Director of the Global Maize Program at CIMMYT and One CGIAR Plant Health Initiative, B.M. Prasanna. “Fighting diseases like MLN, which do not respect political boundaries, requires strong regional and local collaboration. The successes achieved through the MLN Screening facility in the past 10 years embody that spirit of collaboration.” Indeed, farmers in the region now have access to over twenty genetically diverse, MLN-tolerant/resistant maize hybrids released in eastern and southern Africa.

The facility is the largest dedicated MLN screening facility in Africa and has evaluated over 230,000 accessions (over 330,000 rows of maize) from CIMMYT and partners, including over 15 national research programs, national and multinational seed companies. The facility covers 20 hectares, of which 17 hectares are used for field screening of germplasm. Dedicated laboratories and screen houses cover the remaining 3 hectares.

“MLN phenotyping service is conducted under stringent quarantine standards and the high-quality data is shared with all the CGIAR and public and private partners. The MLN screening service has helped breeding programs across the continent, aided in undertaking epidemiological research activities, and supported capacity building of students from diverse institutions, and regional stakeholders regarding MLN diagnosis and best management practices,” said CIMMYT’s Maize Pathologist in Africa, L.M. Suresh.

“The output of MLN resistant lines and hybrids has been remarkable,” said Director of Phytosanitary and Biosecurity at the Kenya Plant Health Inspectorate Service (KEPHIS), Isaac Macharia. “And the facility has strictly adhered to quarantine regulations.”

In Uganda, the MLN facility was crucial in the “release of the first-generation MLN tolerant hybrids and dissemination of MLN knowledge products that minimized the economic impact of MLN,” said the Director of Research of the National Crops Resources Research Institute, Godfrey Asea.

Peter Mbogo, maize breeder with Seed Co Group, said, “This is the only quarantine facility in the world where you can screen against MLN under artificial inoculation. It has been an excellent return on investment.”

Empowering women smallholder farmers in Africa with climate-resilient and nutritious maize varieties

In the vast landscapes of sub-Saharan Africa, where agriculture is the backbone of many communities, the quest for improved maize varieties is a vital step for ensuring food security in the face of climate change. Women, who represent approximately half the clients of maize breeding programs, have been essential in the realm of agricultural research. While significant gender-based differences in trait preferences exist in many African-staple crops, these appear less drastic in maize. However, there are gendered differences in management practices and productivity in maize-based systems.

After decades of work on maize improvement projects, CIMMYT has made a bigger commitment to researching, supporting and delivering drought and heat tolerant maize to smallholders in Zimbabwe. (Photo: CIMMYT)

Recognizing the need to bridge this gap, the CIMMYT-NARES (National Agricultural Research and Extension Systems) regional maize breeding networks in eastern and southern Africa have embarked on a transformative journey to empower farmers, especially women, through their innovative approach to maize breeding. The breeding networks are focused on ensuring smallholder farmers have access to a steady stream of climate-resilient and nutritionally enriched maize varieties that thrive in today’s stress-prone environments. To ensure these new maize varieties meet the needs of diverse users, including women, the breeding networks continue to adapt approaches to increase gender-responsiveness.

Linking science with the realities on the ground

Testing the performance of potential new maize hybrids coming from the breeding pipelines within farmers’ realities is critical to the ultimate success of these new varieties. In collaboration with over 400 farmers in southern Africa, the CIMMYT-NARES maize breeding network conducts extensive on-farm trials to evaluate the performance of these new maize varieties. A similar approach is adopted in eastern Africa. What sets these trials apart is the fact that over 40% of these trials are led by female plot managers. Farmers evaluate these varieties within the context of their own realities, including their own management practices, and provide valuable feedback to the breeding teams on the potential of new varieties.

By involving women in decision-making processes, CIMMYT-NARES networks ensure that their preferences and needs are considered when selecting the most promising hybrids for product advancement, announcement to partners, varietal releases and ultimately commercialization. This inclusive approach not only empowers women but also harnesses the collective knowledge and experience of the farming community. CIMMYT’s research recently showed that there is a relatively high degree of joint management within maize plots, and since 2022, the on-farm trials included a target of approximately 30% jointly managed plots.

Gender is only one axis of social difference that impacts agricultural production, variety selection, and end uses. Social differences including marital status, age, education level, ethnicity, wealth, access to capital, market access and livelihood orientation do play a role in the adoption of new varieties and farm productivity. By embracing the diversity within farming communities, CIMMYT-NARES networks are actively working towards understanding different farm types, while ensuring that the improved maize varieties are tailored to meet the diverse demands of the regions.

As the CIMMYT-NARES maize breeding networks continue to make innovative strides in breeding climate-resilient and nutritionally enriched maize varieties, they are not only transforming agriculture but also empowering individuals and communities. Through collaborative efforts, with the woman farmer at the heart of the approach, they are paving the way for a future where farming communities can thrive and contribute to food and nutritional security.

Exploring alternative solutions: the case for synthetic mulch in a changing world

Food security remains elusive for most smallholder farmers reliant on rainfed crop production, given the erratic rainfall patterns induced by climate change in Southern Africa. Among others, conservation agriculture (CA) is a concept often considered to be effective to adapt to these erratic rainfall patterns, enabling farmers to cope better with the prolonged dry spells that are characteristic of the semi-arid regions in Zimbabwe.

Conservation agriculture essentially involves three key pillars, namely, reduced soil disturbance, the use of crop rotations or intercrop associations, and the provision of permanent soil cover. The soil-cover component often requires the use of previous crop residues or other organic materials as a surface mulch. However, local farmers consider this task to be the most laborious aspect of implementing CA, which poses a significant challenge to its widespread uptake.

Collecting insights on influence of synthetic mulch. (Photo: CIMMYT)

Traditionally, farmers are advised to use organic mulch, such as maize residues, for soil cover. However, in most communal areas, there is a growing scarcity of organic mulches as they are predominantly used as livestock feed in mixed crop-livestock farming systems. Ironically, semi-arid regions that benefit from the use of crop residues as soil cover are also regions where the residues are the scarcest due to competing uses as livestock feed or as firewood. These competing interests pose a dilemma, as it is essential to cover the soil while also necessary to feed the animals. In neighboring countries like Malawi, maize residues are also used as fuel for firewood, further increasing the demand. It is clearly important, therefore, to develop alternative solutions to address this pressing issue.

“Since I embarked on my journey in conservation agriculture back in 1998, the matter of residues has been a topic of discussion. It is imperative that we walk the talk and develop practical solutions to meet the needs of farmers who rely on residues to feed their animals. One potential solution we are exploring is the use of synthetic mulches to cover the soil. By employing this method, we can cover the soil, apply fertilizer, and hopefully witness a positive impact. We certainly must develop synthetic materials that can be used sustainably as surface mulches in the semi-arid environments where organics are most scarce yet most needed,” stated Isaiah Nyagumbo, regional cropping systems agronomist.

To test such innovations, some water-conservation experiments were established in Buhera and Mutoko, Zimbabwe, during the last two seasons, and the results have been encouraging.

“I am grateful to work with the CIMMYT team on these water conservation trials, and I hope they continue. Before the trials, we were using organic mulch, but after using the synthetic approach and comparing it with organic mulches and none at all, we are seeing so many positive results. But there are challenges we can’t escape, including affordability. But I have seen higher yield returns this year as I harvested close to 15 by 50kgs of maize,” said Nyawasha, a farmer from Mutoko, Zimbabwe, ward 16.

Further detailed studies to understand these systems have also been established in the current dry season at the CIMMYT campus in Harare, to test the effectiveness of these synthetic mulches under conditions of severe moisture stress. The different treatments include clear synthetic mulch, black synthetic mulch, organic mulch and no mulch. So far, for the maize crop now at flowering stage, the growth and yield are strikingly better in plots under the synthetic mulches compared with the organic and no mulch plots. This clearly shows the importance of finding viable alternatives. The crop with synthetic mulches also developed much faster, all the way from crop emergence.

Exploring the tied-ridging system

In these trials, mulching treatments are being tested in conventionally tilled plots, CA basins (pfumvudza basins) and under the tied-ridging system. Tied ridging has been developed in Zimbabwe for use by smallholder farmers since the 1980s and is well known for its effectiveness in reducing sheet erosion and water run-off. This system employs ridges 15–20 cm high, with crossties in the furrows at 1–2 m intervals that trap rainwater and prevent runoff and soil erosion. However, in a typical rainfed system, poor germination challenges can arise when planting on top of these ridges due to excessive drying of moisture from the raised ridges. Furthermore, during prolonged dry spells, the exposed ridges tend to cause crops to wilt more than flat-planted conventional crops. To address these issues, scientists at CIMMYT in Zimbabwe are also exploring innovative ways to improve the tied-ridging system through ways that minimize water loss through direct soil evaporation.

“This has been one of the shortcomings of the tied-ridging system, and we need ways to overcome this excessive moisture evaporation. Once the water has gone into the soil, it should only leave through plant uptake and not be wasted through direct soil evaporation,” said Nyagumbo.

Integrating synthetic mulch into the tied-ridge system. (Photo: CIMMYT)

One approach being considered is incorporating mulch into the system to reduce evaporation and ensure that captured water is retained. The results are evident in the vibrant greenery of the plants with mulch compared with those without. Observing the number of plants with tassels and silk, it is clear that the plots with clear synthetic material have faster growth and reach maturity sooner compared with the plots with black synthetic mulch.

“My outlook on the use of synthetic mulch on ridges is that they are much more effective, as it makes the soil very loose for good aeration to the plant and encourages high growth rate. I noticed that plants germinated in three days and the little water provided will directly benefit the plant without escaping. I am encouraged to continue doing this tied ridge approach using synthetic material,” said Nyekete, a farmer in Buhera, Zimbabwe, ward 7.

While exploring various options, it has also been important to prioritize and focus on one aspect at a time. The initial focus has been on maize residue, as it is a valuable resource for both soil cover and livestock feed. However, the scarcity of maize residue poses a significant challenge for many farmers, especially in regions like Buhera, Mberengwa and Shurugwi, where animals consume all available resources. Placing maize residues in open fields is not a very viable solution, as freely roaming livestock will just consume it. Fencing or creating structures to protect the residues from livestock also requires substantial effort and resources, thereby making this mulching a daunting task for farmers.

Food for thought

While the challenges faced in providing mulch for conservation agriculture are multifaceted, there is a growing need to develop innovative solutions that address the scarcity of organic mulch and explore alternative methods such as synthetic coverings. By continuously adapting and refining our practices, we can ensure the sustainability of agriculture in this region and improve the livelihoods of farmers.

A Mexican farm research program gains praise and interest for use abroad

Leveraging the leadership, science, and partnerships of the Mexico-based CIMMYT and the funding and research capacity of Mexico’s Secretariat of Agriculture and Rural Development (SADER) during 2010-21, the program known asMasAgro” has helped up to 500,000 participating farmers to adopt improved maize and wheat varieties and resource-conserving practices on more than 1 million hectares of farmland in 30 states of Mexico.

Tlaltizapan Experimental Station in Morelos, Mexico is used through the winter for drought and heat trials and through the summer for yield-trials and biofortification. (Photo: Alfonso Cortés/CIMMYT)

As a result of MasAgro research hubs operating across Mexico’s multiple and diverse agroecologies to promote the sustainable intensification of maize and wheat farming systems — including improved varieties and resource-conserving, climate-smart practices — yields of project participants for maize were 20% higher and for wheat 3% higher than local averages. Similarly, average net incomes for participating maize farmers were 23% greater and 4% greater for wheat farmers, compared to local averages.

The MasAgro biodiversity component gathered and analyzed one of the world’s largest-ever samplings of maize and wheat genetic diversity, including CIMMYT’s own vast seed bank collections, to help identify and characterize new genes of interest for breeding. As one result, more than 2 billion genetic data points and over 870,000 data entries from associated field trials are freely available to the scientific community, via the project’s online repository.

MasAgro has involved national and local research organizations, universities, companies, and non-government organizations working through more than 40 research platforms and 1,000 demonstration modules, while building the capacity of thousands of farmers and hundreds of technical and extension experts who serve them.

State-level partners sign on to MasAgro

Through MasAgro, CIMMYT entered into research and development partnerships with 12 Mexican states. An example is the mountainous, central Mexican state of Guanajuato, home to the El Bajío region, one of Mexico’s most productive farm areas but which also suffers from soil degradation, water scarcity, and climate change effects — challenges faced by farmers throughout Mexico. The governor of Guanajuato visited CIMMYT headquarters in Mexico in June 2023 to review progress and agree on follow-up activities.

MasAgro generated more sustainable production and irrigation systems in Guanajuato, Mexico. (Photo: ACCIMMYT)

CIMMYT has worked with Guanajuato state and local experts and farmers themselves to test and promote innovations through 7 research platforms reaching nearly 150,000 hectares. As of 2020, new crop varieties and resource-conserving, climate-smart management practices had helped underpin increases of 14% in irrigated wheat production and, under rainfed farming systems, improved outputs of 28% for beans, 150% for local maize varieties and 190% for hybrid maize, over state averages.

An integral soil fertility initiative has included the analysis and mapping of more than 100,000 hectares of farmland, helping Guanajuato farmers to cut costs, use fertilizer more effectively, and reduce the burning of crop residues and associated air pollution.

Service centers for the rental and repair of conservation agriculture machinery are helping to spread practices such as zero tillage and residue mulches. Supported by CIMMYT advisors, Guanajuato farmers are entering into equitable and ecologically friendly production agreements with companies such as Nestle, Kellogg’s, and Heineken, among other profitable and responsible public-private arrangements.

Acclaim and interest abroad for MasAgro

MasAgro has received numerous awards and mentions as a model for sustainable agricultural development. A few examples:

Dignitaries applaud MasAgro launch at CIMMYT. (Photo: Xochiquetzal Fonseca/CIMMYT)
  • The Inter-American Development Bank (IDB) mentioned the program as an example of successful extension.
  • The Organization for Economic Cooperation and Development (OECD) cited MasAgro for promoting productive and sustainable agriculture.
  • The United Nations Development Program (UNDP) lauded MasAgro for promoting climate-resilient agriculture.
  • During the 2018 G20 summit in Argentina, MasAgro was considered a model for coordinating agricultural research, development, innovation, technology transfer, and public-private partnerships.
  • Bram Govaerts, now Director General of CIMMYT, received the 2014 Norman Borlaug Field Award for his work at the time as leader of MasAgro’s farmer outreach component.
  • MasAgro research hubs were recently used as a guide by USAID for efforts in Sudan and Eastern Africa. They have also been replicated in Guatemala and Honduras.

Moving out and beyond

In Central America and Mexico, the inter-connected crises of weak agri-food systems, climate change, conflict, and migration have worsened, while small-scale farmers and marginalized sectors remain mired in poverty.

Capitalizing on its experience in MasAgro, CIMMYT is a major partner in the recently launched CGIAR initiative, AgriLAC Resiliente, which aims to build the resilience, sustainability, and competitiveness of agrifood systems and actors in Latin America and the Caribbean, helping them to meet urgent food security needs, mitigate climate hazards, stabilize vulnerable communities, and reduce forced migration. The effort will focus on farmers in Colombia, El Salvador, Honduras, Mexico, Nicaragua, and Peru.

Farmer Marilu Meza Morales harvests her maize in Comitán, Mexico. (Photo: Peter Lowe/CIMMYT)

As described in a 2021 science journal article, CIMMYT also helped create the integrated agri-food system initiative (IASI), a methodology that was developed and validated through case studies in Mexico and Colombia, and leverages situation analysis, model predictions, and scenarios to synchronize public and private action toward sustainable, equitable, and inclusive agri-food systems.

“CIMMYT’s integrated development approach to maize system transformation in Mexico and Colombia laid the foundations for the IASI methodology by overcoming government transitions, annual budget constraints, and win-or-lose rivalries between stakeholders, in favor of equity, profitability, resilience and sustainability,” said Govaerts.

The 2021 Global Agricultural Productivity (GAP) report “Strengthening the Climate for Sustainable Agricultural Growth” endorsed IASI, saying it “…is designed to generate strategies, actions and quantitative, Sustainable-Development-Goals-aligned targets that have a significant likelihood of supportive public and private investment.”

SPG Coalition: CIMMYT is a leading organization for climate-smart agriculture, nutrient-use efficiency, and pest and fertilizer management

The Coalition on Sustainable Productivity Growth for Food Security and Resource Conservation (SPG Coalition) brings together researchers, non-governmental organizations, and private sector partners to advance a world with greater access to nutritious food and affordable diets. The Coalition recognizes that increasing the productivity of natural resources through climate adaptation and mitigation is instrumental to reaching this goal.

In a recent report, the SPG Coalition provides a path forward for NGOs, research institutions, and government agencies to strengthen agrifood and climate policies. The report contains real-life, evidence-based examples to further the sustainable production and conservation of natural resources, detailing the potential impacts on social, economic, and environmental conditions.

CIMMYT features prominently in the report as a leading organization focused on 4 main areas: climate-smart agriculture, nutrient-use efficiency (NUE), and pest and fertilizer management.

Nutrient-use efficiency and fertilizer management

While chemical fertilizers increase crop yields, excessive or improper use of fertilizers contributes to greenhouse gas emissions (GHG) and increases labor costs for smallholders. Efficient NUE is central to nutrient management and climate change mitigation and adaptation.

Women using spreader for fertilizer application. (Photo: Wasim Iftikar/CSISA)

In India, CIMMYT, along with the Borlaug Institute for South Asia (BISA), CGIAR Research Centers, and regional partners, tested digital tools like the Nutrient Expert (NE) decision support tool which measures proper fertilizer use for optimized yields and provides nutrient recommendations based on local soil conditions.

The majority of smallholders who applied the NE tool reported higher yields while emitting less GHG emissions by 12-20% in wheat and by around 2.5% in rice as compared with conventional fertilization practices. Farmers also recorded double economic gains: increased yields and reduced fertilizer costs. Wider government scaling of NE could enhance regional food security and mitigate GHG emissions.

The Feed the Future Nepal Seed and Fertilizer (NSAF) project, led by CIMMYT and USAID, advocates for climate-smart agriculture by linking smallholders with improved seed, providing capacity-building programs, and promoting efficient fertilizer use. With a vast network established with the support from the Government of Nepal, NSAF successfully provides smallholders with expanded market access and nutritious and climate-resilient crop varieties.

Climate-smart maize breeding 

Since its arrival to sub-Saharan Africa (SSA) in 2016, fall armyworm (FAW) has devastated maize harvests for countless smallholders on the continent. Economic uncertainty caused by unstable yields and climate stressors like drought coupled with this endemic pest risk aggravating food insecurity.

Fall armyworm. (Photo: Jennifer Johnson/CIMMYT)

CIMMYT and NARES Partner Institutions in Eastern and Southern Africa are spearheading a robust pest management project to develop, screen, and introduce genetically resistant elite maize hybrids across SSA. South Sudan, Zambia, Kenya, and Malawi have already deployed resistant maize varieties, and eight other countries in the region are projected to release their own in 2023. These countries are also conducting National Performance Trials (NPTs) to increase awareness of host plant resistance for the sustainable control of FAW and to sensitize policymakers on accelerating the delivery of FAW-tolerant maize varieties.

The establishment of FAW screening facilities in Africa permits more rapid detection and breeding of maize varieties with native genetic resistance to FAW, facilitating increased deployment of these varieties across Africa. The sustainable control of FAW demands a rapid-response effort, overseen by research organizations and governments, to further develop and validate genetic resistance to fall armyworms. Achieving greater impact for maize smallholders is critical to ensuring improved income and food security in Africa. It is also paramount for biodiversity conservation and removing labor burden on farmers applying additional synthetic pesticides to prevent further losses by the pest.

“The SPG Coalition report emphasizes the power of partnership to enhance financial and food security for smallholder communities in the Global South. This is fully in line with the recently launched CIMMYT 2030 strategy. It’s also an important reminder to assess our strong points and where more investment and collaboration is needed,” said Bram Govaerts, CIMMYT director general.