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research: Maize

A view from above

Written by Alison Doody on . Posted in Features.

Scientists at the International Maize and Wheat Improvement Center (CIMMYT) have been harnessing the power of drones and other remote sensing tools to accelerate crop improvement, monitor harmful crop pests and diseases, and automate the detection of land boundaries for farmers.

A crucial step in crop improvement is phenotyping, which traditionally involves breeders walking through plots and visually assessing each plant for desired traits. However, ground-based measurements can be time-consuming and labor-intensive.

This is where remote sensing comes in. By analyzing imagery taken using tools like drones, scientists can quickly and accurately assess small crop plots from large trials, making crop improvement more scalable and cost-effective. These plant traits assessed at plot trials can also be scaled out to farmers’ fields using satellite imagery data and integrated into decision support systems for scientists, farmers and decision-makers.

Here are some of the latest developments from our team of remote sensing experts.

An aerial view of the Global Wheat Program experimental station in Ciudad ObregĂłn, Sonora, Mexico (Photo: Francisco Pinto/CIMMYT)

Measuring plant height with high-powered drones

A recent study, published in Frontiers in Plant Science validated the use of drones to estimate the plant height of wheat crops at different growth stages.

The research team, which included scientists from CIMMYT, the Federal University of Viçosa and KWS Momont Recherche, measured and compared wheat crops at four growth stages using ground-based measurements and drone-based estimates.

The team found that plant height estimates from drones were similar in accuracy to measurements made from the ground. They also found that by using drones with real-time kinematic (RTK) systems onboard, users could eliminate the need for ground control points, increasing the drones’ mapping capability.

Recent work on maize has shown that drone-based plant height assessment is also accurate enough to be used in maize improvement and results are expected to be published next year.

A map shows drone-based plant height estimates from a maize line trial in Muzarabani, Zimbabwe. (Graphic: CIMMYT)

Advancing assessment of pests and diseases

CIMMYT scientists and their research partners have advanced the assessment of Tar Spot Complex — a major maize disease found in Central and South America — and Maize Streak Virus (MSV) disease, found in sub-Saharan Africa, using drone-based imaging approach. By analyzing drone imagery, scientists can make more objective disease severity assessments and accelerate the development of improved, disease-resistant maize varieties. Digital imaging has also shown great potential for evaluating damage to maize cobs by fall armyworm.

Scientists have had similar success with other common foliar wheat diseases, Septoria and Spot Blotch with remote sensing experiments undertaken at experimental stations across Mexico. The results of these experiments will be published later this year. Meanwhile, in collaboration with the Federal University of Technology, based in Parana, Brazil, CIMMYT scientists have been testing deep learning algorithms — computer algorithms that adjust to, or “learn” from new data and perform better over time — to automate the assessment of leaf disease severity. While still in the experimental stages, the technology is showing promising results so far.

CIMMYT researcher Gerald Blasch and EIAR research partners Tamrat Negash, Girma Mamo and Tadesse Anberbir (right to left) conduct field work in Ethiopia. (Photo: Tadesse Anberbir)

Improving forecasts for crop disease early warning systems

CIMMYT scientists, in collaboration with Université catholique de Louvain (UCLouvain), Cambridge University and the Ethiopian Institute of Agricultural Research (EIAR), are currently exploring remote sensing solutions to improve forecast models used in early warning systems for wheat rusts. Wheat rusts are fungal diseases that can destroy healthy wheat plants in just a few weeks, causing devastating losses to farmers.

Early detection is crucial to combatting disease epidemics and CIMMYT researchers and partners have been working to develop a world-leading wheat rust forecasting service for a national early warning system in Ethiopia. The forecasting service predicts the potential occurrence of the airborne disease and the environmental suitability for the disease, however the susceptibility of the host plant to the disease is currently not provided.

CIMMYT remote sensing experts are now testing the use of drones and high-resolution satellite imagery to detect wheat rusts and monitor the progression of the disease in both controlled field trial experiments and in farmers’ fields. The researchers have collaborated with the expert remote sensing lab at UCLouvain, Belgium, to explore the capability of using European Space Agency satellite data for mapping crop type distributions in Ethiopia. The results will be also published later this year.

CIMMYT and EIAR scientists collect field data in Asella, Ethiopia, using an unmanned aerial vehicle (UAV) data acquisition. (Photo: Matt Heaton)

Delivering expert irrigation and sowing advice to farmers phones

Through an initiative funded by the UK Space Agency, CIMMYT scientists and partners have integrated crop models with satellite and in-situ field data to deliver valuable irrigation scheduling information and optimum sowing dates direct to farmers in northern Mexico through a smartphone app called COMPASS — already available to iOS and Android systems. The app also allows farmers to record their own crop management activities and check their fields with weekly NDVI images.

The project has now ended, with the team delivering a webinar to farmers last October to demonstrate the app and its features. Another webinar is planned for October 2021, aiming to engage wheat and maize farmers based in the Yaqui Valley in Mexico.

CIMMYT researcher Francelino Rodrigues collects field data in Malawi using a UAV. (Photo: Francelino Rodrigues/CIMMYT)

Detecting field boundaries using high-resolution satellite imagery

In Bangladesh, CIMMYT scientists have collaborated with the University of Buffalo, USA, to explore how high-resolution satellite imagery can be used to automatically create field boundaries.

Many low and middle-income countries around the world don’t have an official land administration or cadastre system. This makes it difficult for farmers to obtain affordable credit to buy farm supplies because they have no land titles to use as collateral. Another issue is that without knowing the exact size of their fields, farmers may not be applying to the right amount of fertilizer to their land.

Using state of the art machine learning algorithms, researchers from CIMMYT and the University of Buffalo were able to detect the boundaries of agricultural fields based on high-resolution satellite images. The study, published last year, was conducted in the delta region of Bangladesh where the average field size is only about 0.1 hectare.

A CIMMYT scientist conducts an aerial phenotyping exercise in the Global Wheat Program experimental station in Ciudad ObregĂłn, Sonora, Mexico. (Photo: Francisco Pinto/CIMMYT)

Developing climate-resilient wheat

CIMMYT’s wheat physiology team has been evaluating, validating and implementing remote sensing platforms for high-throughput phenotyping of physiological traits ranging from canopy temperature to chlorophyll content (a plant’s greenness) for over a decade. Put simply, high-throughput phenotyping involves phenotyping a large number of genotypes or plots quickly and accurately.

Recently, the team has engaged in the Heat and Drought Wheat Improvement Consortium (HeDWIC) to implement new high-throughput phenotyping approaches that can assist in the identification and evaluation of new adaptive traits in wheat for heat and drought.

The team has also been collaborating with the Accelerating Genetic Gains in Maize and Wheat (AGG) project, providing remote sensing data to improve genomic selection models.

Cover photo: An unmanned aerial vehicle (UAV drone) in flight over CIMMYT’s experimental research station in Ciudad Obregon, Mexico. (Photo: Alfredo Saenz/CIMMYT)

Pauline Muindi, gender research associate with CIMMYT, at the mock agrodealer shop where she acted as a clerk. (Photo: CIMMYT)

Buying into new seed

Written by Rodrigo Ordóñez on . Posted in Features.

Mary Nzau enters a mock agrodealer shop set up on a field on the outskirts of Tala town in Machakos County, Kenya. On display are nine 2kg bags of hybrid maize seed. She picks one. By the look of it, her mind is made up. After a quick scan of the shelf, she has in her hand the variety that she has been purchasing for years.

Regina Mbaika Mutua is less lucky. The variety she always buys is not on display in the mock shop. As part of the experiment, the research team has removed from the shelf the variety she indicated she usually buys. The team’s goal is to observe what factors influence her seed purchase decision in the absence of the variety she was expecting to purchase.

“Although I did not find the variety I was looking for, I picked an alternative as I have seen it perform well on a neighboring farm,” Mutua says, adding that she will plant it this season alongside recycled (farm-saved) seed on her one-acre farm.

Michael Mutua passes up the popular variety he has been planting for the previous two years. He picks one that has been advertised extensively on local radio. “I have heard about it severally on radio. I would like to experiment with this new seed and see how it performs on my farm. Should I like the results, I will give it a chance in ensuing seasons,” he says.

Pieter Rutsaert explains the study setup at a mock agrodealer shop. (Photo: Joshua Masinde/CIMMYT)
Pieter Rutsaert explains the study setup at a mock agrodealer shop. (Photo: Joshua Masinde/CIMMYT)

The big adoption conundrum

The goal of the out-of-stock study is to improve an understanding of how farmers make their maize seed choices, says Pieter Rutsaert, Markets and Value Chain Specialist at the International Maize and Wheat Improvement Center (CIMMYT).

“We do this by inviting farmers to a mock agrodealer store that we set up in their villages and give them a small budget to purchase a bag of seed. However, not all farmers walk into the same store: some will find their preferred variety, others won’t. Some will have access to additional trait information or see some varieties with price promotions while others don’t.”

Rutsaert acknowledges that breeding programs and their partner seed companies have done a great job at giving farmers access to maize hybrids with priority traits such as drought tolerance and high yield. CIMMYT then works closely with local seed companies to get varieties into the hands of farmers. “We want to extend that support by providing insights to companies and public breeding programs on how to get new varieties more quickly into the hands of farmers,” he says.

Pauline Muindi (left), gender research associate with CIMMYT, acts as a mock agrodealer clerk and attends a farmer. (Photo: CIMMYT)
Pauline Muindi (left), gender research associate with CIMMYT, acts as a mock agrodealer clerk and attends a farmer. (Photo: CIMMYT)

The hybrid maize seed sector in Kenya is highly competitive. Amid intensifying competition, new varieties face a daunting task breaking into the market, independent of their quality. While farmers now have more options to pick from, a major challenge has been how to get them to adopt new varieties.

“Moving farmers from something they know to something they don’t is not easy. They tend to stick with what they know and have been growing for years,” Rutsaert says.

Pauline Muindi, gender research associate with CIMMYT, acted as the stand-in clerk at the mock store. She noticed that farmers tend to spend very little time in the shop when their preferred variety is available. However, this all changes in the out-of-stock situation, pushing farmers to step out of their comfort zone and explore new options.

The first step to overcoming this challenge is to entice maize farmers to try a new seed variety, even just once, Rutsaert observes. If it is a good variety, farmers will see that and then the market will work in its favor: farmers will come back to that variety in subsequent years and tell others about it.

“The good news is that many of the varieties we are currently seeing on the market have performed well — that’s why they’re popular. But there are newer varieties that are even better, especially in terms of attributes like drought tolerance. We would like to understand how farmers can be convinced to try out these newer varieties. Is it about the need for more awareness on varietal traits? Can we use price promotions? Or are there other factors?” he says.

A researcher interviews Mary Nzau (right), a farmer from Tala town in Machakos County, after her mock purchase. (Photo: Joshua Masinde/CIMMYT)
A researcher interviews Mary Nzau (right), a farmer from Tala town in Machakos County, after her mock purchase. (Photo: Joshua Masinde/CIMMYT)

Does seed price matter?

“With today’s climate uncertainty, it is better to stick to a variety that is adapted to such climate rather than banking on a variety one is oblivious of. The risk is not worth it,” Nzau says. She adds that she would rather buy a higher-priced seed packet she knows and trusts than a lower-priced one that she has not used in the past. Radio promotions of new or other varieties have limited sway over her decision to make the switch.

Faith Voni, another farmer, agrees. “It is better to purchase a higher-priced variety whose quality I can vouch for than risk purchasing a lower-priced one that I know little about. I do not wish to take such a risk.” Voni says she would also be more inclined to experiment with another variety that she had seen perform well on a neighbor’s farm.

Michael Mutua holds a different view. “If there is an option of an equally good but new variety that is lower-priced than the variety I prefer, my wallet decides,” he says.

Vivian Hoffmann, an economist at the International Food Policy Research Institute (IFPRI) and collaborator on the study, says price can be key for convincing consumers to try a new product. “Our previous research on maize flour choice found that a provisional 10 percent discount boosted sales tremendously,” Hoffmann says. “Of course, that only gets your foot in the door; after that, a new variety will need to win farmers over based on its merits.”

Hoffmann is interested in the extent to which drawing farmers’ attention to key varietal attributes influences their seed choice. “This information is generally already available on seed packets, but we live in a world of information overload. Promoting certain attributes through in-store signage is an approach that is widely used to help consumers make more healthier food choices. Doing the same for new seed varieties makes a lot of sense.”

Michael Mutua (left) responds to preliminary questions from one of the research team members before proceeding to make his seed selection at the mock agrodealer shop. (Photo: Joshua Masinde/CIMMYT)
Michael Mutua (left) responds to preliminary questions from one of the research team members before proceeding to make his seed selection at the mock agrodealer shop. (Photo: Joshua Masinde/CIMMYT)

The value of drought tolerance

Situated on Kenya’s eastern region, Machakos is characterized by persistent water stress. Climate change induced erratic rainfall has pushed traits that can tolerate the unfavorable weather conditions in the favorite’s corner. While other traits such as high yield and disease resistance are equally important, the seed, when planted, must first withstand the effects of droughts or water stress in some seasons and germinate. This is the most crucial step in the long journey to either a decent, bare minimum or no yield. A lot of farmers still plant recycled seed alongside hybrid varieties. But these are no match to water stress conditions, which decimate fields planted with farmer-saved seed.

“If a variety is not climate resilient, I will likely not harvest anything at all,” says Nzau. She has planted a drought-tolerant variety for ten years now. Prior to that, she had planted about three other varieties as well as recycled seed. “The only advantage with recycled seed is that given the right amount of rainfall, they mature fast — typically within two months. This provides my family with an opportunity to eat boiled or roast maize,” she notes.

However, varieties need to do more than just survive harsh weather conditions. Breeders face a daunting task of incorporating as many traits as possible to cater to the overarching and the specific interests of multiple farmers. As Murenga Mwimali, a maize breeder at the Kenya Agricultural and Livestock Research Organization (KALRO) and collaborator in this research says, innovations in breeding technologies are making breeding more efficient.

“It is better to have a diversity of product profiles as different market niches are captured within a particular agroecological zones. This is such that farmers may not just benefit from the minimum traits like drought tolerance, but also more specific traits they are looking for,” Mwimali says.

Smallholder farmers continue to play a central role in the seed development process. Capturing what happens at the point of purchase, for instance, at the agrodealer, and understanding how they purchase seed offers valuable insights on the traits that are deemed essential in the breeding process. This work contributes to CIMMYT’s focus on fast-tracking varietal turnover by turning the levers towards a demand-driven seed system.

Cover photo: Pauline Muindi, gender research associate with CIMMYT, at the mock agrodealer shop where she acted as a clerk. (Photo: CIMMYT)

Terry Molnar sits for a portrait with his dog. (Photo: Alfonso Cortés/CIMMYT)

Four questions with CIMMYT’s Maize Genebank Curator

Written by Marta Millere on . Posted in Videos.

Seeds are a cornerstone of food security. That is why the maize and wheat genebanks have always been at the heart of the work of the International Maize and Wheat Improvement Center (CIMMYT).

Earlier this year, as the CIMMYT community wished farewell to Denise Costich, Terence (Terry) Molnar stepped into her shoes and took over the management of the world’s largest and most diverse collection of maize.

Molnar calls himself a curator, but unlike his counterparts at libraries and museums, his job is not only about registering and showcasing the 28,000 unique seed collections of maize. He and his team make sure that the rich maize biodiversity collected throughout time and geographies stays alive, viable and accessible to others.

We sat down with Molnar to learn more about his unique role and what we can do to celebrate biodiversity on the International Day for Biological Diversity — and every other day.

Maize ears of the newly released set of CIMMYT maize lines. (Photo: CIMMYT)

CIMMYT releases 12 new maize lines

Written by Rodrigo Ordóñez on . Posted in News.

Maize ears of the newly released set of CIMMYT maize lines. (Photo: CIMMYT)
Maize ears of the newly released set of CIMMYT maize lines. (Photo: CIMMYT)

The International Maize and Wheat Improvement Center (CIMMYT) is pleased to announce the release of a set of 12 new CIMMYT maize lines (CMLs). These lines were developed at various breeding locations of CIMMYT’s Global Maize program by a multi-disciplinary team of scientists in sub-Saharan Africa and Asia. The lines are adapted to the tropical maize production environments targeted by CIMMYT and partner institutions.

CIMMYT seeks to develop improved maize inbred lines in different product profiles, with superior performance and multiple stress tolerance to improve maize productivity for smallholder farmers. CMLs are released after intensive evaluation in hybrid combinations under various abiotic and biotic stresses, besides optimum conditions.  Suitability as either seed or pollen parent is also thoroughly evaluated.

To increase the utilization of the CMLs in maize breeding programs of partner institutions, all the new CMLs have been tested for their heterotic behavior and have been assigned to specific heterotic groups of CIMMYT: A and B. As a new practice, the heterotic group assignment is included in the name of each CML, after the CML number — for example, CML604A or CML605B.

Release of a CML does not guarantee high combining ability or per se performance in all environments. Rather, it indicates that the line is promising or useful as a parent for pedigree breeding or as a potential parent of hybrid combinations for specific mega-environments. The description of the lines includes heterotic group classification, along with information on their specific strengths, and their combining ability with some of the widely used CMLs or CIMMYT lines.

Plants of the newly released set of CIMMYT maize lines. (Photo: CIMMYT)
Plants of the newly released set of CIMMYT maize lines. (Photo: CIMMYT)

More information:

Summary of the characteristics of the 12 new CMLs (PDF).

Pedigree and characterization data of all the CMLs released to date, including the latest set (CIMMYT Research Data repository).

Seed requests:

A limited quantity of seed of the CMLs can be obtained by sending a request to the CIMMYT Maize Germplasm Bank. CMLs are freely available to both public and private sector breeders worldwide under the Standard Material Transfer Agreement.

Contact:

For further details regarding the released CMLs, please contact B.M. Prasanna, Director of the Global Maize Program, CIMMYT, and the CGIAR Research Program on Maize.

Breaking Ground: Natalia Palacios gets the most out of maize

Written by Steven M on . Posted in Features.

It’s often joked that specialists learn more and more about less and less until they know everything about nothing, while for generalists it’s just the opposite.

In the case of Natalia Palacios, neither applies. She may have the word specialist in her title — she is a maize quality specialist at the International Maize and Wheat Improvement Center (CIMMYT) — but throughout her career she has had to learn more and more about a growing range of topics.

As leader of the Nutrition Chapter of the Integrated Development Program and head of the Maize Quality Laboratory, Palacios’ job is to coordinate CIMMYT’s efforts to ensure that maize-based agri-food systems in low- and middle-income countries are as healthy and nutritious as possible. The scope of this work spans the breadth of maize-based agri-food systems — from seed to supper.

“What ultimately matters for human health and nutrition is the nutritional quality of the final product,” says Palacios. “High quality, nutritious grain is an important part of the puzzle, but so are the nutritional effects of various post-harvest storage, processing, and cooking techniques.”

Natalia Palacios (front, center) with colleagues on CIMMYT’s Quality Maize team during an Open House event at CIMMYT HQ. (Photo: Alfonso CortĂ©s/CIMMYT)

Seeing the forest and the trees

Originally from Bogota, Colombia, Palacios studied microbiology at the Universidad de los Andes before pursuing a PhD in plant biology at the University of East Anglia and the John Innes Centre in the United Kingdom.

“I had the opportunity to work as research assistant at the International Center for Tropical Agriculture (CIAT) in Cali, Colombia,” she explains. “The exposure to interdisciplinary and international teams working for agricultural development and the leadership of my boss at that time, Joe Tohme, not only helped convince me to pursue post graduate studies in plant biology, they fostered an excitement around the real-world applications of scientific research.”

When she joined CIMMYT in 2005, Palacios worked on maize biofortification, supporting efforts to breed maize varieties rich in provitamin A and zinc. With time, she found her attention shifting towards the effect of food processing on the nutritional quality of maize-based food products, as well as to the importance of maize safety. For example, for a recent project, Palacios and her team have been analyzing the effect of a traditional thermal alkaline maize treatment known as nixtamalization on the physical composition of the grain and the nutritional quality of end products. Because of its important benefits, they are promoting this ancient technique in other geographies.

For Palacios, shifts such at this are completely in keeping with the overall goal of her work. “The main challenge we face as agricultural researchers is contributing to a nutritious, affordable diet produced within planetary boundaries,” she says. “Tackling any part of this challenge requires us to communicate between disciplines, to look at agri-food systems as a whole, and to link production and consumption.”

At the same time, for Palacios, the beauty of her work lies in going deep into a specific research question before bringing her focus back to the big picture. This movement between the specific and the general keeps her motivated, generates new questions and avenues of research, and keeps her from falling into silver-bullet thinking.

For example, her work on provitamin A biofortified maize led her to ask questions about how much of the vitamin reached consumers depending on how the grain was stored and handled. The vitamin is prone to degradation through oxidation. This led to storage and processing recommendations meant to maximize the crop’s nutritional value, including storing provitamin A maize as grain and milling it as late as possible before consumption. Researchers also worked to identify germplasm with more stable provitamin A carotenoids to be used in the breeding program.

In one study, Palacios and her coauthors found that feeding biofortified maize to hens increased the provitamin A value of their eggs, suggesting that for rural households the nutritional benefits of the improved grain could be spread out across different foodstuffs.

Natalia Palacios extracts carotenoids from maize kernels in a CIMMYT lab in Mexico. (Photo: Alfonso Cortés/CIMMYT)

Bringing it all together

In a paper published last spring, Palacios and her co-authors bring together the insights of these various avenues of research into one comprehensive review. The point, Palacios explains “was to identify opportunities to exploit the nutritional benefits of maize — a grain largely consumed in Africa, Latin America and some parts of Asia as important part of a diet — from understanding how to leverage the its genetic diversity for the development of more nutritious varieties to mapping all the different parts of the food system where nutritional gains can be made.”

The paper encompasses sections on the biochemistry of maize, maize breeding, maize-based foodways and culture, and traditional agronomic practices like milpa intercropping. It exemplifies Palacios’ interdisciplinary approach and her commitment to exploring multiple, interconnected pathways towards more nutritious maize agri-food systems.

As CGIAR’s 2030 Research and Innovation Strategy makes clear with its emphasis on the need for a systems-level transformation of food, land and water systems, this approach is timely and much needed.

In Palacios’ words: “Food security, nutrition and food safety are inextricably linked, and we must address them from the field to the plate and in a sustainable way.”

 

World Health Day 2021

Written by Emma Orchardson on . Posted in Features.

Health has certainly been in the spotlight over the past year. And how could it not be?

The ongoing COVID-19 pandemic has thrown into sharp relief the fact that many groups across the world struggle to make ends meet with little daily income, have poorer housing conditions and education, fewer employment opportunities, and have little or no access to safe environments, clean water and air, food security and health services.

In light of this, the World Health Organization (WHO) is calling on leaders worldwide to ensure that everyone has living and working conditions that are conducive to good health. For many the focus will, understandably, be on access to quality health care services. But there are myriad other factors that influence our ability to lead healthy lives — from how we care for our soil, to what we eat and the air we breathe.

Joining this year’s World Health Day campaign, the International Maize and Wheat Improvement Center (CIMMYT) is highlighting five areas where it pays to think about health, and the solutions we can use to help build a healthier world for everyone.

It starts with soil

Crop yields fall dramatically when soil conditions aren’t right, but digital nutrient management tools providing tailored fertilizer recommendations can boost farmers’ profits and productivity while reducing emissions.

Douglas Mungai holds up soil on his farm in Murang’a county, Kenya. (Photo: Robert Neptune/TNC)
Douglas Mungai holds up soil on his farm in Murang’a county, Kenya. (Photo: Robert Neptune/TNC)

Robust germplasm

How do we ensure that germplasm reserves are not potential vectors of pest and disease transmission? The second instalment in the CGIAR International Year of Plant Health Webinar Series tackles the often-overlooked issue of germplasm health.

A CIMMYT gene bank worker photographs maize accessions for the database for future reference. (Photo: Alfonso Cortés/CIMMYT)

Quality feed

By growing maize simultaneously for both human consumption and quality animal feed, farmers can get the most out of their crops and conserve natural resources like land and water.

A Bangladeshi farmer scoops up maize flour, produced from his own maize crop, as he prepares feed for his livestock. (Photo: S. Mojumder/CIMMYT)

Feeding communities

The traditional milpa intercrop — in which maize is grown together with beans, squash or other vegetable crops — can furnish a vital supply of food and nutrients for marginalized, resource-poor communities in the Americas.

A farmer holds a maize ear. (Photo: Cristian Reyna)
A farmer holds a maize ear. (Photo: Cristian Reyna)

A healthy planet

Compared to conventional tillage practices, sowing wheat directly into just-harvested rice fields without burning or removing straw or other residues can reduce severe air pollution while lessening irrigation needs.

Air pollution related to crop residue burning imposes enormous public health and economic burdens in northwestern India. (Photo: CIMMYT)
Burning crop residue pollutes the air in northeastern India. (Photo: CIMMYT)

Interested in learning more about CIMMYT’s health-related work? Check out our archive of health and nutrition content.

Featured image: A farmer inspects a drought-tolerant bean plant on a trial site in Malawi. (Photo: Neil Palmer/CIAT)

Field workers in Ethiopia weight the grain. (Photo: Hailemariam Ayalew/CIMMYT)

Revisiting the inverse size-productivity relationship

Written by Rodrigo Ordóñez on . Posted in News.

Field workers in Ethiopia weight the grain. (Photo: Hailemariam Ayalew/CIMMYT)
Field workers in Ethiopia weight the grain. (Photo: Hailemariam Ayalew/CIMMYT)

Quantifying agricultural productivity relies on measures of crop production and land area. Those measures need to be accurate, but it is often difficult to source reliable data. Inaccurate measurements affect our understanding of the relationship between agricultural productivity and land area.

Researchers examined the sensitivity of empirical assessments of this relationship to alternative measurement protocols. Scientists from the International Maize and Wheat Improvement Center (CIMMYT), Trinity College Dublin and the International Food Policy Research Institute (IFPRI) analyzed different methods of plot-level production and area measurement.

The study, to be published, is said to be the first to evaluate errors along the two dimensions —production and area — in all available measurement techniques.

Researchers found that errors from both production and area measurements explain the estimated inverse productivity-size relationship. When using a combination of the most accurate measures for yield and area — full plot harvest and total station — the inverse relationship vanishes. Consistent with previous studies, the study also shows that addressing one of the other sources of error — for example, either production or area estimates — does not eliminate the bias associated with measurement error.

For this study, the research team collected and used a unique dataset on maize production from Ethiopia, addressing measurement issues commonly found in other datasets that hinder accurate estimation of the size-productivity relationship. Specifically, the researchers considered six alternative land area measures: farmers’ self-reported estimates; estimates from low-cost old generation consumer-grade dedicated GPS receivers that have frequently been used in field data collection by research organizations over the past decade; estimates from single- and dual-frequency mobile phone GPS receivers; compass-and-rope estimates; and total station theodolite measurement.

An enumerator in Ethiopia measures grain moisture. (Photo: Hailemariam Ayalew/CIMMYT)
An enumerator in Ethiopia measures grain moisture. (Photo: Hailemariam Ayalew/CIMMYT)

Most cost-effective measurement methods

The study also provides a cost-effectiveness analysis of the different measurement methods. According to the researchers, the most expensive combination to use is full harvest yield with total station measurement. The cost is potentially prohibitively high for traditional surveys involving large samples.

It concludes that the optimal combination is crop-cut random quadrant measurements coupled with GPS measurement. This offers the best value for money of all the methods considered, since the results for the productivity-size regressions are like what is found when the gold-standard for yield and area measurement protocols are used.

Musa Hasani Mtambo and his family in their conservation agriculture plot in Hai, Tanzania. (Photo: Peter Lowe/CIMMYT)

Investment in maize for Africa pays off

Written by Rodrigo Ordóñez on . Posted in Press releases.

Musa Hasani Mtambo and his family in their conservation agriculture plot in Hai, Tanzania. (Photo: Peter Lowe/CIMMYT)
Musa Hasani Mtambo and his family in their conservation agriculture plot in Hai, Tanzania. (Photo: Peter Lowe/CIMMYT)

Between 1995-2015, nearly 60% of all maize varieties released in 18 African countries were CGIAR-related. At the end of this period, in 2015, almost half of the maize area in these countries grew CGIAR-related maize varieties. All that was accomplished through modest, maximum yearly investment of about $30 million, which showed high returns: in 2015, the aggregate yearly economic benefits for using CGIAR-related maize varieties released after 1994 were estimated to be between $660 million and $1.05 billion.

These are just some of the key findings of Impacts of CGIAR Maize Improvement in sub-Saharan Africa, 1995-2015 a new, comprehensive review of the two decades of longstanding, CGIAR-led work on improved maize for Africa.

A staple concern

Since its introduction to Africa in the 16th century, maize has become one of the most important food crops in the continent.

It accounts for almost a third of the calories consumed in sub-Saharan Africa. And it’s grown on over 38 million hectares in the region, mostly by rainfall-dependent smallholder farmers.

Climate change poses an existential threat to the millions who depend on the crop for their livelihood or for their next meal. Already 65% of the maize growing areas in sub-Saharan Africa face some level of drought stress.

Long-term commitment

Through the International Maize and Wheat Improvement Center (CIMMYT) and the International Institute of Tropical Agriculture (IITA), CGIAR has been working alongside countless regional partners since 1980s to develop and deploy climate-smart maize varieties in Africa.

This work builds on various investments including Drought-Tolerant Maize for Africa (DTMA) and Stress Tolerant Maize for Africa (STMA). Support for this game-changing work has generated massive impacts for smallholder farmers, maize consumers, and seed markets in the region. Throughout, the determination to strengthen the climate resilience of maize agri-food systems in Africa has remained the same.

To understand the impact of their work — and how to build on it in the coming years — researchers at CIMMYT and IITA took a deep dive into two decades’ worth of this work across 18 countries in sub-Saharan Africa. These findings add to our understanding of the impact of work that today benefits an estimated 8.6 million farmers in the region.

Big challenges remain. But with the right partnerships, know-how and resources we can have an outsize impact on meeting those challenges head on.

A researchers shows a maize leaf affected by fall armyworm at CIMMYT’s fall armyworm screenhouse in Kiboko, Kenya. (Photo: Jennifer Johnson/CIMMYT)

How do we sustainably manage transboundary diseases and crop pests?

Written by Madeline Dahm on . Posted in Features.

In our hyper-connected world, it should come as no surprise that recent years have shown a major uptick in the spread of transboundary pests and diseases. Integrated approaches have been effective in sustainably managing these border-jumping threats to farmers’ livelihoods and food security.

But a truly integrated approach accounts for not just the “cure,” but also how it can be sustainably incorporated into the agri-food system and social landscape.  For example, how do we know if the farmers who adopt disease- and pest-resistant seed will be able to derive better incomes? And how do we ensure that incentives are aligning with community norms and values to enable better adoption of integrated disease or pest management approaches?

Experts from across the CGIAR research system and its partners weighed in on this topic in the recent webinar on Integrated Pest and Disease Management, the third in the International Year of Plant Health Webinar series. Panelists shared valuable perspectives on the science of outbreaks, the social dimensions of crop pest and disease control, zoonotic disease risk, and how national, regional and global organizations can better coordinate their responses.

“The combination of science, global partnerships and knowledge helps all of us be better prepared to avoid the losses we’ve seen. . . Today, we’re going to see what this looks like in practice,” said Rob Bertram, chief scientist for the Bureau for Resilience and Food Security at USAID, and moderator of the event.

Participants on the webinar on Integrated Pest and Disease Management. (Photo: CIMMYT)
Participants on the webinar on Integrated Pest and Disease Management. (Photo: CIMMYT)

Understanding the sources

Wheat and maize, the key crops studied at the International Maize and Wheat Improvement Center (CIMMYT) are no stranger to destructive  diseases or pests, with fall armyworm, wheat blast, or maize lethal necrosis topping the list. But other staple crops and their respective economies are suffering as well — from infestations of cassava brown streak, potato cyst nematode, taro blight, desert locusts, and fusarium wilt, just to name a few.

What are the reasons for the expansion of these outbreaks? B.M. Prasanna, director of CIMMYT’s Global Maize Program explained that there are several: “Infected seed or planting material, vector movement, strong migratory capacity, contaminated field equipment, improper crop production commercialization practices, and global air and sea traffic” are all major causes.

Prevention and control of diseases and pests requires an integral strategy which mobilizes synergies of multiple institutions. (Graphic: B.M. Prasanna/CIMMYT)
Prevention and control of diseases and pests requires an integral strategy which mobilizes synergies of multiple institutions. (Graphic: B.M. Prasanna/CIMMYT)

Preventing outbreaks is always better than scrambling to find a cure, but as Prasanna pointed out, this requires a holistic, multi-institutional strategy including surveillance and early warning, quarantine and phytosanitary regulations, and technological solutions. Better access to monitoring and surveillance data, and sensitive, easy-to-use and affordable diagnostic equipment are essential, as is the proactive deployment of resistant crop varieties.

Building awareness about integrated disease and pest management is just as important, he told the attendees. “We must remember that IPM is not just Integrated Pest Management, but also ‘Integrating People’s Mindsets.’ That remains a major challenge. We need to think beyond our narrow disciplines and institutions and really come together to put IPM solutions into farmers’ fields,” Prasanna said.

Not all outbreaks are the same, but lessons can be shared

Regina Eddy, coordinator for the Fall Armyworm Interagency Task Force at USAID, works closely with the complex issue of scaling when it comes to disaster response and the roles of national, regional and global organizations.

“We need to develop inclusive partner stakeholder platforms, not designed ‘for them,’ but ‘with them,’” said Eddy. “We cannot tackle food security issues alone. Full stop.”

Closing the gap between social and biophysical science

Nozomi Kawarazuka, social anthropologist at the International Potato Center (CIP) explained how researchers can improve the uptake of their new seed, innovation, or agronomic practice by involving social scientists to understand the gender norms and social landscape at the beginning of the project — in the initial assessment phase.

Kawarazuka highlighted how involving women experts and extension workers in sectors that are typically male-dominated helps reduce bias and works towards changing perceptions.

“In South Asia, women farmers hesitate to engage with male government extension workers,” she said. “Women experts and extension workers reduce this barrier. Gender and social diversity in the plant health sector is an entry point to develop innovations that are acceptable to women as well as men and helps scale up adoption of innovations in the community.

Gender and social dimensions of pest and disease control: a call for collaboration (Graphic: Nozomi Kawarazuka/CIP)
Gender and social dimensions of pest and disease control: a call for collaboration (Graphic: Nozomi Kawarazuka/CIP)

The world is watching agriculture and livestock

Zoonotic diseases, or zoonoses, are caused by pathogens spread between animals and people. Understanding zoonotic disease risk is an essential and timely topic in the discussion of integrated pest management. Poor livestock management practices, lack of general knowledge on diseases and unsafe yet common food handling practices put populations at risk.

“It’s especially timely, [to have this] zoonosis discussion in our COVID-plagued planet. The whole world is going to be looking to the food and agricultural sectors to do better,” Bertram said.

Annet Mulema, a gender and social scientist at the International Livestock Research Institute (ILRI) described results of a study showing how community conversations transformed gender relations and zoonotic disease risk in rural Ethiopia, where 80% of the population depends on agriculture and has direct contact with livestock.

“There were noticeable changes in attitude and practices among men and women regarding unsafe handling of animals and consumption of animal-source foods,” Mulema explained. “Community conversations give men and women involved a voice, it allows for a variety of ideas to be expressed and discussed, leads to community ownership of conclusions and action plans, and opens communication channels among local service providers and community members.”

Proportion of women and men practicing safe handling of livestock and animal source foods, before and after community conversation intervention. (Graphic: Annet Mulema/ILRI)
Proportion of women and men practicing safe handling of livestock and animal source foods, before and after community conversation intervention. (Graphic: Annet Mulema/ILRI)

Local to global, and global to local

Panelists agreed that improving capacity is the most powerful lever to advance approaches for integrated pest management and plant health, while connected and inclusive partnerships along the value chain make the whole system more resilient. The amount of scientific knowledge on ways to combat plant pests and diseases is increasing, and we have new tools to connect the global with the local and bring this knowledge to the community level.

The fourth and final CGIAR webinar on plant health is scheduled for March 31 and will focus on a the intersectional health of people, animals, plants and their environments in a “One Health” approach.

Farmers at a demonstration farm field day organized by East African Seed Company. (Photo: Courtesy)

Fighting the stress

Written by Rodrigo Ordóñez on . Posted in Features.

East African Seed Company has a rich history of nearly 50 years, serving farmers with improved climate-resilient seed varieties. Established in 1972, the company produces and sells improved seed, through a wide distribution network in at least 15 countries in sub-Saharan Africa. It also markets agrochemicals and other farm inputs, and has ambitions of expanding to the rest of Africa, trading as Agriscope Africa Limited.

Smallholder farmers in sub-Saharan Africa continue to face multiple biotic and abiotic stresses as they try to improve their farms’ productivity and their livelihoods. Maize seed that guarantees high yield is a key trait, coupled with other key attributes such as drought tolerance, disease and pest resistance, early seedling vigor as well as suitability for food and animal feed.

With the varieties serving both small- and large-scale commercial farmers, challenges such as the fall armyworm, diminishing soil fertility and erratic rains have persisted in recent years and remain as key farming obstacles. “Such challenges diminish crop production and the grain quality thereby, lessening farmers’ profitability,” says Rogers Mugambi, Chief Operating Officer of East African Seed Company.

Scientists at the International Maize and Wheat Improvement Center (CIMMYT), in collaboration with partners in the national agriculture research systems and the commercial seed sector, continue to develop seed varieties that can guarantee decent yield even in times of climatic, disease and pest stress.

General view of the East African Seed warehouse. (Photo: Jerome Bossuet/CIMMYT)
General view of the East African Seed warehouse. (Photo: Jerome Bossuet/CIMMYT)

Top-notch research trickles down to farmers

Over the years, East African Seed has inked partnerships with CIMMYT, national research institutes and other agencies in the countries where it operates. Such partnerships have been the driving force to its success and the impacts within the farming communities in sub-Saharan Africa.

“Our collaboration with CIMMYT began in 2008 with germplasm acquisition. The cooperation has expanded to include testing networks for new hybrids, early-generation seed production and marketing. The overall beneficiary is the smallholder farmer who can access quality seeds and produce more with climate-smart products,” Mugambi says.

Apart from the multi-stress-tolerant varieties developed and released over time by the national agricultural research programs, CIMMYT recently announced a breakthrough: fall armyworm-tolerant elite maize hybrids for eastern and southern Africa. This success followed three years of rigorous research and experiments conducted in Kenya and signified a key milestone in the fight against fall armyworm.

As part of the partnership in the Drought Tolerant Maize for Africa (DTMA) and Stress Tolerant Maize for Africa (STMA) projects, East African Seed Company (Agriscope Africa Limited) established demonstration farms and conducted field days in Kenya, reaching thousands of farmers as a result. It was also able to produce early generation seed, which supported production of 2,000 metric tons of certified seed. This partnership now continues in the Accelerating Genetic Gains in Maize and Wheat (AGG) project.

The company has contracted large- and small-scale growers across the country to meet its seed production targets.

“Most of our small-scale growers are clustered in groups of up to 30 farmers with less than five acres of farmland. The large growers have advanced irrigation facilities such as the pivot system and seed processing plants. The seed from the fields is pre-cleaned and dried in the out-grower facilities before delivery to our factory for further cleaning and processing,” Mugambi explains.

A handful of improved maize seed from the drought-tolerant variety TAN 250, developed and registered for sale in Tanzania through CIMMYT's Drought Tolerant Maize for Africa (DTMA) project. (Photo: Anne Wangalachi/CIMMYT)
A handful of improved maize seed from the drought-tolerant variety TAN 250, developed and registered for sale in Tanzania through CIMMYT’s Drought Tolerant Maize for Africa (DTMA) project. (Photo: Anne Wangalachi/CIMMYT)

Out with the drought

Currently, of the 1,300 metric tons of drought-tolerant hybrid seeds it produces yearly, 500 metric tons constitute those derived from the partnership in the STMA project. Two notable hybrids,  HODARI (MH501) and TOSHEKA (MH401), were derived during the DTMA and STMA projects. Released in 2014 and accepted for regional certification through the Common Market for Eastern and Southern Africa (COMESA)’s regional catalogue, the MH501 is a mid-altitude adapted and medium maturing three-way cross hybrid. The yield advantage of 15% over the local commercial checks triggered widespread adoption by the farmers, according to Mugambi. In Kenya, it was used as a commercial check during national performance trials, from 2017 to 2019.

The MH401, an early maturing hybrid with moderate drought tolerance, has been adopted in lowland and mid-altitude dry ecologies of Kenya and Tanzania. It has a 20% yield advantage over the local commercial checks.

As part of its varietal replacement, East African Seed Company looks to steadily retire older varieties such as KH600-15A and WE1101 and promote new ones including TAJIRI (EASH1220), TAJI (MH502) and FARAJA (MH503).

To promote new varieties and successfully reach smallholders, the company conducts field days, farm-level varietal demonstrations, road shows and radio programs. It also disseminates information on the benefits of new varieties while also dispensing promotional materials such as branded t-shirts and caps.

“Additionally, we organize annual field days at our research farm in Thika, where key and influential farmers and other stakeholders are invited from across Kenya and neighboring countries to learn about our new agricultural technologies,” Mugambi says.

What is nixtamalization?

Written by Emma Orchardson on . Posted in Explainers.

For centuries, people across Mexico and Central America have been using a traditional method, known as nixtamalization, to process their maize.

Now carried out both at household and industrial levels, this technique offers a range of nutritional and processing benefits. It could easily be adopted by farmers and consumers in other parts of the world.

What is nixtamalization?

Nixtamalization is a traditional maize preparation process in which dried kernels are cooked and steeped in an alkaline solution, usually water and food-grade lime (calcium hydroxide).

After that, the maize is drained and rinsed to remove the outer kernel cover (pericarp) and milled to produce dough that forms the base of numerous food products, including tortillas and tamales.

How does it work?

Key steps of the traditional nixtamalization process. (Graphic: Nancy Valtierra/CIMMYT)
Key steps of the traditional nixtamalization process. (Graphic: Nancy Valtierra/CIMMYT)

What happens when maize kernels are nixtamalized?

The cooking (heat treatment) and steeping in the alkaline solution induce changes in the kernel structure, chemical composition, functional properties and nutritional value.

For example, the removal of the pericarp leads to a reduction in soluble fiber, while the lime cooking process leads to an increase in calcium content. The process also leads to partial starch gelatinization, partial protein denaturation — in which proteins present in the kernel become insoluble — and a partial decrease in phytic acid.

What are the benefits of processing maize in this way?

In addition to altering the smell, flavor and color of maize products, nixtamalization provides several nutritional benefits including:

  • Increased bioavailability of vitamin B3 niacin, which reduces the risk of pellagra disease
  • Increased calcium intake, due to its absorption by the kernels during the steeping process
  • Increased resistant starch content in food products, which serves as a source of dietary fiber
  • Significantly reduced presence of mycotoxins such as fumonisins and aflatoxins
  • Increased bioavailability of iron, which decreases the risk of anemia

These nutritional and health benefits are especially important in areas where maize is the dietary staple and the risk of aflatoxins is high, as removal of the pericarp is thought to help reduce aflatoxin contamination levels in maize kernels by up to 60% when a load is not highly contaminated.

Additionally, nixtamalization helps to control microbiological activity and thus increases the shelf life of processed maize food products, which generates income and market opportunities for agricultural communities in non-industrialized areas.

Where did the practice originate?

The word itself comes from the Aztec language Nahuatl, in which the word nextli means ashes and tamali means unformed maize dough.

Populations in Mexico and Central America have used this traditional maize processing method for centuries. Although heat treatments and soaking periods may vary between communities, the overall process remains largely unchanged.

Today nixtamalized flour is also produced industrially and it is estimated that more than 300 food products commonly consumed in Mexico alone are derived from nixtamalized maize.

Can farmers and consumers in other regions benefit from nixtamalization?

Nixtamalization can certainly be adapted and adopted by all consumers of maize, bringing nutritional benefits particularly to those living in areas with low dietary diversity.

Additionally, the partial removal of the pericarp can contribute to reduced intake of mycotoxins. Aflatoxin contamination is a problem in maize producing regions across the world, with countries as diverse as China, Guatemala and Kenya all suffering heavy maize production losses as a result. While training farmers in grain drying and storage techniques has a significant impact on reducing post-harvest losses, nixtamalization technology could also have the potential to prevent toxin contamination and significantly increase food safety when used appropriately.

If adapted, modern nixtamalization technology could also help increase the diversity of uses for maize in food products that combine other food sources like vegetables.

Cover photo: Guatemalan corn tortillas. (Photo: Marco Verch, CC BY 2.0 DE)

Development of Smart Innovation through Research in Agriculture (DeSIRA)

Written by Emma Orchardson on . Posted in Uncategorized.

The overall objective of the 5-year EU-funded DeSIRA action, led by the International Potato Center (CIP), is to improve climate change adaptation of agricultural and food systems in Malawi through research and uptake of integrated technological innovations.

CIMMYT’s role is focused on the following project outputs:

  • Identify and develop integrated technology options that effectively provide management options to contribute to reducing risks and increasing resilience and productivity of the smallholder farmers’ agrifood systems in Malawi. Towards this objective, CIMMYT will evaluate drought-tolerant and nutritious maize varieties under conservation agriculture and conventional practices, and assess the overall productivity gains from agronomic and germplasm improvements versus current farming practices.
  • Develop, test and promote robust integrated pest and disease management strategies to predict, monitor and control existing and emerging biotic threats to agriculture while minimizing risks to farmers’ health and damage to the environment. Towards this objective, CIMMYT will evaluate the effect of striga on maize performance under conservation agriculture and conventional practices; evaluate farmer methods and other alternatives to chemical sprays for the control of fall armyworm; and study the effect of time of planting for controlling fall armyworm.