When one thinks of heat waves, the natural tendency is to consider high daytime temperatures. However, when most people are sleeping, a hidden factor of climate change is taking place: temperatures at night are not dipping as much as observed in the past, which has dramatic effects on many crops, including wheat. In fact, nocturnal temperatures are rising more rapidly globally than daytime temperatures, which is of great concern as research is starting to show the sensitivity of plants to warmer nights.
A group of researchers, from the University of Nottingham, the Sonora Institute of Technology (ITSON) and CIMMYT examined how different wheat lines reacted to the effects of rising nighttime temperatures treatments imposed in the field, for three years at CIMMYT’s Norman E. Borlaug experimental station in Ciudad Obregon, Mexico. Their results, Night-time warming in the field reduces nocturnal stomatal conductance and grain yield but does not alter daytime physiological responses were published in New Phytologist.
Previous studies revealed that wheat yields decline 3-8% for every 1°C increase of the nighttime low temperature. For this research, the team subjected the selected wheat breeds to an increase of 2°C. The varieties were selected based on previous evaluations of their daytime heat tolerance.
Notably, the findings highlighted that genotypes classified as traditionally heat tolerant were sensitive to small increases in nighttime temperature even without daytime temperature stress, implying that adaptation to warm nights is likely under independent genetic control than daytime adaptation.
“These results are exciting as they offer new perspectives on the impact of night temperatures on diurnal photosynthetic performance and wheat yields,” said co-first author Liana Acevedo-Siaca. “Through this work we found that wheat yields decreased, on average, 1.9% for every degree that increased at night. Our hope is that this work can help inform future breeding and research decisions to work towards more resilient agricultural systems, capable of dealing with warmer day and nighttime temperatures.”
Plants at night
While plants do not “sleep” in the way animals do, nighttime for plants has long been thought of as a time of repose compared to daylight hours when photosynthesis is taking place. However, recent findings have revealed that plants are more active than previously thought at night, for example in transpiration, which is the process of plants gathering liquid water from the soil and releasing water vapor through their leaves.
“An interesting result of our research was that we found varieties characterized as heat tolerant, showed some of the greatest declines in yield in response to warmer nights,” said co-first author Lorna McAusland, Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham. “These are the varieties wheat farmers are being recommended for increasing daytime temperature, and so there is a worry that advantages gained during the day are being lost at night.”
“There is likely a goldmine of opportunities related to genetically improving nighttime processes in crops, as very little research has been conducted in that space. Useful genetic variation can be expected, since ‘night’ traits have never been considered or needed before now,” said co-author Matthew Reynolds, who leads the CIMMYT’s Wheat Physiology Lab that collaborates globally with experts via HeDWIC (https://hedwic.org/) and uses physiological pre-breeding as a conduit for cutting edge technologies to impact mainstream breeding.
Workshop participants stand for a group photo. (Photo: Danny Ward/John Innes Centre)
On April 26–29, 2022, researchers from Nepal participated in a workshop on the use of MARPLE Diagnostics, the most advanced genetic testing methodology for strain-level diagnostics of the deadly wheat yellow rust fungus. Scientists from the International Maize and Wheat Improvement Center (CIMMYT) and the John Innes Centre trained 21 researchers from the Nepal Agricultural Research Council (NARC) and one from iDE. The workshop took place at NARC’s National Plant Pathology Research Centre in Khumaltar, outside the capital Kathmandu.
“The need for new diagnostic technologies like MARPLE and the critical timing of the workshop was highlighted by the severe yellow rust outbreak observed this season in the western areas of Nepal,” commented Dave Hodson, Senior Scientist at CIMMYT and project co-lead. “Having national capacity to detect the increasing threats from yellow rust using MARPLE will be an important tool to help combat wheat rusts in Nepal”.
The yellow rust fungus can cause grain yield losses of 30–80 % to wheat, Nepal’s third most important food crop.
Current diagnostic methods for wheat rust used in Nepal are slow, typically taking months between collecting the sample and final strain identification. They are also costly and reliant on sending samples overseas to highly specialized labs for analysis.
MARPLE (Mobile and Real-time PLant disEase) Diagnostics is the first method to place strain-level genetic diagnostics capability directly into the hands of Nepali researchers, generating data in-country in near-real time, for immediate integration into early warning systems and disease management decisions.
“This is a fantastic opportunity to bring the latest innovations in plant disease diagnostics for the wheat rust pathogens to where they are needed most, in the hands of researchers in the field working tirelessly to combat these devastating diseases,” commented Diane Saunders, Group Leader at the John Innes Centre and project co-lead.
Diane Saunders (left), Group Leader at the John Innes Centre and project co-lead, observes workshop participants during the use of MARPLE. (Photo: Danny Ward/John Innes Centre)
Suraj Baidya senior scientist and chief of the National Plant Pathology Research Centre at NARC noted the worrying recent geographical expansion of yellow rust in Nepal. “Due to global warming, yellow rust has now moved into the plain and river basin area likely due to evolution of heat tolerant pathotypes. MARPLE Diagnostics now gives us the rapid diagnostics needed to help identify and manage these changes in the rust pathogen population diversity,” he said.
The highly innovative MARPLE Diagnostics approach uses the hand-held MinION nanopore sequencer, built by Oxford Nanopore, to generate genetic data to type strains of the yellow rust fungus directly from field samples.
Beyond MARPLE Diagnostics, Saunders noted that “the workshop has also opened up exciting new possibilities for researchers in Nepal, by providing local genome-sequencing capacity that is currently absent.”
MARPLE (Mobile and Real-time PLant disEase) Diagnostics is a revolutionary mobile lab kit. It uses nanopore sequence technology to rapidly diagnose and monitor wheat rust in farmers’ fields. (Photo: Danny Ward/John Innes Centre)
What’s next for MARPLE Diagnostics in Nepal?
Following the successful workshop, Nepali researchers will be supported by CIMMYT and the John Innes Centre to undertake MARPLE Diagnostics on field samples collected by NARC. “The current plan includes monitoring of yellow rust on the summer wheat crop planted at high hill areas and then early sampling in the 2022/23 wheat season,” Hodson noted.
“We were struck by the enthusiasm and dedication of our colleagues to embrace the potential offered by MARPLE Diagnostics. Looking forward, we are excited to continue working with our Nepali colleagues towards our united goal of embedding this methodology in their national surveillance program for wheat rusts,” Saunders remarked.
MARPLE Diagnostics is supported by the Feed the Future Innovation Lab for Current and Emerging Threats to Crops, funded by the United States Agency for International Development (USAID), the UK Biotechnology and Biological Sciences Research Council (BBSRC) Innovator of the Year Award, the CGIAR Big Data Platform Inspire Challenge, the Bill & Melinda Gates Foundation and the United Kingdom’s Foreign, Commonwealth and Development Office.
With the past decade identified as the warmest on record and global temperatures predicted to rise by as much as 2 degrees Celsius over preindustrial levels by 2050, the world’s staple food crops are increasingly under threat.
A new review published this month in the Journal of Experimental Botany describes how researchers from the International Maize and Wheat Improvement Center (CIMMYT) and collaborators are boosting climate resilience in wheat using powerful remote sensing tools, genomics and big data analysis. Scientists are combining multiple approaches to explore untapped diversity among wheat genetic resources and help select better parents and progeny in breeding.
The review — authored by a team of 25 scientists from CIMMYT, Henan Agricultural University, the University of Adelaide and the Wheat Initiative — also outlines how this research can be harnessed on a global level to further accelerate climate resilience in staple crops.
“An advantage of understanding abiotic stress at the level of plant physiology is that many of the same tools and methods can be applied across a range of crops that face similar problems,” said first author and CIMMYT wheat physiologist Matthew Reynolds.
Abiotic stresses such as temperature extremes and drought can have devastating impacts on plant growth and yields, posing a massive risk to food security.
Harnessing research across a global wheat improvement network for climate resilience: research gaps, interactive goals, and outcomes.
Addressing research gaps
The authors identified nine key research gaps in efforts to boost climate resilience in wheat, including limited genetic diversity for climate resilience, a need for smarter strategies for stacking traits and addressing the bottleneck between basic plant research and its application in breeding.
Based on a combination of the latest research advances and tried-and-tested breeding methods, the scientists are developing strategies to address these gaps. These include:
Using big data analysis to better understand stress profiles in target environments and design wheat lines with appropriate heat and drought adaptive traits.
Exploring wheat genetic resources for discovery of novel traits and genes and their use in breeding.
Accelerating genetic gains through selection techniques that combine phenomics with genomics.
Crowd-sourcing new ideas and technologies from academia and testing them in real-life breeding situations.
These strategies will be thoroughly tested at the Heat and Drought Wheat Improvement Network (HeDWIC) Hub under realistic breeding conditions and then disseminated to other wheat breeding programs around the world facing similar challenges.
One factor that strongly influences the success and acceleration of climate resilience technologies, according to Reynolds, is the gap between theoretical discovery research and crop improvement in the field.
“Many great ideas on how to improve climate-resilience of crops pile up in the literature, but often remain ‘on the shelf’ because the research space between theory and practice falls between the radar of academia on the one hand, and that of plant breeders on the other,” Reynolds explained.
Translational research — efforts to convert basic research knowledge about plants into practical applications in crop improvement — represents a necessary link between the world of fundamental discovery and farmers’ fields and aims to bridge this gap.
Main research steps involved in translating promising technologies into genetic gains (graphical abstract, adapted from Reynolds and Langridge, 2016). Reprinted under licence CC BY-NC-ND.
The impacts of this research, conducted under HeDWIC — a project led by CIMMYT in partnership with experts around the world — will be validated on a global scale through the International Wheat Improvement Network (IWIN), with the potential to reach at least half of the world’s wheat-growing area.
The results will benefit breeders and researchers but, most importantly, farmers and consumers around the world who rely on wheat for their livelihoods and their diets. Wheat accounts for about 20% of all human calories and protein, making it a pillar of food security. For about 1.5 billion resource-poor people, wheat is their main daily staple food.
With the world population projected to rise to almost ten billion by 2050, demand for food is predicted to increase with it. This is especially so for wheat, being a versatile crop both in terms of where it can grow and its many culinary and industrial uses. However, current wheat yield gains will not meet 2050 demand unless serious action is taken. Translational research and strategic breeding are crucial elements in ensuring that research is translated into higher and stable yields to meet these challenges.
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 Obregón, 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
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 Obregón, 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)
CIMMYT researchers use coverings to increase night-time temperatures and study wheat’s heat tolerance mechanisms, key to overcoming climate change challenges to wheat production. (Photo: Kevin Pixley/CIMMYT)
The International Maize and Wheat Improvement Center (CIMMYT) and the John Innes Centre (JIC) have announced a strategic collaboration for joint research, knowledge sharing and communications, to further the global effort to develop the future of wheat.
Wheat, a cornerstone of the human diet that provides 20% of all calories and protein consumed worldwide, is threatened by climate change-related drought and heat, as well as increased frequency and spread of pest and disease outbreaks. The new collaboration, building on a history of successful joint research achievements, aims to harness state-of-the-art technology to find solutions for the world’s wheat farmers and consumers.
“I am pleased to formalize our longstanding partnership in wheat research with this agreement,” said CIMMYT Deputy Director General for Research Kevin Pixley. “Our combined scientific strengths will enhance our impacts on farmers and consumers, and ultimately contribute to global outcomes, such as the Sustainable Development Goal of Zero Hunger.”
Director of the John Innes Centre, Professor Dale Sanders commented, “Recognizing and formalizing this long-standing partnership will enable researchers from both institutes to focus on the future, where the sustainable development of resilient crops will benefit a great many people around the world.”
Thematic areas for collaboration
Scientists from CIMMYT and JIC will work jointly to apply cutting-edge approaches to wheat improvement, including:
developing and deploying new molecular markers for yield, resilience and nutritional traits in wheat to facilitate deploying genomic breeding approaches using data on the plant’s genetic makeup to improve breeding speed and accuracy;
generating, sharing and exploiting the diversity of wheat genetic material produced during crossing and identified in seed banks;
pursuing new technologies and approaches that increase breeding efficiency to introduce improved traits into new wheat varieties; and
developing improved technologies for rapid disease diagnostics and surveillance.
Plans for future collaborations include establishing a new laboratory in Norwich, United Kingdom, as part of the Health Plants, Healthy People, Healthy Plant (HP3) initiative.
Bringing innovations to farmers
An important goal of the collaboration between CIMMYT and JIC is to expand the impact of the joint research breakthroughs through knowledge sharing and capacity development. Stakeholder-targeted communications will help expand the reach and impact of these activities.
“A key element of this collaboration will be deploying our innovations to geographically diverse regions and key CIMMYT partner countries that rely on smallholder wheat production for their food security and livelihoods,” said CIMMYT Global Wheat Program Director Alison Bentley.
Capacity development and training will include collaborative research projects, staff and student exchanges and co-supervision of graduate students, exchange of materials and data, joint capacity building programs, and shared connections to the private sector. For example, plans are underway for a wheat improvement summer school for breeders in sub-Saharan African countries and an internship program to work on the Mobile And Real-time PLant disease (MARPLE) portable rust testing project in Ethiopia.
INTERVIEW OPPORTUNITIES:
Alison Bentley – Director, Global Wheat Program, International Maize and Wheat Improvement Center (CIMMYT)
Dale Sanders – Director, John Innes Centre
OR MORE INFORMATION, OR TO ARRANGE INTERVIEWS, CONTACT THE MEDIA TEAM:
The International Maize and Wheat Improvement Center (CIMMYT) is the global leader in publicly-funded maize and wheat research and related farming systems. Headquartered near Mexico City, CIMMYT works with hundreds of partners throughout the developing world to sustainably increase the productivity of maize and wheat cropping systems, thus improving global food security and reducing poverty. CIMMYT is a member of the CGIAR System and leads the CGIAR Research Programs on Maize and Wheat and the Excellence in Breeding Platform. The Center receives support from national governments, foundations, development banks and other public and private agencies. For more information, visit staging.cimmyt.org.
ABOUT THE JOHN INNES CENTRE:
The John Innes Centre is an independent, international centre of excellence in plant science, genetics and microbiology. Our mission is to generate knowledge of plants and microbes through innovative research, to train scientists for the future, to apply our knowledge of nature’s diversity to benefit agriculture, the environment, human health, and wellbeing, and engage with policy makers and the public.
We foster a creative, curiosity-driven approach to fundamental questions in bio-science, with a view to translating that into societal benefits. Over the last 100 years, we have achieved a range of fundamental breakthroughs, resulting in major societal impacts. Our new vision Healthy Plants, Healthy People, Healthy Planet (www.hp3) is a collaborative call to action. Bringing knowledge, skills and innovation together to create a world where we can sustainably feed a growing population, mitigate the effects of climate change and use our understanding of plants and microbes to develop foods and discover compounds to improve public health.
The proportion of children under five years old who are stunted in Zimbabwe is estimated to be 28%. Stunting leads to a higher risk of dying, poorer school performance and lower wages in adult life. Improving the quantity and quality of food for children under two years of age is the best approach we have to prevent stunting. An earlier project (Sanitation, Hygiene, Infant Nutrition Efficacy, SHINE) provided mothers with information on infant and young child feeding (IYCF) and provided a daily supplement (Nutributter) to provide extra calories and vitamins to children. However, many children still did not meet their daily nutrient requirements and over one-quarter remained stunted.
The SHINE data showed that nutrient intake remained insufficient to meet both macro- and micronutrient requirements for most children. The overarching hypothesis of the CHAIN project is that this nutrient gap can be filled by a combined agriculture and infant-feeding intervention.
Objectives:
Deliver an integrated agriculture and infant feeding intervention (“IYCF-plus”) to households in a randomized, community-based trial in rural Zimbabwe
Evaluate the impact of IYCF-plus on nutrient intake and growth in young children at risk of stunting
Evaluate the impact of the IYCF-plus intervention on biological barriers to nutrient uptake and utilization
Identify metabolic signatures of the IYCF-plus intervention in young children
The “double burden of malnutrition” refers to the seemingly paradoxical coexistence of obesity and undernutrition. It affects people whose diet consists primarily of “empty” calories: high-energy foods lacking in essential vitamins and minerals.
This project takes aim at both issues by combining improved agronomic practices with the use of biofortified maize varieties, to increase the nutritional value of maize, Zimbabwe’s most important, high-calorie staple food crop.
This project, whose full title is “Addressing malnutrition with biofortified maize in Zimbabwe: From crop management to policy and consumers”, will carry out on-station trials at Harare Research Station and Domboshava Training Centre, and conduct on-farm trials with 60 farmers in two wards in Murehwa district. These trials will help researchers predict the effect of bio + agro fortification at the national level. Project findings will be broadly disseminated through a well-defined stakeholder engagement strategy.
Objectives:
Evaluate new Provitamin A maize varieties and the next generation of multiple-biofortified lines under different agronomic practices to gain knowledge on the combination of bio + agronomic fortification.
Determine the actual nutrient content of the new Provitamin A lines in farmers’ fields with a range of different soil fertility levels and under farmers crop management.
Evaluate the possible impact of the combined bio + agro fortification approach on micronutrient uptake and human health by integrating the new grain composition with food supply data from household/individual dietary surveys at country level in Zimbabwe.
To move knowledge into practice, the information developed throughout the project will be distributed to stakeholders working in nutrition in Zimbabwe. This will ensure that the knowledge generated in the project helps farmers and consumers to maximize the benefits from biofortified crops.
Most small farmers in sub-Saharan Africa rely on rain-fed agriculture to sufficiently feed their families. However, they are increasingly confronted with climate-induced challenges which hinder crop production and yields.
In recent years, evidence of variable rainfall patterns, higher temperatures, depleted soil quality and infestations of destructive pests like fall armyworm cause imbalances in the wider ecosystem and present a bleak outlook for farmers.
Addressing these diverse challenges requires a unique skill set that is found in the role of systems agronomist.
Isaiah Nyagumbo joined the International Maize and Wheat Improvement Center (CIMMYT) in 2010 as a Cropping Systems Agronomist. Working with the Sustainable Intensification program, Nyagumbo has committed his efforts to developing conservation agriculture technologies for small farming systems.
“A unique characteristic of systems agronomists,” Nyagumbo explains, “is the need to holistically understand and address the diverse challenges faced by farming households, and their agro-ecological and socio-economic environment. They need to have a decent understanding of the facets that make technology development happen on the ground.”
“This understanding, combined with technical and agronomical skills, allows systems agronomists to innovate around increasing productivity, profitability and efficient farming practices, and to strengthen farmers’ capacity to adapt to evolving challenges, in particular those related to climate change and variability,” Nyagumbo says.
Isaiah Nyagumbo stands next to a field of maize and pigeon pea. Currently, Nyagumbo’s research seeks to better understand the resilience benefits of cereal-legume cropping systems and how different planting configurations can help to improve system productivity. (Photo: CIMMYT)
Gaining expert knowledge
Raised by parents who doubled as teachers and small-scale commercial farmers, Nyagumbo was exposed to the realities of producing crops for food and income while assisting with farming activities at his rural home in Dowa, Rusape, northeastern Zimbabwe. This experience shaped his decision to study for a bachelor’s degree in agriculture specializing in soil science at the University of Zimbabwe and later a master’s degree in soil and water engineering at Silsoe College, Cranfield University, United Kingdom.
Between 1989 and 1994, Nyagumbo worked with public and private sector companies in Zimbabwe researching how to develop conservation tillage systems in the smallholder farming sector, which at the time focused on reducing soil erosion-induced land degradation.
Through participatory technology development and learning, Nyagumbo developed a passion for closely interacting with smallholder farmers from Zimbabwe’s communal areas as it dawned to him that top-down technology transfer approaches had their limits when it comes to scaling technologies. He proceeded to study for his PhD in 1995, focusing on water conservation and groundwater recharge under different tillage technologies.
Upon completion of his PhD, Nyagumbo started lecturing at the University of Zimbabwe in 2001, at the Department of Soil Science and Agricultural Engineering, a route that opened collaborative opportunities with key international partners including CIMMYT.
“This is how I began my engagements with CIMMYT, as a collaborator and jointly implementing on-farm trials on conservation agriculture and later broadening the scope towards climate-smart agriculture technologies,” Nyagumbo recalls.
By the time an opportunity arose to join CIMMYT in 2010, Nyagumbo realized that “it was the right organization for me, moving forward the agenda of sustainability and focusing on improving productivity of smallholder farmers.”
Climate-smart results
Cropping systems agronomist Isaiah Nyagumbo inspects a maize ear at the Chimbadzwa plot in Ward 4, Murewa, Zimbabwe. (Photo: CIMMYT)
Projects such as SIMLESA show results of intensification practices and climate-smart technologies aimed at improving smallholder farming systems in eastern and southern Africa.
“One study showed that when conservation agriculture principles such as minimum tillage, rotation, mulching and intercropping are applied, yield increases ranging from 30-50 percent can be achieved,” Nyagumbo says.
Another recent publication demonstrated that the maize yield superiority of conservation agriculture systems was highest under low-rainfall conditions while high-rainfall conditions depressed these yield advantages.
Furthermore, studies spanning across eastern and southern Africa also showed how drainage characteristics of soils affect the performance of conservation agriculture technologies. “If we have soils that are poorly drained, the yield difference between conventional farming practices and conservation agriculture tends to be depressed, but if the soils are well drained, higher margins of the performance of conservation agriculture are witnessed,” he says.
Currently, Nyagumbo’s research efforts in various countries in eastern and southern Africa seek to better understand the resilience benefits of cereal-legume cropping systems and how different planting configurations can help to improve system productivity.
“Right now, I am focused on understanding better the ‘climate-smartness’ of sustainable intensification technologies.”
In Malawi, Nyagumbo is part of a team evaluating the usefulness of different agronomic practices and indigenous methods to control fall armyworm in maize-based systems. Fall armyworm has been a troublesome pest particularly for maize in the last four or five seasons in eastern and southern Africa, and finding cost effective solutions is important for farmers in the region.
Future efforts are set to focus further on crop-livestock integration and will investigate how newly developed nutrient-dense maize varieties can contribute to improved feed for livestock in arid and semi-arid regions in Zimbabwe.
Sharing results
Another important aspiration for Nyagumbo is the generation of publications to share the emerging results and experiences gained from his research with partners and the public. Working in collaboration with others, Nyagumbo has published more than 30 articles based on extensive research work.
“Through the data sharing policy promoted by CIMMYT, we have so much data generated across the five SIMLESA project countries which is now available to the public who can download and use it,” Nyagumbo says.
While experiences with COVID-19 have shifted working conditions and restricted travel, Nyagumbo believes “through the use of virtual platforms and ICTs we can still achieve a lot and keep in touch with our partners and farmers in the region.”
Overall, he is interested in impact. “The greatest reward for me is seeing happy and transformed farmers on the ground, and knowing my role is making a difference in farmers’ livelihoods.”
Researchers working on the Seeds of Discovery (SeeD) initiative, which aims to facilitate the effective use of genetic diversity of maize and wheat, have genetically characterized 79,191 samples of wheat from the germplasm banks of the International Maize and Wheat Improvement Center (CIMMYT) and the International Center for Agricultural Research in the Dry Areas (ICARDA).
A new study analyzing the diversity of almost 80,000 wheat accessions reveals consequences and opportunities of selection footprints. (Photo: Keith Ewing)
Researchers working on the Seeds of Discovery (SeeD) initiative, which aims to facilitate the effective use of genetic diversity of maize and wheat, have genetically characterized 79,191 samples of wheat from the germplasm banks of the International Maize and Wheat Improvement Center (CIMMYT) and the International Center for Agricultural Research in the Dry Areas (ICARDA).
The findings of the study published today in Nature Communications are described as “a massive-scale genotyping and diversity analysis” of the two types of wheat grown globally — bread and pasta wheat — and of 27 known wild species.
Wheat is the most widely grown crop globally, with an annual production exceeding 600 million tons. Approximately 95% of the grain produced corresponds to bread wheat and the remaining 5% to durum or pasta wheat.
The main objective of the study was to characterize the genetic diversity of CIMMYT and ICARDA’s internationally available collections, which are considered the largest in the world. The researchers aimed to understand this diversity by mapping genetic variants to identify useful genes for wheat breeding.
From germplasm bank to breadbasket
The results show distinct biological groupings within bread wheats and suggest that a large proportion of the genetic diversity present in landraces has not been used to develop new high-yielding, resilient and nutritious varieties.
“The analysis of the bread wheat accessions reveals that relatively little of the diversity available in the landraces has been used in modern breeding, and this offers an opportunity to find untapped valuable variation for the development of new varieties from these landraces”, said Carolina Sansaloni, high-throughput genotyping and sequencing specialist at CIMMYT, who led the research team.
The study also found that the genetic diversity of pasta wheat is better represented in the modern varieties, with the exception of a subgroup of samples from Ethiopia.
The researchers mapped the genomic data obtained from the genotyping of the wheat samples to pinpoint the physical and genetic positions of molecular markers associated with characteristics that are present in both types of wheat and in the crop’s wild relatives.
According to Sansaloni, on average, 72% of the markers obtained are uniquely placed on three molecular reference maps and around half of these are in interesting regions with genes that control specific characteristics of value to breeders, farmers and consumers, such as heat and drought tolerance, yield potential and protein content.
Open access
The data, analysis and visualization tools of the study are freely available to the scientific community for advancing wheat research and breeding worldwide.
“These resources should be useful in gene discovery, cloning, marker development, genomic prediction or selection, marker-assisted selection, genome wide association studies and other applications,” Sansaloni said.
The study was part of the SeeD and MasAgro projects and the CGIAR Research Program on Wheat (WHEAT), with the support of Mexico’s Secretariat of Agriculture and Rural Development (SADER), the United Kingdom’s Biotechnology and Biological Sciences Research Council (BBSRC), and CGIAR Trust Fund Contributors. Research and analysis was conducted in collaboration with the National Institute of Agricultural Botany (NIAB) and the James Hutton Institute (JHI).
About CIMMYT:
The International Maize and What Improvement Center (CIMMYT) is the global leader in publicly-funded maize and wheat research and related farming systems. Headquartered near Mexico City, CIMMYT works with hundreds of partners throughout the developing world to sustainably increase the productivity of maize and wheat cropping systems, thus improving global food security and reducing poverty. CIMMYT is a member of the CGIAR System and leads the CGIAR programs on Maize and Wheat and the Excellence in Breeding Platform. The Center receives support from national governments, foundations, development banks and other public and private agencies. For more information visit staging.cimmyt.org.
More than 11,000 scientists signed on to a recent report showing that planet Earth is facing a climate emergency and the United Nations warned that the world is on course for a 3.2 degree spike by 2100, even if 2015 Paris Agreement commitments are met.
Agriculture, forestry, and land-use change are implicated in roughly a quarter of global greenhouse gas emissions.
Agriculture also offers opportunities to mitigate climate change and to help farmers — particularly smallholders in developing and emerging economies who have been hardest hit by hot weather and reduced, more erratic rainfall.
Most of CIMMYT’s work relates to climate change, helping farmers adapt to shocks while meeting the rising demand for food and, where possible, reducing emissions.
Family farmer Geofrey Kurgat (center) with his mother Elice Tole (left) and his nephew Ronny Kiprotich in their 1-acre field of Korongo wheat near Belbur, Nukuru, Kenya. (Photo: Peter Lowe/CIMMYT)
Climate-resilient crops and farming practices
53 million people are benefiting from drought-tolerant maize. Drought-tolerant maize varieties developed using conventional breeding provide at least 25% more grain than other varieties in dry conditions in sub-Saharan Africa — this represents as much as 1 ton per hectare more grain on average. These varieties are now grown on nearly 2.5 million hectares, benefiting an estimated 6 million households or 53 million people in the continent. One study shows that drought-tolerant maize can provide farming families in Zimbabwe an extra 9 months of food at no additional cost. The greatest productivity results when these varieties are used with reduced or zero tillage and keeping crop residues on the soil, as was demonstrated in southern Africa during the 2015-16 El Niño drought. Finally, tolerance in maize to high temperatures in combination with drought tolerance has a benefit at least twice that of either trait alone.
Wheat yields rise in difficult environments. Nearly two decades of data from 740 locations in more than 60 countries shows that CIMMYT breeding is pushing up wheat yields by almost 2% each year — that’s some 38 kilograms per hectare more annually over almost 20 years — under dry or otherwise challenging conditions. This is partly through use of drought-tolerant lines and crosses with wild grasses that boost wheat’s resilience. An international consortium is applying cutting-edge science to develop climate-resilient wheat. Three widely-adopted heat and drought-tolerant wheat lines from this work are helping farmers in Pakistan, a wheat powerhouse facing rising temperatures and drier conditions; the most popular was grown on an estimated 40,000 hectares in 2018.
Climate-smart soil and fertilizer management. Rice-wheat rotations are the predominant farming system on more than 13 million hectares in the Indo-Gangetic Plains of South Asia, providing food and livelihoods for hundreds of millions. If farmers in India alone fine-tuned crop fertilizer dosages using available technologies such as cellphones and photosynthesis sensors, each year they could produce nearly 14 million tons more grain, save 1.4 million tons of fertilizer, and cut CO2-equivalent greenhouse gas emissions by 5.3 million tons. Scientists have been studying and widely promoting such practices, as well as the use of direct seeding without tillage and keeping crop residues on the soil, farming methods that help capture and hold carbon and can save up to a ton of CO2 emissions per hectare, each crop cycle. Informed by CIMMYT researchers, India state officials seeking to reduce seasonal pollution in New Delhi and other cities have implemented policy measures to curb the burning of rice straw in northern India through widespread use of zero tillage.
Farmers going home for breakfast in Motoko district, Zimbabwe. (Photo: Peter Lowe/CIMMYT)
Measuring climate change impacts and savings
In a landmark study involving CIMMYT wheat physiologists and underlining nutritional impacts of climate change, it was found that increased atmospheric CO2 reduces wheat grain protein content. Given wheat’s role as a key source of protein in the diets of millions of the poor, the results show the need for breeding and other measures to address this effect.
CIMMYT scientists are devising approaches to gauge organic carbon stocks in soils. The stored carbon improves soil resilience and fertility and reduces its emissions of greenhouse gases. Their research also provides the basis for a new global soil information system and to assess the effectiveness of resource-conserving crop management practices.
CIMMYT scientist Francisco Pinto operates a drone over wheat plots at CIMMYT’s experimental station in Ciudad Obregon, Mexico. (Photo: Alfonso Cortés/CIMMYT)
Managing pests and diseases
Rising temperatures and shifting precipitation are causing the emergence and spread of deadly new crop diseases and insect pests. Research partners worldwide are helping farmers to gain an upper hand by monitoring and sharing information about pathogen and pest movements, by spreading control measures and fostering timely access to fungicides and pesticides, and by developing maize and wheat varieties that feature genetic resistance to these organisms.
Viruses and moth larvae assail maize. Rapid and coordinated action among public and private institutions across sub-Saharan Africa has averted a food security disaster by containing the spread of maize lethal necrosis, a viral disease which appeared in Kenya in 2011 and quickly moved to maize fields regionwide. Measures have included capacity development with seed companies, extension workers, and farmers the development of new disease-resilient maize hybrids.
The insect known as fall armyworm hit Africa in 2016, quickly ranged across nearly all the continent’s maize lands and is now spreading in Asia. Regional and international consortia are combating the pest with guidance on integrated pest management, organized trainings and videos to support smallholder farmers, and breeding maize varieties that can at least partly resist fall armyworm.
New fungal diseases threaten world wheat harvests. The Ug99 race of wheat stem rust emerged in eastern Africa in the late 1990s and spawned 13 new strains that eventually appeared in 13 countries of Africa and beyond. Adding to wheat’s adversity, a devastating malady from the Americas known as “wheat blast” suddenly appeared in Bangladesh in 2016, causing wheat crop losses as high as 30% on a large area and threatening to move quickly throughout South Asia’s vast wheat lands.
A community volunteer of an agricultural cooperative (left) uses the Plantix smartphone app to help a farmer diagnose pests in his maize field in Bardiya district, Nepal. (Photo: Bandana Pradhan/CIMMYT)
Partners and funders of CIMMYT’s climate research
A global leader in publicly-funded maize and wheat research and related farming systems, CIMMYT is a member of CGIAR and leads the South Asia Regional Program of the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS).
CIMMYT receives support for research relating to climate change from national governments, foundations, development banks and other public and private agencies. Top funders include CGIAR Research Programs and Platforms, the Bill & Melinda Gates Foundation, Mexico’s Secretary of Agriculture and Rural Development (SADER), the United States Agency for International Development (USAID), the UK Department for International Development (DFID), the Australian Centre for International Agricultural Research (ACIAR), Cornell University, the German aid agency GIZ, the UK Biotechnology and Biological Sciences Research Council (BBSRC), and CGIAR Trust Fund Contributors to Window 1 &2.
One of the researchers behind the study, Yoseph Alemayehu, carries out a field survey in Ethiopia by mobile phone. (Photo Dave Hodson/CIMMYT)
TEXCOCO, Mexico — Using field and mobile phone surveillance data together with forecasts for spore dispersal and environmental suitability for disease, an international team of scientists has developed an early warning system which can predict wheat rust diseases in Ethiopia. The cross-disciplinary project draws on expertise from biology, meteorology, agronomy, computer science and telecommunications.
Reported this week in Environmental Research Letters, the new early warning system, the first of its kind to be implemented in a developing country, will allow policy makers and farmers all over Ethiopia to gauge the current situation and forecast wheat rust up to a week in advance.
The system was developed by the University of Cambridge, the UK Met Office, the Ethiopian Institute of Agricultural Research (EIAR), the Ethiopian Agricultural Transformation Agency (ATA) and the International Maize and Wheat Improvement Center (CIMMYT). It works by taking near real-time information from wheat rust surveys carried out by EIAR, regional research centers and CIMMYT using a smartphone app called Open Data Kit (ODK).
This is complemented by crowd-sourced information from the ATA-managed Farmers’ Hotline. The University of Cambridge and the UK Met Office then provide automated 7-day advance forecast models for wheat rust spore dispersal and environmental suitability based on disease presence.
All of this information is fed into an early warning unit that receives updates automatically on a daily basis. An advisory report is sent out every week to development agents and national authorities. The information also gets passed on to researchers and farmers.
Example of weekly stripe rust spore deposition based on dispersal forecasts. Darker colors represent higher predicted number of spores deposited. (Graphic: University of Cambridge/UK Met Office)
Timely alerts
“If there’s a high risk of wheat rust developing, farmers will get a targeted SMS text alert from the Farmers’ Hotline. This gives the farmer about three weeks to take action,” explained Dave Hodson, principal scientist with CIMMYT and co-author of the research study. The Farmers’ Hotline now has over four million registered farmers and extension agents, enabling rapid information dissemination throughout Ethiopia.
Ethiopia is the largest wheat producer in sub-Saharan Africa but the country still spends in excess of $600 million annually on wheat imports. More can be grown at home and the Ethiopian government has targeted to achieve wheat self-sufficiency by 2023.
“Rust diseases are a grave threat to wheat production in Ethiopia. The timely information from this new system will help us protect farmers’ yields, and reach our goal of wheat self-sufficiency,” said EIAR Director Mandefro Nigussie.
Wheat rusts are fungal diseases that can be dispersed by wind over long distances, quickly causing devastating epidemics which can dramatically reduce wheat yields. Just one outbreak in 2010 affected 30% of Ethiopia’s wheat growing area and reduced production by 15-20%.
The pathogens that cause rust diseases are continually evolving and changing over time, making them difficult to control. “New strains of wheat rust are appearing all the time — a bit like the flu virus,” explained Hodson.
In the absence of resistant varieties, one solution to wheat rust is to apply fungicide, but the Ethiopian government has limited supplies. The early warning system will help to prioritize areas at highest risk of the disease, so that the allocation of fungicides can be optimized.
Example of weekly stripe rust environmental suitability forecast. Yellow to Brown show the areas predicted to be most suitable for stripe rust infection. (Graphic: University of Cambridge/UK Met Office)
The cream of the crop
The early warning system puts Ethiopia at the forefront of early warning systems for wheat rust. “Nowhere else in the world really has this type of system. It’s fantastic that Ethiopia is leading the way on this,” said Hodson. “It’s world-class science from the UK being applied to real-world problems.”
“This is an ideal example of how it is possible to integrate fundamental research in modelling from epidemiology and meteorology with field-based observation of disease to produce an early warning system for a major crop,” said Christopher Gilligan, head of the Epidemiology and Modelling Group at the University of Cambridge and a co-author of the paper, adding that the approach could be adopted in other countries and for other crops.
“The development of the early warning system was successful because of the great collaborative spirit between all the project partners,” said article co-author Clare Sader-Allen, currently a regional climate modeller at the British Antarctic Survey.
“Clear communication was vital for bringing together the expertise from a diversity of subjects to deliver a common goal: to produce a wheat rust forecast relevant for both policy makers and farmers alike.”
This study was made possible through the support provided by the BBSRC GCRF Foundation Awards for Global Agriculture and Food Systems Research, which brings top class UK science to developing countries, the Delivering Genetic Gains in Wheat (DGGW) Project managed by Cornell University and funded by the Bill & Melinda Gates Foundation and the UK Department for International Development (DFID). The Government of Ethiopia also provided direct support into the early warning system. This research is supported by CGIAR Fund Donors.
ABOUT CIMMYT:
The International Maize and Wheat Improvement Center (CIMMYT) is the global leader in publicly-funded maize and wheat research and related farming systems. Headquartered near Mexico City, CIMMYT works with hundreds of partners throughout the developing world to sustainably increase the productivity of maize and wheat cropping systems, thus improving global food security and reducing poverty. CIMMYT is a member of the CGIAR System and leads the CGIAR Research Programs on Maize and Wheat and the Excellence in Breeding Platform. The Center receives support from national governments, foundations, development banks and other public and private agencies. For more information, visit staging.cimmyt.org.
ABOUT THE ETHIOPIAN INSTITUTE OF AGRICULTURAL RESEARCH (EIAR):
The Ethiopian Institute of Agricultural Research (EIAR) is one of the oldest and largest agricultural research institutes in Africa, with roots in the Ethiopian Agricultural Research System (EARS), founded in the late 1940s. EIAR’s objectives are: (1) to generate, develop and adapt agricultural technologies that focus on the needs of the overall agricultural development and its beneficiaries; (2) to coordinate technically the research activities of Ethiopian Agricultural Research System; (3) build up a research capacity and establish a system that will make agricultural research efficient, effective and based on development needs; and (4) popularize agricultural research results. EIAR’s vision is to see improved livelihood of all Ethiopians engaged in agriculture, agro-pastoralism and pastoralism through market competitive agricultural technologies.
Visitors at CIMMYT’s experimental station in Obregon, Mexico, where elite wheat lines are tested for new traits.
For a number of reasons, including limited interdisciplinary collaboration and a dearth of funding, revolutionary new plant research findings are not being used to improve crops.
“Translational research” — efforts to convert basic research knowledge about plants into practical applications in crop improvement — represents a necessary link between the world of fundamental discovery and farmers’ fields. This kind of research is often seen as more complicated and time consuming than basic research and less sexy than working at the “cutting edge” where research is typically divorced from agricultural realities in order to achieve faster and cleaner results; however, modern tools — such as genomics, marker-assisted breeding, high throughput phenotyping of crop traits using drones, and speed breeding techniques — are making it both faster and cost-effective.
In a new article in Crop Breeding, Genetics, and Genomics, wheat physiologist Matthew Reynolds of the International Maize and Wheat Improvement Center (CIMMYT) and co-authors make the case for increasing not only funding for translational research, but the underlying prerequisites: international and interdisciplinary collaboration towards focused objectives and a visionary approach by funding organizations.
“It’s ironic,” said Reynolds. “Many breeding programs have invested in the exact technologies — such as phenomics, genomics and informatics — that can be powerful tools for translational research to make real improvements in yield and adaptation to climate, disease and pest stresses. But funding to integrate these tools in front-line breeding is quite scarce, so they aren’t reaching their potential value for crop improvement.”
Members of the International Wheat Yield Partnership (IWYP) which focuses on translational research to boost wheat yields.
Many research findings are tested for their implications for wheat improvement by the International Wheat Yield Partnership (IWYP) at the IWYP Hub, a centralized technical platform for evaluating innovations and building them into elite wheat varieties, co-managed by CIMMYT at its experimental station in Obregon, Mexico.
IWYP has its roots with the CGIAR Research Program on Wheat (WHEAT), which in 2010 formalized the need to boost both wheat yield potential as well as its adaptation to heat and drought stress. The network specializes in translational research, harnessing scientific findings from around the world to boost genetic gains in wheat, and capitalizing on the research and pre-breeding outputs of WHEAT and the testing networks of the International Wheat Improvement Network (IWIN). These efforts also led to the establishment of the Heat and Drought Wheat Improvement Consortium (HeDWIC).
“We’ve made extraordinary advances in understanding the genetic basis of important traits,“ said IWYP’s Richard Flavell, a co-author of the article. “But if they aren’t translated into crop production, their societal value is lost.”
The authors, all of whom have proven track records in both science and practical crop improvement, offer examples where exactly this combination of factors led to the impactful application of innovative research findings.
Improving the Vitamin A content of maize: A variety of maize with high Vitamin A content has the potential to reduce a deficiency that can cause blindness and a compromised immune system. This development happened as a result of many translational research efforts, including marker-assisted selection for a favorable allele, using DNA extracted from seed of numerous segregating breeding crosses prior to planting, and even findings from gerbil, piglet and chicken models — as well as long-term, community-based, placebo-controlled trials with children — that helped establish that Vitamin A maize is bioavailable and bioefficacious.
Flood-tolerant rice: Weather variability due to climate change effects is predicted to include both droughts and floods. Developing rice varieties that can withstand submergence in water due to flooding is an important outcome of translational research which has resulted in important gains for rice agriculture. In this case, the genetic trait for flood tolerance was recognized, but it took a long time to incorporate the trait into elite germplasm breeding programs. In fact, the development of flooding tolerant rice based on a specific SUB 1A allele took over 50 years at the International Rice Research Institute in the Philippines (1960–2010), together with expert molecular analyses by others. The translation program to achieve efficient incorporation into elite high yielding cultivars also required detailed research using molecular marker technologies that were not available at the time when trait introgression started.
Other successes include new approaches for improving the yield potential of spring wheat and the discovery of traits that increase the climate resilience of maize and sorghum.
One way researchers apply academic research to field impact is through phenotyping. Involving the use of cutting edge technologies and tools to measure detailed and hard to recognize plant traits, this area of research has undergone a revolution in the past decade, thanks to more affordable digital measuring tools such as cameras and sensors and more powerful and accessible computing power and accessibility.
Scientists are now able to identify at a detailed scale plant traits that show how efficiently a plant is using the sun’s radiation for growth, how deep its roots are growing to collect water, and more — helping breeders select the best lines to cross and develop.
An Australian pine at CIMMYT’s experimental station in Texoco, Mexico, commemorates the 4th symposium of the International Plant Phenotyping Network.
Phenotyping is key to understanding the physiological and genetic bases of plant growth and adaptation and has wide application in crop improvement programs. Recording trait data through sophisticated non-invasive imaging, spectroscopy, image analysis, robotics, high-performance computing facilities and phenomics databases allows scientists to collect information about traits such as plant development, architecture, plant photosynthesis, growth or biomass productivity from hundreds to thousands of plants in a single day. This revolution was the subject of discussion at a 2016 gathering of more than 200 participants at the International Plant Phenotyping Symposium hosted by CIMMYT in Mexico and documented in a special issue of Plant Science.
There is currently an explosion in plant science. Scientists have uncovered the genetic basis of many traits, identified genetic markers to track them and developed ways to measure them in breeding programs. But most of these new findings and ideas have yet to be tested and used in breeding programs, wasting their potentially enormous societal value.
Establishing systems for generating and testing new hypotheses in agriculturally relevant systems must become a priority, Reynolds states in the article. However, for success, this will require interdisciplinary, and often international, collaboration to enable established breeding programs to retool. Most importantly, scientists and funding organizations alike must factor in the long-term benefits as well as the risks of not taking timely action. Translating a research finding into an improved crop that can save lives takes time and commitment. With these two prerequisites, basic plant research can and should positively impact food security.
Authors would like to acknowledge the following funding organizations for their commitment to translational research.
The International Wheat Yield Partnership (IWYP) is supported by the Biotechnology and Biological Sciences Research Council (BBSRC) in the UK; the U. S. Agency for International Development (USAID) in the USA; and the Syngenta Foundation for Sustainable Agriculture (SFSA) in Switzerland.
The Heat and Drought Wheat Improvement Consortium (HeDWIC) is supported by the Sustainable Modernization of Traditional Agriculture (MasAgro) Project by the Ministry of Agriculture and Rural Development (SADER) of the Government of Mexico; previous projects that underpinned HeDWIC were supported by Australia’s Grains Research and Development Corporation (GRDC).
The Queensland Government’s Department of Agriculture and Fisheries in collaboration with The Grains Research and Development Corporation (GRDC) have provided long-term investment for the public sector sorghum pre-breeding program in Australia, including research on the stay-green trait. More recently, this translational research has been led by the Queensland Alliance for Agriculture and Food Innovation (QAAFI) within The University of Queensland.
ASI validation work and ASI translation and extension components with support from the United Nations Development Programme (UNDP) and the Bill and Melinda Gates Foundation, respectively.
Financial support for the maize proVA work was partially provided by HarvestPlus (www.HarvestPlus.org), a global alliance of agriculture and nutrition research institutions working to increase the micronutrient density of staple food crops through biofortification. The CGIAR Research Program MAIZE (CRP-MAIZE) also supported this research.
The CGIAR Research Program on Wheat (WHEAT) is led by the International Maize and Wheat Improvement Center (CIMMYT), with the International Center for Agricultural Research in the Dry Areas (ICARDA) as a primary research partner. Funding comes from CGIAR, national governments, foundations, development banks and other agencies, including the Australian Centre for International Agricultural Research (ACIAR), the UK Department for International Development (DFID) and the United States Agency for International Development (USAID).
Elite wheat varieties at CIMMYT’s experimental station in Ciudad Obregon, in Mexico’s Sonora state. (Photo: Marcia MacNeil/CIMMYT)
In a new study, scientists have found that genome segments from a wild grass are present in more than one in five of elite bread wheat lines developed by the International Maize and Wheat Improvement Center (CIMMYT).
Scientists at CIMMYT and other research institutes have been crossing wild goat grass with durum wheat — the wheat used for pasta — since the 1980s, with the help of complex laboratory manipulations. The new variety, known as synthetic hexaploid wheat, boosts the genetic diversity and resilience of wheat, notoriously vulnerable due to its low genetic diversity, adding novel genes for disease resistance, nutritional quality and heat and drought tolerance.
The study, which aimed to measure the effect of these long-term efforts using state-of-the-art molecular technology, also found that 20% of CIMMYT modern wheat lines contain an average of 15% of the genome segments from the wild goat grass.
“We’ve estimated that one-fifth of the elite wheat breeding lines entered in international yield trials has at least some contribution from goat grass,” said Umesh Rosyara, genomic breeder at CIMMYT and first author of the paper, which was published in Nature Scientific Reports. “This is much higher than expected.”
Although the synthetic wheat process can help bring much-needed diversity to modern wheat, crossing with synthetic wheat is a complicated process that also introduces undesirable traits, which must later be eliminated during the breeding process.
“Many breeding programs hesitate to use wild relatives because undesirable genomic segments are transferred in addition to desirable segments,” said Rosyara. “The study results can help us devise an approach to quickly eliminate undesirable segments while maintaining desirable diversity.”
CIMMYT breeding contributions are present in nearly half the wheat sown worldwide, many of such successful cultivars have synthetic wheat in the background, so the real world the impact is remarkable, according to Rosyara.
“With this retrospective look at the development and use of synthetic wheat, we can now say with certainty that the best wheat lines selected over the past 30 years are benefiting from the genes of wheat’s wild relatives,” he explained. “Even more, using cutting-edge molecular marker technology, we should be able to target and capture the most useful genes from wild sources and better harness this rich source of diversity.”
Modern breeders tread in nature’s footsteps
The common bread wheat we know today arose when an ancient grain called emmer wheat naturally cross-bred with goat grass around 10,000 years ago. During this natural crossing, very few goat grass genes crossed over, and as a result, current bread wheat is low in diversity for the genome contributed by goat grass. Inedible and considered a weed, goat grass still has desirable traits including disease resistance and tolerance to climate stresses.
Scientists sought to broaden wheat’s genetic diversity by re-enacting the ancient, natural cross that gave rise to bread wheat, crossing improved durum wheat or primitive emmer with different variants of goat grass. The resulting synthetic wheats were crossed again with improved wheats to help remove undesirable wild genome segments.
Once synthetic wheat is developed, it can be readily crossed with any elite wheat lines thus serving as a bridge to transfer diversity from durum wheat and wild goat grass to bread wheat. This helps breeders develop high yielding varieties with desirable traits for quality varieties and broad adaption.
CIMMYT is the first to use wheat’s wild relatives on such a large scale, and the synthetic derivative lines have been used by breeding programs worldwide to develop popular and productive bread wheat varieties. One example, Chuanmai 42, released in China in 2003, stood as the leading wheat variety in the Sichuan Basin for over a decade. Other synthetic derivative lines such as Sokoll and Vorobey appear in the lineage of many successful wheat lines, contributing crucial yield stability — the ability to maintain high yields over time under varying conditions.
The successful, large-scale use of genes from wheat’s wild relatives has helped broaden the genetic diversity of modern, improved bread wheat nearly to the level of the crop’s heirloom varieties. This diversity is needed to combat future environmental, pest, and disease challenges to the production of a grain that provides 20% of the calories consumed by humans worldwide.
This work was supported by the CGIAR Research Program on Wheat (WHEAT) and Seeds of Discovery (SeeD), a multi-project initiative comprising MasAgro Biodiversidad, a joint initiative of CIMMYT and the Ministry of agriculture and rural development (SADER) through the MasAgro (Sustainable Modernization of Traditional Agriculture) project; the CGIAR Research Programs on Maize (MAIZE) and Wheat (WHEAT); and a computation infrastructure and data analysis project supported by the UK’s Biotechnology and Biological Sciences Research Council (BBSRC). CIMMYT’s worldwide partners participated in the evaluation of CIMMYT international wheat yield trials.
For more information, or to arrange interviews with the researchers, please contact:
About the CGIAR Research Program on Wheat
The CGIAR Research Program on Wheat (WHEAT) is led by the International Maize and Wheat Improvement Center (CIMMYT), with the International Center for Agricultural Research in the Dry Areas (ICARDA) as a primary research partner. Funding comes from CGIAR, national governments, foundations, development banks and other agencies, including the Australian Centre for International Agricultural Research (ACIAR), the UK Department for International Development (DFID) and the United States Agency for International Development (USAID).
About CIMMYT
The International Maize and Wheat Improvement Center (CIMMYT) is the global leader in publicly funded maize and wheat research and related farming systems. Headquartered near Mexico City, CIMMYT works with hundreds of partners throughout the developing world to sustainably increase the productivity of maize and wheat cropping systems, thus improving global food security and reducing poverty. CIMMYT is a member of CGIAR and leads the CGIAR Research Programs on Maize and Wheat, and the Excellence in Breeding Platform. The center receives support from national governments, foundations, development banks and other public and private agencies.
“Knowing which strain you have is critical information that can be incorporated into early warning systems and results in more effective control of disease outbreaks in farmer’s fields” said Dr. Dave Hodson, a rust pathologist at CIMMYT in Ethiopia and co-author of the paper “MARPLE, a point-of-care, strain-level disease diagnostics and surveillance tool for complex fungal pathogens.” Read more here.
