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New innovative crops could significantly reduce agriculture’s climate change impact and environmental footprint

Written by Julian Bañuelos-Uribe on . Posted in Press releases.

As the global population approaches the 10 billion mark, the reliance on fertilisers to boost agricultural production has become an essential, yet environmentally challenging, practice. A Century-long dependence on these additives has allowed food production to keep pace with the growth in human population. However, the use of fertilisers across various farming systems is now causing severe ecological stress. The leaching of nitrogen into natural ecosystems, coupled with the release of greenhouse gases, is pushing the Earth’s environmental limits to a critical threshold.

To address this, an ambitious new research initiative aims to shrink the nitrogen footprint of agriculture by developing a breakthrough technology based on nature’s own solutions: a natural process called biological nitrification inhibition (BNI). The Novo Nordisk Foundation has awarded CIMMYT a grant of up to USD 21.1 million to lead an innovation research initiative called CropSustaiN that is designed to reduce the nitrogen footprint of wheat cultivation.

“Success in this initiative could lead to a major shift in agricultural practices globally, benefiting both the planet and farmers’ livelihoods. In addition to using less fertiliser, cost for the farmer will be minimal because all the components are already in the seed. This initiative could, potentially, be extended from wheat cultivation to include other staple crops like maize and rice,” says Claus Felby, Senior Vice President, Biotech, Novo Nordisk Foundation.

“BNI could be a part of how we revolutionise nitrogen management in agriculture. It represents a genetic mitigation strategy that not only complement existing methods but also has the potential to decrease the need for synthetic fertilisers substantially. The mitigation potential of better nitrogen fertiliser management could be as impactful for the Global South as the Green Revolution,” explains Bram Govaerts, Director General, CIMMYT.

Revolutionary mitigation approach

Rooted in a seed-based genetic strategy, BNI leverages a plant’s innate ability to suppress soil nitrification through the release of natural compounds. This approach potentially promises to curb the use and leaching of synthetic nitrogen fertilisers—a significant contributor to greenhouse gas emissions and water pollution—without compromising wheat yield or soil vitality. The BNI-method contrasts with synthetic nitrification inhibitors and could offer a more scalable and cost-effective solution, potentially reducing nitrogen fertiliser usage by 20%, depending on regional farming conditions.

By harnessing the power of genetics in plant seeds, CropSustaiN leverages the natural process of BNI to develop new wheat varieties that require significantly less nitrogen fertiliser. Using conventional breeding, genes from wild crop relatives like wild rye, which have inherently better nitrogen use efficiency, are incorporated. CIMMYT makes such breeding products available to its global network of partners for the international public good.

The agenda for CropSustaiN includes validating BNI efficacy across diverse climates and integrating the technology into mainstream agricultural protocols. While the venture carries success risks, the potential rewards—ranging from widespread BNI adoption to valuable insights into nitrogen management—position it as a pioneering initiative. By ensuring that the seeds developed through this program are accessible to all farmers without exclusive patent rights, the Novo Nordisk Foundation is leading an inclusive approach to agricultural innovation.

CropSustaiN builds on the joint research by the Japan International Research Center for Agricultural Sciences (JIRCAS) and CIMMYT that started in 2015. The initiative has already yielded BNI wheat lines tested over three farming seasons. These innovative crops are now poised for further development and for scaling worldwide, indicating a potential paradigm shift in agricultural practices.

The Novo Nordisk Foundation has already laid the groundwork for CropSustaiN by funding related BNI research at CIMMYT, the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Aarhus University, the University of Aberdeen, and the University of Copenhagen -thus fostering an ecosystem for research innovation.

About the Novo Nordisk Foundation

Established in Denmark in 1924, the Novo Nordisk Foundation is an enterprise foundation with philanthropic objectives. The vision of the Foundation is to improve people’s health and the sustainability of society and the planet. The Foundation’s mission is to progress research and innovation in the prevention and treatment of cardiometabolic and infectious diseases as well as to advance knowledge and solutions to support a green transformation of society.

www.novonordiskfonden.dk/en

About CIMMYT

CIMMYT is a cutting edge, non-profit, international organization dedicated to solving tomorrow’s problems today. It is entrusted with fostering improved quantity, quality, and dependability of production systems and basic cereals such as maize, wheat, triticale, sorghum, millets, and associated crops through applied agricultural science, particularly in the Global South, through building strong partnerships. This combination enhances the livelihood trajectories and resilience of millions of resource-poor farmers, while working towards a more productive, inclusive, and resilient agrifood system within planetary boundaries. CIMMYT is a core CGIAR Research Center, a global research partnership for a food-secure future, dedicated to reducing poverty, enhancing food and nutrition security, and improving natural resources. For more information, visit staging.cimmyt.org.

Further information 

Jakob Stein, Communications Specialist, jse@novo.dk

CIMMYT joins global efforts to curb greenhouse emissions and strengthen food systems

Written by Julian Bañuelos-Uribe on . Posted in News.

The 2023 UN Climate Change Conference (COP 28) took place from November 30 to December 12, 2023, in Dubai, UAE. The conference arrived at a critical moment when over 600 million people face chronic hunger, and global temperatures continue to rise at alarming rates. CIMMYT researchers advocated for action into agriculture’s mitigating role in climate change, increasing crop diversity, and bringing the tenets of sustainability and regenerative agroecological production systems to a greater number of farmers.

Directly addressing the needs of farmers, CIMMYT proposed the creation of an advanced data management system, training, and protocols for spreading extension innovations such as digital approaches and agronomic recommendations to farmers via handheld devices to harmonize the scaling in Africa of regenerative agriculture—diverse practices whose outcomes include better productivity and environmental quality, economic feasibility, social inclusivity, and nutritional security.

CIMMYT presented research showing that in times of fertilizer shortages, targeting nitrogen supplies from inorganic and organic sources to farms with minimal access to nitrogen inputs can improve nitrogen-use efficiency and helps maintain crop yields while limiting harm from excesses in fertilizer use. Examining how food production is driving climate change, CIMMYT promoted ways to lessen climate shocks, especially for smallholder farmers who inordinately suffer the effects of climate change, including rising temperatures and extended droughts. Improved, climate-resilient crop varieties constitute a key adaptation. Boosting farmer productivity and profits is a vital part of improving rural livelihoods in Africa, Asia, and Latin America.

When asked about CIMMYT’s contribution to COP 28, Bram Govaerts, CIMMYT’s director general, highlighted the inclusion of agriculture in the COP28 UAE Declaration on Sustainable Agriculture, Resilient Food Systems, and Climate Action as part of various potential solutions for climate change, an effort that CIMMYT supported through advocacy with leaders and government officials.

“Our participation addressed some of the pressure points which led to this significant recognition. It further cleared our role as an active contributor to discussions surrounding the future of food and crop science,” said Govaerts.

Unlocking the potential of crop genetic diversity

“The diversity stored in today’s gene banks contains the potential to unlock genes that can withstand drought and warmer temperatures,” said Sarah Hearne, CIMMYT’s director of Genetic Resources at a side-event: Crop diversity for climate change adaptation and mitigation contributing to resilient and nature positive futures for farmers globally.

Sarah Hearne presents on the potential of crop diversity to help combat climate change impacts on agrifood systems. (Photo: Food Pavilion/COP 28)

Hearne explained the process that characterizes plant DNA to identify the ideal, climate-adaptable breeding traits. This classification system also opens the door for genetic modeling, which can predict key traits for tomorrow’s climatic and environmental conditions.

“Our thinking must shift from thinking of gene banks to banks of genes, to make vibrant genetic collections for humanity, opening up genetic insurance for farmers,” said Hearne.

Working towards a food system that works for the environment

With an increased strain on food production, sustainability becomes critical for long-term human and environmental health. Sarah Hearne and Tek Sapkota, agricultural systems and climate change senior scientist, from CIMMYT participated in a panel discussion: Responsible consumption and sustainable production: pathways for climate-friendly food systems. They shared how progress in genetic innovation and fertilizer use can contribute to sustainable consumption and a resilient food system.

Fertilizer use remains highly skewed, with some regions applying more fertilizer than required and others, like sub-Saharan Africa, not having sufficient access, resulting in low crop yields. However, to achieve greater food security, the Global South must produce more food. For that, they need to use more fertilizer. Just because increased fertilizer use will increase greenhouse gases (GHGs) emissions, institutions cannot ask smallholder farmers not to increase fertilizer application. Increased GHGs emission with additional fertilizer application in low-input areas can be counterbalanced by improving Nutrient-Use Efficiency (NUE) in high-output areas thereby decreasing GHGs emissions. This way, we can increase global food production by 30% ca with the current level of fertilizer consumption.

Tek Sapkota speaks on how sustainable and efficient fertilizer use can contribute to a resilient food system. (Photo: Food Pavilion/COP 28)

“This issue needs to be considered through a holistic lens. We need to scale-up already proven technologies using digital extensions and living labs and linking farmers with markets,” said Sapkota.

On breeding climate-resilient seeds, Hearne addressed whether farmers are accepting new seeds and how to ensure their maximum adoption. Hearne detailed the partnership with CGIAR and NARS and the numerous technologies advancing the selection of ideal breeding traits, considering shortened breeding cycles, and responding to local needs such as heat or flood tolerance, and traditional preferences.

“Drought-tolerant maize, developed by CIMMYT and the International Institute of Tropical Agriculture (IITA), has benefited over 8 million households in sub-Saharan Africa, which proves that farmers are increasingly receptive to improved seeds. With a better selection of appropriate traits, we can further develop and distribute without yield penalties,” said Hearne.

Regenerative and agroecological production systems

Researchers have studied regenerative and agroecological production systems for decades, with new and old research informing current debates. These systems restore and maintain ecosystems, improving resource use efficiency, strengthening resilience, and increasing self-sufficiency. In his keynote presentation, Sapkota presented 3 examples of regenerative agriculture and agroecological systems:  conservation agriculture, cropping system diversification and site-specific nutrient management and their impact on food production, climate change adaptation and mitigation.

“As the science continues to develop, we need to harness digital capacity to co-create sustainable solutions alongside local, indigenous knowledge,” said Sapkota. “While we should continue research and innovation on cutting-edge science and technologies, we should also invest in knowledge sharing networks to spread access to this research; communication is fundamental for further adoption of these practices.”

Soybean rust threatens soybean production in Malawi and Zambia

Written by Julian Bañuelos-Uribe on . Posted in Blogs.

Healthy soybean fields. (Photo: Peter Setimela/CIMMYT)

Soybeans are a significant source of oil and protein, and soybean demand has been increasing over the last decade in Malawi and Zambia. Soybean contributes to human nutrition, is used in producing animal feed, and fetches a higher price per unit than maize, thus serving as a cash crop for smallholder farmers. These are among the main factors contributing to the growing adoption of soybean among smallholder producers. In addition, soybean is a vital soil-fertility improvement crop used in crop rotations because of its ability to fix atmospheric nitrogen. To a large extent, soybean demand outweighs supply, with the deficit covered by imports.

Soybean production in sub-Saharan Africa is expected to grow by over 2% per annum to meet the increasing demand. However, as production increases, significant challenges caused by diseases, pests, declining soil fertility, and other abiotic factors remain. According to official government statistics, Zambia produces about 450,000 tonnes of soybean per annum, with an estimated annual growth of 14%. According to FAOSTAT, this makes Zambia the second largest soybean producer in the southern African region. Although soybean was traditionally grown by large commercial farmers in Zambia, smallholders now account for over 60% of the total annual soybean production.

Production trends show that smallholder soybean production increased rapidly in the 2015–2016 season, a period that coincided with increased demand from local processing facilities. As smallholder production continued to increase, in 2020, total output by smallholder farmers outpaced that of large-scale farmers for the first time and has remained dominant over the last two seasons (Fig 1). However, soybean yields among smallholder farmers have remained low at around 1 MT/HA.

Figure 1. Soybean production trends by smallholders and large-scale farmers. (Photo: Hambulo Ngoma/Zambia Ministry of Agriculture, Crop Forecast Survey)

Soybean production in the region is threatened by soybean rust caused by the fungus Phakopsora pachyrhizi. The rust became prevalent in Africa in 1996; it was first confirmed in Uganda on experimental plots and subsequently on farmers’ fields throughout the country. Monitoring efforts in the U.S. have saved the soybean industry millions of dollars in fungicide costs due to the availability of accurate disease forecasting based on pathogen surveillance and environmental data.

Soybean rust disease is spread rapidly and easily by wind, and most available varieties grown by farmers are susceptible. The above-normal rainfall during the 2022–2023 season was conducive to the spread of the fungus. A recent survey of over 1,000 farm households shows that 55% and 39% of farmers in Zambia and Malawi, respectively, were affected by soybean rust during the 2022–2023 season. The lack of rust-tolerant varieties makes production expensive for smallholder farmers who cannot afford to purchase fungicides to control the pathogens. It is estimated that soybean rust can cause large yield losses of up to 90%, depending on crop stage and disease severity. Symptoms due to soybean rust infection may be observed at any developmental stage of the plant, but losses are mostly associated with infection from the flowering stage to the pod-filling stage.

Soybean plants affected by soy rust. (Photo: Peter Setimela)

Mitigation measures using resistant or tolerant varieties have been challenging because the fungus mutates very rapidly, creating genetic variability. Although a variety of fungicides effective against soybean rust are available, the use of such fungicides is limited due to the high cost of the product and its application, as well as to environmental concerns. Due to this restricted use of fungicide, an early monitoring system for detecting rust threats for steering fungicide might only be relevant for large-scale producers in eastern and southern Africa. With the massive increase in the area under soybean production, soybean rust is an important disease that cannot be ignored. Host-plant resistance provides a cheaper, more environmentally friendly, and much more sustainable approach for managing soybean rust in smallholder agriculture that characterizes the agricultural landscape of eastern and southern Africa.

To advance the use of rust-tolerant varieties, the Southern Africa Accelerated Innovation Delivery Initiative (AID-I) Rapid Delivery Hub, or MasAgro Africa, is presently concluding surveys to assess farmers’ demand and willingness to pay for rust-tolerant varieties in Malawi and Zambia. The results from this assessment will be valuable to seed companies and last-mile delivery partners to gain a better understanding of what farmers need and to better serve the farmers.  This coming season AID-I will include rust tolerant varieties in the mega-demonstrations to create awareness about new varieties that show some tolerance to rust.

Preventing nitrogen loss in maize

Written by Julian Bañuelos-Uribe on . Posted in Publications.

The widespread availability of chemical nitrogen fertilizers is a prime driver of the vast improvement of crop yields over the past 50 years. However, their use has come with a price, as nitrogen escaping into surrounding soil and air has negative impacts on the environment and human health, including water pollution, depletion of soil-fertility, and greenhouse gas emissions.

Researchers from CIMMYT and JIRCAS (Japan International Research Center for Agricultural Science) examined ways to curtail the leakage of nitrogen into ecosystems, through a process called biological nitrification inhibition (BNI) in the paper “Genetic variation among elite inbred lines suggests potential to breed for BNI-capacity in maize,” published in the journal Scientific Reports on August 17, 2023.

César Daniel Petroli, leader and specialist in high-throughput genotyping/sequencing at the Genetic Analysis Service for Agriculture (SAGA) laboratory at CIMMYT with scientists. (Photo: Alfredo Sáenz)

BNI is a plant-based natural process that reduces nitrogen losses, which can reduce fertilizer demand while sustaining agricultural systems. The roots of plants that exhibit BNI activity release natural substances that inhibit the activity of nitrifying bacteria in soil, thus reducing the amount of nitrogen lost to the surrounding ecosystem. Many plant species have natural BNI activity in their roots.

Although synthetic chemical nitrification inhibitors are commercially available to reduce nitrogen losses, the high costs of this approach have limited its adoption. By contrast, breeding new varieties with increased natural BNI activity can offer a practical and economical approach to reduce nitrogen fertilizer need and waste.

“We are in the discovery phase regarding BNI activity and its determining traits for maize. Such information is crucial to pave the way for breeding programs and genetic improvement efforts,” said Kevin Pixley, co-author of the paper and former director of CIMMYT’s Genetic Resources Program. “We need to identify genetic markers for BNI compounds including ‘zeanone’, which will enable breeders to develop maize varieties that require and waste less nitrogen fertilizer, while achieving high yields.”

Doubles haploids prepared for evaluation and further analysis at CIMMYT’s headquarters, El Batán, Mexico. (Photo: Araceli Balderas)

This research identified 18 single nucleotide polymorphisms (SNP) that act as genetic “signposts” for breeders to use to accelerate and increase the accuracy of breeding to increase BNI activity for maize. The researchers also identified six “candidate” or putative genes associated with BNI activity and related to nitrogen use efficiency, thereby enhancing the understanding of the genetics controlling BNI activity.

“Our identification of SNPs and genes that regulate how maize processes nitrogen begins to draw a road map to guide the development of molecular markers for use in breeding new maize varieties that meet farmer and consumer needs at a lower environmental cost,” said senior author Cesar Petroli. “Building on the results obtained and reported in our recent publication, we are developing maize (doubled haploid) populations to refine the genetic map for BNI activity in maize”.

This research was conducted with partners from JIRCAS and the Universidad de la República, Uruguay.

Improved nitrogen use can boost tomato yields

Written by Sarah McLaughlin on . Posted in Publications.

Nitrogen use efficiency (NUE) and tomato production in Nepal have both been negatively affected by universal fertilizer recommendations that do not consider the soil type, nutrient status, or climate and crop management practices. Improved use of appropriate levels of nitrogen (N) fertilizer, application time, and application methods could increase yields and reduce environmental impact.

Scientists from the International Maize and Wheat Improvement Center (CIMMYT), the Nepal Agricultural Research Council (NARC), the National Soil Science Research Center (NSSRC), and the International Fertilizer Development Center completed a study to identify the optimum N rate and application method to increase NUE and tomato crop yield as part of the Nepal Seed and Fertilizer (NSAF) project.

Randomized trials with nine treatments across five districts included the omission of N, phosphorus (P) and potassium (K) (N0, P0, K0), variable N rates of 100, 150, 200 and 250 kg ha−1 (N-100, N-150, N-200 and N-250), use of urea briquettes (UB) with deep placement (UBN-150) and a control (CK).

Considering its anticipated higher NUE, N input in UB was reduced from the recommend N rate of 200 kg ha−1 by a quarter. N was revealed as the most limiting plant nutrient based on yield responses from an NPK omission plot.

Tomato yield was increased by 27 percent, 35 percent, 43 percent, and 27 percent over N0 with respective applications of fertilizer at N-100, N-150, N-200 and N-250. Yields responded quadratically to the added N fertilizers, with optimum rates ranging from 150 to 200 kg ha−1.

UBN-150 produced a similar yield to the recommended rate of N-200 and significantly increased tomato yield by 12% over N-150.

At N-100, scientists observed the highest partial factor productivity of N (PFPN), while at N-200, the highest agronomic efficiency of N (AEN) was recorded.

Results suggest that there is opportunity to develop more efficient N fertilization strategies for Nepal, leading to benefits of higher yields and less environmental damage.

Read the study: Optimum Rate and Deep Placement of Nitrogen Fertilizer Improves Nitrogen Use Efficiency and Tomato Yield in Nepal

Cover photo: Generic, non-specific recommendations for fertilizer use in Nepal have affected the production of tomato crops. (Photo: Dilli Prasad Chalise/CIMMYT)

Sustainability of rice production in the Northwestern Indo-Gangetic Plains

Written by Sarah McLaughlin on . Posted in Publications.

Rice is a vital crop for India, contributing around 30 percent of calories consumed in the country and providing a crucial source of income from exports. However, due to climate change and conversion of land for other uses, rice growing area in India is projected to decline by 6-7 million hectares (ha) by 2050, while production must increase by 1.1% annually over the next four decades to achieve rice self-sufficiency for the country.

As there is limited opportunity to horizontal expansion of cultivable land, the predicted increase in demand must be met through increasing rice yields in regions with low yields and maintaining existing yields in high-yielding areas. This must be achieved using sustainable farming practices: currently, 90 percent of total greenhouse gas (GHG) emissions of monsoon season cropped cereals in India is caused by rice cultivation, as is 80 percent of the energy and water used in agriculture.

Scientists found that in the Northwestern Indo-Gangetic Plains (IGP) of India, yield gaps were small (ca. 2.7 t ha−1, or 20% of potential yield) mainly because of intensive production system with high input use. Using management data from 4,107 individual farmer fields, the study highlighted scope to reduce nitrogen (N) inputs without compromising yields in this intensive production system.

Findings show evidence of and methodology for the quantification of yield gaps and approaches that can improve resource-use efficiency, providing a possible alternative approach that could be reproduced elsewhere for other crops and contexts. It is recommended that future research focuses on ways to reduce other production inputs without compromising the yields in such intensive production systems.

This paper is the result of Harishankar Nayak’s PhD training in collaboration with the Indian Council of Agricultural Research (ICAR) jointly supervised by the researchers at the Indian Agricultural Research Institute (IARI) and International Maize and Wheat Improvement Center (CIMMYT).

Read the study: Rice yield gaps and nitrogen-use efficiency in the Northwestern Indo-Gangetic Plains of India: Evidence based insights from heterogeneous farmers’ practices

Cover photo: A farmer stands in his rice field at a Climate-Smart Village in the Vaishali district of Bihar, India, as part of the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS). (Photo: DK Singh/CIMMYT)

Using ENM principles to preserve soil health

Written by Sarah McLaughlin on . Posted in Publications.

In a new Frontiers publication, scientists from the International Maize and Wheat Improvement Center (CIMMYT) outline how to achieve an ecologically based approach to sustainable management of soil fertility, particularly for smallholders.

What is ecological nutrient management (ENM)?

Across the globe, smallholder farming communities only have limited resources to improve their financial and food security, and soil degradation is common. Ecological nutrient management (ENM), an agroecological approach to managing the biogeochemical cycles that regulate soil ecosystem services and soil fertility, can prevent degradation and preserve soil health.

Five principles guide ENM strategies:

  • Building soil organic matter and other nutrient reserves.
  • Minimizing the size of nitrogen (N) and phosphorus (P) pools that are most vulnerable to loss.
  • Maximize agroecosystem capacity to use soluble, inorganic N and P.
  • Use functional biodiversity to maximize presence of growing plants, biologically fix nitrogen and access sparingly soluble phosphorus.
  • Construct agroecosystem and field scale mass balances to track net nutrient flows over multiple growing seasons.
At the ICRISAT headquarters in Patencheru, India, M.L. Jat and Sieg Snapp stand in front on pigeonpea (Cajanus cajan) varieties, a semi-perennial legume that fixes nitrogen and solubilizes phosphorus for greater nutrient efficiency while building soil health. (Photo: Alison Laing/CSIRO)

Using functionally designed polycultures, diversified rotations, reduced fallow periods, increased reliance on legumes, integrated crop-livestock production, and use of a variety of soil amendments exemplify how ENM works in practice. A key principle is to underpin agroecosystem resilience through the promotion of soil organic matter accrual and restoration of soil function.

Strategic increases of spatial and temporal plant species diversity are used, that meet farmer requirements. This often involves perennial or semi-perennial bushes and vines that provide food, fuel and fodder while restoring soil fertility. ENM long-term management systems can increase yields, yield stability, profitability, and food security, thus addressing a range of smallholder needs.

Read the study: Advancing the science and practice of ecological nutrient management for smallholder farmers

Cover photo: A maize-bean intercrop that exemplifies the ENM approach, taken at CIMMYT’s Chiapas Hub, a long-term field experiment. (Photo: Sieg Snapp/CIMMYT)

Study explores how to reduce GHG emissions while supporting food security through nitrogen management

Written by Sarah McLaughlin on . Posted in Publications.

Use of fertilizer nitrogen (N) in farming is essential for food production but also contributes to climate crisis through GHG emissions. Synthetic nitrogen fertilizer accounts for 2.4 percent of global emissions, while its supply chain accounts for 21.5% of the annual direct emissions from agriculture.

One potential solution for developing appropriate N management strategies is yield-scaled nitrous oxide (N₂O) emission (YSNE), which has been recognized for its potential to balance food security and mitigate emissions. Improving understanding and use of YSNE under various field conditions is an essential part of widespread adoption of this approach.

Scientist working in the Sustainable Agrifood Systems (SAS) program at the International Maize and Wheat Improvement Center (CIMMYT) together with Hawassa University, Ethiopia and Landcare Research, New Zealand  assessed the relationship between N inputs and YSNE with published results and identified response patterns of YSNE to N inputs based on 1,800 observations from maize, rice and wheat crops at global scale.

Type 1 measures: increasing yields without changing N₂O emissions. Type 2 measures: reducing N₂O emissions without changing yields. Type 3 measures: both increasing yields and reducing N₂O emissions. (Photo: CIMMYT)

A positive relationship between N inputs and YSNE was evidenced in more than 60% of the dataset across all three crops, while a small proportion had an optimum N rate that minimized YSNE. Type of crop, annual mean temperature and soil N content affected the background yield-scale N₂O emission with higher soil temperature and N content leading to higher BYSNE. The analyses suggest that YSNE can be reduced by increasing yields, by reducing N₂O emissions and both by increasing yields and reducing N₂O emissions. The results of this study suggest appropriate N management strategies, yields, and N2O emissions.

Read the full article: Understanding response of yield-scaled N₂O emissions to nitrogen input: Data synthesis and introducing new concepts of background yield-scaled N₂O emissions and N₂O emission-yield curve

Cover photo: Woman using spreader for fertilizer application in India. (Photo: Wasim Iftikar/CSISA)

A farmer in the Ara district, in India's Bihar state, applies NPK fertilizer, composed primarily of nitrogen, phosphorus and potassium. (Photo: Dakshinamurthy Vedachalam/CIMMYT)

Biological nitrogen fixation and prospects for ecological intensification in cereal-based cropping systems

Written by Sarah McLaughlin on . Posted in Publications.

Among the inputs needed for a healthy soil, nitrogen is unique because it originates from the atmosphere. How it moves from the air to the ground is governed in part by a process called biological nitrogen fixation (BNF), which is catalyzed by specific types of bacteria.

Nitrogen supply is frequently the second most limiting factor after water availability constraining crop growth and so there is great farmer demand for accessible sources of nitrogen, such as synthetic nitrogen in fertilizer. This increasing demand has continued as new cereal varieties with higher genetic yield potential are being released in efforts to feed the world’s growing population.

Currently, the primary source for nitrogen is synthetic, delivered through fertilizers. Synthetic nitrogen revolutionized cereal crop (e.g., wheat, maize, and rice) production by enhancing growth and grain yield as it eliminated the need to specifically allocate land for soil fertility rejuvenation during crop rotation. However, synthetic nitrogen is not very efficient, often causing excess application, which leads to deleterious forms, including ammonia, nitrate, and nitrogen oxides escaping into the surrounding ecosystem, resulting in a myriad of negative impacts on the environment and human health. Nitrogen loss from fertilizer is responsible for a nearly 20% increase in atmospheric nitrous oxide since the industrial revolution. Notably, more nitrogen from human activities, including agriculture, has been released to the environment than carbon dioxide during recent decades, leading climate scientists to consider the possibility that nitrogen might replace carbon as a prime driver of climate change.

New research co-authored by International Maize and Wheat Improvement Center (CIMMYT) scientists, published in Field Crops Research, posits that facilitating natural methods of gathering useable nitrogen in BNF can reduce the amount of synthetic nitrogen being used in global agriculture.

As agricultural systems become more intensive regarding inputs and outputs, synthetic nitrogen has become increasingly crucial, but there are still extensive areas in the world that cannot achieve food and nutrition security because of a lack of nitrogen.

“This, together with increasing and changing dietary demands, shows that the future demand for nitrogen will substantially grow to meet the anticipated population of 9.7 billion people by the middle of the century,” said J.K. Ladha, adjunct professor in the Department of Plant Sciences at University of California, Davis, and lead author of the study.

Before the synthetic nitrogen, the primary source of agricultural nitrogen was gathered through BNF as bacteria living underground that convert atmospheric nitrogen into nitrogen that can be utilized by crops. Therefore, legumes are often employed as a cover crop in rotating fields to replenish nitrogen stocks; their root systems are hospitable for these nitrogen producing bacteria to thrive.

“There are ways in which BNF could be a core component of efforts to build more sustainable and regenerative agroecosystems to meet nitrogen demand with lower environmental footprints,” said Timothy Krupnik, Senior System Agronomist at CIMMYT in Dhaka, Bangladesh.

Plant scientists have often hypothesized that the ultimate solution for solving the ever-growing nitrogen supply challenge is to confer cereals like wheat, maize, rice, with their own capacity for BNF. Recent breakthroughs in the genomics of BNF, as well as improvements in the understanding how legumes and nitrogen bacteria interact, have opened new avenues to tackle this problem much more systematically.

“Enabling cereal crops to capture their own nitrogen is a long-standing goal of plant biologists and is referred to as the holy grail of BNF research,” said P.M. Reddy, Senior Fellow at The Energy Research Institute, New Delhi. “The theory is that if cereal crops can assemble their own BNF system, the crop’s internal nitrogen supply and demand can be tightly regulated and synchronized.”

The study examined four methods currently being employed to establish systems within cereal crops to capture and use their own nitrogen, each with their advantages and limitations. One promising method involves identifying critical plant genes that perceive and transmit nitrogen-inducing signals in legumes. Integrating these signal genes into cereal crops might allow them to construct their own systems for BNF.

“Our research highlights how BNF will need to be a core component of efforts to build more sustainable agroecosystems,” said Mark Peoples, Honorary Fellow at The Commonwealth Scientific and Industrial Research Organisation (CSIRO), Canberra, Australia. “To be both productive and sustainable, future cereal cropping systems will need to better incorporate and leverage natural processes like BNF to mitigate the corrosive environmental effects of excess nitrogen leaking into our ecosystems.”

Besides the efforts to bring BNF to cereals, there are basic agronomic management tools that can shift focus from synthetic to BNF nitrogen.

“Encouraging more frequent use of legumes in crop rotation will increase diversification and the flow of key ecosystem services, and would also assist the long-term sustainability of cereal-based farming systems­,” said Krupnik.

Read the study: Biological nitrogen fixation and prospects for ecological intensification in cereal-based cropping systems

Cover photo: A farmer in the Ara district, in India’s Bihar state, applies NPK fertilizer, composed primarily of nitrogen, phosphorus and potassium. (Photo: Dakshinamurthy Vedachalam/CIMMYT)

Galvanized leaf storage proteins serve as a nutrient lifeline for maize under drought, recent study says

Written by Mike Listman on . Posted in Publications.

For the first time ever, a biotechnology team has identified vegetative storage proteins (VSP) in maize and activated them in the leaves to stockpile nitrogen reserves for release when plants are hit by drought, which also causes nutrient stress, according to a recent report in Plant Biotechnology Journal. In two years of field testing, the maize hybrids overexpressing the VSP in leaf cells significantly out-yielded the control siblings under managed drought stress applied at the flowering time, according to Kanwarpal Dhugga, a principal scientist at the International Maize and Wheat Improvement Center (CIMMYT).

“One of the two most widely grown crops, maize increasingly suffers from erratic rainfall and scarcer groundwater for irrigation,” Dhugga said. “Under water stress, nitrogen availability to the plant is also attenuated. If excess nitrogen could be stored in the leaves during normal plant growth, it could help expedite the plant’s recovery from unpredictable drought episodes. In our experimental maize hybrids, this particular VSP accumulated to more than 4% in mesophyll cells, which is five times its normal levels, and offered an additional, dispensable source of nitrogen that buffered plants against water deficit stress.”

Dhugga noted as well that the study, whose authors include scientists from Corteva Agriscience, the Bill & Melinda Gates Foundation, and the US Department of Agriculture (USDA), provides experimental evidence for the link between drought tolerance and adequate nitrogen fertilization of crop plants. “This mechanism could also help farmers and consumers in sub-Saharan Africa, where maize is grown on nearly 40 million hectares, accounts for almost one-third of the region’s caloric intake, and frequently faces moderate to severe drought.”

Scientists multiply and power up vegetative storage proteins in maize leaves as nutrient stockpiles for drought-stressed maize crops. Graphic adapted from: Pooja Gupta, Society for Experimental Biology (SEB).

Read the full study:
A vegetative storage protein improves drought tolerance in maize.

BNI-enhanced wheat research wins 2021 Cozzarelli Prize

Written by Rodrigo Ordóñez on . Posted in News.

The paper “Enlisting wild grass genes to combat nitrification in wheat farming: A nature-based solution” received the 2021 Cozzarelli Prize, which recognizes outstanding articles published in the journal Proceedings of the National Academy of Sciences of the United States of America (PNAS). The paper was published as a joint research collaboration of Japan International Research Center for Agricultural Sciences (JIRCAS), the International Maize and Wheat Improvement Center (CIMMYT), the University of the Basque Country (UPV/EHU) and Nihon University.

The study identifies of a chromosomal region that regulates the biological nitrification inhibition (BNI) ability of wheat grass (Leymus racemosus), a wild relative of wheat. It also outlines the development of the world’s first BNI-enhanced wheat, through intergeneric crossing with a high-yielding wheat cultivar.

This research result is expected to contribute to the prevention of nitrogen pollution that leads to water pollution and greenhouse gas emissions, reducing the use of nitrogen fertilizer while maintaining productivity.

Best of the year

PNAS is one of the most cited scientific journals in the world, publishing more than 3,000 papers per year on all aspects of science. A total of 3,476 papers were published in 2021, covering six fields: Physical and Mathematical Sciences, Biological Sciences, Engineering and Applied Sciences, Biomedical Sciences, Behavioral and Social Sciences, and Applied Biological, Agricultural and Environmental Sciences.

The Cozzarelli Prize was established in 2005 as the PNAS Paper of the Year Prize and renamed in 2007 to honor late editor-in-chief Nicholas R. Cozzarelli. It is awarded yearly by the journal’s Editorial Board to one paper from each field reflecting scientific excellence and originality. The BNI research paper received the award in the category of Applied Biological, Agricultural, and Environmental Sciences.

The awards ceremony will be held online on May 1, 2022, and a video introducing the results of this research will be available.

Recently, lead researcher Guntur V. Subbarao presented this research on a talk at Princeton University’s Center for Policy Research on Energy and the Environment: “Low-nitrifying agricultural systems are critical for the next Green Revolution.”

Fruitful collaboration

CIMMYT has collaborated with JIRCAS on BNI-enhanced wheat research since 2009, with funding from Japan’s Ministry of Agriculture, Forestry and Fisheries. CIMMYT is one of the founding members of the BNI Consortium, established in 2015.

The CGIAR Research Programs on Wheat (WHEAT) and Maize (MAIZE) co-funded BNI research since 2014 and 2019 respectively, until their conclusion at the end of 2021.

BNI research has been positioned in the “Measures for achievement of Decarbonization and Resilience with Innovation (MeaDRI)” strategy of Japan’s Ministry of Agriculture, Forestry and Fisheries, and was also selected as one of the ministry’s “Top 10 agricultural technology news for 2021.”

Read the full article:
Enlisting wild grass genes to combat nitrification in wheat farming: A nature-based solution

Nitrogen-efficient wheats can provide more food with fewer greenhouse gas emissions, new study shows

Written by Rodrigo Ordóñez on . Posted in Press releases.

An international collaboration has discovered and transferred to elite wheat varieties a wild-grass chromosome segment that causes roots to secrete natural inhibitors of nitrification, offering a way to dial back on heavy fertilizer use for wheat and to reduce the crop’s nitrogen leakage into waterways and air, while maintaining or raising its productivity and grain quality, says a new report in the Proceedings of the National Academy of Sciences of the United States of America.

Growing wheat varieties endowed with the biological nitrification inhibition (BNI) trait could increase yields in both well-fertilized and nitrogen-poor soils, according to G.V. Subbarao, researcher at the Japan International Research Center for Agricultural Sciences (JIRCAS) and first author of the new report.

“Use of wheat varieties that feature BNI opens the possibility for a more balanced and productive mix of nitrogen nutrients for wheat fields, which are currently dominated by highly-reactive nitrogen compounds that derive in large part from synthetic fertilizers and can harm the environment,” Subbarao said.

The most widely grown food crop on the planet, wheat is consumed by over 2.5 billion people in 89 countries. Nearly a fifth of the world’s nitrogen-based fertilizer is deployed each year to grow wheat but, similar to other major cereals, vegetables, and fruits, the crop takes up less than half of the nitrogen applied.

Much of the remainder is either washed away, contaminating ground waters with nitrate and contributing to algae blooms in lakes and seas, or released into the air, often as nitrous oxide, a greenhouse gas 300 times more potent than carbon dioxide.

The study team first homed in on the chromosome region associated with the strong BNI capacity in the perennial grass species Leymus racemosus and moved it from the grass, using “wide crossing” techniques, into the cultivar Chinese Spring, a wheat landrace often used in genetic studies. From there, they transferred the BNI chromosome sequence into several elite, high-yielding wheat varieties, leading to a near doubling of their BNI capacity, as measured through lab analyses of soil near their roots.

The new wheats — elite varieties from the International Maize and Wheat Improvement Center (CIMMYT) into which the BNI trait was cross-bred — greatly reduced the action of soil microbes that usually convert fertilizer and organic nitrogen substances into ecologically-harmful compounds such as nitrous oxide gas, according to Hannes Karwat, a CIMMYT post-doctoral fellow and study co-author.

“The altered soil nitrogen cycle was even reflected in the plants’ metabolism,” Karwat said, “resulting in several responses indicative of a more balanced nitrogen uptake in the plants.”

The scientists involved said BNI-converted wheats in this study also showed greater overall biomass and grain yield, with no negative effects on grain protein levels or breadmaking quality.

“This points the way for farmers to feed future wheat consumers using lower fertilizer dosages and lowering nitrous oxide emissions,” said Masahiro Kishii, a CIMMYT wheat cytogeneticist who contributed to the research. “If we can find new BNI sources, we can develop a second generation of elite wheat varieties that require even less fertilizer and that better deter nitrous oxide emissions.”

A recent PNAS paper by Subbarao and Princeton University scientist Timothy D. Searchinger mentions BNI as a technology that can help foster soils featuring a more even mix of nitrogen sources, including more of the less-chemically-reactive compound ammonium, a condition that can raise crop yields and reduce nitrous oxide emissions.

CIMMYT researcher Masahiro Kishii examines wheat plants in a greenhouse. (Photo: CIMMYT)
CIMMYT researcher Masahiro Kishii examines wheat plants in a greenhouse. (Photo: CIMMYT)

Scale out to slow global warming?

The present study comes just as the Intergovernmental Panel on Climate Change (IPCC) has released its Sixth Assessment Report, which among other things states that “… limiting human-induced global warming … requires limiting cumulative CO2 emissions … along with strong reductions in other greenhouse gas emissions.”

Globally, 30% of greenhouse gas emissions come from agriculture. BNI-enabled wheat cultivars can play an important role to reduce that footprint. Wheat-growing nations that have committed to the Paris Climate Accord, whose provisions include reducing greenhouse gas emissions 30% by 2050, could be early adopters of the BNI technology, together with China and India, the world’s top two wheat producers, according to Subbarao.

“This work has demonstrated the feasibility of introducing BNI-controlling chromosome segments into modern wheats, without disrupting their yields or quality,” said Subbarao. “To realize the technology’s full potential, we need to transfer the BNI feature into many elite varieties adapted to diverse wheat growing areas and to assess their yield in many farm settings and with varying levels of soil pH, fertilization and water use.”

A project to establish nitrogen-efficient wheat production systems in the Indo-Gangetic Plains using BNI has recently been approved by Japan and is under way, with the collaboration of JIRCAS, the Indian Council of Agricultural Research (ICAR), and the Borlaug Institute of South Asia (BISA). Under the project, BNI-converted wheat lines developed from JIRCAS-CIMMYT partnerships will be tested in India and the BNI trait transferred to popular national wheat varieties.

“The BNI-technology is also featured in Green Technology, a Japanese government policy document for moving towards a zero-carbon economy,” said Osamu Koyama, President of JIRCAS, which has also posted a note about the new PNAS study. JIRCAS and CGIAR BNI research is co-funded by the Ministry of Agriculture, Forestry and Fisheries of Japan.

“Adaptation and mitigation solutions such as BNI, which help lessen the footprint of food production systems, will play a large role in CGIAR research-for-development, as part of One CGIAR Initiatives starting in 2022,” said Bram Govaerts, CIMMYT Director General.

RELATED RESEARCH PUBLICATIONS:

Enlisting wild grass genes to combat nitrification in wheat farming: A nature-based solution

INTERVIEW OPPORTUNITIES:

Hannes Karwat – Postdoctoral Fellow, Nitrogen Use Efficiency, International Maize and Wheat Improvement Center (CIMMYT)

Masahiro Kishii – Wheat Cytogenetics, Wide Crossing, International Maize and Wheat Improvement Center (CIMMYT)

Victor Kommerell – Program Manager, CGIAR Research Program Wheat (WHEAT)

FOR MORE INFORMATION, OR TO ARRANGE INTERVIEWS, CONTACT THE MEDIA TEAM:

Rodrigo Ordóñez, Communications Manager, CIMMYT. r.ordonez@cgiar.org, +52 (55) 5804 2004 ext. 1167.

Mapping the way to lower nitrous oxide emissions

Written by Steven M on . Posted in Features.

Like many issues besetting contemporary agri-food systems, the question of nitrogen use appears to yield contradictory problems and solutions depending on where you look. Many parts of the globe are experiencing the environmental consequences of excessive and inefficient use of nitrogen fertilizers. Elsewhere nitrogen-poor soils are a hindrance to agricultural productivity.

Addressing these seemingly contradictory issues means ensuring that nitrogen is applied with maximum efficiency across the world’s croplands. Farmers should be applying as much nitrogen as can be taken up by their crops in any given agroecology. Apply more, and the excess nitrogen leads to nitrous oxide (N2O) emissions — a potent greenhouse gas (GHG) — and other environmental degradation. Apply less, and agricultural potential goes unmet. Given the twin challenges of global climate change and the projected need to increase global food production over 70% by 2050, neither scenario is desirable.

Maize and wheat agri-food systems are at the heart of this dilemma. These staple crops are critical to ensuring the food security of a growing population. They also account for around 35% of global nitrogen fertilizer usage. Tackling the problem first requires an accurate accounting of global N20 emissions from maize and wheat fields, followed by quantification of mitigation potential disaggregated by region. This is the task undertaken by a recent study published in Science of the Total Environment and co-authored by a team of researchers including scientists at the International Maize and Wheat Improvement Center (CIMMYT) and the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS).

“Spatially explicit quantification of N2O emission and mitigation potential helps identify emission hotspots and priority areas for mitigation action through better nitrogen management consistent with location-specific production and environmental goals,” says Tek Sapkota, CIMMYT’s climate scientist and review editor of the Intergovernmental Panel on Climate Change (IPCC)’s sixth assessment report.

A map shows global hotspots for nitrogen emissions linked to maize and wheat production. (Graphic: Tesfaye et al./CIMMYT)

A model approach

Researchers compared N20 emissions estimates produced using four statistical models (Tropical N2O model, CCAF-MOT, IPCC Tier-1 and IPCC Tier-11). They also compared the models’ estimates against actual emissions as recorded at 777 globally distributed points. While all four models performed relatively well vis-à-vis the empirical measurements, the IPCC Tier-II estimates showed a better relationship to the measured data across both maize and wheat fields and low- and high-emissions scenarios.

Researchers found that, for both maize and wheat, emissions were highest in East and South Asia, as well as parts of Europe and North America. For maize, parts of South America also appeared to be emissions hotspots. In Asia, China, India, Indonesia and the Philippines were major emitters for both crops. Researchers also observed that China, along with Egypt, Pakistan and northern India have the highest excess nitrogen application (i.e., nitrogen in excess of what can be productively taken up by crops).

Trimming the excess

Specifically identifying hotspots of excess nitrogen application is important, as they represent promising areas to target for emissions reductions. For a given region, the volume of emissions may be a factor simply of large areas under maize or wheat cultivation coupled with of high levels of nitrogen usage. However, farmers in such regions may be not have much room to reduce nitrogen application without affecting yield. And reducing the area under cultivation may not be desirable or viable. Where the rate of excess nitrogen application is high, however, reducing the rate of application and increasing the efficiency of nitrogen use is a win-win.

A farmer in Ethiopia prepares to spread UREA fertilizer by hand in his field after the sowing of wheat. (Photo: CIMMYT)

The researchers estimate that a nitrous oxide emission reduction potential of 25-75% can be achieved through various management practices, such as the 4Rs, which stand for the right source, right timing, right placement and right application rate. Not only would such a reduction drastically reduce N2O emissions and lessen other environmental impacts of maize and wheat production, it would represent a significant cost savings to farmers. Improved efficiency in nitrogen application can also have positive effects on crop yield.

“Promoting integrated nitrogen management approaches through the right policies, institutional supports and good extension systems is essential to improving the use efficiency of nitrogen in order to meet food security, climate action and other sustainable development goals,” says Sapkota.

Kindie Tesfaye, a CIMMYT scientist and one of the authors of the paper, adds, “The policy importance of the study is that the estimated mitigation potentials from global maize and wheat fields are useful for hotspot countries to target fertilizer and crop management as one of the mitigation options in their Nationally Determined Contributions (NDCs) to the United Nations Framework Convention on Climate Change (UNFCCC).”

Smallholder farmer Sita Kumari holds fertilizer in her hands. (Photo: C. de Bode/CGIAR)

On-farm nitrogen management practices have global reverberations

Written by Rodrigo Ordóñez on . Posted in Press releases.

Smallholder farmer Sita Kumari holds fertilizer in her hands. (Photo: C. de Bode/CGIAR)
Smallholder farmer Sita Kumari holds fertilizer in her hands. (Photo: C. de Bode/CGIAR)

An international team of scientists has strengthened our understanding of how better fertilizer management could help minimize nitrous oxide (N2O) emissions while still achieving high crop yields in the new publication: Meta-analysis of yield and nitrous oxide outcomes for nitrogen management in agriculture. This research was conducted through a meta-analysis, where the results of multiple scientific studies were statistically combined.

To meet the world’s growing demand for food, farmers need fertile soil. Nitrogen, an essential element in plant fertilizer, can have extremely deleterious effects on the environment when not managed effectively. Numerous studies have confirmed that improving nitrogen use in agriculture is key to securing a food secure future and environmental sustainability.

“Society needs nuanced strategies based upon tailored nutrient management approaches that keep nitrogen balances within safe limits,” said Tai M Maaz, researcher at University of Hawaii at Manoa and lead author of the study.

When farmers apply nitrogen fertilizer to their crop, typically only 30-40% of it is taken up by the plant and the rest is lost the the environment. One byproduct is  nitrous oxide (N2O), one of the most potent greenhouse gases in the atmosphere. Global agriculture is a major contributor of greenhouse gas emissions, especially those derived from nitrous oxide emissions.

Although farmers are now commonly told to practice fertilizer rate reduction, or simply put, to apply less fertilizer, there are cases where that strategy is either not possible or not advisable.

Alternative predictors of emissions

The study found that output indicators such as partial nitrogen balance (PNB), an indicator for the amount of nitrogen prone to loss, and partial factor productivity (PFP), a measure of input-use efficiency, predicted nitrous oxide emissions as well as or better than the application rate alone. This means that in some cases, where nitrogen rate reduction is not possible, nitrous oxide emission can still be reduced by increasing yield through implementation of improved fertilizer management practices, such as the “4Rs:” right source, right timing, right placement and right application rate.

Tek B Sapkota, climate scientist at the International Maize and Wheat Improvement Center (CIMMYT) and co-author of the study, emphasized that “rate reduction is still important in the cropping systems where the current level of nitrogen application is excessively high. But, when comparing the systems at the same nitrogen application rates, nitrous oxide emission can be reduced by increasing yield.”

“The 4R nutrient management practices must be tailored to specific regions to help close yield gaps and maintain environmental sustainability: the win-win scenario. The future will require public and private institutions working together to disseminate such nutrient management information for specific cropping systems in specific geographies,” said Sapkota, who is also a review editor of the Intergovernmental Panel on Climate Change (IPCC) sixth assessment report.

The article was a collaborative effort from the International Maize and Wheat Improvement Center (CIMMYT), the University of Hawaii, the Environmental Defense Fund, Plant Nutrition Canada and the African Plant Nutrition Institute. It was funded by the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS).

Read the full study:
Meta-analysis of yield and nitrous oxide outcomes for nitrogen management in agriculture

 

FOR MORE INFORMATION, OR TO ARRANGE INTERVIEWS, CONTACT:

Marcia MacNeil, Communications Officer, CGIAR Research Program on Wheat, CIMMYT. m.macneil@cgiar.org

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

Digital nutrient management tool reduces emissions, improves crop yields and boosts farmers’ profits

Written by Alison Doody on . Posted in News.

A farmer in the Ara district, in India's Bihar state, applies NPK fertilizer, composed primarily of nitrogen, phosphorus and potassium. (Photo: Dakshinamurthy Vedachalam/CIMMYT)
A farmer in the Ara district, in India’s Bihar state, applies NPK fertilizer, composed primarily of nitrogen, phosphorus and potassium. (Photo: Dakshinamurthy Vedachalam/CIMMYT)

An international team of scientists, led by the International Maize and Wheat Improvement Center (CIMMYT), has demonstrated how better nutrient management using digital tools, such as the Nutrient Expert decision support tool, can boost rice and wheat productivity and increase farmers’ income while reducing chemical fertilizer use and greenhouse gas emissions.

Reported today in Nature Scientific Reports, the results show how the farmer-friendly digital nutrient management tool can play a key role in fighting climate change while closing the yield gap and boosting farmers’ profits.

The researchers tested the Nutrient Expert decision tool against typical farmer fertilization practices extensively using approximately 1600 side-by side comparison trials in rice and wheat fields across the Indo-Gangetic Plains of India.

The study found that Nutrient Expert-based recommendations lowered global warming potential by 12-20% in wheat and by around 2.5% in rice, compared to conventional farmers’ fertilization practices. Over 80% of farmers were also able to increase their crop yields and incomes using the tool.

Agriculture is the second largest contributor of greenhouse gas emissions in India. To tackle these emissions, crop scientists have been working on new ways to make farming more nutrient- and energy-efficient. Of the many technologies available, improving nutrient-use-efficiency through balanced fertilizer application — which in turn reduces excess fertilizer application — is key to ensuring food security while at the same time contributing to the UN’s Sustainable Development Goals on climate change.

The work was carried out by CIMMYT in collaboration with farmers, and funded by the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS), the CGIAR Research Program on Wheat (WHEAT), and the Indian Council of Agricultural Research (ICAR). Scientists from the Borlaug Institute for South Asia (BISA), the International Rice Research Institute (IRRI), the Alliance of Bioversity International and CIAT, and the former International Plant Nutrition Institute (IPNI) also contributed to this study.

Researchers tested the Nutrient Expert decision tool against typical farmer fertilization practices extensively using approximately 1600 side-by side comparison trials in rice and wheat fields across the Indo-Gangetic Plains of India (Graphic: CIMMYT).
Researchers tested the Nutrient Expert decision tool against typical farmer fertilization practices extensively using approximately 1600 side-by side comparison trials in rice and wheat fields across the Indo-Gangetic Plains of India (Graphic: CIMMYT).

Precise recommendations

Nutrient Expert, which was launched back in 2013, works by analysing growing conditions, natural nutrients in the soil, and even leftover nutrients from previous crops to provide tailored fertilizer recommendations directly to farmers phones. The tool also complements the Government of India’s Soil Health Cards for balanced and precise nutrient recommendations in smallholder farmers’ fields.

Each farmer’s field is different, which is why blanket fertilizer recommendations aren’t always effective in producing better yields. By using nutrient management tools such as Nutrient Expert, farmers can obtain fertilizer recommendations specific to the conditions of their field as well as their economic resources and thus avoid under-fertilizing or over-fertilizing their fields.

“While efficient nutrient management in croplands is widely recognized as one of the solutions to addressing the global challenge of supporting food security in a growing global population while safeguarding planetary health, Nutrient Expert could be an important tool to implement such efficient nutrient management digitally under smallholder production systems,” said Tek Sapkota, CIMMYT climate scientist and first author of the study.

Sapkota also argues that adoption of the Nutrient Expert tool in rice-wheat systems of India alone could provide almost 14 million tonnes (Mt) of extra grain with 1.4 Mt less nitrogen fertilizer use, and a reduction of 5.3 Mt of carbon (CO2) emissions per year over current practices.

However, technological innovation alone will not achieve these positive outcomes.

“Given the magnitude of potential implications in terms of increasing yield, reducing fertilizer consumption and greenhouse gas emissions, governments need to scale-out Nutrient Expert-based fertilizer management through proper policy and institutional arrangements, especially for making efficient use of the nearly 200 million Soil Health Cards that were issued to farmers as part of the Soil Health mission of the Government of India,” said ML Jat, CIMMYT principal scientist and co-author of the study.

Read the study:
Crop nutrient management using Nutrient Expert improves yield, increases farmers’ income and reduces greenhouse gas emissions.