Visit between Bill Gates and DFID head Alok Sharma featured demonstration of MARPLE mobile rust-testing lab
New £38 million funding from the Department for International Development (DFID, or UK aid), with additional funding from the Bill & Melinda Gates Foundation, will allow scientists to research cutting-edge technology to protect crops from pests and diseases and produce new varieties that are climate-resilient.
The joint funding, which was announced on Monday October 7, will directly contribute to securing global food security against pest and disease threats, climate change and natural resource scarcity. It will also reduce poverty in sub-Saharan Africa and South Asia by improving agricultural productivity of smallholder farmers.
The partnership will support biotechnologies to enable crops to convert sunlight and carbon dioxide more efficiently to promote higher yields, tools and methods to reduce the impact of root crop diseases in West Africa, and work to harness naturally occurring biological nitrogen fixation processes to improve crops’ nitrogen uptake and increase yields while reducing fertilizer use among smallholder farmers in Africa.
Early last year DFID also announced funding for CGIAR to help scientists identify specific genes in crops related to improved nutrition, faster growth and disease and climate-resilience. Their work will help up to 100 million African farmers and their families lift themselves out of poverty.
Published in Science, the article provides evidence for national policies that block stubble burning and promote no-till mechanization to manage crop residues.
This story by Mike Listman was originally posted on the website of the International Maize and Wheat Improvement Center (CIMMYT).
The new study compares the costs and benefits of 10 distinct land preparation and sowing practices for northern India’s rice-wheat cropping rotations, which are spread across more than 4 million hectares. The direct seeding of wheat into unplowed soil and shredded rice residues was the best option — it raises farmers’ profits through higher yields and savings in labor, fuel, and machinery costs.
The study, conducted by a global team of eminent agriculture and environmental scientists, was led by researchers from The Nature Conservancy, the International Maize and Wheat Improvement Center (CIMMYT), the Indian Council of Agricultural Research (ICAR), the Borlaug Institute for South Asia (BISA) and the University of Minnesota.
A new economic study in the journal Science shows that thousands of farmers in northern India could increase their profits if they stop burning their rice straw and adopt no-till practices to grow wheat. Alternative farming practices could also cut farmers’ greenhouse gas emissions from on-farm activities by as much as 78% and help lower air pollution in cities like New Delhi.
A burning issue
To quickly and cheaply clear their fields to sow wheat each year, farmers in northern India burn an estimated 23 million tons of straw from their rice harvests. That enormous mass of straw, if packed into 20-kilogram 38-centimeter-high bales and piled on top of each other, would reach a height of over 430,000 kilometers — about 1.1 times the distance to the moon.
Regulations are in place in India to reduce agricultural fires but burning continues because of implementation challenges and lack of clarity about the profitability of alternate, no-burn farming.
Farmers have alternatives, the study shows. To sow wheat directly without plowing or burning rice straw, farmers need to purchase or rent a tractor-mounted implement known as the “Happy Seeder,” as well as attach straw shredders to their rice harvesters. Leaving straw on the soil as a mulch helps capture and retain moisture and also improves soil quality, according to M.L. Jat, CIMMYT Principal Scientist, cropping systems specialist and a co-author of the study.
The Science study demonstrates that it is possible to reduce air pollution and greenhouse gas emissions in a way that is profitable to farmers and scalable.
The paper shows that Happy Seeder-based systems are on average 10%–20% more profitable than straw burning options.
“Our study dovetails with 2018 policies put in place by the government of India to stop farmers from burning, which includes a US$166 million subsidy to promote mechanization to manage crop residues within fields,” said Priya Shyamsundar, Lead Economist, Global Science, of The Nature Conservancy and first author of the study.
Shyamsundar noted that relatively few Indian farmers currently sow their wheat using the Happy Seeder but manufacturing of the Seeder had increased in recent years. “Less than a quarter of the total subsidy would pay for widespread adoption of the Happy Seeder, if aided by government and NGO support to build farmer awareness and impede burning.”
“With a rising population of 1.6 billion people, South Asia hosts 40% of the world’s poor and malnourished on just 2.4% of its land,” said Jat, who recently received India’s prestigious Rafi Ahmed Kidwai Award for outstanding and impact-oriented research contributions in natural resource management and agricultural engineering. “Better practices can help farmers adapt to warmer winters and extreme, erratic weather events such as droughts and floods, which are having a terrible impact on agriculture and livelihoods. In addition, India’s efforts to transition to more sustainable, less polluting farming practices can provide lessons for other countries facing similar risks and challenges.”
In November 2017, more than 4,000 schools closed in Delhi due to seasonal smog. This smog increases during October and November when fields are burned. It causes major transportation disruptions and poses health risks across northern India, including Delhi, a city of more than 18 million people.
Some of these problems can be resolved by the use of direct sowing technologies in northwestern India.
“Within one year of our dedicated action using about US$75 million under the Central Sector Scheme on ‘Promotion of agriculture mechanization for in-situ management of crop residue in the states of Punjab, Haryana, Uttar Pradesh and NCT of Delhi,’ we could reach 0.8 million hectares of adoption of Happy Seeder/zero tillage technology in the northwestern states of India,” said Trilochan Mohapatra, director general of the Indian Council of Agricultural Research (ICAR). “Considering the findings of the Science article as well as reports from thousands of participatory validation trials, our efforts have resulted in an additional direct farmer benefit of US$131 million, compared to a burning option,” explained Mohapatra, who is also secretary of India’s Department of Agricultural Research and Education.
This research was supported by the Susan and Craig McCaw Foundation, the Institute on the Environment at the University of Minnesota, the CGIAR Research Program on Wheat (WHEAT), and the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS). The Happy Seeder was originally developed through a project from the Australian Centre for International Agricultural Research (ACIAR).
For more information, or to arrange interviews with the researchers, please contact:
International gathering highlights cutting edge efforts to improve yields, nutrition, and climate change resilience of a globally vital staple food
by Julie Mollins
As many regions worldwide baked under some of the most persistent
heatwaves on record, scientists at a major conference in Canada shared data on
the impact of spiraling temperatures on wheat.
In the Sonora desert in northwestern Mexico, nighttime temperatures varied 4.4 degrees Celsius between 1981 and 2018, research from the International Maize and Wheat Improvement Center (CIMMYT) shows. Across the world in Siberia, nighttime temperatures rose 2 degrees Celsius between 1988 and 2015, according to Vladimir Shamanin, a professor at Russia’s Omsk State Agrarian University who conducts research with the Kazakhstan-Siberia Network on Spring Wheat Improvement.
“Although field trials across some of the hottest wheat growing environments worldwide have demonstrated that yield losses are in general associated with an increase in average temperatures, minimum temperatures at night – not maximum daytime temperatures –are actually determining the yield loss,” said Gemma Molero, the wheat physiologist at CIMMYT who conducted the research in Sonora, in collaboration with colleague Ivan Ortiz-Monasterio.
“Of the water taken up by the roots, 95% is lost from leaves via transpiration and from this, an average of 12% of the water is lost during the night. One focus of genetic improvement for yield and water-use efficiency for the plant should be to identify traits for adaptation to higher night temperatures,” Molero said, adding that nocturnal transpiration may lead to reductions of up to 50% of available soil moisture in some regions.
The Intergovernmental Panel on Climate Change (IPCC) reported in October that temperatures may become an average of 1.5 degrees Celsius warmer in the next 11 years. A new IPCC analysis on climate change and land use due for release this week, urges a shift toward reducing meat in diets to help reduce agriculture-related emissions from livestock. Diets could be built around coarse grains, pulses, nuts and seeds instead.
Scientists attending the International Wheat Congress in Saskatoon, the city at the heart of Canada’s western wheat growing province of Saskatchewan, agreed that a major challenge is to develop more nutritious wheat varieties that can produce bigger yields in hotter temperatures.
As a staple crop, wheat provides 20% of all human calories consumed worldwide. It is the main source of protein for 2.5 billion people in the Global South. Crop system modeler Senthold Asseng, a professor at the University of Florida and a member of the International Wheat Yield Partnership, was involved in an extensive study in China, India, France, Russia and the United States, which demonstrated that for each degree Celsius in temperature increase, yields decline by 6%, putting food security at risk.
Wheat yields in South Asia could be cut in half due to chronically high temperatures, Molero said. Research conducted by the University of New South Wales, published in Environmental Research Letters also demonstrates that changes in climate accounted for 20 to 49% of yield fluctuations in various crops, including spring wheat. Hot and cold temperature extremes, drought and heavy precipitation accounted for 18 to 4% of the variations.
At CIMMYT, wheat breeders advocate a comprehensive
approach that combines conventional, physiological and molecular breeding
techniques, as well as good crop management practices that can ameliorate heat
shocks. New breeding technologies are making use of wheat landraces and wild
grass relatives to add stress adaptive traits into modern wheat – innovative approaches that have led to new
heat tolerant varieties being grown by farmers in warmer regions of Pakistan,
“HeDWIC is a pre-breeding program that aims to deliver genetically diverse advanced
lines through use of shared germplasm and other technologies,” Reynolds said in
Saskatoon. “It’s a knowledge-sharing and training mechanism, and a platform to deliver proofs
of concept related to new technologies for adapting wheat to a range of heat
and drought stress profiles.”
Aims include reaching agreement
across borders and institutions on the most promising research areas to achieve
climate resilience, arranging trait research into a rational framework, facilitating
and developing a bioinformatics cyber-infrastructure, he said, adding that
attracting multi-year funding for international collaborations remains a
area of climate research at CIMMYT involves the development of an affordable
alternative to the use of nitrogen fertilizers to reduce planet-warming
greenhouse gas emissions. In certain plants, a trait known as biological
nitrification inhibition (BNI) allows them to suppress the loss of nitrogen
from the soil, improving the efficiency of nitrogen uptake and use by
themselves and other plants.
“Every year, nearly a fifth of the world’s fertilizer is used to grow wheat, yet the crop only uses about 30% of the nitrogen applied, in terms of biomass and harvested grains,” said Victor Kommerell, program manager for the multi-partner CGIAR Research Programs (CRP) on Wheat and Maize led by the International Maize and Wheat Improvement Center.
has the potential to turn wheat into a highly nitrogen-efficient crop: farmers
could save money on fertilizers, and nitrous oxide emissions from wheat farming
could be reduced by 30%.”
Excluding changes in land use such as deforestation, annual greenhouse gas emissions from agriculture each year are equivalent to 11% of all emissions from human activities. About 70% of nitrogen applied to crops in fertilizers is either washed away or becomes nitrous oxide, a greenhouse gas 300 times more potent than carbon dioxide, according to Guntur Subbarao, a principal scientist with JIRCAS.
To exploit this roots-based characteristic,
breeders would have to breed this trait into plants, said Searchinger, who
presented key findings of the report in Saskatoon, adding that governments and
research agencies should increase research funding.
Other climate change mitigation efforts must
include revitalizing degraded soils, which affect about a quarter of the
planet’s cropland, to help boost crop yields. Conservation agriculture
techniques involve retaining crop residues on fields instead of burning and
clearing. Direct seeding into soil-with-residue and agroforestry also can play
a key role.
How can space technology help improve maize and wheat production? CIMMYT joined a group of international data users in a recent project to find out.
In 2017, a call for proposals from Copernicus Climate Change Service Sectoral Information Systems led the International Maize and Wheat Improvement Center (CIMMYT to collaborate with Wageningen University, the European Space Agency (ESA), and other research and meteorological organizations to develop practical applications in agricultural and food security for satellite-sourced weather data.
The project, which recently ended, opened the door to a wide variety of potential uses for this highly detailed data.
ESA collects extremely granular data on weather, churned out at an hourly rate. CIMMYT researchers, including Foresight Specialist Gideon Kruseman, reviewed this data stream, which generates 22 variables of daily and sub-daily weather data at a 30-kilometerlevel of accuracy, and evaluated how it could help generate agriculture-specific weather and climate data sets.
“For most people, the reaction would be, ‘What do we do with this?’ Kruseman said. “For us, this is a gold mine.”
For example, wind speed — an important variable collected by ESA satellites — is key for analyzing plant evaporation rates, and thus their drought tolerance. In addition, to date, information is available on ideal ago-climatic zones for various crop varieties, but there is no data on the actual weather conditions during a particular growing season for most sites.
By incorporating the information from the data sets into field trial data, CIMMYT researchers can specifically analyze maize and wheat cropping systems on a larger scale and create crop models with higher precision, meaning that much more accurate information can be generated from the trials of different crop varieties.
The currently available historic daily and sub-daily data, dating back to 1979, will allow CIMMYT and its partners to conduct “genotype by environment (GxE)” interaction analysis in much higher detail. For example, it will allow researchers to detect side effects related to droughts and heat waves and the tolerance of maize and wheat lines to those stresses. This will help breeders create specific crop varieties for farmers in environments where the impact of climate change is predicted to be more apparent in the near future.
“The data from this project has great potential fix this gap in information so that farmers can eventually receive more targeted assistance,” said Kruseman.
These ideas are just the beginning of the agricultural research and food security potential of the ESA data. For example, Kruseman would like to link the data to household surveys to review the relationship between the weather farmers experience and the farming decisions they make.
By the end of 2019, the data will live on an open access, user-friendly database. Eventually, space agency-sourced weather data from as far back as 1951 to as recent as five days ago will be available to researchers and weather enthusiasts alike.
Already CIMMYT scientists are using this data to understand the potential of a promising wheat line, for seasonal forecasting, to analyze gene-bank accessions and for a statistical analysis of maize trials, with many more high-impact applications expected in the future.
Crop scientists refute the flawed findings of a study questioning climate resilience in modern wheat breeding.
This article by Marcia MacNeil was originally posted on May 28, 2019 on cimmyt.org.
In early 2019, an article published by European climate researchers in the Proceedings of the National Academy of Science (PNAS) journal questioned the climate resilience of modern wheat varieties. The article suggested that modern wheat varieties showed reduced climate resilience as a direct result of modern breeding methods and practices, a claim that researchers at the International Maize and Wheat Improvement Center (CIMMYT) vehemently rebuke
In a rebuttal letter published in the June issue of PNAS a group of scientists, including CIMMYT’s Susanne Dreisigacker and Sarah Hearne, strongly contradict the finding that breeding has reduced climate resilience in European wheat, citing significant flaws in the authors’ methodology, data analyses and interpretation.
“This article discredits European plant breeders and wheat breeders in general, who have been working over many decades to produce a wide range of regionally adapted, stable varieties which perform well under a broad range of climate change conditions,” said CIMMYT wheat molecular geneticist Susanne Dreisigacker.
Among other flaws, they found a number of omissions and inconsistencies.
The article shows a lack of understanding of commonly used terms and principles of breeding theory, criticizing newer wheat varieties for demonstrating a decrease in “climatic response diversity.” Less diversity in wheat response — that is, more stable yields despite the influence of climate change — is a benefit, not a threat, to farmers.
The article authors contradict the common knowledge among farmers and plant breeders that new elite wheat varieties are generally more productive than older varieties; new cultivars are only approved if they show added value in direct comparison to existing varieties.
The article’s claim of long-term losses of climate resilience in “European wheat” is unsubstantiated. The authors extensively used data from three small countries — the Czech Republic, Denmark and Slovakia — which contribute less than five percent of Europe’s wheat supply. Three of the five most important wheat producers in Europe — Russia, Ukraine and the United Kingdom — were not accounted for in the analysis.
The authors failed to report the actual wheat yields in their study, neglected to publish the underlying data with the manuscript and have up to now declined requests to make the data available.
Europe is one of the world’s major wheat producers and threats to its wheat production due to climate change would have serious consequences for world’s food security. Luckily, say the scientists who published the rebuttal letter, this fear is unfounded.
“Wheat producers and bread consumers around the world will be relieved to learn that breeders have not ignored climate change after all,” said letter lead-author Rod Snowdon, from the Department of Plant Breeding at Justus Liebig University of Giessen, Germany.
The full rebuttal letter by 19 international plant breeders, agronomists and scientists, is available on the PNAS site and reprinted in its entirety below.
Reduced response diversity does not negatively impact wheat climate resilience
Kahiluoto et al. (1) assert that climate resilience in European wheat has declined due to current breeding practices. To support this alarming claim, the authors report yield variance data indicating increasingly homogeneous responses to climatic fluctuations in modern wheat cultivars. They evaluated “response diversity,” a measure of responses to environmental change among different species jointly contributing to ecosystem functions (2). We question the suitability of this measure to describe agronomic fitness in single-cultivar wheat cropping systems. Conclusions are made about “long-term trends,” which in fact span data from barely a decade, corresponding to the duration of a single wheat breeding cycle. The authors furthermore acknowledge increasing climate variability during the study period, confounding their analysis of climate response in the same time span.
The underlying data are not published with the manuscript. Thus, the assertion that there is “no inherent trade-off between yield potential and diversity in weather responses” (1) cannot be verified. Inexplicably, the analysis and conclusions ignore absolute yields, which increase over time through breeding (3–6). Furthermore, incompatible data from completely different ecogeographical forms and species of wheat are apparently considered together, and the dataset is strongly biased toward a few small countries with minimal wheat production and narrow agroclimatic gradients.
The study assumes that increased response diversity among different cultivars is associated with yield stability. In contrast, the common, agronomic definition of yield stability refers to the ability of a single cultivar to stably perform well in diverse environments, without excessive responses to fluctuating conditions. Response diversity measures that ignore absolute yield do not support statements about food security or financial returns to farmers.
Cultivar yield potential, stability, and adaptation are enhanced by multienvironment selection over long breeding time frames, encompassing climate fluctuations and a multitude of other relevant environmental variables. Translation to on-farm productivity is promoted by national registration trials and extensive, postregistration regional variety trials in diverse environments. The unsurprising conclusion that planting multiple cultivars enhances overall production stability mirrors longstanding farming recommendations and practice (7). The availability of robust performance data from a broad range of high-performing cultivars enables European farmers to manage their production and income risks.
Kahiluoto et al. (1) speculate about “genetic erosion” of modern cultivars due to a “lack of incentives for breeders to introduce divergent material.” To substantiate these claims, the authors cite inadequate genetic data from non-European durum wheat (8), while explicitly dismissing clearly opposing findings about genetic diversity in European bread wheat (9). Short-term reductions in response diversity in five countries were misleadingly reported as a “long-term decline” in climate resilience in “most European countries,” although six out of seven countries with sufficient data showed no long-term decline. The article from Kahiluoto et al. and the misrepresentation of its results distorts decades of rigorous, successful breeding for yield potential and stability in European wheat and misleads farmers with pronouncements that are not supported by relevant data.
1 H. Kahiluoto et al., Decline in climate resilience of European wheat. Proc. Natl. Acad. Sci. USA 116, 123–128 (2019).
2 T. Elmqvist et al., Response diversity, ecosystem change, and resilience. Front. Ecol. Environ. 1, 488–494 (2003).
3 S. De Schepper, M. De Loose, E. Van Bockstaele, P. Debergh, Ploidy analysis of azalea flower colour sports. Meded. Rijksuniv. Gent. Fak. Landbouwkd. Toegep. Biol. Wet. 66, 447–449 (2001).
4 I. Mackay et al., Reanalyses of the historical series of UK variety trials to quantify the contributions of genetic and environmental factors to trends and variability in yield over time. Theor. Appl. Genet. 122, 225–238 (2011).
5 F. Laidig et al., Breeding progress, environmental variation and correlation of winter wheat yield and quality traits in German official variety trials and on-farm during 1983-2014. Theor. Appl. Genet. 130, 223–245 (2017).
6 T. Würschum, W. L. Leiser, S. M. Langer, M. R. Tucker, C. F. H. Longin, Phenotypic and genetic analysis of spike and kernel characteristics in wheat reveals long-term genetic trends of grain yield components. Theor. Appl. Genet. 131, 2071–2084 (2018).
7 P. Annicchiarico, “Genotype x environment interactions: Challenges and opportunities for plant breeding and cultivar recommendations.” (Food and Agriculture 201 Organisation of the United Nations, Rome, Italy, 2002), FAO Plant Production and Protection Paper 174.
8 F. Henkrar et al., Genetic diversity reduction in improved durum wheat cultivars of Morocco as revealed by microsatellite markers. Sci. Agric. 73, 134–141 (2016).
9 M. van de Wouw, T. van Hintum, C. Kik, R. van Treuren, B. Visser, Genetic diversity trends in twentieth century crop cultivars: A meta analysis. Theor. Appl. Genet. 120, 1241–1252 (2010).
By Md. Ashraful Alam, Sultana Jahan and M. Shahidul Haque Khan
Bangladesh farmer Raju Sarder rests his sickle and sits happily on a recently acquired reaper. Photo: iDE/Md. Ikram Hossain
A man in his early 20s walked the winding roads of Sajiara village, Dumuria upazila, Khulna District in Bangladesh. His head hanging low, he noticed darkness slowly descending and then looked up to see an old farmer wrapping up his own daily activities. With traditional tools in hand, the farmer looked exhausted. The young man, Raju Sarder, considered that there had to be a better way to farm while alleviating his drudgery and that of others in the community.
Determined to act, Raju set out to meet Department of Agricultural Extension (DAE) officials the very next day. They informed him about the Mechanization and Irrigation project of the Cereal Systems Initiative for South Asia (CSISA MI). They also introduced him to the project’s most popular technologies, namely the power tiller operated seeder, reaper and axial flow pumps, all of which reduce labor costs and increase farming efficiency.
Raju found the reaper to be the most interesting and relevant for his work, and contacted CSISA SI to acquire one.
The first challenge he encountered was the cost — $1,970 — which as a small-scale farmer he could not afford. CSISA MI field staff assured him that his ambitions were not nipped in the bud and guided him in obtaining a government subsidy and a loan of $1,070 from TMSS, one of CSISA MI’s micro financing partners. Following operator and maintenance training from CSISA MI, Raju began providing reaping services to local smallholder rice and wheat farmers.
He noticed immediately that he did not have to exert himself as much as before but actually gained time for leisure and his production costs dwindled. Most remarkably, for reaping 24 hectares Raju generated a profit of $1,806; a staggering 15 times greater than what he could obtain using traditional, manual methods and enough to pay back his loan in the first season.
“There was a time when I was unsure whether I would be able to afford my next meal,” said Raju, “but it’s all different now because profits are pouring in thanks to the reaper.”
As a result of the project and farmers’ interest, field labor in Raju’s community is also being transformed. Gone are the days when farmers toiled from dawn to dusk bending and squatting to cut the rice and wheat with rustic sickles. Laborious traditional methods are being replaced by modern and effective mechanization.
Through projects such as CSISA MI, CIMMYT is helping farmers like Raju to become young entrepreneurs with a bright future. Once poor laborers disaffected and treated badly in their own society, these youths now walk with dignity and pride as significant contributors to local economic development.
In breakthrough science using recent advances in sequencing, the International Wheat Genome Sequencing Consortium presents an annotated reference genome with a detailed analysis of gene content among subgenomes and the structural organization for all the chromosomes. To read article in Science, click here.
This blast-infected wheat spike contains no grain, only chaff. Photo: CIMMYT files
By Gideon Kruseman and Mike Listman
A spatial mapping and ex ante studyregarding the risk and potential spread in South Asia of wheat blast, a mysterious and deadly disease from the Americas that unexpectedly infected wheat in southwestern Bangladesh in 2016, identified 7 million hectares of wheat cropping areas in Bangladesh, India, and Pakistan whose agro-climatic conditions resemble those of the Bangladesh outbreak zone.
The study shows that, under a conservative scenario of 5-10% wheat blast production damage in a single season in those areas, wheat grain losses would amount to from 0.89 to 1.77 million tons, worth between $180 and $350 million. This would strain the region’s already fragile food security and force up wheat imports and prices, according to Khondoker Abdul Mottaleb, first author of the study.
“Climate change and related changes in weather patterns, together with continuing globalization, expose wheat crops to increased risks from pathogens that are sometimes transported over long distances,” said Mottaleb.
Foresight research at the International Maize and Wheat Improvement Center (CIMMYT) has focused on new diseases and pests that have emerged or spread in recent decades, threatening global food safety and security. For wheat these include Ug99 and other new strains of stem rust, the movement of stripe rust into new areas, and the sudden appearance in Bangladesh of wheat blast, which had previously been limited to South America.
“As early as 2011, CIMMYT researchers had warned that wheat blast could spread to new areas, including South Asia,” said Kai Sonder, who manages CIMMYT’s geographic information systems lab and was a co-author on the current study, referring to a 2011 notepublished by the American Pathological Society. “Now that forecast has come true.”
CIMMYT has played a pivotal role in global efforts to study and control blast, with funding from the Australian Center for International Agricultural Research (ACIAR), the CGIAR Research Program on Wheat (WHEAT), the Indian Council of Agriculture Research (ICAR), and the United States Agency for International Development (USAID).
Iván Ortíz-Monasterio, expert on sustainable intensification and wheat crop management at the International Maize and Wheat Improvement Center (CIMMYT), recently took part in a study detailing the detriments of excess fertilizeruse and the benefits of more precise dosages.
In the following interview, he discusses the overuse of nitrogen fertilizer and related consequences, his experience with farmers, and his outlook for the future. According to Ortíz-Monasterio and study co-authors, research on wheat in the Yaqui Valley, state of Sonora, northwestern Mexico, and home to CIMMYT’s Norman E. Borlaug Experiment Station (CENEB), has direct implications for wheat crop management worldwide.
“The Yaqui Valley is agro-climatically representative of areas where 40 percent of the world’s wheat is grown, including places like the Indo-Gangetic Plains of India and Pakistan, the Nile Delta in Egypt, and the wheat lands of China,” said Ortíz-Monasterio.
A key finding of the new publication was that, after a certain point, applying more nitrogen fertilizer does not increase yields, making excessive applications essentially a drain on farmers’ resources. Why then do farmers continue to apply more fertilizer than the crop needs?
Well there is a risk, if you under-apply N fertilizer, your yield goes down. Farmers are afraid that the yield will be lower and that their profit will be lower. The cost of under-applying for them is greater than the cost of over-applying, because they’re not paying all the costs of over applying. Those costs include the environmental impacts associated with greenhouse gas emissions, at a regional scale in the case of the Yaqui Valley because of nitrification of the Sea of Cortez, and at a local level due to contamination of the water table. All these costs are passed on to society. If we passed them on to farmers, then they would be more concerned about over-applying nitrogen fertilizers.
-Do you think farmers becoming more concerned is something that could happen?
Well there are starting to be more regulations in Europe. In the UK, farmers cannot apply any nitrogen before or at sowing; they can apply fertilizer only once the plant is about 15 centimeters tall. In other parts of Europe, like Germany, farmers cannot apply more than 150 kilograms of nitrogen on wheat, so it’s happening in other parts of the world. The government of Mexico and others are making commitments to reduce nitrous oxide emissions by 20 percent by 2030 and, in the case of agriculture, the main source of nitrous oxide is nitrogen fertilizer. To meet such commitments, governments will have to take policy action so, yes; I think there’s a good chance something will happen.
There are technologies that can help farmers know precisely when to apply fertilizer and how much, for optimal crop yield and nitrogen use. Do many farmers use them? Why or why not?
Something interesting to me is what’s happening right now. For the last 10 years, we’ve been working with Yaqui Valley farmers to test and promote hand-held sensors and hiring farm advisors paid with government money who provide this service free to farmers, and adoption was high. Then the government removed the subsidy, expecting farmers to begin covering the cost, but
farmers didn’t want to pay for it.
Then a company that uses drones approached me and other researchers in the region and requested our help to convert wheat crop sensor data obtained using airborne drones to recommended fertilizer dosages. We agreed and, in their first year of operation, farmers growing wheat on 1,000 hectares paid for this service. I don’t know what it is—maybe seeing a colorful map is more sexy—but farmers seem to be willing to pay if you fly a drone to collect the data instead of having a farm advisor walk over the field. But it’s great! In the past we relied on the government to transfer the technology and now we have this great example of a private-public partnership, where a company is helping to transfer the technology and making a profit, so that will make it sustainable. I’m very excited about that!
Does CIMMYT have a plan to increase adoption of these technologies?
A CIMMYT technician uses a hand-held sensor to measure NDVI (normalized difference vegetative index) in a wheat field at the center’s CENEB experiment station near Ciudad Obregón, Sonora, northern Mexico. Photo: CIMMYT.
We’re not married to one technology, but need to work with all of them. You know we started with Greekseeker, which is a ground-based sensor, and now we’re also working with drones, with manned airplanes mounted with cameras, and even satellite images. So, there are four different ways to collect the data, and we’ve seen that the Greenseeker results correlate well with all of them, so the technology we developed originally for Greenseeker can be used with all the other platforms.
Are you optimistic that farmers can shift their perceptions in this area and significantly reduce their nitrogen use?
I think we’re moving in that direction, but slowly. We need policy help from the government. Officials need to give some type of incentive to farmers to use the technology, because when farmers do something different they see it as a risk. To compensate for that risk, give them a carrot, rather than a stick, and I think that will help us move the technology faster.
A wheat farm family from the Yaqui Valley, northwestern Mexico. Photo: CIMMYT/Peter Lowe
EL BATÁN, MEXICO – 24 APRIL 2018–Farmers of irrigated wheat can increase profits and radically reduce greenhouse gas emissions by applying fertilizer in more precise dosages, according to a new study.
Published today in the journal Agriculture, Ecosystems and Environment, the study shows that farmers in the Yaqui Valley, a major breadbasket region in northwestern Mexico that covers over 1.5 times the area of the Mexico City, are applying significantly more nitrogen fertilizer than they need to maximize wheat yields.
Lower application of nitrogen fertilizer would cut the region’s yearly emissions of nitrous oxide, a potent greenhouse gas, by the equivalent of as much as 130,000 tons of carbon dioxide, equal to the emissions of 14 million gallons of gasoline, according to Neville Millar, a senior researcher at Michigan State University (MSU) and first author of the published paper.
“Our study is the first to isolate the effect of multiple nitrogen fertilizer rates on nitrous oxide emissions in wheat in the tropics or sub-tropics,” Millar said. “It shows that applying fertilizer to wheat at higher than optimal economic rates results in an exponential increase in nitrous oxide emissions.”
Yaqui Valley wheat farming conditions and practices are similar to those of huge wheat cropping expanses in China, India, and Pakistan, which together account for roughly half of worldwide nitrogen fertilizer use for wheat, according to study co-author Iván Ortíz-Monasterio, a wheat agronomist at the International Maize and Wheat Improvement Center (CIMMYT), whose Yaqui Valley experiment station was the site of the reported research.
“The recommendations are thus globally relevant and represent a potential triple win, in the form of reduced greenhouse gas emissions, higher income for farmers and continued high productivity for wheat cropping,” Ortíz-Monasterio said.
Measuring nitrous oxide after nitrogen fertilizer applications in spring durum wheat crops during two growing seasons, Millar and an international team of scientists found an exponential increase in emissions from plots fertilized at greater than economically-optimal rates—that is, when the extra nitrogen applied no longer boosts grain yield.
They also found that grain quality at the economically optimal N rates was not impacted and exceeded that required by local farmer associations for sale to the market. They examined five different nitrogen fertilizer dosages ranging from 0 to 280 kilograms per hectare.
“In our study, the highest dosage to get optimum wheat yields was 145 kilograms of nitrogen fertilizer per hectare in the 2014 crop,” said Millar. “Yaqui Valley farmers typically apply around 300 kilograms. The wheat crop takes up and uses only about a third of that nitrogen; the remainder may be lost to the atmosphere as gases, including nitrous oxide, and to groundwater as nitrate.”
Promoting profitable, climate-friendly fertilizer use
Farmers’ excessive use of fertilizer is driven largely by risk aversion and economic concerns, according to Ortíz-Monasterio. “Because crops in high-yielding years will require more nitrogen than in low-yielding years, farmers tend to be optimistic and fertilize for high-yielding years,” said Ortíz-Monasterio. “At the same time, since farmers don’t have data about available nitrogen in their fields, they tend to over-apply fertilizer because this is less costly than growing a crop that lacks the nitrogen to develop and yield near to full potential.”
Ortíz-Monasterio and his partners have been studying and promoting management practices to help farmers to use fertilizer more efficiently and take into account available soil nitrogen and weather. This technology, including Greenseeker, a handheld device that assesses plant nitrogen needs, was tested in a separate study for its ability to advise farmers on optimal rates of fertilizer use.
“Sensing devices similar to Greenseeker but mounted on drones are providing recommendations to Yaqui Valley farmers for wheat crops grown on more than 1,000 acres in 2017 and 2018,” Ortiz-Monasterio notes.
Part of a research partnership between CIMMYT and MSU’s W.K. Kellogg Biological Station (KBS) Long-Term Ecological Research program to reduce greenhouse gas impacts of intensive farming, a key aim of the present study was to generate new emission factors for Mexican grain crops that accurately reflect nitrous oxide emissions and emission reductions and can be used in global carbon markets, according to Millar.
“The emission calculations from our work can be incorporated by carbon market organizations into carbon market protocols, to help compensate farmers for reducing their fertilizer use,” he said.
“This study shows that low emissions nitrogen management is possible in tropical cereal crop systems and provides important guidance on the optimal levels for large cropping areas of the world,” said Lini Wollenberg, an expert in low-emissions agriculture for the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS), which helped fund the research. “With these improved emission factors, countries will be able to better plan and implement their commitments to reducing emissions.
To view the article
Millar, N., A. Urrea, K. Kahmark, I. Shcherbak, G. P. Robertson, and I. Ortiz-Monasterio. 2018. Nitrous oxide (N2O) flux responds exponentially to nitrogen fertilizer in irrigated wheat in the Yaqui Valley, Mexico. Agriculture, Ecosystems and Environment, https://doi.org/10.1016/j.agee.2018.04.003.
KBS LTER Michigan State University’s Kellogg Biological Station Long-term Ecological Research (KBS LTER) Program studies the ecology of intensive field crop ecosystems as part of a national network of LTER sites established by the National Science Foundation. More information at https://lter.kbs.msu.edu
MSU AgBioResearch MSU AgBioResearch engages in innovative, leading-edge research that combines scientific expertise with practical experience to help advance FOOD, ENERGY and the ENVIRONMENT. It encompasses the work of more than 300 scientists in seven MSU colleges — Agriculture and Natural Resources, Arts and Letters, Communication Arts and Sciences, Engineering, Natural Science, Social Science and Veterinary Medicine — and includes a network of 13 outlying research centers across Michigan.
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 www.cimmyt.org.
CCAFS The CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS), led by the International Center for Tropical Agriculture (CIAT), brings together some of the world’s best researchers in agricultural science, development research, climate science and earth system science to identify and address the most important interactions, synergies and tradeoffs between climate change, agriculture and food security. CCAFS is carried out with support from CGIAR Fund Donors and through bilateral funding agreements. www.ccafs.cgiar.org