Tag: land

Pilot farm in Yangambi, Democratic Republic of Congo. (Photo: Axel Fassio/CIFOR)

Getting to win-win: Can people and nature flourish on an increasingly cultivated planet?

Written by Steven M on June 15, 2022. Posted in Features.

Our planet is facing a massive biodiversity crisis. Deeply entwined with our concurrent climate crisis, this crisis may well constitute the sixth mass extinction in Earth’s history. Increasing agricultural production, whether by intensification of extensification, is a major driver of biodiversity loss. Beyond humanity’s moral obligation to not drive other species to extinction, biodiversity loss is also associated with the erosion of critical processes that maintain the Earth system in the only state that can support life as we know it. It is also associated with the emergence of novel, zoonotic pathogens like the SARS-CoV-2 virus that is responsible for the current COVID-19 global pandemic.

Conservation ecologists have proposed two solutions to this challenge: sparing or sharing land. The former implies practicing a highly intensive form of agriculture on a smaller land area, thereby “sparing” a greater proportion of land for biodiversity. The latter implies a multifunctional approach that boosts the density of wild flora and fauna on agricultural land. Both have their weaknesses though: sparing often leads to agrochemical pollution of adjacent ecosystems, while sharing implies using more land for any production target.

In an article in Biological Conservation, agricultural scientists at the International Maize and Wheat Improvement Center (CIMMYT), argue that, while both land sharing and sparing are part of the solution, the current debate is too focused on trade-offs and tends to use crop yield as the sole metric of agricultural performance. By overlooking potential synergies between agriculture and biodiversity and ignoring metrics that may matter more to farmers than yield —for example, income, labor productivity, or resilience — the authors argue that the two approaches have had limited impact on the adoption by farmers of practices with proven benefits on both biodiversity and agricultural production.

Beyond the zero-sum game

At the heart of the debate around land sparing versus land sharing is a common assumption: there is a zero-sum relationship between wild species density and agricultural productivity per unit of land. Hence, the answer to the challenge of balancing biodiversity conservation with feeding a growing human population appears to entail some unpalatable trade-offs, no matter which side of the debate you side with. As the debate has largely been driven by conservation ecologists, proposed solutions often approach conserving biodiversity in ways that offer limited benefits, and often losses, to farmers.

On the land sparing side, the vision is to carve up rural landscapes almost as a planner would zone urban space: some areas would be zoned for highly intensive forms of agricultural production, largely devoid of wild species, while others would be zoned as biodiversity-rich areas. As the authors point out, however, such a strictly segregated view of land use is challenged by the natural migratory patterns of species, their need for diverse types of ecosystems over the course of the seasons or their lifecycles, and the high risk of pollution associated with intensive agriculture, such as run-off and leaching of agrochemicals, and pesticide drift.

Proponents of the land sharing view argue for a multifunctional approach to agricultural production that introduces a greater density of wild species onto agricultural land, thus integrating production and conservation into the same land units. This, however, inevitably diminishes agricultural productivity, as measured by yield.

This view, the article argues, overlooks the synergies between agriculture and biodiversity. Not only can biodiversity support agriculture through ecosystem services, but farmlands also support many species. For example, the patchiness created in the landscape by swidden agriculture or by grazing livestock supports more biodiversity than closed-canopy ecosystems, benefiting open-habitat species in particular. And except for rare forms of “controlled environment agriculture” such as hydroponics, all agricultural systems depend on the ecosystem services rendered by a multitude of organisms, from soil fertility maintenance to pollination and pest control.

Tzeltal farmers in Chiapas, Mexico. (Photo: Peter Lowe for CIMMYT)

“Agriculture is about flexibility and pragmatism,” said Frédéric Baudron, a system agronomist at CIMMYT and the lead author of the study. “Farmers need to be presented with a wider basket of solutions than the dichotomy of high-yielding and polluting agriculture versus low-input and low-yielding agriculture offered by land sharing/sparing. Virtually all production systems require both external inputs and ecosystem services. In addition, agricultural scientists have developed a variety of solutions, such as precision agriculture, to minimize the risk of pollution when using external inputs, and push-pull technology to harness ecosystem services for tangible productivity gains.

Similarly, an exclusive focus on yield as a measure of agricultural performance obscures ways in which greater biodiversity on agricultural land can support farmers’ livelihoods and economic wellbeing. The authors show, for example, that simplified landscapes in southern Ethiopia tend to have higher crop productivity. But more diverse landscape in the same area, while hosting more biodiversity, produce more fuelwood, support a higher livestock productivity, provide a greater dietary diversity, and are more resilient to environmental stresses and external economic shocks, all of which being highly valued by local people.

Imagining landscapes where biodiversity and people win

The land sharing versus sparing debate deserves enormous credit for bringing attention to the role of agriculture in biodiversity loss and for pushing the scientific community and policymakers to address the problem and think about how to balance agriculture and conservation. As the authors of this paper show, as researchers from a more diverse range of scientific disciplines join the debate, there is tremendous potential to move the conversation from a vision that pits agriculture against biodiversity and towards solutions that highlight the potential synergies between these activities.

“It is our hope that this paper will stimulate other agricultural scientists to contribute to the debate on how to feed a growing population while safeguarding biodiversity. This is possibly one of the biggest challenges of our rapidly changing agri-food systems. But we have the technologies and the analytics to face this challenge,” Baudron said.

Cover photo: Pilot farm in Yangambi, Democratic Republic of Congo. (Photo: Axel Fassio/CIFOR)

Breaking Ground: Jordan Chamberlin avidly explores the changing landscapes of Africa

Written by Jérôme Bossuet on October 1, 2020. Posted in Features.

Sub-Saharan Africa is undergoing important transformations, including climate change, population growth, urbanization and migration flows, and growth in digital technologies. What can we say about the likely development trajectories that African rural economies are on, and the implications for poor farming households? These are central questions for Jordan Chamberlin, an economist at the International Maize and Wheat Improvement Center (CIMMYT) in Kenya.

Chamberlin’s desk is covered with screens teeming with numbers, complex mathematical equations, lines of code and aerial views of African landscapes. He combines traditional microeconomic analysis with geospatial modelling skills to study some of the ways in which rural transformations are occurring. In this era of big data, he examines the wealth of spatial and socioeconomic datasets to explore the relationships between drivers of change and smallholder welfare, sometimes revealing surprising insights on how rural communities in Africa are evolving.

“Are commercial farms good or bad for neighboring smallholder farmers? Which households can benefit from the rapidly evolving rural land markets in Africa? What drives migration between rural areas? These are some examples of the complex but increasingly important questions that inform how we understand the evolution of agri-food systems in developing countries,” Chamberlin explains. “Fortunately, we also increasingly have access to new data that helps us explore these issues.”

In addition to household survey datasets — the bread and butter of applied social scientists — today’s researchers are also able to draw on an ever-expanding set of geospatial data that helps us to better contextualize the decisions smallholder farmers make.

He cites current work, which seeks to understand input adoption behaviors through better measurement of the biophysical and marketing contexts in which small farms operate. “Evidence suggests that low use rates of inorganic fertilizer by smallholders is due in part to poor expected returns on such investments,” he explains, “which are the result of site-specific agronomic responses, rainfall uncertainty, variation in input-output price ratios, and other factors.”

We are increasingly able to control for such factors explicitly: one of Chamberlin’s recent papers shows the importance of soil organic carbon for location-specific economic returns to fertilizer investments in Tanzania. “After all, farmers do not care about yields for yields’ sake — they make agronomic investments on the basis of how those investments affect their economic welfare.”

Better data and models may help to explain why farmers sometimes do not adopt technologies that we generally think of as profitable. A related strand of his research seeks to better model the spatial distribution of rural market prices.

Jordan Chamberlin (left) talks to a farmer in Ethiopia’s Tigray region in 2019, while conducting research on youth outmigration from rural areas. (Photo: Jordan Chamberlin)

A spatial economist’s journey on Earth

Ever since his experience as a Peace Corps volunteer in Paraguay, where he worked as a beekeeping specialist, Chamberlin knew he wanted to spend his professional life working with smallholder farmers. He wanted to better understand how rural development takes place, and how policies and investments can help rural households to improve their welfare.

In pursuit of these interests, his academic journey took him from anthropology to quantitative geography, before leading him to agricultural economics. “While my fundamental interest in rural development has not changed, the analytical tools I have preferred have evolved over the years, and my training reflects that evolution,” he says.

Along with his research interests, he has always been passionate about working with institutions within the countries where his research has focused. While working with the International Food Policy Research Institute (IFPRI) in Ethiopia, he helped establish a policy-oriented GIS lab at the Ethiopian Development Research Institute (EDRI). Years later, as part of his work with Michigan State University, he served as director of capacity building at the Indaba Agricultural Policy Research Institute (IAPRI), a not-for-profit Zambian research organization. He continues to serve as an external advisor on PhD committees, and considers mentorship a key part of his professional commitments.

He joined CIMMYT at the Ethiopia office in 2015 as spatial economist, part of the foresight and ex ante group of the Socioeconomics program.

As part of his research portfolio, he explores the role of new technologies, data sources and extension methods in the scaling of production technologies. Under the Taking Maize Agronomy to Scale in Africa (TAMASA) project, one area he has been working on is how we may better design location-specific agronomic advisory tools. Working with the Nutrient Expert tool, developed by the African Plant Nutrition Institute (APNI), he and his research team have conducted randomized control trials in Ethiopia and Nigeria to evaluate the impacts of such decision-support tools on farmer investments and productivity outcomes. They found that such tools appear to contribute to productivity gains, although tool design matters — for example, Nigerian farmers were more likely to take up site-specific agronomic recommendations when such information was accompanied by information about uncertainty of financial returns.

Jordan Chamberlin (center) talks to colleagues during a staff gathering in Nairobi. (Photo. Joshua Masinde/CIMMYT)

Creative rethinking

While Chamberlin’s research portfolio is diverse, one commonality is the drive to use new data and tools to better guide how development resources are allocated.

“Given the scarcity of resources available to governments and their partners, it is important to have sound empirical foundations for the allocation of these resources. Within CIMMYT, I see my role as part of a multidisciplinary team whose goal is to generate such empirical guidance,” he says.

This research also contributes to better design of agricultural development policies.

“Even though many of the research topics that my team addresses are not traditional areas of emphasis within CIMMYT’s socioeconomic work, I hope that we are demonstrating the value of broad thinking about development questions, which are of fundamental importance to one of our core constituencies: the small farmers of the region’s maize and wheat-based farming systems.”

Forests in the land of the Ese'eja Native Community of Infierno, in Peru's Madre de Dios department. (Photo: Yoly Gutierrez/CIFOR)

Safeguarding biodiversity is essential to prevent the next COVID-19

Written by Alison Doody on April 8, 2020. Posted in Features. 11 Comments on Safeguarding biodiversity is essential to prevent the next COVID-19

Disclaimer: The views and opinions expressed in this article are those of the authors and do not necessarily reflect the official views or position of the International Maize and Wheat Improvement Center (CIMMYT).

While the world’s attention is focused on controlling COVID-19, evidence points at the biodiversity crisis as a leading factor in its emergence. At first glance, the two issues might seem unrelated, but disease outbreaks and degraded ecosystems are deeply connected. Frédéric Baudron, systems agronomist at the International Maize and Wheat Improvement Center (CIMMYT) and Florian Liégeois, virologist at the Institut de Recherche pour le Développement (IRD) share their insights on the current COVID-19 crisis and the link between biodiversity loss and emerging infectious diseases.

What trends are we seeing with infectious diseases like COVID-19?

We see that outbreaks of infectious diseases are becoming more frequent, even when we account for the so-called “reporting bias”: surveillance of such events becoming better with time and surveillance being better funded in the North than in the South.

60% of infectious diseases are zoonotic, meaning that they are spread from animals to humans and 72% of these zoonoses originate from wildlife. COVID-19 is just the last in a long list of zoonoses originating from wildlife. Other recent outbreaks include SARS, Ebola, avian influenza and swine influenza. As human activities continue to disturb ecosystems worldwide, we are likely to see more pathogens crossing from wildlife to humans in the future. This should serve as a call to better manage our relationship with nature in general, and wildlife in particular.

Researchers in Zimbabwe enter the cave dwelling of insectivorous bats (Hipposideros caffer) to conduct fecal sampling for viral research. (Photo: Florian Liégeois/IRD)

Why are we seeing more cases of diseases crossing from animals to humans? Where are they coming from?

Evidence points to bushmeat trade and consumption as the likely driver for the emergence of COVID-19. The emergence of SARS and Ebola was also driven by bushmeat consumption and trade. However, when looking at past outbreaks of zoonoses caused by a pathogen with a wildlife origin, land use changes, generally due to changes in agricultural practices, has been the leading driver.

Pathogens tends to emerge in well known “disease hotspots,” which tend to be areas where high wildlife biodiversity overlaps with high population density. These hotspots also tend to be at lower latitude. Interestingly, many of these are located in regions where CIMMYT’s activities are concentrated: Central America, East Africa and South Asia. This, in addition to the fact that agricultural changes are a major driver of the emergence of zoonoses, means that CIMMYT researchers may have a role to play in preventing the next global pandemic.

Smallholders clear forests for agriculture, but they also have an impact on forests through livestock grazing and fuelwood harvesting, as on this picture in Munesa forest, Ethiopia. (Photo: Frederic Baudron/CIMMYT)

How exactly does biodiversity loss and land use change cause an increase in zoonotic diseases?

There are at least three mechanisms at play. First, increased contact between wildlife and humans and their livestock because of encroachment in ecosystems. Second, selection of wildlife species most able to infect humans and/or their livestock — often rodents and bats — because they thrive in human-dominated landscapes. Third, more pathogens being carried by these surviving wildlife species in simplified ecosystems. Pathogens tend to be “diluted” in complex, undisturbed, ecosystems.

The fast increase in the population of humans and their livestock means that they are interacting more and more frequently with wildlife species and the pathogens they carry. Today, 7.8 billion humans exploit almost each and every ecosystem of the planet. Livestock have followed humans in most of these ecosystems and are now far more numerous than wild vertebrates: there are 4.7 billion cattle, pigs, sheep and goats and 23.7 billion chickens on Earth! We live on an increasingly “cultivated planet,” with new species assemblages and new opportunities for pathogens to move from one species to another.

Wildlife trade and bushmeat consumption have received a lot of attention as primary causes of the spread of these viruses. Why has there been so little discussion on the connection with biodiversity loss?

The problem of biodiversity loss as a driver of the emergence of zoonoses is a complex one: it doesn’t have a simple solution, such as banning wet markets in China. It’s difficult to communicate this issue effectively to the public. It’s easy to find support for ending bushmeat trade and consumption because it’s easy for the public to understand how these can lead to the emergence of zoonoses, and sources of bushmeat include emblematic species with public appeal, like apes and pangolins. Bushmeat trafficking and consumption also gives the public an easy way to shift the blame: this is a local, rather than global, issue and for most of us, a distant one.

There is an inconvenient truth in the biodiversity crisis: we all drive it through our consumption patterns. Think of your annual consumption of coffee, tea, chocolate, sugar, textiles, fish, etc. But the biodiversity crisis is often not perceived as a global issue, nor as a pressing one. Media coverage for the biodiversity crisis is eight times lower than for the climate crisis.

The Unamat forest in Puerto Maldonado, Madre de Dios department, Peru. (Photo: Marco Simola/CIFOR)

Agriculture is a major cause of land use change and biodiversity loss. What can farmers do to preserve biodiversity, without losing out on crop yields?

Farming practices that reduce the impact of agriculture on biodiversity are well known and form the foundation of sustainable intensification, for which CIMMYT has an entire program. A better question might be what we can do collectively to support them in doing so. Supportive policies, like replacing subsidies by incentives that promote sustainable intensification, and supportive markets, for example using certification and labeling, are part of the solution.

But these measures are likely to be insufficient alone, as a large share of the global food doesn’t enter the market, but is rather consumed by the small-scale family farmers who produce it.

Reducing the negative impact of food production on biodiversity is likely to require a global, concerted effort similar to the Paris Agreements for climate. As the COVID-19 pandemic is shocking the world, strong measures are likely to be taken globally to avoid the next pandemic. There is a risk that some of these measures will go too far and end up threatening rural livelihoods, especially the most vulnerable ones. For example, recommending “land sparing” — segregating human activities from nature by maximizing yield on areas as small as possible — is tempting to reduce the possibility of pathogen spillover from wildlife species to humans and livestock. But food production depends on ecosystem services supported by biodiversity, like soil fertility maintenance, pest control and pollination. These services are particularly important for small-scale family farmers who tend to use few external inputs.

How can we prevent pandemics like COVID-19 from happening again in the future?

There is little doubt that new pathogens will emerge. First and foremost, we need to be able to control emerging infectious diseases as early as possible. This requires increased investment in disease surveillance and in the health systems of the countries where the next infectious disease is most likely to emerge. In parallel, we also need to reduce the frequency of these outbreaks by conserving and restoring biodiversity globally, most crucially in disease hotspots.

Farming tends to be a major driver of biodiversity loss in these areas but is also a main source of livelihoods. The burden of reducing the impact of agriculture on biodiversity in disease hotspots cannot be left to local farmers, who tend to be poor small-scale farmers: it will have to be shared with the rest of us.

Cover photo: Forests in the land of the Ese’eja Native Community of Infierno, in Peru’s Madre de Dios department. (Photo: Yoly Gutierrez/CIFOR)

A farmers group stands for a photograph at a demonstration plot of drought-tolerant (DT) maize in the village of Lobu Koromo, in Ethiopia’s Hawassa Zuria district. (Photo: P. Lowe/CIMMYT)

New publications: Understanding changes in farming systems to propose adapted solutions

Written by Natasha Nagarajan on November 28, 2019. Posted in Publications.

Farming systems are moving targets. Agricultural Research and Development (R&D) must understand where they come from and where they are going to offer solutions that are adapted. This is one of the main objectives of the Trajectories and Trade-offs for Intensification of Cereal-based systems (ATTIC), project funded by the CGIAR Research Program on Maize (MAIZE) and implemented by the International Maize and Wheat Improvement Center (CIMMYT) and the Farming System Ecology group at Wageningen University & Research.

A recent study led by Yodit Kebede — who obtained her PhD last year under the ATTIC project — examined the drivers of change affecting smallholder farming in southern Ethiopia, farmer’s responses to these changes, and consequences for agricultural landscapes.

As in many parts of the developing world, small farms in southern Ethiopia have become smaller. Population increase and urban expansion have been major drivers of this change. Population has been increasing over 3% annually in Ethiopia, the second most populated country in Africa. Grazing areas and forests were converted to cropland, putting stress on the availability of livestock feed and fuelwood.

Farmers responded to these changes through three broad trajectories: diversification — mixed cropping and intercropping, particularly for the smallest farms —, specialization — often in high-value but non-food crops — and consolidation — maintenance or increase of farm area. Each of these trajectories has its own specific R&D needs, although farms following a consolidation trajectory are often favored by R&D programs. The same three trajectories can be identified in many rural areas where rural transformation has not taken place yet, in Africa and elsewhere in the developing world.

The loss of grassland and forest produced a landscape more susceptible to erosion and loss of soil fertility. However, all outcomes from these landscape changes may not be negative. Another study conducted by the same authors in the same study area demonstrated that an increasingly fragmented agricultural landscape may lead to increased pest control by natural enemies.

While aiming to mitigate against negative outcomes from landscape changes — for example, land degradation — policies should be careful not to inadvertently reduce some of the positive outcomes of these changes, such as increased pest control. As concluded by the study, “a better understanding of interlinkages and tradeoffs among ecosystem services and the spatial scales at which the services are generated, used, and interact is needed in order to successfully inform future land use policies”.

Read the full study:
Drivers, farmers’ responses and landscape consequences of smallholder farming systems changes in southern Ethiopia

See more recent publications by CIMMYT researchers:

Estimation of hydrochemical unsaturated soil parameters using a multivariational objective analysis. 2019. Lemoubou, E.L., Kamdem, H.T.T., Bogning, J.R., Tonnang, H. In: Transport in Porous Media v. 127, no. 3, p. 605-630.
Analyses of African common bean (Phaseolus vulgaris L.) germplasm using a SNP fingerprinting platform : diversity, quality control and molecular breeding. 2019. Raatz, B., Mukankusi, C., Lobaton, J.D., Male, A., Chisale, V., Amsalu, B., Fourie, D., Mukamuhirwa, F., Muimui, K., Mutari, B., Nchimbi-Msolla, S., Nkalubo, S., Tumsa, K., Chirwa, R., Maredia, M.K., He, Chunlin In: Genetic Resources and Crop Evolution v.66, no. 3, p. 707-722.
Deep blade loosening increases root growth, organic carbon, aeration, drainage, lateral infiltration and productivity. 2019. Hamilton, G.J., Bakker, D., Akbar, G., Hassan, I., Hussain, Z., McHugh, A., Raine, S.R. In: Geoderma v. 345, p. 72-92.
Maize crop nutrient input requirements for food security in sub-Saharan Africa. 2019. Berge, H.F.M. ten., Hijbeek, R., Loon, M.P. van., Rurinda, J., Fantaye, K. T., Shamie Zingore, Craufurd, P., Heerwaarden, J., Brentrup, F., Schröder, J.J., Boogaard, H., Groot, H.L.E. de., Ittersum, M.K. van. In: Global Food Security v. 23 p. 9-21.
Primary hexaploid synthetics : novel sources of wheat disease resistance. 2019. Shamanin, V., Shepelev, S.S., Pozherukova, V.E., Gultyaeva, E.I., Kolomiets, T., Pakholkova, E.V., Morgounov, A.I. In: Crop Protection v. 121, p. 7-10.
Understanding the factors influencing fall armyworm (Spodoptera frugiperda J.E. Smith) damage in African smallholder maize fields and quantifying its impact on yield. A case study in Eastern Zimbabwe. 2019. Baudron, F., Zaman-Allah, M., Chaipa, I., Chari, N., Chinwada, P. In: Crop Protection v. 120 p. 141-150.
Predicting dark respiration rates of wheat leaves from hyperspectral reflectance. 2019. Coast, O., Shahen Shah, Ivakov, A., Oorbessy Gaju, Wilson, P.B., Posch, B.C., Bryant, C.J., Negrini, A.C.A., Evans, J.R., Condon, A.G., Silva‐Pérez, V., Reynolds, M.P. Pogson, B.J., Millar A.H., Furbank, R.T., Atkin, O.K. In: Plant, Cell and Environment v. 42, no. 7, p. 2133-2150.
Morphological and physiological responses of Guazuma ulmifolia Lam. to different pruning dates. 2019. Ortega-Vargas, E., Burgueño, J., Avila-Resendiz, C., Campbell, W.B., Jarillo-Rodriguez, J., Lopez-Ortiz, S. In: Agroforestry Systems v. 93 no. 2 p. 461-470.
Stripe rust resistance in wild wheat Aegilops tauschii Coss.: genetic structure and inheritance in synthetic allohexaploid Triticum wheat lines. 2019. Kishii, M., Huerta-Espino, J., Hisashi Tsujimoto, Yoshihiro Matsuoka. In: Genetic Resources and Crop Evolution v. 66, no. 4, p. 909-920.
Comparative assessment of food-fodder traits in a wide range of wheat germplasm for diverse biophysical target domains in South Asia. 2019. Blummel, M., Updahyay, S.R., Gautam, N.R., Barma, N.C.D., Abdul Hakim, M., Hussain, M., Muhammad Yaqub Mujahid, Chatrath, R., Sohu, V.S., Gurvinder Singh Mavi, Vinod Kumar Mishra, Kalappanavar, I.K., Vaishali Rudra Naik, Suma S. Biradar., Prasad, S.V.S., Singh, R.P., Joshi, A.K. In: Field Crops Research v. 236, p. 68-74.
Comment on ‘De Roo et. al. (2019). On-farm trials for development impact? The organization of research and the scaling of agricultural technologies. 2019. Wall, P.C., Thierfelder, C., Nyagumbo, I., Rusinamhodzi, L., Mupangwa, W. In: Experimental Agriculture v. 55 no. 2 p. 185-194.
High-throughput phenotyping enabled genetic dissection of crop lodging in wheat. 2019. Singh, D., Xu Wang, Kumar, U., Liangliang Gao, Muhammad Noor, Imtiaz, M., Singh, R.P., Poland, J.A. In: Frontiers in Plant Science v. 10 art. 394.
Differential response from nitrogen sources with and without residue management under conservation agriculture on crop yields, water-use and economics in maize-based rotations. 2019. Jat, S.L., Parihar, C.M., Singh, A.K., Hari S. Nayak, Meena, B.R., Kumar, B., Parihar M.D., Jat, M.L. In: Field Crops Research v. 236, p. 96-110.
Drip irrigation and nitrogen management for improving crop yields, nitrogen use efficiency and water productivity of maize-wheat system on permanent beds in north-west India. 2019. Sandhu, O.S., Gupta, R.K., Thind, H.S., Jat, M.L., Sidhu, H.S., Singh, Y. In: Agricultural Water Management v. 219 p. 19-26.
Impact of tillage and crop establishment methods on crop yields, profitability and soil physical properties in rice–wheat system of Indo‐gangetic plains of India. Kumar, V., Gathala, M.K., Saharawat, Y.S., Parihar, C.M., Rajeev Kumar, Kumar, R., Jat, M.L., Jat, A.S., Mahala, D.M., Kumar, L., Hari S. Nayak, Parihar M.D., Vikas Rai, Jewlia, H.R., Bhola R. Kuri In: Soil Use and Management v. 35, no. 2, p. 303-313.
Increasing profitability, yields and yield stability through sustainable crop establishment practices in the rice-wheat systems of Nepal. 2019. Devkota, M., Devkota, K.P., Acharya, S., McDonald, A. In: Agricultural Systems v. 173, p. 414-423.
Identification of donors for low-nitrogen stress with maize lethal necrosis (MLN) tolerance for maize breeding in sub-Saharan Africa. 2019. Das, B., Atlin, G.N., Olsen, M., Burgueño, J., Amsal Tesfaye Tarekegne, Babu, R., Ndou, E., Mashingaidze, K., Lieketso Moremoholo |Ligeyo, D., Matemba-Mutasa, R., Zaman-Allah, M., San Vicente, F.M., Prasanna, B.M., Cairns, J.E. In: Euphytica v. 215, no. 4, art. 80.
On-farm trials as ‘infection points’? A response to Wall et al. 2019. Andersson, J.A., Krupnik, T.J., De Roo, N. In: Experimental Agriculture v. 55, no. 2 p. 195-199.
Doing development-oriented agronomy: Rethinking methods, concepts and direction. 2019. Andersson, J.A., Giller, K.Ehttps://repository.cimmyt.org/handle/10883/20154. In: Experimental Agriculture v. 55, no. 2, p. 157-162.
Scale-appropriate mechanization impacts on productivity among smallholders : Evidence from rice systems in the mid-hills of Nepal. 2019. Paudel, G.P., Dilli Bahadur KC, Rahut, D.B., Justice, S., McDonald, A. In: Land Use Policy v. 85, p. 104-113.

View from the experimental station in Ciudad Obregón, Sonora, northern Mexico. (Photo: M. Ellis/CIMMYT)

Warmer night temperatures reduce wheat yields in Mexico, scientists say

Written by Rodrigo Ordóñez on August 8, 2019. Posted in Features.

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 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.

Wheat fields at CIMMYT's experimental station near Ciudad Obregón, Sonora, Mexico. (Photo: M. Ellis/CIMMYT) — Wheat fields at CIMMYT’s experimental station near Ciudad Obregón, Sonora, Mexico. (Photo: M. Ellis/CIMMYT)

Climate challenge

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.

CIMMYT wheat physiologist Gemma Molero presents at the International Wheat Congress. (Photo: Marcia MacNeil/CIMMYT)

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, for example.

More than 800 global experts gathered at the first International Wheat Congress in Saskatoon, Canada, to strategize on ways to meet projected nutritional needs of 60% more people by 2050. (Photo: Matthew Hayes/Cornell University)

Collaborative effort

Matthew Reynolds, a distinguished scientist at CIMMYT, is joint founder of the Heat and Drought Wheat Improvement Consortium (HeDWIC), a coalition of hundreds of scientists and stakeholders from over 30 countries.

“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 translational research and developing a bioinformatics cyber-infrastructure, he said, adding that attracting multi-year funding for international collaborations remains a challenge.

Nitrogen traits

Another 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.

CIMMYT's director general Martin Kropff speaks at a session of the International Wheat Congress. (Photo: Matthew Hayes/Cornell University) — CIMMYT’s director general Martin Kropff speaks at a session of the International Wheat Congress. (Photo: Matthew Hayes/Cornell University)

Scientists with the BNI research consortium, which includes Japan’s International Research Center for Agricultural Sciences (JIRCAS), propose transferring the BNI trait from those plants to critical food and feed crops, such as wheat, sorghum and Brachiaria range grasses.

“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.

“BNI 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.

Hans-Joachim Braun,
Director of CIMMYT’s Global Wheat Program and the CGIAR Research Program on Wheat, speaks at the International Wheat Congress. (Photo: Marcia MacNeil/CIMMYT)

Although ruminant livestock are responsible for generating roughly half of all agricultural production emissions, BNI offers potential for reducing overall emissions, said Tim Searchinger, senior fellow at the World Resources Institute and technical director of a new report titled “Creating a Sustainable Food Future: A Menu of Solutions to Feed Nearly 10 Billion People by 2050.”

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.

A farm worker carrying her baby on her back weeds maize in Tanzania. (Photo: Peter Lowe/CIMMYT)

Are high land rental costs pricing African youth out of agriculture?

Written by Matthew O'Leary on June 21, 2019. Posted in News.

A new study shows that youth can face higher land rental prices than older farmers in Tanzania and other parts of sub-Saharan Africa.

“The rising importance of land rental markets reflects increasing rural population densities in many parts of the continent,” said Jordan Chamberlin, an agricultural economist with the International Maize and Wheat Improvement Center (CIMMYT) and study co-author.

“Evidence that the effective costs of rental market participation are relatively higher for younger farmers suggests that the markets are not yet mature,” Chamberlin explained. “This appears to stem partly from weak contract enforcement norms that make land rental arrangements more sensitive to trust and reputation. That puts younger farmers, who have not yet built up such social capital stocks, at a disadvantage.”

As many as three-quarters of Tanzanian youth are employed in agriculture, and with rural populations in Africa expected to rise over the next several decades, the region will experience an increasing scarcity of land relative to labor.

Young people today are already inheriting less land than previous generations and waiting longer to obtain the land they do inherit, according to the authors, who observe as one result a rising dependence on labor markets.

“Wage income’s importance will continue to rise in rural areas of sub-Saharan Africa, but policymakers should also foster equitable access to land for young agricultural entrepreneurs,” said Chamberlin.

The authors recommend measures such as tenant-landlord “matchmaking” programs, arrangements that encourage land sales by older farmers to younger farmers, and clarifying and simplifying regulations and procedures for title conversions and land purchases.

“Local governments may also share information about land rental rates for different areas, to provide a reference for rental negotiations,” added Chamberlain.

Read the study:
“Transaction Costs, Land Rental Markets, and Their Impact on Youth Access to Agriculture in Tanzania”