Kai Sonder

Adapting maize production to climate change in sub-Saharan Africa

Given the accumulating evidence of climate change in sub-Saharan Africa, there is an urgent need to develop more climate resilient maize systems. Adaptation strategies to climate change in maize systems in sub-Saharan Africa are likely to include improved germplasm with tolerance to drought and heat stress and improved management practices. Adapting maize systems to future climates requires the ability to accurately predict future climate scenarios in order to determine agricultural responses to climate change and set priorities for adaptation strategies. Here we review the projected climate change scenarios for Africa’s maize growing regions using the outputs of 19 global climate models. By 2050, air temperatures are expected to increase throughout maize mega- environments within sub-Saharan Africa by an average of 2.1°C. Rainfall changes during the maize growing season varied with location. Given the time lag between the development of improved cultivars until the seed is in the hands of farmers and adoption of new management practices, there is an urgent need to prioritise research strategies on climate change resilient germplasm development to offset the predicted yield declines.

Maize Production in a Changing Climate: Impacts, Adaptation, and Mitigation Strategies

Abstract Plant breeding and improved management options have made remarkable progress in increasing crop yields during the past century. However, climate change projections suggest that large yield losses will be occurring in many regions, particularly within sub-Saharan Africa. The development of climate-ready germplasm to offset these losses is of the upmost importance. Given the time lag between the development of improved germplasm and adoption in farmers’ fields, the development of improved breeding pipelines needs to be a high priority. Recent advances in molecular breeding provide powerful tools to accelerate breeding gains and dissect stress adaptation. This review focuses on achievements in stress tolerance breeding and physiology and presents future tools for quick and efficient germplasm development. Sustainable agronomic and resource management practices can effectively contribute to climate change mitigation. Management options to increase maize system resilience to climate-related stresses and mitigate the effects of future climate change are also discussed.

Phenotyping for Abiotic Stress Tolerance in Maize

The ability to quickly develop germplasm having tolerance to several complex polygenic inherited abiotic and biotic stresses combined is critical to the resilience of cropping systems in the face of climate change. Molecular breeding offers the tools to accelerate cereal breeding; however, suitable phenotyping protocols are essential to ensure that the much-anticipated benefits of molecular breeding can be realized. To facilitate the full potential of molecular tools, greater emphasis needs to be given to reducing the within-experimental site variability, application of stress and characterization of the environment and appropriate phenotyping tools. Yield is a function of many processes throughout the plant cycle, and thus integrative traits that encompass crop performance over time or organization level (i.e. canopy level) will provide a better alternative to instantaneous measurements which provide only a snapshot of a given plant process. Many new phenotyping tools based on remote sensing are now available including non-destructive measurements of growth-related parameters based on spectral reflectance and infrared thermometry to estimate plant water status. Here we describe key field phenotyping protocols for maize with emphasis on tolerance to drought and low nitrogen.

Maize Production in a Changing Climate

Abstract Plant breeding and improved management options have made remarkable progress in increasing crop yields during the past century. However, climate change projections suggest that large yield losses will be occurring in many regions, particularly within sub-Saharan Africa. The development of climate-ready germplasm to offset these losses is of the upmost importance. Given the time lag between the development of improved germplasm and adoption in farmers’ fields, the development of improved breeding pipelines needs to be a high priority. Recent advances in molecular breeding provide powerful tools to accelerate breeding gains and dissect stress adaptation. This review focuses on achievements in stress tolerance breeding and physiology and presents future tools for quick and efficient germplasm development. Sustainable agronomic and resource management practices can effectively contribute to climate change mitigation. Management options to increase maize system resilience to climate-related stresses and mitigate the effects of future climate change are also discussed.

Maize systems under climate change in sub-Saharan Africa

Purpose – The purpose of this study is to examine the biophysical and socioeconomic impacts of climate change on maize production and food security in sub-Saharan Africa (SSA) using adapted improved maize varieties and well-calibrated and validated bioeconomic models. Design/methodology/approach – Using the past climate (1950-2000) as a baseline, the study estimated the biophysical impacts of climate change in 2050 (2040-2069) and 2080 (2070-2099) under the A1B emission scenario and three nitrogen levels, and the socioeconomic impacts in 2050. Findings – Climate change will affect maize yields across SSA in 2050 and 2080, and the extent of the impact at a given period will vary considerably between input levels, regions and maize mega environments (MMEs). Greater relative yield reductions may occur under medium and high-input intensification than under low intensification, in Western and Southern Africa than in Eastern and Central Africa and in lowland and dry mid-altitude than in highland and wet mid-alt...

Climate change and food security in the developing world: Potential of maize and wheat research to expand options for adaptation and mitigation

Maize and wheat are two of the most important food crops worldwide. Together with rice, they provide 30% of the food calories to 4.5 billion people in almost 100 developing countries. Predictions suggest that climate change will reduce maize production globally by 3 to 10% by 2050 and wheat production in developing countries by 29 to 34%. This will coincide with a substantial increase in demand for maize and wheat due to rising populations. Maize and wheat research has a crucial role to play in enhancing adaptation to and mitigation of climate change while also enhancing food security. Crop varieties with increased tolerance to heat and drought stress and resistance to pests and diseases are critical for managing current climatic variability and for adaptation to progressive climate change. Furthermore, sustainable agronomic and resource management practices, such as conservation agriculture and improved nitrogen management can contribute to climate change mitigation. There is also a need for better policies and investments in infrastructure to facilitate technology adoption and adaptation. These include investments in irrigation, roads, storage facilities and improved access to markets. There is also a need for policy innovations for stabilizing prices, diversifying incomes, increasing farmer access to improved seeds and finance, and providing safety nets to enhance farmers’ livelihood security. This review paper details the potential impacts of climate change on food security, and the key role of improved technologies and policy and institutional innovations for climate change adaptation and mitigation. The focus is on maize and wheat in sub-Saharan Africa and South Asia.

Climate change at winter wheat breeding sites in central Asia, eastern Europe, and USA, and implications for breeding

Key weather parameters (monthly minimum and maximum temperature, precipitation) were extracted for 35 winter wheat breeding sites in central Asia, eastern Europe and Great Plains of USA from 1961 to 2009. Autumn and winter warming happened gradually, over a long period of time, but mostly before 1991. Climate changes after 1991 were mainly expressed through higher temperatures in spring, May, and June. Clear regional differences were observed for air temperature variation. Breeding sites in the USA seemed to be least subjected to climate change. There were no significant linear trends in yearly, seasonal, or monthly precipitation. Changing climates expressed through rising temperatures during critical stages of winter wheat development have already negatively affected yield gains in several countries, especially in eastern Europe. There are some positive changes associated with warmer winters, which may not require additional investment in traits associated with winter survival. Rising temperatures in spring are of particular concern since their effect on yield is negative in some regions. They certainly accelerate wheat development and shift heading to earlier dates. The interaction of higher temperatures in spring with the rate of crop development and yield is a fundamental issue which requires research. Rising temperatures in June are detrimental for grain development and filling and heat tolerance warrants high priority in breeding programs.

Improving global integration of crop research

Field laboratories in realistic crop environments are needed In recent decades, the scientific, development, and farm communities have contributed to substantial gains in crop productivity, including in many less developed countries (LDCs) (1), yet current yield trends and agri-food systems are inadequate to match projected demand (2). Addressing transnational crop challenges will require refinement of research infrastructure and better leverage of global expertise and technologies. Drawing on lessons learned from international collaboration in wheat, we outline how such a model could evolve into a Global Crop Improvement Network (GCIN) encompassing most staple food crops, providing access to well-controlled “field laboratories,” while harmonizing research practices and sharing data. Combined with socioeconomic and cropping systems research, a GCIN could revolutionize the ability to understand and model crop responses to environments globally and accelerate adoption of vital technologies.

A Multi-Criteria GIS Site Selection for Sustainable Cocoa Development in West Africa: A Case Study of Nigeria

Cocoa occupies 6 million hectares in humid coastal West Africa where 70% of the world supply is grown, 90% of which is produced on 2 million family farms of 2 hectares or less. Here, at least 16 million people depend on cocoa but earn only

Strategic crossing of biomass and harvest index—source and sink—achieves genetic gains in wheat

100/person/year from the crop. There is need to optimize the farming system, minimize the environmental impact of technologies, and improve socio-economic dynamics. This study identifies areas with potential for intensified cocoa farming and where maximum impact to household income could be achieved without deforestation. The selection involves defining suitability criteria, preparing an inventory of available data, determining suitability based on identified criteria, and combining suitability into hierarchical preferences based on weights proposed by local experts. GIS and Multi-Criteria land Evaluation technique using biophysical, socioeconomic, and demographic variables were employed in selection. Nineteen administrative units were selected in Nigeria where the intervention project could be implemented.