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Conservation agriculture is widely promoted across sub-Saharan Africa as a sustainable farming practice that enhances adaptive capacity to climate change. The interactions between climate stress, management, and soil are critical to understanding the adaptive capacity of conservation agriculture. Yet conservation agriculture syntheses to date have largely neglected climate, especially the effects of extreme heat.For the sub-tropics and tropics, we use meta-regression, in combination with global soil and climate datasets, to test four hypotheses: (1) that relative yield performance of conservation agriculture improves with increasing drought and temperature stress; (2) that the effects of moisture and temperature stress exposure interact; (3) that the effects of moisture and temperature stress are modified by soil texture; and (4) that crop diversification, fertilizer application rate, or the time since no-till implementation will enhance conservation agriculture performance under climate stress.Our results support the hypothesis that the relative maize yield performance of conservation agriculture improves with increasing drought severity or exposure to high temperatures. Further, there is an interaction of moisture and heat stress on conservation agriculture performance and their combined effect is both non-additive and modified by soil clay content, supporting our second and third hypotheses. Finally, we found only limited support for our fourth hypothesis as (1) increasing nitrogen application rates did not improve the relative performance of conservation agriculture under high heat stress; (2) crop diversification did not notably improve conservation agriculture performance, but did increase its stability with heat stress; and (3) a statistically robust effect of the time since no-till implementation was not evident.Our meta-regression supports the narrative that conservation agriculture enhances the adaptive capacity of maize production in sub-Saharan Africa under drought and/or heat stress. However, in very wet seasons and on clay-rich soils, conservation agriculture yields less compared to conventional practices.

Climate‐smart agriculture (CSA) serves as a credible mechanism to simultaneously address food security, climate change, and agricultural productivity. Despite the widespread adoption of CSA approaches across West Africa, many countries have still not been able to resolve the problems of food insecurity and rural poverty. This systematic review evaluates published evidence on the types of CSA practices, the determinants and benefits of adoption, and the barriers confronting the adoption of CSA practices across West Africa, following the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses statement checklist. Articles published in English from January 2010 to March 2023 investigating the benefits of and barriers to the adoption of CSA practices in West Africa were retrieved from ScienceDirect, Web of Science, and Scopus databases. The methodological quality of studies was assessed using Joanna Briggs Institute critical appraisal tools for use in systematic reviews. The themes emerging from the articles were extracted, and a summary was provided to illustrate each theme. After applying the eligibility criteria, 12 articles were included in the final review. The studies reviewed revealed that farmers used more knowledge‐, water‐, carbon‐, and nitrogen‐smart practices, compared to weather‐ and energy‐smart practices. Across the reviewed papers, factors such as the education level of farmers, age, gender, household size, membership of a social group, agricultural extension services, and access to credit/financial resources influenced CSA adoption. The reviewed studies identified that farmers who used CSA practices reported benefits such as improved soil fertility, higher yield, improved household income, climate resilience (such as overcoming the effects of drought and extreme temperatures), and food security. Some farmers adopted CSA practices to reduce the effect of droughts and high temperatures on their crops, and thus increase their resilience to climate variability and change. However, farmers' adoption is confronted with challenges related to the technicality of some CSA practices, high cost of labor for CSA implementation, lack of credit and government support, limited access to weather and climate information, limited information about CSA options, high illiteracy level of smallholder farmers, and incompatibility of some practices with farmers' crop of interest. Our findings show that most CSA practices in the studies we reviewed are not well targeted to meet farmers' crop of interest, and that governments should provide more practical training to enhance farmers' understanding of CSA practices, especially those related to weather‐ and energy‐smart initiatives. There should also be more robust financial and institutional support to improve the adoption and usage of CSA practices at all levels. Additionally, socio‐cultural factors such as values, customs, and beliefs should be properly integrated into CSA plans as they influence the adoption of CSA practices. [ABSTRACT FROM AUTHOR]

The dominance of a few staple crops (maize, rice, and wheat) in most agricultural systems hampers the application of interventions to improve food security and nutrition. Research and development attention has focused on improving the production and utilization of these crops, leaving other crops under‐researched and underutilized. Subsequently, there have been high malnutrition rates due to poor diet diversity, yet there are "opportunity crops" that remain under researched. The opportunity crops can unlock solutions to food insecurity, malnutrition, a lack of biodiversity, and indeed poor climate adaptation. The study explored diversification in agricultural systems to analyze whether reorientation of research investment to include under‐researched crops can increase nutrient gain and enhance dietary diversity. Research outputs benchmarked as the number of publications from three leading African universities, Nairobi, Pretoria, and Ghana, were related to crop diversity and nutrition of crops in five clusters: cereals, vegetables, legumes, roots and tubers, and nuts. The findings show that maize was the predominantly researched crop across the three institutions. Low research outputs were observed for pearl millet, finger millet, and yam across the three institutions: amaranth and nightshade (Pretoria), sweet potatoes (Pretoria and Ghana), Marama bean (Nairobi), and soya bean (Nairobi and Ghana). There was nutrient gain across all five clusters, particularly from under‐researched indigenous crops such as finger millet, amaranth, nightshade, yam, sweet potatoes, Marama bean, and soybean. Nutrient gain was contributed more by cereals and root and tuber crops from Pretoria, vegetables and nuts (Ghana), as well as legumes (Nairobi). The findings demonstrate that incorporating research on the least researched crops with successful integration of other research and development initiatives (policy and dissemination) can increase nutrition and improve dietary diversity. The nutrient gain will positively affect food security and nutrition, contributing to the achievement of Africa Agenda 2063, the United Nation's Sustainable Development Goals, and reducing food imports. The findings can inform research investment and decision across different institutions within the African continent. Research investment targeting crops such as finger millet, amaranthus, sweet potatoes, soya beans, and cashew nuts is needed considering the nutritional contribution, climate change adaptability, market potential, and biodiversity contribution. Further analysis should explore production, socio‐economic (marketability and income generation), and environmental gains (adaptive ability to climate change) for specific crops. The development of frameworks to guide the analysis of the nature and scope of factors affecting the contribution of these crops to food security and nutrition, as well as research on specific crops considering geographic distribution and institutional involvement, is also needed. [ABSTRACT FROM AUTHOR]