Modern agricultural systems that promote cultivation of a very limited number of crop species have relegated indigenous crops to the status of neglected and underutilised crop species (NUCS). The complex interactions of water scarcity associated with climate change and variability in sub-Saharan Africa (SSA), and population pressure require innovative strategies to address food insecurity and undernourishment. Current research efforts have identified NUCS as having potential to reduce food and nutrition insecurity, particularly for resource poor households in SSA. This is because of their adaptability to low input agricultural systems and nutritional composition. However, what is required to promote NUCS is scientific research including agronomy, breeding, post-harvest handling and value addition, and linking farmers to markets. Among the essential knowledge base is reliable information about water utilisation by NUCS with potential for commercialisation. This commentary identifies and characterises NUCS with agronomic potential in SSA, especially in the semi-arid areas taking into consideration inter alia: (i) what can grow under water-scarce conditions, (ii) water requirements, and (iii) water productivity. Several representative leafy vegetables, tuber crops, cereal crops and grain legumes were identified as fitting the NUCS category. Agro-biodiversity remains essential for sustainable agriculture.

The combined application of organic resources (ORs) and mineral fertilizers is increasingly gaining recognition as a viable approach to address soil fertility decline in sub-Saharan Africa (SSA). We conducted a meta-analysis to provide a comprehensive and quantitative synthesis of conditions under which ORs, N fertilizers, and combined ORs with N fertilizers positively or negatively influence Zea mays (maize) yields, agronomic N use efficiency and soil organic C (SOC) in SSA. Four OR quality classes were assessed; classes I (high quality) and II (intermediate quality) had >2.5% N while classes III (intermediate quality) and IV (low quality) had <2.5% N and classes I and III had <4% polyphenol and <15% lignin. On the average, yield responses over the control were 60%, 84% and 114% following the addition of ORs, N fertilizers and ORs + N fertilizers, respectively. There was a general increase in yield responses with increasing OR quality and OR-N quantity, both when ORs were added alone or with N fertilizers. Surprisingly, greater OR residual effects were observed with high quality ORs and declined with decreasing OR quality. The greater yield responses with ORs + N fertilizers than either resource alone were mostly due to extra N added and not improved N utilization efficiency because negative interactive effects were, most often, observed when combining ORs with N fertilizers. Additionally, their agronomic N use efficiency was not different from sole added ORs but lower than N fertilizers added alone. Nevertheless, positive interactive effects were observed in sandy soils with low quality ORs whereas agronomic use efficiency was greater when smaller quantities of N were added in all soils. Compared to sole added ORs, yield responses for the combined treatment increased with decreasing OR quality and greater yield increases were observed in sandy (68%) than clayey soils (25%). While ORs and ORs + N fertilizer additions increased SOC by at least 12% compared to the control, N fertilizer additions were not different from control suggesting that ORs are needed to increase SOC. Thus, the addition of ORs will likely improve nutrient storage while crop yields are increased and more so for high quality ORs. Furthermore, interactive effects are seldom occurring, but agronomic N use efficiency of ORs + N fertilizers were greater with low quantities of N added, offering potential for increasing crop productivity.

Purpose: This study aimed to determine factors that increase resilience and cause smallholder farmers to adapt better to climate change and vulnerability. Design/methodology/approach: In this study, the authors used the vulnerability to resilience model and binary logit model to analyse the factors influencing household decisions to adapt. Findings: Households with increased access to climate information through extension services were likely to have better adaptation abilities. It was also shown that younger farmers were likely to adapt to climate change given their flexibility to adopt new techniques and their access and use of modern information and technology. Larger households were found to have higher probability of adapting as most adaptation strategies are labour intensive. Household’s possession of livestock and access to credit significantly enhanced adaptation. However, households with higher farm income have lesser incentives to adapt to because their current farming practices might already be optimum. Research limitations/implications: Given that most of the smallholder farmers are vulnerable, such as women-headed households and the elderly, who are labour constrained, there is need for research and development of labour saving technologies to increase resilience to climate change and vulnerability. Originality/value: These findings underscore the importance of enabling farmer access to information and better technologies which enable them to increase adaptive capacity and resilience.

Purpose: The purpose of this paper is to assess smallholder farmers’ vulnerability to climate change and variability based on the socioeconomic and biophysical characteristics of Chiredzi District, a region that is susceptible to the adverse effects of climate change and variability. Design/methodology/approach: Vulnerability was assessed using the Vulnerability to Resilience and the Climate Vulnerability and Capacity frameworks. Findings: The major indicators and drivers of vulnerability were identified as droughts, flash floods, poor soil fertility and out-migration leaving female- and child-headed households. From sensitivity analysis, it was shown that different areas within the district considered different biophysical and socioeconomic indicators to climate change and variability. They also considered different vulnerability indicators to influence the decisions for adaptation to climate change and variability. Originality/value: The results of this study indicate that the area and cropping systems are greatly exposed and are sensitive to climatic change stimuli, as shown by the decline in main cereal grain yield. These results also showed that there is a need to define and map local area vulnerability as a basis to recommend coping and adaptation measures to counter climate change hazards.