A review of the adaptive capacity of sweet sorghum to improve food security and poverty alleviation in sub-Saharan Africa

Abstract

• Sweet sorghum can address socioeconomic challenges for African smallholder farmers. • A neglected multiuse crop, it is utilised for food, fuel, fibre, and fodder. • This grain crop can grow under water limited- and low nutrient input conditions. • Adoption of sweet sorghum in smallholder farming requires investment in research. Current challenges facing smallholder farmers in sub-Saharan Africa (SSA) require holistic adoption of crops that have diverse socioeconomic and agronomic significance. Sweet sorghum, an underutilised grain crop, has such potential, especially for bioethanol production, due to its adaptation to harsh conditions. Despite being native to SSA, its neglect and underuse is a concern given its wide potential to improve socioeconomic conditions of farmers in this region. This review highlights sweet sorghum's potential by discussing its adaptive capability against major production constraints such as water availability, soil nutrition, plant population, planting date, and harvest time. The review highlights sweet sorghum as a crop that maximises its growth and development under water stress conditions due to its high-water use efficiency. Furthermore, sweet sorghum can be cultivated under marginal soils compared to its biofuel counterparts (e.g., maize, sugarcane, and sugar beet) and can still be high yielding (grain) at high plant densities, with early planting dates also resulting in high yields. These attributes are significant in smallholder farming systems due to their susceptibility to socioeconomical and agronomic challenges. In addition, it was identified that there is lack of research relating to pests and diseases that plague sweet sorghum, with some measures and recommendations being based on grain sorghum. Therefore, the need for research and development on sweet sorghum in SSA may not only intensify its benefits to farmers but can also improve efficient cultivation under local environmental conditions.