Sorghum is an important staple food crop in drought prone areas of Sub-Saharan Africa, which is characterized by erratic rainfall with poor distribution. Sorghum is a drought-tolerant crop by nature with reasonable yield compared to other cereal crops, but such abiotic stress adversely affects the productivity. Some sorghum varieties maintain green functional leaves under post-anthesis drought stress referred to as stay-green, which makes it an important crop for food and nutritional security. Notwithstanding, it is difficult to maintain consistency of tolerance over time due to climate change, which is caused by human activities. Drought in sorghum is addressed by several approaches, for instance, breeding drought-tolerant sorghum using conventional and molecular technologies. The challenge with conventional methods is that they depend on phenotyping stay-green, which is complex in sorghum, as it is constituted by multiple genes and environmental effects. Marker assisted selection, which involves the use of DNA molecular markers to map QTL associated with stay-green, has been useful to supplement stay-green improvement in sorghum. It involves QTL mapping associated with the stay-green trait for introgression into the senescent sorghum varieties through marker-assisted backcrossing by comparing with phenotypic field data. Therefore, this review discusses mechanisms of drought tolerance in sorghum focusing on physiological, morphological, and biochemical traits. In addition, the review discusses the application of marker-assisted selection techniques, including marker-assisted backcrossing, QTL mapping, and QTL pyramiding for addressing post-flowering drought in sorghum.

Sorghum is an important food crop for people in drought-prone areas of the world. The production in Tanzania has been ≤1 t ha⁻¹ for a decade. The study was conducted in Iramba, Ikungi, and Kongwa districts to identify factors influencing the sorghum production, adoption rate, and strategies to address drought in Tanzania. The study involved 240 respondents for individual interviews and focus group discussions. Thirty respondents participated in individual interviews while ten farmers participated in the focus group discussion per village. Our study found that birds, poor soil fertility, and drought were the major constraints across the study districts. Drought tolerance, high yield, and early maturity were the most preferred traits by farmers across the study areas. Farmers addressed drought stress in sorghum by practicing early planting early maturing varieties in November and using drought-tolerant varieties. However, most farmers failed to name the diseases and pests affecting sorghum. This study highlights basic information for plant breeders to incorporate traits preferred by farmers in breeding programs when developing new sorghum varieties for sustainable production. The study shows the importance of involving farmers to identify the problems and solutions of sorghum production to increase the adoption rate.

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