Accelerating Breeding for Drought Tolerance in Sorghum (Sorghum bicolor): An Integrated Approach

Abstract

Sorghum (Sorghum bicolor) is the main food crop for people living in marginal areas. They are faced with a number of production challenges including; drought, insect pests, diseases, soil fertility and striga weeds. To adapt to current and future stresses, there is a dire need to develop tolerant cultivars using multistress lines and varieties from wide genetic backgrounds. Toward better integrated approaches; we conducted participatory field screening in hot spot locations for drought, striga weed and major leaf spot fungal diseases on the 20 lines making mini-core sorghum germplasm. Lines carrying key traits of resistance to stresses have been recycled into the breeding program. The study also identified biochemical traits that could potentially be used as surrogate traits for the selection of tolerant genetic resources with improved yields. Nuclear male fertile crosses have been derived for exploiting differences in the cytoplasm for enhancing resistance. It also integrated variability in phytochemicals and cytoplasmic resistance to develop multi-parent sorghum lines and populations possessing potentially favorable adaptive alleles. In conclusion; unique traits and breeding strategies for sorghum adapted to the dry lowlands have been identified to lay a foundation for a modernized and market-oriented sorghum breeding program to the advantage.