Effects of dwarfing genes on water use efficiency of bread wheat

Climate change has increased the risk of drought, which significantly limits plant productivity.Various ways of increasing water availability and sustaining growth of crop plants in drought-prone environments are available. Genetic advances in grain yields under rainfed conditions have been achieved with the introduction of dwarfing genes. A thorough understanding of the effects of different dwarfing genes on root growth, coleoptile length, grain yields and water using efficiency(WUE) will provide opportunities to select appropriate Rht genes for breeding high WUE and grain yield cultivars. This review focuses on the mechanism involved in Rht genes that reduce plant height and affect root and coleoptile length, their consequent effects on grain yields and WUE, and suggests that for rainfed and irrigation-limited environments, combining GAR and GAI dwarfing genes in breeding may help boost WUE and yields, and more materials from different parental sources should be collected to assess opportunities for potential comprehensive application of specific Rht genes.