Genetic dissection of maize drought tolerance for trait improvement

Abstract

Maize is one of the most important crops, but its production is threatened by drought stress worldwide. Thus, increased drought tolerance has been a major goal of maize breeding. Conventional breeding strategies have led to significantly increase of maize yields; however, these strategies often fail to meet the need for drought stress tolerance enhancement. Here, we focus on progress related to the genetic dissection of drought tolerance in maize at different developmental stages achieved through linkage mapping and association mapping. Moreover, recent molecular breeding systems, including transgenic, genome-wide marker-assisted selection, and genome editing technologies, have provided a more direct, efficient, and accurate approach for trait improvement. We also provide perspectives on future directions regarding multi-omics studies and maize improvement. Overall, the application of acquired knowledge will facilitate maize breeding to meet the challenges.

Keywords: Drought stress; Drought tolerance; GWAS; Maize; Molecular breeding; QTL.

Fig. 1

Effect of drought stress on maize growth and development and the research strategy for the trait improvement. a An illustration describing the morphological changes that occur in plants in response to drought stress. b The physiological and cellular responses that occur in maize in response water-deficit conditions and lead to reductions in growth and yield. c Schematic of the research strategy employed in genetic dissection of maize drought resistance for trait enhancement