Genomics-Assisted Breeding for Drought Tolerance in Wheat (Triticum aestivum L.): Recent Advances and Future Prospects

Abstract

Drought is one of the major abiotic limitations to wheat production worldwide, and the impacts of drought are worsened due to climate change. Drought tolerance consists of many genes with complex physiological and molecular processes, along with strong interactions between genotypes and environments; therefore, traditional phenotypic selection has produced minimal improvement to date. In this review we summarize recently published work (2020-2025) on genomics-assisted methods used to develop drought tolerance in bread wheat (8; 2). QTL mapping and marker-assisted backcrossing has allowed for successful validation of drought-related loci and their transfer into elite lines (3; 7). In addition, the coupling of genome-wide association studies with high-throughput phenotyping and genomic selection have improved predictability of grain yield in water-limited environments (5; 11). Overall, transcription factors from the DREB, NAC, MYB, and WRKY families are still considered the primary regulatory targets, but CRISPR/Cas-based gene editing is now able to provide precise, multiplex gene modifications in polyploid wheat (1; 10). The combination of pan-omics (the study of all omes), gene editing, speed breeding, and predictive modelling provides a realistic approach to developing climate-resilient, high-yielding cultivars. However, the rates at which phenotyping can occur and the speed at which candidate loci can be functionally validated are still the rate-limiting steps on this path (4; 6).