Genetic Aspects of Drought Resistance in Polyploid Plants by the Example of Wheat Triticum aestivum L

Plant drought resistance is a complex quantitative trait that depends on a lot of genes. By the example of allohexaploid wheat ( Triticum aestivum L.), we have described approaches to investigating the mechanisms of drought resistance in polyploid plants and their genetic and genomic architecture ranging from quantitative trait locus (QTL) mapping on the chromosomes to transcriptome profiling and detection of stable haplotype blocks beneficial for crop capacity under different water supply. Analysis of functions of the identified candidate genes made it possible to interpret molecular events upon adaptation to drought and reveal adaptation strategies unique to individual cultivars and suggested a decisive role of transcription reprogramming in the course of adaptation. Control over genes’ expression functionally depends on their physical association; however, the effect of spatial organization of chromatin and coregulators of transcription on expression of the genes controlling key agronomic traits of agricultural crops is still poorly investigated. The understanding of the expression of homoeologous genes participating in adaptation to water deficit is also limited.