Regions of Chromosome 2A of Bread Wheat (Triticum aestivum L.) Associated with Variation in Physiological and Agronomical Traits under Contrasting Water Regimes

Abstract

Understanding the genetic architecture of drought tolerance is of great importance for overcoming the negative impact of drought on wheat yield. Earlier, we discovered the critical role of chromosome 2A for the drought-tolerant status of wheat spring cultivar Saratovskaya 29. A set of 92 single-chromosome recombinant double haploid (SCRDH) lines were obtained in the genetic background of Saratovskaya 29. The lines carry fragments of chromosome 2A from the drought-sensitive cultivar Yanetzkis Probat. The SCRDH lines were used to identify regions on chromosome 2A associated with the manifestation of physiological and agronomical traits under distinct water supply, and to identify candidate genes that may be associated with adaptive gene networks in wheat. Genotyping was done with Illumina Infinium 15k wheat array using 590 SNP markers with 146 markers being polymorphic. In four identified regions of chromosome 2A, 53 out of 58 QTLs associated with physiological and agronomic traits under contrasting water supply were mapped. Thirty-nine candidate genes were identified, of which 18 were transcription factors. The region 73.8–78.1 cM included the largest number of QTLs and candidate genes. The variation in SNPs associated with agronomical and physiological traits revealed among the SCRDH lines may provide useful information for drought related marker-assisted breeding.

Genomic regions of durum wheat involved in water productivity

“…This can be explained by the findings of Mathew et al (2019) who reported a root and shoot biomass association region on chromosome 1B. Further, Pshenichnikova et al (2021) found 53 QTL associated with physiological and agronomic traits under contrasting water supply. These findings may explain the importance of Q.ICD.11.…”

Novel PHOTOPERIOD-1 gene variants associate with yield-related and root-angle traits in European bread wheat

“…The short arm of chromosome 2A, where Ppd-A1 is located, is a hot spot for genes which have minor effects on multiple yield-related traits. Several previous genome-wide association studies have identified specific regions on chromosome 2A associated with quantitative trait loci (QTL) that influence both physiological and agronomic traits in wheat (Guo et al 2017 ; Shi et al 2017 ; Wolde et al 2019 ; Gahlaut et al 2019 ; Hu et al 2020 ; Kaur et al 2020 ; Pshenichnikova et al 2021 ; Ding et al 2022 ). Our analysis is based on the correlation of variants of Ppd-1 with agronomic traits without controlling for population structure in a set of cultivars with diverse genomic backgrounds.…”

Increase in grain protein and gluten contents of bread wheat by the introgression of a T. timopheevii segment into chromosome 2A

“…It is known that T. timopheevii is adapted to the ecological conditions of a humid cool climate (Wheats of the World, 1976). Previously, it was shown that a fragment of 2A chromosome of S29 contains a large cluster of QTLs associated with the physiological response to drought in the region of the centromere and the molecular marker Xgwm339 (Pshenichnikova et al 2021). This region is included in the introgression and may be relevant to reaction to water availability.…”