Genome-wide association for heat tolerance at seedling stage in historical spring wheat cultivars

作者：Muhammad Ibrar Khan, Zarnishal Kainat, Saman Maqbool, Ambreen Mehwish, Suhaib Ahmad, Hafiz Muhammad Suleman, Zahid Mahmood, Mohsin Ali, Abdul Aziz, Awais Rasheed, Huihui Li · 发表于：Frontiers in Plant Science · 年份：2022 · DOI：10.3389/fpls.2022.972481 · 被引用次数：41 · 研究领域：Wheat and Barley Genetics and Pathology、Genetics and Plant Breeding、Crop Yield and Soil Fertility

Increasing global temperature has adverse effects on crop health and productivity at both seedling and reproductivity stages. It is paramount to develop heat tolerant wheat cultivars able to sustain under high and fluctuating temperature conditions. An experiment was conducted to characterize 194 historical wheat cultivars of Pakistan under high temperature at seedling stage to identify loci associated with heat tolerance using genome-wide association studies (GWAS). A quantitative trait locus, TaHST1 , on chr4A was also characterized to identify the haplotypes at this locus associated with heat tolerance in wheat from Pakistan. Initially, the diversity panel was planted under control conditions (25°C/20°C day and night temperature) in a glass house. At three leaf stage, plants were subjected to heat stress (HS) by increasing temperature (40°C/35°C day and night), while one treatment was kept at control condition. After 7 days of HS, data were collected for seedling morphology. Heat stress reduced these traits by 25% (root weight) to 40% (shoot weight), and shoot biomass was largely affected by heat stress. A GWAS model, fixed and random model circulating probability unification (FarmCPU), identified 43 quantitative trait nucleotides (QTNs) on all chromosomes, except chr7B, were associated under both HS and control conditions. Thirteen QTNs were identified in control, while 30 QTNs were identified in HS condition. In total, 24 haplotypes were identified at TaHST1 locus, and m...