Location: Hard Winter Wheat Genetics Research
Project Number: 3020-21000-011-022-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 1, 2019
End Date: Aug 31, 2022
1. Fine-map the heat tolerance quantitative trait locus (QTL) on chromosome 3BS identified in the OK06114 x Wendy doubled haploid (DH) mapping population. 2. Identify QTLs for heat tolerance from the HV9W03-1596R x TX04M410164 mapping population.
We identified a major quantitative trait locus (QTL) for chlorophyll retention under heat stress on the short arm of chromosome 3B in a mapping population derived from US winter wheat lines OK06114 (heat tolerant) and Wendy (heat susceptible). We backcrossed donor lines that carry the 3BS QTL segment into Wendy and produced BC1F2 and BC1F2:3 seeds. The seeds will be phenotyped for heat tolerance and genotyped using KASP markers that are polymorphic for the 3BS region in this cross. This will allow us to identify which shortened recombinant segments carry the 3BS QTLs and which ones do not. This fine-mapping effort will allow us to significantly narrow the QTL region and identify the tightest flanking markers. The HV9W03-1596R (heat susceptible) x TX04M410164 (heat tolerant) mapping population consisting of 250 F8 lines has been GBS-genotyped and will be phenotyped by exposure for 16 days at 36C day and 30C night temperatures. Chlorophyll degradation and yield components will be measured. QTL mapping will be conducted for each of the measured traits to identify chromosome regions that control heat tolerance.