AUTHOR=Tomar Vipin , Singh Daljit , Dhillon Guriqbal Singh , Singh Ravi Prakash , Poland Jesse , Joshi Arun Kumar , Singh Pawan Kumar , Bhati Pradeep Kumar , Kumar Suneel , Rahman Mokhlesur , Tiwari Budhi Sagar , Kumar Uttam TITLE=New QTLs for Spot Blotch Disease Resistance in Wheat (Triticum aestivum L.) Using Genome-Wide Association Mapping JOURNAL=Frontiers in Genetics VOLUME=11 YEAR=2021 URL=https://www.frontiersin.org/journals/genetics/articles/10.3389/fgene.2020.613217 DOI=10.3389/fgene.2020.613217 ISSN=1664-8021 ABSTRACT=

Spot blotch disease caused by Bipolaris sorokiniana is a major constraint for wheat production in tropics and subtropics. The introgression of spot blotch resistance alleles to the disease susceptible lines is critical to securing the wheat production in these regions. Although genome-wide association studies (GWASs) for spot blotch were attempted earlier, the present study focused on identifying new quantitative trait loci (QTLs) for spot blotch under natural disease pressure in diverse field conditions. A total of 139 advanced spring wheat lines were evaluated in three environments (three years and two locations) in India and Bangladesh. The GWAS using 14,063 polymorphic genotyping-by-sequencing (GBS) markers identified eight QTLs associated with spot blotch disease resistance belonging to eight chromosomes across the wheat genome. Here, we report the identified marker–trait associations (MTAs), along with the allele effects associated with the disease. The functional annotation of the significant markers identified NBS-LRR, MADS-box transcription factor, and 34 other plant-related protein families across multiple chromosomal regions. The results indicate four promising new QTLs on chromosomes 1A (497.2 Mb), 1D (89.84 Mb), 2B (421.92 Mb), and 6D (6.84 Mb) associated with several disease resistance protein families. These results provide insights into new genomic regions associated with spot blotch disease, and with additional validation, could be utilized in disease resistance breeding efforts in wheat development.