Mapping a Quantitative Trait Loci for Fusarium Head Blight Associated with Resistance in Winter Wheat.

Mapping Quantitative Trait Loci for Fusarium Head Blight Resistance in Winter Wheat

Abdul Hashimi, and Guihua Bai*

Department of Agronomy, Kansas State University, Manhattan, KS 66506 and USDA-ARS, Hard Winter Wheat Genetics Research Unit, Manhattan KS 66506

*Corresponding author: Guihua Bai, guihua.bai@ars.usda.gov

Fusarium head blight (FHB) is one of the devastating wheat diseases in the world. It not only causes great yield losses, but also lowers grain quality due to mycotoxins produced by the pathogen Fusarium graminearum. Wheat FHB resistance is a quantitative trait and controlled by multiple quantitative trait loci (QTLs). To identify consistent QTLs for FHB resistance in a US winter wheat CI13227 and markers tightly linked to these QTLs for marker-assisted breeding, we developed a population of 177 double haploid (DH) lines from the cross between Lakin and CI13227. We used Illumina wheat 90K single nucleotide polymorphism (SNP) chips to genotype the population for construction of a SNP map and evaluated the DH population for FHB resistance in three greenhouse experiments from 2016-2017 by using point inoculation and one field experiment (2017) using grain pawn inoculation. QTL mapping found four QTLs on chromosomes 4B, 5AL, 7A, and 2D, which explained 8-17% of the phenotypic variation for FHB resistance in different experiments. The 4B QTL showed the largest effect and were consistently detected in three experiments. QTL on 5A explained 11-12% of the phenotypic variation and detected in two greenhouse experiments. Other two QTLs were detected in only one experiment. The QTLs on the chromosome 4B and 2D showed a high correlation with plant height, suggesting a polytropic effect of these QTLs. These QTLs can be pyramided with Fhb1 or QTLs from other sources to improve wheat FHB resistance.