Mapping Resistance QTL for Hessian Fly (Mayetiola destructor) in Hard Red Winter Wheat (Triticum aestivum L.) and Analyzing Hessian Fly Virulence in Texas

Abstract

The Hessian fly (Mayetiola destructor) is an important pest of wheat (Triticum aestivum L.) worldwide and of particular importance in Texas. The most effective control is integrated pest management beginning with resistant varieties of wheat. Hessian fly populations are genetically diverse and can rapidly become virulent to resistance genes that are widely deployed in a region. Discovering and confirming the location of resistance genes across wheat populations is important for wheat breeding and the use of marker assisted selection.

A biotype analysis was conducted in the northeastern and central Texas regions. This analysis showed that resistance genes H12, H13, H20, H21, H22, H25, H26, H28, H29, H32, H33, H34, and Hdic are highly effective in these regions. Texas fly populations have increased in virulence and are now considered the most virulent biotype L or vH3, vH5, vH6, vH7/H8, vH9, vH10, vH14, vH15, vH23, vH24, vH31, and vH35/H36.

Two recombinant inbred line (RIL) populations were phenotyped in the greenhouse and in five field year/locations in Texas in 2020, 2021, and 2022. The 217 RIL population (‘TAM 204’/‘Iba’) showed a major quantitative trait locus (QTL) from TAM 204 on 3BS explaining 27.4% of observed phenotypic variation (PVE). Minor QTL were mapped from TAM 204 in individual environments to chromosome 1AS (PVE of 9.2% and 14.3%), 4B (PVE 2.2%), 5A (PVE of 0.8%), and 5B (PVE of 6.4%). A major QTL from ‘Iba’ was mapped to 2D (PVE of 23.0%) with minor QTL mapped to 2B (PVE of 5.4%), 4B (PVE of 4.0%), and 5B (PVE of 10.2%). The same 2D QTL (QHf.tamu-2D.36) was also mapped to ‘Gallagher’, a sibling of Iba, with a PVE of 22.4%. The 186 RIL population (‘TAM 113’/Gallagher) showed two major QTL for Hessian fly resistance on 1AS with PVE values of 23.01% and 31.82%. An additional 5 QTL were mapped to 1AS. QTL were also mapped to 3B, 5A, and 2D.