Association Mapping for Fusarium Head Blight Resistance in European Soft Winter Wheat

Fusarium head blight (FHB) caused by various Fusarium species is an destructive disease in wheat-growing countries causing yield losses and contamination with mycotoxins. Thus, wheat-breeding research efforts are bound towards producing FHB resistant varieties. In Europe, breeders favor the use of adapted genetic sources for resistance due to their better grain yield and quality. Thomas Miedaner and colleagues at Universität Hohenheim, Germany, conducted a study with the aim of identifying regions in the wheat chromosome that affects FHB resistance in 455 European soft winter wheat lines (Triticum aestivum L.) through mapping of the whole genome. All the lines were assessed for FHB resistance by inoculation in two environments and numerous ratings.

One hundred fifteen (115) simple sequence repeat markers were distributed to the whole genome and two specific markers to Rht-B1 and Rht-D1 genes. Genome-wide scan revealed nine significant relationships between the markers and the phenotype on seven chromosomes, which includes the dwarfing gene Rht-D1. To address the possible problem of multiple comparisons, the researchers applied the Bonferroni-Holm correction method; resulting to three significant associations on chromosomes 1B, 1D, and 2D, one of which was found to be modified with Rht-B1. Therefore, FHB resistance genes can be found in two regions of the genome specifically in chromosomes 1D and 3A, considering the effect of epistasis.

The research article published by the Molecular Breeding journal is available at http://www.springerlink.com/content/m29272w377j30020/.