Effective imputation of
missing genotypes in low coverage skim-sequencing or reduced-complexity
sequencing projects is essential to identify potentially causal associations
and to build robust genomic selection (GS) models. The newly developed Practical
Haplotype Graph (PHG) tool presents this opportunity for wheat breeders to efficiently
store sequence data and accurately impute genotypes across the wheat genome. A first-generation wheat
PHG demonstrated over 92% imputation accuracy using very low (0.01x) exome
sequencing coverage depth, and imputation accuracy of 89% using GBS sequencing
technology. Our project builds on these results by creating a customized PHG
database with wheat exome capture sequence of 200 FHB resistant and adapted wheat
cultivars exhibiting different levels of resistance. These haplotypes will inform
imputation of lower coverage sequenced breeding lines with high accuracy. By incorporating FHB resistant varieties in the database
composition, FHB resistance-associated haplotypes are represented and will be used
for developing a GS model for FHB resistance, identifying
novel FHB resistant haplotypes/QTLs, and developing diagnostic markers for
these QTLs. I will describe the progress of this new bioinformatics platform in
wheat populations, and how it will be used to inform selection for FHB
resistant germplasm in US breeding programs.