Molecular mapping of QTL for fusarium head blight and fusarium damaged kernel resistance in spring wheat
Berraies, S., Cuthbert, R., Knox, R., Bokore, F., Henriquez, M.A., Burt, A., Kumar, S., Ruan, Y., Pozniak, C., N'Diaye, A., and Sharpe, A. 2016. Molecular mapping of QTL for fusarium head blight and fusarium damaged kernel resistance in spring wheat. 8th Canadian Workshop on Fusarium Head Blight, Ottawa. Novembre 20-22.
Fusarium damaged kernels (FDK), caused by Fusarium graminearum, causes downgrading and reduced quality. This study was conducted to identify DNA markers for Fusarium head blight (FHB) and FDK resistance in adapted spring wheat germplasm. From a cross between moderately resistant Carberry and moderately susceptible AC Cadillac, 774 doubled haploid lines were evaluated for response to FHB in nurseries near Morden and Brandon MB. From the continuous distributions of disease incidence (Type I resistance) and severity (Type II resistance), a 200 line subset of field resistant and susceptible phenotypes were evaluated for FDK (Type IV resistance). A linkage map of 2408 SNP (Infinium iSelect 90k SNP wheat array) and four microsatellite markers, was used to detect six significant Type I resistance QTL in both locations, eight significant Type II QTL in Brandon and five in Morden, and five significant Type IV QTL in Morden. Carberry carried favourable alleles for Type I, II and IV resistance on chromosomes 5A and 3B, Type I and II resistance on chromosome 7D and just Type II resistance on chromosome 3A. AC Cadillac contributed favourable alleles for Type I, II and IV resistance on chromosomes 3A, 2B and 4B, Type I and II on chromosomes 4A and 6B and only Type I resistance on 5A. These results indicate that the genomic regions contributing to reduced incidence and severity also contributed to a lower level of FDK. The QTL markers could be used to accumulate resistance loci in adapted wheat cultivars to lower FDK and improve quality.