Association of fusarium head blight resistance with gliadin loci in a winter wheat cross

Fusarium head blight (FHB) is one of the major diseases of wheat (Triticum aestivum L.). Genetic control of resistance to Fusarium spp. has been studied in resistant Chinese spring wheat cultivars, but little is known about inheritance of lower but useful levels of resistance found in winter wheat. This study was undertaken to characterize the genetic control of FHB resistance and to identify possible associations of resistance with several marker loci in winter wheat. Recombinant inbred lines were derived from the cross of a susceptible winter wheat, F1054W, with a moderately resistant parent, Sincron, not related to the Chinese germplasm, The parents had different alleles: at five marker loci, RhtB1, Rht8, W2, GliB1, and GliD1. Recombinant inbred lines Il ere classified for alleles at the RhtB1 and Rht8 loci by plant height and seedling response to exogenous gibberellic acid. Alleles at the GliB1 and GliD1 loci were determined Front the gliadin spectrum detected by starch gel electrophoresis and alleles at the W2 locus by phenotypes in the field. The area under disease progress curve (AUDPC) and relative weight of inoculated spikes (RWIS), following injection of Fusarium graminearum Schwabe inoculum into central florets of flowering spikes, were determined for 3 yr in the field. A significant increase in resistance was associated with the allele GliR1, suggesting location of a Fusarium head blight resistance quantitative trait locus (QTL) on chromosome T1BL.1RS. A smaller but significant increase in resistance was associated with allele GliD1b, indicating the presence of another QTL on chromosome 1D, No association between Fusarium resistance and RhtB1, Rht8, or W2 was found. The effects of favorable alleles on chromosomes 1B and LD,were cumulative, Selection for genotypes possessing GliR1 and GliD1b in this population would increase the probability of obtaining lines with higher resistance to Fusarium head blight.