Validation of Fusarium head blight markers in Triticum aestivum breeding populations

With quantitative disease resistance, it is difficult to know which loci of a resistant source are passed to progeny that are subsequently used as parents in further crossing. The objective of this study was to identify the Sumai 3 loci that contribute fusarium head blight (FHB) resistance in breeding populations which have Sumai 3 derived parents. Doubled haploid populations of Infinity/ND3085, Infinity/ND744, and Alsen/Helios crosses were evaluated in FHB nurseries at Carman MB, Ottawa ON and Charlottetown PE in 2007 using a two replicate randomized complete block design of 80 lines per population plus parental checks. Percent incidence and severity of head blight, Fusarium-damaged kernels and DON accumulation were evaluated. DNA markers reported as associated with Sumai 3 FHB resistance at different loci were assessed on the parents and lines of each population. Statistical analyses were applied to marker and disease results to determine which loci contributed resistance. Resistance was expressed inconsistently across environments and across parents for particular loci. The results demonstrate the need to validate FHB resistance loci from Sumai 3 to determine which were passed to progeny that are subsequently used as parents (eg. Alsen) to efficiently apply marker assisted selection.