Scab Response and Deoxynivalenol Accumulation in Spring Wheat Kernels of Different Geographical Origins Following Inoculation with Fusarium culmorum

Twelve Polish spring wheat cultivars and 18 spring wheat accessions (nursery name 4th SRSN, CIMMYT) Mexico, were examined over a period of 3 years for components of resistance against Fusarium head blight (scab) by using the highly pathogenic, eoxynivalenol (DON)-producing isolate of fungus. Resistant wheat cultivars served as controls. The mean disease score (on a scale from 0–5) ranged from 0.6 to 2.2 for the CIMMYT lines and from 0.9 to 3.1 for Polish cultivars. Only in three CIMMYT lines the mean kernel weight per head corresponded to the observed in resistant cultivars. Two of these lines and an additional one had low disease scores as well as low DON accumulation. Univariate and multivariate analysis of variance showed significant differences between years and wheat accessions for all the traits. No correlation was observed between DON accumulation and both disease score of head and percentage of Fusarium damaged kernels (%FDK) in both CIMMYT and Polish spring accessions. This points to at least three different components of resistance: resistance to pathogen spread, to kernel colonization and to toxin accumulation.