Variation of Fusarium Head Blight Attack in Semidwarf Wheat Cultivars and Relationship with Stripe Rust Attack

Abstract

Fusarium head blight (FHB) is a major threat to wheat production worldwide. We studied the Type 2 resistance of nineteen winter wheat cultivars under artificial inoculation by injecting spores of two Fusarium isolates into central florets of spikes. Weather conditions and Fusarium isolates used for artificial inoculations strongly influenced Fusarium attacks, but we also observed significant differences between cultivars. Six semidwarf wheat cultivars carrying Rht-B1b allele had significantly lower average Area Under Disease Progress Curve (AUDPC) than other cultivars, including two taller cultivars. Three of the six best resistant wheat cultivars carried the 1A-1R translocation, suggesting a beneficial effect of this rye chromatin presence on reducing the Fusarium head blight attack. Presence of stripe rust attacks significantly increased the area under disease development curve for Fusarium head blight, demonstrating the importance of debilitating effects of other biotic stresses.