FUSARIUM HEAD BLIGHT RESISTANCE IN SPRING WHEAT CULTIVARS

Fusarium head blight (FHB), also called scab, caused by Fusarium graminearum was generally more severe in spring wheat cultivar Wheaton than in cv. Marshall, except in years when weather was excessively dry or wet during flowering and kernel-fill stages of plant growth. Fifteen wheat cultivars from the upper midwestern United States were evaluated in 1988, 1989, and 1990 for FHB resistance. FHB index (the percentage of spikelets infected in 50 spikes) was least in cv. Stoa each year. The FHB index varied with the other cultivars, but Wheaton was among the most severely infected, and Marshall was among the intermediate cultivars. The FHB index value was greatest in 1989 when rain favored disease development, least in 1988 when drought was severe, and intermediate in 1990. FHB incidence and severity did not differentiate cultivars as well as index values did. The FHB reactions of Chinese cultivars Fan 1 and Su Mai 3 were similar to those of Minnesota cultivar Marshall. Reactions of other Chinese cultivars were similar to those of susceptible Wheaton.