Aggressiveness of Fusarium culmorum isolates for head blight symptoms is highly stable across four cereal crops

Abstract

AbstractFusarium culmorum is an important component of Fusarium head blight (FHB) in Northern Europe in all cereals. We analysed the stability of six isolates differing in origin by inoculating them on four winter cereal crops (bread wheat, durum wheat, triticale and rye) with two cultivars each across three years and used disease symptoms as aggressiveness trait. Isolates significantly differed in their aggressiveness, measured as mean FHB severity, as well as the resistance of the cereals (p ≤ .01). Within the crops, bread and durum wheat were the most susceptible and showed significant differences between cultivars, triticale and rye were much less affected. Isolate × cereal and isolate × cultivar interactions were not significant. Accordingly, the isolates showed a similar ranking for all cereals and cultivars. The nivalenol‐producing isolate FC60 was the least aggressive isolate. Despite large differences on the host side, aggressiveness was a stable, highly heritable trait in F. culmorum.