Pathogenicity and host range of Fusarium species associated with pea root rot in Alberta, Canada

Abstract

Root rot is a concern in the pea growing areas of Canada and elsewhere in the world, since it can cause significant yield loss. Fusarium spp. are considered major pea root rot pathogens. In this study, the pathogenicity and host range of Fusarium species collected from earlier surveys of commercial pea fields in Alberta were evaluated. Forty-five isolates belonging to six Fusarium species were selected for pathogenicity testing under greenhouse conditions. Fusarium solani f. sp. pisi and F. avenaceum were the most aggressive species, followed by F. oxysporum, F. culmorum and F. redolens. Due to their ability to cause severe disease on pea, F. solani f. sp. pisi and F. avenaceum were chosen for further testing on other common rotational crops grown in Alberta, and 10 cereal, oilseed and pulse crops were inoculated with isolates of those species. Both F. solani f. sp. pisi and F. avenaceum caused significant disease symptoms on pea, chickpea, dry bean and faba bean, but not on cereal crops, soybean, green lentil or canola when compared with their respective non-inoculated controls. Fusarium avenaceum, but not F. solani f. sp. pisi, caused significant root rot symptoms on red lentil, although disease severity was low. New information on the host range of these root rot pathogens will be valuable for choosing appropriate disease management strategies.