Fungal gene expression patterns during infection of field pea roots by F. graminearum and F. avenaceum

Fusarium root rot of field peas has been a growing concern in the Midwestern production areas. Surveys conducted over the past three years demonstrated that species such as F. avenaceum and F. graminearum, previously associated with cereals in the U.S., were infecting roots of this major rotational crop. Information regarding the infection of legumes by these species is limited and our goal is to elucidate the mechanism of disease development through genomic analysis and pathogenicity studies. Fungal gene expression during infection of field pea roots by these two pathogens was evaluated as a part of this study. Over eleven thousand F. graminearum genes were detected, 6.57% of which are considered to be associated with cell defense, rescue and virulence. Initial comparisons suggest that 1606 F. avenaceum genes identified are similar to those expressed by F. graminearum during pea root infection. Genes common between crown rot and head blight in wheat and those associated specifically with crown rot were identified in this study in addition to genes involved in the trichothecene biosynthetic pathway. Analysis of fungal gene expression patterns, the ability of F. graminearum to produce mycotoxins on peas and their potential role in infection of this host will be presented.