Succinate dehydrogenase (Sdh) inhibitor fungicides, such as boscalid, are effective for the management of gray mold caused by the fungal pathogen Botrytis cinerea. Unfortunately, resistance to boscalid was common among isolates of the pathogen from small fruits grown in Oregon. Boscalid-resistance is commonly associated with mutations in Sdh, especially in...
Erwinia amylovora is a plant pathogenic bacterium that causes the destructive disease fire blight of apple and pear. We examined the plasmid content of a collection of 305 isolates of E. amylovora from Washington and Oregon with PCR assays and RFLP. Nearly all isolates of E. amylovora carried plasmid pEA29,...
Fire blight is a serious disease of apple and pear trees caused by the bacterium, Erwinia amylovora. This bacterium harbors a pathogenesis mechanism known as the Hrp secretory operon which induces some resistance genes and suppresses other resistance genes in the host plant following invasion. While previous researchers analyzed expression...
Blueberry stem galls in Pacific Northwest are often attributed to Agrobacterium tumefaciens. The disease also is associated with indole-3-acetic-acid (IAA) producing bacteria, as described on cranberry stem gall. Lack of studies makes it difficult to conclude whether these two types of bacteria could be the causal agent of stem gall...
Pantoea vagans C9-1 (C9-1) is a biological control agent sprayed onto apple and pear trees during bloom for suppression of fire blight, a devastating bacterial disease caused by Erwinia amylovora. Prior bioinformatics studies of C9-1 focused on predicted phenotypes associated with the three native megaplasmids, pPag1, pPag2, and pPag3, and...
Competitive exclusion has been the mechanism hypothesized to account for the biological control of fire blight disease of pear and apple by the bacterium Pseudomonas fluorescens A506 (A506). Recent laboratory assays demonstrated, however, that A506 produces an antibiotic that is toxic to the fire blight pathogen, Erwinia amylovora, when cultured...