First report of bacterial wilt on ryegrass

Bacterial wilt, which is caused by the bacterium Xanthomonas, strikes fear in the hearts of superintendents who manage poa greens. A related disease, bacterial decline, is caused by a different bacterium (Acidovorax), and attacks bentgrass greens. The fear stems from the fact that there are no effective chemical controls for this pathogen, though the product Daconil Action (chlorothalonil plus acibenzolar) may be able to suppress at least some symptoms.

Until very recently, we thought that perennial ryegrass was safe from…