Bacterial Sheath Rot of Wheat Caused by Pseudomonas fuscovaginae in the Highlands of Mexico

Angular, blackish brown lesions, 10 or 20 cm in length, bordered with purple-black angular area 1-2 mm wide and showing a grayish center, were frequently observed on leaf sheaths of bread wheat, durum wheat, and triticale at the booting stage in the central highlands of Mexico, 2,249-2,640 m above sea level. Fluorescent, strictly aerobic bacteria identified as Pseudomonas fuscovaginae (based on their positive reaction for Kovac's oxidase and arginine dihydrolase but negative for esculin hydrolysis and nitrate reduction) were isolated from these lesions (...)