Stalk and Leaf Necrosis of Onion Caused byErwinia herbicola

Abstract

A new foliar disease of onion (A. cepa) in the Cape Province of South Africa was characterized by rapid necrosis of seed stalks and leaves. A bacterium isolated from diseased stalks was identified as E. herbicola. Characteristic symptoms of the disease developed within 3-10 days when the organism was inoculated by needle injection into healthy flower stalks. The bacterium was isolated from artificially inoculated plants. This is the 1st record of E. herbicola as a pathogen of onion.