Pyrenophora graminea . [Descriptions of Fungi and Bacteria

Abstract

Abstract A description is provided for Pyrenophora graminea . Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Barley and other Hordeum spp. Also, occasionally, on oats, wheat and rye. DISEASE: Causes leaf stripe of barley. Severe seedling infection can cause stunting and post-emergence death, but symptoms are not usually apparent until later, when long, chlorotic or yellow stripes on leaves and sheaths appear. Most leaves of a diseased plant are usually affected. Dark brown streaks develop later in the stripes, which eventually dry out and cause leaf shedding. Ears may not emerge or be deformed and discoloured. Grain production by infected plants is severely restricted. GEOGRAPHICAL DISTRIBUTION: Widespread distribution; occurs in most barley-growing areas of the world. TRANSMISSION: Seed-borne (49, 1342) usually by mycelium in the pericarp. Perithecia are uncommon, but overwintering sclerotia on crop debris have been reported from Russia (42, 13). Secondary infection by conidia is apparently important only for floral infection and subsequent seed contamination.