Occurrence of Ustilago striiformis in Dactylis glomerata Seed Production Fields in Oregon

Abstract

Stripe smut, caused by Ustilago striiformis, is a common disease of grasses grown for turf, but quantitative information concerning its occurrence in grass seed production fields is lacking. In 2004, 2005, and 2006, stripe smut was detected in 16, 17, and 3 out of 51, 42, and 33 Dactylis glomerata (orchardgrass) seed production fields surveyed in western Oregon, respectively. Stripe smut was not previously known to occur in these fields. The percentage of plants per transect with stripe smut in 2004, 2005, and 2006 ranged from 0 to 12, 0 to 4, and 0 to 1, respectively. In additional surveys during 2004-2006, to determine whether stripe smut was also occurring in seed production fields of other grasses in western Oregon, stripe smut was found in one field of Agrostis stolonifera, but was not detected in fields of Agrostis castellana, A. capillaries, Festuca arundinacea, F. longifolia, F. ovina, F. rubra subsp. commutata, F. rubra subsp. rubra, or Lolium perenne. Accepted for publication 9 July 2007. Published 23 October 2007.