VIEW ARTICLE

Ecology and Epidemiology

Survival of Mycelia of Sclerotinia sclerotiorum in Infected Stems of Dry Bean, Sunflower, and Canola. H. C. Huang, Agriculture Canada Research Station, Lethbridge, Alberta, Canada T1J 4B1; G. C. Kozub, Agriculture Canada Research Station, Lethbridge, Alberta, Canada T1J 4B1 Phytopathology 83:937-940. Accepted for publication 17 March 1993. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1993. DOI: 10.1094/Phyto-83-937.

Stems of sunflower, canola, and dry bean infected by Sclerotinia sclerotiorum were collected from fields and tested for survival of the pathogen in the mycelial state under field and laboratory conditions. In two field tests during 1986 and 1987, mycelia of S. sclerotiorum in sunflower, bean, or canola stems did not survive the winter months (November–March) in southern Alberta when infected stems were buried in soil at a depth of 7 cm. Mycelia survived the winter if the stems were placed on the soil surface; however, the survival rate was reduced to less than 69% after 4 mo (winter) and decreased rapidly during the spring. In laboratory experiments, mycelia of S. sclerotiorum in diseased stems survived longer at –10 C than at 20 C. Although the cold winter in southern Alberta favors survival of S. sclerotiorum mycelia, the study indicates survival of mycelia was too low for them to be a significant potential source of pathogenic inoculum.