The Longevity of Conidia of Sclerotinia Fructicola (Wint.) Rehm Under Field Conditions

The longevity of conidia of S. fructicola was determined in an orchard environment. Less than 1 % of conidia remained viable after exposure or 8 days in the tree canopy. In addition to reducing viability, exposure reduced both germ tube length and infection of mature fruit. Conidia prepared in a suspension in sterile water, to simulate those that are dispersed in rain, lost viability more rapidly on exposure than conidia that remained dry. When conidia were in contact with unsterilized soil for 24 hr they also lost viability.