Tolerance of Botrytis cinerea to iprodione and vinclozolin

SUMMARY Isolates of Botrytis cinerea Pers. ex Pers. from slow‐developing lesions on strawberries from plants treated with iprodione or vinclozolin fungicides were found to grow on potato dextrose agar (PDA) containing 10 000 p.p.m. iprodione or 1000 p.p.m. vinclozolin. At smaller concentrations, the presence of these fungicides sometimes stimulated growth of these tolerant isolates. When isolates of B. cinerea sensitive to iprodione and vinclozolin were placed on PDA containing between 1 and 5 p.p.m. of one of these fungicides, a few of the cultures showed mycelial growth after extended incubation for seven days. These cultures were also able to grow when subcultured on fresh PDA containing 5 p.p.m. of iprodione or vinclozolin.