<i>Botrytis</i> tolerance to 6phenylalphapyrone and massoialactone

Abstract

The potential for Botrytis populations exposed to UV radiation to develop tolerance to the Trichoderma metabolite 6pentylalphapyrone (6PAP) and the 6PAP analog massoialactone was determined using 14 different Botrytis isolates There was significant isolate variation in germination of Botrytis conidia after UV exposure Plating conidia onto sublethal doses of 6PAP yielded no 6PAP tolerant mutants After UV irradiation two Botrytis mutants grew on normally lethal doses of 6 PAP while 59 mutants grew on normally lethal doses of massoialactone 6PAP mutants were cross resistant to normally lethal doses of massoialactone whereas massoialactone mutants were not able to grow on normally lethal doses of 6PAP After one generation of growth on kiwifruit slices 6PAP mutants lost tolerance to normally lethal doses of 6PAP However after three generations of growth on kiwifruit slices 6PAP plus massoialactone mutants retained tolerance to normally lethal doses to massoialactone