INFLUENCE OF INOCULUM PRODUCTION TEMPERATURE ON CARPOGENIC GERMINATION OF SCLEROTIA OF SCLEROTINIA-SCLEROTIORUM

Three isolates of Sclerotinia sclerotiorum, sun-87 from Alberta, Tai from Taiwan, and SS-12 from Florida, were compared for carpogenic germination of sclerotia produced on potato dextrose agar cultures incubated at 20-degrees-C for 14, 21, or 42 days. Sclerotia formed at 20-degrees-C could germinate carpogenically without a cold conditioning treatment and the level of germination was dependent on specific inoculum temperature requirements for isolate sources. The favorable inoculum temperature for carpogenic germination of daughter sclerotia formed at 20-degrees-C was 10-degrees-C for isolate sun-87, but 25 or 30-degrees-C for isolates Tai and SS-12. There was no difference in carpogenic germination of sclerotia from different inoculum types (mycelial mats or sclerotia) or of different culture ages (14, 21, or 42 days old.