Abstract:

A new test (cucumber cotyledons spray inoculation test) of fungitoxicity of fungicide to Botrytis cinerea was established through inoculation on cucumber cotyledons with conidial suspension of B. cinerea amended with 1% yeast extract, 2.5% glucose and 10% carrot juice. The results showed that the test exhibits high disease incidence and uniform disease severity, good repetition and simple operation. Inhibitory activity of tebuconazole, mancozeb and iprodione to Botrytis cinerea was tested and compared by cucumber cotyledons spray inoculation test, mycelial growth rate test and conidial germination test, it was found that a high correlation was shown between the logarithmic concentrations of fungicide and probability values of inhibition rate,the correlation coefficients were all above 0.95.This method could be used in fungicide sensitivity test and screening resistance level of fungicide against Botrytis cinerea.