EFFECT OF FUNGICIDE APPLICATION IN THE SOIL ON THE CARPOGENIC AND MYCELIOGENIC GERMINATION OF Sclerotinia sclerotiorum

Abstract

The effects of benomyl, procymidone, iprodione, vinclozolin, fluazinan and methyl thiophanate on the carpogenic and myceliogenic germination of Sclerotinia sclerotiorum sclerotia, in soil, were tested in gerbox. Three hundred grams of soil were placed in each gerbox and twenty five sclerotia were buried in each one at a depth of 2.0 cm. The fungicides were applied at a dose of 0.5 kg.ha^-1 i.a., in the soil, simulating a water depth of 6.0 m. In general, vinclozolin was the best treatment, with an efficiency of 100% in inhibition of stipes and apothecia. Fluazinan allowed the formation of ones unviable stipes, resulting in absence of apothecia. The myceliogenic germination of the sclerotia was observed after 15 days of incubation. Methyl thiophanate showed 75% efficiency in the inhibition of myceliogenic germination followed by procymidone and vinclozolin, with 60% efficiency on average. Benomyl, fluazinan and iprodione were least efficient in the inhibition of the myceliogenic germination of the sclerotia, not differing statistically from the control. After 30 days of incubation most fungicides did not differ significantly in the inhibition of the miceliogenic germination, but differed from benomyl and the control.

KEY-WORDS: Chemical control; white mold; Phaseolus vulgaris.