Sclerotinia sclerotiorum: Epidemiological Factors Affecting Infection of Greenhouse Aubergine Crops

A series of greenhouse cultivations of Aubergine plants were studied for a three‐year period which included the 1981—1982, 1984—1985 and 1985—1986 growing seasons to determine the number of infections produced by S. sclerotiorum and the plant organs infected. A time‐phase difference was detected between the discharge of air‐borne spores and the appearance of infections. The appearance of flowers, the plant organ most susceptible to infection, appeared to mark the end of the latent period and the beginning of infections. The distribution of the infections within the greenhouse was random for two of the three seasons studied and fitted a Poisson distribution (p < 0.01). Analysis of the tendencies of the number of infections and numbers of infected plants revealed a sigmoidal curve that was a function of the accumulated hours in which relative humidity was 80 % or more.