The research was conducted to study the growth and development characteristics of the S. sclerotiorum fungus sclerotia isolated from winter rapeseed and white mustard plants in the Western Ciscaucasia region in order to develop the most effective measures to protect sowings of these crops from disease. The experiments were conducted in laboratory conditions in 2024. The object of the research was sclerotia of the S. sclerotiorum fungus, collected in 2023 from the infected stems of the white mustard variety Raduga (Labinsk district) and in 2024 from the infected stems of the winter rapeseed variety Loris (Krasnodar). The experimental design included four variants, each studying ten S. sclerotiorum sclerotia, using either a semi-synthetic PGA (potato glucose agar) nutrient medium or a synthetic Czapek’s nutrient medium, at air temperatures of 25 and 27°C. It is preferable to study the biological properties of S. sclerotiorum in laboratory conditions using the PGA nutrient medium. The germination rate of the pathogen’s sclerotia on PGA was, on average, 1.5 times higher than on Czapek’s agar at 25°C and 3.6 times higher at 27°C. Cultivating S. sclerotiorum isolates using Czapek’s agar slows the formation of new fungal sclerotia, reducing their number by 28–35%.
O. A. Serdyuk (Wed,) studied this question.