EN
Numerous fungi occurring on oilseed rape cause losses of the seed yield. Causal agents of the incited disease are associated with plants for the whole season, but some of them can be observed only in specific phases of growth. In 2009 and 2010 in the spring time symptoms of infestation of oilseed rape by Typhula species were observed. The aim of the study was to define and identify the causal agents of snow mould of oilseed rape and its harmfulness to plants. It was the first attempt of describing Typhula genus on oilseed rape in Poland. Varieties of oil seed rape infected with Typhula spp. were examined. Field experiments were carried out in Wielkopolska region, Plants Breeding Station Borowo, Department Borowo Ltd., IHAR Group, and the Experimental Station of Testing Varieties Chrząstowo. The occurrence and harmfulness of the disease was strictly connected with the length of time of remaining snow cover on examined fields. The disease can be dangerous only locally and its occurrence is related to specific periods. It is possible that different varieties of oilseed rape are much more resistant to this pathogen than others.