Frost tolerance, resistance to Microdochium nivale and associated biochemical changes were investigated in leaves and crowns of six winter rye inbred lines. Investigated lines differed in their susceptibility to snow mould but not in frost tolerance. It was shown that winter rye resistance is linked to defence response in crowns expressed by higher activity of antioxidant enzymes – CAT, SOD and total peroxidases – on the 1st day after inoculation and β-d-glucosidase activation during the course of pathogenesis. It could be postulated that changes in leaves are attributed to reaction to cold while changes in crowns are attributed to pathogen reaction.