EN
The aim of study was to determine the impact of crop and the sprouting on the spread of alternaria on several cultivars of potato. The factors of the experiment were crop systems (integrated and organic) potato cultivars (Bila, Ania and Wawrzyn), treatments (seed sprouted and unsprouted). The rate of alternaria spread increased over time. A faster rate of the spread of alternaria was stated for non-integrated organic system of cultivation. The use of sprouting did not affect the expected reduction rate of alternaria spread. 50% infection of potato leaf surface, responsible for the yield accumulation was recorded in organic crop system 4–14 days earlier as compared to the integrated one.