Nine varieties of soft spring wheat (Altayskaya 70, Altayskaya 75, Krasnoyarskaya 12, Novosibirskaya 15, Novosibirskaya 16, Novosibirskaya 29, Novosibirskaya 31, Novosibirskaya 41 and Svirel) were studied in the field experiment using fallow as a predecessor and wheat as a predecessor both with and without nitrogen fertilizer for an incidence of root infection caused by Fusarium spp., Alternaria spp. and Bipolaris sorokiniana. Average by varieties and variants of experiment incidence of Fusarium spp., Alternaria spp. and B. sorokiniana was 7.5, 5.7 and 10.8%, respectively. Wheat as a predecessor statistically significantly increased average by varieties incidence of both Fusarium spp. and Alternaria spp. in comparison with fallow. Nitrogen fertilizer statistically significantly increased average incidence of Fusarium spp., Alternaria spp. and B. sorokiniana. The incidence of fungal root infection and the effects of predecessor and fertilization statistically significantly depended on the variety.