The fungal complex that causes root rot in the plants, including common winter wheat, is very labile to pedoclimatic conditions, which is why it is quite difficult to make exhaustive conclusions about the diversity and dominance of the species with a decisive role in the development of the disease. Our research carried out in the dry 2022 year, demonstrated that the composition of fungal species isolated from the base of the stem of vigorous plants and weak plants with signs of disease is quite different. Thus, fungi with pronounced pathogenicity were isolated with a higher frequency from vigorous plants – Fusarium oxysporum, F. solani, F. culmorum, F lateritium, and from weak plants – fungi with more pronounced saprophytism – F. equiseti, F. sambucinum, Nigrospora maydis, Alternaria alternata. It should be noted that in vigorous and weak plants the diversity of fungi was 2,25 and 2,40, respectively, the dominance returning to the species F. oxysporum (0,35) and F. equiseti (0,31), respectively. The data demonstrate that more sensitive wheat plants accumulate more fungal species with pronounced saprophytes, which provides opportunities for advanced intrapopulation competition for these fungi and the emergence of new virulences.