Species diversity of root rot pathogens of apple tree of the genus Fusarium Link in Southern Russia

Abstract

For horticulture in the North Caucasus, and Southern Russia as a whole, root rot of fruit crops is a serious problem, especially in nurseries and young gardens. In recent years, the harmfulness of species of the genus Fusarium Link as pathogens of root rot in the apple tree of domestic Malus domestica Borkh has been increasing. As a result of the studies, 115 samples of seedlings from four examined regions of Southern Russia were studied, 264 fungal isolates were isolated, among which 11 species of the genus Fusarium were found. The composition and occurrence of species were heterogeneous at its various sampling points. So, in the industrial gardens of the Krasnodar Territory and Karachay-Cherkess Republic, species F. sporotrichioides Sherb. and F. oxysporum Schltdl. prevailed, in the Belgorod region - F. sambucinum Fuskel, in the Rostov region - F. sporotrichioides and F. proliferatum Matsush. The most common pathogens of rotting roots of apple seedlings in the entire studied sample were: F. sporotrichioides - 81 isolates, F. proliferatum - 37 isolates and F. oxysporum - 35 isolates. The rare species among the sample were F. avenaceum - isolates, as well as the pathogens that we isolated for the first time in the region as rot pathogens of F. solani (Mart.) Sacc. and F. poae (Peck) Wollenw.