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Antifungal, morphological and cultural properties of the Siberian and Abkhaz strains of the medicinal basidiomycete Ganoderma lucidum (Curtis) P. Karst were studied. A group of strains characterized by high growth rates in vitro on agar media (7.3-8.0 mm / day) and plant waste from timber processing (3.3-3.9 mm / day) was found. All strains of G. lucidum exhibited antifungal activity against phytopathogenic fungi; the degree of phytopathogen inhibition ranged from 10 to 58 %. Basidial rootrot fungi Heterobasidion and ascomycete fungi Bipolaris, Alternaria, Fusarium are the most sensitive to the presence of G. lucidum. The cultures most effectively limiting the phytopathogen development in the group of fast-growing Abkhaz strains (antifungal activity ranged from 21 to 58%) were identified. The high antifungal activity of strains on lignocellulosic substrates allows us to consider them as promising biocontrol agents for reducing the number, primarily, of basidial phytopathogens.

A phytopathogenic complex of the genus Fusarium, common on 19 wheat varieties cultivated in Siberia, was investigated. It was found eleven fungal species in wheat grain (Fusarium avenaceum, F. culmorum, F. diversisporum, F. heterosporum, F. oxysporum, F.poae, F. sambucinum, F. incarnatum, F. sporotrichioides, F. tricinctum, Neocosmospora solani), with the dominant one being F. sporotrichioides (from 23 to 68 % of the total number of species). Seven species were found in the rhizosphere of wheat (F. avenaceum, F.incarnatum, F. oxysporum, F. sambucinum, F. sporotrichioides, F. tricinctum, N. solani), with the most common being F. oxysporum (up to 39 %) and F. sporotrichioides (up to 35%). Biotesting a mixture of metabolites in wheat seeds and seedlings revealed highly toxic species, namely F. sporotrichioides and F. oxysporum (a decrease of in vitro seed germination by more than 55 % and a prolonged inhibitory effect on seedling development). F. avenaceum, N.solani and F. culmorum are moderately toxic species. The greatest danger for the development of wheat fusariosis in Siberia in terms of the total frequency of occurrence, phytotoxic and phytopathogenic properties is represented by F. sporotrichioides.