The studies conducted allowed us to establish that representatives of pathogenic mycobiota, developing on trees as consumers, intensify the processes of degradation and disintegration of weakened and unstable forest ecosystems. Pathogenic fungi have a significant negative impact on the differentiation of trees in the forest, on the processes of seed and vegetative reproduction of tree species. A comparative analysis of heavy metal content at different trophic levels (consumers and decomposers) in forest ecosystems with the participation of representatives of mycobiota was carried out.
Quantitative dynamics of mycorrhizal endings development of self-sown oak seedlings during one vegetative period on the laid sample plot was studied. The obtained data showed that the maximum number of mycorrhizae on the roots of oak self-seedlings is formed by the end of the vegetation period, and this pattern can be traced at all stages of recreational digression. It was found that in forest communities of the Ulyanovsk region self-seeded oak cherry exists in an oblique interaction with ectomycorrhizal fungi, which is expressed in the formation of ectomycorrhizae on the roots of plants, which are transformed into sucking roots of plants.