Meeting the needs of agricultural production in seedlings of berry crops (black currant (black currant (Ribes nigrum L.), sea buckthorn (Hippophaë rhamnoides L.), edible honeysuckle (Lonicera edulis L)) propagated by green cuttings, requires a search for ways to increase the rooting rate of cuttings Substrates including peat, sand, sapropel with additives of ammonium nitrate were studied. Adding sapropel (pH of water 7.4) to the composition of peat (pH of water 3.0-4.1) + sand increased the rooting rate of green cuttings of berry bushes. Maximum rhizogenesis was observed in the peat + sand + sapropel variant of 20 t/ha. Anthropogenic loads change the biological parameters of substrates and soils. The results of assessing the biological state of substrates used to obtain cuttings of berry bushes in Siberia by the level of enzymatic activity are analyzed. The quality of substrates is analyzed by studies of oxidative and hydrolytic enzymes. It was found that in the options peat + sand + sapropel 20 t/ha and peat + sand + N30, peat + sand + sapropel 10 t/ha + N30 an increase in the activity indicators of urease and invertase enzymes begins. A stable level of activity of the catalase enzyme confirms the bioecological characteristic of the substrate that is optimal for rooting cuttings in the ratio of peat + sand + sapropel 20 t/ha.

The importance of Pestalotiopsis and Neopestalotiopsis species as pathogens of economically important plants is steadily increasing, while knowledge of their phytotoxic metabolites remains limited. Eighteen new strains of pestalotioid fungi were isolated from various plant samples that showed visible symptoms of disease. These strains were evaluated morphologically, and phylogenetic analyses of the ITS (internal transcribed spacer) and tub2 (beta-tubulin) gene regions were performed for genotyping. The isolated strains from Castanea sativa wood and nut were assigned to the species Neopestalotiopsis clavispora (six strain) and P. chamaeropis (one strain); four strains of Neopestalotiopsis, and one strain of Pestalotiopsis were not identified at the species level. Five strains isolated from coniferous trees, such as cypress and fir, were assigned to the species P. monochaeta, P. verruculosa, P. hollandica, and N. chrysea. A strain isolated from the Vaccinium uliginosum L. shoot was diagnosed as N. megabetaspora. The pathogenicity of strains was confirmed in vitro on coniferous shoots, Granny Smith apples, and leaves of C. sativa. The most pronounced phytopathogenic properties were demonstrated by strains isolated from C. sativa and a blueberry shoot compared to strains from coniferous trees. The dihydropyrans pestalotin and 7-hydroxypestalotin were identified in these strains, except for P. chamaeropis. The strains, isolated from cypress and fir, mainly produced a range of other metabolites. The extracts of the strains exerted a phytotoxic effect on lettuce root growth, suggesting that the metabolites may be involved in the virulence of the phytopathogenic fungi Pestalotiopsis s.l. Using the extract of Pes21 N. megabetaspora—the most active producer of pestalotins—we demonstrated that the necrosis area on the leaves of V. uliginosum L. and Rubus idaeus L. increased consistently with increasing metabolite concentrations. Purified pestalotin and 7-hydroxypestalotin inhibited lettuce root growth at a concentration of 500 μg/mL and stimulated it at a concentration of 100 μg/mL. This work provides important insights into the regulatory role of metabolites in fungus–plant interactions and serves as a basis for developing new strategies for the maintenance of plant resources.

Results of study of effect of herbicidal load on state of aerobic cellulosic microorganisms and value of microbial biomass of chernozem leached under conditions of forest-steppe are presented. A decrease in the number of aerobic cellulosic microorganisms in all versions with herbicidal treatment was found. The highest microbial biomass quantity is determined in soil under wheat. A week after treatment with herbicides, microbial biomass decreased under both cultures in comparison with control, indicating the sensitivity of the microbial community to these preparations and their toxic effects. The herbicides tested had a negative effect on soil microbocenosis and retain this effect a month after treatment. After application of herbicides, there is a short period of depression of microorganisms, which is restored due to the emergence of resistant mutant forms or due to the formation of enzymes that hydrolyze the drug.