The paper presents research data of lipid peroxidation and lectin activity in wheat seedlings at seed treatment with solution of metal nanoparticles (Zn, Ag, Fe, Mn, Cu) and sole solution of copper nanoparticles under the high pathogen infection background of Pseudocercosporella herpotrichoides (Fron) Deighton (synonym: Oculimacula yallundae (Wallwork & Sponer) Crous & W. Gams). It was shown that investigated nonionic colloidal solutions of biogenic metals have the antioxidant effect through the inhibition of the synthesis of lipid peroxidation products. The increase of lectin activity levels during the early plants ontogenesis stages was observed in wheat seedlings infected with pathogen pre-treated with the mixture of metal nanoparticles.

The paper covers the study of the effects of silver (Ag) and copper (Cu) nanoparticles on wheat—Pseudocercosporella herpotrichoides pathosystem in general and, separately, on their interaction both with the plant and with the pathogen. Plants, treated with nonionic colloidal solutions of biogenic metal nanoparticles of Ag and Cu, have taken seed treatment as stress and have demonstrated the same changes in the dynamic patterns of thiobarbituric acid reactive substances (TBARS) content as a seedling infection or in its combination with a nanoparticle treatment. The wheat variety, which is sensitive to pathogen action, has showed a substantial (100%) increase in the TBARS contents, while the other varieties has shown lesser (40%) changes in the TBARS content as compared to the control. Besides, both silver and copper nanoparticles have not affected the growth and development of P. herpotrichoides, thus suggesting that the effect of nanoparticles is determined by the plant’s responses to the pathogen rather than the phytotoxic action of the copper or silver nanoparticles, at least during the initial stages of the pathological process.

The dynamics of expression of protective proteins (lectin and defensin) genes of different genotypes of the winter wheat, affected by P. herpotrichoides, was investigated. Methods. RT-PCR was used for gene expression analysis. Results. We established that the lectin mRNA content in control and infecting plants of the resistant cultivar is considerably higher than in the susceptible one; the character of defensin mRNA accumulation in the investigated cultivars, control and infecting plants, does not change. Conclusion. The spare pool of lectin mRNA in the resistant cultivar is more substantial, than in the susceptible one, that is, possibly, one of the factors of the plant resistance. Inability to support constantly a high level of the protective genes expression seems to influence negatively on the cultivar resistance .

Forests perform essential ecological functions -water protection, sanitation, health, recreation, and aesthetics. The research aimed to substantiate the ecological and economic importance of forest resources in the Kyiv region and analyse their rational use and protection. The article shows that the Kyiv region belongs to the regions with an average level of forest cover -592.8 thousand hectares or 22.2%. The level of forest cover is uneven in the area of the Kyiv Forest zone. It is 44%, and in the area of the Forest-Steppe, it is much lower and decreases from north to south. The use of forest resources in the Kyiv region in 2019 amounted to harvesting liquid wood of 999.5 thousand m 2 , and deforestation was carried out on 75.5 thousand hectares. The region's volume of forestry works and services amounted to 8,9 million dollars, and the wood stock makes 90805,9 thousand m 2 . Emphasis is placed on the importance of protecting the Red Book species of plants and fungi that grow in the forests of the Kyiv region. Examples of harmful economic activity in the areas belonging to the nature reserve fund and large-scale fires in April 2020, which covered more than 3.5 thousand hectares of forests in the region and caused damage to forest fauna and flora. The studied region's positive environmental and economic factors have been admitted by planting trees on an area of 2151 hectares and sowing seeds of forest species on an area of 67 hectares in 2020.

Plants are natural sources of bioactive compounds, and the intensive use of wild plants to obtain them, in particular secondary metabolites, depletes natural biocenoses. Instead, modern biotechnological methods, especially cell and tissue culture in vitro, make it possible to get environmentally friendly, highly productive plant raw materials that are able to synthesize and accumulate specialized substances, which are valuable for pharmacology, cosmetology, and medicine. Regenerating in vitro-plants of different plant species such as Acorus calamus L., Phalaenopsis sp. were obtained in our research. It was proved that by changing the cultivation conditions it is possible to change the content of substances of secondary metabolites in explants and in the nutrient medium under aseptic culture.