Relevance. Trophic relationships along with competition and mutualism are the most basic and significant interactions in ecosystems. To develop, survive, and multiply, insects need to consume a certain amount of nutrients at a certain ratio. Food products are complex mixes of nutrients and non-nutritive substances (sometimes toxic ones): macronutrients (proteins, carbohydrates, and lipids), micronutrients (vitamins and minerals), and water. Some nutrients are essential; insects lack the ability to synthesize them in their bodies and must obtain them from their diet or through symbiosis with beneficial organisms. Identification mechanisms being well developed in the system “phytophagous insect – plant” allow insects to successfully spread, multiply, and feed on certain plant species. The complex of hydrolytic enzymes in the insect intestine is one of the main targets for plant defense responses because these enzymes determine the availability of structural compounds for phytophagous insects. For this reason, enzymes in the insect intestine play a key role in the adaptation of insects to the pest resistance of fodder plants. For instance, when proteinase inhibitors are synthesized in a fodder plant as the result of induced insect resistance the complex of enzymes in an insect intestine might change negating the effect of these inhibitors. The development of co-adaptations due to interactions among species in food chains depends on a complicated constellation of conflicting relationships between consumers and food objects. The mechanisms of this influence may be rooted in the allelochemical interactions in the system “phytophagous insect – plant recipient”. Allelopathic interactions are among the most complex interactions because they are constituted by direct and indirect effects. Plants when damaged by phytophagous insects activate defense responses, which incorporate several mechanisms, including an increase in the concentration of secondary metabolites, many of which are phenolic compounds.The aim of the work is to describe the mechanisms of relationships in the system “phytophage-plant”. Conclusion. Management of processes of intra-water divergence of insect-phytophages in agrobiocoenoses in order to prevent the emergence of races and populations of pests adapted to live on initially resistant to them plant forms is possible in compliance with the transition to a targeted selection of agricultural crops for resistance to a complex of pests.

Relevance. Pepper is sensitive to chilling temperatures in all growth stages and low temperatures are main factors affecting plant growth, fruit growth and development and productivity. Evaluation and identification low temperature (LT) tolerant pepper genotypes at different growth stages is actual in breeding program for developing new cultivars. In present study we investigated the effect of the leaf cold damage within 25% (LCD) after chilling treatment in seedling stage on vegetative and reproductive traits of pepper accessions with different cold tolerance.Material and methods. In this study two pepper accessions “PE-J-2” and “Neokgwang” selected as chilling tolerant and susceptible in juvenile stage (3-4 true leaf stage), were used respectively. The seedlings of the selected pepper accessions with 25% visual cold damages of leaf green part (become lightly yellowed-whited or desiccated-dried) and control non-treated (NT) were grown in a glasshouse condition (D/N 30-32/22-24°C) for 10 weeks to evaluate the effect of LCD on pepper accessions vegetative and reproductive parameters after chilling pre-treatment. In pepper plants the vegetative parameters such as plant height (PH), leaf length (LL) and width (LW), number of internodes (NI), length of main axis (LMA), plants fresh weight (PFW) and roots fresh weight (RFW), and reproductive the number of flowers (NFL) and fruits (NFR), fruit set ratio (FS), fruit length (FL) and diameter (FD), total yield per plant (TY) were measured. The experimental design of this study was completely randomized. Statistical analysis was performed using the SAS Enterprise Guide 7.1 (SAS Institute Inc., Cary, North Carolina, USA).Results. According to the research result several accessions were identified: the accessions screened in juvenile stage as cold tolerant cannot always manifest good some agronomical traits performance at growth stages and it may range depending on the genotype specific features. The seedlings with LCD within 25% may significantly affect the vegetative and reproductive parameters of pepper plants. The phenomenon was recorded more distinctive in the correlations between some vegetative and reproductive parameters among NT and LCD plants.

A brief description  of weather  conditions  in 2012 is shown in the areas of pea production.  The reaction  of pea varieties of VNIIS, SOK breeding   at growing  in  different  regions   of  Russia  and Belarus is described.  The results of the meetings and the work, shops  with the leaders  of a number of canning plants are summa, rized.

Relevance. Tomato (Solanum lycopersicum L.) is one of the most important vegetables in the world. Every year the number of identified viruses and diseases increases, infection with which causes significant crop losses and significantly worsens the quality of agricultural products, especially in tomatoes.   Material and methods. In the present study we compared the growth of the vegetative and reproductive traits of tomato plants ‘Dokia’, ‘TY Red 250’ and ‘Pilabi’ grated onto bacterial wilt (caused by Ralstonia solanacearum) and Fusarium wilt (Fusarium oxysporum) diseases tolerant rootstock “Spider” (Takii seed, Japan). The non-grafted (control - CT) and grafted tomato plants (GR) were transplanted on 4 March of 2021 to the four season (vinyl) greenhouse on substrate perlite (mixture of perlite no. 1 and no. 3) and cultivated until September 20.   Results. The results showed that responses of the tomato cultivars to grafting combination was different, where agronomical traits depends on the each cultivar’s features can be ranged. The reduction of the values of stem diameter (SD), leaf length and width (LW), fresh fruit weight (FFW), fruit diameter (FD), fruit pericarp thickness (FPT) and fruit hardness (FH) with aging of plants and rising ambient temperature was detected. However, fruit soluble solids among all cultivars regardless of treatments were slightly increased. The index of fruit yield per truss (FYT) significantly decreased among all cultivars after 10th truss regardless of the treatments when the daily temperature increased from July to August. In grafted tomato ‘TY Red 250’ were identified the highest fruit yield per plants (FYP) than in CT plants, whereas in other tomatoes did not found similar differences between CT and GR plants.