Relevance. The presence of valuable biologically active substances, carbohydrates, organic acids and others in the eggplant fruits makes the culture one of the vegetables with the highest antioxidant activity. The VIR collection of eggplant includes 830 accessions from 70 countries of the world. The study of new acquisitions in the VIR collection presupposes a comprehensive assessment of the received material according to morphological, biological and economically valuable characteristics. The main objective of the study was to assess the variability of the biochemical parameters of egg-plant fruits in technical ripeness; as well as determination of the best accessions by the chemical composition of fruits and the content of biologically active substances.Materials and methods. The study of 19 accessions of eggplant accessions was carried out in 2020 in a winter greenhouse in Pushkin and Pavlovsk Laboratories of VIR (St. Petersburg). The morphological description of the accessions and the assessment for biological and economically valuable traits were carried out in accordance with the methodological guidelines and the VIR classifier. Biochemical analysis was carried out in the Department of Biochemistry and Molecular Biology of VIR in the phase of technical ripeness of fruits in terms of: dry matter content, sugars, total acidity, ascorbic acid, pigments and anthocyanins.Results. As a result of this study, the amplitude of variability in the content of dry matter (6.44- 8.68%), sugars (1.78-3.72%), ascorbic acid (5.92-21.08 mg/100 g), titrated acidity (0.10-0.31%), chlorophylls (0.52-15.13 mg/100 g), carotenoids (1.19-6.99 mg/100 g), β-carotene (0.11-0.52 mg/100 g) and anthocyanins (12.94-1031.40 mg/100 g) in eggplant fruits. Accessions with a high content of biologically active substances in fruits in technical ripeness were identified: Russian hybrids Bourgeois F1, Azhur F1; local accessions from Armenia: k-3156, k-3159, k-3161.

The experiments were conducted in 2015-2017 on the experimental fields of the Kazakh Research Institute of Potato and Vegetable Growing located on the northern slope of the Zailiysky Alatau, 40 km to the west of the city of Almaty, under irrigation conditions. The aim of the research was a comprehensive field assessment of selective onion samples with sterile cytoplasm from onion Galantum and their derivatives – varietal-linear hybrids obtained by pollination with domestic cultivars. Visual assessment, which was conducted on the background of natural disease infection, showed that 20 accessions of onions had a very weak susceptibility to peronosporosis (1-10% of leaves); 63 – weak susceptibility (11-25% of the leaves); 91 - average susceptibility (26- 50% of leaves); 118 – severe susceptibility (more than 51% of the leaves). As the results of the research showed, onion accessions differed significantly in terms of productivity: the gross yield varied from 13,3 to 83,6 t/ha, the commodity yields ranged from 10,6 to 78,3 t/ha, and the marketability ranged from 65,4 up to 98,8%. Yield level above 70 t/ha had breeding accessions with sterile cytoplasm from onion Galanthum: ON518, ON533, ON519 and ON516, amounting to 83,6; 75,3; 74,2 and 73,4 t/ha, respectively. Very high marketability of bulbs had breeding accessions ON171 – 98,8%, ON439 – 97,6% and ON158 – 96,8%. The value of storage losses varied depending on the genotype of the selected onion breeding material. The greatest physiological reduction in weight was observed in the accessions ON517 – 32,1%, ON516 – 26,5%, ON533 – 24,2% and ON336 – 17,7%, and the lowest - in the accessions ON431 – 4,6%, ON486 – 4,0% and ON327 – 3,4%. The correlation analysis showed a weak relationship between the parameters of the onion yield and its storabilioty (R = -0,10-0,24). Storability was mainly due to the physiological reduction in weight (R = -0,59), bulb soft rot (R = -0,59) and bulb sprouting (R = -0,69).

The investigations were conducted on the fields of the Kazakh Research Institute of Potato and Vegetable Growing located on the northern slope of the Zailiysky Alatau, 40 km to the west of Almaty city, under irrigation conditions. The soil of the experimental site is dark chestnut with medium-loamy structure. 37 carrot accessions with different geographic origins were the object of the study in the nursery of the initial breeding forms to evaluate their productivity and field resistance to foliar diseases such as Alternaria, Powdery Mildew. When symptoms expressed maximally 1.5 months before the harvest of carrot, visual assessment of leaf surface damaged by foliar infections was carried out according to the scale of infection, where 0 meant no damaged leaves; 1 meant very light damage (1-10% of leaves); 2 meant light damage (11-25% of leaves); 3 meant medium damage (26-50% of leaves); 4 meant severe damage (over 51% of leaves). The visual observation showed that two breeding accessions CR00655 and CR01253 had immunity to powdery mildew that maximally spread out over other carrot accessions approaching of 100% of damage of leaf surface with the score from 1.8 to 3.8 points, when disease developing from 45.0 to 93.8%. Alternaria spread on carrot plants not very intensively, only 17% of plants in the nursery were hardly attacked at 0.1-0.4 points as scored. The correlation analysis showed the absence of any link between characteristics of productivity and damage parameters caused by foliar diseases at r=0,005-0,225.

Relevance. The main direction of breeding melon Bikovskaya cucurbits breeding experimental station – branch of the FSBSI FSVC is the creation of varieties with valuable economic characteristics, especially with resistance to bioand abiotic environmental factors. To meet the needs of commodity producers and the population, varieties are needed not only with high yields, but also attractive appearance, good taste qualities. Very important: the rich color of the bark background, the proportional shape of the fruit and the sweet juicy pulp.Materials and methods. The research was carried out in 2020–2022 at the Bikovskaya cucurbits breeding experimental station – branch of the FSBSI FSVC. The object of research is melon varieties created over the past five years. The Osen variety was used as a standard. The main method of selection work with melon is intervarietal hybridization followed by individual selection.Results. Melon varieties were evaluated according to valuable economic characteristics, 6 best varieties were identified in comparison with the standard. In terms of yield, 2 varieties were distinguished (16.3 t/ha and 17.3 t/ha); in terms of dry matter content, 2 varieties (19%); in terms of large-fruited 1 variety (6.0 kg); in terms of the bright color of the bark background, 1 sample (bright yellow).