Results summarize literature and experimental data on the content of glucose and fructose of different varieties in grapes belonging to different botanical species of Vitis. The ratio of glucose and fructose indicator can be used for fermentation control and prevention of under fermentation in the production of dry wines, as well as an identification parameter to assess the authenticity of grape juice and concentratedmust. The object of the study were grapes of red and white winemaking European and autochthonous varieties, belonging to Vitis, as well as varieties of new selection (Aligote, Albilio, Verdelho, Sersial, Rkatsiteli, White Muscat, Cabernet-Sauvignon, Bastardo of Magarach, Kephesiya, Ekim kara, Golubok). Sugar content in grape samples was inthe range of 180-260 g/l. Total hexoses were determined by HPLC method according to a modified methodology developed by the Department of Chemistry and Biochemistry of Wine of "FSBSI "Magarach ". It was established that the value range of the glucose-fructose index in the grapes cultivated in different viniviticultural regions of the world makes 0.74-1.19. It has been revealed that the glucose-fructose index decreases with the ripening of berries. Low index values are characteristic for the grape that ripens at high temperatures and was cultivated in regions with hot climate. High index valuesare characteristic of table grapes and winemaking grape varieties of the species Vitis labrusca, Vitis amurensis and interspecific hybrids. Within the botanical species we canidentify varieties that tend to accumulate higher volumes of either glucose or fructose. These patterns are equally characteristic of white and red grape varieties. The analytical analyzes of the Crimean winemaking grape varieties resulted in the establishment of the glucose-fructose index for the first time, varying within the range of 0.9-1.06.

Relevance. Currently, the priority direction in the development of the food industry is the use of local raw materials and the production of products with increased nutritional value, i.e. with an increased content of micronutrients, which include vitamins, minerals, macro and microelements. One of these products of plant origin is the pumpkin culture. The cultivation of high-yielding, versatile, nutrient-rich crops, such as pumpkin, plays an important role in ensuring food security. When breeding new improved varieties, special attention is paid to the adaptability of the crop to growing conditions, as well as to portion fruits with high taste and technological qualities.Purpose. Selection of the most adapted, productive, high-quality pumpkin samples for breeding and their cultivation in industrial production and the private sector in the conditions of the southern forest-steppe of Western Siberia.Material and methods. Field research was conducted in 2021-2022 at the experimental site of the selection (organic) crop rotation, in the educational and experimental farm of the Omsk State Agrarian University. Meteorological conditions during the years of the experiments were different, but quite typical for the climate of the southern forest-steppe of the Omsk region. The object of research are 5 varieties of large-fruited pumpkin: Dietary, Red etamp, Crumb, Honey crumb, Honey dessert; two samples of selection of the Omsk State Agrarian University: 1/15, 2/15; three samples of selection of the FGBOU IN RGAZU: 4/21, 5/21, 7/21. Observations, accounting and analysis were carried out according to generally accepted methods.Results. The biological yield of the studied cultivars varies from 10.3 to 42.2 t/ha in 2021 and from 18.2 to 35.8 t/ha in 2022.

Pumpkin fruits are the source of carbohydrates, mineral salts and vitamins during wintertime. The change of the biochemical compositions of pumpkin fruits depending on storage time has been studied. The results of chemical analysis revealed that during four months of storage the content of quality indicators increased followed by its reduction after five and more month of storage.