Buckwheat is a source of a valuable food product, the preparation of which for food purposes imposes a number of quality requirements. The most important criteria for the quality of raw materials that affect the yield and quality of unground groats are the weight of 1000 fruits, evenness of fruits, high content of the kernel and ease of peeling. Due to the achievements of breeding, the size and weight of 1000 fruits of some modern varieties of buckwheat amounted to 30 g or more. In breeding for the technological properties of fruits in large-fruited varieties, the problem of optimizing the proportion of fruit shells and fruit fulfillment is relevant. Buckwheat as a food product is a source of biologically active compounds with antioxidant properties that improve the functional activity and health of people. Increasing the content of rutin in the selection process will increase the biological value of buckwheat. Therefore, it is important to combine in modern varieties the signs of increased productivity with the qualitative characteristics of the crop. The paper analyzes the results of assessing the quality of the fruits of new and promising buckwheat varieties created by including fasciated forms in the composition of populations of materials of family-group selection. Promising genotypes have been identified for inclusion in the process of buckwheat breeding for high quality technological parameters and an increased amount of flavonoids in groats.

The research was carried out in order to evaluate new breeding material isolated from breeding nurseries of fasciated type. We studied 4 varieties of selection of Tatar Research Institute of Agricultural Sciences approved for cultivation and 4 hybrid populations that are in the selection study at the stage of competitive variety testing in the conditions of Pre-Kama region of the Republic of Tatarstan in 2018-2020. The work was carried out four times in the experimental field of Kazan State Agrarian University, the registered area of the plots was 10 m2. The soil of the experimental site is gray forest, medium loamy in granulometric composition, the content of humus according to Tyurin varied within 3.2– 4.4%. The growing seasons of the research years were characterized by instability of hydrothermal conditions. The vegetation of buckwheat in 2018 and 2021 took place in conditions of acute soil and atmospheric drought. The hydrothermal coefficient for Selyaninov during the growing season of buckwheat averaged 0.51 for the growing season of 2018, 0.29 for the growing season of 2021, indicating acute air and soil drought. In 2019, the average hydrothermal coefficient during the growing season was 1.05. The growing season of 2020 was quite humid. Throughout the entire period of growth and development of buckwheat plants, the amount of precipitation exceeded the average annual norms, while the temperature regime was at the level of the average annual data. The populations of K-850 (89.2%) and K-899 (89.7%) were the most environmentally sustainable on average. In the analysis of biological and grain productivity, populations of K-850 and K-900 were distinguished. The maximum grain size was obtained in the small-fruited Batyr variety - 582 g/l, the minimum grain size in the largest-fruited Chatyr Tau variety - 519 g/l. Increased ecological stability and relative stability of the crop under conditions of soil-atmospheric drought was revealed in populations K-850 and K-990. The size of the fruit is optimally combined with the reduced filminess of the K-850 and K-874 populations.