Selection of vetch (Vicia sativa l.) genotypes resistant to abiotic environmental factors in the agrocoenoses with various supporting crops

Artificial selection of spring vetch began with hybrid materials selected from the nursery of the F1 hybrids. When studying spring vetch on different backgrounds, there was a significant difference between the offspring in terms of plant survival rate: against the background of oats, its values ranged from 21.8 to 34.4 % with an average of 27.5 %, and after white mustard - from 40 .2 to 53.35 % at - 47.2 %. Stabilization of the competitiveness of spring vetch in mixed sowing with oats was not observed, but there was a decrease in the share of full-fledged plants of the artificial population F4 from 0.5 to 7.9% compared to F3. There were more full-fledged spring vetch plants against the background of mustard, it was indicates that mustard has much lower competitiveness compared to oats. It was found that in each population plants with low productivity prevailed both after oats and after white mustard. The selection coefficient (per a sheaf) averaged from 19 % against background oats and up to 34.1 % - after white mustard, a total of 2240 elite plants were selected. Thus, at the first stage, spring vetch plants survived under cultivation with a supporting crop were selected. The survival rate of spring vetch in the agrocenosis with oats varied from 17.3 to 31.3 %. 2054 elite plants were obtained. The second stage of the artificial selection nursery was formed from the material of spring vetch which was tested for resistance to the competitive background of the previous year. The survival rate of spring vetch plants varied from 17.6 % to 24.5 %, 2432 elite plants were obtained. At the third stage, the offspring of spring vetch in mixed sowing with oat and white mustard was studied: 546 elite plants against the background of oat and 1694 against the background of white mustard were selected, with a total of 2240 elite plants selected. The percentage of selected plants indicates that spring vetch genotypes which cannot compete with the supporting crops and between themselves are eliminated from the population. Purposeful selection of artificial hybrid population of spring vetch promotes the formation of genetically balanced lines with increased resistance to abiotic environmental factors. Key words: spring vetch, hybrid, selection, productivity, mixed sowing.