The possibility of using self-compatible forms of meadow clover (Trifolium pratense L.) in breeding to increase seed productivity

Abstract

A genetic source of self-compatibility was identified, sample No. 3000, whose offspring in the I1 generation had this property at the level from 18 to 100 %. The average seed setting rate for self-pollination was 77 %, which is many times higher than the self-compatibility rate for diploid varieties (0.5-1 %). Under mechanical action on inflorescences without tripping of flowers, the seed setting in the studied forms was 46 %. In reciprocal crosses with the Early 2 variety, a high heritability of the self-compatibility trait was found, which was observed in the F1 generation in 53 % of genotypes in direct and 74% in reverse crosses. Hybrid combinations of Early 2♀ x No.3000 I2♂ and No.226 BC ♀ x No.3000 I2 ♂ were created in generations I1 - I3, in the offspring of which an increase in the number of highly self-compatible genotypes was detected by 50% and 60%, respectively. By the I3 generation, self-compatible and weakly self-compatible genotypes were completely absent, and the percentage of medium-and high-self-compatible genotypes reached 100 %. Based on linear material (Early 2 x No. 3000 I2) I4, multilinear F1 populations were created and their seed productivity was evaluated. Self-compatible hybrids in the number of inflorescences exceeded the Early 2 variety by 19%; in seed setting-by 25-31 %, in seed weight from 1 plant-by 18-24 %. A breeding program was developed to create the source material of meadow clover (Trifolium pratense L.) with high seed productivity using a genetic source of self-compatibility.