Inheritance of the trait «number of bolls on a plant» in intra-species and inter-species hybrids of oil flax

Abstract

To accelerate the production of oil flax forms with improved indicators, it is necessary to know the nature of the genetic interaction in hybrid populations, in particular, the heritability of quantitative traits of seed productivity. Effective selection of plants is possible with a simultaneous combination of two conditions: wide phenotypic variability of the population and high heritability of the trait. For selection, genotypic variability is important, which is determined using the coefficient of heritability (H). The use of this genetic-statistical parameter makes it possible to speed up and optimize the breeding process by selecting genotypes with a new, more favorable combination of valuable traits and rejecting low-value material at the first stages of breeding. The aim of the study is to identify interspecific and intraspecific hybrid combinations with high rates of heritability, promising for the selection of plants with a large number of bolls. The research was carried out at the Institute of Oilseed Crops NAAS in 2019-2020. The material of the study was interspecies and intraspecies hybrids of oilseed flax of the second generation obtained in the system of dialle crosses of three samples of cultivated flax (L5, L6, M32/2) and two wild species (L. angustifolium, L. hispanicum). The second generation hybrids were studied in the F2 hybrid nursery in blocks according to the scheme: maternal form – forward and reverse F2 hybrid – parental form. Boll structure analysis was performed on 150 F2 hybrid plants and 20 parental plants. The coefficient of heritability (H) was determined by the formula (Ayala 1984) and subdivided according to the gradation (Ala 1976) into: high – 0,66-1,0; medium – 0,33-0,65; low – 0,00-0,32. As a result of researches it is established that at interspecies and intraspecies hybrids of the second generation the sign «number of bolls on the plant» was inherited in average and high degree (H = 0,48-0,90, 0,52-0,87 accordingly). Highlighted promising hybrid combinations with a high heritability of the number of bolls, which can be used to predict the efficiency of plant selection in early generations (F2-F3). The most valuable for selection are hybrid combinations, in which high rates of heritability rates are noted for two years of research: interspecific L. angustifolium × M32/2 – 0,79-0,83, M32/2 × L. angustifolium – 0,76-0,80, M32/2 × L. hispanicum – 0,82-0,90; intraspecific L5 × M32/2 – 0,71-0,81, M32/2 × L6 – 0,80-0,87.