Variability of the effects of combining ability in the breeding of F1 radish hybrids

Abstract

Based on homozygous lines, three sterile and seven fertile, radishes were crossed by the method of two groups of genotypes. The resulting offspring and parental lines were tested when growing in soil, in a film greenhouse, using traditional techniques. The experiment was repeated twice to identify hybrid combinations showing consistent performance. The grown plants were evaluated according to economically valuable traits: the weight of the root crop and the aboveground vegetative part, the length, and diameter of the root crop. In the method proposed by V.K. Savchenko, statistical indicators of the combining ability of lines were calculated, including the effects of GCA. When tested at different times, we identified lines that changed the direction of the action of genes on the manifestation of quantitative traits. For the selection of lines for future breeding programs, lines were selected that showed stable performance. The test took the indicators of the inbred lines themselves, which made it possible to assess the relationship of the phenotypic manifestation of the trait with the effects of GCA of the same lines. The presence of close relationships allows simplifying the work of breeders, namely, to assess the manifestation of a trait in plants, without evaluating the offspring. For the same purpose, the presence of relationships between quantitative signs was assessed; during the test, close correlations were found in the first period, while in the second period they were absent. The data obtained indicate the unreliability of even close correlations obtained from the results of single tests. The indicators of the GCA effects of the studied lines are applicable for the selection of only a specific breeding institution, while the comparison of indicators for two or more test periods helps to identify patterns in the control of the inheritance of the studied quantitative traits.