Object: synthetic and analytical selection of radishes; source material for hybrid breeding. The aim: to determine the adaptive features of the formation of valuable economic traits of the radish gene pool and the creation of source material based on the improvement of methodological approaches for the selection of F1 hybrids. Methods: chemical mutagenesis - to obtain a new source of breeding material; visual - to account for and detect existing mutations, to establish the spectrum and frequency of mutations; field - laying of breeding nurseries, accounting for productivity and yield; determination of biological and morphological adaptive indicators of collection and selection samples; laboratory - to assess the sowing qualities of seeds, determine biochemical parameters; organoleptic - to assess the taste; statistical - processing of experimental data by methods of variation statistics. Novelty: For the first time in Ukraine, scientific problems have been solved to establish the laws of adaptive capacity and the relationship of valuable economic traits of the radish gene pool: identified sources of maturity, yield, productivity, chemical composition and resistance to abiotic factors. The adaptive ability and stability of the complex of selection traits of new radish lines created by the methods of induced mutagenesis, inbreeding and intraspecific hybridization were evaluated. Methodological approaches to expanding the spectrum of genotypic variability of radishes based on methods of chemical mutagenesis and synthetic selection have been improved; selection of genotypes valuable for selection on the basis of studying and identifying correlations between the manifestation of important quantitative traits, studies of the stability of their manifestation under different agroclimatic conditions of cultivation. Results: The genetic bank of sources on valuable economic signs is formed: manifestation of mutant genes in morphotype - 4, productivity - 7, productivity - 5, selection value of genotype on indicator "yield" - 4 and "duration of vegetation period" - 4, stability of manifestation of biochemical substances in the years of research - 6, their increased potential - 9. There are 6 self-incompatible lines with a set of valuable economic characteristics. Promising mutant lines of Duymovochka, Nastusya, Nika, Karamelka have been created and stable sources for the action of the mutagenic factor have been identified. Valuable radish lines have been created, which have replenished the gene pool of culture in Ukraine; lines are registered in the NCGRRU and are integral objects of the national scientific heritage of Ukraine. Degree of implementation: 2 methodical recommendations, introduced into the educational process of Kharkiv National Agrarian University named after V.V. Dokuchaeva, 76 valuable sources, 5 selection and valuable lines. The created source material is introduced into the selection programs of IOB NAAS, Institute of Horticulture NAAS, which is confirmed by the relevant acts
