The object of the study: to analyze the characteristics of the changes in traits depending on mutant generations of amaranth varieties under the action of various gamma-radiation doses in order to isolate mutant lines with economically valuable traits that can be used as starting material in the selection process. The objective of the study: determination of the varietal specificity of amaranth and the variability of its quantitative traits after exposing the culture seeds under the action of various doses of gamma-radiation; isolation of the mutant lines with economically valuable traits that can be used as starting material in the selection process. Research methods: general scientific, field, laboratory, special-selection, biochemical, statistical. Novelty: The effectiveness of the radiation mutagenesis was studied in Ukraine for the first time to obtain selectively valuable amaranth lines of the species A. hуpochondriacus L. The optimal doses of gamma-radiation for this culture and the laws of their genetic effects were determined, the existing method of preparing temporary preparations was improved, the nature of the variability of the signs and their inheritance in the M2 and M3 lines, isolated mutant lines with marker signs. The increase in mitotic activity in meristematic cells of amaranth varieties Student`s, Kharkiv-1 and Sam of gamma-radiation of seeds with a 15 Gy dose and processing of the amaranth seeds with 150 Gy, 400 Gy and 700 Gy doses negatively influenced on the process of cell division, and led to the complete suppression of mitotic activity. The increase in the frequency of chromosomal abnormalities in meristematic cells was observed with increasing the dose of gamma-radiation. The varietal specificity of the white seed amaranth (A. hуpochondriacus L.), which is manifested in increased induced mutability of the Student`s variety compared to the varieties Kharkiv-1 and Sam, has been proven. The morphological mutants with a high content of protein, oil and with modified fatty acid composition had been obtained. The existing method of obtaining temporary preparations for examining the phases of mitosis has been improved, which increases the effectiveness of studying the effect of various gamma-radiation doses on the frequency of mitotic disorders of the root meristem cells of various cultivars. The establishment of the efficiency of inducing new mutant signs of amaranth in the M1, M2 and M3 lines, which can be used as a marker for the creation of new varieties in this culture, was further developed. Results: The optimal 150 Gy dose has been determined, which ensures the production of mutant lines, among which are the mutants with a high content of protein, oil and its modified fatty acid composition. 4 mutant lines were selected and they were transferred for the usage in the selection process to the National Center for the Plant Genetic Resources of Ukraine. “The Method for determining mitotic disorders in the amaranth root meristem for the usage in mutational breeding” has been developed. In the Student`s variety was obtained the mutation called early ripeness under the influence of the 15 Gy dose (-10 days before control). The extent of adoption: The results of the study are summarized in the monograph “Amaranth: breeding, genetics and growing prospects” and now used in the teaching method complex for the discipline “Special selection of the field crops” and “Genetics” of the V.V. Dokuchaev KNAU. The scope of implementation: Scientific institutions of the National Academy of Agrarian Sciences, the National Academy of Sciences and the Ministry of Agrarian Policy of Ukraine, educational institutions, agroformations of the AIC of Ukraine.
