Winter wheat (triticum aestivum l.) mutation depression under gamma-rays action

The purpose of our investigation was to identify the features of the depressive effects of the aftereffect of different doses of gamma-rays on winter wheat varieties of local breeding in terms of germination, survival, morphometry, yield. The parameters of germination and survival, the passage of the main phases of ontogenesis in winter wheat plants of French varieties (Courtiot and Gallixe) at the first generation were studied. The influence of mutagenic depression on parameters of yield structure (morphometry of mature plants) was established and the level of their variability was estimated too. In 2019 - 2020, experiments were conducted in the research fields of the research center of the Dnieper State Agrarian and Economic University. The experiments used seeds of Courtiot and Gallixe varieties, irradiated with gamma rays in doses of 100, 150, 200, 250, 300 Gy. Control was dry seeds. The variety Gallixe can be classified as resistant to gamma-rays, the variety Courtiotwas corresponded to high-sensitive. Parameter of germination and survival were directly correlated with increasing dose, with a dose of 200 Gy already semi-lethal, a dose of 250 Gy for variety Courtiot was sublethal, 300 Gy doze full-lethal, for the variety Gallixe sublethal was 300 Gy dose by which almost no plant material was obtained. Such parameters as plant height, weight of grain from the main spike and weight of thousand grains, partially (except for doses of 100-150 Gy) weight of grain from the plant reliably reproduce the mutagenic depression. Depression of the variety is affected by the dose of mutagen more than the genotype of the variety; the plant height parameter clearly demonstrates mutagenic depression. According to the results of factor and discriminant analysis as indicators affected by genotype-mutagenic interaction should be used germination and survival, pollen sterility, plant height, grain weight per spike, weight of thousand grains. Doses of 100 - 200 Gy are optimal for further use to obtain mutations; it is possible to use a dose of 250 Gy for the variety Gallixe.