Uniformity and heterogeneity genotypes of winter wheat (Triticum aestivum L.) Varieties during basis seed production process

Abstract

Purpose and objectives. Improvement of the identification system of varieties to determine their heterogeneity in the primary seed production..

Materials and methods. Field studies, morphometrical analysis, electrophoresis of storage proteins, molecular-genetic analysis of alleles of microsatellite loci, mathematic and statistical methods.

Results and discussion. A system for the phased identification of winter bread wheat varieties using certain traits has been developed: at stage 1 the most informative and stable 8 morphometric and 16 qualitatively alternative characters are used; at stage 2 biochemical traits are used; at stage 3 molecular markers of the allelic state of microsatellite loci are used. According to this rating system, a scale is proposed for determining the heterogeneity of a variety in ascending order from 0 to 9 points. Specific examples of identification of varieties in the production primary of their seeds are considered. In 2006–2018 in the Department of Wheat Breeding and Seed Production PBGI - NCSCI, 86 winter bread wheat varieties bred in Ukraine and in other countries were studied using the comprehensive system for assessing the heterogeneity. They were rated according to the scale as follows: 12 varieties (14.0%) were completely uniform (0–1 points); 22 varieties (25.6%) - low heterogeneous (2-3 points); 36 varieties (41.8%) - medium heterogeneous (4-6 points); 16 varieties (18.6%) - highly heterogeneous. A significant portion of domestic varieties (48 varieties, 55.8%) were categorized as medium- or highly heterogeneous by biochemical and molecular markers. At the same time, these varieties can be considered visually uniform, since according to morphophysiological characteristics they correspond to the DUS-test requirements. The vast majority of these varieties are characterized by increased adaptability (frost tolerance, drought resistance) and grain quality indicators typical for strong and valuable wheats. It was shown that, depending on breeding methods and designs, a certain level of heterogeneity is intrinsic to "young", newly developed varieties.

Conclusions. The developed comprehensive system for the phased identification of winter bread wheat varieties and the determination of their heterogeneity is the most expedient to use in the primary (pre-basic) seed production.