The thesis is devoted to the investigation of gene polymorphism in soft wheat varieties using molecular markers. The features of the allelic composition of the loci of high molecular weight and low molecular weight glutenins, microsatellite loci in a varieties of common wheat of Ukrainian selection are determined. The allelic composition of Rht8, Vp-1B, Lr34/Yr18 /Pm38 genes were established. The Rht8 gene is associated with plant height, the Vp-B1 gene is concerned with pre-harvest wheat grain germination, the Lr34/Yr18 /Pm38 gene has resistance against brown and yellow rust and powdery mildew diseases.
The allelic composition of the Glu-B1, Glu-B3, and Glu-A3 loci was determined. Four alleles were detected at the Glu-B3 locus: Glu-B3b, Glu-B3j, Glu-B3g, Glu-B3d. Two alleles were detected at the Glu-A3 locus. At the Glu-B1 locus, 4 alleles were detected. To determine the connection of the wheat baking quality with allelic composition of the Glu-B1, Glu-A3, Glu-B3 loci, we estimated the sedimentation index, flour strength, and dough elasticity index. The dependence of the technological parameters of the studied wheat varieties on the allelic state of the Glu-B1 locus was shown. In the samples with the Glu-B1al allele, the highest sedimentation rate was observed; the samples with the Glu-B1d allele were characterized by the lowest sedimentation rate. It was shown that in the samples with the Glu-B1al allele, the flour strength was the highest, while the samples with the Glu-B1d allele those parameters was the lowest. It was found that wheat varieties with the Glu-B1al allele demonsrated the level highest of “test elasticity index” (about 70%), in samples with the Glu-B1d allele this indicator was lower (about 51%).
During studying the effect of the Glu-B3 locus alleles on the sedimentation index, it was found that the highest sedimentation index is characteristic of samples with the Glu-B3g allele. Samples that had the Glu-B3j allele showed the lowest sedimentation rate. A high rate of flour strength, equal to 406,0 a.u., was characterized by samples that had the Glu-B3g allele. In samples that had the Glu-B3d allele, the lowest flour strength indicator was set at 215,0 a.u. Then, as in the samples with the Glu-B3b allele, the "test elasticity index" was the highest – 68,5%. In the samples that had the Glu-B3j allele, the indicator “test elasticity index” – 52,0% was the smallest. When analyzing wheat samples at the Glu-A3 locus, it was shown that samples with the Glu-A3c allele are superior to wheat samples with the Glu-A3d allele in all three indicators: sedimentation rate, flour strength, elasticity index.
The allelic composition of the Vp-1B gene in Ukrainian wheat was determined. The connection of the alleles of the Vp-1B gene with resistance to preharvest seed germination in analyzed varieties of red grain wheat was shown. It was established that the studied samples of Ukrainian wheat have three alleles of the Vp-1B gene. The Vp-1Bc allele is found with the greatest frequency. It was shown that in samples that are resistant to preharvest germination, the Vp-1Bc allele predominates, and for no-resistante ones, Vp-1Ba.
