A soybean germplasm collection was studied for the identification of accessions with low trypsin inhibitor content in seeds. Twenty-nine accessions, parental plants, and two hybrid populations were selected and analyzed using genetic markers for alleles of the Ti3 locus, encoding Kunitz trypsin inhibitor (KTI). Most of the accessions had high or very high KTI (49.22–73.53 Trypsin units inhibited (TUI/mg seeds), while the two local Kazakh cultivars, Lastochka and Ivushka, were found to have a moderately high content of KTI, at 54.16–54.87 TUI/mg. In contrast, two soybean cultivars from Italy, Hilario and Ascasubi, showed the lowest levels of trypsin units inhibited, at 25.47–27.87 TUI/mg. Electrophoresis of seed proteins in a non-denaturing system showed a simple discrimination pattern and very clear presence/absence of bands corresponding to KTI. The SSR marker Satt228 was the most effective diagnostic marker among the three examined, and it confirmed the presence of the homozygous null-allele ti3/ti3 in cultivars Ascasubi and Hilario, which were used for hybridization with the local cv. Lastochka. Heterozygote F1 hybrid plants and homozygous ti3/ti3 lines in F2 segregating populations were successfully identified using Satt228. Finally, through marker-assisted selection with Satt228, prospective homozygous ti3/ti3 lines were produced for further application in the breeding program aimed at improving soybean seed quality in Kazakhstan.
Pod dehiscence is one of the main factors which play a vital role on the final yield of many crops including soybean and, therefore, it is important to elucidate genetic mechanisms associated with this trait. In this study, morphological, physiological and biochemical analysis was conducted for pod and pod-related traits on 170 soybean genotypes with diverse origins. Subsequently, a genome-wide association study (GWAS) was performed using Silico-DArT and DArT SNPs markers. In total, 48 QTLs were identified with 14 stable QTLs, mostly located on chromosomes 6, 13 and 16, corresponding to pod dehiscence and pod-related traits. From putative candidate genes, two most stable and important genes for pod dehiscence with known functions were emphasised from the QTLs: Glyma.13G184500 and Glyma.16G141100, encoding transcription factors DNA-binding bromodomain-containing protein and C2H2 zinc finger protein, respectively. Finally, a genomic prediction approach was implemented to select genotypes most resistant to pod dehiscence. GWAS-derived markers confirmed the stable prediction of pod dehiscence in studied accessions from different populations and the best non-dehiscent soybean genotypes were successfully selected.
Yellow rust (Puccinia striiformis f. sp. tritici) is one of the most destructive diseases in wheat (Triticum aestivum L.) in Kazakhstan, causing significant yield losses. Owing to the high susceptibility of widely cultivated varieties, the development of resistant genotypes remains a key objective for sustainable crop protection. The aim of this study was to evaluate the resistance of wheat lines to yellow rust and to identify effective resistance genes. The research was conducted under artificial infection conditions using hybrid populations of the F2–F5 generations. The genotypes were assessed and ranked according to their resistance levels, and molecular markers were applied to detect resistance genes. Significant variability in disease response was observed. Analysis of variance revealed a strong effect of genotype on the infection coefficient (p < 0.001). Lines from later generations (F5) presented lower infection levels. Most genotypes carried the Yr5 gene, highlighting its major role in resistance, whereas Yr10 was less common. Yr15 and Yr18 were detected in some lines and were associated with partial (adult plant) resistance. Moderately susceptible forms predominated, indicating widespread quantitative resistance. However, highly resistant lines (CI = 0–1) and immune forms were identified, representing valuable material for breeding programs.