Associations between allelic differences of the fifth group chromosome loci and a complex of agronomically valuable traits in common wheat (Triticum aestivum L.)

Aim. Characterization of recombinant inbred wheat lines by agronomically relevant traits and detection of asso- ciations between their expression level and allelic differences of microsatellite loci of the fifth group chromosomes. Methods. Phenological observations, morphometric indicators, and elements of crop structure. Statistical analysis of the obtained data was carried out in Microsoft Excel. The significance of the difference between samples was assessed by Fisher’s F test. A difference of p < 0.05 was considered statistically significant for all indicators. Results. The poly- morphism of the parental genotypes and the population of 47 recombinant-inbred lines (RILs) F7 from the crossing of the winter wheat varieties Luzanivka odeska and Odeska chervonokolosa over three years (2016–2018) in conditions of the Southern Steppe (Odesa) was evaluated according to eight characteristics: duration of a period prior to heading, plant height, productive tillering, grain number per spike, grain weight per spike, thousand-grain weight, productive tiller number per unit area and grain yield. The comparison of the data of line evaluation by agronomic traits against the data of microsatellite analysis of lines by 14 microsatellite loci of the fifth group chromosomes demonstrated the associations between several loci and grain yield and between two loci and plant height. Conclusions. The changes in grain yield in the most unfavorable year, 2018, were associated with allelic differences of lines at locus Xbarc319- 5A, and in the most favorable year, 2017, – with another locus of chromosome 5A, Xbarc330-5A. In both cases, the lines that had an allele from Odeska chervonokolosa were characterized by a significantly higher level of grain yield compared to the lines that had an allele from the Luzanivka odeska variety. There are at least two QTLs on 5B chromo- some, associated with winter wheat grain yield in favorable growing years. The first of them is located in the region of locus Xbarc88-5B, and the second – in the region of loci Xwmc415-5B, Xgpw3191-5B, and Xcfd7-5B. Based on the alleles of the specified microsatellite loci, which are linked QTLs of grain yield, it is possible to select genotypes at the early stages of selection that will give a higher yield in years with favorable conditions for growing wheat.