The presence of awns on the ear is associated with a number of important plant properties, such as drought resistance, quality of the grain mass during processing, etc. The main manifestations of this trait are controlled by the B1 gene, which has recently been identified and encodes the C2H2 zinc finger transcription factor. Based on the previously identified SNPs in the promoter region of this gene, we constructed markers for dominant and recessive alleles which determine awnless and awned phenotypes, respectively. The markers were successful for use in targeting the respective alleles of the B1 gene in 176 varieties of common wheat, accessions of T. spelta L., as well as on F2/F3 hybrids from crosses between awned and awnless forms of T. aestivum. We first identified a new allele, b1mite, which has both an insert of a miniature Stowaway-like transposon, 261 bp in length, and 33 novel SNPs in the promoter region. Despite these changes, this allele had no effect on the awned phenotype. The possible mechanisms of the influence of the analyzed gene on phenotype are discussed.

Increasing the shelf life of potato tubers demands their storage under low temperature. However, storage at low temperatures causes activation of cold-protective mechanism, so-called cold-induced sweetening (CIS). During this process, the starch is converted into reducing sugars such as glucose and fructose. Upon processing at high-temperature, these sugars react with free amino acids, resulting in brown, bitter-tasting products, which reduces the consumer value of potatoes. In this study, we performed expression analysis of genes associated with cold-induced sweetening in potato tubers: vacuolar invertase (Pain-1), sucrose-synthase (SUS4), invertase inhibitor (InvInh2). Potato varieties Nikulinsky, Symphony, Nevski were used. All three varieties were found to accumulate sugars at low temperatures, the maximum accumulation of reducing sugars being observed at 4°C. It was found that the expression pattern of genes associated with cold-induced sweetening differs depending on the variety and storage duration. The increased expression of vacuolar invertase and its inhibitor is more pronounced at the beginning of storage period while the increased expression of sucrose synthase is more pronounced after three months of storage. At early storage periods, high expression of invertase and low expression of inhibitor is observed in Dutch variety Symphony, and vice versa in Russian varieties Nikulinsky and Nevsky. The participation of the studied genes in the process of cold-induced sweetening is discussed.

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