Genotyping with SSR markers and assessment of the genetic polymorphism in beet (Beta vulgaris L.) accessions from the VIR collection
Abstract
Background. Microsatellite markers (SSR) continue to be the most effective way to study the genetic diversity in crop genebanks, including beet ( Beta vulgaris L.) germplasm. They are also used for identifying individual genotypes. The worldwide diversity of beet is preserved in the VIR genebank, which has a history of over a hundred years and incorporates 2,422 accessions from all over the world. Because of the multitude of accessions in the collection, a significant number of them have not yet been analyzed with SSR markers. Thus, there is an opportunity for their genetic characterization at a deeper level. Materials and methods. A set of 35 transcriptome-derived SSR markers were employed to analyze 96 randomly selected beet accessions, grouped according to their specific traits. Fragment analysis was performed with a NANOFOR 05 genetic analyzer, and the data were processed using the Peak Scanner, Excel, GenAlEx, PHYLIP, and Unipro UGENE software packages. Results. As a result, 293 alleles in total were found in 35 loci, with allele numbers varying from 4 to 13 per locus. The observed heterozygosity ( He ) level was quite high, about 0.75, thus indicating a high level of genetic variability. It turned out that there were 50 unique alleles for table beet identification, 28 for fodder beet, and 9 for sugar beet. These figures revealed a divergence in diversity levels of these groups. The study provided further confirmation of the high polymorphism in beet germplasm accessions. Conclusion. The data obtained summarily demonstrate the capacity of the selected marker set to characterize genetic variation in VIR’s beet collection, provide more knowledge about the origin of the accessions, and ensure their correct genotyping. Furthermore, the set can serve as an effective tool for genetic certification and management of beet germplasm, thus contributing to future breeding and conservation efforts.