Validation of molecular genetic markers of the fertility restorer gene Rfo in rapeseed of VNIIMK breeding

The prospects of modern rapeseed breeding are aimed at the development of hybrids that can increase yield and oil yield by up to 50%. For the industrial production of hybrids, technologies are used that include lines with cytoplasmic male sterility (CMS) and lines with the fertility restorer gene (Rfo), which provide controlled hybridization. The use of Rfo gene markers can help reduce the time and cost of obtaining a hybrid. In this context, the validation of fertility restorer gene markers for introduction into breeding practice is relevant. For validation of Rfo gene markers, 4 pairs of primers and PGI-2 isoenzyme were tested on lines restoring rapeseed pollen fertility and lines with CMS, as well as 103 plants phenotyped for fertility-sterility trait based on the presence or absence of pollen during flowering. The optimal buffer system was selected for the separation of PGI-2 isoenzymes in a starch gel. The allele identified as Pgi-2 FF showed an association with the Rfo gene. However, visualization of the marker is difficult, labor intensive and expensive, making the use of a protein marker inefficient. Analysis of rapeseed lines using allele-specific primers revealed the association of three DNA markers with the pollen fertility restoration trait. Their validation on phenotyped rapeseed plants showed amplification of the expected marker fragments in Rfo gene plant carriers in an average of 96% of cases. Possible reasons for the discrepancy between the phenotypic manifestation of the trait and the allelic state of the marker are discussed. The selection process of Rfo gene carriers was optimized using real-time PCR.