DNA marker identification of Rpv3 downy mildew resistance gene in seedless grape varieties

Abstract

Table grapes are a valuable dietary product. Seedless grapes are in high demand among consumers. For this reason, the breeding of seedless varieties is one of the popular trends in modern viticulture, along with the production of environmentally friendly products. Downy mildew (Plasmopara viticola (Berk. & M.A. Curtis) Berl. & De Toni) is one of the most common fungal diseases of the grapevine. Most downy mildew resistant grape accessions belong to North American species like Vitis aestivalis Michx., V. berlandieri Planch., V. cinerea (Engelm. ex A. Gray) Engelm. ex Millard, V. riparia Michx., V. rupestris  Scheele, etc. The search for donors of resistance genes is an urgent task. Rpv3 is one of the most significant resistance genes from a number of North American grape varieties. The aim of this work is to identify the downy mildew resistance gene Rpv3 in seedless grape varieties by means of DNA-marker analysis. The grape varieties with rudimentary development of seed in berries and with North American species in the pedigree were chosen as the object of the study. The varieties “Dunavski lazur” and “Seyve Villard 12-375” with reference alleles were used as the positive control, while V. vinifera L. was used as the negative control. UDV305 and UDV737 DNA-markers were used in this study to identify the allelic type of the Rpv3 gene. The work was performed using the polymerase chain reaction. The reaction products were separated by capillary electrophoresis using the ABI Prism 3130 automatic genetic analyzer. Evaluation of the results was done using the GeneMapper and PeakScanner software. Functional alleles of the downy mildew resistance gene Rpv3 were revealed in grape  varieties “Kishmish zaporozhskiy”, “Lady Patricia”, “Remaily seedless”, “Pamyati Smirnova” and “Shayan”. Rpv3299-279, one of the seven known haplotypes, was identified in all the varieties. The pedigree analysis of the studied varieties indicated that the parental forms – “Seyve Villard” and “Seibel” hybrids – are presumably the donors of the gene. Grape accessions with the identified Rpv3 gene can be used in seedless varieties breeding as donors of resistance to downy mildew.