DNA marker identification of downy mildew resistance locus Rpv10 in grapevine genotypes

Area of Science:

• Plant Pathology
• Molecular Genetics
• Viticulture

Background:

• Downy mildew (Plasmopara viticola) is a major threat to Vitis vinifera grapevines, which lack natural resistance.
• Resistant grape varieties often originate from North American and Asian species, necessitating interspecific crossing for breeding.
• Molecular genetic methods, including DNA markers, are crucial for efficient breeding of resistant cultivars.

Purpose of the Study:

• To identify grapevine genotypes carrying the downy mildew resistance locus Rpv10.
• To investigate the presence of Rpv10 in 30 candidate grape cultivars using molecular markers.
• To clarify the parentage and resistance gene donor of the grapevine cultivar Korinka russkaya.

Main Methods:

• Polymerase Chain Reaction (PCR) analysis was employed to screen 30 grape cultivars for the Rpv10 locus.
• High-precision data acquisition was performed using an automatic genetic analyzer.
• Microsatellite (SSR) loci fingerprinting and VIVC database analysis were used for cultivar identification and pedigree verification.

Main Results:

• The Rpv10 resistance allele was detected in 10 out of 30 screened grapevine genotypes.
• DNA marker analysis initially suggested the presence of Rpv10 in Korinka russkaya, contradicting its known pedigree.
• Further analysis confirmed Severnyi as the true donor of the Rpv10 locus to Korinka russkaya, correcting its established parentage.

Conclusions:

• The study successfully identified new potential donors for downy mildew resistance in grapevines.
• Molecular marker analysis is effective in detecting resistance loci and verifying grapevine pedigrees.
• The research clarified the genetic background of Korinka russkaya, confirming its inheritance of the Rpv10 resistance locus.