Identification of an NBS-LRR gene conferring total resistance to grapevine downy mildew

Viticulture is an important component of the French economy. Downy mildew of grapevine is one of the most damaging diseases for viticulture. Resistant varieties represent the most credible alternative to the use of pesticides to combat downy mildew. Because grapevine cultivated in Europe (Vitis vinifera) is susceptible, resistance must be introduced from other Vitis species. The Rpv2 gene, originating from Vitis rotundifolia, confers complete resistance to grapevine downy mildew. Using genetic mapping, sequencing of recombinant individuals, in silico chromosome painting, and comparative genomics within the Vitaceae family, Rpv2 has been restricted to a 250 kb genomic region containing two NBS-LRR resistance genes. This work also shows that Rpv2-mediated resistance leads to the restriction of pathogen growth early in the infection cycle. These results help to understand the benefits and risks associated with the use of Rpv2 in breeding programs.

Publication: Theoretical and Applied Genetics doi.org/10.1007/s00122-025-04959-z
Contacts: Pere Mestre, Camille Rustenholz