Genetic modification of European winegrapes with genes from an American wild relative confers resistance to the major diseases powdery and downy mildew

Authors: FEECHAN, ANGELA - Commonwealth Scientific And Industrial Research Organisation (CSIRO); ANDERSON, CLAIRE - Commonwealth Scientific And Industrial Research Organisation (CSIRO); TORREGROSA, LAURENT - Institut National De La Recherche Agronomique (INRA); JERMAKOW, ANGELICA - Commonwealth Scientific And Industrial Research Organisation (CSIRO); MESTRE, PERE - Institut National De La Recherche Agronomique (INRA); WIEDEMANN-MERDINOGLU, SABINE - Institut National De La Recherche Agronomique (INRA); MERDINOGLU, DIDIER - Institut National De La Recherche Agronomique (INRA); WALKER, AMANDA - Commonwealth Scientific And Industrial Research Organisation (CSIRO); Cadle-Davidson, Lance; REISCH, BRUCE - Cornell University; AUBOURG, SEBASTIEN - Institut National De La Recherche Agronomique (INRA); BENTAHAR, NADIA - Institut National De La Recherche Agronomique (INRA); SHRESTHA, BIPNA - Institut National De La Recherche Agronomique (INRA); BOUQUET, ALAIN - Institut National De La Recherche Agronomique (INRA); ADAM-BLONDON, ANNE-FRANCOISE - Institut National De La Recherche Agronomique (INRA); THOMAS, MARK - Commonwealth Scientific And Industrial Research Organisation (CSIRO); DRY, IAN - Commonwealth Scientific And Industrial Research Organisation (CSIRO)

Submitted to: Plant Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/2/2013
Publication Date: 10/17/2013
Citation: Feechan, A., Anderson, C., Torregrosa, L., Jermakow, A., Mestre, P., Wiedemann-Merdinoglu, S., Merdinoglu, D., Walker, A., Cadle Davidson, L.E., Reisch, B., Aubourg, S., Bentahar, N., Shrestha, B., Bouquet, A., Adam-Blondon, A., Thomas, M., Dry, I. 2013. Genetic modification of European winegrapes with genes from an American wild relative confers resistance to the major diseases powdery and downy mildew. Plant Journal. 76, 661-674.

Interpretive Summary: The two most economically important diseases of grapevine cultivation worldwide are powdery mildew and downy mildew. These pathogens are from North America, were introduced into Europe in the 1800s, and have subsequently spread to all major grape producing regions of the world. Grape growers continue to plant traditional susceptible varieties and now rely heavily on the use of agrochemicals to minimize the potentially devastating impact of these pathogens on grape yield and quality. Wild North American muscadine grapevines coevolved with powdery and downy mildew and were recognized as early as 1889 to be resistant to both pathogens. Continuing a genetic study initiated in 1919, we identified two closely related genes at a single location in the muscadine grape genome. Following genetic transformation into susceptible V. vinifera winegrape cultivars, these genes provide strong resistance against powdery and downy mildew. This knowledge supports the development of reduced-spray varieties using either traditional breeding or transgenic approaches, providing a new solution for disease control without the intensive application of agrochemicals.

Technical Abstract: The two most economically important diseases of grapevine cultivation worldwide are caused by the fungal pathogen powdery mildew (Erysiphe necator syn. Uncinula necator) and the oomycete, downy mildew (Plasmopara viticola). These pathogens, endemic to North America, were introduced into Europe in the 1800s and have subsequently spread to all major grape producing regions of the world1, 2. Grape growers continue to plant traditional susceptible varieties and now rely heavily on the use of agrochemicals to minimize the potentially devastating impact of these pathogens on grape yield and quality. The wild North American grapevine species Muscadinia rotundifolia coevolved with powdery and downy mildew and was recognized as early as 1889 to be resistant to both pathogens3. Continuing a genetic study initiated in 1919, we now demonstrate that two closely related genes designated resistance to Uncinula necator (RUN1) and resistance to Plasmopara viticola (RPV1) from a single M. rotundifolia locus, confer strong resistance to these pathogens following genetic transformation into susceptible V. vinifera winegrape cultivars. The generation of premium winegrape cultivars with powdery and downy mildew resistance provides the global winegrape industry with a genetic modification solution for disease control without the intensive application of agrochemicals.