Submitted to: Symposium Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 6/15/2007
Publication Date: 7/18/2007
Citation: Ramming, D.W. 2007. The USDA/ARS Grape Breeding Program at Parlier, CA. Proceedings. First Annual National Viticulture Research Conference, July 18-20, 2007, Davis, California. p. 73-74. Interpretive Summary: The grape industry needs a series of seedless grape cultivars that ripen from early to late in the season. The raisin industry needs seedless raisin cultivars that can be mechanically harvested without supplemental drying. Consumers are demanding fruit with less pesticide residues while growers need protection against plant diseases. The USDA/ARS at Parlier, CA has a grape breeding program to address the industry and consumer needs. Scarlet Royal provides a red seedless table grape that fills the production gap between Flame Seedless and Crimson Seedless Autumn King provides a very large white seedless table grape to extend the harvest season. Sweet Scarlet produces a red seedless table grape with exceptional eating quality and unique fruity Muscat flavor. Thomcord produces a seedless table grape for the farmers market with Concord flavor. DOVine and Selma Pete produce raisin grapes for mechanical harvest, saving growers labor and production costs. Summer Muscat and Diamond Muscat provide seedless Muscat flavored raisin grapes to replace the old seeded Muscat flavored variety, Muscat of Alexandria. Advanced table and raisin grape selections with resistance to powdery mildew and Pierce's disease and improved fruit quality have been developed. These selections provide breeding material to develop resistant varieties that will have lower pesticide levels.
Technical Abstract: The California table grape industry needs a series of seedless table grapes that ripen from early to late, having high quality red, black or white fruit that store and ship well. The raisin industry needs new seedless cultivars adapted to mechanical harvest without supplemental drying. Buyers and consumers are demanding more fruit with lower pesticide residues. New cultivars resistant to powdery mildew and Pierce’s disease are needed to help achieve this goal. The major objective of the USDA/ARS grape breeding program is the development of improved table and raisin grape cultivars including types resistant to powdery mildew and Pierce’s disease. Sweet Scarlet, a mid-season red seedless grape with a light fruity Muscat flavor; Scarlet Royal, a mid-season red seedless grape with neutral flavor; and Autumn King, a late season white seedless grape with neutral flavor have been released to the table grape industry. The raisin grapes, DOVine and Selma Pete, have been released for mechanical harvest after cutting canes while Summer Muscat and Diamond Muscat raisin grapes provide seedless Muscat flavored raisins. A Chinese source of PM resistance that segregates in a 1:1 ratio is completely resistant (no mycelium growth) or very susceptible with no intermediate types as found in other sources of resistance. Molecular markers were used to identify 20 PD resistant individuals in a BC2 family of 51 individuals from V. arizonica. After greenhouse tests, 12 were identified as highly resistant and this year they were backcrossed to high quality table and raisin grape selections to make a BC3 generation.