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ARS Home » Pacific West Area » Parlier, California » San Joaquin Valley Agricultural Sciences Center » Crop Diseases, Pests and Genetics Research » Research » Research Project #436612

Research Project: Breeding and Evaluation of Seedless Table Grapes with Superior Quality Including Types Resistant to Powdery Mildew

Location: Crop Diseases, Pests and Genetics Research

Project Number: 2034-21220-007-026-T
Project Type: Trust Fund Cooperative Agreement

Start Date: May 1, 2019
End Date: Mar 31, 2022

1. Develop seedless table grapes ripening throughout the maturity season, having white, red and black fruit, and fruit quality characteristics exceeding those of existing cultivars. Emphasis will be placed on developing new white and red seedless grapes that ripen during the early season. 2. Develop seedless table grapes with durable powdery mildew resistance and commercial fruit quality. 3. Produce, package and store for evaluation, advanced table grape selections from breeding program and competing cultivars. Provide fruit quality results for applied cultural treatments to assist in grower evaluations of advanced selections at California Table Grape Commission Research Committee meetings scheduled during the growing season. 4. Develop genetic markers associated with flowering time, veraison time, and time to full color in table grape.

Standard breeding methods are being used in this breeding program. Methods involve selecting accessions having the most desirable combination of characters, hybridizing those accessions, and selecting the most elite offspring and testing them as potential varieties. Breeding efficiency is enhanced through the standard use of embryo culture to produce progenies from seedless x seedless crosses. Advanced selections are tested in demonstration plots to determine commercial potential relative to competing cultivars. Powdery mildew resistance will be incorporated into high quality table grape germplasm through direct hybridization. Selection for powdery mildew resistance in appropriate progenies will initially occur in the greenhouse at the seedling stage. Powdery mildew resistant seedlings will then be transplanted to field sites where fungicides are not used for further evaluation.