2013 Annual Report
1a.Objectives (from AD-416):
Our objective is to develop landmark cultivars, advanced breeding lines and information for use by other breeders, scientists, producers and growers. This research will emphasize developing resistance to diseases, insects, and physiological defects, as well as the development of molecular markers for genetic analysis and marker assited selection.
1b.Approach (from AD-416):
Problems facing the lettuce industry will be addressed using genetic approaches in field, greenhouse, and laboratory experiments that are suited to coastal, desert, and interior valley locations, to the various types of lettuce, and to the demands of different production and marketing approaches.
The agreement was established in support of objective 1 of the parent project, the goal being to incorporate valuable traits into crisphead, mixed lettuce, and spring mix cultivars and breeding lines that are adapted to coastal California and low desert production conditions. In the 2012-2013 period, major efforts targeted resistance to lettuce big vein disease, lettuce drop caused by Sclerotinia species, Verticillium wilt, Fusarium wilt, lettuce powdery mildew, bacterial leaf spot, corky root, downy mildew, leafminer, lettuce aphid, tipburn, shelf-life of salad-cut lettuce, and multiple disease resistance. In all programs, horticultural traits, adaptation, and resistance to tipburn are essential. Selections were taken from breeding populations and advanced breeding lines were evaluated as part of breeding for resistance to big vein disease, downy mildew, lettuce drop, Verticillium wilt, Fusarium wilt, dieback, bacterial leaf spot, corky root, leafminer, tipburn, and pre-mature bolting. Genetic studies concurrent with breeding programs are being conducted to determine the inheritance of resistance to bacterial leaf spot, powdery mildew, leafminers, downy mildew, lettuce aphid, corky root, shelf-life of salad-cut lettuce, and Verticillium wilt.