Location: Crop Improvement and Protection Research2009 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. Documents Trust with CALIFORNIA LEAFY GREENS RESEARCH BOARD. Log 38368.
3. Progress Report
Our objectives are to incorporate resistance to several diseases, insects, and physiological defects into iceberg, romaine, and mixed lettuce cultivars and breeding lines adapted for coastal and desert production. In 2009, major efforts targeted resistance to lettuce big vein disease, lettuce drop / Sclerotinia species, Verticillium wilt, Fusarium root rot, lettuce dieback/tombusviruses, bacterial leaf spot, corky root, leafminer, lettuce aphid, tipburn and multiple disease resistance. Minor programs addressed resistance to powdery mildew and yellow spot. In all programs, horticultural traits, adaptation, and resistance to tipburn are essential. In 2009, we confirmed resistance in previously identified germplasm, and new candidate sources of resistance were identified. Selections were taken from breeding populations and advanced breeding lines were evaluated in field and greenhouse experiments. Genetic studies concurrent with breeding programs are being conducted to determine the inheritance of resistance to big vein disease, bacterial leaf spot, dieback, lettuce mosaic virus, leafminers, downy mildew, lettuce aphid, corky root, and Verticillium wilt. These accomplishments aligns with National Program 301 component 3, and address problem statement 3C.