Plant & Animal Genomes XI Conference

January 11-15, 2003
Town & Country Convention Center
San Diego, CA

Workshop: Citrus
            

A FUNCTIONAL GENOMICS APPROACH TO ENHANCED CITRUS, PRODUCTIVITY DISEASE RESISTANCE AND FRUIT QUALITY

¹ Department of Pomology, University of California, 1 Shields Ave, Davis, CA 95616, USA

² Department of Plant Pathology, University of California, 1 Shields Ave, Davis, CA 95616, USA

³ Department of Entomology, University of California, 1 Shields Ave, Davis, CA 95616, USA

⁴ Department of Plant Pathology, University of California, Riverside, CA 92521, USA

The focus of effort in Northern California is the discovery and identification of citrus fruit-specific genes that determine quality and the use of transgenic approaches to make citrus crops more productive. Enhancing fruit quality is key to marketing fresh citrus fruits as it greatly affects consumer preferences. These preferences, in turn, impact the livelihood of citrus growers throughout the United States, and indirectly the nutritional quality of American diets. The primary aim of the gene discovery effort is to sample the transcriptomes and proteomes of developing citrus fruit with particular emphasis on identifying transcripts and proteins that are associated with various fruit quality attributes including color, juice content, flavor, sugar-acid ratio, nutrition, nutriceuticals, as well as disorders that affect the juice sacs and peel components of citrus fruit such as granulation and crease, respectively. A necessary component of the gene discovery program is development of highly efficient plant transformation tools to validate novel fruit specific genes and to enable the functional analyses of key metabolic pathways. Novel approaches are being investigated to improve regeneration and transformation of citrus tissues. In the area of productivity, the focus is on developing resistance to citrus tristeza virus (CTV) and the analysis of genes that modify plant architecture and growth habit. For resistance to CTV, the emphasis is to use highly efficient gene silencing methods to target selective regions of the CTV genome that will provide resistance to the greatest number of CTV isolates as well as to inhibit aphid transmission and the viral suppression of gene silencing.