Plant & Animal Genome VI Conference Plant & Animal Genome VI Conference
P77
USDA-ARS, U.S. Water Conservation Laboratory, New-Crops Group, 4331 East Broadway Rd., Phoenix AZ 85040
Lesquerella fendleri (Brassicaceae), is a native plant to southwestern US, and a new industrial crop which has evoked interest for it's unique oil and hydroxy fatty acid (lesquerolic acid). The difficulty to isolate DNA due to high polysaccharide content in L. fendleri tissue, was an impediment for applying molecular breeding methods to its domestication and improvement. We are describing here a novel DNA isolation method for this plant. In this procedure, after breaking down the cell walls, the cell nuclei were separated from the cytoplasmatic and intracellular fluids by differential centrifugation in a viscous medium, this preparatory step separates the cellular compartments which contain the desired DNA and the problematic carbohydrates. The DNA is then isolated from the nuclei without interference. High quality DNA was obtained, and used successfully in a male-sterility study using Random Amplified Polymorphic DNA (RAPD), to identify markers that are associated with this trait. A sample of
20 plants, composed of ten male sterile plants, and 10 male fertile plants were used for the initial screening. After screening 50 primers, we identified OPL-02, OPL-04, OPL-19, OPZ-11, OPZ-14 as primers that amplify DNA segments potentially diagnostic for fertile or sterile male genotypes. Using the RAPD data we have estimated L. fendleri genome size to be 1.7x 109. Eighty six percent of the RAPD were polymorphic, which indicates high genetic variability within L. fendleri.