This award will support cooperative research between Dr. Ronald H. Brlansky of the University of Florida and Dr. Helen Garnett of the University of Wollongong. This research is to evaluate mild citrus tristeza virus (CTV) from both Florida and Australia under uniform environmental conditions for protecting ability against severe stem pitting Australian and quick decline Florida strains of viruses. Methods will be developed to differentiate mild and severe CTV strains from both countries by screening libraries of cDNA clones for different hybridization, enumeration and charac- terization of the intracellular bodies characteristic of virus diseases, and development of monoclonal antibody protection against these infections. The project represents excellent U.S.-Australian collaboration in offering the opportunity to compare and evaluate CTV strains from both Australia and Florida for their virus-protecting abilities. This is important fundamental work using advanced DNA-related techniques to develop reliable chromosome markers of plant viruses, as well as having potential for eliminating major virus- disease threats to citrus production worldwide.
