FIELD EVALUATION OF HLB THERAPEUTICS

Both greenhouse and field plot experiments will be performed. Experiments will include delivery of therapeutic molecules to the citrus trees following any of three different application approaches: 1) testing of transgenic plants engineered to induce resistance/tolerance into the citrus; 2) Direct plant infusion where therapeutic molecules are applied directly to the plant using various infusion methods being developed; and 3) Symbiont attachment, where citrus cells are modified to exist as symbionts on a tree and produce molecules that move systemic in the tree to induce HLB resistance/tolerance. As part of the symbiont protocol, application methods developed by USDA will be tested in both greenhouse and field conditions. Performance of plants will be evaluated by monitoring: trunk diameter, tree canopy health, disease symptoms, fruit yield, fruit drop, plant nutritional status, root growth and titer of bacteria that causes HLB disease. Greenhouse and field experiments will be performed in the USDA, USHRL greenhouse facilities and at the Picos farm research plots. Further experiments may be established and evaluated at other sites in Florida.