Project Number: 6618-22000-034-10
Project Type: Specific Cooperative Agreement

Start Date: Aug 24, 2005
End Date: Aug 24, 2010

Objective:
Determine genetic, epidemiological, biochemical, biological, and serological characteristics of Citrus Tristeza Virus and of the exotic pathogens to improve citrus productivity and to support regulatory actions. Determine nature of host-pathogen interactions, especially as related to host resistance. The following objectives are being proposed for the FY08 funding cycle: This project is to provide a technology and a service that will complement laboratories involved in development of methods to control the citrus canker and HLB bacteria, and development of citrus trees resistant to these diseases. We will provide a tool and a service to those laboratories to allow quick screening of potentially useful genes in citrus trees. 1)Improve the transient expression vector based on citrus tristeza virus (CTV)to be able to express more than one foreign gene or peptide simultaneously. The foreign gene products can then be expressed systemically in small citrus trees and examined for in vivo efficacy. The advantage of this system is that genes can be tested in a range of citrus varieties and species in cycles of weeks instead of years. This technology is required for rapid progress to be made in controlling these diseases. 2) Develop effective agro-inoculation of citrus plants with the vector. Presently, methods to infect citrus trees with recombinant CTV are time consuming and labor intensive. 3) Screen promising antibacterial peptides against citrus canker in citrus trees under simulated field conditions.

Approach:
Develop a coordinated, multiphased research effort on Citrus Tristeza Virus and other exotic citrus diseases in Florida with University of Florida (Lake Alfred, Gainesville) and ARS personnel (Ft. Pierce and Beltsville).