Xylem sap and xylem anatomical aspects of various Vitis genotypes in response to Pierces disease

• Author(s): Lin, Hong;
• Abstract: Current Pierce's disease studies suggest are that more than one mechanism may be responsible for differences in PD tolerance among the genotypes. In this research we are investigating if resistance/tolerance mechanisms include xylem anatomical and/or xylem sap chemical features. We use a comparative approach, examining both resistant and susceptible grape genotypes either as non-infected control plants or infected with the PD-causing bacterium Xylella fastidiosa (Xf). Experiments were conducted to characterize anatomical structures in relation to pathogen movement and to develop an in vitro bioassay technique to study the potential involvement of chemical mechanisms in PD susceptibility/resistance. Our observations indicate that aspects of xylem sap chemical composition and xylem vessel occlusion characteristics may play important roles in the degree of susceptibility/tolerance exhibited by grape genotypes. Further studies to identify the xylem sap components resulting in the described differences as well as additional analyses of the xylem occlusion characteristics and xylem anatomy are ongoing. Results will be useful for the development of solutions to the PD problem.
• Publication Date: Mar 2006
• Journal: Central Valley Biotechnology