IMPACT OF LAYERING CONTROL TACTICS ON THE SPREAD OF PIERCES DISEASE BY THE GLASSY-WINGED SHARPSHOOTER

• Author(s): Blua, Matthew; Redak, Richard;
• Abstract: Solutions to managing and controlling Pierces disease of grapes are often conceptualized as ways of breaking at least one two-way interaction among the insect, plant, and bacteria components that are required for successful disease spread and propagation. Hypothetical solutions may also involve altering the abiotic and biotic environment within which these interactions take place. On the basis of our understanding of Pierces disease epidemics, as well as other insect transmitted plant pathogen systems, one single control tactic (especially focused upon the insect) will not be sufficient to substantially reduce vector populations such that the incidence of disease is below an economically acceptable level. One management and control strategy that potentially may be utilized to limit the damage brought about by Pierces disease involves layering separate vector and disease management tactics together such that vector population densities are reduced, their interactions with grapevines are inhibited or disrupted, and the interface between grapevines and the disease organism, X. fastidiosa, is disrupted. Here we report on our efforts to simultaneously implement (i.e. layer) various control strategies currently available to limit the spread of Pierces disease transmitted by the glassy-winged sharpshooter, Homalodisca coagulata. Specifically we are investigating the efficacy in controlling Pierces disease by simultaneously (1) applying systemic insecticides aimed at reducing the number of sharpshooters invading vineyards (functioning as deterrents and inducing mortality prior to feeding); (2) applying foliar barriers (application of kaolin) such that sharpshooter landing and feeding behavior on grapevines is disrupted; (4) rapidly killing sharpshooters that actually initiate feeding on grapevines; and (5) using chemotherapy (application of metalosate) on grapevines as a prophylactic to reduce establishment of X. fastidiosa. All of these control tactics are to be employed against a backdrop of region-wide biological control of glassy-winged sharpshooters.
• Publication Date: Dec 2001
• Journal: 2001 Pierce's Disease Research Symposium