END-POINT DETECTION OF PIERCE'S DISEASE IN WINE GRAPES USING RAPID TEST KITS
Macallister, C.1; Eason, N.2; Fuder, J.3; Williams, J.4; Scaduto, J.5; Patrick, S.6; Hoppers, A.7; Holloway, A.8; Marcellino, P.91County Extension Coordinator, University of Georgia Extension, Dawsonville, GA, 30534
2County Extension Coordinator, University of Georgia Extension, Cleveland, GA, 30528
3County Extension Agent, University of Georgia Extension, Canton, GA, 30114
4County Extension Coordinator, University of Georgia Extension, Hiawassee, GA, 30546
5County Extension Coordinator, University of Georgia Extension, Clayton, GA, 30525
6County Extension Coordinator, University of Georgia Extension, Clarkesville, GA, 30523
7County Extension Coordinator, University of Georgia Extension, Blue Ridge, GA, 30513
8County Extension Agent, University of Georgia Extension, Winder, GA, 30680
9County Extension Agent, University of Georgia Extension, Elberton, GA, 30635
Abstract:
Pierce’s disease (PD), caused by the bacterium Xyllela fastidiosa, is a major challenge to sustainable wine grape production in Georgia. Pierce’s disease is vectored by insects which can rapidly spread the disease throughout a vineyard. Cold winters help to moderate the effects of PD, however, mild winter temperatures in recent years have led to increased spread of PD in north Georgia. When PD is detected in a vine, the recommended method of treatment is immediate vine removal to prohibit the spread of inoculum to surrounding vines. Currently, established methods of disease identification are diagnosis of visual symptoms and expensive multi-day laboratory testing for confirmation. Recent advances in technology have allowed for rapid detection test kits. Agdia’s AmplifyRP rapid detection kits were purchased for a pilot program, and were housed in the Lumpkin County and White County Extension offices. UGA Extension agents and grape producers sent suspected PD-positive petioles for same-day confirmation. During the growing seasons of 2018 and 2019, fifty-five samples were taken from sixteen vineyards in eleven north Georgia counties. Samples were collected from fourteen different grape cultivars. Further testing of the AmplifyRP rapid detection kits in future growing seasons will help determine their real-world functionality and suitability for grower use.