GWSS DNA Extraction Using Silica Kit
Dependable detection of Xylella fastidiosa (Xf) in glassy-winged sharpshooters (GWSS) is imperative for understanding Xf epidemiology and optimizing grapevine protection strategies. In this study, we have developed methods for extracting Xf DNA from GWSS vectors and optimized a SYBR green I based real-time PCR detection protocol that is fast, consistent, and inexpensive. The Qiagen DNeasy Tissue kit (Qiagen Inc., Hercules, CA, USA) was the most efficient kit tested in our studies, having a lower detection limit of 500 cells in the presence of insect tissue. The considerably faster pre-extraction method of repeatedly flushing the foregut with lytic buffer with vacuum pressure prior to extraction using Qiagen DNeasy Tissue kit was not significantly different than whole-tissue maceration. Storage of GWSS samples at -4°C did not compromise Xf-detection capabilities.