Submitted to: American Phytopathological Society Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 3/12/2004
Publication Date: 7/31/2004
Citation: Francis-Mastalli, F., Civerolo, E.L., Lin, H. 2004. PCR based systems for the detection, differentiation and quantification of Xylella fastidiosa strains. Phytopathology. 94(6):S31.
Technical Abstract: The overall goal of this work is to develop reliable clinical detection systems protocols for identification and quantification of Xylella fastidiosa (Xf) strains in naturally-occurring single or mixed infections in different hosts, as well as in insect vectors. Five PCR systems were developed based on the currently available genomic sequences of four Xf strains: Pierce's disease of grapevine (PD), almond leaf scorch (ALS), oleander leaf scorch (OLS) and citrus variegated chlorosis (CVC). One system, based on primer pair HL5/HL6 and a probe labeled with FAM as a fluorescent dye, detected and differentiated three Xf strains (PD, ALS, OLS), and Xf-CVC DNA. Four additional primer systems were developed for standard PCR and Real Time PCR using Taq-Man probes labeled with fluorochromes with different wavelength emissions. Each pair of primers can be used for standard PCR detection or combined with fluorochrome-labeled probes for quantitative assay. These systems were able to specifically differentiate each strain (whole bacteria or DNA) in suspensions containing mixtures of Xf strains and also in DNA preparations from field collected samples.