DETECTION OF STRAWBERRY PATHOGENS BY REAL-TIME PCR

Real-time PCR is described for use in the detection and quantification of the following strawberry pathogens: Verticillium spp. (fungi), Phytophthora cactorum (oomycete), Xanthomonas fragariae (bacteria), and Strawberry crinkle, mottle and mild yellow edge viruses. Primers for detection of these pathogens were designed by Primer Express Software (Applied Biosystems). In a first approach the use of fluorescent SYBR Green was tested in order to validate primer design for each pathogen and to be used later on to design TaqMan probes in order to increase detection and quantification specificity for those microorganisms. The sensitivity obtained was 1 bacterium per mg leaf tissue, 1 conidia of V. dahliae per mg root crown and 10^-4 ng of total RNA for SMV.