Evaluation of the AmplifyRP XRT+ Kit for the Detection of Xylella fastidiosa by Recombinase Polymerase Amplification

Xylella fastidiosa is a quarantine priority pest in Europe and several other countries as it represents a major threat to many cultivated and wild plants. Early detection of the pathogen is needed to reduce potential losses and to stop the bacterial dissemination. Very few molecular methods are available for rapid field detection to identify the pathogen. Here, we evaluated a new rapid commercial detection test called AmplifyRP, based on molecular recombinase polymerase amplification (RPA). The AmplifyRP test was compared with the quantitative PCR (qPCR) Harper's assay, which represents the standard method used in most laboratories all over the world. Specificity was tested in vitro on a panel of target and nontarget strains. Additionally, the sensitivity of the RPA test was tested on X. fastidiosa genomic DNA, and the selectivity was compared between different host plant matrices spiked with X. fastidiosa cell suspensions. Although the qPCR assay showed a higher sensitivity than the RPA test, the latter appeared to be a very specific, rapid, and portable technique for which no skills are required to proceed. These findings should enable growers and inspectors to choose an appropriate diagnostic method. [Graphic: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.