Recombinase Polymerase Amplification-Lateral Flow Dipstick Assay for Rapid Detection of Based on a Newly Identified Unique Target Gene.

Pitch canker caused by the fungus is an important disease affecting pine trees in Europe and South Africa. Several countries, including China, have listed as a quarantine pathogen. Therefore, timely detection of could efficiently prevent its introduction into new areas or facilitate spread management in already infected sites. In this study, a recombinase polymerase amplification-lateral flow dipstick (RPA-LFD) assay was developed for rapid detection of based on a new target gene, , identified from whole-genome sequences. The assay was highly specific to . In fact, it exclusively detected isolates; 53 isolates of fungal and oomycete species and 2 nematodes of and were not detected. By detecting as little as 10 pg of genomic DNA in a 50-µl reaction, the RPA-LFD assay was 10 times more sensitive than conventional PCR assays. was also detected in artificially inoculated pine needles of . These results demonstrated that the developed RPA-LFD assay has the potential for rapid detection of in regions at high risk of infection. The RPA-LFD assay might serve as an alternative method for the early detection of .