Effectiveness of a commercial LAMP technology-based kit for rapid detection of Bursaphelenchus xylophilus in Pinus pinaster

Aim of study: To assess the usefulness of the commercial Loop-Mediated Isothermal Amplification (LAMP) kit for detecting Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle in Pinus pinaster Aiton and Pinus radiata D. Don under field conditions, thus contributing to the advancement of efficient surveillance and management strategies to combat this pathogen. Material and methods: In three different experiments, the detection rate of the B. xylophilus LAMP kit was compared to the traditional Baermann funnel technique for nematode extraction. Both detection methodologies were applied to detect B. xylophilus from different origins (Spain, Portugal, Asia, and United States) in directly inoculated P. pinaster wood chips or in samples from inoculated P. radiata and P. pinaster seedlings. Main results: The LAMP kit successfully identified B. xylophilus in samples from all studied origins. We observed a decrease in the detection rate as the number of days since inoculation increased. At 90 days after inoculation (DAI), the detection level in P. pinaster wood chips using the LAMP kit was 18%; whereas in seedlings, no nematodes were detected at 70 DAI with the LAMP kit. However, nematodes were extracted from 83% of the samples using the Baermann funnel technique, although in lower numbers than on other sampling dates. Research highlights: The commercial LAMP kit is a simple and rapid method for B. xylophilus detection, but it is not fully adapted to the field sampling requirements of the species studied.