Endophytic bacterial engineering: a novel approach for pine wilt disease management in Pinus massoniana

BACKGROUND Pine wilt disease (PWD) is a globally devastating forest disease caused by the pine wood nematode ( Bursaphelenchus xylophilus ). Chemical control plays a role in the prevention and control of PWD, but it also raises concerns regarding environmental safety and drug resistance. Seeking novel strategies and technologies to manage PWD has long been a matter of concern. The aim of this study was to increase the resistance of pine trees to PWD through the application of the transgenic engineered bacterium Pseudomonas koreensis BM06‐P60. RESULTS A dominant endophytic bacterium, P. koreensis BM06, was isolated from healthy stems of Pinus massoniana . This strain was capable of efficiently and stably colonizing P. massoniana and significantly promoted the growth of its seedlings. The purified peptidase P60 protein was able to disintegrate the nematode cuticle, damage the intestinal tissues, and exert adverse effects on the nematodes. The engineered strain BM06‐P60, which expresses peptidase P60, exhibited significantly enhanced nematicidal activity. Greenhouse disease control tests demonstrated that the engineered strain BM06‐P60 exhibited 70% efficacy against PWD. Preliminary ecological safety evaluations indicated that BM06‐P60 is a promising and safe candidate for biocontrol engineering. CONCLUSION The application of the engineered strain BM06‐P60 effectively controls PWD. This study provides a novel microbial resource for the prevention and control of PWD.