Effect of electron beam irradiation on the pine wood nematode, Bursaphelenchus xylophilus

Abstract

Purpose Reproduction inhibition of the pine wood nematode (PWN) by electron beam (e-beam) irradiation both in vitro and in vivo was tested to determine if ionizing radiation could control the PWN by reducing survival and preventing reproduction, thus reducing the risk of pine wilt disease (PWD) spread. Materials and methods E-beam (10 MeV) irradiation treatment at different doses (0–4 kGy) was applied to PWNs in a Petri dish. Treatment of pine wood logs infested with PWNs was performed at 10 kGy. Mortality was determined by comparing the survival rates before and after irradiation treatment. DNA damage by e-beam irradiation (0–10 kGy) in the PWN was determined using the comet assay. Results E-beam irradiation increased mortality and suppressed reproduction with increasing doses. The lethal dose (LD) values (kGy) were estimated as follows: LD50 = 2.32, LD90 = 5.03, and LD99 = 9.48. E-beam irradiation of pine wood logs significantly suppressed PWN reproduction. Comets of e-beam-irradiated cells showed an increased tail DNA level and moment with an increasing dose. Conclusion This study suggests that e-beam irradiation could be used as an alternative method for the management of pine wood logs infested with PWNs.