Effects of Several Chemicals on the Migration Behavior of Bursaphelenchus xylophilus (Steiner &amp; Buhrer) Nickle

Xiu-Feng Shi,Qing-Tong Wang,Jian-Ren Ye,Li-Na Shi,Xiao-Lei Ding

doi:10.3390/f12060771

Abstract

The pine wood nematode (PWN), Bursaphelenchus xylophilus, that causes pine wilt disease (PWD), has severely damaged forests and ecosystems in countries of East Asia and Europe. Since the high propagation rate of PWD is the main cause of the devastating disease, it is very important to interfere with the spread of PWN mediated by its insect vector (Monochamus alternatus). In order to explore new methods and approaches for the prevention and control of pine wood nematode disease, chemicals with attraction or repellency to pine wood nematode and stable diffusion or volatilization in infected wood were screened out to interfere and hinder the pupa chamber effect, the aggregation behavior of PWN to pupa chamber in M. alternatus. In the present study, 22 chemicals were inoculated on water agar medium and infected wood to verify the tropism of PWN toward the chemicals from the aspects of attraction and repellency. The results indicate that linoleic acid, oleic acid, diacetyl and β-myrcene have attractive effects on PWN, while kerosene and β-humulene have repellent effects on PWN and are able to stably permeate and volatilize within pine trees. This research shows that some chemicals can affect the movement behavior of PWN and interfere with its migration to the pupal chamber in M. alternatus, thus reducing the dispersal efficiency of PWNs carried by insect vectors. This chemically based strategy would provide novel approaches for effective controlling of pine wilt disease.

Highlights

The long-chain fatty acids were proved to be related to the migration of Pine wood nematode (PWN) to the body and pupal chamber of its insect vector (M. alternatus) [7]
If chemicals with a significant effect on PWNs can be found, they can be used to interfere with their movement in infected wood, block their accumulation in the pupal chamber of M. alternatus, and effectively reduce the dispersal efficiency of pine wilt disease (PWD)
While this study proved that chemicals exerted a repellent effect on PWN in the infected wood, and the repellent effect was enhanced with an increasing volume

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Pine wood nematode (PWN) Bursaphelenchus xylophilus (Steiner and Buhrer, 1934). Is known to originate in North America and first spread to Japan in the early. 1900s and dispersed to other parts of Asia (China, Japan, and South Korea) and Europe (including Portugal and Spain) [1]. The infected pine trees by PWN leads to blockage of the tree vasculature, resulted in wilting symptoms and death [2]. A susceptible host can wilt and die within weeks of infection if conditions are favorable for disease development. Despite the tremendous efforts to control pine wilt disease (PWD) and quarantine wood products from infested areas, PWD has become the most destructive threat to all forests in Asia

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