Monochamus Saltuarius Endangers Pinus tabuliformis Carr. and Carries Bursaphelenchus xylophilus (Steiner and Buhrer) in China

Abstract

The pinewood nematode (Bursaphelenchus xylophilus) can cause fatal damage to trees and is transmitted by the vector species of the Monochamus genus. In December 2017, pinewood nematodes were found to be harming a large plot of pine trees, Pinus tabuliformis, in a new region with an average annual temperature of 6.7 °C in China. However, the vector insects were unknown and urgently needed to be identified. Hence, in April 2018, we collected wood sections of P. tabuliformis trees that had died from pine wilt disease. All 127 longhorn beetles that emerged from the P. tabuliformis samples were identified as Monochamus saltuarius, and the nematodes they carried were fourth-stage dispersal juveniles of the pinewood nematode. The carrier rate of pinewood nematodes in the M. saltuarius population was 58.3%, and the average carrying capacity was 642.4 ± 89.3. In the same P. tabuliformis plot, 742 M. saltuarius beetles were collected from hormone traps. Our results revealed that M. saltuarius can damage P. tabuliformis and is a new vector species of the pinewood nematode in China. These findings can inform the prevention and control of pinewood nematode damage to pine forests.