Rapid Detection Of Bersaphelenchus Xylophilus Carried By Trapped Monochamus Alternatus And Early Diagnosis Of Suspected PWN-infested Pine Trees

Pine Wilt Disease is a kind of destructive pine tree disease which is severely threatening forests safety in many countries and has caused great economic loss every year as well as imponderable ecological damage.Its causative agent,pine wood nematode {Bursaphelenchus xylophilus,PWN),is a quarantine organism at the top of the list of the pathogenic species in many countries and also listed on A2 in China.The pine wood nematode is transmitted by Monochamus alternatus,which are not only the primary vector of B.xylophilus in China but also the important stem borers of native coniferous forests.These beetle vectors transmit the PWN to new host trees via the feeding wounds and the oviposition wounds.So controlling the population of Monochamus alternatus could not only relieve direct damages but prevent B.xylophilus spreading.However it is difficult to differentiate B.xylophilus from the closely-related species B.mucronatus which is not pathogenic to pine trees under microscope for their morphological similarity,which makes the quarantine and prevention very difficult to perform.In this study we focused on M.alternatus,B.xylophilus and PWN-infested pinewood.Applying the rapid detection and early diagnosis techniques of B. xylophilus,we monitor the PWN in the adult body of M.alternatus accurately and timely.A number of M.alternatus insects were induced with the insect catchers in the epidemic region from April to September in 2008.Based on real-time PCR assay, investigated the nematodes carrying situation of the M.alternatus.Our study can effectively detect PWN isolated from trapped M.alternatus early,and help to wipe out the infectant and prevent the further spread of PWN.In this study we applied the early diagnosis tube to the PWN-infested pinewood from epidemic regions and the experiments indicated that the early diagnosis tube has effective B.xylophilus-inducing capacity.We further test the efficiency of the early diagnosis tube and the influence of temperature on its inducing capacity. Applying the early diagnosis and rapid detection method of B.xylophilus in reality successfully can effectively detect pine wilt disease in the first stage in epidemic regions widely.