Volatile Compounds in the Frass of Adult Chinese White Pine Beetle

Volatile compounds from phloem of healthy Chinese white pine(Pinus armandi Franch) and fresh frass of Chinese white pine beetle(Dendroctonus armandi Tsai et Li) were extracted by solid-phase microextraction and analyzed by gas chromatography-mass spectrometry(GC-MS).The results show that the most substances were sesquitertenes,followed by monoterpenes,no diterpenes were detected in frass and phloem.There was significant difference both in constituents and contents between beetle adult frass and trees phloem.The content of monoterpene was much more but the sesquitertene was less in frass of Chinese white pine beetle than those in phloem of healthy Chinese white pine.Fifteen substances such as 6,6-dimethyl-bicyclo hept-2-ene-2-carboxaldehyde,1,3,3-trimethyl-bicycloheptan-2-ol,2,3-dimethyl-tricycle [2.2.1.0(2,6)] heptane-3-methanol,and so on were detected only in adult D.armandi frass,of which eight substances such as 4,6,6-trimethyl-(1S)-bicyclehept-3-en-2-one,1,3,3-trimethyl-bicycleheptan-2-one,pallyl-anisole were only detected in female frass and 3,7-dimethyl-1,6-octadien-3-ol,2,2,3-trimethyl-3-cyclopentene-1-acetaldehyde,butylated hydroxytoluene in male frass,which provided theoretical basis to the host selection of adults D.armandi to Chinese white pine and secretion of D.armandi pheromone.