Volatiles from wattles of Pinus massoniana and EAG responses of the adult Monochamus alternatus to the identified chemicals

The volatiles from wattles of Pinus massoniana Lamb. were determined by gas chromatography-mass spectrometry (GC-MS). The results showed that there were eight constituents in volatiles of one-, two-and three-year-old wattles of P. massoniana, which were consisted of α-pinene, camphene, β-pinene, myrcene, limonene, β-phellandrene, terpinolene and β-caryophyllene. But relative contents of these chemicals varied with wattle ages, with considerable difference in α-pinene, camphene, β-pinene, limonene, terpinolene and β-caryophyllene. The relative contents of α-pinene, camphene and terpinolene in one-year-old wattles were the least, which was 20.81%, 0.43% and 4.74% respectively. Whereas, the relative contents of β-pinene, myrcene and limonene were the most, which was 12.37%, 4.33% and 4.53% respectively. Electroantennogram (EAG) responses of the adult Monochamus alternatus Hope to these identified chemicals were tested and α-pinene caused maximum EAG responses, and β-caryophyllene the least.