Volatiles Of Pinus Tabulaeformis And Their Biological Activities On Gravitarmata Margarotana

Pinus tabulaeformis Carr. is a widespread main wood species in China, used for soil and water conservation forest in north of China. Gravitarmata margarotana is one of the most serious coniferous pests to P. tabulaeformis. In north of Chian, the pest mainly damage P. tabulaeformis, especially in orchard and parent stand, the cone damage and loss rate is ninety percent and eighty percent respectively. Researches on their biological, ecological characterlistics and chemical insecticides control are quite enough, but the studies on their alleochemical interaction between P. tabulaeformis and Gravitarmata margarotana is poor. Nowadays, attention has been paid to the side effects of chemical insecticides control, a integrated pest management policy is presented. The advance of chemical ecology and related subjects has provided a new control approach to the integrated pest management. Accordingly, we followed the pattern of chemical ecology, after analysis on the host plant volatiles, a bioassary on the pest was done using host plant volatiles.In this paper, the volatiles of P. tabulaeformis were collected by dynamic headspace sampling and analysed by capillary gas chomatography-mass spectrometer (GC-MS) and external reference method, the electroantennogram (EAG) responses of Gravitarmata margarotana to different host plants and different parts of P. tabulaeformis were tested by EAG technique. Seven monoterpenes, camphene,β-phellandrene,τ-terpinolene, 1R-(+)-α-pinene, (-)-β-pinene,β-myrcene and R-(+)-limonene were identified and the latter four components were quantified. In Gravitarmata margarotana oviposition selection period, the total contents of volatiles in healthy needle branches were higher than healthy cone branches, and the total contents of volatiles in red cone tree were lower than green cone tree. The four components in healthy cone branches during daytime were higher than nighttime. Gravitarmata margarotana prefered to oviposit on hosts which contain lower contents of volatiles. In Gravitarmata margarotana damage period, the four components in damaged cone branches were higher than healthy cone branches, after chemical induction, the four components in healthy cone branches increased significcantly. Herbivore induction and chemical induction resulted in similar responses to P. tabulaeformis.EAG values of Gravitarmata margarotana to young shoot volatiles of Larlix gmelini, P.