Studies On Chemical Communication Effect Among Tritrophic Level: Tea Plant-Polyphagotarsonemus Latus-Anystis Sp.

In order to investigate the communication mechanism among the tritrophic level:tea plant-Polyphagotarsonemus latus-Anystis sp., as well as probe into whether the damaging by yellow mite Polyphagotarsonemus latus induces synomones emitted from the fresh tea shoots, the tea shoots with 1 bud and 2 leaves of Zhuyong 808 and Sichuanzhongxiaoye cultivars that have been growing on the reach of tea region of Chongqing City and Sichuan Province were plucked. The essential oil in tea shoots were extracted by SDE method, added into anhydrous sodium sulfate for removing water, filtrated, then concentrated by Nitrogen flow. The components in the oils were identificated by retention time on GC coupled of Mass spectrum and peak enhancement on co-injection with authentic commercial samples. Twenty-four and eighteen components respective from intact and mite-damaged shoots of Zhuyong 808 cultivar were detected. After mite damaging, the contents of methyl salicylate and benzaldehyde increased as much as 3.29 and 2.45 times of the original, respectively. Fourteen and nineteen components respective from intact and mite-damaged shoots of Sichuanzhongxiaoye cultivar were detected. After mite damaging, the contents of methyl salicylate increased as much as 3.09 times of the original, and in the mite-damaged shoots E,E-α-farnesene and E-β-ocimene were detected. It is considered that mite damaging alters the composition of volatiles of shoots, and the shoots release synomones, such as methyl salicylate and benzaldehyde.We consider that:the volatiles from intact tea plants attract Polyphagotarsonemus latus to move on the tea plants, and mediate the behaviour of the mite; after being damage by the mite, the composition and relative content of the volatiles from tea plants were altered, and such synomones as methyl salicylate and benzaldehyde were emitted a lot, which significantly attracted Anystis sp.; the infochemicals regulate the relationship among tea plant, Polyphagotarsonemus latus and Anystis sp., and maybe used to control the harmful mites on the tea plants.