Research On The Volatile Infochemicals For The Host Location Of Aprostocetus Fkutai, An Egg Parasitoid Of Apriona Germari

Aprostocetus fukutai is an egg parasitoid of Apriona germari. We designed three steps to find the infochemicals for the host location of the wasp. First of all, we devised several treatement that maybe include the volatiles in the process, and determine the behavior response of the wasp to each treatment by Y-olfactometer, then we collected and indentified the volatiles of intact mulberry shoot, host feeding damaged mulberry shoot, and host oviposited mulberry shoot. Several compounds that are likely to be the allure materials are choosed by comparing differences of volatiles from different treatment of shoots in quality and quantity. Finally three compounds are confirmed in the host location of the wasp through the farther study of EAG and behavior determination. The concrete results of the study are as follows:1. The healthy plant(HP) and the system damaged(SD) plant are all attractive to the wasp significantly; the mechanical wounding plant(MW)and the feeding damaged plant(FD) attracted the wasps more clearly; the wasps strongly tend to the integer plant and the oviposited plant(OP). There are no significant differences between the HP and the MW; compared with the MW, FD are more attractive to the wasps. But the wasps tend to the OP much easier than the FD. The volatiles from female and male host insects Apriona germari are not attractive to the wasps, but the frass of the host is attractive to the wasp.2.44 compounds are analysized by TCT-GC/MS, mainly include alcohols, aldehydes, ketones, aromatic compounds, terpenoids and nitrogenous compounds. The content of terpenoids in the volatiles are high, and becomes the maximum in volatile components of feeding damaged plants.There are 27 compounds in the volatiles of the host frass, which consists of hydrocarbons, alcohols, aldehydes, ketones, terpenoids, aromatic compounds and nstrogenous compounds. The mainly compounds are hydrocarbons, and the relative content of 1, 6-heptadiyne is highest, which is the peculiar material in the volatiles of the host frass. The components of the volatiles of the frass are considerably different with those from the host plant; there are only two chemicals in common, benzaldehyde andα-pinene.3. The EAG response of the wasps toβ-pinene, trans-2-hexenal and Z-3-hexenyl acetate indicates that the responses are most high when the concentration of the standard sample are 1％, and decreased along with the concentration decreasing. On the contrast, the relative EAG value of the wasp toα-terpinene, linalool and myrcene are different, and the response are most highly when the concentration of the standard sample are 0.01％, and increased along with the concentration increasing.The bioassay reaserch indicates that myrcene(0.01％), linalool(0.01％) and Z-3-hexenyl acetate(1％) attracte the wasp significantly, but the three concentration ofβ-pinene, trans-2-hexenal andα-terpinene are not bioactive chemicals of the wasps.