| The grey tiger longicorn (GTL) (Xylotrechus rusticus L.) (Coleoptera: Cerambycidae) is a dangerous stem borer of popular, which adults oviposit on stem and the larvae damage concentratively in xylem, which result in wind-break and withered. Since it was reported at the end of 1970s in China, its damage extent aggravated gradually and the endanger areas extended constantly. It has been listed as domestic foresty plant quarantine object by the State Forestry Administration in 2005. Because the existing control measures have little effects on controlling the beetles, it is urgent to find new control methods with high efficiency. In this thesis, the types and distributions of the sensilla of GTL were studied systematically, and the electroantennogram (EAG) and behavioral responses of the inset to plant volatiles were detected using antennae electron technique and the "Y"-tube olfactormetry, which providing theoretical and practical basis for developping effective ecological control method.The research was carried out as follows: first, the typology, number and distribution of antenna] sensilla GTL were observed with scanning electron microscope. The results indicated that there were 9 types and 28 kinds of sensilla, comprising of eight kinds of sensilla basiconica, one kind of grooved peg sensilla, seven kinds of sensilla chaetica, one kind of sensilla gemmiformium, two kinds of sensilla ensiform, one kind of dentiform sensilla, one kind of hook shaped sensilla, three kinds of finger sensilla and four kinds of special sensilla, among which tiny-fork basiconica sensilla, stout basiconica sensilla, ear-shaped basiconica sensilla, head-shaped basiconica sensilla, wide chaetica sensilla, transverse chaetica sensilla, sensilla ensiform II, dentiform sensilla and wall pore beared chaetica sensilla were reported for the first time. General chaetica sensilla, general basiconica sensilla and wide chaetica sensilla took up 95% of all the sensilla number. The possible functions were discussed on the basis of the distribution, shape character of sensilla as well as the correlative references. In addition, numerous cuticular pores and some specific epidermic structures were found on the antennae epidermis.The antennae receptors of male and female insects were of sexually dimorphic difference: (1) In length, the body size of males was shorter than that of females, but the antennae was longer than that of females at an average of 0.7 mm. (2) The distribution pattern of the same sensilla differed in different sexes. (3) The number of different sensilla were different also.The electroantennogram (EAG) responses of females and males of the beetle to 10 kinds of volatiles (0.1 uL.uL-1) were tested, including salicylaldehyde from poplar, the host plants, (lR)-(+)-α-pinene, (lS)-(-)-α-pinene, (1S)-(-)-p-pinene, (+)-3-carene, phytol, ocimene, |3-Myrcene, R(-)-a-Phellandrene and turpentine from non-host plants. The results showed that,most of this 10 volatiles (0.1 fiL^L'1) could evoke obvious EAG responses (P<0.01) of the adults by contrast with the control, female insects exhibited stronger EAG responses to turpentine, salicylaldehyde, (li?)-(+)-a-pinene and (15)-(-)-a-pinene. The 10 kinds of volatiles could arose significant EAG responses (PO.01) to males besides phytol and R(-)-a-Phellandrene. As a whole, the females had stronger EAG responses to 8 kinds of volatiles than the males, both adults had no significant differences (P>0.05) to paraffin, salicylaldehyde, (li?)-(+)-a-pinene and ocimene, but the rest 7 kinds of non-host volatiles had remarkable difference.The responses and behaviors of females to different doses of turpentine, salicylaldehyde, (l/?)-(+)-a-pinene and (liS)-(-)-a-pinene were further tested according to the result of EAG responses of the females to volatiles of 0.1 uL-uL'1. With the concentration increased, the EAG response of female GTL to urpentine, salicylaldehyde and (li?)-(+)-a-pinene increased accordingly and went steady at the concentration of 0.1 uL-uL'1. When the concentration of turpentine was less than or equal to 0.1 uL-uL'1, it exhibited repellent effect to females and had the best effect (P<0.01)at 0.1 \iL-\iL\ whereas, it showed lure effect (P>0.05) at 0.2 \iL-\tL'1. As to salicylaldehyde, when lower than O.OluL-uL"1, there was no obvious directional action (F>0.05), higher than that concentration exhibited repellent action (PO.05). The females showed no distinct directional behavioral trend to (l^)-(+)-a-pinene and (15)-(-)-a-pinene.
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