Biological Characteristics And Host Location Of Eurytoma Sp (Hymennoptera:Eurytomida)

In this study, Pinus sylvestris wasps (Eurytoma sp.)was selected as object of study. We determined behavior and electroantennogram effects of five kinds of volatile substance from cones of Pinus sylvestris.var.mongolica on Eurytoma sp based on its biological characteristics. The antennel sensilla of wasps were also investigated in this study. The results showed as follow:Eurytoma sp. is one kinds of seed pests to parasitize cones of Pinus sylvestris.var.mongolica.It generally occurred one generations one year in Honghuaerji area and overwinters in the seed of cones of P.sylvestris.var.mongolica. as a full-grown larva.The rate of damaged cones destroyed by Eurytoma sp. was10%. The male was actively than female in mating behavior, and the time of mating was only several seconds. Nutritional supplements with20%honey solution can extend its life to a certain extent.The results of behavior response using five standard compound to female and male wasps was different:tert-butylamine was the most attractive one to female wasps (with a response rate of66.67%), followed by1,3,5-cycloheptatriene; while it was1,3,5-cycloheptatriene to male wasps (with a response rate of63.33%), followed by and dichloroethane. The1,3,5-cycloheptatriene only from health cones may play an important role to host location of wasps because it is more attractive to female and male wasps.The1,2-dichloroethane only from damaged cones may play an important role to inducible resistance and defense pest harm of P. sylvestris.var.mongolica because it is more evadable to female and male wasps.EAG test results were consistent with those of olfactometer tests. The female wasp antennaes showed the strongest response (EAG potential=0.1864) to2%tert-butylamine while females to1,2-dichloroethane (EAG potential=0.2922). Dose dependent relationships were found between EAG potential and1,2-dichloroethane for females, and between EAG potential and1,2-dichloroethane and1,3,5-cycloheptatriene for males, respectivelyUsing electron microscope (SEM) to the wasp antennae, which made a knee scan. wasp antennae generally has9sections constituted by scape, pedicellus, funicle(5sections)and club(2sections). Eight types of sensilla were found on the antennae of the female and male. These types are sensilla trichodea, sensilla placoclea, sensilla ampullae, Bohm bristles, sensilla chaetica, sensilla basiconca, sensilla ampullaceal and sensilla squamiformia. The male and female sensilla were different in type, quantity and size:the first five types were all found on n the antennae of the female and male. Sensilla squamiformia was only found in the last sections of male antennae and sensilla basiconca were only found in the first sections of male funicle; The sensilla placoclea on the female antennae were significantly more than male(2.56times). The sensilla trichodea on the male antennae were significantly longer than male(2.56times)The results of this study may provide theoretical basis for biological control and integrated pest management of Eurytoma sp.and technical support for the maintenance and protection species diversity and stability.