两种金小蜂毒液对菜粉蝶蛹血细胞延展、存活及包囊作用的影响

活体微注射测定结果表明，将0.5毒囊当量（venom reservoir equivalent, VRE）的蝶蛹金小蜂毒液注射于其寄主菜粉蝶蛹体内，注射后4～24 h寄主浆血细胞和颗粒血细胞的延展、存活和对Sephadex A50微珠的包囊能力显著下降；以0.002～0.02 VRE/μL的该蜂毒液处理其离体寄主血细胞均能产生同样的生理效应。该毒液抑制90%菜粉蝶蛹浆血细胞和颗粒血细胞延展的浓度各为0.00076 VRE/μL和0.00804 VRE/μL。可见，蝶蛹金小蜂毒液能显著抑制其寄主血细胞的延展和包囊作用，并导致血细胞的死亡。然而，同样条件下丽蝇蛹集金小蜂毒液对其非自然寄主菜粉蝶蛹的血细胞延展、存活和包囊作用则无任何效应。可见，寄生蜂毒液的生理作用具有明显的寄主特异性。

Effects of venom from two pteromalid wasps Pteromalus puparum and Nasonia vitripennis (Hymenoptera:Pteromalidae ) on the spreading, viability and encapsulation capacity of Pieris rapae hemocytes

The effects on host hemocytes with the microinjection with venom from an endoparasitoid, Pteromalus puparum (Hymenoptera: Pteromalidae) into its host pupae of Pieris rapae (Lepidoptera: Pieridae) in vivo were bioassayed. The results indicated that the venom at the dose of 0.5 venom reservoir equivalent (VRE) per host pupa was enough to significantly reduce the spreading and viability of host plasmatocytes and granular cells as well as the capability of host hemocytes to encapsulate Sephadex A-50 beads at 4 h and 24 h after injection. The same physiological effects were performed by the venom at the dose ranging from 0.002 to 0.02 VRE/μL as P. rapae hemocytes were incubated with the venom of this parasitoid in vivo. The concentrations of the venom to inhibit 90% plasmatocytes and granular cells of P. rapae were 0.00076 VRE/μL and 0.00804 VRE/μL, respectively. The medium concentrations of the venom to inhibit encapsulation capacity of P. rapae hemocytes in vivo and in vitro were 0.0425 VRE/pupa and 0.00007 VRE/μL, respectively. Thus, it is clear that P. puparum venom has the physiological function of markedly inhibiting the spreading and encapsulation capacity of its host hemocytes and resulting in the death of its host hemocytes. In contrast, the venom from Nasonia vitripennis (Hymenoptera: Pteromalidae), an ectoparasitoid that does not parasitize P. rapae in nature, did not appear to have any effect on P. rapae hemocytes either in vivo or in vitro under the same conditions as that of the experiments with P. puparum venom. These findings suggest that the physiological effect of the venom from a defined species against insect target hemocytes has its host specificity.