白蛾黑基啮小蜂寄生对杨小舟蛾蛹血细胞包囊反应的影响及其毒液对蛹的毒性研究

Effect of parasitism of Tetrastichus nigricoxae Yang on the encapsulation response of its host,Micromelalopha troglodyta Graeser pupae and toxicity of its venom to pupal host

测定了白蛾黑基啮小蜂（Tetrastichus nigricoxae）的寄生对寄主杨小舟蛾（Micromelalopha troglodyta）蛹血细胞包囊反应的影响及其毒液对蛹的毒性。结果表明,杨小舟蛾蛹血细胞具有很强的包囊异物能力,而在白蛾黑基啮小蜂毒液的作用下这种能力会丧失,因而白蛾黑基啮小蜂的卵能在寄主蛹中顺利完成世代发育,而不被包囊。Sephadex A-25珠被注入蛹内24 h后的被包囊率高达94.00%。白蛾黑基啮小蜂寄生早期（寄生0-2 h后）不影响寄主蛹的血细胞免疫反应,寄生后期（寄生24,48 h后）杨小舟蛾蛹的血细胞免疫反应受到较大影响。γ射线辐射处理的白蛾黑基啮小蜂寄生蛹包囊能力的变化与正常白蛾黑基啮小蜂寄生蛹相似,随着寄生后时间延长而下降。白蛾黑基啮小蜂毒液对杨小舟蛾蛹的血细胞免疫反应有抑制作用,且具有一定的毒性。

Experiments were made to determine the effect of parasitism of Tetrastichus nigricoxae Yang on the encapsulation response of its host,Micromelalopha troglodyta Graeser pupae and toxicity of its venom to pupal host. We found out that the hemocyte-mediated encapsulation towards the injected Sephadex A-25 beads in the pupae of M. troglodyta was as high as94. 00%. This ability would lose after being parasitised by T. nigricoxae Yang. Parasitism did not affect in vivo encapsulation response of pupae to injected Sephadex A-25 beads in early stage（ 0 - 2 h after parasitism）,but did affect the response in later stage（ 24 and 48 h after parasitism）. Pseudoparasitism trigged by C60-γ ray irradiation influenced host＇s encapsulation in a similar way as normal parasitism,and the parsitized and pseudoparasitized pupae both died about 48 h after parasitism. The injection of venom could lead the recipient pupae to death,confirming a toxic action of venom.