淡足侧沟茧蜂寄生对甜菜夜蛾幼虫血淋巴黑化及血细胞数量和构成的影响  

Effect of Parasitization by Microplitis pallidipes Szepligeti on the Hemolymph Melanization,Total Number and Composition of Hemocytes in the Hemolymph of Larval Spodoptera exigua(Hübner)

作　　者：季香云[1] 印杨毅[1] 万年峰[1] 蒋杰贤[1] 张浩[1] 

机构地区：[1]上海市农业科学院生态环境保护研究所,上海201403

出　　处：《中国生物防治学报》2017年第3期319-325,共7页Chinese Journal of Biological Control

基　　金：国家自然科学基金(31601641;31171904);上海市农委重点基础研究项目(2014-7-3-2)

摘　　要：为探讨寄生蜂调控寄主的免疫反应,研究了淡足侧沟茧蜂Microplitis pallidipes Szepligeti寄生对甜菜夜蛾Spodoptera exigua(Hübner)幼虫血淋巴的影响。结果表明,寄生总体上降低了寄主血淋巴的黑化率;与未被寄生幼虫相比(对照),寄生蜂寄生引起寄主血细胞总数和颗粒血细胞数量下降,且寄生后第1~3 d和6 d达到显著水平;寄生蜂寄生后第1~3 d致使寄主浆血细胞数量下降,但第4 d开始寄主桨血细胞数量增高,且寄生后第6 d显著高于对照。寄生蜂寄生也改变了寄主浆血细胞和颗粒血细胞构成比例。本研究揭示了寄生蜂寄生引起寄主血淋巴黑化和血细胞数量及其构成的变化是寄主对寄生蜂入侵产生免疫响应的结果。Spodoptera exigua （H/ibner） is a global insect pest that feeds on various agricultural crops including vegetables, cotton, and ornamentals. To investigate the immunological responses in S. exigua larvae parasitized by Microplitispallidipes Szepligeti, we observed the hemolymph melanization and the changes in the total number and composition of hemocytes using a neubauer hemocytometer. The results indicated that melanization rate in the hemolymph of the early 2nd-instars parasitized by iV/. pallidipes began to decrease gradually from day 1 after the parasitization, the ability of the parasitic wasp in inhibiting melanization increased with time after parasitization and with increase of host age; within 5-day after parasitization, the percentage ofmelanization was consistently lower in the parasitized than the control group and the difference was significant during day 2 to day 6 after parasitization. The total number ofhemocytes and the number of granular cells were lower in the parasitized than the control group on days 1, 2, 3 and 6 after parasitization. The changes in the number of plasmatocytes were different from that of granular cells, and the difference was significant on day 6 after parasitization compared to the control. The proportion of granular cells and plasmatocytes in the hemocytes also varied after parasitization, which was in inverse proportion to each other. In this study, we reveals that the blood cells play an important role in cellular immunity, and that the changes in the number and composition of blood cells can primarily reflect the immune response of insect cells to the parasitization of parasitoids.

关 键 词：甜菜夜蛾 淡足侧沟茧蜂 黑化反应 颗粒血细胞 浆血细胞 

分 类 号：S476.3[农业科学—农业昆虫与害虫防治]