摘要
内寄生蜂寄生可能会引起寄主的寄生性去势。对小菜蛾Plutella xylostella与菜蛾啮小蜂Oomyzus sokolowskiiKurdumov(膜翅目:姬小蜂科)、半闭弯尾姬蜂Diadegma semiclausumHell啨n(膜翅目:姬蜂科)、菜蛾盘绒茧蜂Cotesiaplutellae(Kurdj.)(膜翅目:茧蜂科)3个寄生体系,利用形态学方法和蛋白质技术,研究了寄生对小菜蛾幼虫精子发生的影响。结果表明:菜蛾啮小蜂寄生对寄主的精子发生过程没有影响。半闭弯尾姬蜂寄生造成寄主精母细胞的细胞核畸形,精细胞的染色质超浓缩并趋向核膜,但能形成少量的精子;半闭弯尾姬蜂寄生会导致寄主精巢总蛋白的含量显著下降。菜蛾盘绒茧蜂寄生对小菜蛾幼虫精子发生的抑制程度最强,被寄生寄主的精母细胞出现肿胀,核膜皱缩,胞质中的线粒体发生病变;精细胞的染色体也出现超浓缩并趋向核膜,大量的精子溶解,无正常的精子形成;其精巢总蛋白含量的下降程度比姬蜂寄生的更为明显,且导致分子量为63.4kD的主蛋白缺失。
Parasitic castration often takes place in host insects parasitized by endoparasitoids. Using the morphological method and protein technology, we studied the effects of parasitization on the testicular development of Plutella xylostella parasitized by Oomyzus sokolowskii Kurdumov （Hymenoptera： Eulophidae）, Diadegma semiclausum Hell6n （ Hymenoptera ： Ichneumonidae） or Cotesia plutellae （ Kurdj. ） （ Hymenoptera ： Braconidae）, respectively. The results showed that neither the testicular appearance and structure of the host larvae, nor the content and categories of proteins extracted from its host testes changed compared with the control when the host larvae were parasitized by O. sokolowskii. However, when parasitized by D. semiclausum, the testicular development of P. xylostella larvae was adversely affected with deformed nuclei and condensation of chromatin observed in germ cells, but some elongated sperms could still come into being in the testes of parasitized larvae; the content of proteins in a pair of testes decreased significantly after parasitization, but the constitution of proteins had no alteration compared with that of the control. The most pronounced parasitic castration was observed in the host larvae parasitized by C. plutellae, spermatogenesis in the parasitized larvae was inhibited completely, many degenerated testicular cells and the debris of sperm were found in the atrophic testes, and the content of total proteins in these testes sharply declined. Furthermore, SDS-PAGE profiles of testicular total proteins revealed that a protein of an approximate molecular mass of 63.4 kD was absent in testes of P. xylostella larvae parasitized by C. plutellae compared with the non-parasitized host larvae.
出处
《昆虫学报》
CAS
CSCD
北大核心
2006年第6期908-917,共10页
Acta Entomologica Sinica
基金
国家自然科学基金项目(30471168
30370959)
教育部新世纪优秀人才支持计划资助项目(NCET-04-0521)
教育部创新团队项目(IRT0355)
关键词
内寄生蜂
菜蛾啮小蜂
半闭弯尾姬蜂
菜蛾盘绒茧蜂
小菜蛾
精子发生
寄生性去势
Endoparasitoids
Oomyzus sokolowskii
Diadegma semiclausum
Cotesia plutellae
Plutella xylostella
spermatogenesis
parasitic castration
