麦蛾柔茧蜂幼虫唾液腺的显微与超微形态观察

Microscopic anatomy and ultrastructure of larval salivary glands of Habrobracon hebetor(Say)(Hymenoptera:Braconidae)

本文采用解剖学观察、显微摄影、透射电镜等方法对麦蛾柔茧蜂Habrobracon hebetor幼虫唾液腺的显微形态、超微结构以及发育特性进行了观察和分析。麦蛾柔茧蜂幼虫唾液腺为一对无色透明至乳白色的管状腺体,自口腔沿中肠两侧向后延伸,单侧腺体在中部先分支、后合并成一不规则环状,端部呈单盲管状。唾液腺管道长度随幼虫龄期增加而呈线性增长。对唾液腺切片进行超微结构观察,发现腺管由两类差异明显的单层细胞组成,Ⅰ型细胞微绒毛层较厚,胞内除有丰富的内质网和线粒体之外,还含有大量囊泡,并观察到囊泡运输分泌颗粒的现象;Ⅱ型细胞微绒毛短,胞内的内质网和线粒体数量丰富。本文研究为深入探究寄生蜂幼虫的消化生理以及寄生蜂-寄主互作机制奠定了基础。

The microscopic anatomy,ultrastructure and growth characteristics of larval salivary glands in the parasitoid wasp,Habrobracon hebetor were observed and analyzed by dissection,photomicrography and transmission electron microscope.The salivary glands of H.hebetor larvae were a pair of colorless transparent to milky white tubular glands,extending backward from the mouth along both sides of the midgut.The unilateral gland forms a large and irregular loop in the middle,and ends in the shape of a single blind tube.The length of the salivary gland duct increases linearly with the larval instar.The ultrastructural observation of salivary gland sections showed that the gland ducts were composed of two distinct types of monolayer cells.Type Ⅰ cells had thicker microvilli and contained a large number of vesicles with transporting secretory granules,besides abundant endoplasmic reticulum and mitochondria.Type Ⅱ cells had short microvilli,abundant endoplasmic reticulum and mitochondria.This study provides a basis for further exploring the digestive physiology of parasitoid larvae and the mechanism of parasitoid-host interaction.