马尾松毛虫幼虫生殖系统的形态学初报

<正> 马尾松毛虫(Dendrolimns punctatus Walker)属鳞翅目、枯叶蛾科(Lepidoptera Lasiocam-pidae),它繁殖力强,迁移扩散快,经常猖獗成灾,是我国危害森林的最严重的历史性大害虫。为了防治马尾松毛虫,必须建立准确、可靠、方便的预测预报方法,掌握其种群数量动态;而昆虫的性比则是种群结构的重要特征,它对种群的数量动态有重要影响。故研究马尾松毛虫雌雄区分问题对建立上述预测、预报方法具有重要实践意义。目前尚未见到关于马尾松毛虫幼虫生殖系统的研究报道。 自1982年起,我们开始对马尾松毛虫的生殖系统进行研究。本文报道此项研究的部分结果。

MORPHOLOGY OF THE REPRODUCTIVE SYSTEM IN THE LARVAE OF DENDROLIMUS PUNCTATUS WALKER

The internal reproductive system in the 6th male larval instar of D. punctatus consists of a pair of testes, vasa deferens and the genitial cavity (Herold’s organ). Two kidney-shaped testes occur laterally just under each side of the heart in the 5th abdominal segment. From the concave middle of each testis, the vas deferens extends into the 9th segment and connects with the genitial cavity, which is a pear-shaped constructure lying on the middle of the ventral posterior margin of the 9th segment.The internal reproductive system of the 6th femae larval instar of D. punctatus comprises paired ovaries, lateral oviducts and two pairs of imaginal disks. Paired ovaries occur in the 5th abdominal segment. Their positions are similar to those of the testes of the male larvae. From the posterior ends of the ovaries the lateral oviducts pass the 6th segment and terminate on the ventral posterior margin of the 7th segment. In the 4th female larval instar two pairs of imaginal disks begin to appear in the 8th and 9th segments.Externally the concaveness of the genital cavity starts to appear in the 3rd male instar larvae while the external marks of the imaginal disks on the 8th and 9th abdomjnal segments can be recognized in the 4th female larval instar.On the basis of the morphology of the reproductive system, the methods to sex the larvae of D. punctatus are discussed,