高温对小地老虎和东方粘虫精子发生和形成的影响

小地老虎和东方粘虫精子发生之后，开始分化出真核精子和无核精子。当温度超过32℃时，出现大量的畸形精细胞囊，精子形成受阻，核与鞭毛明显缩短，鞭毛中微管所受影响最大。但32℃温度以下不影响真核到无核精子的发生和二叉发生的转换。由此可见，小地老虎和粘虫夏季由南向北迁飞也是一种回避高温的适应性行为。

THE EFFECTS OF RISEN TEMPERATURE ON SPERMATOGENESIS AND SPERMIOGENESIS IN AGROTIS YPSILON AND MYTHIMNA SEPARATA

The authors conducted qualitative and quantitive studies on spermatogenesis and spermiogenesis in Agrotis ypsilon and Mythimna separata with use of light and electron microscopes. At the same time, the effects of risen temperature were also studied. The results are briefly summarized as follows: There were eupyrene and apyrene sperms in A. ypsilon and M. separata after spermatogenesis. When the rearing temperature rose above 32℃, a lot of abnormal spermatid cysts appeared and spermiogenesis was arrested. In addition, the nucleus and flagellum of eupyrene spermusually shortened and a large amount of flagellum microtubles could not be produced under this temperature. But the risen temperature (<32℃ ) had no effects on dichotomous spermatogenesis and the shift of spermatogenesis from eupyrene sperms to apyrene. This phenomenon implies that the migratory flight of A. ypsilon and M.Separata in summer season from south toward north is an adaptive behavior.