两种寄生蜂的卵巢结构与卵成熟特点初步观察

Ovary structures of two parasitic wasps, Microplitis bicoloratus and Diglyhus isaea.

对斜纹夜蛾的内寄生蜂双斑侧沟茧蜂MicroplitisbicoloratusChen和南美斑潜蝇的外寄生蜂潜蝇姬小蜂Diglyhusisaea(Walker)的卵巢结构进行了研究。双斑侧沟茧蜂的2个卵巢管底部膨大有大量的卵,通过凹陷的颈部与萼区相连接,在萼区里大量成熟待产的卵浸泡在萼液中。产卵量随产卵时间延长而降低,在日产卵实验中,日产卵量202(±114SE),从1000至1800每2h的产卵量分别占日产卵量的38,32,17和13%;在一生产卵量实验中,9d产卵期,每头雌峰一生平均产卵量为502(±78SE)粒,第1d产卵量占一生总产卵量的42%。潜蝇姬小蜂的每个卵巢由3条卵巢管组成,每条输卵管中仅有1粒成熟卵,整个卵巢中只有6粒成熟卵,每次产卵数不超过6粒。结果表明,M.bicoloratus是早熟卵(proovigenic)类昆虫;D.isaea是同步卵(synovigenic)类昆虫。

Ovary structures of endoparasitoid Microplitis bicoloratus and ectoparasitoid Diglyhus isaea were studied in this paper. M.bicoloratus had two ovaries and a lower huge region of ovariole of M.bicoloratus containing egg mass. Mature eggs were kept in the calyx fluid of calyx region. Oviposition was lower and lower according to the time of laying eggs. In the day oviposition experiments, a female laid 20.2(±1.14?SE)eggs in average. Oviposition, every 2 hours from 10:00 to 18:00 yielded respectively 38,32,17 and 13% in total eggs. A female laid 50.2(±7.8?SE)eggs in average in whole oviposition stage. The first day of oviposition gave the highest number, in 42% of total eggs in the whole 9 days. Diglyhus isaea had two ovaries and each had three ovarioles. A ovariole only contains one mature egg at one time. So, a female could have six mature eggs and laid six eggs. These results indicated that M. bicoloratus belonged to pro-ovigenic insect, while D. isaea belonged to synovigenic insect.