哈氏啮小蜂的产卵选择行为

Oviposition preference of Tetrastichus hagenowii(Hymenoptera:Eulophidae)

哈氏啮小蜂对美洲大蠊卵荚的日龄具有识别能力.该蜂能寄生1-20日龄的卵荚,但偏爱寄生1-3日龄的卵荚.该雌蜂对卵荚的攻击力和产卵数随着卵荚日龄的增加而降低,其雌蜂产卵管在60 s内插入5-10日龄的卵荚次数是插入1-3日龄卵荚次数的3倍多.哈氏啮小蜂雌蜂能辨别已寄生和未寄生美洲大蠊卵荚.该蜂对已寄生和未寄生卵荚的攻击率均为100%,该雌蜂产卵管在60 s内对已寄生卵荚的插入次数是对未寄生卵荚插入次数的3倍多,插入1次未寄生卵荚需要的时间是插入1次已寄生卵荚需要时间的5倍多.在同时提供已寄生和未寄生卵荚时,雌蜂选择未寄生卵荚产卵.

It was showed that Tetrastichus hagenowii （Ratzeburg） could distinguish oothecal age of Periplaneta americana （Linnaens）. T. hagenowii could parasitize in 1 -20 day-old oothecae, but preferred 1 -3 day-old oothecae. The female adults＇aggression ability and oviposition quantity of T. hagenowii on oothecae decreased with increasing of oothecal age, the ovipositor inserting times on 5 - 10 day-old oothecae was 3 times more than that on 1 - 3 day-old oothecae. Female adults of T. hagenowii could discriminate parasitized and unparasitized oothecae of P. amer/cana. The aggression percentages on parasitized and unparasitized oothecae were 100%, the ovipositor inserting times on parasitized onthecae was 3 times more than on unparasitized oothecae, while the time for ovipositor inserting on unparasitized oothecae each time was 5 times more than that on parasitized oothecae. If parasitized and unparasitized oothecae were provided simultaneously, female adults of T. hagenowii preferred to oviposite on unparasifized oothecae.