亚洲玉米螟卵对3种赤眼蜂的适合性比较

Comparison study of suitability of Ostrinia furnacalis egg for three Trichogramma species

观察研究了以米蛾卵和亚洲玉米螟卵为寄主时 ,玉米螟赤眼蜂 (Trichogrammaostriniae)、拟澳洲赤眼蜂(T confusum)、松毛虫赤眼蜂 (T dendrolimi)等 3种赤眼蜂的寄生发生及羽化情况。结果发现 :以米蛾卵为寄主时 ,3种赤眼蜂的寄生发生率均为 10 0 % ,其中寄生卵粒数、子代蜂数及子代蜂的羽化率以松毛虫赤眼蜂最高 ;蜂的死亡率以玉米螟赤眼蜂最高 ,达 10 4 2 % ,且死于预蛹期以前的蜂所占比例显著高于拟澳洲赤眼蜂和松毛虫赤眼蜂。以亚洲玉米螟卵为寄主时 ,玉米螟赤眼蜂的寄生发生率和寄生卵粒数显著高于其它两种蜂 ,松毛虫赤眼蜂的寄生发生率显著低于其它两种蜂。可以认为 ,亚洲玉米螟卵是玉米螟赤眼蜂的适宜寄主 ,是拟澳洲赤眼蜂的次适寄主 ,是松毛虫赤眼蜂的不适寄主。

Experiments were carried out to evaluate the parasitism and the fitness of three species of Trichogramma,T.ostriniae,T.confusum, and T.dendrolimi on eggs of Corcyra cephalonica and Ostrinia furnacalis. All three wasps could parasitize on eggs of Corcyra cephalonica successfully at a rate of 100%.The only difference was that T.dendrolimi parasitized more eggs and produced more progeny wasps than the other two species,and T.ostriniae showed little higher natural mortality,especially during the larvae stage.When O.furnacalis eggs were provided as host,96% T.ostriniae could make parasitism.But for T.confusum and T.dendrolimi, only 20 78% and 3 28% wasps,respectively,made parasitism.The results suggest that Ostrinia furnacalis egg was a good host for T.ostriniae, intermediate one for confusum and poor one for T.dendrolimi.