取食寄主对潜蝇姬小蜂卵成熟和寿命的影响

Effects of Host-Feeding on Egg Maturation and Longevity of Synovigenic Parasitoid Diglyphus isaea

【目的】阐明取食寄主与潜蝇姬小蜂(Diglyphus isaea)卵成熟和寿命的关系,了解该蜂的生殖生物学,提高该蜂的生殖潜能与人工繁殖效率。【方法】通过解剖潜蝇姬小蜂的卵巢,确定日龄、寄主龄期、取食寄主对卵成熟的影响,通过生物学观察明确取食寄主能否延长雌蜂寿命。【结果】初羽化的潜蝇姬小蜂卵巢内无成熟的卵,补充蜂蜜水后,卵逐渐成熟,羽化5 d后成熟卵量最多,达7.5粒/雌蜂,6 d后雌蜂重吸收体内的卵作为营养物质,未成熟卵数量增多,达3.7粒/雌蜂;提供潜蝇姬小蜂3龄斑潜蝇(Liriomyza sativae)幼虫,24 h后卵巢内成熟卵量和产卵量均最大,分别为5.82和2.85粒;取食3龄寄主后,雌蜂成熟卵量在羽化后3、5、7 d后分别达6.8、10.3和7.2粒,显著高于取食1龄寄主和蜂蜜的雌蜂;取食对雌蜂的寿命没有显著的影响,取食1龄、3龄寄主雌蜂的平均寿命分别为28.3、29.26 d,取食蜂蜜的雌蜂平均寿命26.8 d,三者间差异不显著。【结论】取食寄主能够增加雌蜂卵巢内成熟卵量,但是取食寄主后雌蜂寿命没有延长。

【Objective】The objective of this study is to investigate the effect of host-feeding on the egg load and longevity of parasitoid Diglyphus isaea,and to understand the reproductive biology and promote the reproduction potencies of this parasitoid.【Method】 Female parasitoids were dissected to assess egg load,three factors affecting the egg loads of D.isaea females were examined.These factors are the age of adult parasitoid（i）,the host stage utilized（ii） and the size of host-feeding meal（iii）.Daily observations were provided the longevity of the host-feeding adult.【Result】 This parasitoid emerged from their hosts without mature eggs,after given only a carbohydrate diet,they began mature eggs.At day 5,the egg load was 7.5,much higher compared to others,then gradually resorbed after 6 days.The eggs load and eggs laid were significantly higher in parasitoids exposed to 3rd instar larvae of Liriomyza sativae,which were 5.82 and 2.85,respectively.This parasitoid matured more eggs when they were fed on 3rd instar larvae of host on day 3,day 5 and day 7 after emergence.The longevity of the parasitoid feeding on 1st larvae,3rd larvae and honey feeding was 28.3,29.26 and 26.8 d,respectively,and no significant difference between them.【Conclusion】 Host feeding would increase the egg maturation,not prolong the longevity of the parasitoid D.isaea.