【摘要】 为检验"寄主体型大小-质量假说",采取饥饿方法处理菜粉蝶(Pierisrapae)高龄幼虫,以获得体型大小(用体质量表示)差异大于同一自然地理种群内个体间差异的寄主蛹,然后供聚寄生蜂-蝶蛹金小蜂(Pteromalus puparum)寄生,观察寄生蜂在不同大小寄主蛹内的后代数量、性比以及体型大小。结果表明,蝶蛹金小蜂1次攻击产出的后代蜂数随寄主蛹体质量增加而显著增多,蛹中平均出蜂314.97头.g-1。蝶蛹金小蜂后代的雌性比例随寄主蛹质量的增大而显著提高,后代雌蜂和雄蜂的体型大小(后足胫节长度)均随寄主蛹质量的增大而显著增大。可见,蝶蛹金小蜂母蜂能够根据寄主蛹质量来调整后代数量和性比,以使后代适应度最大化。最后,就蝶蛹金小蜂产卵策略及其影响因素进行了讨论。更多还原

【Abstract】 To test the "host size-quality hypothesis",the feeding time of Pieris rapae final instar larvae was manipulated to obtain a wide range of body size(mass)of host pupae,which were then individually exposed to parasitism by gregarious parasitoid Pteromalus puparum.The offspring number of the parasitoid after a single attack was recorded,and the offspring sex ratio and body size were also observed.The results showed that the offspring production was linearly increased with increasing host pupa mass at oviposition,being 314.97 individuals per gram pupa mass on average.The proportion of offspring females and the body size(hind tibia length)of offspring males and females also increased with increasing host pupa mass.The results suggest that P.puparum could allocate its offspring number and sex ratio,so as to maximize its fitness,based on assessment of host pupa mass.The reproductive strategy of P.puparum and related factors were discussed.更多还原