小菜蛾蛹期寄生蜂—颈双缘姬蜂地理种群间生殖亲和性的比较研究

Comparative study on reproductive compatibility of two geographic populations of Diadromus collaris(Gravenhors) (Hym.: Ichneumonidae), a pupal parasitoid of Plutella xylostella (L.) (Lep.: Plutellidae)

对中国浙江杭州和台湾梨山 2地的颈双缘姬蜂 ,以小菜蛾蛹作寄主 ,在室内进行了群体间、个体间杂交、回交试验 ,测定比较了各组合雌蜂寄生的寄主蛹数、育出的子代蜂数及性比 .结果表明 ,除群体杂交时梨山种群子代雌性比显著较杭州种群为低、回交时 (梨♀×杭♂ ) F1♀与杭♂回交的子代性比显著较杭♀与 (杭♀×梨♂ ) F1♂回交的低外 ,其余所测定的各项生物学特性在各组合间均无显著差异 .表明杭州和梨山两地的颈双缘姬蜂在生殖上完全亲和 ,不存在生殖隔离 。

Comparative study on reproductive compatibility was conducted in laboratory between two geographic Diadromus collaris populations, one originated from Hangzhou, Zhejiang and the other from Lishan, Taiwan, China, by both mass mating and single pair mating cross, and back cross breeding experiments using the pupae of Plutella xylostella as hosts. Number of host pupae parasitized, number of progeny produced per female and sex ratio of progeny in all cross and back cross combinations were compared. The sex ratio of the population from Lishan was significantly lower than that of population from Hangzhou in mass mating cross, and the sex ratio in the combination between hybrid female produced from the cross (female of Lishan population and male of Hangzhou population) and male from Hangzhou population was significantly lower than that in the combination between female of Hangzhou population and the hybrid male produced from the cross (female of Hangzhou population and male of Lishan population) in a back cross. However, no significant differences have been detected in all other biological characteristics tested between all other cross and back cross combinations. The results show that the two geographic populations of the parasitoid still remain reproductively compatible, do not have reproductive isolation, and keep a well defined species.