寄主及寄主食物对雅脊金小蜂子代性比、体型和翅型的影响

通过三级营养关系的传递,研究不同寄主食物和寄主对雅脊金小蜂Theocolax elegans(Westwood)子代性比、体型和翅型的影响。结果表明:雅脊金小蜂寄生小麦粒中的玉米象Sitophilus zeamais(Motschulsky)或米象Sitophilus oryzae(L.)的子代蜂量均显著高于寄生玉米粒中的玉米象或米象的子代蜂量;寄生小麦粒中的米象与玉米象的蜂量之间差异不显著,雌雄性比之间也差异不显著。子代雌蜂个体的体长均显著长于雄蜂的体长;但在寄生玉米粒中的米象时,其子代雌蜂和雄蜂的个体大小是最小的。长翅型雅脊金小蜂在寄生小麦粒中的米象或玉米象时,其子代长翅型的个体数量显著多于寄生于玉米粒中的米象或玉米象的子代长翅型个体数量。因此,用小麦粒中的米象或玉米象来繁殖雅脊金小蜂较之用玉米粒中的玉米象或米象的繁殖效率更高。

Effect of hosts and food of hosts on sex ratio, body size and wing form of progeny of Theocolax elegans

The sex ratio, body size and wing forms of progeny of parasitoid, Theocolax elegans ( Westwood) , feeding on the rice weevil, Sitophilus oryzae (L.) or maize weevil, Sitophilus zeamails (Motschulsky) in wheat or maize, were investigated through trophic interaction among grains, grain pests, and parasitoids. The results showed that the amount of parasitoids offspring in both rice weevil and maize weevil feeding on rice was significantly higher than that on mzize. There was no significant difference of amount of offspring and sex ratio between rice weevil and maize weevil in rice. The body length of female offspring of T. Elegans was significantly longer than of males. When parasitizing in rice weevil feeding on maize, the body size of both females and males was the minimum. When long-winged T. Elegans parasitized weevils in rice, the amoun of long-winged progeny was significantly higher than those in weevils in maize. It indicated that T. Elegans reproduced better in weevils feeding on rice than that on mzize.