Primary research on wing dimorphism of alfalfa weevil Hypera postica (Gyllenhal)

( Objective ) To explore the effect of the factors such as heredity and environment on wing dimorphism of alfalfa weevil and then provide theoretic basis to forecast its occurrence . ( Method ) Larvae were reared until becoming pupae under conditions that included different parental combinations, temperatures, larva densities and host quality statistic analysis on wing dimorphism differentiation was conducted. ( Result) The results showed that: there are significant difference in wing morph differentiation of Ft progeny pupae obtained from different parental combinations, especially in the combination when both parents were normal [long dash] wing (N x N cross) vestigial [long dash] wing pupae of Ft progeny can be as high as 94.1% ; the effect of temperature and density were also significant : the differentitation ratio of normal [long dash] wing pupae increased and vestigial [long dash] wing pupae decreased with the increasing of temperature and density; quality of hosts brought significant difference, the ratio of normal [long dash] wing pupae in the treatment of alfalfa stem were obviously high than the treatment of alfalfa leaf . ( Conclusion ) Thus, the differentiation of wing morph of alfalfa weevil were controlled by many factors.