Abstract:Ficus pumila L. var. pumila (FPP) and F. pumila L. var. awkeotsang (Makino) Corner (FPA) are evergreen climbing dioecious fig plants, the relationship that between two kinds of fig trees is the original variant and variant. FPP and FPA are respectively pollinated by their own obligated pollinator, and the relationship between two pollinating wasps is determined by the cryptic species. FPP and FPA built obligate symbiotic relationships with their specific pollinating wasps. Figs volatiles play an important role in the maintenance of pollinating wasps and their host symbiotic relationship. Pollinating wasps can follow the volatiles of specific host female phase figs, and enter figs for oviposition and pollination. In this study, we used a Y-tube olfactometer to test the behavioral responses of Wiebesia pumilae (Hill) Wiebes, the pollinating wasps of FPP and FPA, to the female phase fig volatiles of FPP and FPA. The results showed that: (1) the size of female phase figs had no significant effect on the behavioral responses of W. pumilae; both female and male receptive phases of large and small type figs of FFP volatiles had a strong attractiveness to its obligate pollinator; (2) the concentration of fig volatiles had a significant effect on W. pumilae behavior, both female and male receptive phase figs of FPA and FPP volatiles had a threshold response phenomenon on their obligate pollinators; when the volatile concentrations did not exceed the threshold value with the increase in volatile concentration, the attraction of pollinators increased; however, if the volatile concentration exceeded the threshold value, the attraction of pollinators decreased; (3) the pollinating wasps of FPP to both female and male low concentration female phase fig volatiles of FPA and pollinating wasps of FPA to both male and female low concentration female phase figs volatiles of FPP were neither attracted nor deterred. The pollinating wasps of FPA showed significant preference for both male and female high concentration female phase fig volatiles of FPP, whereas the pollinator of FPP was deterred by both male and female high concentration phase figs volatiles of FPA. Therefore, the pollinating wasps of FPA and FPP showed asymmetric host specificity. It is possible that the pollinating wasps of FPA enter female and male phase figs of FPP for pollination and oviposition, respectively; however, in Fuzhou, it is difficult for the pollinating wasps of FPP to enter the female and male phase figs of FPA for pollination and oviposition, respectively. Our results will provide the scientific basis for the studies on chemical signaling mechanisms of fig-wasp mutualism and FPA cultivation.