Abstract:

Each Ficus species is generally pollinated by one host-specific fig wasp species, which completely depends on the fig tree for reproductive success. However, there are some exceptions in which more than one host species, subspecies, variety, or geographic type shares the same pollinator species. Studies of the reproduction and pollination traits of conspecific fig wasps in different hosts could provide an important understanding of the stabilizing mechanism of the non-specific fig-fig wasp mutualisms. This study investigated the reproduction and pollination traits of Ceratosolen emarginatus, the pollinator of Ficus auriculata in its different geographic types, auriculata-form and oligodon-form. We found a significant increase in the number of offspring and seeds as the number of foundresses increased. However, average numbers of offspring or seeds per foundress were not different in the same treatment. These results indicate that when there are fewer foundresses, interference competition is limited as to maximize available female flowers. Results also showed that irrespective of host differences, seeds were more numerous than offspring in the same treatment. This indicates that reproductive interests of figs dominate fig-wasp mutualisms, and also demonstrates that female flowers regulate the overall fig reproductive cycle. Finally, our results revealed that although the number of wasp offspring in different hosts was similar, there were more seeds in oligodon-form than in auriculata-form for equivalent foundress numbers. This suggests that the two forms may have differentiated in reproductive capacity, which implies that different host types do not affect the reproduction of fig wasps but control seed production in this species.

Key words: Ficus, fig wasps, reproduction, pollination, auriculata-form, oligodon-form