WHEN FIGS WAIT FOR POLLINATORS - THE LENGTH OF FIG RECEPTIVITY

In plant species with an obligate species-specific pollinator, gamete encounter is a critical phase in the success of reproductive strategie s. One of the key factors in the success of gamete encounter, the leng th of female receptivity, has been rarely studied experimentally. In F icus species (Moraceae), each exclusively associated with its specific pollinating wasp, the receptive female phase of individual syconia wa s believed to last only a few days. This estimate, based on field obse rvations of pollinator arrivals, neglected the possibility that unpoll inated syconia may remain receptive for a prolonged period. In two dis tantly related fig species (F. carica and F. aurea), we measured exper imentally the duration of receptivity of individual syconia protected from pollinator visits. For these two species, receptivity lasted from 2 to 3 wk. Syconia pollinated at any time during this period of recep tivity are capable of setting seeds. Furthermore, it has been assumed that female syconium receptivity stops quickly after pollinator visita tion. Our experiments showed that syconia of both species are able to extend their receptive period for a few days longer when visited only by a single wasp. The demonstration of a long duration of female recep tivity has important consequences for understanding the maintenance of the fig-wasp mutualism.