Responses of fig wasps to host plant volatile cues

Abstract

Fig wasps (Chalcidoidea; Agaonidae) are intimately associated with the 750 or so species of fig trees (Ficus, Moraceae). Each tree species is usually pollinated by a single species of wasp belonging to the subfamily Agaoninae, while other wasps of the family are parasitoids or seed predators. Previous experiments have shown that the wasps are attracted to the trees by volatiles emanating from the figs. Using fig-bearing trees and arrays of sticky traps baited with figs, we investigated the specificity of wasp attraction and its timing. The pollinators of two closely relatedFicus species were specifically attracted to figs of their host species and only at the time when figs were ready to be pollinated. Some nonpollinating fig wasps appear to respond to the same volatile cues.

Pollination and other biotic interactions in figs of Ficus eximia Schott (Moraceae)

“…Pollinating wasps and pollination -Ficus eximia pollinators are attracted to figs when female flowers are receptive (female phase). Studies have demonstrated that pollinator attraction is mediated through volatile chemicals released from figs in the receptive phase (van-Noort et al 1989, Ware et al 1993, Hossaert-McKey et al 1994, Ware & Compton 1994. The pollinator of F. eximia penetrates the ostiole crawling through the bracts, and its wings and parts of antennae usually break off during this process.…”

Pollinator sharing and gene flow among closely related sympatric dioecious fig taxa

“…The attraction of specific floral volatiles to other atypical pollinators is understandable, as the specificity of floral volatiles is usually achieved by quantitative differences in relative proportions of many common compounds, and some compounds that actively attract certain pollinators may occur in volatiles of several plants [15]. This flexibility in host preference may also provide an explanation for the atypical pollinators captured in earlier trapping studies [30,47]. Floral volatiles between two sympatric figs, F. auriculata and F. oligodon, were notably similar and shared at least three pollinator species, with the highest pollinator sharing ratio being 34.88% (table 1; electronic supplementary material, table S5 and figure S1).…”

Flower Specialization in a Passively Pollinated Monoecious Fig: A Question of Style and Stigma?

“…This specialized inflorescence is known as a syconium, and it defines the genus Ficus. When a fig's syconia are receptive, they emit scents that attract the pollinator wasps (Ware and Compton 1994;Gibernau et al 1998;Grison-Pigè et al 2002). Pollen-bearing female wasps (foundresses) enter the syconium by the ostiole, which is the bract-lined opening situated at the apex of the syconium.…”