Pollinator attraction to volatiles from virgin and pollinated host flowers in a yucca/moth obligate mutualism
Nummer: Published online 22 March
Förlag: John Wiley & Sons, Inc.
The classic obligate pollination–seed consumption mutualism between yuccas and yucca moths has been thought to be mediated by chemical cues, but empirical data on pollinator attraction to host floral volatiles in this association have been lacking. Here we show that the scent from virgin flowers of the host Yucca glauca is sufficient to attract its obligate pollinator Tegeticula yuccasella in Y-tube olfactometer tests. Interestingly, both sexes of moths were attracted to the scent stimulus. Because yucca moths mate inside host flowers, the attraction of both females and males to host floral volatiles is likely to increase encounter rates. In a second test, female moths did not discriminate between virgin and hand-pollinated flowers, indicating no post-pollination change in scent production by the host that would lead to a reduction in pollinator attraction and thereby limit exploitation of the available seeds in host flowers. However, other mechanisms that could stabilise the mutualism between T. yuccasella and its yucca hosts have already been documented, i.e. selective abortion of heavily infested flowers, and a female-derived host-marking pheromone. Headspace collection and GC–MS were used to identify the blend of floral volatiles emitted by Y. glauca, which was found to be very similar to those of two other allopatric capsular-fruited species, Y. elata and Y. filamentosa, revealing strong conservation of this trait within Yucca section Chaenocarpa.
- Biological Sciences
- Chemical ecology of obligate pollination mutualisms
- Pheromone Group
- ISSN: 1600-0706