"The flies are unable to distinguish the lily from rotting fruit they are deceived by the lily because it imitates the yeasty odor although it does not offer yeast as food," says Johannes Stkl. The insects' involuntary pollination service is not even rewarded; in fact, just the opposite is true: the flies are trapped in the flower until it opens again after 24 hours - and they stay hungry.
Using transgenic flies expressing a calcium sensitive activity reporter, Silke Sachse, leader of the Functional Imaging Group, and her PhD student Antonia Strutz, were able to trace the activity of the yeast odor stimulants in the brains of the flies. This functional imaging technology helped to demonstrate that eleven different odorant receptors were activated. Because different drosophilid species were deceived by the Solomon's Lily, it seemed likely that evolutionary ancient odorant receptors were among the activated ones, and this turned out to be the case. "The sequence of two of the odorant receptors, namely Or42b and Or92a, is highly conserved. These genes are likely to have a critical function as "yeast detectors" across most, if not all drosophilid flies," explains Bill Hansson, director at the institute.
Is keeping a Solomon's lily now the ultimate solution to rid your kitchen of flies? "Well, since they only flower once per year, and then only for a few hours, a cup of vinegar is still a better option. However, during the hours it flowers, I can assure you there will be no flies left in your kitchen!" says Marcus Stensmyr.
|Contact: Bill S. Hansson|
Max Planck Institute for Chemical Ecology