Pheromone response of <i>Nasonia</i> females in a two-choice olfactometer.

<p>Residence times of (A) <i>Nasonia giraulti</i> (<i>Ng</i>) and (B–D) <i>N. vitripennis</i> (<i>Nv</i>) females in the two odour fields of a static two-choice olfactometer (see also <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0089214#pone.0089214.s001" target="_blank">Figure S1</a>) when given the choice between a solvent control (Con) and a pheromone extract (representing 100 ng total HDL) of either <i>Ng</i> (P<i>_Ng</i>, grey boxes) or <i>Nv</i> (P<i>_Nv</i>, black boxes) males. Tested females were either virgin, mated with a con- or heterospecific male under controlled conditions or collected in the moment of emergence from the host. Hosts were either infested by one species only (<i>Ng</i>, <i>Nv</i>) or multiparasitised by both species (<i>Ng</i>/<i>Nv</i>). Apart from panel (C), tested females were 1–2 days old. Box-and-whisker plots show median (horizontal line), 25–75 percent quartiles (box), maximum/minimum range (whiskers) and outliers (° >1.5× above box height; * >3× above box height) (data analysis by a Wilcoxon matched-pairs test; n = 20).