Fig. 5. Residence time (mean ± s.e.m.) of N. vitripennis females and males in odor and control fields of a two-choice olfactometer. Females were either virgin or mated and tested 5 min, 24 h or 6 days after copulation. The 6-day ones had the opportunity to oviposit. Tested males had no copulation experience. Odor fields were treated with (A) one male equivalent (eq.) of natural 5-hydroxy-4-decanolide (HDL; experiment 1), or (B) synthetic (4R,5R)- and (4R,5S)-HDL (ratio 1:1.3) at doses of 80 or 160 ng (experiment 2). Control fields were treated with the pure solvent. Asterisks indicate significant differences (*P<0.05, ***P<0.001); NS, not significant (t-test for dependent samples, N=20).