Olfactory responses of Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae) to dried apricot volatiles

Dried apricot is one of the stored fruit most endangered to be infested by the Indianmeal moth, Plodia interpunctella (Hübner). The aim of the present study was to identify volatile compounds from dried apricot that elicit an electrophysiological response in P. interpunctella adults. The volatiles were collected from the headspace of a glass vial with dried apricots using closed-loop-stripping analysis. Measurement by coupled gas chromatography-mass spectrometry together with an electroantennographic detector (GCMS/EAD) revealed that ten volatile compounds were consistently EAG-active. They were representatives of six different groups of organic compounds. These were four alcohols (1-butanol, 1-pentanol, 1-hexanol, 3-methyl-1-butanol), two esters (ethyl benzoate and 3-methyl-1-butanol acetate), one acid (acetic acid), one ketone (3-hydroxy-2-butanone), one pyrazine derivative (trimethylpyrazine) and one benzenoid compound (benzyl alcohol). In general, antennae of females responded more strongly than those of males. These EAGactive compounds can be considered as olfactory cues for P. interpunctella. They will be used in behavioral bioassays in order to determine whether they are attractive, or repellent towards the moth.