BEHAVIORAL AND ELECTROPHYSIOLOGICAL RESPONSES OF THE MEXICAN FRUIT FLY (DIPTERA: TEPHRITIDAE) TO GUAVA VOLATILES

The behavioral and electrophysiological responses of males and females of the Mexican fruit fly Anastrepha ludens (Loew) to guava (Psidium guajava L.) volatiles were investigated in laboratory tests. Males and females were significantly more attracted and landed more often on guava fruits than yellow spheres used as control in the wind tunnel. Also, both sexes were more attracted to Porapak Q extracts of guava than to solvent controls. Gas chromatography-electroantennographic detection (GC-EAD) analysis of the behaviorally active extracts showed that consistently eight and seven compounds elicited antennal response from male and female, respectively. The compounds were identified by gas chromatography-mass spectrometry (GC-MS) as ethyl butyrate, (E)-3-hexenol, (Z)-3-hexenol, hexanol, ethyl hexanoate, hexyl acetate, (Z)-3-hexenyl butyrate and ethyl octanoate. The electrophysiological activity of the identified compounds at three different doses was evaluated with electroantennography (EAG). An analysis of covariance of the EAG amplitude revealed that synthetic chemicals, sex, dose, and the synthetic chemical × dose interaction significantly influence the antennal response of A. ludens. Males and females were significantly more attracted to septa loaded with the eight-component synthetic blend compared to solvent controls in the wind tunnel.