Diel rhythm of volatile emissions of males and females of the peach fruit fly Bactrocera zonata

• Published in: Journal of insect physiology 2020-01, Vol.120, p.103970-103970, Article 103970
• Main Authors: Levi-Zada, A., Levy, A., Rempoulakis, P., Fefer, D., Steiner, S., Gazit, Y., Nestel, D., Yuval, B., Byers, J.A.
• Format: Article
• Language: English
• Subjects: Animals; Bactrocera zonata; Circadian Rhythm; Diurnal rhythm; EAG; Female; Male; Pheromones - metabolism; Pyrazines - metabolism; Sequential SPME/GC–MS analysis; Sex Factors; Tephritidae; Tephritidae - metabolism; Volatile Organic Compounds - metabolism
• ISSN: 0022-1910; 1879-1611
• DOI: 10.1016/j.jinsphys.2019.103970

[Display omitted] •Bactrocera zonata fruit flies release volatiles in diurnal and age related patterns.•Males release mainly pyrazines, while females release spiroacetals and ethyl esters.•Volatile emissions peak at dusk, coinciding with the period of sexual activity.•Sensory responses to the volatiles were measured by electroantennographic analysis. Fruit flies in the genus Bactrocera are among the most destructive insect pests of fruits and vegetables throughout the world. A number of studies have identified volatiles from fruit flies, but few reports have demonstrated behavioral effects or sensitivities of fly antennae to these compounds. We applied a recently developed method of automated headspace analysis using SPME (Solid Phase Microextraction) fibers and GC–MS (gas chromatography mass spectrometry), termed SSGA, to reveal volatiles specific to each sex of B. zonata that are emitted in a diel periodicity. The volatiles released primarily at dusk were identified by GC–MS and chemical syntheses as several spiroacetals, pyrazines, and ethyl esters. Solvent extraction of male rectal glands or airborne collections from each sex, followed by GC–MS, showed that certain of the volatiles increase or decrease in quantity sex-specifically with age of the flies. Electroantennographic (EAG) analysis of dose-response indicates differences in sensitivities of male and female antenna to the various volatiles. Our study provides a comprehensive analysis of the volatile chemicals produced and released by B. zonata and their antennal responses. The possible pheromone and semiochemical roles of the various volatiles released by each sex and the difficulties of establishing behavioral functions are discussed.