Short range attraction of Ceratitis capitata (Diptera: Tephritidae) sterile males to six commercially available plant essential oils

Authors: Epsky, Nancy; NIOGRET, JEROME - M & M Mars Company - United States

Submitted to: Natural Volatiles & Essential Oils
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/29/2017
Publication Date: 8/1/2017
Citation: Epsky, N.D., Niogret, J. 2017. Short range attraction of Ceratitis capitata (Diptera: Tephritidae) sterile males to six commercially available plant essential oils. Natural Volatiles & Essential Oils. 4(1):1-7.

Interpretive Summary: The Mediterranean fruit fly (medfly) is the most important pest of fruits and vegetables worldwide and it is a continuous threat to the continental United States. Methods currently used to detect and to eradicate this fruit fly need to be improved to reduce costs of eradication. Previous research by SHRS scientists found that several commercially available essential oils provide short range attraction for sterile male medflies, flies that are used in preventative release programs to prevent establishment of this pest. Therefore research was conducted to evaluate essential oil concentration to optimize attraction of male medflies and to determine the most effective essential oil. Undiluted angelica seed oil, cubeb oil and manuka oil attracted more males than dilutions of the same oils, however more males were attracted to orange oil and tea tree oil that was diluted to 100 µg/µl, and to ginger root oil that was diluted to 10 µg/µl. Although all essential oils attracted more males than untreated controls, 10% tea tree oil was the most attractive and it attracted over 50% of the males tested. The results of this study found that a test of short range attraction could be used as a quality control assessment of sterile male medflies that are used for sterile insect release by regulatory agencies. Identification of volatile chemicals responsible for this attraction may be used to improve medfly detection and control approaches.

Technical Abstract: Plant essential oils have a number of roles in insect pest management. For male Ceratitis capitata, this includes use of angelica seed oil as long range attractants and ginger root oil as aromatherapy, which is exposure to sterile males to increase mating success. Neither of these plants are hosts for C. capitata and the chemical basis for these effects is unknown. Small cage bioassays were conducted to test short range attraction of sterile males to angelica oil, ginger root oil, manuka oil, orange oil, cubeb oil, and tea tree oil. Previous research found all of these oils attracted males when undiluted oil (5 µL) was tested. Herein we compared attraction to undiluted and 100 µg/µl, 10 µg/µl, 1 µg/µl concentrations diluted with hexane to determine if concentration affected short-range attraction. Undiluted angelica seed oil, cubeb oil and manuka oil attracted more males than dilutions of the same oils, however more males were attracted to orange oil and tea tree oil that was diluted to 100 µg/µl, and to ginger root oil that was diluted to 10 µg/µl. Overall, the highest attraction of sterile males (53%) was to tea tree oil (500 µg). Additional studies are needed to determine the chemicals responsible for this attraction, but bioassays of short range attraction to tea tree oil may be useful for quality control assessment of sterile males used in the sterile insect technique for pest control.