Repellency effects of essential oils of Cymbopogon winterianus, Eucalyptus globulus, Citrus hystrix and their major constituents against adult German cockroach (Blattella germanica Linnaeus (Blattaria: Blattellidae)

Abstract

© 2019 Jordan Journal of Biological Sciences. The German cockroach, Blattella germanica, has been considered a major source of allergens and pathogens. The application of repellents has received attention to keep these insects away from their hiding places such as kitchen cupboards. In this study, the repellent potency of essential oils (EOs) and the major components of Cymbopogon winterianus, Eucalyptus globulus and Citrus hystrix against adult German cockroach were assessed. The chemical compositions of EOs were investigated using the Gas chromatography-Mass spectrometry. The results demonstrated that all investigated EOs and their active monoterpenes including 1,8-cineol, citronellal, citronellol, geraniol, limonene and linalyl acetate, exhibited repellency effects against the insect. As a result, pure monoterpenes can also be considered as alternative repellents, as the standardization of the products is easier to perform. For further studies, active monoterpenes or combinations of EOs will be developed as products and their efficacy will be compared with commonly used insect repellents.