Vol. 3, Issue 3 (2018)
Repellency and toxicity of Citrullus colocynthis and Commiphora myrrha essential oils against Periplaneta americana populations collected from four localities in Egypt
Author(s): Rabab M Abdel-Gawad
Abstract: Periplaneta americana L. is an insect of medical important found within the human houses and hospitals that cause serious health problems. Experiments were carried in the laboratory to evaluate contact toxicity and repellent activity of essential oils (Eos) of Citrullus colocynthis (colocynthis oil) and Commiphora myrrha (myrrh oil) against laboratory strain (Lab) of P. americana and four populations collected from Cairo, Giza, Qalyubia and Beni suef in Egypt. Toxicity experiments by topical application methods revealed that myrrh oil proved to be more effective followed by colocynthis oil. However, there were no significant differences in the tested populations regarding colocynthis and marrh oils toxicity as the confidence intervals for the LD50 overlapped. Resistance ratio was very small of all populations against myrrh oil and colocynthis oil. Repellent activity of colocynthis oil and myrrh oil against adult cockroaches were determined by area preference method after 24, 48 and 72 hr of exposure. The essential oils of colocynthis oil and myrrh oil acted as a repellent against the Lab, Giza, and Qalyubia populations of P. americana adults at 24h, 48 and 72 h after insect exposure. Colocynthis oil showed moderate repellent activity against the tested populations at all assessment times. In addition, myrrh oil had the strongest repellency of P. americana collected from Beni suef with mean percentage of repellency (90%) after 72 h post treatment. It is concluded that myrrh oil and colocynthis oil exhibits both insecticidal and repellent activity against P. americana and can potentially be used to management cockroaches in different localities in Egypt.