Efficacy of plant essential oils for repelling against American cockroach adults (Periplaneta americana L.)

Abstract

The combination of four plant essential oils (EOs) from star anise, citronella grass, lemon grass, and cinnamon was evaluated for repelling American cockroaches by the dual-choice method. A combination of star anise + citronella grass had a repellency rate of 95%. In contrast, combinations of star anise + lemon grass and star anise + cinnamon were effective between 73% and 69%, but the synthetic chemical repellent (12% DEET) was less effective at 59%. Therefore, the essential oils formulae had a high potential for effective use and, further, are harmless for healthiness and the environment. Thus, they can replace more toxic synthetic insecticides.