Once upon a time, when I was a chemist.
Behavioral Activity of Catnip (Lamiaceae) Essential Oil Components to the German Cockroach (Blattodea: Blattellidae) Chris J. Peterson,d Leah T. Nemetz,a, d Leah M. Jones,b, d and Joel R. Coatsc, d
aUniversity of Wisconsin–Stephens Point, Stephens Point, WI 54481 bMillikin University, Decatur, IL 62522 cTo whom correspondence should be addressed. dPesticide Toxicology Laboratory, Department of Entomology, Iowa State University, Ames, IA 50011
Manuscript Received by the Society 19 March 2001 Manuscript Accepted 22 August 2001
The essential oil of catnip, Nepeta cataria L., contains two isomers of nepetalactone, E,Z– and Z,E-nepetalactone, and was tested for repellent activity to adult male German cockroaches, Blattella germanica (L.), in a choice-test arena. The two isomers of nepetalactone were purified by using preparative thin-layer chromatography and tested for behavioral activity in the choice-test arena. Significant differences due to concentration were detected by analysis of variance, and the responses were compared by least-squared means analysis. The activities of the essential oil and purified isomers were compared with N,N-diethyl-3-methylbenzamide (DEET) by a paired t-test. E,Z-Nepetalactone was the most active of the compounds tested, being significantly more active to this species than equivalent doses of DEET, the essential oil, or Z,E-nepetalactone. Antennectomized insects showed no response to concentrations that were active against intact insects.