Electrophysiology and Behavioural Feedback of Diamondback moth,Plutella xylostella(L.) (Lep., Plutellidae) to Volatiles from a non-Host Plant,Lantana camaraL. (Verbenaceae var.aculeate)

Abstract

Electroantennograms (EAGs) were recorded from laboratory-reared male and female Plutella xylostella (Lepidoptera: Plutellidae) adults in response to the essential oil and its selected components belonging to oxy-and hydrocarbon monoterpenoids as well as a sesquiterpenoid from the non-host plant, Lantana camara L. (Verbenaceae var. aculeate). Measurable EAG responses were elicited to all compounds tested; and, mean, pooled EAGs to the sesquiterpene were larger in magnitude than those in response to oxy- and hydrocarbon monoterpenoids. Females were found to be more responsive than males. However, their responses to hydrocarbon monoterpenoids are smaller than those of male moths. Subsequent behavioural analyses in a four-armed olfactometer revealed R-(+)-limonene and (-) germacrene-D to be attractive to female moths. In laboratory cages, these two volatiles also stimulated oviposition and had little repulsive effect on third instar-larvae of the test insect.