EFFECT OF EXPOSURE OF EGGS TO VAPORS FROM ESSENTIAL OILS ON EGG MORTALITY, DEVELOPMENT AND ADULT EMERGENCE IN EARIAS-VITTELLA (F) (LEPIDOPTERA, NOCTUIDAE)

Exposure of freshly laid eggs of Earias vittella (F.) to volatiles fro m the essential oils of Japanese mint (Mentha arvensis L.), peppermint (M. Piperita L.), palmarosa (Cymbopogon martini (Roxb.) Wats) and cit ronella (C. winterianus Jowitt) for more than 24 h inhibited hatchabil ity to varying degrees. This was. however, significant only in respect of the citronella and palmarosa oil vapour treatments when compared w ith the control. Less than 50% of larvae from eggs exposed to peppermi nt or citronella oil volatiles became adults. Male and female pupal we ights of larvae that survived embryonic exposure to the volatiles of a ll the four essential oils were significantly lower than that of the u ntreated. The implications of these findings are discussed in relation to the possible role of the principal chemical constituents of these essential oils in regulating egg hatchability and developmental events in the biology of E. vittella.