Hydrocarbons in the surface lipids of pupal tobacco budworms, Heliothis virescens

Abstract

The surface lipids from pupae of the tobacco budworm, Heliothis virescens, had five homologous series of alkanes. Normal alkanes from 17 to 34 carbon atoms comprised 33% of the alkanes; heptacosane was the major constituent at 11%. Monomethylalkanes comprised 50% of the alkanes and consisted of terminally branched 2- and 3-methylalkanes and internally-branched components. The 9-, 11-, 13-, and 15-methylhentriacontane isomers were the major constituents at 24%. Dimethylalkanes from 33 to 35 carbon atoms comprised 14% of the alkanes. One GLC peak was tentatively identified as a mixture of 11,19- and 13,21-dimethyltritriacontane. Analyses of the hydrocarbons of four strains of pupae showed no difference in the type of hydrocarbons found in the cuticular surface lipids. However, a non-tanning body mutant of one strain did show an increase in the amount of hydrocarbon present. There was no difference in the amount of cuticular surface lipid on diapausing pupae compared with that on non-diapausing pupae. Furthermore, there was no difference in the amount of cuticular surface lipid on male pupae when compared with female pupae in both diapausing and non-diapausing stages of development.