Cuticular hydrocarbons in queens, workers and drones of the Indian honeybee Apis cerana indica (Fab.)

Abstract

Cuticular hydrocarbons (CHCs) have evolved as a communication cues and they play a significant role in the life of social insect. Although the primary function is to prevent desiccation, CHCs are also used in recognition of individuals and insect gregariousness. In this paper we examined the CHCs composition of queens, workers and drones of Apis cerana indica. CHCs analysis by Gas Chromatography-Mass Spectrometry revealed 45 different molecules. In drones, 21-37 carbon chain length hydrocarbons comprising of a complex mixture of alkanes, alkenes, mono-, di-, tri-methyl alkanes and alkadienes were detected. Alkanes of drones resemble those found in workers except pentacosane and triacontane which was not detected in the latter. Workers showed pentacosane, heptacosane, 11-Methyl-heptacosane, 13-Methyl-heptacosane, nonacosane, nonacosene, 13-Methyl-nonacosane and 15-Methylnonacosane as major CHCs. Workers had an equal number of straight alkanes and alkenes but differing in their proportions and also containing fewer branched hydrocarbons with chain lengths ranging from 21-37 carbons. Further, workers had significantly higher concentration of nonacosene, pentatriacontene, heptatriacontene as compared to drones. In queens much simpler and straight chain hydrocarbons with carbon chain ranging from 21-37 were detected. Several branched hydrocarbons as compared to drones and workers were absent. Queens had a higher concentration of alkanes than workers and drones.