Abstract

DETERMINATION OF N-ALKANE CONSTITUENTS IN THE EPICUTICULAR WAX OF LEAVES AND YOUNG PODS OF CASSIA ALATA OFTEN INFESTED BY LARVAE OF CATOPSILIA PYRANTHE.

Dr. Irani Biswas*, Prof. Subrata Laskar, Prof. Ambarish Mukherjee

Abstract

The present communication is a first time investigation on the n-alkane compositions of the epicuticular wax of leaves and young pods of Cassia alata, a leguminous medicinal plant often attacked by the larvae of the butterfly Catopsilia pyranthe (mottled emigrant butterfly) which voraciously feed upon the leaves and young pods of this plant during its flowering and fruiting time. The normal chained hydrocarbons (n-alkanes) in these plant parts ranged from C12-C27. The cumulative percentage of low volatile n-alkanes (C12-C23) showed much higher values than the medium chained n-alkanes (C24-C27) which perhaps recalls the characteristics of herbivore induced plant volatiles (HIPV). These are complex blends of different volatile organic compounds (VOC) including alkanes which are usually produced by host plants infested by herbivorous insects. The overall findings not only update the phytochemical database of surface lipid of the plant for the first time in terms of n-alkane analyses but might also provide certain cues towards host recognition of the plant in insect herbivory.

Keywords: Cassia alata, epicuticular wax, n-alkane, host recognition cues.