Free fatty acids in some tissue of parasitized bug, Leptocoris augur Fabr., a pest of Kusum tree, Schleichera oleosa Lour.

Leptocoris augur is a pest of kusum plant (Schleichera oleosa), which in turn is a host of lac insect. The bug is parasitized by a mermithid nematode, Hexamermis vishwakarma, which naturally checks rapid built-up of bug population. In the present studies free fatty acids content in different tissue such as gonads (i.e., testes and ovaries), muscles and haemolymph of parasitized bugs, L. augur have been studied. H. vishwakarma not only utilize fat body proteins but also the lipid content of the fat as a result of which fat bodies disappears from the haemolymph of L. augur. The fatty acid composition of the host haemolymph is not significantly changed by H. vishwakarma parasitism in L. augur of both the sexes. H. vishwakarma Dhiman takes nutrition from the haemolymph and muscles of insect body cavity Dhiman and Singh [3]. Availability of free fatty acids in the haemolymph of host bug help the parasitoid to establish in the haemocoel. After establishment, the parasitoid induces changes in the availability of biochemicals and composition of haemolymph, by the secretion of enzymes. The parasitoid’s enzymes cause degeneration or dissolution of muscles, adipose tissues, testes as well as ovaries and the material of these organs is made available to the parasitoid. Hence, parasitoid grows at the expense of host tissues. Keywords: Leptocoris augur, Hexamermis vishwakarma, Haemolymph, Free fatty acids, Parasitoid