INTERACTIONS between FORMOSAN SUBTERRANEAN TERMITES (ISOPTERA: RHINOTERMITIDAE) and WOOD DECAY FUNGI

Abstract:
This study compares the responses of termites to the lignin-degrading basidiomycete, Marasmiellus troyanus (Murrill) Singer, grown on different substrates, and examines the tunneling behavior of termites in sand treated with extracts of fungus-infected pure lignin versus solvent-treated sand. Termites showed a significant preference for lignin infected with M. troyanus versus uninfected lignin and sawdust infected with M. troyanusversus uninfected sawdust, but not cellulose infected withM. troyanusversus uninfected cellulose. When termites were presented with a choice of lignin versus sawdust, there were no significant differences in the response of termites in the tests where both substrates were uninfected or where both substrates were infected with M. troyanus. However, in choice tests where only one of the substrates was infected, there were significantly more termites in the fungus-infected substrate. The number of termites was significantly greater in tips containing extract-treated sand compared with tips containing solvent- treated sand for tests with both the pentane and methanol extracts of lignin infected with M. troyanus. These results indicate that M. troyanusproduces a chemical during the process of metabolizing lignin that elicits a positive response in termites.