METABOLISM OF 1,8-CINEOLE IN TEA TREE (MELALEUCA-ALTERNIFOLIA AND MELALEUCA-LINARIIFOLIA) BY PYRGO BEETLE (PAROPSISTERNA-TIGRINA)

The frass of the pyrgo beetle (Paropsisterna tigrina) feeding on comme rcial plantations of the terpinen-4-ol chemical variety of the Austral ian tea tree, Melaleuca alternifolia, was found to contain a volatile oil almost identical to the essential oil of the ingested leaf. When b eetles were fed leaf containing substantial quantities of 1,8-cineole, the predominant frass metabolite as determined by MS, IR, C-13 and H- 1 NMR, GC, and CoGC was (+)-2beta-hydroxycineole. Both male and female adults and larvae metabolized Melaleuca oils in similar ways.