REPELLENT PROPERTIES OF THE HOST COMPOUND 4-ALLYLANISOLE TO THE SOUTHERN PINE-BEETLE

The phenylpropanoid 4-allylanisole is a compound produced by loblolly pines (Pinus taeda L.), an abundant species in southern pine forests and a preferred host of southern pine beetle (Dendroctonus frontalis Zimmermann). Repellency of individual beetles was demonstrated in laboratory behavioral assays of D. frontalis and other scolytids. Inhibition was demonstrated in natural populations of D. frontalis using baited traps. In both tests, response to the inhibitory pheromone verbenone was used for comparison. In the laboratory, a higher proportion of newly emerged and reemerged D. frontalis responded negatively to 4-allylanisole than to verbenone. However, fewer reemergent than newly emerged individuals responded to either compound. In all field trials, the response of D. frontalis to its attractant pheromone in funnel traps was significantly reduced by simultaneous release of 4-allylanisole. In most trials total reduction did not differ from verbenone; however, unlike verbenone, 4-allylanisole reduced male and female catches proportionally. Both compounds together did not significantly further reduce trap catch. The response of a major predator, Thanasimus dubius (F.), to the attractant pheromone of D. frontalis, did not differ with the simultaneous release of either verbenone or 4-allylanisole. The results of preliminary field applications are presented and discussed.