Development of natural waxes dispensers for pheromones and use in mating disruption of the ambrosia beetle Megaplatypus mutatus in poplar (Populus spp) plantations

Abstract

Megaplatypus mutatus (= Platypus mutatus) (Chapuis) is an ambrosia beetle native to South America that attacks live trees, mining deeply into the xylem through large tunnels. This activity weakens the structural integrity of the tree, causing severe stem-breakage and mortality. Attacks are initiated by pioneer males that select a host tree and build short nuptial galleries, to which they attract females using a sexual pheromone. Previously, we showed the potential for the strategy of pheromone-mediated mating disruption of M. mutatus in commercial poplar and hazelnut plantations in South America and Europe using polyethylene reservoir dispensers for pheromones. In the present work we replaced the polymeric reservoir dispensers by monolithic dispensers made by dispersion of the pheromone in natural waxes and the addition of kaolin and we found that: prior to pheromone deployment, the mean number of galleries per tree did not differ significantly between the control and treated plots and the same was observed after the mating disruption treatment for the control plot but not for treated plots, where the mean number of galleries were reduced. These findings confirm that mating disruption is a viable tool for management of M. mutatus in poplar plantations. Using natural wax dispensers has obvious advantages from an environmental point of view.