Insect pests of the Herbarium of the Palermo botanical garden and evaluation of semiochemicals for the control of the key pest Lasioderma serricorne F. (Coleoptera: Anobiidae)

Abstract

The herbaria are scientific tools of great importance that preserve extinct, rare, endemic, and common plant species and also have importance as Cultural Heritage for their historical and esthetical value. Herbaria can be infested by several insect pests feeding on dried plants, and their management is often complicated and difficult as the use of chemical insecticides can have negative drawbacks. This suggests a strong need for alternative control tools such as the use of semiochemicals to develop Integrated Pest Management (IPM) programs. In order to identify the main insect pests that determine the damages on the exsiccata stored in the Palermo Botanical Garden's Herbarium, one of the largest in the world, a survey of the botanical samples and their infestations was carried out. The survey pointed out that Lasioderma serricorne was the key pest of the herbarium. Consequently, experiments were conducted to evaluate and optimize the use of semiochemicals for monitoring and mass trapping L. serricorne. Two sex pheromone dispensers (polyethylene tubes and patch dispensers, made by tissue-not tissue glued with pheromone) were evaluated for their efficacy in terms of emission and insect attraction. A food attractant, Capsicum annuum dried fruit powder, was also evaluated as synergist of the pheromone. Results indicated that polyethylene tubes determined a pheromone emission more constant with time and attracted a higher number of insects in traps in comparison with patch dispensers. Moreover, the use of C. annuum fruit powder in the pheromone traps determined a significant increase of catches compared with the traps loaded with pheromone alone, suggesting the possibility that accumulation or synergist effects occur.