Behavioral and physiological response of male Callisphyris apicicornis   (Coleoptera: Cerambycidae) to virgin con-specific females’ extracts

Callisphyris apicicornis (Fairmaire & Germain) (Coleoptera: Cerambycidae: Necydalinae) is a native, xylophagous, and polyphagous longhorned beetle, currently having the status of an increasing pest in some fruit orchards in Chile which needs a control strategy. However, no efficient methods have been developed against C. apicicornis. Since pheromone- based strategies are promissory against these types of pests, it is necessary to understand the chemical communication within this species in order to collect and identify the pheromonal compounds as the first step to develop pheromone- based control tactics. The objectives of this work were to study behavioral and electrophysiological responses of males to con-specific females and its extracts, to seek out evidence of chemical communication in the intraspecific relationship of C. apicicornis. In field, we collected 112 males using 8 baited traps with alive females in two separate experiments. However, neither males nor headspace (HS) extracts were attractive for either sex in field, no males were captured in those treatments (16 traps). On the other hand, in laboratory bioassays males showed significant electroantennographic responses to females’ volatiles extracts (1.46 mV) and gland extracts (1.15 mV). Likewise, behavioral bioassay showed significant olfactometric preference for females’ volatiles and gland extracts. Our results strongly suggest a female- produced sex attractant occurs within this species, so further studies should attempt to identify and quantify the chemicals compounds with this role.

Keywords
Agricultural pest; electroantennography; insect behavior; olfactometry; sex pheromone