Dose-Dependent Pheromone Responses of Ips pini, Orthotomicus latiden (Coleoptera: Scolytidae), and associates in stands of lodgepole pine
We conducted four behavioral choice tests in stands of mature lodgepole pine in British Columbia, from 1988 to 1991, to determine the dose-dependent responses of Orthotomicus latidens (LeConte) and Ips pini (Say) to their respective pheromones. Dose-dependent responses were exhibited by I. pini to (±)-ipsdienol and lanierone, with trap catches directly proportional to pheromone release rates. We found differences in sex ration of I. pini in their resposnes to ipsdienol but not lanierone. There was no dose-dependent response exhibited by O. latidens to its pheromone. (±)-ipsenol, with or without the presence of the host kairomone, (--)-ß-phellandrene. The bark beetle predator, Enoclerus locontei (Wolcott), showed a dose-dependent response to lanierone. Thanasimus undatulus (Say) was attracted to ipsenol in a dose-dependent fashion only when traps were also baited with ß-phellandrene. Neither T. undatulus nor e. sphegeus (F.) exhibited dose-dependent responses to ipsdienol.