Phenotypic and genetic variation in the pheromone system of the bark beetle Ips pini (Coleoptera: Scolytidae)

The influence of various factors on the production of and response to ipsdienol enantiomeric blends in Ips pini was investigated using field and laboratory techniques. Funnel traps were baited with a range of ipsdienol enantiomers to compare the attraction of male and female I. pini and the parasitoid Tomicobia tibialis. Males and females responded similarly. Tomicobia tibialis was attracted to the blend most attractive to I. pini. The recovery of ipsdienol and lanierone by three collection methods (aeration, frass and hindgut extracts) was tested. Aerations recovered the greatest quantity and variety of compounds. However, the ratio of lanierone to ipsdienol was similar among methods. Selective breeding of I. pini for three lines of beetles producing extreme pheromone phenotypes was performed. A change in the phenotype of subsequent generations was induced, and means were significantly different among generations for two of three lines. The realized heritability of pheromone production was calculated.