Enantiomeric composition of ipsdienol: A chemotaxonomic character for north American populations ofIps spp. in thepini subgeneric group (coleoptera: Scolytidae)

Abstract

Thirty-five populations ofIps pini (Say) and one population each ofIps avulsus (Eichhoff) andIps bonanseai (Hopkins) were analyzed for the enantiomeric composition of ipsdienol (2-methyl-6-methylene-2,7-octadien-4-ol). Populations ofI. pini occur as at least two distinct regional pheromone variants: New York type [32%-(-) to 56%-(-)-ipsdienol] and California type [94%-(-) to 98%-(-)-ipsdienol]. A third phenotype may occur in southeastern British Columbia, Idaho, and Montana [91%-(-) to 95%-(-)], possibly indicating a zone of hybridization. Populations of the New York type occur in southwestern British Columbia, Alberta, Saskatchewan, Minnesota, and Wisconsin suggesting a continuum through the Canadian provinces and Lake States. The presence of the New York type in western Canada is likely linked to the Quaternary history of the transcontinentally distributed host,Pinus banksiana Lamb. MaleI. avulsus [∼25%-(-)] and maleI. bonanseai [-29%-(-)] both produce ipsdienol, but not ipsenol. Production of ipsdienol by maleI. pini was evaluated in six differentPinus spp. hosts. Following transfer of maleI. pini to hosts other than the host of origin, the percentage of the (-)-enantiomer of ipsdienol declined when compared to production in the host of origin.

Application of Semiochemicals to Assess the Biodiversity of Subcortical Insects following an Ecosystem Disturbance in a Sub-boreal Forest

“…The responses of I. pini to the enantiomers of ipsdienol have been reported from other North American locations (Raffa and Klepzig 1989;Herms et al 1991). In northern Minnesota, (+/−)-ipsdienol along with lanierone would be an effective pheromone to monitor the populations of I. pini (Teale et al 1991;Seybold et al 1992Seybold et al , 1995Miller et al 1997).…”

“…As expected, I. pini was caught in greater numbers in the I. pini-pheromone-baited traps, especially in the year 2002. There is geographic variation in the production and response of populations of I. pini to various enantiomeric blends of ipsdienol (Lanier et al 1980;Birch et al 1980;Seybold et al 1995). In western populations, I. pini is attracted to 97% (−)-ipsdienol and is inhibited by (+)-ipsdienol (Birch et al 1980).…”

Pityogenes chalcographus (Coleoptera, Scolytinae) at the southernmost borderline of Norway spruce (Picea abies) in Greece

“…In P. chalcographus, methyl (E,Z)-2,4-decadienoate synergized chalcogran and increased its attractivity 35 times in a field bioassay, while methyl decadienoate alone was unattractive (Byers et al 1990). Communication via pheromones exhibits such high specificity that even slight changes in the ratio of enantiomeres have been associated with intraspecific differentiation (Lanier et al 1972, Birch et al 1980, Seybold et al 1995.…”

Incomplete barriers to mitochondrial gene flow between pheromone races of the North American pine engraver,Ips pini(Say) (Coleoptera, Scolytidae)

“…To do this, we assessed mitochondrial variation via phylogenetic analysis of individuals among populations that were previously determined to vary in aggregation pheromone production (Seybold et al 1995).…”