Five doses of lanierone (2-hydroxy-4,4,6-trimethyl-2,5-cyclohexadien-1-one) were tested with one dose of enantiomerically pure [99.4% (4R)-(-)] ipsdienol (2-methyl-6-methylene-2,7-octadien-4-ol) for activity as an aggregation pheromone ofIps pini (Say) in California. The response ofI. pini to 1 mg/day ipsdienol + 20 μg/day lanierone was significantly greater than the response to ipsdienol alone, but the response pattern did not demonstrate a clear dose-response relationship. The response to the highest dose of lanierone (2 mg/day) was significantly lower than the response to ipsdienol alone. Ipsdienol attracted significantly moreI. pini than a male-infested log. Lanierone did not alter the percentage of maleI. pini responding to ipsdienol alone. Neither sex ofI. pini orDendroctonus brevicomis LeConte from California produced detectable amounts of lanierone, but myrcene-aerated maleD. brevicomis produced 97.8%-(4S)-(+)-ipsdienol. The black-bellied clerid,Enoclerus lecontei (Wolcott) (Coleoptera: Cleridae) was attracted to lanierone when released with ipsdienol. Neither compound was attractive when released alone, proving synergism for the kairomone of this predator. Lanierone did not influence the response of the predatorsTemnochila chlorodia (Mannerheim) (Coleoptera: Trogositidae) andEnoclerus sphegeus (F.) (Coleoptera: Cleridae), which were attracted to all treatments containing ipsdienol.Tomicobia tibialis Ashmead (Hymenoptera: Pteromalidae) responded in significantly greater numbers to the male-infested log than it did to ipsdienol or ipsdienol + 20 μg/day lanierone.

Abstract-Lanierone strongly synergized the attraction of male and female Ips pini (Say) to ipsdienol in New York and Wisconsin. Synergy was only weakly significant in Montana and British Columbia and not significant in California. Catches of I. pini in ipsdienol-baited traps were increased 0% (i.e., nonsignificant) to 9942% by lanierone, with the highest increases in eastern North America. Lanierone had the least effect in California. The effects of lanierone on sex ratios of I. pini in trap catches varied significantly between regions. The addition of lanierone to ipsdienol-baited traps resulted in a general increase in male representation at nine of 12 sites. Ips integer (Eichhoff) was attracted to lanierone alone. Ipsdienol reduced the response of /. integer to lanierone. Enoclerus lecontei (Wolcott) (Cleridae) preferred traps baited with the combination of ipsdienol and lanierone. (R)-(-)-Ipsdienol was attractive to E. sphegeus (F.), Thanasimus undatulus (Say) (Cleridae), and Temnochila chlorodia (Mannerheim) (Trogositidae), while racemic ipsdienol was attractive to E. nigrifrons var. gerhardi Wolc. and Thanasimus dubius (F.). Lanierone had no effect on these species.

The beetle Monochamus alternatus Hope (Coleoptera: Cerambycidae) is an efficient vector of pine wood nematode, the causal pathogen of pine wilt disease, that has resulted in devastating losses of pines in much of Asia. We assessed the response of adult M. alternatus to 2-(undecyloxy)-ethanol, the male-produced pheromone of the congeneric M. galloprovincialis Dejean, in field experiments in Fujian Province, People's Republic of China. Both sexes of M. alternatus were attracted to lures consisting of 2-(undecyloxy)-ethanol combined with the host plant volatiles alpha-pinene and ethanol. A follow-up experiment showed that 2-(undecyloxy)-ethanol was synergized by both ethanol and alpha-pinene. Coupled gas-chromatography mass-spectrometry analyses of volatiles sampled from field-collected beetles of both sexes revealed that 2-(undecyloxy)-ethanol was a sex-specific pheromone component produced only by males. The combination of 2- (undecyloxy) -ethanol with ethanol and/or alpha-pinene will provide a valuable and badly needed tool for quarantine detection, monitoring, and management of M. alternatus.