Bark Beetles, Pityogenes bidentatus, Orienting to Aggregation Pheromone Avoid Conifer Monoterpene Odors When Flying but Not When Walking

Table 2

Percent of walking Pityogenes bidentatus females and males responding in a laboratory olfactometer (7 June 1999) to conifer monoterpenes and aggregation pheromone components (G1 = grandisol, cV = (S)-cis-verbenol).

Chemicals^a	Percent responding^b	95% B. C. L.^c	N
Females
B = G1+ cV at 10^-9 g/μL	68.3a	55.8–78.7	60
B + monoterpenes^d at 10^-5 g/μL	65.0a	52.4–75.8	60
B + monoterpenes neat^e	70.0a	57.5–80.1	60
B + (−)-α-pinene neat^e	75.0a	62.8–84.2	60
Males
B	65.0a	52.4–75.8	60
B + (−)-α-pinene neat^e	71.7a	59.2–81.5	60

^aChemicals dispensed by evaporation from 5 μL micropipette at indicated concentration each/μL diethyl ether (release rate approximately 2.2 × concentration/min except when neat).
^bPercentages followed by same letter were not significantly different (𝛼=0.05, chi-square).
^cBinomial confidence limits for proportions.
^dMajor host Scotch pine monoterpenes: (+)-α-pinene, (−)-α-pinene, (+)-3-carene, and terpinolene were each at indicated concentration as dispensed in diethyl ether solution.
^eChemicals were dispensed neat from 5 μL micropipettes; (−)-𝛼-pinene, (+)-3-carene, and terpinolene were each released at 28, 9.4, and 4.8 μg/min, respectively, according to capillary measurements over time in the olfactometer.