Abstract
The chemicals emitted from the sex pheromone gland of individual Heliothis subflexa
females were sampled using a short section of thick-film megabore fused silica capillary column,
and the pheromone glands of the same females were extracted after the effluvia collection.
Both samples were treated with a silylation reagent, and then subjected to gas
chromatography-chemical ionization-mass spectrometry for quantitative and qualitative
analysis of all components. The total amount of all 11 components emitted from the glands
of calling females was 153 ng/female/hr, which was substantially higher than previously
reported. The ratios of the pheromone components in the volatile emissions and pheromone
gland extracts were generally similar to previous studies, but with notable differences. The
collections of volatiles and gland extractions contained, respectively: Z9-14:Ald (1.57%,
1.35%), 14:Ald (3.78%, 1.51%), Z7 + Z9-16:Ald (9.60%, 3.59%), Z11-16:Ald (76.14%,
18.94%), 16:Ald (2.95%, 2.17%), Z9-16:OH (0.07%, 7.21%), Z11-16:OH (1.11%, 49.04%),
Z7-16:OAc (0.48%, 1.73%), Z9-16:OAc (1.32%, 4.02%), and Z11-16:OAc (2.98%,
10.43%). The thick-film megabore column is an efficient approach for sampling the headspace for semiochemicals.
