A rapid analytical procedure for the determination of the position of double bonds in mixtures of monounsaturated fatty acid methyl esters has been developed. The method is based on direct capillary GC-MS-EI analysis of dimethyl disulfide adducts. The procedure was applied to mixtures of monounsaturated fatty esters from pheromone gland extracts of three tortricids from theChoristoneura genus,C. fumiferana, C. occidentalis, andC. pinus pinus, and one noctuid from the Plusiinae subfamily,Plusia chalcites. A correlation was found between the known major pheromone components in the four species with the corresponding fatty acids. Some of the additional fatty acids may be precursors to as yet unidentified minor pheromone components, present in extremely small quantities, in these species.

Analysis by gas chromatography/mass spectrometry (GC/MS) of volatiles from virgin female emerald ash borer, Agrilus planipennis Fairmaire confirmed the emission of (3Z)-lactone [(3Z)-dodecen-12-olide] but not its geometric isomer, (3E)-lactone [(3E)-dodecen-12-olide]. Gas chromatographic/electroantennographic (GC/EAD) analysis of synthetic (3Z)-lactone, which contained 10% (3E)-lactone, showed a strong response of male and female antennae to both isomers. EAG analysis with 0.01- to 100-μg dosages showed a positive dose response, with females giving significantly higher responses than males. In field experiments with sticky purple prism traps, neither lactone isomer affected catches when combined with ash foliar or cortical volatiles (green leaf volatiles or Phoebe oil, respectively). However, on green prism traps, the (3Z)-lactone significantly increased capture of male A. planipennis when traps were deployed in the canopy. Captures of males on traps with both (3E)-lactone and (3Z)-hexenol or with (3Z)-lactone and (3Z)-hexenol were increased by 45-100%, respectively, compared with traps baited with just (3Z)-hexenol. In olfactometer bioassays, males were significantly attracted to (3E)-lactone, but not the (3Z)-lactone or a 60:40 (3E):(3Z) blend. The combination of either (3E)- or (3Z)-lactone with Phoebe oil was not significantly attractive to males. Males were highly attracted to (3Z)-hexenol and the (3Z)-lactone + (3Z)-hexenol combination, providing support for the field trapping results. These data are the first to demonstrate increased attraction with a combination of a pheromone and a green leaf volatile in a Buprestid species.

(E)-6,10-dimethyl-5,9-undecadien-2-ol (geranyl acetol), termed here fuscol, was identified as a male-produced pheromone emitted by Tetropium fuscum (F.) and Tetropium cinnamopterum Kirby. In field experiments, traps baited with synthetic fuscol alone were not significantly attractive, but the combination of fuscol plus host volatiles (a synthetic blend of monoterpenes plus ethanol) attracted significantly more male and female T. fuscum and female T. cinnamopterum than did host volatiles alone. This is the first homoterpenoid alcohol to be described in the Cerambycidae, and the first pheromone reported from the sub-family Spondylidinae.