GC-EAD

GC-EAD Gas chromatography combined with an EAG detector GC-MS Gas chromatography combined with mass spectrometry HPLC High performance liquid chromatography KI Kovats retention index... 

Since the last review [14], the female-produced sex pheromones of Diprion nipponica, Macrodiprion nemoralis, and Microdiprion pallipes have been investigated and clarification of the active components has been made. GCMS of the GC-EAD-active material in virgin female extracts of D. nipponica have suggested that the propanoate ester of (2S,3k,9S)-3,9-dimethylundecan-2-ol 2 is the sex pheromone. Field tests with synthetic material confirmed its activity,... 

Volatiles and cuticular extracts from both sexes of the currant stem girdler, Janus integer, were analyzed by GC-EAD using antenna ofboth sexes. A female specific compound, (9Z)-octadec-9-en-4-olide 7, was identified as active only on male antennas [33]. Separation by chiral GC has shown that only one enantiomer is produced in females. The synthesis ofboth enantiomers has recently been described [34] and the field testing results are forthcoming. 

In recent years, there is only one example of a pheromone in solitary Apocrita being chemically identified. Chiral GC and chiral GC-EAD provided identification of (3S)-(+)-linalool 8 >99.9% e.e. as a mandibular gland mate attractant in both males and females of Colletes cunicularius. Male contact with a scented source could be initiated with 5 ng per lure (3S)-(+)-linalool, which may act as both a sex attractant and a food attractant [35]. 

Flowers of some orchids mimic both the appearance and sex pheromone of virgin females of certain species of bees or wasps. This sexual deception results in pollination by male hymenoptera that would not normally visit flowers. Japanese honey bee drones (Apis cerana japonica) cluster on the oriental orchid (Cymbidiumpumilum) while on their mating flights [ 134]. By comparing volatile profiles of orchids and the female hymenoptera they mimic, or by GC-EAD and GC-MS analysis of orchid volatiles, several compounds have been identified that may mediate this attraction for the solitary bee Andrena nigroaenea [135, 136] and the scoliid wasp Campsoscolia ciliata [135]. 

Attractive Compounds. Pheromones of dermestid beetles were among the first ones identified from insects. Almost all have been described as one-component-systems , and re-investigations employing refined techniques, especially GC-EAD and sensitive GC-MS, may reveal the presence of additional and important compounds, which may lead to improved activity of synthetic lures, and under natural conditions may account for species specificity etc. 

Extracts of the summer chafer, Amphimallon solstitiale L. (Coleoptera Scarabaeidae), a common European scarab beetle were analyzed by GC-MS and GC-EAD. Both male and female extracts were shown to contain Acetoin — R) (5) > 9 1, as well as 2,3-butanediol — 2R, 3R) (25,35) meso =1 1 9. Although (25, 35)-butanediol did not show any activity, the other compounds elicited strong responses exclusively with male antennae. 

Pheromone gland extracts of the Australian guava moth, Coscinopty-cha improbana (Lepidoptera Carposinidae), contained four compounds that elicited responses from male moth antennae in GC-EAD analyses. These compounds, identified on the basis of GC-MS, were found to be (Z )-7-tricosene along with three monounsaturated ketones, namely (Z)-7-ocatadecen-ll-one, (Z )-7-nonadecen-l l-one and (Z )-7-tricosen-l l-one they were found in a ratio of 65 23-5 1-5 10 respectively. ... 

Coupled GC-EAD of both gland extracts and effluvial collections from female blueberry leafminer, Caloptilia porphyrectica Braun (Lepidoptera Gracillariidae), showed that females produce a single EAD-active compound. (A)-l 1 -hexadecenal was determined to be the sex pheromone based on comparison of the retention time of an authentic standard on both polar and non-polar capillary columns. Microreaction-GC-EAD analyses and field trapping results confirmed the identification. ... 

Simultaneous GC-EAD analyses of the extracts of the sex pheromone gland of the female bronzed cutworm, Nephelodes minians, indicated two compounds which eficited strong EAD responses from conspecific male antennae, (2 )-ll-hexadecenal and (2 )-ll-hexadecenyl acetate. Double bond positions were confirmed by the dimethyl disulfide derivatives of the pheromone component. In a field test, a 5 1 blend of aldehyde and ester attracted male N. minians. ... 

Three components extracted from the female glands of the large aspen tortrix, Choristoneura conflictana (Lepidoptera Tortricidae), elicited response from antennae of conspecific males using coupled GC-EAD system. The main component extracted from the glands was... 

GC-EAD analysis of the sex pheromone gland of the citrus flower moth. Prays nephelomima (Lepidoptera Yponomeutidae) revealed a single active component, (Z )-7-tetradecenal. Field trials with this monounsat-urated aldehyde in citrus orchards on the north island of New Zealand captured males successfully. ... 

Coupled GC-EAD detection analyses of pheromone gland extracts revealed one EAD active compound produced by female Lymentra lucescens and by female L. serva (Lepidoptera Lymantriidae). This compound was identified as 2-methyl-(Z )-7-octadecene by the usual analytical techniques and by comparison with an authentic synthetic compound. 

Comparative GC, GC-EAD and GC-MS analyses of extracted Setora nitens (nettle caterpillars) compounds and authentic standards showed that the candidate pheromone components were ( )-9-dodecenal and (-Z)-9,11 dodecadienal. The other two EAD-active compounds were the corresponding alcohols of these aldehydes. ... 

GC-EAD analysis of thoracic extracts of the male green lacewing, Chrysopa nigricornis Burmeister, showed that two compounds elicited response from conspecific male antennae 1-tridecene and (li , 25, 5R, 8i )-iridodial. Iri-dodial also attracted males of the goldeneyed lacewing, C oculata Say, and to a lesser extent, C. coloradensis Banks males. 

In sum, both rigorous analyses of floral odors and olfactory/behavioral assays will be required to tease apart the critical factors that underlie pollinator-flower interactions. Recent work from independent sources indicates progress in this area. For example, studies using GC-EAD and conditioned proboscis extension (Wadhams et al., 1994 Blight et al., 1997 Pham-Delegue et al., 1997) have... 

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