RESUMO
The copulatory behavior of the male whitemarked tussock moth,Orgyia leucostigma, was released by extracts of female body scales applied to rubber septum models baited with a female sex pheromone gland. The major compounds in the scale extracts were identified by GC-MS as a series ofn-alkanes from C-21 to C-29. Of these,n-tricosane,n-tetracosane,n-pentacosane, andn-heptacosane, applied at 10 ng/septum, caused significantly more males to attempt copulation than hexane-treated controls. Mixtures of then-alkanes, resembling the composition in the scale extracts, were no better than the two most active alkanes,n-tetracosane andn-pentacosane, alone. The releaser effect of then-alkanes was dose dependent. EAG responses to the identifiedn-alkanes were small suggesting, along with the behavioral observations, that their perception occurred at very close range. Other factors releasing male copulatory behavior are discussed.
RESUMO
A rapid and sensitive procedure for measuring the release rate of aldehyde pheromones from insect lures has been developed. Using cold traps to condense aldehydes released into an airstream, the amount of pheromone in the aqueous condensate could be directly analyzed using a luminescence assay based on the response of bacterial luciferase to long chain aldehydes. A high recovery (approximately 70%) of aldehyde pheromone in the cold trap was obtained even when amounts as low as 10 ng were released into the airstream. Trapping times as low as 5 min can be used and analysis requires only a few seconds after temperature equilibration of the sample. This approach was applied to measure the release rate of 11-tetradecenal from different spruce budworm lures as well as to demonstrate that the release of aldehyde from a lure containing [14C]-cis-9-hexadecenal correlated closely to the release rate of radioactive material.
Assuntos
Aldeídos/análise , Feromônios/análise , Animais , Temperatura Baixa , Luciferases/metabolismo , Medições Luminescentes , Controle Biológico de Vetores , Vibrio/enzimologiaRESUMO
SCOT capillary Chromatographic and SCOT capillary chromatographic-mass spectrometic analyses of gland washes and effluvia of virgin femaleChoristoneura occidentalis Free, have been conducted with both a diapausing and nondiapausing strain of this insect. The following compounds were identified in gland washes and effluvia in both strains:E andZ11-14â¶Ald,E andZ11-14â¶Ac,E andZ11-14â¶OH and 14â¶Ald, 14â¶Ac, and 14â¶OH. The average aldehyde: acetate: alcohol ratio found by analysis of single glands by virgin females (nondiapausing strain) was 1â¶7â¶0.73. Analysis of virgin female effluvia gave this ratio as 10â¶3â¶8 (diapausing strain: %Z=8, 11, 15, respectively) and 10â¶3â¶6 (nondiapausing strain: %Z=8, 11, 12, respectively). The saturated components were generally 1-2% of theE isomer in each case. Comparisons of EAG responses of bothC. occidentalis andC. fumiferana toE11-14â¶Ald,E11-14â¶Ac andE11-14â¶OH were made. Correlations with both laboratory and field data previously published were also made betweenC. fumiferana andC. occidentalis.
RESUMO
A rapid, quantitative assay for long-chain aldehydes based on bacterial luminescence was developed. Significant luminescent responses were obtained with both saturated and unsaturated aldehydes of 12-18 carbons. Maximum responses were obtained with the 14- and 16-carbon compounds, including those that are known insect sex pheromones. The bioluminescent response was linearly related to the amount of aldehyde over a 10(4)-10(5) concentration range with as little as 0.1 pmol (â¼20 pg) of aldehyde being detected. The bioluminescent assay represents a new quantitative tool for rapidly measuring aldehyde pheromones of insects.
RESUMO
Pheromone levels in the glands of individual female moths of the spruce budworm (Choristoneura fumiferana), the western spruce budworm (C. occidentalis), the navel orangeworm (Amyelois transitella), and the corn earworm (Heliothis zea) were quantitively measured by means of a new bacterial bioluminescence assay specific for aldehydes. The sensitivity and rapidity of the bioluminescent assay enabled studies to be conducted on the dependence of the pheromone levels in the spruce budworm on age and the effect of photoperiod on the pheromone levels in the corn earworm. The bioluminescence assay provides a rapid and sensitive approach for studying aldehyde pheromone levels and their regulation in insects.
RESUMO
A newly developed bioluminescent assay was used to measure quantitatively the amount of (E)-11-tetradecenal, the major component of the sex pheromone of the spruce budworm, trapped on Porapak Q(®). The bioluminescent response was linearly related to the amount of aldehyde either deposited on the absorbent or trapped from an airstream. However, the recovery of pheromone from Porapak was dependent on whether the air was prefiltered (through Porapak) or taken directly from the atmosphere. Furthermore, pheromone on Porapak was lost with time during the flow of air through the absorbent, indicating that trapping of aldehyde pheromone should be conducted for short periods of time for optimal recoveries. The applicability of the assay system for the rapid and direct measurement of the release rates of aldehyde pheromone lures was demonstrated for pheromone lures used for baiting spruce budworm traps.
RESUMO
Air which had been drawn over virgin female Choristoneura fumiferana was passed through "Porapak Q", in this way an extract containing all the volatile compounds emitted by the insect may be obtained. (E)-11-tetradecenal but not (E)-11-tetradecen-1-ol was identified among the components of the extract. The latter compound, an inhibitor of the aldehyde, has previously been shown to be present in the secretory gland of the insect.
