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51.
Gérard?CoureaudEmail author Dominique?Langlois Guy?Perrier Benoist?Schaal 《Chemoecology》2003,13(4):187-192
Summary. In the rabbit, lactating females emit a volatile
compound in milk, the mammary pheromone (MP), that
triggers rooting for the nipple and its grasping in pups.
Previous studies have shown that the MP seems to act selectively,
in terms both of intensity and quality. Here, we aimed
to add new evidence to these properties of the MP. Newborn
rabbits (n=825) were submitted to an oral activation test
allowing to measure their searching/grasping responses
towards different stimuli. In Experiment 1 we assessed
whether pups respond to the MP in an intensity-dependent
manner. In Experiment 2 we assessed the activity of 20
volatiles previously identified in rabbit milk, other than the
MP, which were never systematically tested for intensitydependence.
The assays showed that a) neonatal responses
are released by the MP only for a limited range of concentrations;
b) the 20 other odorants from milk are inactive at
any concentration. Thus, the MP appears to be the single
volatile from rabbit milk that releases searching/grasping
behaviour in pups. 相似文献
52.
Thomas Hartmann Claudine Theuring Till Beuerle Elizabeth A. Bernays 《Chemoecology》2004,14(3-4):207-216
Summary. The alkaloid profiles of the life history stages
of the highly polyphagous arctiid Estigmene acrea were
established. As larvae individuals had free choice between
a plain diet (alkaloid-free) and a diet that was supplemented
with Crotalaria-pumila powder with a known content and
composition of pyrrolizidine alkaloids (PAs). Idiosyncratic
retronecine esters (insect PAs) accounted for approximately
half of the PAs recovered from the larvae. These alkaloids
were synthesized by the larvae through esterification of dietary
supinidine yielding the estigmines, and esterification of
retronecine yielding the creatonotines. The retronecine is
derived from insect-mediated degradation of the sequestered
pumilines (macrocyclic PAs of the monocrotaline type).
With one exception, the PA profiles established for larvae
were found almost unaltered in all life-stages as well as
larval exuviae and pupal cocoons. The exception is the
males, which in comparison to pupae and adult females,
showed a significantly decreased quantity of the creatonotines
and pumilines. These data support the idea that
the creatonotines are direct precursors of the PA-derived male
courtship pheromone, hydroxydanaidal. Crosses of PA-free
males with PA-containing females and vice versa confirmed
an efficient trans-mission of PAs from males to females and
then from females to eggs. In single cases a male bestowed
almost his total PA load to the female, and a female her total load
to the eggs. The results are discussed with respect to pheromone
formation, PA transmission between life-stages, and the
defensive role of PAs against predators and parasitoids 相似文献
53.
Foraging behavior and the mechanisms that regulate foraging activity are important components of social organization. Here
we test the hypothesis that brood pheromone modulates the sucrose response threshold of bees. Recently the honeybee proboscis
extension response to sucrose has been identified as a ”window” into a bee’s perception of sugar. The sucrose response threshold
measured in the first week of adult life, prior to foraging age, predicts forage choice. Bees with low response thresholds
are more likely to be pollen foragers and bees with high response thresholds are more likely to forage for nectar. There is
an associated genetic component to sucrose response thresholds and forage choice such that bees selected to hoard high quantities
of pollen have low response thresholds and bees selected to hoard low quantities of pollen have higher response thresholds.
The number of larvae in colonies affects the number of bees foraging for pollen. Hexane-extractable compounds from the surface
of larvae (brood pheromone) significantly increase the number of pollen foragers. We tested the hypothesis that brood pheromone
decreases the sucrose response threshold of bees, to suggest a pheromone- modulated sensory-physiological mechanism for regulating
foraging division of labor. Brood pheromone significantly decreased response thresholds as measured in the proboscis extension
response assay, a response associated with pollen foraging. A synthetic blend of honeybee brood pheromone stimulated and released
pollen foraging in foraging bioassays. Synthetic brood pheromone had dose-dependent effects on the modulation of sucrose response
thresholds. We discuss how brood pheromone may act as a releaser of pollen foraging in older bees and a primer pheromone on
the development of response thresholds and foraging ontogeny of young bees.
Received: 24 May 2000 / Revised: 26 September 2000 / Accepted: 15 October 2000 相似文献
54.
Summary. Hydroxydanaidal, the pyrrolizidine alkaloid-derived male corematal pheromone active in the close-range precopulatory interactions
of the moth Utetheisa ornatrix, appears not to contribute to the chemical defense of this moth. The compound failed to manifest feeding deterrency as an
additive to mealworms, in assays with a lycosid spider (Lycosa ceratiola). Moreover, contact with the male’s coremata, such as appears to occur inevitably in consequence of courtship in Utetheisa, does not in itself reduce the palatability of the female moth. 相似文献
55.
Justus Kristine A. Murlis John Jones Chris Cardé Ring T. 《Environmental Fluid Mechanics》2002,2(1-2):115-142
The patterns of stimulus available to moths flying along pheromone plumes in a 3-m-long wind tunnel were characterized using a high frequency photoionization detector in conjunction with an inert tracer gas. Four contrasting flow regimes and source conditions were produced: odor released in pulses from a vertical and horizontal array of four sources, odor released continuously from a point source, and odor released continuously from a point source into an oscillatory wake. Although the four flow regimes produced plumes of intermittent and fluctuating concentration, there were considerable differences in the structure of the signal presented to the sensor. Pulses of tracer gas released at 10 Hz retained most of their longitudinal and lateral separation. The plume growing in the disturbed flow (`oscillatory'), was broader in its lateral extent than the plume growing in an undisturbed flow (`continuous'), and the concentrations in the former were lower at each downstream position. The signal recorded in the disturbed flow had higher intermittency, but the ratio between the peak concentration and the signal mean was lower than in the continuous plume. Time scales were typically longer in the tunnel than in a field setting, but length scales and the main features of intermittency and fluctuation were similar. Moths flying along plumes of pheromone in this and similar wind tunnels typically slow their velocity and narrow the lateral excursions of their flight track as they approach a pheromone source. Which features of the plumes measured in this study account for these behavioral reactions remains to be determined. 相似文献
56.
Summary Males ofCarpophilus freemani Dobson (Coleoptera: Nitidulidae) produce an aggregation pheromone to which both sexes fly in a wind-tunnel bioassay. The major pheromone component (ca. 30 ng per male per day in volatile collections) was identified as (2E,4E,6E)-5-ethyl-3-methyl-2,4,6-nonatriene. A minor component, (2E,4E,6E,8E)-7-ethyl-3,5-dimethyl-2,4,6,8-undecatetraene, was 3–10% as abundant as the major triene and was 5–20% as active when compared at relative doses ranging from natural proportions to 1:1. These compounds act synergistically: a mixture of major and minor components in natural proportions attracted more than twice as many beetles as the major component alone, and the mixture fully accounted for the activity of male-derived volatile collections. Six other male-derived conjugated hydrocarbons, ranging from 2% down to 0.04% as abundant as the major component, were also identified. These are (in order of decreasing bioassay activity when compared on an equal-weight basis): (3E,5E,7E)-6-ethyl-4-methyl-3,5,7-decatriene, (2E,4E,6E)-5-ethyl-3-me-thyl-2,4,6-octatriene, (3E,5E,7E,9E)-8-ethyl-4,6-dimethyl-3, 5,7,9-dodecatetraene, (2E,4E,6E,8E)-3,5,7-trimethyl-2,4,6, 8-undecatetraene, (3E,5E,7E)-5-ethyl-7-methyl-3,5,7-undecatriene, and (2E,4E,6E)-3,5-dimethyl-2,4,6-nonatriene. All structure identifications were confirmed by synthesis. In the wind tunnel, the pheromone acted synergistically with host-type volatiles such as propyl acetate, valeric acid, and ethanol. This concept was verified by fields tests in California, in which there was dramatic synergism between the pheromone and fermenting host materials. Pheromone biosynthesis is discussed. 相似文献
57.
Summary. We adapted a four-arm olfactometer (55 × 55 × 5.5 cm) for bioassays of large insects and its usefulness was evaluated by testing
the responses of three beetles, the palm weevil Rhynchophorus palmarum (L.) (Coleoptera: Curculionidea) and two Dynast scarabs Strategus aloeus (L.) and Oryctes rhinoceros (L.) (Coleoptera: Scarabaeidae) to plant odours and aggregation pheromones. This olfactometer was coupled to a volatile delivery
system dispensing highly volatile semiochemicals at constant concentrations. We materialized airflows in the olfactometer
by discolouring sensitive papers with acid vapours under various conditions (air straighten by stainless steel grids in inputs
and output, 500 ml/min per arm) to visualize air turbulence and to test air-tightness. The volatile delivery system can be
used to mix and dispense a broad range of concentrations of semiochemicals in air from diluted aqueous solutions. It was calibrated
by measuring the release of the pheromone using solid phase-microextraction (SPME). Dose-response curves to synthetic pheromone
were obtained for O. rhinoceros of both sexes. Coupling the volatile delivery system to the fourarm olfactometer provided a system with which the responses
of R. palmarum and S. aloeus to their synthetic aggregation pheromones and to natural plant volatiles could be readily observed and studied. 相似文献
58.
Summary Chemical communication plays a very important role in the lives of many social insects. Several different types of pheromones (species-specific chemical messengers) of ants have been described, particularly those involved in recruitment, recognition, territorial and alarm behaviours. Properties of pheromones include activity in minute quantities (thus requiring sensitive methods for chemical analysis) and specificity (which can have chemotaxonomic uses). Ants produce pheromones in various exocrine glands, such as the Dufour, poison, pygidial and mandibular glands. A wide range of substances have been identified from these glands. 相似文献
59.
Regine?Gries Aurélia ?Reckziegel Herman?Bogenschütz Hans-Günter?Kontzog Christian?Schlegel Wittko?Francke Jocelyn?G.?Millar Gerhard?GriesEmail author 《Chemoecology》2004,14(2):95-100
Summary. Our objective was to identify sex pheromone
components of the oak processionary moth, Thaumetopoea
processionea (Lepidoptera: Thaumetopoeidae), whose larvae
defoliate oak, Quercus spp., forests in Eurasia and impact
human health. Coupled gas chromatographic-electroantennographic
detection (GC-EAD) and GC-mass spectrometric
(MS) analyses of pheromone gland extract of female
T. processionea revealed two consistently EAD-active compounds.
They were identified as (Z,Z)-11,13-hexadecadienyl
acetate (Z11,Z13-16:OAc) and (Z,E)-11,13,15-hexadecatrienyl
acetate (Z11,E13,15-16:OAc) by comparative GC,
GC-MS and GC-EAD analyses of insect-produced compounds
and authentic standards. In replicated field experiments
(2000, 2001) in Nordbaden, Südbaden and Sachsen-Anhalt
(Germany), Z11,Z13-16:OAc and Z11,E13,15-16:OAc in
combination, but not singly, attracted significant numbers of
male moths. It will now be intriguing to investigate whether
Z11,E13,15-16:OAc, or its corresponding alcohol or aldehyde,
serves as a pheromone component also in other species of
the Thaumetopoeidae. 相似文献
60.
Gábor Szőcs Miklós Tóth Zsolt Kárpáti Junwei Zhu Christer Löfstedt Ernst Plass Wittko Francke 《Chemoecology》2004,14(1):53-58
Summary. In order to elucidate the composition of the female sex pheromone of the
northern (beech) winter moth, Operophtera fagata
Scharf. (Lepidoptera: Geometridae), ovipositor extracts of unmated, calling females
were analysed by gas chromatography with simultaneous electroantennographic and flame
ionization detection (GC-EAD/FID). Male antennal responses indicated three active
components, two of which had distinct matching peaks in the FID trace. Using coupled
gas chromatography- mass spectrometry (GC-MS), these two compounds were identified as
(9Z)-nonadecene (9Z-19:Hy), and (6Z,9Z)-nonadecadiene (6Z9Z-19:Hy), respectively. The
third component, present in very small amounts only, was identified as (1,3Z,6Z,9Z)-nonadecatetraene
(1,3Z6Z9Z-19:Hy), known as the sex pheromone of the common winter moth,
O. brumata. Field tests revealed that traps baited with 6Z9Z-19:Hy
and 1,3Z6Z9Z-19:Hy caugth large numbers of male O. fagata.
Both compounds were found to be essential for attraction of
O. fagata. In addition,
the diene prevented captures of co-occurring O. brumata.
In contrast, 9Z-19:Hy neither influenced the attractiveness of the two-component mixture
towards O. fagata nor contributed to bait specificity.
A binary mixture of 6Z9Z-19:Hy and 1,3Z6Z9Z-19:Hy in a ratio of 10:1, applied to pieces
of rubber tubing, constituted a highly attractive and species-specific bait for
O. fagata, which can be used for monitoring of the
flight of this defoliator pest of deciduous forests. 相似文献