排序方式: 共有96条查询结果,搜索用时 15 毫秒
61.
The Russian River-Cooper Lake-Resurrection River trail system, on the Kenai Peninsula, Alaska, traverses essential brown bear
habitat. To set management guidelines for this area, the trail system was monitored using questionnaire cards and electronic
trail counters from 1984 through 1987. This helped to determine the extent and type of human use and human-bear encounters
in the area. Management recommendations were intended to reduce the potential displacement of brown bears by hikers and to
inform wilderness users of the proper camping techniques to avoid attracting bears to the campsite. An average of 5800 visitors
hiked or camped along the trail system each year. Encounters between hikers and brown bears averaged 7/yr while encounters
with black bears averaged 35/yr. Minor problems occurred with both the electronic trail counters and the questionnaire. Modilications
to these methods are discussed. A Limits of Acceptable Change format should be considered for the trail system to determine
the character and future direction of recreational activities and monitoring of the trail system should continue in the future. 相似文献
62.
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
63.
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
64.
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
65.
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
66.
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
67.
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
68.
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
69.
Summary. The bolas spider, Mastophora hutchinsoni, attracts Lacinipolia renigera and Tetanolita mynesalis males by mimicking the female moth sex pheromones. However, as the prey species use completely different pheromone blends
we conducted experiments to determine how this is accomplished by the predator. The periodicity of L. renigera mate-seeking activities occurs early in the scotophase, whereas male T. mynesalis are active late at night, corresponding with periods when these moths are captured by the spider. The pheromone blend of
early-flying L. renigera interferes with attraction of late-flying T. mynesalis to its pheromone in a dose-dependent manner, suggesting the spider must always produce a single sub-optimal “compromise”
blend for both species or that it adjusts its allomonal blend to optimize capture of the respective prey species at different
times during the night. We delayed (L. renigera) or advanced (T. mynesalis) the periodicity of male activity through photoperiodic manipulation and found that the bolas spider attracted both prey
species outside their normal activity windows. These results support the idea that bolas spiders produce components of both
species at all times rather than producing the pheromone of each prey species at different times of the night. However, using
coupled gas chromatography-electroantennography, we also demonstrated that the spider decreases its emission of the L. renigera pheromone over the course of the night. This modification should reduce the behavioral antagonism of the L. renigera pheromone on T. mynesalis males and increase the predator's success of attracting T. mynesalis during this prey's normal activity window late at night.
Received 13 October 2001; accepted 28 December 2001. 相似文献
70.
Summary By means of gas chromatography, gas chromatographic coupled mass spectrometry, trail-following experiments and electrophysiological recordings from worker antennae, the major trail pheromone components from the hindgut of the formicine speciesCamponotus atriceps andC. floridanus were identified as 3,5-dimethyl-6-(1-methylpropyl)-tetrahydropyran-2-one and nerolic acid, respectively. The Dufour's gland contents of both species, investigated by gas chromatographic coupled mass spectrometry, show significant differences.Pheromones 104: Janssen E, Übler E, Bauriegel L, Kern F, Bestmann H-J, Attygalle AB, Steghaus-Kovacs S, Maschwitz U: Trail pheromone of the Ponerinae antLeptogenys peuqueti (Hymenoptera: Formicidae): a multicomponent mixture of related compounds 相似文献