Showing papers in "Journal of Chemical Ecology in 1981"
TL;DR: It is concluded that polyphenols in F. vesiculosus and A. nodosum are functionally similar to terrestrial plant polyphenol (tannins) in providing chemical defenses against herbivores.
Abstract: Polyphenols from two brown algae,Fucus vesiculosus (L.) andAscophyllum nodosum (L.) Le Jolis, inhibited feeding by the herbivorous snail,Littorina littorea. The active compounds were characterized as phloroglucinol polymers with a wide molecular weight range (mol wt 300,000) by spectroscopic, Ultrafiltration, thin-layer chromatographic, and chemical degradation data. As little as 1% (dry wt) polyphenol in food reduced feeding by more than 50%, and polyphenolic extracts inhibited feeding entirely when present in concentrations of 2–5% (dry wt). Commercially available phloroglucinol dihydrate and gallotannin, which are known herbivore feeding deterrents in terrestrial plants, inhibitedL. littorea feeding when added to food media in concentrations similar to those above. We conclude that polyphenols inF. vesiculosus andA. nodosum are functionally similar to terrestrial plant polyphenols (tannins) in providing chemical defenses against herbivores. This research is the first demonstration that chemical compounds defend these two dominant, perennial marine algae from the major herbivore found in their community.
165 citations
TL;DR: Nine strains of the terrestrial bacterial genus Xenorhabdus, all isolated as symbionts of nematodes, were examined for their abilities to produce substances with antibiotic activites when grown in pure culture, and inhibition patterns indicated that different compounds were being produced by the various bacteria.
Abstract: Nine strains of the terrestrial bacterial genusXenorhabdus, all isolated as symbionts of nematodes, were examined for their abilities to produce substances with antibiotic activites when grown in pure culture. All nine produced measurable antibiotic activities against one or more of the test strains utilized. The inhibition patterns indicated that different compounds were being produced by the various bacteria. Two of the species that showed particularly strong inhibition patterns were studied in detail. The inhibitory compounds were purified and identified. Strain R produced a mixture of active substances, the major components of which were hydroxyl- and acetoxyl-bearing indole derivatives, presumably produced via tryptophan. Strain Hb, on the other hand, produced only two antibiotics, 4-ethyl- and 4-isopropyl-3,5-dihydroxy-trans-stilbenes, which are presumed to arise via polyketide pathways.
154 citations
TL;DR: Investigation of weakened hosts from a distance by bark beetles through olfaction was investigated in field experiments and showed that in these species host discrimination must occur after landing and prior to sustained feeding.
Abstract: Detection of weakened hosts from a distance by bark beetles through olfaction was investigated in field experiments. No significant numbers of Scolytidae were attracted to anaerobically treated pine bolts, stem disks, or sugar and ponderosa pine bark including phloem. Treatment of living trees with cacodylic acid induced attacks byDendroctonusbrevicomis, D. ponderosae, Ips latidens, Gnathotrichus retusus, andPityophthorus scalptor, beginning two weeks after treatment. There was no significant difference between landing rates ofD. brevicomis andD.ponderosae on screened treated trees and screened controls. There was a significant increase in landing rates ofG. retusus andI. latidens, because both species had penetrated the screen and produced pheromones. Tree frilling alone did not increase the landing rate of bark beetles. Freezing of the lower trunk with dry ice did not increase significantly the landing rate ofD. brevicomis, D. ponderosae, G. retusus, orI. latidens on screened trees, whereas unscreened frozen trees were attacked by all four species. There was no significantly higher landing rate byD. brevicomis, D. ponderosae, I.paraconfusus, I. latidens, G. retusus, orHylurgops subcostulatus on screened trees evidencing symptoms of severe infection by the root pathogenVerticicladiella wagenerii, than on symptornless trees. These experiments show thatD. brevicomis, D. ponderosae, I. paraconfusus, I.latidens, andG. retusus land, apparently indiscriminately, on healthy and stressed hosts. Thus, in these species host discrimination must occur after landing and prior to sustained feeding.
150 citations
TL;DR: Cavariella aegopodii is induced to land on traps by the monoterpene carvone, and the relevance of this to host-finding by the aphid is discussed.
Abstract: Cavariella aegopodii is induced to land on traps by the monoterpene carvone, and the relevance of this to host-finding by the aphid is discussed. Catches are reduced by linalool. The interaction of plant chemicals in natural communities is discussed, and the possibility of using repellent chemicals for crop protection is suggested.
135 citations
TL;DR: Several compounds that retard the larval growth of the tomato fruitworm,Heliothis zea (Boddie), have been isolated and identified from tomato leaves and a new caffeyl derivative of an aldaric acid (IV) is presented.
Abstract: Several compounds that retard the larval growth of the tomato fruitworm,Heliothis zea (Boddie) have been isolated and identified from tomato leaves,Lycopersicon esculentum Mill. The major allelochemics are α-tomatine (I), chlorogenic acid (II), rutin (III), and a new caffeyl derivative of an aldaric acid (IV). The isolation, analyses, and toxicity of these compounds toH. zea are presented.
113 citations
TL;DR: Volatiles from lesser grain borers, Hyzopertha dominica (F.) (Coleoptera: Bostrichidae), were collected on Porapak Q, and those from the male beetles were shown to contain two compounds, that were attractive individually and in combination to both sexes.
Abstract: Volatiles from lesser grain borers,Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae), were collected on Porapak Q, and those from the male beetles were shown to contain two compounds, that were attractive individually and in combination to both sexes. These compounds were identified as (S)-(+)-1-methylbutyl (E)-2-methyl-2-pentenoate and (S)-(+)-1-methylbutyl (E)-2,4-dimethyl-2-pentenoate by spectrometry and comparison with synthesized compounds. The two compounds have been assigned the trivial names dominicalure 1 and dominicalure 2, respectively. Synthesized samples of these compounds, individually and in combination, were effective in trapping both sexes in field studies.
103 citations
TL;DR: Human axillary odor was used in testing the ability of male and female subjects to distinguish between gender and individuals, and a cultural difference was found concerning partner's odor: though men classified it alike (predominantly pleasant), women differed.
Abstract: Human axillary odor was used in testing the ability of male and female subjects to distinguish between gender and individuals. The subjects also gave a qualitative evaluation of the odors. The tests were carried out in Japan, Italy, and Germany. Of all three cultures, 80% of the participants could significantly distinguish among the odor of individuals; 50% could identify the person correctly to whom the recognized odor belonged. Discrimination between male and female odor was significantly shown by 20% of Italian, 30% of German, and 60% of Japanese subjects. The qualitative evaluation of male and female odor was the same in the three cultures: male odor was classified more unpleasant and less pleasant than female odor. Men classified their own odor more unpleasant than women did with their own. A cultural difference was found concerning partner's odor: though men classified it alike (predominantly pleasant), women differed. Japanese and Italian women classified their partner's odor predominantly unpleasant, German women predominantly pleasant. In general the Japanese subjects classified the odors less often pleasant than the Italian and German subjects did.
101 citations
TL;DR: With the exception of the roots, significant changes in gross cardenolide content occurred for each sample type with time of collection during the growing season, whereas variation within this population was found to be small.
Abstract: Root, stem, leaf, and latex samples ofAsclepias eriocarpa collected from three plots in one population at 12 monthly intervals were assayed for total cardenolide content by spectroassay and for individual cardenolides by thin-layer chromatography From May to September mean milligram equivalents of digitoxin per gram of dried plant were: latices, 568 ≫ stems, 612 > leaves, 40 > roots, 25 With the exception of the roots, significant changes in gross cardenolide content occurred for each sample type with time of collection during the growing season, whereas variation within this population was found to be small Labriformin, a nitrogen-containing cardenolide of low polarity, predominated in the latices Leaf samples contained labriformin, labriformidin, desglucosyrioside, and other unidentified cardenolides In addition to most of the same cardenolides as the leaves, the stems also contained uzarigenin The roots contained desglucosyrioside and several polar cardenolides The results are compared with those for other cardenolide-containing plants, and discussed in relation to anti-herbivore defense based on plant cardenolide content Arguments are advanced for a central role of the latex in cardenolide storage and deployment which maximizes the defensive qualities of the cardenolides while preventing toxicity to the plant
98 citations
TL;DR: The volatile chemicals detectable by coupled capillary gas chromatography-mass spectrometry in the nest cell linings of four species in the bee generaColletes, Andrena, andLasioglossum are identical with the volatile components present in the Dufour's gland of females, suggesting this source for some of their cell-lining constituents.
Abstract: The volatile chemicals, detectable by coupled capillary gas chromatography-mass spectrometry, in the nest cell linings of four species in the bee generaColletes, Andrena, andLasioglossum are identical with, and limited to, the volatile components present in the Dufour's gland of females, suggesting this source for some of their cell-lining constituents. The extractable material that lines the cells ofTrachusa byssina, in contrast, is derived fromPinus resin, to which it can be chemically traced.
87 citations
TL;DR: Methylbutenol alone, the specific pheromone component of Ips typographus, elicited no response, but synergestic effects appeared when methyl butenol was combined withcis-verbenol and ipsdienol.
Abstract: Thanasimus formicarius (L.) responds to racemic ipsdienol and ipsenol and less to (S)-cis-verbenol. All three are pheromone components in several bark beetles of the genusIps. Synergistic effects appeared when the components were combined. Methylbutenol alone, the specific pheromone component ofIps typographus, elicited no response, but synergestic effects appeared when methylbutenol was combined withcis-verbenol and ipsdienol. The sympatric speciesThanasimus femoralis (Zett.) responds to (S)-cis-verbenol, while ipsdienol and ipsenol synergize the response.
87 citations
TL;DR: The solitary, endoparasitic ichneumonid,Hyposoter exiguae (Viereck) is a parasitoid of the tomato fruitworm,Heliothis zea (Boddie), and the toxicity of α-tomatine is attenuated in parasitoids reared from hosts fed on artificial diets that contain equimolar or supramolar amounts of 3β-OH-sterols admixed with α-Tomatine.
Abstract: The solitary, endoparasitic ichneumonid,Hyposoter exiguae (Viereck) is a parasitoid of the tomato fruitworm,Heliothis zea (Boddie). However, the parasitoid is deleteriously affected by the tomato glycoalkaloid, α-tomatine, ingested from hosts (H. zea) fed on artificial diets or semipurified extracts of tomato plants that contained α-tomatine. α-Tomatine causes prolonged larval development; disruption or prevention of pupal eclosion; deformation of antennal, abdominal, and genital structures; and reduction in adult weight and longevity of the parasitoid. These toxic effects are exacerbated when the dietary dose of α-tomatine is increased from 12 μmol to 20 μmol/g dry wt of diet. However, the toxicity of α-tomatine is attenuated in parasitoids reared from hosts fed on artificial diets that contain equimolar or supramolar amounts of 3β-OH-sterols admixed with α-tomatine. Further, the toxicity of extracts from the foliage of different cultivars of tomatoes toH. exiguae is contingent upon the composite levels of α-tomatine and total phytosterol (free and esterified). Cultivars with a low total sterol-tomatine ratio are more toxic toH. exiguae. The possible mode of action of α-tomatine toxicity toH. exiguae by disruption of sterol metabolism is discussed.
TL;DR: Although the whole blend was found to be an effective male attractant, the deletion of alcohols from the blend increased trap captures considerably, and although the binary mixture of (Z)-9-hexadecenal and (Z-11- hexadeCenal caught some maleH.
Abstract: Eight compounds were isolated from the sex pheromone gland ofHeliothis subflexa (Gn.) and identified as hexadecanal, (Z)-9-hexadecenal, (Z)-11-hexadecenal, (Z)-7-hexadecen-1-ol acetate, (Z)-9-hexadecen-1-ol acetate, (Z)-11-hexadecen-1-ol acetate, (Z)-9-hexadecen-1-ol, and (Z)-11-hexadecen-1-ol. Although the whole blend was found to be an effective male attractant, the deletion of alcohols from the blend increased trap captures considerably. Further, although the binary mixture of (Z)-9-hexadecenal and (Z)-11-hexadecenal caught some maleH. subflexa, significant increases in captures were noted when the three acetate components were included in the blend.
TL;DR: The lack of response to frass from larvae reared on corn was shown to be a result of a lack of some appropriate chemical(s) in the corn.
Abstract: In laboratory experiments conducted to compare the kairomonal activity forMicroplitis croceipes (Cresson) of frass fromHeliothis zea (Boddie) larvae fed on different host plants,M croceipes females responded to extracts of frass from larvae reared on cotton or soybeans but not on corn The lack of response to frass from larvae reared on corn was shown to be a result of a lack of some appropriate chemical(s) in the corn
TL;DR: It is found that the searching behavior of two acarine predators for prey, Amblyseius fallacis and Phytoseiulus macropilis, is affected by the following stimuli: prey silk and associated feces, whose combined physical and chemical properties elicit reduction in the rate of predator movements and longer halts.
Abstract: We found that the searching behavior of two acarine predators,Amblyseius fallacis andPhytoseiulus macropilis, for prey,Tetranychus urticae, is affected by the following stimuli: (1) prey silk and associated feces, whose combined physical and chemical properties elicit reduction in the rate of predator movements and longer halts; (2) kairomone extracted from prey silk and associated feces, which, upon contact, elicits frequent predator return to prey-inhabited locales; and (3) predator-emitted marking pheromone, which elicits shorter duration of search in presearched prey locales. We also found that treatment of filter paper with prey kairomone or silk enhanced predator location of prey eggs, leading us to speculate that application of synthetic prey kairomone could be useful in pest management programs.
TL;DR: Improvements in a synthetic diet for use in a bioassay to screen for feeding deterrents against Schizaphis graminum, greenbug, are reported.
Abstract: Improvements in a synthetic diet for use in a bioassay to screen for feeding deterrents againstSchizaphis graminum, greenbug, are reported. Feeding on the synthetic diet was highly pH dependent with maximum feeding occurring at about pH 8.0. The bioassay was used as a guide in the isolation of feeding deterrent substances from aphid-resistant lines of sorghum (Sorghum bicolor). The major greenbug feeding deterrents isolated from sorghum leaves wereP-hydroxybenzaldehyde (ED50 0.13%), dhurrin (ED50 0.16%), and procyanidin (ED50 0.08%).
TL;DR: Levels of phenolic acids in healthy plants of sorghum bicolor differ considerably with cultivar and always decrease as the plant matures, and laboratory- and field-grown plants show significant differences in phenolics.
Abstract: Levels of phenolic acids in healthy plants ofSorghum bicolor differ considerably with cultivar and always decrease as the plant matures. Laboratory- and field-grown plants show significant differences in phenolics. Environmental factors, particularly light intensity, influence the concentration of phenolics in sorghum. Attack by insects and pathogenic fungi also increase the phenolic content of the plants to varying degrees dependent on the cultivar and the stage of growth of the plant.
TL;DR: Dendroctonus brevicomis was attracted to a mixture of theIps paraconfusus pheromones, ipsenol,cis-verbenol, and ipsdienol at 10−9 g each/μl but was not attracted to these phersomones at higher and lower release rates.
Abstract: Dendroctonus brevicomis was attracted to a mixture of theIps paraconfusus pheromones, ipsenol,cis-verbenol, and ipsdienol at 10−9 g each/μl but was not attracted to these pheromones at higher and lower release rates.I. paraconfusus was not attracted to theD. brevicomis pheromonesexo-brevicomin, frontalin, and myrcene at any release rate tested. Increased release rates of a mixture of the three pheromones ofI. paraconfusus inhibited the attraction ofD. brevicomis to its synthetic pheromones. A mixture of ipsenol + ipsdienol orcis-verbenol alone failed to cause inhibition indicating that at least two of theI. paraconfusus pheromones are required to inhibit the response ofD. brevicomis. The pheromones ofD. brevicomis did not inhibit the attraction ofI. paraconfusus to its pheromones; however, verbenone was a potent inhibitor.
TL;DR: Four species of Acridoidea were fed on wheat leaves with and without the condensed tannin, quebracho, and consumption, digestibility, and utilization of food were unaffected at up to 10% dry weight, however, at higher concentrations the consumption and the efficiency of conversion of digestion were reduced, although digestibility was little affected.
Abstract: Four species of Acridoidea were fed on wheat leaves with and without the condensed tannin, quebracho. In no case was it deleterious to survival and growth at levels below about 10% dry weight on the food. Similarly, consumption, digestibility, and utilization of food were unaffected at up to 10% dry weight. At higher concentrations, however, the consumption and the efficiency of conversion of digestion were reduced, although digestibility was little affected. The possible mechanisms for such tolerance are discussed, and contrast made with insects which are very sensitive to ingested condensed tannin.
TL;DR: 2-Tridecanone, a toxin important in the insect resistance of PI 134417, was significantly more abundant in the foliage of plants grown under the long-than the short-day regimes and the density of glandular trichomes, which secrete 2-tridecan one, was influenced by an interaction between day length and light intensity.
Abstract: First instarManduca sexta (L.) larvae confined on foliage fromLycopersicon hirsutum f.glabratum (accession PI 134417) plants grown under a long-day regime exhibited greater mortality than larvae on foliage from plants grown under a short-day regime. 2-Tridecanone, a toxin important in the insect resistance of PI 134417, was significantly more abundant in the foliage of plants grown under the long-than the short-day regimes. Light intensity influenced neither 2-tridecanone levels nor the expression of resistance. The density of glandular trichomes, which secrete 2-tridecanone, was influenced by an interaction between day length and light intensity.
TL;DR: The behavioral response of Trichogramma pretiosum Riley females to the kairomone found in Heliothis zea (Boddie) moth scales is examined.
Abstract: The behavioral response ofTrichogramma pretiosum Riley females to the kairomone found inHeliothis zea (Boddie) moth scales is examined.
TL;DR: The half-life of alcohol sex pheromones, 1-alkanols, acetate, and an epoxide (disparlure) were determined on natural rubber septa as discussed by the authors.
Abstract: The half-lives (t1/2) of alcohol sex pheromones, 1-alkanols, acetate sex pheromones, and an epoxide (disparlure) were determined on natural rubber septa. Thet1/2 values for the homologous alcohols from decanol to heptadecanol increased regularly from 2.2 to 1117 days, but thet1/2 of octadecanol was 609 days. Thet1/2 values of (Z)7-, (E)7-, and (Z)9-tetradecen-1-ol acetates were 154, 168, and 199 days, respectively, whereas those of five other tested 14-carbon acetates ranged from 310 to 350 days. The dependence oft1/2 values on chain length and double-bond position is consistent with the hypothesis that molecular size is an important variable affectingt1/2 values. Also, in accordance with the hypothesis, when aZ-alkenyl compound has a much shortert1/2 than the corresponding saturated compound, thet1/2 values of theZ compound and itsE isomer may be quite different. Thus, (E)-9-tetradecen-l-ol acetate had at1/2 of 331 days. Thet1/2 of disparlure was 180 days. The effect of thecis-7,8 epoxide group is apparently similar to that of the olefin group in lowering thet1/2 below the value that would be expected solely on the basis of chain length.
TL;DR: A high-efficiency collection device for sex pheromones volatized from forcibly extruded female glands is described and small quantities of distilled carbon disulfide are used to rinse the glass wool.
Abstract: A high-efficiency collection device for sex pheromones volatized from forcibly extruded female glands is described. Filtered nitrogen gas is the carrier and glass wool the adsorbent. Small quantities of distilled carbon disulfide are used to rinse the glass wool. Recovery efficiency of synthetic compounds was usually 90–100%, and a mean of 2.4 ± 0.65 SD ng/min of (Z)-7-dodecenyl acetate was recovered in emissions from individualTrichoplusia ni (Hubner) glands.
TL;DR: Three compounds have been identified as components of the sex pheromone emitted by females of the saltmarsh caterpillar moth, Estigmene acrea, and there is evidence that the antennal acceptor site for III is chiral.
Abstract: Three compounds have been identified as components of the sex pheromone emitted by females of the saltmarsh caterpillar moth,Estigmene acrea (Drury). These are (Z,Z)-9,12-octadecadienal (I), (Z,Z,Z)-9,12,15-octadecatrienal (II), and (Z,Z)-3,6-cis-9,10-epoxyheneicosadiene (III). In female tip extract they were found in a ratio of 1∶6∶25, respectively, and in trapped female effluvia the ratio was 1∶6∶27, respectively. Combinations of III with either I or II elicited sustained upwind flight in a wind tunnel, but none of these compounds by themselves did so. There is evidence that the antennal acceptor site for III is chiral.
TL;DR: Evidence for the existence of a male-produced aggregation pheromone secreted from the prothoracic femoral setiferous sex patch of Tribolium castaneum is reported.
Abstract: Evidence for the existence of a male-produced aggregation pheromone secreted from the prothoracic femoral setiferous sex patch ofTribolium castaneum is reported. Both sexes were attracted toca. 60 ng of crude secretion. Males and females perceive the pheromone on the day of emergence while perception differs between the sexes: male response reaches a maximum on day 1 posteclosion, when tested at <1, 1, and 30 days; females show a maximum response at 30 days posteclosion. Behavioral responses to pheromone odors and a complex Chromatographic profile are reported.
TL;DR: The phytotoxicity produced during decomposition of rice straw in soil was evaluated under both constant and changing temperature conditions and the quantity of toxins released reached highest levels six weeks after incubation and gradually disappeared after twelve weeks.
Abstract: The phytotoxicity produced during decomposition of rice straw in soil was evaluated under both constant and changing temperature conditions. Bioassay tests showed that the aqueous extract from a soilstraw mixture after incubation at constant temperature was more than twice as phytotoxic as the extract from soil incubated alone. The phytotoxicity was highest at 20–25 ° C. Temperatures above 25 ° C enhanced rice straw decomposition and also degraded the phytotoxic substances more rapidly. After incubation of soil mixtures under changing temperature regimes in a phytotron, the phytotoxicy of the soil aqueous extracts increased in the following order: soil alone < soil + fertilizer < soil + straw < soil + straw + fertilizer. Growth inhibition of lettuce or rice seedlings was also at the highest at the temperature range of 25–30 ° C irrespective of the direction of temperature changes from either low to high or vice versa. Five phytotoxic phenolics,p-hydroxybenzoic, vanillic,p-coumaric, syringic, and ferulic acids, were obtained from both the aqueous extract and residue of the incubated soil samples and were quantitatively estimated by chromatography. The amount of phytotoxins found in various soil mixtures followed the same increasing order as that found by the seed bioassay test. Although no definite distribution pattern of the phenolics in the incubated soil samples can be attributed to temperature variations, the amount of the phenolics was likely higher in the samples incubated at 25 ° C than at either 15 ° C or 35 ° C. The quantity of toxins released during decomposition of rice straw in soil reached highest levels six weeks after incubation and gradually disappeared after twelve weeks.
TL;DR: A volatile component of this species' mandibular gland secretion, linalool, increases flight activity and directs local search behavior in aerially patrolling males.
Abstract: Males of the vernal ground nesting bee,Colletes cunicularius, actively search their nesting aggregations for emerging virgin females. Males often detect and unearth preemergent virgin males and females which have not yet dug up to the soil surface. Field experiments indicate that the odors from one unmated individual are sufficient to both excite males and direct their excavation of the virgin bee. A volatile component of this species' mandibular gland secretion, linalool, increases flight activity and directs local search behavior in aerially patrolling males. Linalool is detectable by coupled gas chromatography-mass spectrometry in association with the digging activities of either sex.
TL;DR: The volatile components of the Dufour's gland secretion of female halictid bees have been examined in 18 Nearctic species and a series of eight esters containing branched C5-alkenols and fatty acids has been identified in several species.
Abstract: The volatile components of the Dufour's gland secretion of female halictid bees have been examined in 18 Nearctic species belonging toAgapostemon, Augochlora, Augochlorella, Augochloropsis, Dialictus, Evylaeus, Halictus, andLasioglossum. Nine saturated and unsaturated macrocyclic lactones ranging from C18 to C26 have been identified. Four of these compounds, the saturated C26 and the unsaturated C20, C22, and C24 lactones, are new natural products reported for halictine bees. A series of eight esters containing branched C5-alkenols and fatty acids has been identified in several species. The cell linings and pollen ball inAugochlora pura pura contain the same major lactones as the Dufour's gland. A discussion of the significance of the Dufour's gland secretion for apoid systematics and its function in the Halictidae is presented.
TL;DR: The sex attractant pheromone produced by female Dacus oleae Gmelin is a mixture of four compounds, two of which are found in the rectal gland and the other two elsewhere in the insect body.
Abstract: The sex attractant pheromone produced by femaleDacus oleae Gmelin is a mixture of four compounds, two of which are found in the rectal gland and the other two elsewhere in the insect body. The ratio of these compounds in the pheromone blend was measured. Biological activity of all four compounds and their combinations was studied in lab and field cage tests. The most abundant compound in the mixture (55.7%) shows the highest biological activity. Recombination of all compounds significantly increases activity of the main compound.
TL;DR: Mating success of G. molesta pairs confined in small cages apparently was not affected by the presence of relatively high concentrations of the binary acetate and the acetate-alcohol blends, suggesting that habituation and/or adaptation of male response, at least for comparatively “close-range” behaviors, did not occur.
Abstract: The relative efficacy of disruptant blends comprised of different combinations of the Oriental fruit moth's pheromone components was determined in field tests. Disruption was evaluated by comparing male moth catch at synthetic and female-baited traps in disruptant and non-treatment areas. Three atmospheric dosages of a 8-dodecenyl acetate (93.5%Z∶6.5%E) blend, representing two successive 10-fold decreases in concentration (2.5 × 10−2 g/hectare/day to 2.5 × 10−4 g/hectare/day) were tested alone and in combination with an additional percentage of (Z)-8-dodecen-1-ol. Male moth orientation to traps was eliminated in plots exposed to the two highest binary acetate dosages. However, significantly more males were captured in synthetic-baited traps in the lowest acetate-alone treatment, indicating a diminution of disruption efficiency. In contrast, inclusion of (Z)-8-dodecen-1-ol in the disruptant blend effected essentially complete disruption of orientation at all concentrations tested. Mating success ofG. molesta pairs confined in small cages apparently was not affected by the presence of relatively high concentrations of the binary acetate and the acetate-alcohol blends. This suggests that habituation and/or adaptation of male response, at least for comparatively “close-range” behaviors, did not occur.
TL;DR: Lobsters can detect odors from two natural prey species, the horse musselModiolus modiolus and the blue musselMytilusedulis, and when lobsters fed exclusively on one of these two prey species for one month, their behavioral response threshold for the prey odor from this species was lowered relative to the threshold from the nonexperienced prey.
Abstract: Lobsters can detect odors from two natural prey species, the horse musselModiolus modiolus and the blue musselMytilusedulis. When lobsters fed exclusively on one of these two prey species for one month, their behavioral response threshold for the prey odor from this species was lowered relative to the threshold for odor from the nonexperienced prey.