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  • Lepidoptera  (65)
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  • 1
    ISSN: 1572-8889
    Keywords: mate-locating behavior ; butterfly ; Euphydryas chalcedona ; Lepidoptera ; pupation sites ; sexual discrimination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Males of the checkerspot butterfly (Euphydryas chalcedona)patrol and perch near but not on the larval foodplant in search of females. Experiments with tethered butterflies show that searching males chase virgin females for longer times than they do mated females or males. The larvae leave the larval food-plant to pupate. The correspondence between the distance from the larval foodplant to pupation sites and where males search for females suggests that male mate-locating behavior has evolved to maximize the rate of encounters with newly emerged, virgin females. These conclusions are compared to a recent analysis of butterfly mating systems by Odendaal et al. (Am. Nat. 125: 673–678, 1985).
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  • 2
    ISSN: 1572-8889
    Keywords: Grapholita molesta ; Lepidoptera ; optomotor anemotaxis ; pheromone ; counterturn ; zigzag ; flight ; orientation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract As the ratio of (E)-8-dodecenyl acetate (E8–12∶Ac) to (Z)-8-dodecenyl acetate (Z8–12∶Ac) increased past optimal low levels in the pheromone blend, fewer males were able to fly 2.5 m upwind to the source. The tracks of males that flew in plumes of such high-(E)off-blends were slower and narrower than those of males flying to lower-(E)blends. The tracks were narrower, first of all, because as the proportion of E8–12∶Ac increased, the males steered more into the wind. More of their thrust was directed upwind and therefore their groundspeed to either side of the windline was reduced. In addition, males also reduced their airspeeds to high-(E)blends, which contributed to the decreased groundspeeds and narrower tracks. No significant changes in the frequency of counterturning were found in response to increasing proportions of E8–12∶Ac. The inability to continue upwind flight in a plume of an off ratio was indicated by in-flight arrestment in the plume. Arrestment resulted from changes in the course angles steered by the males and the airspeeds flown.
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  • 3
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    Entomologia experimentalis et applicata 48 (1988), S. 213-223 
    ISSN: 1570-7458
    Keywords: Lepidoptera ; Yponomeutidae ; interspecific crosses ; hybrids ; sex-pheromone communication ; host-plant preference
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé 1. Des individus d'espèces très proches à l'intérieur du complexe Yponomeuta padellus ont été croisés; les hybrides ont été croisés entre eux et leurs fécondité et viabilité examinées. 2. Le taux d'accouplements a été généralement plus faible que celui des témoins. Les croisements Y. malinellus x Y. rorellus, Y. padellus x Y. rorellus, et Y. rorellus x Y. malinellus n'ont donné aucune descendance, tandis que les chenilles de Y. malinellus x Y. cagnagellus, Y. padellus x Y. cagnagellus et Y. padellus x Y. malinellus sont mortes avant le stade imaginal. Bien que des descendants féconds des deux sexes pouvaient être obtenus à partir de la plupart des croisements, leurs effectifs étaient faibles. Seuls les croisements où intervenaient des femelles de Y. cagnagellus, ont fourni assez de filles pour permettre des expériences avec des phéromones. 3. La viabilité, le rythme circadian de l'activité sexuelle, les réponses aux phéromones et le choix de la plante pour la ponte ont été examinés chez les hybrides des 3 croisements réussis avec Y. cagnagellus comme mère. 4. Le poids des chrysalides et la durée du développement de cette progéniture a montré une dominance de Y. cagnagellus, tandis que les caractères morphologiques étaient intermédiaires. Des indices d'un développement difficile ont été une modification du rythme d'éclosions et un biais dans la fréquence des sexes. On a aussi, observé une certaine stérilité, c'està-dire que 10% environ des F1 cagnagellus x malinellus étaient intersexués, et que la plupart des femelles F1 cagnagellus x rorellus n'ont pas présenté de comportement d'appel. Les femelles ont manifesté une légère préférence pour appeler à partir de la plante hôte maternelle. L'âge du premier appel a révélé une dominance partielle de Y. malinellus et de Y. padellus. 5. Les mâles hybrides ont répondu fortement aux phéromones des femelles hybrides correspondantes. Les réponses des hybrides mâles F1 et F2 aux phéromones parentales ont montré que la réponse était orientée spécifiquement par la dominance de Y. cagnagellus sur Y. malinellus et une codominance de Y. cagnagellus et Y. padellus. 6. Ces résultats ont indiqué les possibilités d'échanges géniques en l'absence de barrière avant la copulation. Ainsi, l'isolement reproductif des 4 espèces est maintenu par la spécificité des phéromones sexuelles femelles et renforcé par les signaux du comportement de pariade.
    Notes: Abstract Interspecific crosses were made among four closely related members of the Yponomeuta padellus-complex. The results show the potential for gene exchange in the absence of pre-mating barriers. However, mating success was generally lower in the interspecific crosses than in the control crosses. No progeny were obtained from crosses between Y. malinellus Zeller x Y. rorellus (Hübner), Y. padellus (L.) x Y. rorellus and Y. rorellus x Y. malinellus, whereas larvae from Y. malinellus x Y. cagnagellus (Hübner), Y. padellus x Y. cagnagellus and Y. padellus x Y. malinellus did not reach the adult stage. Hybrids of three successful crosses with Y. cagnagellus as maternal species were examined for viability, circadian rhythm of sexual activity, sex-pheromone responses and female host-plant preferences. Developmental problems were found for the crosses cagnagellus x malinellus and cagnagellus x rorellus. Pupal weights and developmental time indicated dominance of Y. cagnagellus, while morphological characters were intermediate to the parents. The age of first calling indicates incomplete dominance of Y. malinellus and Y. padellus, while female moths showed a slight preference for the maternal host plant for calling activities. Hybrid males showed high responsiveness to the corresponding hybrid females. Responses to the parental species indicate that the inheritance of the pheromone-response specificity is governed by a dominance of Y. cagnagellus over Y. malinellus and co-dominance between Y. cagnagellus and Y. padellus.
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  • 4
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    Cellular and molecular life sciences 44 (1988), S. 788-789 
    ISSN: 1420-9071
    Keywords: Yponomeuta vigintipunctatus ; Lepidoptera ; Yponomeutidae ; diapause ; photoperiodic induction curves ; low temperature influence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The long-day insectYponomeuta vigintipunctatus was subjected to various combinations of temperature and photoperiod. The photoperiodic induction curve at 10°C resembled the one at 20°C, but with a shift of the critical photoperiod towards the shorter day-length. Such unusual averting of diapause at lower temperatures in combination with intermediate long-day photoperiods has still been described in only few insect species of the temperate zone.
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  • 5
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    Entomologia experimentalis et applicata 46 (1988), S. 29-38 
    ISSN: 1570-7458
    Keywords: Lepidoptera ; Yponomeuta cagnagellus ; Yponomeuta irrorellus ; Yponomeuta plumbellus ; Yponomeuta padellus ; sex pheromone ; reproductive isolation ; gas chromatography ; tetradecyl acetate ; (E)-11-tetradecenyl acetate ; (Z)-11-tetradecenyl acetate ; hexadecyl acetate ; tetradecanol ; (E)-11-tetradecanol ; (Z)-11-tetradecenol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé L'analyse a porté sur les phéromones sexuelles de 3 Yponomeutidae, trouvés en sympatrie sur le fusain. Des expériences sur le comportement de Y. cagnagellus ont montré que la fraction acétate de tétradécyl de la phéromone synergise les fractions connues antérieurement: (E)-11- et (Z)-11-acétates de tétradécényl, lorsque les proportions sont 37/2/100. L'analyse en chromatographie gazeuse d'extraits de glandes à phéromone de Y. irrorellus a mis en évidence, dans les proportions approximatives suivantes 68/56/100/9/6/8/7, de l'acétate de tétradécyl, des (E)-11 et (Z)-11 acétates de tétradécényl, du tétradécanol, des (E)-11 et (Z)-11-tétradécénols, et de l'acétate d'hexadécyl. Un mélange de ces composés a provoqué un vol intégral contre le vent des mâles dans un tunnel à vent et a attiré les mâles dans la nature. L'analyse des extrait de glandes à phéromone de Y. plumbellus a donné de l'acétate de tétradécyl, du (E)-11-acétate de tétradécényl et du (Z)-11-acétate de tétradécényl, dans les proportions: 50/150/100. Une étude par élimination dans la nature a montré que les acétates non saturés étaient les composés fondamentaux de la phéromone. La teneur en (Z)-11-acétate de tétradécényl de la glande à phéromone de Y. plumbellus était d'environ 0.5 ng par femelle, soit approximativement le dixième de celle observée chez les deux autres espèces. Une très faible attraction croisée a été trouvée avec des phéromones totalement synthétisées. Lorsque l'acétate de (E)-11-tétradécényl a été enlevé des phéromones de Y. irrorellus et Y. plumbellus, le reliquat a attiré des nombres significatifs de Y. cagnagellus. Nous en concluons que des mélanges de trois composés ou plus, avec des proportions spécifiques des isomères (E) et (Z), sont indispensables pour une activité complète et pour maintenir un isolement reproductif précopulatoire entre les espèces.
    Notes: Abstract The sex pheromones produced by virgin females of three species of small ermine moths occurring sympatrically on the European spindle tree were analysed by gas chromatography and the synthetic compounds tested against male moths in the laboratory and field. Pheromone gland extracts of Yponomeuta cagnagellus were shown to contain tetradecyl acetate, (E)-11- and (Z)-11-tetradecenyl acetate, tetradecanol, (E)-11- and (Z-11-tetradecenol and hexadecyl acetate in 30/3/100/6/0/7/42) ratio. Wind tunnel bioassays and field tests showed that (E)-11-tetradecenyl acetate primary pheromone components, and that tetradecyl acetate synergised their attractiveness. The alcohols were unimportant in these tests. Analysis of the pheromone gland extracts from Y. irrorellus showed the above components in 68/56/100/9/6/8/17 ratio, and a mixture of these attracted male moths in laboratory and field. Omission of either unsaturated acetate gave unattractive mixtures, and the alcohols were also found to be important for attraction. Pheromone gland extracts from Y. plumbellus were shown to contain the seven components in 46/148/100/20/20/13/25 ratio. Field tests showed that the two monounsaturated acetates are primary pheromone components, and removal of the alcohols had no significant effect. The titre of (Z)-11-tetradecenyl acetate in Y. plumbellus pheromone gland extracts was approximately 0.5 ng per female, one tenth the titre in the other two species. It is concluded that mixtures of three or more pheromone components with specific E/Z ratio are essential for full attraction and contribute towards premating reproductive isolation of the three species. Other factors such as rate of pheromone emission, time of flight and height of flight may also contribute to reproductive isolation.
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  • 6
    ISSN: 1570-7458
    Keywords: Ostrinia nubilalis ; Pyralidae ; Lepidoptera ; Pseudoperichaeta nigrolineata ; Tachinidae ; Diptera ; larval development ; host-parasitoid relationship ; diapause ; development synchronization ; ecdysteroids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé Les interrelations entre O. nubilalis et le tachinidae P. nigrolineata ont été étudiées dans des conditions abiotiques telles que l'hôte présente un développement avec diapause. La rupture de la diapause a été obtenue par modifications des conditions abiotiques et/ou injection d'ecdystérone. Si le passage au froid a lieu 25 jours après la mue 4/5 et s'il dure 10 semaines, plus de 90% des larves non parasitées lèvent leur diapause. Le temps nécessaire pour obtenir la chrysalidation est corrélé avec l'âge à la mise au froid et surtout avec la durée du froid. Les injections d'ecdystérone, 25 jours après la mue 4/5, chez les larves non parasitées et n'ayant pas séjourné au froid, provoquent la levée de diapause dans un fort pourcentage de cas, mais seulement si les larves ont été transférées en photopériode longue; le temps de chrysalidation est fortement réduit chez les larves injectées par rapport aux témoins placés sous la même photopériode. Chez les larves d'O. nubilalis parasitées au début du 5ème stade larvaire, les larves de P. nigrolineata se développent de la même façon que chez les non diapausantes jusqu'au début du 2ème stade, puis la croissance s'arrête aux environs de 1 mg. Par modification des conditions abiotiques, la larve du parasitoïde ne reprend sa croissance qu'à la levée de diapause de l'hôte et continue ensuite son développement jusqu'à la pupaison qui intervient 25–30 jours après les modifications. Cette synchronisation étroite des développements du parasitoïde et de l'hôte peut être rompue par l'injection d'ecdystérone dans l'hôte; en effet, une faible dose induit la reprise de la croissance du parasitoïde, sans provoquer l'apolyse de l'hôte. Des doses plus élevées provoquent à la fois la reprise immédiate du développement de P. nigrolineata (la formation des pupes intervient alors 6–10 jours après) et l'apolyse de l'hôte. Le parasitoïde augmente la sensibilité de l'hôte: avec la même dose, le pourcentage d'apolyse est plus élevé chez les hôtes parasités que chez les non parasités.
    Notes: Abstract The developmental relationships between Ostrinia nubilalis Hübner (Lepidoptera, Pyralidae) and the tachinid parasitoid Pseudoperichaeta nigrolineata Walker (Diptera, Tachinidae) are described under abiotic conditions which induce development of the host with diapause. Diapause termination was accomplished by modifications of abiotic conditions and/or by ecdysterone injection. Pupation time was correlated with the age at chilling and with the chilling period. Ecdysterone injection in non-parasitized larvae, 25 days after the 4/5 moult, gave a high percentage of diapause termination only under a long day photoperiod and strongly reduced the pupation time. In diapausing larvae parasitized at the beginning of the fifth instar, P. nigrolineata larva develops in the same way as in non-diapausing ones during the first instar, but stops growth in the second, near a weight of 1 mg. When diapause was broken by modifications of obiotic conditions, the parasitoid larva resumes its growth only at host diapause termination (pupariae are obtained 25–30 days after the modifications). The close synchronization between parasitoid and host development is broken by injection of low dose of ecdysterone. Higher doses induce at once parasitoid growth (pupariae are obtained 6–10 days thereafter) and also host apolysis. The parasitoid larvae increase the host sensitivity to exogenous ecdysteroids.
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  • 7
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    Entomologia experimentalis et applicata 46 (1988), S. 93-100 
    ISSN: 1570-7458
    Keywords: antifeedants ; aristolochic acid ; armyworm ; feeding ; desensitization ; Lepidoptera ; Noctuidae ; Spodoptera frugiperda
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé L'avenir des phagodissuadants en protection des cultures dépend, en particulier, de l'aptitude des insectes à devenir insensibles à ces substances. Les phagodissuadants sont classés en relatifs ou absolus, suivant que les insectes consomment les tissus traités ou se laissent mourir de faim. Cette propriété dépend beaucoup de la structure chimique, mais les paramètres biologiques n'ont pas été étudiés à fond. Des expériences ont donc été entreprises pour apprécier les effets combinés de jeûne et d'autres facteurs physiologiques dans l'apparition et l'évolution de la désensibilisation chez une espèce polyphage: Spodoptera frugiperda (Lep. Noctuidae). Des expériences préliminaires ont montré qu'un alcaloïde, l'acide aristolochique, est un puissant phagodissuadant pour S. frugiperda. Les chenilles, réparties en deux groupes expérimentaux, ont toutes été isolées et ont reçu chacune deux feuilles de Phaseolus lunatus: une témoin et une traitée avec 1000 ppm. Dans le groupe 1), les feuilles étaient remplacées dès consommation; dans le groupe 2), elles ne l'étaient pas. Un puissant effet dissuadant a été observé tout au long de l'expérience pour le groupe 1); dans le groupe 2), les chenilles ont finalement consommé les feuilles traitées. L'apparition de la désensibilisation était liée au jeûne. Quelques individus ont commencé à s'alimenter sur la rondelle traitée 3,5 heures aprés avoir totalement consommé la rondelle témoin; le temps médian du début de cette consommation a été de 5,7 h. Une fois la répulsion surmontée, les chenilles ont consommé le feuillage traité de la même façon que le feuillage témoin. Les expériences ont été recommencées avec les mêmes insectes, mais sans que les feuilles témoins aient alors été remplacées dans aucun des 2 groupes. Dans cette seconde expérience, les chenilles, qui avaient précédemment consommé des feuilles traitées, sont à nouveau dissuadées lors de choix binaires; cependant elles ont mangé plus rapidement les feuilles traitées, que ne l'ont fait les chenilles qui avaient disposé d'une source inépuisable de feuilles témoins. Elles se sont alimentées aussi plus facilement et plus généralement au cours de cette seconde expérience qu'au cours de la première. Quoi qu'il en soit, les deux groupes ont présenté finalement une désensibilisation. Un modèle mathématique général est proposé pour évaluer l'apparition et l'évolution de la désensibilisation. Les possibilités d'utilisation des phagodissuadants dans la protection des cultures sont discutées à la lumière de ces résultats.
    Notes: Abstract Fall armyworm larvae, Spodoptera frugiperda (J. G. Smith), were exposed to leaf disks treated with the feeding deterrent aristolochic acid under two types of regimes: In group 1, untreated leaf tissue was replenished as soon as it was consumed; in group 2, the control tissue was not replenished. A strong feeding deterrence was evident during the early stages of the assay in both groups, but eventually declined in group 2. When the experiment was continued through a second 24 h period, the control tissue was not replenished for either group. During this second trial, group 2 larvae, which had previously fed on treated tissue, fed more rapidly on treated tissue than did group 1 larvae. Moreover, group 2 larvae fed more readily and extensively on treated tissue than they had in the first trial. The time for the onset of behavioral desensitization was determined by subtracting the median onset of feeding on untreated tissue from the median interval between when a larva finished all of the control tissue and when it started feeding on treated tissue under no-choice conditions. Once larvae began to feed on treated tissue, their rate of consumption was equal to that of larvae feeding on control tissue. A general model for determining the onset and degree of desensitization was developed. The implications of these results for future experiments aimed at determining the underlying physiological mechanisms and the use of antifeedants in plant protection are discussed.
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  • 8
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    Entomologia experimentalis et applicata 46 (1988), S. 133-140 
    ISSN: 1570-7458
    Keywords: Lepidoptera ; larvae ; geotaxis ; orientation ; Geometridae ; Ectropis excursaria ; gravity ; wandering stage
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé Un comportement d'escalade du premier stade d'E. excursaria correspondant à l'addition des réponses à la gravité et à la lumière, est suggéré par la courbe d'intensité de la réponse à la lumière, dans un plan vertical (où la gravité constitue un stimulus en opposition avec la lumière) et un plan horizontal (où la gravité n'est pas en opposition). La réponse à la gravité a été modifiée par la courbure de la surface à escalader et du degré de privation d'aliment des chenilles. Sur une surface d'escalade de 2 cm de diamètre, l'orientation par rapport à la gravité se produit entre 20 et 30° par rapport à l'horizontale. Das run champ de centrifugation, un comportement analogue à une géotaxis négative se produit pour une accélération de 3,5 m s−2. L'analyse des tendances géotactiques des chenilles à tourner sur des plans inclinés suggère qu'elles présentent un comportement métagéotactique pour les inclinaisons de 40 à 90°. Des expériences d'immobilisation laissent penser que les antennes jouent un rôle dans la perception de la gravité. Les chenilles de stades ultérieurs ont présenté une géotaxie négative bien que la réponse à la gravité disparaisse chez les chenilles vagabondes en prénymphe. La prénymphose est aussi caractérisée par une inversion des réponses à la lumière.
    Notes: Abstract The intensity-response curve to light in a vertical plane (where gravity was a conflicting stimulus to light) and a horizontal plane (where gravity was not a conflicting stimulus) suggests that the climbing behaviour of the first instar Ectropis excursaria (Guénée) is consistent with a summation of response to gravity and a response to light. Response to gravity was affected by the curvature of the crawling surface and the level of food deprivation of the caterpillars. On a 2 cm diameter crawling surface orientation to gravity occurred at an inclination between 20° and 30° from the horizontal. In a centrifugal field, a behaviour analogous to negative geotaxis occurred at accelerations of 3.5 ms−2. Analysis of the geotactic turning tendencies of the caterpillar on flat inclined planes suggests that they exhibit meta-geotactic behaviour from inclinations of 40 to 90°. Negative geotaxis was exhibited by the caterpillars of later stadia although a response to gravity was lacking in the prepupal wandering caterpillars. The pre-pupal stage was also characterized by a reversal of the response to light.
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  • 9
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    Entomologia experimentalis et applicata 46 (1988), S. 149-153 
    ISSN: 1570-7458
    Keywords: Lepidoptera ; Pyralidae ; Chilo partellus maize ; resistance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé L'étude a porté sur la croissance et la production avec différents niveaux de minage des tiges de 4 cultivars de maïs, lors de divers degrés de contamination artificielle par des chenilles de C. partellus. Le cultivar sensible ‘Inbred A’ souffre plus des mines de C. partellus que ICZ1-CM, ICZ2-CM et Katumani composite B. Les mines influent significativement sur la croissance des 4 cultivars. Il y a une corrélation négative significative entre le minage des tiges et la production pour les cultivars ‘Inbred A’ et Katumani composite B, mais la relation n'est pas significative pour ICZ1-CM et ICZ2-CM. Les différences entre le minage des tiges et la récolte des 4 cultivars sont dues aux différents degrés de minage des tiges de ces cultivars par C. partellus.
    Notes: Abstract The effects of different degrees of stem tunneling caused by different levels of artificial infestation by the larvae of Chilo partellus (Swinhoe) on growth and yield of 4 maize cultivars were studied. The susceptible ‘Inbred A’ suffered much more tunneling than ICZ1-CM, ICZ2-CM and Katumani Composite B. This tunneling influenced significantly the plant growth of all the four cultivars. There was a significant negative correlation between tunneling and yield for the cultivars ‘Inbred A’ and Katumani Composite B, but such a relationship was not significant for ICZ1-CM and ICZ2-CM. Such differences in the relationships between tunneling and yield among the 4 cultivars are due to different degrees of tunneling caused by C. partellus larvae to the plants of these cultivars.
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  • 10
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    Entomologia experimentalis et applicata 48 (1988), S. 293-300 
    ISSN: 1570-7458
    Keywords: Lepidoptera ; Noctuidae ; Heliothis zea ; Hymenoptera ; Trichogrammatidae ; Trichogramma pretiosum ; egg parasitoid ; sex pheromone ; kairomone ; host-community location ; olfactometer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé Des expériences menées en olfactométrie avec le parasite oophage Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) et son hôte, Heliothis zea (Boddie) (Lepidoptera: Noctuidae) donnent les résultats suivants. La présence de la phéromone sexuelle de l'hôte réduit de façon significative le nombre de passages entre les champs odorisés. De mème, les parasites visitent plus fréquemment le champ qui dispense l'odeur de la femelle en appel que le champ témoin placé à l'opposé. Par ailleurs, le temps passé dans le champ qui contient la phéromone sexuelle émise par les femelles vierges en appel est significativement supérieur à la durée de visite des champs témoins. Si l'on utilise comme source d'odeur des femelles vierges qui ne sont pas en appel, la réponse est inversée, les parasites sont alors repoussés par l'odeur de ces papillons et le nombre de visites est distribué de façon aléatoire entre les quatre champs. Ces résultats sont discutés dans le contexte de l'écologie du comportement de recherche chez les parasites oophages.
    Notes: Abstract This paper presents results of olfactometer experiments with the egg parasitoid Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) and its host the corn earworm moth, Heliothis zea (Boddie) (Lepidoptera: Noctuidae). The sex pheromone of the host significantly reduced the total number of border crossings between odour fields in the olfactometer. Also, female parasitoids made significantly more visits to the calling moth odour field than to the opposite control field in the olfactometer. Further, the wasps spent significantly more time in the olfactometer field containing the sex pheromone released by calling virgin moths, than in control fields. If non-calling virgin moths were used as odour source, the response was reversed and wasps were repelled by the odour of the moths, and the numbers of visits were evenly distributed over the four flow fields. These results are discussed in the context of foraging ecology of egg parasitoids.
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  • 11
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    Entomologia experimentalis et applicata 49 (1988), S. 25-36 
    ISSN: 1570-7458
    Keywords: behavioural thresholds ; Lepidoptera ; mating disruption ; pheromone blends ; pheromonal communication
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract It is widely assumed that a blend of pheromone components, that is qualitatively and quantitatively similar to the natural sex attractant, is the most effective mating disruptant for moths. However, the literature contains only limited evidence supporting this assumption. The authors discuss the importance of comparing the relative effectiveness of complete and incomplete pheromone blends when evaluating the potential of mating disruption for controlling pest moths.
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  • 12
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    Entomologia experimentalis et applicata 49 (1988), S. 37-42 
    ISSN: 1570-7458
    Keywords: Lepidoptera ; Cydia nigricana ; pea moth ; pheromone ; sex-attractant ; orientation ; anemotaxis ; substrate ; contamination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The close-range orientation behaviour of male pea moths, Cydia nigricana (F.) (Lepidoptera: Tortricidae), to a substrate contaminated with synthetic sex pheromone was studied in the field. The substrate was a sheet of polypropylene ‘grass’ on a 1 m diam arena, on the upwind edge of which a pheromone trap had been placed previously for 1 h. After removal of the trap, moths continued to be attracted to the arena and to the vacated trap position. Video-recorded tracks showed that the moths behaved anemotactically whilst on the arena. When the arena was revolved so that the vacated trap position was on the downwind edge, moths continued to fly upwind on the arena, even though they were flying away from the original trap position and down a concentration gradient.
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  • 13
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    Entomologia experimentalis et applicata 46 (1988), S. 227-232 
    ISSN: 1570-7458
    Keywords: tri-trophic level interactions ; nicotine ; alkaloid ; Hyposoter annulipes ; Hymenoptera ; Ichneumonidae ; fall armyworm ; Spodoptera frugiperda ; Lepidoptera ; Noctuidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé Des quantités croissantes de nicotine dans l'alimentation ont prolongé la durée du développement des chenilles saines, bien que l'effet ait chuté aux concentrations les plus élevées. Le sexe de la noctuelle n'a pas eu d'effet sur la durée du développement ou l'action de la nicotine. L'influence de la nicotine sur le poids des chrysalides est inhabituel, en ce sens que les chrysalides les plus lourdes ont été obtenues aux concentrations moyennes. Des hypothèses sont proposés sur l'origine de ce phénomène. La mortalité et la durée de développement de H. annulipes ont augmenté et le poids des adultes a diminué quand la concentration de l'aliment de l'hôte en nicotine s'est élevée. L'effet différente de la nicotine sur des générations successives a pu provenir de modifications de la toxicité de la nicotine en fonction de changements dans la qualité de l'aliment. Quoi qu'il en soit, l'augmentation de la concentration de la nicotine dans l'alimentation de l'hôte a eu un effet négatif cohérent sur la valeur adaptative de H. annulipes.
    Notes: Abstract Experiments were conducted to determine the influence of nicotine (at a range of concentrations) in the food of an herbivorous host on the development, size and survival of its parasitoid. Fall armyworms, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) were reared on diets of 0, 0.025, 0.050 and 0.075% nicotine and exposed to parasitism by Hyposoter annulipes (Hymenoptera: Ichneumonidae). As nicotine concentration increased parasitoid mortality and development time increased and adult weight decreased. Development time, pupal weight and survival were recorded for unparasitized armyworms. Unparasitized fall armyworms showed lengthened development and higher mortality but pupal weights were greatest at intermediate nicotine concentrations.
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  • 14
    ISSN: 1570-7458
    Keywords: Lepidoptera ; Arctiidae ; Sex Pheronome ; Behaviour ; Electroantennography ; Physico-chemistry ; (Z,Z)-3,6-Cis-9S,10R-epoxyheneicosadiene ; (Z,Z)-3,6-Cis-9,10-epoxyeicosadiene ; (Z,Z,Z)-3,6,9-heneicosatriene ; Lépidoptère ; Arctiidae ; Phéromone sexuelle ; Comportement ; Electroantennographie ; Physicochimie ; Epoxy-9S,10R-(Cis) hénéicosadiène-3Z,6Z ; Epoxy-9,10-(Cis) éicosadiène-3Z,6Z ; Hénéicosatriène-3Z,6Z,9Z
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Abstract The hexanic extracts from pheronomal glands of T. jacobaeae virgin females have been studied. Gas-chromatographic and mass-spectrometric analyses of the main component (no 1) (98%) in combination with behavioral and electrophysiological bioassays allowed us to determine its structure and absolue configuration: (Z,Z)-3,6-Cis-(S,R)9,10-epoxyheneicosadiene previously described in other Arctiid moths. A minor constituent (no 2) (1.5%) was identified as (Z,Z)-3,6-Cis-(S,R)9,10-epoxyeicosadiene by comparison with synthetic compound. This structure is a new one for a lepidoptera sex pheromone. The third component (no 3) of the same extracts has the same physico-chemical data as those of a previously reported constituent of another Arctiid moth: (Z,Z,Z)-3,6,9 heneicosatriene.
    Notes: Abstract Les analyses physico-chimiques d'extraits hexaniques de glandes à phéromone de femelles vierges de T. jacobaeae, associées à des études du comportement sexuel et à l'électroantennographie, ont permis d'identifier le composé majoritaire (98%) comme étant l'époxy-9S,10R-(Cis)-hénéicosadiène-3Z,6Z (no 1) et de déterminer sa configuration absolue. Les analogies entre les spectres du composé no 2 (1,5%) et ceux de l'époxy-9S,10R éicosadiène-3Z,6Z de synthèse nous conduisent à proposer cette structure pour ce constituant minoritaire. Le troisième produit (0,5%) possède les caractéristiques physico-chimiques de l'hénéicosatriène-3Z,6Z,9Z (no 3). Les produits 1 et 3 ont déjà été identifiés comme constituants de phéromones d'Arctiidae tandis que le produit 2 est décrit ici pour la première fois dans une sécrétion phéromonale de Lépidoptère.
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  • 15
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    Entomologia experimentalis et applicata 47 (1988), S. 289-295 
    ISSN: 1570-7458
    Keywords: competition ; multiparasitization ; parasitoid ; physical attack ; Trieces tricarinatus ; Triclistus yponomeutae ; Hymenoptera ; Ichneumonidae ; Yponomeuta vigintipunctatus ; Lepidoptera ; Yponomeutidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé La compétition entre les deux ichneumonides endoparasitoïdes solitaires Trieces tricarinatus Grav. et Triclistus yponomeutae Aeschl. a été examinée en élevant et disséquant des Yponomeuta vigintipunctatus Retz. attaqués le même jour par les deux parasitoïdes. Les résultats des dissections des hôtes multiattaqués ont été comparés à ceux des hôtes attaqués par un seul parasite, pour séparer la mortalité ou l'absence de parasitoïde provoquées par la compétition à celles dues à d'autres facteurs. On a constaté qu'un seul parasite était capable d'achever son développement. Dès que l'hôte était nymphosé et que les deux parasitoïdes étaient au premier stade larvaire, une des larves tuait sa compétitrice. Pour une fraction importante des larves éliminées, il a été possible de montrer qu'elles avaient été tuées par une aggression physique, pour les autres ce mode d'élimination était vraisemblable. L'espèce de parasitoïde qui survit dépend du nombre de jours entre la ponte des ichneumonides et la nymphose de l'hôte. Ce délai détermine le degré de développment des parasitoïdes et le moment réel de la compétition. Probablement, T. tricarinatus est le seul à survivre lorsque la nymphose de l'hôte a lieu avant l'éclosion des oeufs de T. yponomeutae.
    Notes: Abstract Competition between the solitary endoparasitoids Trieces tricarinatus (Gravenhorst) and Triclistus yponomeutae Aeschlimann (Hymenoptera: Ichneumonidae) results in the survival of one or the other of them. Once the host, Yponomeuta vigintipunctatus (Retzius) (Lepidoptera: Yponomeutidae) has pupated and both parasitoids have completed their development to first instar larvae, one of the parasitoid larvae kills the other. Which of the parasitoids survives depends on the number of days between parasitization and pupation. As a result of their type of development, this period determines the extent of development of the parasitoids at the moment of actual competition. Apparently, T. tricarinatus survives only if pupation of the host occurs before egg hatching of T. yponomeutae.
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  • 16
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    Entomologia experimentalis et applicata 48 (1988), S. 149-156 
    ISSN: 1570-7458
    Keywords: Formamidines ; chlordimeform ; Lepidoptera ; behaviour ; starvation ; survival ; development ; sublethal control
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé Les chenilles de troisième et cinquième stades de P. brassicae L. ont reçu une application superficielle de chlordiméforme, insecticide à la formamidine. Les doses inférieures à 335 μg/g ont été sublétales, provoquant plusieurs formes d'excitation. Bien que leur comportement soit redevenu normal en 24 heures, les troisièmes stades traités ont eu leur développement retardé et une mortalité accrue. Le traitement des chenilles plus âgées a eu moins d'effets. Une relation est suggérée entre ces observations et le régime alimentaire de cet insecte; une réduction de l'alimentation, plus importante chez les chenilles de troisième que de cinquième stade de P. brassicae, accompagne le début des altérations du comportement provoquées par le chlordiméforme. La discussion porte sur le mécanisme de contrôle sublétal du chlordiméforme, impliquant des effects immédiats et retardés.
    Notes: Abstract Larvae of the large cabbage white butterfly, Pieris brassicae L. are important pests of cruciferous crops. Third and fifth instars were treated topically with sublethal doses of the formamidine pesticide chlordimeform. A number of excitable actions were induced but they did not persist beyond 24 hours. Following the initial period, however, subsequent development was delayed and mortality increased, particularly when third instars were treated. Dosing fifth-instar larvae caused few further deaths. A link is suggested between these results and the nutritional status of the insects, and they are discussed in terms of how they might contribute towards control.
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  • 17
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    Entomologia experimentalis et applicata 48 (1988), S. 141-147 
    ISSN: 1570-7458
    Keywords: Lepidoptera ; aggregation behaviour ; feeding ; chlordimeform ; crop protection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé Un des effets sublétaux du chlordiméforme, insecticide formamidine, est une réduction de la prise de nourriture, par suite de l'altération du comportement. Celle-ci implique une action stimulant l'activité locomotrice du quatrième stade de P. brassicae L., moins sensible aux effets sur l'alimentation. Le but de ce travail est d'examiner comment le chlordiméforme agit sur le comportement des chenilles du second stade. Des chenilles sur des feuilles trempées dans le chlordiméforme (10-6 à 10-2) sont vite excitées, leur déplacements s'accélèrent et les groupements formés sont tous instables, l'alimentation y étant généralement éphémère. L'excitation se réduit au bout de 24 heures, le groupements se reforment, et l'alimentation reprend, bien que pour les concentrations ≥10-4 M, les chenilles aient été encore dispersées entre 24 et 30 heures, au moment où elles commençaient à s'alimenter sur les résidus de chlordiméforme. La perturbation de la concentration des chenilles sur des disques témoins a montré une relation directe entre la taille du groupe et le taux de croissance larvaire. Nous en avons conclu que chez les espèces de lépidoptères qui consomment groupées, une interaction avec l'agrégation larvaire contribue significativement à l'effet du chlordiméforme sur l'alimentation. La discussion porte sur les conséquences pour la croissance et la survie larvaire, particulièrement en ce qui concerne l'installation des chenilles néonates.
    Notes: Abstract The behavioural basis for the reduction in feeding caused by the formamidine pesticide chlordimeform was investigated in second-instar larvae of the large cabbage white butterfly, Pieris brassicae L. Normally, these caterpillars feed communally. On chlordimeform-dipped leaves (10-6 M–10-2 M) they rapidly became excited, locomotion increased and only unstable aggregations formed in which any feeding was usually transient. Over 24 h excitation declined, aggregations re-formed and feeding was resumed. However, between 24 and 30 h, on leaves treated with chlordimeform solutions of 10-4 M or greater, larvae dispersed again. By altering the density of larvae on control discs a direct link was revealed between clump size and larval growth rates. It is concluded that, in species which feed gregariously, interference with larval aggregation contributes significantly to chlordimeform's effects on feeding and its involvement in a sublethal control mechanism in the field is discussed.
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  • 18
    ISSN: 1432-0983
    Keywords: Wheat chloroplast DNA ; Repeated sequences ; Ribosomal protein genes ; Evolution
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    Topics: Biology
    Notes: Summary Some dispersed repeated sequences and their flanking regions from wheat and maize ctDNAs have been characterized. Two sets of wheat ctDNA repeats were found to be the chloroplast ribosomal protein genesrpl2 andrpl23, plus nonfunctional segments of them, designatedrpl2′ andrpl23′. Pairwise comparisons were made between the wheatrp123 andrpl23′, and the maizerp123′ sequences. The precise patterns of homology suggest that the divergence of the wheat and maize nonfunctional (rpl23′) sequences is being retarded by nonreciprocal recombination, biased by selection for individuals with functional (rpl23) sequences. The implied involvement of these sequences in mechanisms of homologous recombination, and therefore in the creation and spread of new ctDNA variants, is discussed.
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  • 19
    ISSN: 1432-0983
    Keywords: Physarum polycephalum ; rRNA ; Sequence ; Evolution
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    Topics: Biology
    Notes: Summary The nucleotide sequence of the Physarum polycephalum small subunit ribosomal RNA (SSU rRNA) gene has been determined. Sequence data indicate that the mature 19S SSU rRNA is 1,964 nucleotides long. A complete secondary structure model for P. polycephalum SSU rRNA has been constructed on the basis of the Escherichia coli 16S rRNA model and data from comparative analyses of 28 different eukaryotic sequences. A “four-helix” model is presented for the central domain variable region. This model can be applied both to vertebrate and most lower eukaryotic SSU rRNAs. The increased size of P. polycephalum SSU rRNA relative to the smaller SSU rRNAs from such other lower eukaryotes, as Dictyostelium, Tetrahymena or Saccharomyces is due mainly to three G+C-rich insertions found in two regions known to be of variable length in eukaryotes. In a phylogenetic tree constructed from pairwise comparisons of eukaryotic SSU rRNA sequences, the acellular myxomycete P. polycephalum is seen to diverge before the appearance of the cellular mycomycete Dictyostelium discoideum.
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  • 20
    ISSN: 1432-0983
    Keywords: Evolution ; Sequence comparison ; RUBISCO ; Transit peptide
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    Notes: Summary We have isolated and characterized a full-length cDNA clone encoding the precursor of the small subunit (pSU) of ribulose-1,5-bisphosphate carboxylase/oxygenase (RUBISCO) from the green alga, Chlamydomonas moewusii. Comparison with the C. reinhardtii rbcS1 gene sequence reveals that both small subunit (SS) coding regions are 75% homologous and that their predicted mature polypeptide chains are each composed of 140 amino acids. In contrast, their transit peptides appear to be divergent. We also show that transcription of the C. moewusii rbcS gene(s) which generates a 1,230 and a 930 base mRNA species are light-stimulated/or accumulated during the light period of the cell cycle. Finally, the SS polypeptide sequences of fifteen different photosynthetic organisms are compared; this analysis reveals at least five well-conserved polypeptide domains.
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  • 21
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    Journal of molecular evolution 28 (1988), S. 98-112 
    ISSN: 1432-1432
    Keywords: rRNA ; Evolution ; Sequence comparison ; Parsimony ; Bootstrap
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Sequences of small subunit (SSU) and large subunit (LSU) ribosomal RNA genes from archaebacteria, eubacteria, and the nucleus, chloroplasts, and mitochondria of eukaryotes have been compared in order to identify the most conservative positions. Aligned sets of these positions for both SSU and LSU rRNA have been used to generate tree diagrams relating the source organisms/organelles. Branching patterns were evaluated using the statistical bootstrapping technique. The resulting SSU and LSU trees are remarkably congruent and show a high degree of similarity with those based on alternative data sets and/or generated by different techniques. In addition to providing insights into the evolution of prokaryotic and eukaryotic (nuclear) lineages, the analysis reported here provides, for the first time, an extensive phylogeny of the mitochondrial lineage.
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  • 22
    ISSN: 1432-1432
    Keywords: Aspergillus nidulans ; 5S rRNA ; Pseudogenes ; Evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary AllAspergillus nidulans 5S rRNA pseudogenes known so far are the result of integration of an approx. 0.2-kbp-long DNA sequence into the 5S rRNA genes. This sequence, called block C, is present in at least five copies in theA. nidulans genome and seems to be associated either with 5S rRNA genes or pseudogenes. In contrast to the 78% sequence conservation of the C-block in pseudogenes, the truncated 5′ halves of the pseudogenes are very highly conserved (96.9–100%). We postulate that the 5S rRNA pseudogenes are still a subject of concerted evolution. The C-block sequence shows similarity to the switch region of the mouse heavy chain immunoglobulin gene. A characteristic motif GGGTGAG is repeated several times in both sequences; the sequence conservation is 63%.
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  • 23
    ISSN: 1432-1432
    Keywords: Tropomyosin ; Differential splicing ; Evolution ; Isochore ; Codon usage ; Sequence convergence ; Functional constraints
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have cloned and determined the nucleotide sequence of a complementary DNA (cDNA) encoded by a newly isolated human tropomyosin gene and expressed in liver. Using the leastsquare method of Fitch and Margoliash, we investigated the nucleotide divergences of this sequence and those published in the literature, which allowed us to clarify the classification and evolution of the tropomyosin genes expressed in vertebrates. Tropomyosin undergoes alternative splicing on three of its nine exons. Analysis of the exons not involved in differential splicing showed that the four human tropomyosin genes resulted from a duplication that probably occurred early, at the time of the amphibian radiation. The study of the sequences obtained from rat and chicken allowed a classification of these genes as one of the types identified for humans. The divergence of exons 6 and 9 indicates that functional pressure was exerted on these sequences, probably by an interaction with proteins in skeletal muscle and perhaps also in smooth muscle; such a constraint was not detected in the sequences obtained from nonmuscle cells. These results have led us to postulate the existence of a protein in smooth muscle that may be the counterpart of skeletal muscle troponin. We show that different kinds of functional pressure were exerted on a single gene, resulting in different evolutionary rates and different convergences in some regions of the same molecule. Codon usage analysis indicates that there is no strict relationship between tissue types (and hence the tRNA precursor pool) and codon usage. G+C content is characteristic of a gene and does not change significantly during evolution. These results are in good agreement with an isochore composition of the genome, and thus suggest a similar chromosomal environment in chicken, rat, and human.
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  • 24
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    Journal of molecular evolution 27 (1988), S. 291-297 
    ISSN: 1432-1432
    Keywords: P1 P2 protamines ; Evolution ; Regulatory sequence ; Primordial sequence ; Similarity ; Alignment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary With the recent availability of the primary structural data for the trout, bovine, and mouse protamine genes, a detailed comparison of their structures has been made. This has revealed extensive conservation of potentially biologically significant regions. An inverse correlation is apparent between gene copy number and the number of sequence-distinct protamines synthesized with the number of CP-box-like (CCYPCCC) putative transcription modulating sequences situated 5′ to these genes. A common nucleotide sequence 5′ to the CP-box-like putative transcription modulating sequence(s) at the end of a common region has been identified. It is postulated that this is the testis-specific protamine P1 transcription regulator sequence. Evidence based on sequence similarity is also provided for the existence of a primordial protamine gene and a scheme for the evolution of vertebrate protamine genes is proposed.
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  • 25
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    Journal of molecular evolution 27 (1988), S. 17-28 
    ISSN: 1432-1432
    Keywords: Actin genes ; Evolution ; 5′ and 3′ untranslated regions
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    Topics: Biology
    Notes: Summary We have sequenced the coding and leader regions, as well as part of the 3′ untranslated region, of aXenopus borealis type 1 cytoskeletal actin gene [defined according to the arrangement of acidic residues at the N-terminus; Vandekerckhove et al. (1981) J Mol Biol 152:413–426]. The encoded amino acid sequence is the same as the avian and mammalian β (type 1) cytoskeletal actins, except for an isoleucine at position 10 (as found in the mammalian γ cytoskeletal actins), and an extra amino acid, alanine, after the N-terminal methionine. Five introns were found, in the same positions as those of the rat and chicken β-actin genes. The 5′ and 3′ untranslated regions resemble those of the human γ (type 8) cytoskeletal actin gene more closely than the mammalian β genes. Primer extension showed that this type 1 gene is transcribed in ovary and tadpole. Sequencing of primer extension products demonstrated two additional mRNA species inX. borealis, encoding type 7 and 8 isoforms. This contrasts with the closely related speciesXenopus laevis, where type 4, 5, and 8 isoforms have been found. The type 7 isoform has not previously been found in any other species. The mRNAs of theX. borealis type 1 and 8 andX. laevis type 5 and 8 isoforms contain highly homologous leaders. TheX. borealis type 7 mRNA has no leader homology with the other mRNA species and, unlike them, has no extra N-terminal alanine codon. The evolutionary implications of these data are discussed.
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  • 26
    ISSN: 1432-1432
    Keywords: Histone genes ; Sea stars ; Echinoderms ; Evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The arrangement of core histone genes and their transcriptional polarity has been determined for three species of sea stars (Pisaster ochraceus, P. brevispinus, andDermasterias imbricata) representing two orders which diverged over 500 million years ago. Each species has approximately 500 core histone cluster repeats per haploid genome. The close phylogenetic relationship between thePisaster species is evident from the correspondence of restriction sites in the repeat element, identical arrangement of core histones, and high degree of sequence homology in both the coding and spacer regions of the H3 gene. TheDermasterias repeat has the same gene order and transcriptional polarity of core histones, but its restriction map is significantly different. Moreover, theDermasterias H3 gene has the same amino acid sequence, but in comparison toPisaster nucleotide sequences, shows a high level of silent substitutions. Analyses of the nucleotide sequence of the 5′ and 3′ regions surrounding the H3 gene from each species demonstrate the presence of appropriately spaced consensus and processing signal segments. The 3′ spacer segment of theDermasterias H4 gene contains an unusual, threefold tandemly repeated, 21-nucleotide, AT-rich sequence. No similar sequence is seen in theP. brevispinus H4 3′ region, but these two species show a striking regularity of distribution of five different homologous oligomers in the 3′ spacer.
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  • 27
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    Journal of molecular evolution 27 (1988), S. 102-108 
    ISSN: 1432-1432
    Keywords: Hemopexin ; Evolution ; Gene structure ; Recombination ; Sequence homology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The human hemopexin gene was isolated and its structure determined. The gene spans approximately 12 kb and is interrupted by nine introns. When the intron/exon pattern was examined with respect to the polypeptide segments they encode, a direct correspondence between exons and the 10 repeating units in the protein was observed. The introns are not randomly placed; they fall in the middle of the region of amino acid sequence homology in strikingly similar locations in 6 of the 10 units and in a symmetrical position in the two halves of the coding sequence. These features strongly support the hypothesis that the gene evolved through intron-mediated duplications of a primordial sequence to a five-exon cluster. A more recent gene duplication led to the present-day gene organization.
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  • 28
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    Sexual plant reproduction 1 (1988), S. 208-216 
    ISSN: 1432-2145
    Keywords: Megagametophyte ; Synergids ; Brassica campestris ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary In Brassica campestris, both synergids of the ovule degenerate before the arrival of the pollen tube. Synergid degeneration does not depend on pollination. At the non-degenerated stage, the synergids are completely filled with a complexly organized cytoplasm containing numerous mitochondria with many cristae, a large number of dictyosomes with many associated vesicles, and a very extensive rough endoplasmic reticulum. The degenerative changes that occur in the cytoplasm of the synergids are characterized by a loss of visibility of the membranes of the endoplasmic reticulum and the simultaneous formation of dense deposits on the surrounding membranes of the mitochondria. Locally, the plasma membranes of the synergids disappear, and some ground plasma of the synergids penetrates into the space between the plasma membranes of the egg cell and the central cell.
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  • 29
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    Archives of microbiology 150 (1988), S. 56-60 
    ISSN: 1432-072X
    Keywords: Fumarate reduction ; Quinones ; Rhodospirillaceae ; Phototrophic bacteria ; Evolution ; Taxonomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Nineteen established and one undesignated species of the Rhodospirillaceae were examined for fumarate reduction in connection with their quinone systems. The fumarate reductase activity with reduced methyl viologen (MVH) or FMNH2 as electron donor was found in membrane (chromatophore) preparations from phototrophically grown cells of all species containing menaquinone (MK) and/or rhodoquinone. The species having ubiquinone as the sole quinone contained no fumarate reductase activity, except some Rhodobacter species showing the FMNH2-dependent activity. The MVH-fumarate reductase activity of the MK-type species was not inhibited by Triton X-100 or acetone treatment, suggesting the presence of a fumarate reductase reacting directly with MVH, while such an enzyme was absent in the MK-lacking strains, with few exceptions. The FMNH2-fumarate reduction system was abolished by a detergent or acetone extraction in all bacteria but differed much among species with different quinone types as to the response to respiratory inhibitors. These differences in fumarate-reducing properties and quinone systems among the phototrophic bacteria are discussed from evolutionary and taxonomic viewpoints.
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  • 30
    ISSN: 1432-072X
    Keywords: Eubacteria ; Evolution ; Extreme thermophile ; Thermotoga
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    Topics: Biology
    Notes: Abstract A second species of the extremely thermophilic, eubacterial genus Thermotoga is described as clearly distinguished from the type species Thermotoga maritima by physiological and phylogenetic criteria. It is named Thermotoga neapolitana.
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  • 31
    ISSN: 1432-2285
    Keywords: Nuclear crystalloid inclusions ; Olea europaea ; Cytochemistry ; Ultrastructure ; Glycoprotein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The nuclei of mesophyll cells of olive trees contain numerous sizeable crystalloid inclusions. Cytochemical examination using epoxy resin-embedded, semithin-sectioned tissue indicated the presence of proteins and oligoor polysaccharides in these inclusions. Their electron microscopical analysis revealed a crystalline substructure consisting of intersected subunits of high order. The spacing of the lattice fibrils and the angles of intersection were determined and used to establish a model of the unit cell of crystallization. It is suggested that the nuclear crystalloids of olive trees consist of glycoprotein molecules. They differ from the intranuclear crystalloids observed in other species predominantly in the high density of their subunit arrangement.
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  • 32
    ISSN: 1573-1561
    Keywords: Sex pheromone ; Lepidoptera ; Noctuidae ; Pseudoplusia includens ; Trichoplusia ni ; multicomponent pheromone blends ; sustained-flight tunnel ; behavioral thresholds
    Source: Springer Online Journal Archives 1860-2000
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    Notes: Abstract The response of male cabbage looper (CL) and soybean iooper (SBL) moths was observed in the flight tunnel and measured in field tests to the six-component CL pheromone, the five-component SBL pheromone, and toZ7–12: OAc, the major component common to each pheromone. In both the flight tunnel and the field, male CL exhibited significantly greater levels of response to their six-component blend than toZ7–12: OAc alone. A low level of cross-attraction of male CL to the SBL pheromone was observed in both the flight tunnel and the field, but it was quantitatively and qualitatively similar to their response toZ7–12: OAc alone. Thus the minor components of the SBL blend did not appear to disrupt the flight behavior of male CL. With respect to SBL, in the flight tunnel males also exhibited a greater level of response to the five-component blend compared toZ7–12: OAc, but in the field their response was not significantly different to either treatment. There was also a low level of cross-attraction of male SBL to the CL blend, but this appeared to involve a significant arrestment effect on the upwind flight of males, as well as a difference in male sensitivity to the blend of components compared withZ7–12: OAc alone. The observed arrestment effect may have been due to male perception of one or more minor components of the CL pheromone. The results show that the multicomponent pheromones of these species function effectively as specific mating signals and that discrimination of odor quality by male moths can occur as the result of minor components affecting male sensitivity or their upwind flight response to the pheromone.
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  • 33
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    Journal of chemical ecology 14 (1988), S. 319-334 
    ISSN: 1573-1561
    Keywords: Iridoid glycoside ; Junonia coenia ; Lymantria dispar ; Lepidoptera ; Nymphalidae ; Lymantriidae ; induction ; insect-plant interaction ; generalist herbivore ; specialist herbivore
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract We examined the effects of a set of four biosynthetically related iridoid glycosides, aucubin, catalpol, loganin, and asperuloside, on larvae of a generalist,Lymantria dispar (Lymantriidae), the gypsy moth, and an adapted specialist, the buckeye,Junonia coenia (Nymphalidae). In general,L. dispar grew and survived significantly less well on artificial diets containing iridoid glycoside, compared to a control diet without iridoid glycosides. In choice tests, previous exposure to a diet containing iridoid glycosides caused larvae subsequently to prefer iridoid glycoside-containing diets even though they were detrimental to growth and survival. In contrast,J coenia larvae grew and survived better on diets with aucubin and catalpol, the two iridoid glycosides found in the host plantPlantago lanceolata (Plantaginaceae), than on diets with no iridoid glycoside or with loganin and asperuloside. The results of choice tests of diets with and without iridoid glycosides and between diets with different iridoid glycosides reflected these differences as well. These results are discussed in terms of (1) differences between generalists and specialists in their response to qualitative variation in plant allelochemical content, (2) the induction of feeding preferences, and (3) the evolution of qualitative allelochemical variation as a plant defense.
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  • 34
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    Journal of chemical ecology 14 (1988), S. 2019-2031 
    ISSN: 1573-1561
    Keywords: Lepidoptera ; desaturases ; pheromone ; enzymes ; detergents ; fatty acids ; biosynthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Pheromone components for many lepidopteran species are produced by the use of unique chain-shortening and Δ9, Δ10, and Δ11 desaturase systems. Correlations in the Tortricidae indicate that the pheromone components derived from Δ9 and Δ01 desaturases are found in the more primitive species (those possessing morphological plesiomorphies). The precise blend ofZ andE acetates in a number of species is regulated in the final reduction sequence from acyl intermediates. Preliminary research has been conducted on the characterization of the various desaturase enzymes used and on the important blend regulating sequence. Initial purification work on the Δ11 desaturase enzyme found in the cabbage looper moth is reported.
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  • 35
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    Journal of chemical ecology 14 (1988), S. 2063-2069 
    ISSN: 1573-1561
    Keywords: Heliothis zea ; Heliothis phloxiphaga ; Lepidoptera ; Noctuidae ; sex pheromone ; neuropeptide hormone ; mating ; host plant factors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Sex pheromone production and release in females ofHeliothis species exhibit a diel periodicity. Phermone production is controlled by a hormone, the pheromone biosynthesis activating neuropeptide (PBAN). Release of PBAN to activate pheromone production follows a circadian rhythm. InH. zea females, mating terminates pheromone production. An unidentified hemolymph-borne factor is transferred from the male to the female during mating. It is speculated that this factor interacts with the release mechanism of PBAN to prevent further production of the pheromone following mating. Wild females ofH. phloxiphaga (reared from larvae collected in the field) did not produce or release the sex pheromone unless kept in association with the host plant. Pheromone production could be induced in these females by the injection of PBAN. It is suggested that a signal from the host plant is essential to trigger the release of PBAN to induce pheromone production.
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  • 36
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    Journal of chemical ecology 14 (1988), S. 2131-2145 
    ISSN: 1573-1561
    Keywords: Sex pheromone biosynthesis ; cuticle ; alcohol oxidase ; alcohol ; aldehyde ; Heliothis zea ; Lepidoptera ; Noctuidae ; enzyme
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Biosynthesis of the aldehydic sex pheromone components released by females ofHeliothis zea was found to be catalyzed by primary alcohol oxidases residing in the cuticle that covers the glands. Activity, as indicated by conversion of primary alcohol to aldehyde, was as high in cell-free cuticle as it was in intact pheromone glands. Studies indicated that some activity was associated with the surface of the epicuticle and could be removed, into buffer, by sonication. However, the majority of activity lies within the inner epicuticle and exo- and endocuticular layers. The oxidase was not functional in pharate pupae that did not have mature adult cuticle but became functional just prior to adult emergence. The enzyme in individual glands was saturated at alcohol concentrations above 100 n. moles. Nonionic detergents did not affect the activity of the oxidase in the cuticle but treatment with either 7 M urea or 1% SDS resulted in total loss of activity. Studies on the effect of pH indicated an optimum at 6.4; however, activity was high throughout the range of 5–9. The oxidase was functional in both dichloromethane and hexane, suggesting that this enzyme system may have applications for organic synthesis of aldehydes.
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  • 37
    ISSN: 1573-1561
    Keywords: β-Carboline alkaloids ; harman ; harmins ; Spodoptera exigua (Hubner) ; beet armyworm ; antifeedant ; Lepidoptera ; Noctuidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract β-Carboline alkaloids are found worldwide in many plant families. Harman, harmine, and other simple β-carboline alkaloids were tested for activity against a generalist phytophagous insect, the beet army worm [Spodoptera exigua (Hubner)]. Chronic dietary exposure tests (neonate to pupa) reveal potent antifeedant and possible toxic effects. Acute dietary exposure tests on fifth-instar larvae also demonstrate antifeedant activity.
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  • 38
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    Journal of chemical ecology 14 (1988), S. 537-547 
    ISSN: 1573-1561
    Keywords: Lymantria monacha ; Lepidoptera ; Lymantriidae ; pheromone communication ; mating disruption ; disparlure ; slow-release formulations
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The feasibility of using the synthetic sex pheromone, disparlure, as a mating confusant of the nun moth (Lymantria monacha L.) was investigated on wild populations occurring in outbreak proportions in Poland and in low density in Czechoslovakia. The size of experimental plots ranged from 1 to 12 hectares. The amounts of pheromone applied were 10 or 20 g/hectare. Three types of slow-release formulations of a racemic mixture of disparlure were tested: (1) a spray formulation with latex as a carrier, (2) a tubing of natural rubber, and (3) sawdust of a porous material used for making tips of fiber-tip pens. All three pheromone formulations prevented significant numbers (98.6–100% in the low density situation, 90–96.2% during the outbreak) of the males from locating a discrete source of pheromone (a trap containing synthetic pheromone or a female) during the whole flight period, indicating long-lasting efficiency of the formulations.
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  • 39
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    Journal of chemical ecology 14 (1988), S. 797-813 
    ISSN: 1573-1561
    Keywords: Codling moth ; Laspeyresia pomonella ; Lepidoptera ; Tortrici-dae ; codlemone ; sex pheromone ; parapheromones ; inhibitors ; olefinic alcohols ; wind tunnel ; orientation flight
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The primary pheromone (E,E)-8,10-dodecadien-1-ol (I, codle-mone), 11 further alcohols, and binary blends of both were evaluated for attractiveness as defined by the percentage ofL. pomonella males showing oriented upwind flight terminated by landing at the source within 10 min after release. Sources of I were attractive from 10−5 μg to 101 μg, with approx. 70% males responding at 10−3−10−1 μg. Most other alcohols also showed attractiveness, but the dose-response curves differed greatly with respect to the range of effective lure doses as well as the maximum response level reached at any dose. (E,E)-7,9-Undecadien-1-ol (III) revealed a dose-response curve similar in shape to I but shifted towards higher concentrations. (E,E)-8,10-Tridecadien-1-ol (II) and (E)-8,10-undecadien-1-ol (IV) exhibited threshold values of 10−5 μg (same as for I) and were effective over, respectively, seven and nine decades of source load, but they did not reach a response level of 40% at any test amount. (E)-9,11-Dodecadien-1-ol (VI) and the monoenes (E)-8-, (E)-10-, and (Z)-10-dodecen-1-ol (VIII-X) showed weak attractivity restricted to one to three test doses. Upwind approaches that broke off a few centimeters from the source were rarely seen in tests with I but frequently occurred with some of the analogs. When combined with 10−3 μg of I, all alcohol analogs showed “inhibitory” properties, although the amounts required to obtain a significant lowering of response differed by up to 105-fold. This amount was the lowest (10−4 μg) for the positional isomer VI, and the highest (101 μg) for undecan-1-ol (XI) and dodecan-1-ol (XII). With some mixtures, the presence of the inhibitor appeared to cause an alteration in landing behavior. No synergistic effects were seen in these tests. The results are briefly considered with respect to the sensory perception of the test stimuli and the involvement of minor components in the female pheromone blend.
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  • 40
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    Journal of chemical ecology 14 (1988), S. 815-824 
    ISSN: 1573-1561
    Keywords: Trail pheromones ; trail marking ; 5β-cholestane-3,24-dione ; tent caterpillars ; Malacosoma nuestria L. ; Lepidoptera ; Lasiocampidae ; recruitment ; leader-follower behavior
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Chemical trail marking and following by gregarious caterpillars,Malacosoma neustria L. (Lepidoptera: Lasiocampidae), was studied in the laboratory. As in other species ofMalacosoma, larvae deposit a trail pheromone from a sternal secretory site when searching the host for food. Larvae in the vanguard of foraging columns establish chemical trails as they explore new territory. Marking behavior diminishes as successive unfed foragers utilize the trail. These exploratory trails are subsequently overmarked by fed larvae returning to the tent. Other foragers follow the trails of fed larvae in preference to trails of unfed larvae. Thus, like the eastern tent caterpillar,M. americanum, successful foragers ofM. neustria recruit colony-mates to feeding sites. The chemical activity of both recruitment and exploratory trails degrades slowly, suggesting that the trail pheromone ofM. neustria is a nonvolatile substance. Caterpillars ofM. neustria readily follow the nonvolatile trail pheromone which has been identified fromM. americanum, 5β-cholestane-3,24-dione.
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  • 41
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    Journal of chemical ecology 14 (1988), S. 903-915 
    ISSN: 1573-1561
    Keywords: pheromone ; Lepidoptera ; Tortricidae ; Cydia pomonella ; biosynthesis ; palmitic acid ; (E)-9-dodecenoic acid ; (E,E)-8,10-dodecadienol ; E9 desaturation ; capillary gas chromatography ; deuterium ; labeled precursors
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Sex pheromone biosynthesis in the codling mothCydia pomonella (Lepidoptera; Tortricidae) was studied by topical application of deuterated fatty acids in DMSO to pheromone glands. The incorporation of deuterium label into fatty acids and alcohols in the pheromone gland was monitored by gas chromatography with flame ionization detection and mass spectrometry in the selected ion monitoring mode. Dodecanol, (E)-9-dodecenol, (E,E)-8,10-dodecadienol, tetradecanol, and hexadecanol were found in gland extracts. The application of [12,12,12-2H3]dodecanoic acid resulted in labeled dodecanol, (E)-9-dodecenol, and (E,E)-8,10-dodecadienol, as well as the corresponding labeled acids. No label was incorporated into tetradecanol or hexadecanol or any acid with more than 12 carbon atoms. The application of labeled tetradecanoic or hexadecanoic acid introduced label not only into the 12-carbon alcohols, but also into tetradecanol, or tetradecanol and hexadecanol, respectively. The application of (E)-[11, 11,12,12,12,-2H5]9-dodecen-oic acid, whose facile synthesis is described, resulted in labeled (E)-9-do-decenol and (E,E)-8,10-dodecadienol. The (E,E)-8,10-dodecadienol so produced was characterized by an ion atm/z 186, equivalent to [M]+ of a dienol labeled with four deuterons. Thus, one deuterium label is lost when the labeled (E)-9-monoene is converted to the (E,E)-8,10-diene. We conclude that (E,E)-8,10-dodecadienol is synthesized by chain shortening (β-oxidation) of palmitic acid to dodecanoic acid, followed by an unusualE9 desaturation and subsequent conversion of this intermediate into the conjugated precursor, which is finally reduced to the pheromone alcohol. The evolutionary significance ofE9 desaturation being responsible for pheromone production in an Olethreutinae species is discussed.
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  • 42
    ISSN: 1573-1561
    Keywords: Anticarsia gemmatalis ; velvetbean caterpillar ; Lepidoptera ; Noctuidae ; attractant ; pheromone ; hairpencils ; (Z,Z,Z)-3,6,9-heneicosatriene ; male-produced pheromone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Observations in the laboratory and in the field indicated that maleAnticarsia gemmatalis (Hübner), the velvetbean caterpillar (VBC), are attracted to conspecific courting males. Male VBC subsequently were found to be attracted to extracts of male abdominal tips including the extrudable hairpencils. The active chemical in these extracts was identified as (Z,Z,Z)-3,6,9-heneicosatriene, which is also one of the major components of the female VBC sex pheromone. Male VBC in a wind tunnel and in the field exhibited a bimodal response distribution to a range of ratios of the (Z,Z,Z)-3,6,9-heneicosatriene and (Z,Z,Z)-3,6,9-eicosatriene, with one maximum at the pure heneicosatriene alone and the other at the 60∶40 female blend. This demonstrates that the male response to the male hairpencil component is distinct from that to the female sex pheromone.
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  • 43
    ISSN: 1573-1561
    Keywords: Lepidoptera ; Noctuidae ; sex attractants ; sex pheromones ; correspondence analysis ; chemotaxonomy ; multidimensional analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Female-emitted pheromones and sex attractants of Noctuidae were investigated using a specific computer procedure to analyze data collected from the literature. Correspondence analysis was used to survey the structure-activity relationships of sex pheromones in seven subfamilies. Structural, stereochemical, and functional features of active molecules were related to taxonomy. This multidimensional analysis revealed that the prevalent chemical frame of noctuid moth pheromones was a monounsaturated acetate withZ stereochemistry and a double bond on the fifth carbon closest to the nonfunctional branch of the molecule. Possible phylogenetic relationships within Noctuidae and between Noctuidae and other families are discussed in light of the sex pheromone biochemistry. Female sex pheromones appeared to be an additional character to be considered in the classification of noctuid moths.
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  • 44
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    Journal of chemical ecology 14 (1988), S. 1583-1596 
    ISSN: 1573-1561
    Keywords: Microplitis demolitor ; Hymenoptera ; Braconidae ; Heliothis zea ; Lepidoptera ; Noctuidae ; Biological control ; artificial diet ; preflight behavior ; wind tunnels ; oviposition ; age ; chemosensory receptors ; chilling pupae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Heliothis zea (Boddie) larvae fed cowpea seedlings produced volatile semiochemicals to whichMicroplitis demolitor Wilkinson responded in a wind tunnel. However, mostM. demolitor females reared fromH. zea larvae fed an artificial diet were not responsive at emergence to the same volatile semiochemicals. A preflight contact with frass fromH. zea fed cowpea was needed to stimulate a response of sustained flight in a wind tunnel. The most consistent flight response was 7–10 days postemergence. Response resulting from both antennal and ovipositor contact with host frass during preflight stimulation was no better than from antennal contact alone. Chilling the parasitoid pupae rendered most of the emerging females unresponsive to volatile semiochemicals.
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  • 45
    ISSN: 1573-1561
    Keywords: Tobacco budworm ; cotton bollworm ; Heliothis virescens ; Heliothis zea ; Lepidoptera ; Noctuidae ; sex pheromone ; virelure ; trapping ; pheromone interaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Evaluations conducted by placingHeliothis virescens (F.) sex pheromone (virelure) dispensers at different distances in the predominant downwind and upwind directions fromHeliothis zea (Boddie) pheromone traps indicated that reductions inH. zea male captures were greatest relative to distance when theH. zea traps were located downwind from the virelure dispensers than when the traps were located upwind. When operating traps for both species at the same site, the influence of virelure dispensers on captures inH. zea pheromone traps would be minimized by placing theH. zea traps upwind of theH. virescens traps and, if wind direction is variable, the traps should be spaced at least 75 m apart.
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  • 46
    ISSN: 1573-1561
    Keywords: Asclepias asperula ; milkweed ; Asclepiadaceae ; Danaus plexippus ; monarch butterfly ; Lepidoptera ; Danaidae ; Oncopeltus ; Hemiptera ; Lygaeidae ; cardenolide ; cardiac glycoside ; digitoxin ; chemical ecology ; chemotaxonomy ; chemical defense ; ecological chemistry ; thin-layer chromatography ; plant-insect interactions ; coevolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract This paper is the second in a series on cardenolide fingerprinting of monarch butterflies and their host-plant milkweeds in the eastern United States. Spectrophotometric determinations of the gross cardenolide content ofAsclepias asperula plants in north central Texas indicated wide variation ranging from 341 to 1616 μg/0.1 g dry weight. The mean plant cardenolide concentration (886 μg/0.1 g) is the highest for any milkweed species on which monarch cardenolide profiles have been produced. Forty-one butterflies reared individually on these plants contained a skewed distribution of cardenolide concentrations ranging from 231 to 515 μg/0. 1 g dry weight with a mean of 363μg/0.1 g. The uptake of cardenolide by the butterflies was independent of plant concentration, suggesting that saturation occurs in cardenolide sequestration by monarchs when feeding on cardenolide-rich host-plants. Female monarchs contained significantly greater mean cardenolide concentrations (339 μg/0.1 g) than did males (320 μg/0.1 g). The mean dry weight of the male butterflies (0.211 g) was significantly greater than the female mean (0.191) so that the mean total cardenolide contents of males (675 fig) and females (754 μg) were not significantly different. Butterfly size was not significantly correlated to butterfly cardenolide concentration when differences due to sex and individual host-plant concentration were removed. Thin-layer chrornatograms of 24 individual plant-butterfly pairs developed in two solvent systems resolved 22 individual spots in the plants and 15 in the butterflies.A. asperula plants appear to contain several relatively nonpolar cardenolides of the calotropagenin series which are metabolized to more polar derivatives in the butterflies. Quantitative evaluation of theR f values, spot intensities, and probabilities of occurrence in the chloroform-methanol-formamide TLC system produced a cardenolide fingerprint clearly distinct from those previously established for monarchs reared on otherAsclepias species. Our data support the use of fingerprints to make ecological predictions concerning larval host-plant utilization.A. asperula subsp.capricornu andA. viridis Walt, are the predominant early spring milkweeds throughout most of the south central United States. Cardenolide-rich monarchs reared on these two species may be instrumental in establishing and reinforcing visual avoidance of adults by naive predators throughout their spring and summer breeding cycle in eastern North America.
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  • 47
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    Journal of chemical ecology 14 (1988), S. 2033-2046 
    ISSN: 1573-1561
    Keywords: Cyclopropanation ; cyclopropanol ; enzyme inhibitor ; pheromone analog ; vinyl ketone ; Heliothis virescens ; Plutella xylostella ; α-fluoroaldehyde ; (Z)-11-hexadecenal ; (Z)-9-tetradecenal ; Lepidoptera ; Noctuidae ; Plutellidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Aldehyde components of lepidopterous pheromones are converted to carboxylic acids by aldehyde oxidizing enzymes (AOEs) that are present at high levels in antennal tissues of adult moths. The AOEs may include O2-requiring aldehyde oxidases as well as nucleotide-cofactor-requiring aldehyde dehydrogenases. Three classes of inhibitors were synthesized and examined in vitro for AOE inhibition usingHeliothis virescens antennae: (1) cyclopropanols, (2) α-fluorinated aldehydes, and (3) α,β-unsaturated carbonyls. First, cyclopropanated analogs of (Z)-11-hexadecenal (Z11–16∶A1), a common unsaturated aldehyde component of many species' pheromone blends, were synthesized as isosteric pheromone analogs and as potential inhibitors of the moth AOEs. NMR assignments are reported for thecis- andtrans-cyclopropanols. Cyclopropanols appear to act as oxidase-activated AOE inhibitors, perhaps via the unstable cyclopropanones. Second, α-fluoro and α,α-difluoro substituted analogs ofZ9–14∶A1 were synthesized and shown to be modest inhibitors of both the alcohol oxidase and AOE activities. Finally, the most potent inhibitors were α,β-unsaturated carbonyl mimics of theZ11–16∶A1. The α-methylene aldehyde was 1000-fold less effective than the vinyl ketoneZ1,11–16∶3-oxo. This inhibition appears irreversible and is postulated to involve electrophilic modification of an active site sulfur nucleophile.
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  • 48
    ISSN: 1573-1561
    Keywords: Spotted bollworm ; Earias vittella ; spiny bollworm ; Earias insulana ; Lepidoptera ; Noctuidae ; gas chromatography ; electroantennography ; pheromone traps ; hexadecanal ; (Z)-11-hexadecenal ; (E,E)-10,12-hexadecadienal ; (Z,E)-10,12-hexadecadienal ; (E,Z)-10,12-hexadecadienal ; octadecanal ; (Z)-11-octadecenal ; (E,E)-10,12-hexadecadien-1-ol
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    Notes: Abstract Ovipositor washings from virgin femaleEarias vittella (F.) (Lepidoptera: Noctuidae) moths were examined by gas chromatography (GC) linked to electroantennography (EAG). Six components were detected by the male moth. These were identified by comparison of their retention times with those of a range of synthetic standards on fused silica capillary GC columns as hexadecanal, (Z)-11-hexadecenal, (E,E)-10,12-hexadecadienal, octadecanal, (Z)-11-octadecenal, and (E,E)-10,12-hexadecadien-1-ol in 1∶2∶10∶2∶4∶1 ratio. Field testing in Pakistan showed that a 2∶10∶2 mixture of (Z)-11-hexadecenal, (E,E)-10,12-hexadecadienal, and (Z)-11-octadecenal was as attractive to maleE. vittella moths as the six-component mixture and equal in attractiveness to a virgin female moth. Omitting (Z)-11-hexadecenal or (Z)-11-octadecenal greatly reduced this attractiveness. It was found that synthetic lures must be protected from sunlight to prevent loss of attractiveness caused by isomerization of the conjugated diene aldehyde, and addition of (E,Z)-10,12-hexadecadienal, one of the products of isomerization, was shown to reduce attractiveness significantly. During this work, a 10∶1 mixture of (E,E)-10, 12-hexadecadienal and (Z)-11-hexadecenal was shown to be as attractive toE. insulana (Boisd.) male moths as a virgin female moth, and the attractiveness of this mixture was further increased by addition of (E,Z)-10,12-hexadecadienal.
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  • 49
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    Journal of chemical ecology 14 (1988), S. 1003-1021 
    ISSN: 1573-1561
    Keywords: Haloacetate ; pheromone analog ; catabolic protein ; EAG ; Plutella xylostella ; Lepidoptera ; Yponomeutidae ; inhibition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract A series of mono-, di-, and trihalogenated acetate analogs of Zl 1–16: Ac were prepared and examined for electrophysiological activity in antennae of males of the diamondback moth,Plutella xylostella. In addition, two potential affinity labels, a diazoacetate (Dza) and a trifluoromethyl ketone (Tfp), were evaluated for EAG activity. The Z11–16∶Ac showed the highest activity in EAG assays, followed by the fluorinated acetates, but other halo-acetates were essentially inactive. The polar diazoacetate and the trifluoromethyl ketone were also very weak EAG stimulants. The effects of these analogs on the hydrolysis of [3H]Z11–16∶Ac to [3H]Z11–16∶OH by antennal esterases was also examined. The three fluorinated acetates showed the greatest activity as inhibitors in competition assays, with rank order F2Ac 〉 F3Ac 〉 FAc 〉 Ac 〉 Cl2Ac 〉 ClAc 〉 Dza 〉 Br2Ac 〉 BrAc 〉 Tfp 〉 I 〉 Cl3Ac 〉 Br3Ac 〉 OH. The relative polarities of the haloacetates, as determined by TLC mobility, are in the order mono- 〉 di- 〉 trihalo, but F, Cl, Br, and I all confer similar polarities within a substitution group. Thus, the steric size appears to be the predominant parameter affecting the interactions of the haloacetate analogs with both receptor and catabolic proteins inP. xylostella males.
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  • 50
    ISSN: 1573-1561
    Keywords: Yponomeuta spp. ; Lepidoptera ; Yponomeutidae ; host plants ; Euonymus europaeus ; Celastraceae ; butenolides ; siphonodin ; isosiphonodin ; plant-insect relationship ; chemical defense ; small ermine moth ; spindle-tree
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract A new butenolide, isosiphonodin [3-hydroxymethyl-2(5H)-furanone], along with a trace of siphonodin [4-hydroxymethyl-2(5H)-furanone], was isolated from fifth-instar larvae of the small ermine mothYponomeuta cagnagellus. Leaves of its host plant spindle-tree,Euonymus europaeus, were found to contain the same two butenolides with siphonodin being present as the major compound. TLC showed that isosiphonodin was also present in larvae or pupae of six other small ermine moths which did not feed on spindle-tree. InY. cagnagellus butenolides might be plant derived, while isosiphonodin in the other investigated small ermine moths is probably synthesized by the insect. The possible role of butenolides in the chemical defense of small ermine moths is discussed.
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  • 51
    ISSN: 1573-1561
    Keywords: Sex pheromone ; inhibition ; synergism ; processionary moth ; Thaumetopoea pityocampa ; Lepidoptera ; Thaumetopoeidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The synthesis and biological activity of some analogs of (Z)-13-hexadecen-11-ynyl acetate1, the major component of the sex pheromone of the processionary mothThaumetopoea pityocampa is described. The analogs have been formally derived by structural modification of the enyne and acetate functions of the parent compound1. In field tests, trifluoroacetate ester16 and the analog,11, with fluorine substitution at the olefin site, decreased the pheromone action, whereas epoxy derivative,10, from epoxidation of the olefin moiety in1, and propionate ester15 gave synergistic activity. The formate14 had a variable effect according to the composition of the lure. Formal reduction of the enyne to give the acetylene2 was found to retain activity. Alcohols12 and13, resulting from hydrolysis of the enyne1 and acetylene2, respectively, inhibited the action of their parent compounds.
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  • 52
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    Journal of mathematical biology 26 (1988), S. 347-357 
    ISSN: 1432-1416
    Keywords: Transposable elements ; Evolution ; Branching processes ; Population genetics ; Mobile genetic elements
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract A discrete-time multitype branching process model is presented for the evolution of transposable elements in haploid populations. An individual is classified as type i if it possesses i copies of the TE, i⩾0. The general model incorporates copy-dependent selection and transposition, and recursion relations are derived for the distribution of the number of individuals of the various types. The asymptotic relative proportions of individuals of the different types is studied in the neutral case. The behavior of this equilibrium distribution is examined for various patterns of regulated transposition and deletion.
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  • 53
    ISSN: 1432-0878
    Keywords: Basement membrane ; Lipids ; Ultrastructure ; Rat (Sprague-Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Developing rat incisors were treated with malachite green-aldehyde fixative solution (MGA), which retains and stains lipids. We observed positive staining occurring as dots in the basement membrane. Most of these dots (2–3.5 nm in diameter) were grouped in the lamina densa but some were also present in the lamina lucida and the lamina fibroreticularis. These data provide evidence for the existence of lipids in the dental basement membrane and suggest that they are distributed together with the various groups of proteins so far detected.
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  • 54
    ISSN: 1432-0878
    Keywords: Adrenergic nerves ; Steroidogenic cells ; Embryonic ovary ; β 2Adrenoceptors ; Cytochemistry ; Ultrastructure ; Chicken
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The present study investigates the innervation of the embryonic chick ovary with regard to (i) development and compartmentalization of catecholaminergic nerves, and (ii) presence of adrenoceptors on steroidogenic target cells of catecholaminergic nerve terminals. Catecholaminergic nerve fibers visualized by glyoxylic acid-induced histofluorescence first appeared at embryonic day (E) 13. From E15 through E21 the density of fluorescent aminergic nerves increased markedly in parallel with the concentration of catecholamines and numbers of nerve bundles and single axons seen at the electron-microscopic level. Catecholaminergic nerves were confined to the ovarian medulla and closely associated with interstitial cells. Nerve terminals approached interstitial cells up to a distance of 20 nm and, in their majority, exhibited uptake of the false adrenergic transmitter 5-hydroxydopamine. Although adrenaline amounted to 14% of the total catecholamine content at E21, adrenaline immunoreactivity was only detected in adrenal chromaffin cells, but not in nerve fibers or cell bodies within the ovary. Interstitial cells structurally matured between E15 and E21 as documented by an increase of smooth endoplasmic reticulum and tubular mitochondria. Monoclonal antibodies mAB 120 and BRK 2 raised against avian β 1 and mammalian β 2-adrenergic receptors revealed the presence of β 2-adrenoceptor-like immunoreactivity on the surface of interstitial cells, but not on any other cell type. The results are consistent with the notion of a dense adrenergic innervation of the embryonic chick ovarian medulla and its steroidogenic interstitial cells, and suggest the chick ovary as an excellent model for elucidating the functional role of a neural input to steroidogenic cells during development.
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  • 55
    ISSN: 1432-0878
    Keywords: Smooth muscle ; Intermediate filaments ; Dual network ; Ultrastructure ; Ascidian ; Halocynthia roretzi
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary An extensive network of intermediate filaments that interconnected cytoplasmic dense bodies and connected the dense bodies to the cell surface was revealed in double-fixed, tannic acid-stained preparations of ascidian smooth muscle. The filament network ran through spaces in the continuous network of myofibrils, connecting them longitudinally, obliquely and transversely to form an intimately associated, dual network. In their transverse passage, the intermediate filaments ran across myofibrils along I-zones exclusively, interconnecting successive dense bodies. The pattern of attachment of intermediate filaments to dense bodies was predominantly “one-sided.” The filaments, which themselves were not incorporated into the contractile apparatus, remained folded or unfolded between myofibrils and between sarcomere-like structures in synchrony with the contraction-relaxation cycles. These results suggest that the intermediate filaments mechanically maintain the organization and arrangement of myofibrils via an intimate association with the myofibrils in the regions of the dense bodies, in such a way that the filaments do not impede muscle function. Based on these observations, a new model for the network of intermediate filaments in smooth muscle cells is proposed.
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  • 56
    ISSN: 1432-0878
    Keywords: Tentacles ; Ultrastructure ; Adhesion ; Leptosynapta spp (Holotheorie) ; Echinodermata
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The tentacles of the apodous holothurian Genus Leptosynapta have been studied by use of transmission and scanning electron microscopy. The gross anatomy, water vascular system, fibre systems and ectoneural nerve ring are described. A fuzzy coat of attenuated filaments covers the surface of the tentacle, broken only by secretory ducts. A cuticle underlies the fuzzy coat. Bacteria are common in the subcuticular space. Fixation without osmium gives poor preservation of the surface coats. The epidermis consists of a single layer of columnar cells consisting of Type-1, Type-2, support, goblet and uniciliated cells. Type-1 cells secrete electron-dense material and appear to be homologous to adhesive cells of the tentacles of other holothurians. The support cells contain large, granular vesicles not found in other holothurians. Goblet cells contain flocculent mucus and have an apical cilium. Goblet cells are not found in other holothurian tentacles and may function to lubricate and wrap adhering particles to aid their ingestion. The uniciliated cells are rare, poorly developed and the cilium does not extend past the cuticle. The ultrastructure of the tentacles is discussed in relation to those of other holothurians.
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  • 57
    ISSN: 1432-0878
    Keywords: Lung ; Ultrastructure ; Marsupial ; Newborn ; Surfactant ; Dasyurus hallucatus, Trichosurus vulpecula
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The lungs of newborn northern native cats, Dasyurus hallucatus and newborn brushtail possums, Trichosurus vulpecula were examined by both light and electron microscopy. The native cat has a birth weight of 18 mg after a gestation of about 21 days, whereas the brushtail possum weights 200 mg at birth and has a gestation period of 17.5 days. The lungs of the native cat are two large respiratory sacs, with a respiratory lining of squamous cells and surfactant-secreting cells. The capillaries are located within the connective tissue just below this respiratory epithelium. The visceral covering of the lung is formed by squamous cells. The lungs of the possum are composed of numerous large respiratory sacs which are separated by connective tissue septa in which the capillaries are located. The sacs, as in other species, are lined with squamous cells and surfactant secreting cells. It is proposed that the structure of the lung of the newborn marsupial is related more to the size of the newborn rather than to the length of the gestation period.
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  • 58
    ISSN: 1432-0878
    Keywords: Implantation ; Embryo ; Ultrastructure ; Vasculature ; Rat (Sprague-Dawley) ; Guinea pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Preimplantation-stage embryos were transferred to the anterior eye chamber of recipient rats and guinea-pigs. After implantation had occurred the influence of the embryo on the iris vasculature was examined ultrastructurally. In both species, the earliest effect of embryonic implantation was an increased stromal oedema. Under increasing embryonic influence the vascular endothelial cells showed an increased number of projections into the vascular lumen, while in the rat, endothelial projections were also found pushing back into the basement membrane. In the rat, the endothelium became very irregular in thickness prior to complete disintegration and loss during more advanced stages of implantation. Rat embryonic trophoblast was found invading iris vasculature, particularly in areas where the iridial endothelium was partially or completely missing. Other cells in the iris, including the stroma, appeared to be less affected. In the guinea-pig, however, trophoblast cells appeared to be capable of invading the vasculature by displacing endothelial cells that still appeared morphologically normal.
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  • 59
    ISSN: 1432-0878
    Keywords: Lateral-line sense organs ; Mechanoreceptors ; Supporting cells ; Ultrastructure ; Pleurodeles waltlii (Urodela)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructural and histochemical features of the accessory cells of the neuromast of the salamander P. waltlii have been examined. Three types of accessory cells, supporting, mantle, and basal, were found, but only the first 2 are considered in this article. Supporting cells characterized by a highly dilated endoplasmic reticulum occur among and surrounding sensory cells. Mantle cells, morphologically different from the supporting cells, surround the remainder of the neuromast. Both types of accessory cells exhibit histochemically different secretory materials. Our morphological results suggest that both accessory cells contribute to the formation of cupular material.
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  • 60
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    Cell & tissue research 254 (1988), S. 247-249 
    ISSN: 1432-0878
    Keywords: Pinealocyte ; Light exposure ; Ultrastructure ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Although it is generally known that light strongly influences N-acetyltransferase activity and melatonin production in the pineal gland, little information is available concerning morphological changes following light exposure. As exposure of rats to a short light pulse at night rapidly depresses melatonin synthesis, we decided to determine whether this experimental condition produces rapid changes in the pinealocyte organelles. A 30-min light pulse at night (six hours after lights out) provoked rapid changes in the relative volumes of some pinealocyte organelles. The volume fractions of mitochondria, Golgi apparatus and lipid droplets, and the numbers of dense-core vesicles and “synaptic” ribbons decreased, whereas the volume fraction of lysosomes increased. There were no differences in the volumes of granular endoplasmic reticulum and vacuoles containing flocculent material in those animals exposed to light compared with control animals. These results indicate that a short light pulse at night causes ultrastructural changes that can be interpreted as morphological features of diminished activity of pinealocytes.
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  • 61
    ISSN: 1432-0878
    Keywords: X-organ ; Sinus gland ; Ultrastructure ; Cyclic activity ; Siriella armata (Crustacea)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the medulla interna-medulla externa X-organ (MI-ME Xo)-sinus gland (SG) complex in the eyestalk of Siriella armata is described during the normal and the experimentally inhibited molt cycle. In the normal SG, four types of neurosecretory axon terminals, each containing distinguishable neurosecretory granules, can be described. Thus, type-2 granules are synthesized by G1 neurons forming the MI-ME Xo. The cell bodies and axonal endings of these cells in the sinus gland have been examined at the following molt stages: intermolt (stage C4), premolt (D0 and D2), and postmolt (A1, A2 and B). Changes in ultrastructure of the G1 cells have been monitored and correlated to inhibitions of the molt-and reproductive cycle produced by electrocauterization of the MI-ME Xo. The results obtained suggest that the neurosecretion from the G1 cells exerts a positive influence on molt and brood preparation. The occurrence of a distal group of G1 cells whose axons terminate at a different site from the SG suggests that the neural factors of the MI-ME Xo are diverse and control different physiological activities.
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  • 62
    ISSN: 1432-0878
    Keywords: Neuropeptide Y (NPY) ; Penis erection ; Perivascular nerve fibers immunocytochemistry ; Ultrastructure ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Neuropeptide Y 1–36 (IR-NPY) immunoreactive nerve-fiber processes have been observed in tunicae of veins and arteries and in smooth muscles of the human penis taken at autopsy or during surgery by use of light-and electron-microscopic immunohistochemical techniques. Numerous IR-NPY nerve fibers were mostly concentrated in the inner part of the adventitia close to the media of the arterial and venous vessels and among the intracavernous smooth muscle cells. IR-NPY nerve fibers were less abundant in veins than in arteries. Positive somata were not observed in the penises. At the ultrastructural level, IR-NPY were localized exclusively in large, dense granules of nerve terminals by means of the postembedding immunogold technique. In the deep dorsal vein, IR-NPY nerve fibers were also located in the media formed by an outer circular and an inner longitudinal layer. In the intracavernous and dorsal arteries, they showed the highest density in the inner part of the adventitia. In the corpora cavernosa and in the corpus spongiosum, IR-NPY nerve processes were intermingled between the smooth-muscle fibers around the sinusoid spaces. IR-NPY nerve fibers were present in the cavernous nerves close to the central arteries. The urethra did not show any IR-NPY-positive nerve fibers. This peculiar distribution of IR-NPY nerve fibers suggested that they could participate in regulating arterial and venous blood flow and intracavernous smooth-muscle tone. NPY may therefore be of importance in some of the mechanisms of penile erection especially during detumescence.
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  • 63
    ISSN: 1432-0878
    Keywords: Thymus ; Cultured thymic fragments ; Epithelial cells ; Microenvironment ; Ultrastructure ; Rat (nude)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cultured thymic fragments correspond to the thymic microenvironment depleted of lymphocytes and dendritic cells. When these fragments are implanted under the kidney capsule of congenitally athymic rats, lymphocytes and dendritic cells of host origin enter the graft and induce thymus-dependent immunity in the recipient. This paper describes the ultrastructure of the fragments and the changes that occur during the restoration of normal thymic architecture. At the end of the culture period of 6–9 days and in the early stages after implantation, the grafts consist of keratin-containing epithelial cells of unusual morphology that can be labelled with antibodies raised against the epithelium of the mid/deep cortex and the subcapsule/medulla. Normal thymic architecture develops, including nerves and blood vessels, as lymphocytes populate the environment, and by 4–6 weeks the epithelial cells are the same phenotypically and ultrastructurally as those found in normal rat thymus. However, some areas without lymphocytes still contain the atypical epithelial cells seen before implantation. Large multinucleated giant cells are also present with a few associated epithelial cells of subcapsular/medullary phenotype. In conclusion, the cultured thymic fragments contain a hitherto unknown precursor epithelial cell with an atypical ultrastructure and phenotype that is not seen in normal development.
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  • 64
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    Cell & tissue research 252 (1988), S. 581-587 
    ISSN: 1432-0878
    Keywords: Normal resting breast ; Ultrastructure ; Mitosis ; Cytokinesis ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The parenchyma of the normal “resting” human breast was examined by electron microscopy to characterize the cells undergoing mitosis and the mechanism by which the normal tissue architecture is maintained during this process. In this study of 112 mitotic cells, it was found that the mitotic cells were luminally positioned, polarised epithelial cells with no evidence of myoepithelial cell division. Ultrastructurally, the nuclear and cytoplasmic changes were consistent with previous reports of mitosis in other tissues. However, unlike all previous reports, two specific orientations of the nuclear spindle and thus the planes of cytokinesis were observed. In a few cases the spindle formed parallel to the lumen and division resulted in two luminally positioned daughter cells. However, in the majority of mitotic cells the spindle was approximately at right angles to the lumen and this orientation resulted in a luminally and a basally positioned daughter cell. It is proposed that the abnormally positioned basal daughter cell could develop into a myoepithelial cell or undergo deletion (apoptosis). Thus the two orientations of mitosis may explain the mechanism by which the epithelial and myoepithelial cell populations were maintained by a single progenitor cell without disrupting the integrity of the tissue architecture.
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  • 65
    ISSN: 1432-0878
    Keywords: Ovary ; Steroid-secreting cells ; Ultrastructure ; Chorionic gonadotropin ; Chicken
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructural characteristics of the ovarian medulla of the newly hatched white leghorn chick were studied in control animals and compared with chicks that were treated with human chorionic gonadotropin during embryonic development. The ovarian medulla was mainly occupied by epithelial cells which formed cords or islets surrounded by a basal lamina. Within this epithelial compartment, steroidogenic cells, poorly differentiated cells and a lacunary system could be recognized. When chicks were treated with human chorionic gonadotropin, steroidogenic cells became discernible; there was an increment in the amount of cytoplasm and the area of mitochondria. Poorly differentiated cells exhibited signs of stimulation, and transitional images suggested the transformation of these cells into steroidogenic cells. The epithelial cells of the lacunar system also displayed stimulated cytoplasmic organelles. Evidence was supplied suggesting that relatively undifferentiated cells persist in the ovarian medulla until hatching and can develop into steroidogenic cells under gonadotropic stimulation.
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  • 66
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    Cell & tissue research 253 (1988), S. 137-143 
    ISSN: 1432-0878
    Keywords: Endostyle ; Ultrastructure ; Immunocytochemistry ; 5-Hydroxytryptamine ; Granules ; Ciona intestinalis ; Corella parallelogramma, (Tunicata) ; Ascidia mentula (Tunicata)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The cellular and subcellular distribution of serotonin (5-hydroxytryptamine, 5-HT) in the endostyle of three species of ascidians, Ciona intestinalis, Corella parallelogramma, Ascidia mentula, was studied by light-(immunoperoxidase) and electron-microscopic (immunogold) immunocytochemistry. At the light-microscopic level 5-HT-like immunoreactivity (5-HT-LI) was exclusively found in cells located in the lateral portion of the endostyle, between zone 7, known to have iodinating capacity, and zone 8, which consists of ciliated cells. At the electron-microscopic level, the 5-HT-immunoreactive cells were found to correspond to cells containing polymorphous, dense granules, 100–300 nm in diameter. The granules were located in the supranuclear cytoplasm facing the endostyle lumen as well as in the infranuclear cytoplasm facing the extracellular space. Quantification showed that the 5-HT-LI was considerably higher (13–67 times) in cytoplasmic areas containing granules as compared to areas devoid of granules. Most, but not all, of the 5-HT-LI was associated with the dense core of the granules. In conclusion, serotonin-containing cells are located in the peripheral portion of the endostyle, between zones 7 and 8. Serotonin is stored in cytoplasmic granules that are present both in the apical and basal cytoplasm. This suggests the possibility that the cells are bipolar and secrete serotonin both in a basal direction to the extracellular space, and in an apical direction to the pharyngeal lumen.
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  • 67
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    Cell & tissue research 252 (1988), S. 349-358 
    ISSN: 1432-0878
    Keywords: Thyroglobulin ; Sulfation ; Thyroid gland ; Vertebrates ; Evolution ; Trout (Salmo gairdnerii) ; Clawed toad (Xenopus laevis) ; Chicken
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Mammalian thyroglobulin is released by thyroid follicle cells as a sulfated glycoprotein; the sulfate residues are mostly linked to tyrosine, but they are also attached to the high-mannose carbohydrate side-chains. To decide whether sulfation of thyroglobulin is confined to mammals, representatives of other vertebrate classes were analyzed for the presence of sulfated thyroglobulin: fish (trout), amphibians (clawed toad) and birds (chicken). Mini-organs were prepared from thyroid tissue and suspended in a 35SO 4 -- -containing culture medium. Light- and electron-microscope autoradiographs prepared from the mini-organs showed that thyroid follicle cells from all species examined incorporate 35SO 4 -- and synthesize a sulfated secretory product which accumulates in the follicle lumen. The Golgi complex was detected as the primary intracellular site of sulfate organification. The 35SO 4 -- -radiolabeled secretory product of all species was shown by polyacrylamide-gel-electrophoretic analyses to consist of thyroglobulin, identified by comparison with biosynthetically 125I-labeled thyroglobulin. The results indicate that the sulfation of thyroglobulin is a ubiquitous post-translational modification observed already in the thyroglobulin of lower vertebrates. Our observations suggest that sulfation of thyroglobulin was acquired in the early stages of thyroid evolution.
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  • 68
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    Cell & tissue research 251 (1988), S. 87-93 
    ISSN: 1432-0878
    Keywords: Paneth cells ; Ultrastructure ; Morphometry ; Facultative anaerobes ; Germ-free mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Germ-free mice were given live or heat-killed facultative anaerobes, and the ultrastructure of ileal Paneth cells was quantitatively examined with special reference to secretory granules showing a bipartite substructure (central core and peripheral halo). After administering live or heatkilled bacteria, there was a decrease in the area occupied by the cores of secretory granules in Paneth cells, and exocytosed core material was observed in the crypt lumen. There were no changes in the area occupied by the halo of secretory granules. None of the examined Paneth cells phagocytosed bacteria. It is concluded that certain bacteria may affect the secretion of antibacterial agents contained in the secretory granules of Paneth cells.
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  • 69
    ISSN: 1432-0878
    Keywords: Endothelium ; Swim bladder ; Capillaries ; Vesicles ; Ultrastructure ; Cryofixation ; Anguilla rostrata (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Several recent studies comparing chemically fixed and cryofixed endothelium have indicated that glutaraldehyde fixation may result in increases in the population of “vesicles” in the cytoplasm. Other reports based on ultrathin serial-section reconstruction of chemically fixed endothelium have revealed that the vesicular system is comprised of interconnected membranous compartments, which are ultimately continuous with either cell surface but do not extend across the endothelial cell. In this study, we have investigated the three-dimensional organization of the vesicular system in directly frozen, freeze-substituted capillaries of the rete mirabile from the swim bladder of the eel, specifically using the same block of embedded capillaries in which frozen capillaries had previously been found to contain less “vesicles” than chemically fixed capillaries. The results show that essentially all vesicles remain inter-connected with each other and are part of two separate sets of invaginations from the luminal and abluminal cell surface like in chemically fixed tissue. Any increase in vesicle number resulting from glutaraldehyde fixation does not affect the overall three-dimensional organization of the vesicular system in these endothelial cells.
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  • 70
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    Cell & tissue research 252 (1988), S. 123-132 
    ISSN: 1432-0878
    Keywords: Uterine epithelium ; Cell culture ; Proteins ; Ultrastructure ; Rabbit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Morphological and biochemical changes occurring in rabbit endometrial epithelial cells when placed in culture were investigated. Cells were examined by scanning- and transmission electron microscopy and freeze-fracture. Morphologically, cultured cells are shorter and broader than the columnar epithelial cells in vivo, but retain their polarity as indicated by the presence of apical microvilli and a well-developed junctional belt. To study changes in biochemical function, proteins synthesized by cells in primary culture were analyzed by two-dimensional gel electrophoresis. Proteins were labeled during a 24-h incubation with 35S-methionine and gels examined by fluorography. The pattern of proteins changed after cells had been in culture for 48 h. On day 3 new proteins were synthesized and several protein species labeled during days 1 or 2 of culture, including uteroglobin, no longer appeared. On days 3–8 of culture the protein patterns were similar. Addition of progesterone, estradiol, prolactin, or combinations of these hormones to the culture medium for 24–144 h failed to elicit consistent changes in the pattern of labeled proteins established after 3 days of culture. Minor differences in protein patterns among unrelated cultures appear to have been derived from the original cells of the culture. These results indicate that after 48 h in primary culture, cells grown in vitro resemble endometrial epithelial cells morphologically, but no longer reflect functionally the character of epithelial cells in the uterus.
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  • 71
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    Cell & tissue research 252 (1988), S. 157-163 
    ISSN: 1432-0878
    Keywords: Frog skin culture ; Desmogenesis ; Interdigitations ; Lamellipodia ; Ultrastructure ; Rana esculenta
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Small trypsinized explants from ventral skin of frogs (Rana esculenta) were maintained in culture for 4 days during which a newly formed epithelium differentiated along the cut edges of the dermis. During the first 6 h adjacent cells produced numerous interdigitating lamellipodia. After 2 days, epithelial polarity was restored by the formation of zonulae occludentes and the epithelial cells were joined by a few small newly formed desmosomes and by numerous interdigitations. Bipartite junctional complexes consisting of a zonula occludens, followed by a series of typical desmosomes, and characteristic of adult frog epidermis were formed only after 4 days. When cultured in the presence of an inhibitor of protein synthesis (cycloheximide) the trypsinized epidermis no longer formed desmosomes. Therefore pools of one or more crucial desmosomal proteins must be very low or non-existent. However, cycloheximide did not prevent the formation of cell contact specializations, consisting of a highly developed system of complex lamellar interdigitations, between adjacent cells.
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  • 72
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    Cell & tissue research 251 (1988), S. 243-248 
    ISSN: 1432-0878
    Keywords: Thoracic duct ; Smooth muscle cell ; Ultrastructure ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The three-dimensional cytoarchitecture and ultrastructure of the smooth muscle cells in the wall of the rat thoracic duct were investigated by scanning and transmission electron microscopy. The muscle layer basically consists of a single layer of circularly arranged cells. The smooth muscle cell is fusiform or ribbon-like in shape, as in veins or venules with a similar or smaller diameter. Connections by spinous processes are observed between adjacent muscle cells along their length. Spot-like membrane contacts frequently occur in areas where facing membranes are closely apposed. These are thought to be gap junctions and may be responsible for electrical coupling and mechanical attachment. Large invaginations arranged regularly in rows on the surface of the smooth muscle cells can be observed. These invaginations are closely associated with a flattened sarcoplasmic reticulum, and caveolae tend to open into the invaginations.
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    Cell & tissue research 253 (1988), S. 397-402 
    ISSN: 1432-0878
    Keywords: Paneth cells ; Ultrastructure ; Morphometry ; Atropine ; Germ-free/Ex-germ-free ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Previous studies have shown that the secretory products of Paneth cells contain antibacterial agents (lysozyme, IgA) that are affected by the bacterial milieu in the intestine. To investigate whether Paneth-cell secretion is controlled via cholinergic mechanisms, the ultrastructure of Paneth cells was studied in four animal groups: (1) germfree (GF) control mice (Jcl: ICR [GN], male, 13 weeks old), (2) GF mice injected subcutaneously with atropine sulfate (200 mg/kg body weight, dissolved in physiological saline 20 mg/ml), (3) ex-GF mice inoculated with feces from specific-pathogen-free (SPF) mice, and (4) ex-GF mice injected with atropine and inoculated with feces from SPF mice. In ex-GF mice inoculated with feces, 70–90% of the Paneth cells showed fewer secretory granules than those from GF mice (p〈0.01). Approximately 30% of the Paneth cells had a large vacuole (3–10 μm diameter) in the apical cytoplasm. Exocytosed electron-dense material from secretory granules was observed in a few crypt lumens. In ex-GF mice inoculated with feces and given atropine, about 90% of the Paneth cells contained numerous secretory granules, like those in GF control mice, but vacuolated Paneth cells and exocytotic figures were rare; thus the secretion of Paneth cells was blocked by atropine. It is therefore possible that the bacterial milieu in the intestine affects the secretory activity of Paneth cells via cholinergic mechanisms.
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    Cell & tissue research 251 (1988), S. 189-195 
    ISSN: 1432-0878
    Keywords: Lymphocytes ; Epithelium ; Mast cells ; Granular leukocytes ; Basophils ; Ultrastructure ; Chicken
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Examination, by light and electron microscopy, of the morphology and the staining properties of intraepithelial lymphocytes from the intestine of the chicken revealed a population of lymphoid cells, of which a proportion (up to 20%) is granulated. The majority of cells were immunoreactive with anti-T cell serum and can therefore be considered to be related to T-lymphocytes, but they did not proliferate when cultured with phytohaemagglutinin. The granulated cells were identical to those previously designated globule-containing leukocytes, but were distinct from mast cells in their morphology, staining reactions and the stability of the granules in different fixatives and buffers.
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    Cell & tissue research 251 (1988), S. 205-214 
    ISSN: 1432-0878
    Keywords: Kupffer cells ; Granulocytes ; Ultrastructure ; Lipopolysaccharide ; Liver ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of Kupffer cells has been studied at various times after an intravenous injection of lipopolysaccharide of Salmonella abortus equii. The most prominent effects were: an increase in the number and dimensions of phagocytic vacuoles (often containing ingested LPS and neutrophilic granulocytes); mitochondrial damage, including disintegration of the matrix and cristae; an increase in the amount of dilated, lucent rough endoplasmic reticulum; presence of fat droplets in the cytoplasm. Five days after injection of lipopolysaccharide, the Kupffer cells had resumed their normal ultrastructure. Several minutes after injection of lipopolysaccharide, platelets adhered to the Kupffer and endothelial cells. Between one and six hours, neutrophilic granulocytes accumulated in the liver sinusoids. The resulting obstruction of the hepatic microcirculation most probably affected cellular ultrastructure by ischaemia. At three days, the number of Kupffer cells was doubled, and increased further at later time intervals.
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  • 76
    ISSN: 1432-0878
    Keywords: Chromatophores ; Color change ; Ultrastructure ; Melanophores ; Macrophages ; Xanthophores ; Cichlasoma citrinellum (Teleostei: Cichlidae)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary We describe the histological basis of color metamorphosis in the polychromatic Midas cichlid, Cichlasoma citrinellum. Eight percent of the individuals in a natural population transform from gray with black markings to orange, simultaneously losing their ability to adjust coloration in response to background and social context. This trait is inherited. Light- and electron microscopy revealed that this transformation is a two-step process. First, the melanophores die, then macrophage-like cells remove the debris. As a result of this initial process, the underlying xanthophores become visible, producing the orange coloration. A similar process may occur in individuals that further transform to white, or go directly from gray to white.
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    Molecular genetics and genomics 214 (1988), S. 439-450 
    ISSN: 1617-4623
    Keywords: trpA ; trpB ; Methanococcus voltae ; Archaebacteria ; Evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A cosmid bank of Methanococcus voltae DNA was obtained in Escherichia coli after ligation of partially HindIII-digested M. voltae DNA in the HindIII site of the transferable cosmid pVK100. The bank was used to perform complementation experiments with E. coli auxotrophic mutants. Five cosmids complementing trpA shared three adjacent HindIII fragments of 2.1, 2.3 and 14 kb. Two of these cosmids also complemented trpD and carried an additional 4.2 kb HindIII fragment. The trpA- and trpD-complementing regions were more precisely localized using Tn5 mutagenesis. A 1.7 kb PstI fragment, cloned into pUC9 in both orientations, was responsible for the trpA complementation. This fragment was sequenced and an open reading frame (ORF) of 852 nucleotides (ORFtrpA) encoding a 284 amino acid polypeptide of mol. wt. 31938 was found. The amino acid sequence was compared with that of the α subunit of tryptophan synthase (trpA gene product) from nine eubacterial species and to the N-terminal part of the tryptophan synthase of Saccharomyces cerevisiae (TRP5 gene product). Similarity varied from 24% (Brevibacterium lactofermentum) to 35% (S. cerevisiae). The nucleotide sequence of the region upstream from M. voltae ORFtrpA was determined and revealed the presence of an ORF of 1227 nucleotides (ORFtrpB) encoding a 409 amino acid polypeptide of mol. wt. 44634. The polypeptide sequence was similar to the β subunit of tryptophan synthase (trpB gene product) from six eubacterial species and to the C-terminal part of the tryptophan synthase of S. cerevisiae. Similarity varied from 49% (S. cerevisiae, B. lactofermentum) to 58% (Pseudomonas aeruginosa). This high conservation supports the hypothesis of a common ancestor for the trpA and trpB genes of archaebacteria, eubacteria and eucaryotes. M. voltae ORFtrpA and ORFtrpB, which are transcribed in the same direction, are separated by a 37 bp AT-rich region. Immediately upstream from ORFtrpB, the 3′ end of an ORF homologous to E. coli and Bacillus subtilis trpF was found. As the trpD-complementing region was located upstream from the trpFBA sequenced region, the organization of trp genes in the archaebacterium might thus be trpDFBA. Such an organization resembles that of enteric eubacteria, in which the trpEDCFBA genes are grouped in a single operon. However, M. voltae ORFtrpA and ORFtrpB do not overlap, in contrast with what is found in most eubacteria.
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    Plant systematics and evolution 159 (1988), S. 229-235 
    ISSN: 1615-6110
    Keywords: AngiospermsPoaceae ; Triticum ; Evolution ; in situ hybridization ; biotin labelling ; G genome chromosomes ; repeated DNA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The somatic chromosomes ofTriticum turgicum var.durum cv. Langdon andT. dicoccoides (AABB tetraploids),T. timopheevii, andT. araraticum (AAGG tetraploids) were assayed for distribution patterns of a highly repeated 120bp DNA sequence by in situ hybridization. The repeated sequence appears to be an ancient sequence shared withSecale andAegilops. The distribution patterns of the chromosomes were compared to the patterns of the A and B genome chromosomes ofT. aestivum cv. Chinese Spring (AABBDD hexaploid).T. turgidum andT. dicoccoides were observed to have identical in situ hybridization patterns. In both species, nine chromosomes with a total of 21 sites of hybridization were observed. The pattern, with few exceptions, was identical to that of Chinese Spring.T. araraticum andT. timopheevii were observed to have different patterns. InT. araraticum, six chromosomes with 21 total hybridization sites are present while inT. timopheevii nine chromosomes with 19 total sites exist. Major differences in hybridization patterns were observed between the B and G genomes. The divergence of the tetraploid wheats in this study appears to have resulted in changes in location, not in amount, of the ancient repeated sequence.
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  • 79
    ISSN: 1615-6102
    Keywords: Cytoskeleton ; Plasma membrane ; Microtubules ; Ultrastructure ; Freeze-fracture ; Flagellates ; Proteromonas lacertae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The anterior half of the cell surface of the parasitic flagellateProteromonas lacertae is corrugated while the posterior half is covered by hair-like appendages, called somatonemes. In the anterior part, the cortical microtubules are lined by a zig-zag shaped microfibril. Here, these two structures seem to be separated from the plasma membrane. In the posterior half of the cell the somatonemes, analogous to the mastigonemes of chrysophytes, are anchored to the cortical microtubules by paired small deposits of dense material. This was clearly demonstrated by Triton X 100 treatment which solubilized the plasma membrane but left the somatonemes attached to the cortical microtubules. Freeze-fracture images revealed the alignment of clustered intramembrane particles on the P-face of the plasma membrane which correspond to the attachment sites of the somatonemes, seen as dots in thin sections. The ER-derived membrane-associated somatonemes are probably linked to the cortical microtubules by anchoring proteins which are part of the plasma membrane.
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  • 80
    ISSN: 1615-6102
    Keywords: Heat shock ; Soybean root ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Soybean seedlings (Glycine max) were incubated in narrow temperature regimes to study the effects of heat shock on cell structures. The incubation temperatures used were as follows: 1. 28 °C (2h); 2. 40 °C (2h); 3. 45 °C (2h); 4. 40 °C (2h)→45 °C (2h); 5. 47. 5 °C (10 min); 6. 40 °C (2h)→47. 5 °C (10 min). Both optical and electron micrographs were taken of the different tissues of root meristems as they responded to heat shock. Cells of roots heated to 45 °C (2h) or 47.5 °C (10 min) with lethal treatment showed drastic heat injuries:e.g., membrane damage, coagulated plasmolysis, protoplasmic contraction, and leakage of cell content. Nucleolar segregation occurred in cells treated at both lethal and supraoptimal temperatures. Seedlings preincubated at 40 °C (2 h) became thermo-tolerant to lethal temperature treatment of 45 °C (2 h) or 47.5 °C (10 min), by protecting the plasmalemma, mitochondria, plastids and nuclei from heat damage. Without preincubation, however, these structures were destroyed.
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    Protoplasma 146 (1988), S. 65-71 
    ISSN: 1615-6102
    Keywords: Apiaceae ; Eryngium campestre ; Metabolism ; Pollen grain ; P-particle ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The metabolism of P-particles (polysaccharide particles) was investigated in mature pollen grains ofEryngium campestre L. Numerous P-particles, originating from dictyosome activity, are found to be accumulated near the apertures, followed by mitochondria. A single layer of ER profiles seems to prevent the fusion of the P-particles with the intine. Instead of this, they fuse with each other forming nonmembrane-bounded polysaccharide-aggregates, which subsequently change their granulated structure to an amorphous. Mitochondria together with small vesicles are involved in the conversion-process. The so formed wall precursors pass through the ER and fuse into the intine.
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    Protoplasma 147 (1988), S. 55-63 
    ISSN: 1615-6102
    Keywords: Generative cell ; Sperm cell ; Treetomato ; Ultrastructure ; Vegetative nucleus
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    Topics: Biology
    Notes: Summary The structure of the generative cell and its association with the vegetative nucleus in the pollen tube ofCyphomandra betacea Sendt. were observed with the electron microscope. The generative cell, bounded by its own plasma membrane and the inner plasma membrane of the vegetative cell, possesses the cytoplasmic extension which lies within the embayments of a vegetative nucleus. The generative cell contains the normal complement of organelles and, especially, microtubules which cluster into several groups adjacent to the plasma membrane, oriented along the longitudinal axis of the cell. In the pollen tube reaching the lower end of the style aftersemivivo pollination, both of the sperm cells are elongated and polyribosomes and microtubules are the outstanding feature in the cytoplasm. The two sperm cells are connected by a common transverse cell wall, while cytoplasmic channels exist in both the periplasm of the two sperm cells and the transverse wall. The leading sperm cell (Svn) is closely associated with the vegetative nucleus. Thus the present study demonstrates the existence of the male germ unit in the pollen tube ofC. betacea. The possible cytoplasmic continuity between the sperm cells and between the gametes and vegetative cell is considered.
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    Protoplasma 146 (1988), S. 166-173 
    ISSN: 1615-6102
    Keywords: Entomophthorales ; Entomophthora muscae ; Ultrastructure ; Cytochemistry ; Protoplast ; in vitro growth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Entomophthora muscae (C.) Fres. can be grownin vitro as protoplasts. Light and electron microscopical studies of thein vitro developed protoplasts have demonstrated the absence of an organized wall over the protoplasmic Con A-positive membrane at all stages of growth. The cytological organization is typical of the Entomophthorales with condensed chromatin in the interphase nuclei and small eccentric metaphase spindles. Long strands of endoplasmic reticulum, microubules and vesicles surrounding the plasmalemma may be involved in maintaining the precise shape ofE. muscae protoplast. Starvation of the fungus induces the formation of hyphal bodies after deposition of Con A- and WGA-positive wall material at the plasmalemma surface.
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  • 84
    ISSN: 1615-6102
    Keywords: Aphanochaete ; Astral microtubules ; Immunofluorescence ; Phycoplast ; Spindle breakdown ; 3-D reconstruction ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The spatial and temporal organization of the microtubular cytoskeleton at the transitional stage of mitosis and cytokinesis has been studied in the chaetophoralean green algaAphanochaete magna using indirect immunofluorescence light microscopy and transmission electron microscopic analysis of serial sections including computer-aided three-dimensional reconstruction. At late mitosis, elaborate asterlike microtubule systems including bundles interconnecting both centriolar regions are present. These systems disappear a the onset of interzonal spindle disintegration. The incipient phycoplast consists of a star-shaped microtubule assemblage projecting from the intact interzonal spindle. It develops strongly at the time of spindle disintegration, later on it becomes compressed by daughter nuclei movement. Cell plate formation is associated with a two-dimensional phycoplast. Phycoplast microtubules remain for a while associated with the completed cross wall but finally they depolymerize. The general occurrence of astral microtubule systems (includingA. magna) is evaluated. The subsequent developmental stages of the phycoplast, formation, maturation and depolymerization, are discussed.
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    Protoplasma 146 (1988), S. 143-149 
    ISSN: 1615-6102
    Keywords: Hyphal tip ; Ultrastructure ; Freeze substitution ; Sclerotium rolfsii
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The hyphal tip ofSclerotium rolfsii was examined after fixation by freeze substitution. The Spitzenkörper consisted of a dense mass of apical vesicles and microvesicles surrounding a vesicle-free zone. Linear arrangements of microvesicles were occasionally observed within the Spitzenkörper. Abundant microfilaments were seen within the Spitzenkörper region, often in close association with apical vesicles and microvesicles. Microtubules passed through the Spitzenkörper and terminated at the plasmalemma at the extreme hyphal apex. Filasomes were mostly observed within the apical region and were in close proximity to the plasmalemma. Rough ER, mitochondria, microtubules, and vacuoles were abundant in the subapical region and were usually oriented parallel to the long axis of the hypha. Ribosomes were aligned on the outer surfaces of mitochondria. Golgi body equivalents were observed throughout the subapical region and appeared as inflated cisternae of varying shapes and electron opacities. Relationships to other basidiomycetous hyphal tip cells are discussed.
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    Biology and philosophy 3 (1988), S. 29-47 
    ISSN: 1572-8404
    Keywords: Louis Agassiz ; Empiricism ; Cladism ; Evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Philosophy
    Notes: Abstract The philosophy of “pattern cladism” has been variously explained by reference to the work of Louis Agassiz. The present study analyzes Agassiz's attempt to combine an empirical approach to the study of nature with an idealistic philosophy. From this emerges the problem of empiricism and of the isomorphy between the order of nature and human thinking. The analysis of the writings of Louis Agassiz serves as the basis for discussion of the “reality” of natural groups as postulated by pattern cladists.
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    Plant ecology 74 (1988), S. 107-112 
    ISSN: 1573-5052
    Keywords: Biogeography ; Desert ; Evolution ; Gradient ; Larrea
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In this paper the hypothesis is tested that the local distributions of perennial plants on a desert bajada are related to those at the regional/geographical level. Plant species reaching their highest density in the lower, mid-, or upper plant association on the bajada showed no difference in their latitudinal centers of distribution, or the latitudinal variation over the region. However, plants in the three associations did differ significally in the standardized distance of their regional distribution from the target bajada: i.e., plant species characteristic of the mid-bajada were significantly closer to their regional distribution centers than were plants in the lower or upper association. These results suggest that the local distribution of plants on desert bajadas are related to those at the regional level. Consideration of historical source-pools may provide a key to understanding both the ecological and biogeographic components of plant associations in North American desert regions.
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    Plant systematics and evolution 160 (1988), S. 123-142 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Poaceae ; Triticeae ; Evolution ; isozymes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract An electrophoretic comparison of variation at 16 presumptive isozyme gene loci was performed for 17 species from the tribeTriticeae. Included in the analysis were annuals and perennials, and self- and cross-pollinating species, representing the H, I, P, N, R, V, S, E, J, J1J2, A, B, and D genomes. Perennial species were found to contain a significantly (marginally, at the 5% level) higher proportion of polymorphic loci and level of heterozygosity, than annual species. There were no significant differences between self- and crosspollinating species. Across all species, mean heterozygosity levels ranged from 0–0.225 and the % polymorphic loci from 6.3–56.3%. Genetic distance estimates varied from 0.08–0.39 for congeneric species. Relationships were deduced between the 17 species using phenetic and cladistic analyses and compared with relationships inferred from other parameters such as morphology and nucleotide sequence data. In general, the trees derived from the various relationships were concordant; the evolutionary basis for minor discrepancies between trees is also discussed.
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    Plant systematics and evolution 160 (1988), S. 29-37 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Poaceae ; Evolution ; phylogenetic trees ; 18 S rRNA ; 26 S rRNA ; direct rRNA sequencing
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We have isolated RNA from nine different grass species and fromPsilotum, a modern representative of a primitive land plant lineage. By direct RNA sequencing with reverse transcriptase, we have determined the nucleotide sequence for five regions of the 18 S rRNA molecule and three regions of the 26 S rRNA molecule. Over 1 600 positions have been elucidated for each plant species. These sequences were aligned by computer and the variable positions were identified by inspection. The data from the variable positions were input into phylogenetic inference computer programs to generate an evolutionary relationship among the grass species. This evolutionary tree based on nucleotide sequence data was compared to a recent classification of thePoaceae based on morphological data.
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    Plant systematics and evolution 160 (1988), S. 39-59 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Poaceae ; Triticeae ; Evolution ; dispersed repeated sequences
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Four representatives of a family of dispersed repetitive sequences which were prominent and dispersed in the E genome ofThinopyrum elongatum but poorly represented in wheat, were studied in detail. The 1.4kb sequences were present both as part of tandem and more complex arrays and appeared to have resulted from repeated amplification of the sequence and their dispersion throughout the genome. Subcloning of sections of the 1.4 kb sequences resulted in probes which improved the resolution of the E genome from the genomes in wheat and enabled identification of single E genome chromosomes introduced into wheat. The generality of these types of sequences in the tribeTriticeae was confirmed by isolating analogous sequences from the R (rye,Secale cereale), V (Dasypyrum villosum), and N (Psathyrostachys juncea) genomes. — The cloned repetitive sequences from the R, V, and N genomes each showed characteristic fluctuations in amount within the grasses examined in addition to being virtually absent from wheat. It is thus possible that these sequences may provide useful taxonomic indicators for establishing relationships within theTriticeae, as well as valuable probes for tracing alien chromatin introduced into wheat.
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  • 91
    ISSN: 1617-4623
    Keywords: Erythromycin ; Kasugamycin ; Adenosine dimethylation ; Ribosomal RNA ; Evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary An inducible erythromycin resistance gene (erm) of Streptococcus pyogenes was introduced into Escherichia coli by transformation with a plasmid. The recipient E. coli cells were either kasugamycin sensitive (wildtype) or kasugamycin resistant (ksgA). The MIC values of erythromycin increased from 150 μg/ml to〉3000 μg/ml for E. coli. An extract of transformed cells, particularly a high-salt ribosomal wash, contained an enzyme that was able to methylate 23S rRNA from untransformed cells in vitro; however, 23S rRNA from transformed cells was not a substrate for methylation by such an extract. 165 rRNA and 30S ribosomal subunits of either the wild type or a kasugamycin resistant (ksgA) mutant were not methylated in vitro. Transformation of E. coli by the erm-containing plasmid led to a reduction of the MIC values for kasugamycin. This happened in wild-type as well as in ksgA cells. However, in vitro experiments with purified ksgA encoded methylase demonstrated that also in erm transformed E. coli, the ksgA encoded enzyme was active in wild-type, but not in ksgA cells. It was also shown by in vitro experiments that ribosomes from erm ksgA cells have become sensitive to kasugamycin. Our experiments show that in vivo methylation of 23S rRNA, presumably of the adenosine at position 2058, leads to enhanced resistance to erythromycin and to reduced resistance to kasugamycin. This, together with previous data, argues for a close proximity of the two sites on the ribosome that are substrates for adenosine dimenthylation.
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  • 92
    ISSN: 1573-5133
    Keywords: Comoro Islands ; Grand Comoro ; Anjouan ; History ; Living fossil ; Evolution ; Phylogenetic relationships ; Morphology ; Demography ; Reproduction ; Locomotion ; Habitat ; Predators and prey ; Gombessa ; Trade ; Endangered species ; Artisanal fishing ; Coelacanth Conservation Council
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Synopsis It all started about 400 million years ago, when representatives of a group of fish-like fleshy-finned creatures appeared in the fossil record (or was it through a childhood dream shared by all of us that we would one day study the coelacanth?). Many of the coelacanth's characters placed them close to the ancestry of terrestrial vertebrates. About 70 million years ago they disappeared from the fossil record. The discovery in 1938 of the first living coelacanth, in 1952 of the second and until now over 200 specimens parallels in excitement an encounter with a live dinosaur on a weekend walk, and in significance even more than that. For this year's 50th anniversary of the famous discovery of the first living coelacanth, we retraced the routes and visited the main actors of this zoological drama. New insights into coelacanth natural history were facilitated by novel interpretation of earlier data and our expeditions to the Comoro Islands, retracing the route of the second specimen, measuring unrecorded specimens, interviewing fishermen and describing their fishing crafts, and taking part in recent events on land and water near the only known habitat of the living coelacanth. Entry into this habitat and observations from the research submersible GEO opened up a new era in coelacanth research. Past studies of preserved specimens, which were caught as an incidental bycatch, were supplemented for the first time by studies of free-living coelacanths in their natural habitat. The first film footage taken from the submersible revealed the entirely unfishlike movements of this creature. Its mode of locomotion is a combination of flying and gliding, interspersed with head stands and belly-up drifts which appear to defy gravity. The narrow range of habitat in which the coelacanth has been encountered has led us to realize how vulnerable this ancient relict is. The members of our expeditions therefore cooperated in establishing an international organisation to coordinate efforts to conserve the coelacanth.
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    Environmental biology of fishes 22 (1988), S. 69-77 
    ISSN: 1573-5133
    Keywords: Acid ; Metals ; Ultrastructure ; Olfaction ; Electrical response ; Pollution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Synopsis The effects of acid ((H2SO4) and aluminum AIKSO4 in acidified water on rainbow trout, Salmo gairdneri, olfactory organ were examined using scanning electron microscopy and electrophysiology. Exposure to pH 4.7 resulted in an increase in the number of mucus droplets over parts of the olfactory epithelium, primarily along the ridges of the secondary folds. The addition of aluminum (5.0, 9.5, 20.0 µmol · 1−1) at pH 4.7 resulted in loss of receptor cell cilia, irregularly shaped olfactory knobs, clumped microvilli and swellings on microridge cells. Electrical responses recorded from the olfactory nerve in response to the amino acid L-serine were similar to controls in fish exposed to acidified water. When fish were exposed to acidified water and aluminum the response was depressed. These morphological and electrophysiological changes could be used to indicate metal-induced stress in fish from natural ecosystems.
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    Journal of chemical ecology 14 (1988), S. 237-252 
    ISSN: 1573-1561
    Keywords: Attractants ; extracted volatile compounds ; Synanthedon pictipes ; Lepidoptera ; Sesiidae ; chemosensory ; insect behavior ; oviposition ; mechanosensory ; host-insect interactions ; olfactory receptors ; oviposition behavior ; apple ; peach ; pear ; plant odors ; Prunus spp
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Reactions of lesser peachtree borer [Synanthedon pictipes (G&R)] to volatiles of peach wood, either natural or chemically fractionated, were observed. Mated females were stimulated by and responsive to such materials and deposited significantly more eggs on substrates, including unnatural hosts, that had been treated with aqueous mixtures of bark-canker materials. Stimulation to oviposit occurred even when the female was blinded, indicating the presence of chemical cues. Natural canker-bark extracts immediately stimulated ovipostion and for a few hours significantly increased the number of eggs laid. However, average fecundity was not increased. Antennectomy did not significantly decrease response to volatiles by gravid females, and alternate sites of such chemoreception were not located. Complex mixtures derived by solvent extraction, steam distillation, and volatiles trapping from bark, canker, and gum all had activity. Observations of insect behavior in outdoor cages and also in the laboratory indicated that visual, chemosensory, and mechanosensory receptors are involved in host finding and oviposition.
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  • 95
    ISSN: 1573-1561
    Keywords: Iridoid glycosides ; Spodoptera eridania ; Lepidoptera ; Noctuidae ; allelochemical variation ; toxicity/deterrence ; plant-insect interaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The behavioral and physiological effects of plant allelochemicals have been difficult to demonstrate; it is not often clear whether the compounds are deterrent, toxic, or both. In this study, we compared the qualitative and quantitative effects of several iridoid glycosides on a generalist lepidopteran herbivore,Spodoptera eridania (Noctuidae). Larval growth and survivorship and larval preference or avoidance were measured on artificial diets containing different iridoid glycosides at different concentrations. We also tested the toxicity/deterrence of these compounds. We found that iridoid glycosides retarded larval growth significantly at relatively low concentrations and that they were usually avoided in preference tests. The toxicity/ deterrence test did not always reflect the results of these other tests. The merits of using a variety of methods for determining deterrence and/or toxicity of plant allelochemicals are discussed.
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  • 96
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    Journal of chemical ecology 14 (1988), S. 391-399 
    ISSN: 1573-1561
    Keywords: Mexican rice borer ; Eoreuma loftini ; Lepidoptera ; Pyralidae ; sugarcane ; (Z)-13-octadecenal ; (Z)-13-ocadecenyl acetate ; (Z)-11-hexadecenyl acetate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Three chemicals isolated from ovipositor rinses of virgin femaleEoreuma loftini Dyar (Mexican rice borer) moths were identified as (Z)-13-octadecenyl acetate (I), (Z)-11-hexadecenyl acetate (II), and (Z)-13-octadecenal (III) in the approximate ratio 8∶1∶1.3, respectively. Preliminary tests indicate that in laboratory bioassays, these chemicals in the above ratio induce the same activity response as heptane extracts of rice borer ovipositors. Only one combination of two chemicals (I and III, 6.2∶1 ratio) elicited a similar response. Individual chemicals elicited no response. In field tests, the average number of male rice borer moths caught per night over a five-night period was the same in traps baited with 200–600-μg quantities of the 8∶1∶1.3 ratio of chemicals dispensed from strips of filter paper as with traps baited with virgin females. The two-component mixture (I and III, 6.2∶1 ratio) was not active in the field.
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  • 97
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    Journal of chemical ecology 14 (1988), S. 2047-2061 
    ISSN: 1573-1561
    Keywords: 11-Tetradecenyl acetate ; population genetics behavioral genetics ; Ostrinia nubilalis European corn borer ; Lepidoptera ; Pyralidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The sex pheromone communication system of the European corn borer moth varies intraspecifically. Analyses of pheromonal extracts of wild females, collected in a region where the types (each producing a different isomeric proportion ofZ- andE-11-tetradecenyl acetate) are sympatric, showed that theZ pheromone-production allele frequency was ca. 4 times greater than theE allele. The paucity ofE production and response alleles in the population indicates that moths inheriting those alleles concomitantly inherit some undefined disadvantage. The types interbreed, but the frequency of heterozygous pheromone-production types among wild females was less than predicted by Hardy-Weinberg equilibrium and was evidence of positive assortative mating. Rates of male captures in field traps baited with females of the three pheromonal types also evidenced assortative mating in the population. Progeny tests with males captured in the traps provided circumstantial evidence that pheromone response and production functions in the species are regulated by separate genetic loci and that the loci are not always complementary; i.e., a male can carry an allele coding for production of one pheromonal isomer ratio but can be genetically predisposed to respond to another.
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  • 98
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    Journal of chemical ecology 14 (1988), S. 1417-1425 
    ISSN: 1573-1561
    Keywords: Zeiraphera unfortunana ; purplestriped shootworm ; Zeiraphera destitutana ; sex pheromone ; (E)-9-dodecenyl acetate ; electroantennograms ; Lepidoptera ; Tortricidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The analyses of virgin female sex pheromone gland extracts and gland volatiles by GC, GC-EAD and GC-MS, followed by field trapping experiments, have identified (E)-9-dodecenyl acetate (E9–12∶Ac) as the primary sex pheromone component of the purplestriped shootworm,Zeiraphera unfortunana. Dosages of 1.0–10.0 μg ofE9–12∶Ac impregnated in rubber septa provide an effective trap bait and can be used for monitoring purposes.
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  • 99
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    Journal of chemical ecology 14 (1988), S. 669-682 
    ISSN: 1573-1561
    Keywords: Manduca sexta ; Lepidoptera ; Sphingidae ; feeding preference ; leaf lipid extracts ; plant surface ; hosts ; nonhosts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The role of leaf lipids in food plant selection by larvae ofManduca sexta was investigated by measuring preference responses in a two-choice preference test using glass fiber filter paper disks laced with extract (test) or water (control). The larvae respond to the petroleum ether extract of whole leaves of the host-plantLycopersicon esculentum (tomato) extract in a concentration-dependent manner. At “natural concentration” it is the most strongly stimulating extract or compound yet tested using the disk test. This response is affected by food plant experience of the larvae, suggesting stimulation by plant-specific compounds in the extract. The extract contains volatile compounds that attract the larvae. In contrast, it does not promote continued feeding on an agar-cellulose diet that incorporates the extract. Also stimulating are the extracts of leaf surfaces of two hosts,L. esculentum andSolanum pseudocapsicum, and two acceptable nonhosts,Brassicae napus andVigna sinensis, indicating the presence of nonpolar feeding stimulants at the leaf surface. However, similar leaf-surface extracts of the unacceptable plantCanna generalis were inactive, although the surface extraction process renders this plant acceptable. Leaf-surface extracts ofL. esculentum, S. pseudocapsicum, andB. napus evoke feeding responses that are qualitatively comparable to those of their corresponding leaves. However, no such parallel is found for surface extracts ofV. sinensis andC. generalis. Thus, nonpolar compounds at the leaf surface of host and some acceptable non-host-plant species strongly stimulate feeding and hence must play an important role in food selection by the tobacco hornworm.
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  • 100
    ISSN: 1573-1561
    Keywords: MBOA ; tritiated MBOA ; 6-methoxybenzoxazolinone ; Ostrinia nubilalis ; Lepidoptera ; Pyralidae ; European corn borer ; toxicokinetics ; life-cycle parameters ; body burden values ; topical application ; corn ; maize ; feeding resistance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The maize-derived secondary chemical 6-methyoxybenzoxazoii-none (MBOA) and a tritiated derivative were prepared synthetically for a detailed examination of their toxicity and toxicokinetics in the European corn borer (ECB),Ostrinia nubilalis. During feeding trials with MBOA incorporated into meridic diets (at 0, 0.5, 1.5, 2.5, and 4.0 mg/g diet), the mean time to pupation and adult emergence was significantly lengthened at concentrations of 1.5 mg MBOA/g diet and above. Increased mortality occurred at concentrations at 1.5 mg/g and above. A decrease in the sex ratio (female/ total) and fecundity was observed at concentrations of 0.5 mg/g and above. The latter observations represent new biological effects related to MBOA. In tracer studies, both uptake and excretion of MBOA administered in diets to larvae increased linearly with concentration. Body burden values indicated that the ECB larvae were capable of excreting enough compound to maintain total tissue levels at approximately 50% of the dietary concentration. Total amount of label increased with larval stage, but decreased in adults due to a large amount of label eliminated in the pupal case. In topical application studies, elimination of the label in the frass was rapid, reaching 60% by 6 hr and 82% of applied dose by 24 hr. Accumulation of label in tissues other than hemolymph was small. The results show that MBOA is toxic to ECB, but the insect has efficient methods for minimizing these effects.
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