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1.
A new relaxation property is discussed on the basis of creep behavior of wet wood specimens pretreated with heating at various temperatures followed by quenching. The treated samples showed more marked relaxation than that of an untreated sample. The relationship between relaxation time and heating history was represented by an equation ln() = –( f – k 1)T + [ln( g) + k 2], where ln() is the logarithmic relaxation time of wet samples after quenching, T is the difference between the heating temperature and the glass transition temperature (T g), ln( g) is the logarithmic relaxation time at T g, is a constant, f is the coefficient of thermal bulk expansion, and k 1 and k 2 are constants. It was concluded from the analysis of experimental results that the change in the relaxation property caused by heating and the following quenching is due to the temporary free volume created by freezing of molecular chain motion of wood components, most probably lignin, during quenching.This work was presented at the 52nd Annual Meeting of Japan Wood Research Society, Gifu, April 2002  相似文献   

2.
Chemically synthesized (1 5)--d-glucofuranan, (1 5)--d-galactofuranan, (1 5)--d-xylofuranan, (1 5)--L-arabinofuranan, natural xylan, and curdlan were sulfated to investigate their inhibitory activities on B16-BL6 lung metastasis and anticoagulant activities. (1 5)--d-Glucofuranan sulfate, (1 5)--d-galactofuranan sulfate, xylan sulfate, and curdlan sulfate had binding abilities with B16-BL6 melanoma lysate. The inhibitory activities of sulfated polysaccharides on B16-BL6 lung metastasis selected by heparin binding assay were in the order (1 5)--d-galactofuranan sulfate > (1 5)---d-glucofuranan sulfate > xylan sulfate curdlan sulfate. Furthermore, (1 5)--d-galactofuranan sulfate, (1 5)--d-glucofuranan sulfate, and xylan sulfate had not only high inhibitory activity on B16-BL6 lung metastasis but also low anticoagulant activity. The correlation between chemical structure and biological activity is discussed.Part of this paper was presented at the 10th International Synposium on Wood and Pulping Chemistry, Yokohama, Japan, June 1999  相似文献   

3.
Summary This paper studies the influence of the used creep function, and the duration of the experimental sustained loading from which the creep function was derived, in modelling the long-term buckling strength of timber columns. The sensitivity of this buckling strength to creep and initial deflection is numerically studied using an energy approach that takes into account the initial deflection. Various creep functions — power laws as well as exponential laws — derived from bending experiments of different durations are used for the numerical simulation. The crucial need for experimental results issued from very long load period experiments is identified. Such experiments may lead to a more credible creep analysis of timber structures.Symbols i radius of giration - s stress level - EL effective MOE - E0 instantaneous MOE - I inertia moment - K,K geometrical matrices - L length of beam or column - Lf effective length - Ncr axial force, buckling load - U elastic strain energy - W external forces work - t time variable - u moisture content (m.c.) - v total deflection - vc, ve, v0 creep, instantaneous elastic and initial deflections respectively Greek Letters (t) time function - , e, 0 total, instantaneous and initial strains respectively - twist rotation - (t) creep coefficient or fractional creep or relative creep - (x) shape function - load factor - longitudinal shortening - total potential energy - creep factor - relaxation time  相似文献   

4.
Zusammenfassung Aphelenchoides ritzemabosi wurde erstmals auch anFicus elastica undRodgersia aesculiformis nachgewiesen. Schäden und typische Befallssymptome werden beschrieben und abgebildet. Die Infektion erfolgte wahrscheinlich durch Erde, in der im Jahr zuvor Chrysanthemen wuchsen, die vonAphelenchoides ritzemabosi befallen waren.
Summary Aphelenchoides ritzemabosi has been recognised for the first time atFicus elastica andRodgersia aesculiformis too. Damages and typical symptoms of affected leaves are described. The infections atFicus elastica probably were due to the earth in which the year before grew Chrysanthemum attacked byAphelenchoides ritzemabosi.Samenvatting Aphelenchoides ritzemabosi werden voor het eerst ook vastgesteld aanFicus elastica enRodgersia aesculiformis. De schade en de typische symptomen van de aangevallen bladeren wordt beschreven. De infecties aanFicus elastica zijn waarschijnlijk te wijten aan de aarde in welke het jaar daarvoor Chrysanthemum groiden, die doorAphelenchoides ritzemabosi aangevallen waren.
Résumé Aphelenchoides ritzemabosi était constaté premièrement auxFicus elastica etRodgersia aesculiformis. Des dommages et des symptomes typique aux feuilles affectées sont déscrits. Les infections auxFicus elastica sont dues probablement à la terre dans laquelle l'année passée étaient planté des Chrysanthèmes saisis parAphelenchoides ritzemabosi.
(Aphelenchoides ritzemabosi) (Ficus elastica) (Rodgersia aesculiformis). . (Aphelenchoides ritzemabosi).
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5.
Summary Review of the present studies on injurious and useful Diptera in SSRThe problems on Diptera studied in SSR as well as the names of scientists working on these problems are summarized. In SSR more than 100 scientists are working dipterologically at present. They come together biannual in order to discuss results and problems.

Dipl-Ing. Jan Dirlbek, Prag-Ruzyn, Ústav Orchany Rostlin/SSR.  相似文献   

6.
Zusammenfassung Die Altlarven 2. Generation der AmpferblattwespeAmetastegia glabrata Fall. sind im Obstbau als Schädling bekannt. Die Schäden entstehen bei dem Versuch der Larven, in Früchten Puppenkammern anzulegen.Üblicherweise verpuppen sich die Larven in den trockenen Stengeln der Nährpflanzen(Polygonaceae) oder anderem trockenem oder verholzten Pflanzenmaterial.Es wird über einen gesicherten Fall berichtet, in demAmetastegia glabrata-Larven in verarbeitetem Nutzholz (Plakattafel) schädlich geworden sind. Ein weiterer Fall konnte nicht völlig geklärt werden; jedoch waren auch hier Blaltwespen-Larven in einer Wohnung in verarbeitetes Nutzholz (Türrahmen) eingedrungen.Nach dem geringen Umfang der Schäden, die nur durch die Anlage kurzer Puppenkammern in weichen Holzteilen entstehen, istAmetastegia glabrata in die Gruppe der gelegentlichen Holzzerstörer einzureihen. Allerdings kann durch diese Art völlig gesundes Holz im Freiland angegriffen werden.Holzschutzsalze vom U-Typ genügen zur Vorbeugung nicht. Vorbeugungs- und Bekämpfungsmaßnahmen werden besprochen.
Summary Attack on wood by larvae of the dock sawfly Ametastegia glabiata Fall. (Hym., Tenthiedinidae) Normally the mature larvae of the last brood of the dock sawfly bore themselves for pupation into dry stems of plants.By the gnawing efforts in certain years of appearance in masses, however, they may attack fruit too, especially apples, and cause considerable damage by numerous gnawing spots.Besides these known injuries on fruitA. glabrata has now been stated in two cases as an occasionally dangerous animal to dry timber too.The damage caused is described by word and picture; preventive and curative measures are discussed.
Résumé Attaque du bois par des larves de la Tenthrenidé Ametastegia glabrata Fall. (Hym., Tenthredinidae) Normalment les larves adultes de l'A. glabrata se forent dans les tiges sèches des plantes pour la mé tamorphose.Cependant aussi des fruits, surtout des pommes, sont attaqués par le ronger pendant les anées quand ces insectes paraîssent en masse. Des dommages considérables sont provoqués aux points d'attaque nombreux.A côté de ces dommages connus aux fruits l'A. glabrata a été constaté en deux cas comme causeur de dommage par occasion en bois sec de construction.Les dommages sont décrits et figurés; des methodes preventives et curatives sont discutées.
? Ametastegia glabrata Fall. (Hym., Tenthredinidae) . , , , . Ametastegia glabrata Fall. ( ) . , .

Mitteilung aus dem Holzschutzlaboratorium der Farbenfabriken Bayer AG., Werb Uerdingen  相似文献   

7.
Zusammenfassung Unterschiedliche Vektoreignungen können zwischen Rassen, Morphen und Altersstadien einer Blattlausart auftreten. Es wurden verschiedene Morphen vonMacrosiphum euphorbiae (Thomas) undAcyrthosiphon pisum (Harris) hinsichtlich ihrer Übertragungsfähigkeit für das persistente Enationenvirus der Erbse geprüft. Dabei erwiesen sich ovipare Weibchen und adulte Männchen vonM. euphorbiae als ungeeignete Überträger, während die gleichen Morphen von zweiA. pisum-Populationen die Virose übertrugen. Auch die Fundatrix desA. pisum-BastardsTrifolium pratense rot XSarothamnus scoparius grün übertrug zu einem relativ hohen Prozentsatz. Ovipare Weibchen und Männchen der inaktiven RasseLotus uliginosus gelb konnten keine Infektion bewirken; die persistente Virusübertragungsfähigkeit ist im Falle vonAcyrthosiphon pisum (Harris) offenbar ein genetisch fixiertes Merkmal.
Summary Different vector abilities may exist between races, morphs and development instars of a given aphid species. Several morphs ofMacrosiphum euphorbiae (Thomas) and ofAcyrthosiphon pisum (Harris) were tested in their transmission ability for the persistent pea enation mosaic virus. Oviparous females and adult males ofM. euphorbiae proved insuitable for transmission, the corresponding morphs of twoA. pisum-populations, however, were successful in transmitting. The fundatrix of theA. pisum hybridTrifolium pratense red xSarothamnus scoparius green transmitted to a relatively high percentage. Oviparous females and males of the inactiv raceLotus uliginosus yellow failed completely in transmitting; in the present case ofA. pisum the transmission character of the persistent virus evidently is genetically fixed.
Résumé Différentes aptitudes de vecteur peuvent se trouver entre les races, les morphes et les périodes d'âge d'une espèce de pucerons. Différentes morphes deMacrosiphum euphorbiae (Thomas) et deAcyrthosiphon pisum (Harris) ont été examinées en ce qui concerne leurs aptitudes de transmettre le virus persistant du pois(pea enation mosaic). En ce cas les femelles ovipares et les mâles adultes deM. euphorbiae se montraient impropres à la transmission, pendant que les mêmes morphes de deux populations deA. pisum transmettaient la virose. C'était la fondatrice du bâtard deA. pisum Trifolium pratense rouge avecSarothamnus scoparius vert qui transmettait à une pourcentage relativement haute. Les femelles ovipares et les mâles de la race «inactive» deLotus uliginosus jaune ne pouvaient pas effectuer d'infection; en cas deAcyrthosiphon pisum (Harris), l'aptitude persistante à transmettre le virus évidemment est un caractère fixé d'une façon génétique.
, . Macrosiphum euphorbiae (Thomas) Acyrthosiphon pisum (Harris) peaenation mosaic virus). M. euphorbiae , {A. pisum} . A. pisum-Trifolium pratense Sarothamnus scoparius . «» Lotus uliginosus ; Acrythosiphon pisum (Harris) .
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8.
Zusammenfassung In Freiland- und Laborversuchen wurde die Wirkung des Pflanzenschutzmittels Sevin auf Regenwürmer untersucht. Dieser Stoff ist in Pulverform und als Suspension für diese Organismen außerordentlich gefährlich. Schon der Kontakt mit sehr geringen Mengen bewirkt schwere Lähmungserscheinungen und irreversible histopathologische Schäden.
Summary Experiments in the field as well as in the laboratory showed up the effect of the pesticide Sevin on rainworms. In the form of powder as well as a suspension this material is extremely toxic for them. Contact with smallest quantities even causes severe paralysis and irreversible histopathologic damages.
Résumé Aussi bien dans la nature que au laboratoire nous avons étudié l'activité de l'insecticide Sevin sur les vers de terre. Ce produit est en poudre ou en suspension extrémement dangereux pour ces organismes. Le seul contact avec des quantités minimes de ce produit provoquent des phénomènes de paralysie et des troubles histopathologiques irreversibles.
SEVIN . . .
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9.
Summary The Outbreak of Himera pennaria L. in 1962, in Lower Austria and Burgenland, and Causes of its break-down.The Hornbeam Measuring Worm,Himera pennaria L., hitherto described but once in forest-entomological literature as a bigscale forest pest, performed mass-attacks in 1962 in the Leitha hills (1500 acres) and Maria-Ellend wood, even clean-eating several hardwood species, especially hornbeam and also oak. The outbreak which occurred about mid-May broke perfectly down as soon as early June. The paper characterizes several bionomical and morphological data obtained during the course of the outbreak from individual development stages, also discussing the possible causes of the outbreak illustrated by climatograms. In conclusion, the biotical factors of the breakdown are treated, pointing out a virus disease (cytoplasmic polyhedrosis of mesenteron) as playing the greatest part. Along withH. pennaria L., alsoHibernia defoliaria L.,Hibernia aurantiaria Esp., andCheimatobia brumata L., as well as 4 species ofNoctuidae and 1 species ofArctiidae occurred rather frequently in the above-mentioned area, especially in the marginal zones of the Hornbeam Measuring Worm's mass-attack.
Résumé La gradation de l'Arpenteuse du Charme —Himera pennaria L. — en 1962, en Basse-Autriche et au Burgenland, et les causes de la débâcle de la calamité.L'Arpenteuse du Charme,Himera pennaria L., signalée une seule fois dans la litérature entomologique forestière comme ravageur en masse, s'est manifestée en dimensions calamiteuses en 1962, dans les montagnes du Leitha (600 ha) et au bois de Maria- Ellend, dépouillant — par endroits même de leur feullage eiitier — différentes espèces de bois feuillus, surtout des charmes mais aussi des chênes. La gradation qui s'était manifestée vers la mi-mai, subit une débacle complète dès le début de juin. Le mémoire présente quelques données bionomiques et morphologigues, obtenues au cours de la gradation, sur les différentes phases du développement, tout en discutant à l'aide de climatogrammes quelles pourraient être les causes de la gradation. En conclusion, on traite spécialement les facteurs biotiques de la débâcle, parmi lesquels une maladie à virus (polyédrose cytoplasmique du mésentère) a joué le premier rôle. Em même temps que l'Himera pennaria L., les insectes suivants ont été trouvés dans le territoire en question, le plus fréquemment dans les zones marginales de l'aire de grádation de l'Arpenteuse du Charme:Hibernia defoliaria L.,Hibernia aurantiaria Esp.,Cheimatobia brumata. L., 4 espèces de Noctuides et l espéce d'Arcttides.
Himera pennaria L. 1962 . . . . ,Himera pennaria L., -- , 1962 . (600 .) , , . , , . , , , . , ( ). H. Pennaria L. Hiberia defoliaria L., Hibernia aurantiaria Esp., Cheimatobia brumata L., 4 Noctuidade 1 Arctiidae, .

Herrn Prof. Dr. A. Acatay zum 60. Geburtstag gewidmet.

Die Untersuchungen erfolgten in Zusammenarbeit mit der Landesforstinspektion für Niederösterreich, speziell mit der Bezirksforstinspektion Wien-Umgebung und der Landesforstinspektion für das Burgenland, wofür an dieser Stelle herzlichst gedankt sei.

Für Herstellung der mikroskopischen Präparate sei Frl. H. Meldt, für die Freilandaufnahmen und mikroskopischen Aufnahmen Herrn N. Maisner bzw. Herrn O. Baschny der Forstlichen Bundesversuchsanstalt Mariabrunn, für die Aufnahmen der elektronen-mikroskopischen Präparate Herrn Hayek vom Physikalisch-chemischen Institut der Universität Innsbruck gedankt.  相似文献   

10.
Effect of cutting position on rooting and shoot growth of two poplar clones   总被引：1，自引：0，他引：1  
One-year-old shoots from stooling beds of Populus × deltoides Walker and Populus jackii Northwest were collected in late fall to determine the effect of cutting position on rooting and growth of hardwood poplar cuttings. Cuttings with a minimum diameter of 9.0 mm were obtained from basal, middle and distal locations on the poplar shoot. Rooting and shoot growth were assessed in the greenhouse and under field conditions. Walker poplar cuttings collected from basal portions of the shoot and planted in the field had 87.6% rooting and 103.8 cm growth compared to 78.8% and 103.4 cm and 67.6% and 88.8 cm for middle and distal locations respectively. For Northwest rooting and growth under field conditions was 84.4% and 94.7 cm for basal, 78.4% and 90.5 cm for mid and 64.4% and 84.3 cm for distal locations. Rooting in the greenhouse was superior to the field. Walker cuttings had fewer roots and buds per cutting than Northwest, however, growth of Walker in the field was superior.  相似文献   

11.
Summary In this paper a new method for rearingTribolium destructor is described. For oviposition the imagines are cultured in a thermostate (27° C, 70% RH) on a mixture of flour and yeast; additional feeding of pieces of fresh apple is necessary. The sifted eggs also must be stored in the thermostate. The newly hatched larvae must be isolated from the mixture of egg shells, particles of yeast, excrements of the beetles and of the remains of flour, and they get fresh food (flour-yeast-mixture). The rearing is performed in the thermostate in glass-vessels of a bigness corresponding to the developmental state of the larvae. Fully grown larvae must be isolated (for getting exactly dated material of pupae) or they are put in Petri-dishes furnished with fluted coardboard. Pupae and imagines which are not used for obtaining eggs are cultured at room temperature in darkness (flour-yeast-mixture with additional feeding of apple pieces).
Résumé Dans ce travail une nouvelle méthode de l'élevage deTribolium destructor est décrite. Pour la déposition des oeufs les adultes sont tenus dans un thermostat à température constante (27° C et 70% RH) dans une mixture de farine et de levure; en outre il faut un don supplémentaire de pomme fraî che. Les oeufs séparés en criblant sont aussi tenus dans le thermostat. Les larves qui viennent d'é clore sont à séparer de la mixture des coques d'oeuf, des particules de levure, des excréments et des restes de farine, et après elles reçoivent de la nourriture fraîche (mixture de farine et de levure). L'élevage a lieu dans des bocaux dans le thermostat. La grandeure de ces bocaux doit correspondre à l'état du développement des larves. Les larves complétement développées sont à isoler (pour obtenir du materiel des chrysalides bien datées) ou à mettre dans des bocaux »Petri« fournis de carton ondulé. Les chrysalides et les adultes, qui ne sont pas nécessaires pour la déposition des oeufs, sont á tenir à témperature de chambre dans l'obscurité (mixture de farine et de levure, de temps en temps aussi de pomme).
» «Tribolium destructor Uyttenb.). 27° C 70% PH ; . . , , ; ( ). , . ( « »-, ). , ( — , ).

Diese Untersuchung wurde im Zusammenhang mit einem größeren Forschungsvorhaben durchgeführt, das durch Unterstützung der Deutschen Forschungsgemeinschaft ermöglicht wird.  相似文献   

12.
Zusammenfassung In dem für die Besonderheiten der Kiefernrindenwanze konstruierten Olfaktometer, wurden die Chemotaxie des Schädlings auf die Terpenoide aus ätherischen Ölen der Gemeinen Kiefer untersucht. Es wurden dabei Terpenoide mit vorwiegend anlockender und abschreckender Wirkung isoliert. Einige Terpenoide (-Pinen und Limonen) verwandeln bei einer Änderung ihrer Konzentration ihre anlockenden Eigenschaften in abschreckende. Bei der Verdampfung von der Oberfläche der pflanzlichen Gewebe der Kiefer bilden die Terpenoide eine Schutzwolke — ein äußeres Schutzsystem (R-System). Bei Überwiegen der anlockenden Stoffe wird in den Dä mpfen der wirksamen Stoffe das System lockend (A-System). Es wurde ein Modell des äußeren Systems aufgebaut und ihre ungefähre mathematische Erklärung gebracht, die erlaubt, die Anlockung der pflanzlichen Gewebe der Kiefer für die Rindenwanze nach den Ergebnissen der chromatographischen Analyse der atherischen Öle zu ermitteln. Das äußere Schutzsystem der Kiefer ist eines von den Systemkomplexen, welches als Schutzfunktion die Widerstandfähigkeit der Kiefer gegen Schadinsekten erfüllt und gewährleistet.
, , .- , . /-, / . , , , /R- /, /A-/. , . .
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13.
Summary Various chemicals are used for protecting wood samples against fungi, and some of them are released in water, leading to pollution of the water. The kinetics of pentachlorophenol release in water has here been studied by considering the diffusion through the wood along the three principal axes of diffusion. The experiments and the modelling of the process is successfully coupled. The numerical model takes into account the three principal diffusivities, the partition factor, the volumes of wood and water. The effect of wood sample length along the longitudinal axis of diffusion is studied especially, as longitudinal diffusivity is much higher than the other two principal diffusivities. The effects of the relative volumes of wood and water are also of considerable interest not only for the concentration of the chemical in water but also for the rate of release.Symbols C concentration of liquid (g/cm3)_ - C c ,C eq concentration of liquid on the surface, at equilibrium with the surrounding, respectively - C i,j,k concentration of liquid in the wood at positioni, j, k - D diffusivity (cm2/s) - h coefficient of mass transfer on the surface (cm/s) - K partition factor - i, j, k integers characterizing the position in the wood - M L ,M R ,M T dimensionless numbers - M t ,M amount of chemical released after time t, after infinite time, respectively - t increment of time - L, R, T thickness of the slices taken in the wood for calculation - N L ,N R ,N T number of slices taken in the wood - x, y, z coordinates - V water volume of the surrounding water  相似文献   

14.
Synthesis of isoacteoside, a dihydroxyphenylethyl glycoside   总被引：1，自引：0，他引：1  
The total chemical synthesis of isoacteoside (1), 2-(3,4-dihydroxyphenyl)ethyl 6-O-caffeoyl-3-O-(-l-rhamnopyranosyl)--d-glucopyranoside, is described. An acteoside acetate with benzyl groups at the catechols (3: 2-(3,4-dibenzyloxyphenyl)ethyl 2,6-di-O-acetyl-4-O-[3,4-bis(O-benzyl)caffeoyl]-3-O-(-l-rhamnopyranosyl)--d-glucopyranoside) was treated with a solution of methy-lamine in methanol (MeNH2 in MeOH) to perform both deacetylation and caffeoyl migration, affording an isoacteoside derivative with benzyl groups at the catechols4b: 2-(3,4-dibenzyloxyphenyl)ethyl 6-O-[3,4-bis(O-benzyl) caffeoyl] -3-O-(-l-rhamnopyranosyl)--d-glucopyranoside —in 34% yield. Debenzylation of4b was successfully accomplished by catalytic transfer hydrogenation using 1,4-cyclohexadiene to give the target compound isoacteoside (1) in 54% yield.1H and13C nuclear magnetic resonance spectral data of the synthesized isoacteoside (1) were identical with those of the natural isoacteoside isolated fromPaulownia tomentosa (Thumb.) Steud.Part of this research was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001  相似文献   

15.
Summary It is stated that in the spreading of epizooties among small wild animals, a factor of biocoenosis played a main role, first of all some phenomena among small rodents, the field mice. In the spreading of rabies infection, a role is ascribed to an insect, theNecrophorus vespillo.The author suggests a research work to be done in that respect, and perhaps in the regions where rabies was never registered and are still free of rabies, as to establish what in a such biocoenosis is lacking that could be a factor of rabies epizooty.
Résumé A l'extension de grandes épizooties chez les animoux féroces, on considère que le grand rôle joue le facteur de biocenose, tout d'abord certains phénomènes entre les menus rongeurs, souris de champs. On attribute surtout le rôle de l'extension de l'épizootie de rage à l'insectNecrophorus vespillo. On recommende de faire des recherches dans ce but avec les autres branches de sciences naturelles et peut-être dans ces regions du monde où il n'y en avait pas et il n'y a pas aujourd'hui de rage, pour établir ce qu'il manque dans une telle biocenose et que peut être pourrait on prendre en considération comme le facteur des épisooties de rage.
, — . Necrophorus vespillo L. . , .
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16.
Summary An analysis is given which enables the shear strain in a piece of timber to be specified in terms of the difference between tangential and radial strain, herein termed the angular strain. The angular strain is then evaluated in terms of the orientation of two lines at right angles prior to deformation. The equations involved are simple and facilitate the evaluation of strain parameters which would otherwise require numerical computation.Symbols a, b, c length parameters, Fig. 2 - C half chord length - k constant of proportionality - r radial coordinate (distance from pith) - x length coordinate (board) - , angle parameters, Fig. 1 - shear strain - width of segment - angular strain - #x025B; tangential strain - r radial strain - 1, 2 components of shear strain, Fig. 1 - angle parameter, Fig. 2 - angle parameter, Fig. 3 - angle parameter, Fig. 2 The author wishes to thank Mr. J. W. Sutherland for his assistance with the presentation of this paper.  相似文献   

17.
Zusammenfassung DurchRickettsiella melolonthae (Krieg) PHILIP infizierte Maikäfer-Engerlinge wandern während des Spätherbstes und Winters im Freiland absterbend auf die Erdoberfläche. Als Begleitarten inMelolontha Larvenpopulationen kamen im Gebiet vor:Amphimallon solstitiale (L.),Anomala dubia aenea (DeG.) undMaladera brunnea (L.). MitR. melolonthae künstlich infiziert, zeigten sie im Orientierungsversuch die gleiche Aufwanderungstendenz wie kranke Maikäferengerlinge, am deutlichsten die vonM. brunnea. Auf dem Waldboden fanden sich kranke Larven dieser Art in einigen Fällen.
Summary Larvae ofMelolontha spp. infested withRickettsiella melolonthae (Krieg) PHILIP move during October– January to the top of the soil where they eventually die. Larvae ofAmphimallon solstitiale (L.),Anomala dubia aenea (DeG.) andMaladera brunnea (L.) are susceptible forR. melolonthae, too. In experiments, artificially infested individuals showed a similar tendency to move upward. This was most pronounced inM. brunnea, of which some infested larvae were found on the forest floor.
Résumé Larves du hanneton, infectées parRickettsiella melolonthae (Krieg) PHILIP, se rendent à la surface de la terre au fin de l'automme et dans l'hivers. Comme espèces accompagnant les populations larvaires deMelolontha nous avons trouvés:Amphimallon solstitiale (L.),Anomala dubia aenea (DeG.) etMaladera brunnea (L.). Ils out démonstré, après une infection artificielle avecR. melolonthae, la mème tendence dans les essais d'orientation comme les vers blancs malades deMelolontha. Le phé nomène etait le plus prononcé parmi les larves deMaladera. De cette espèce nous avons trouvés plusieurs larves malades à la surface de la terre en plein champs.
Rickettsiella melolonthae (Krieg) Philip Melolontha- . . Melolontha- :Amphimallon solstitiale (L.),Anomala dubia aenea (De G.) Maladera brunnea (L.). R. melolonthae , Melolontha-, M. brunnea. .
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18.
This study presents data on the biomass and net aerial primaryproductivity (NAPP) of two contrasting East Anglian salt marshes.One site was at Tollesbury, Essex where the marshes are of theestuarine type and are subject to marsh degradation and erosionwhile the other site was 130 km to the north at Stiffkey, Norfolkwhere the barrier-type marshes are still actively developing withno signs of erosion. The NAPP was determined by the method ofSmalley with quadrats being harvested monthly with replacement.At the lowest levels at Tollesbury there was Pioneer Marshwhich was dominated by a mixture of Salicornia spp. and Astertripolium. At higher levels at Tollesbury there was LowerMarsh which was dominated by a mixture of Atriplex portulacoides andPuccinellia maritima. Over the four years of the studyPuccinellia became the dominant species following a markeddecrease in the extent and vigour of Atriplex. At Stiffkey theMiddle Marsh was at a much higher level and the vegetation waspredominantly a short dense sward with Atriplex portulacoides,Puccinellia maritima and Limonium vulgare together with smallerquantities of Armeria maritima and Plantago maritima. The meanNAPPs over three years of the Pioneer and Lower Marsh atTollesbury (467 & 519 g m-2 yr-1respectively) were similar butin 1993 the NAPPs recorded at Tollesbury were higher than thoserecorded at Stiffkey (625 & 583 compared with 458 g m-2yr-1).Smalleys method is difficult to apply to communities wherespecies dominance is variable, especially when dominance isshared between species with markedly different growth patterns.The results for NAPP obtained from the salt marshes at Tollesburyand Stiffkey are discussed in relation to results obtained byother workers from comparable areas in England and theNetherlands. Attention is also drawn to the possibly largerbelow-ground component of production that is frequentlyoverlooked. The importance of salt marshes in relation to othercoastal communities lies in the export of a proportion of theorganic matter produced and this mainly depends on theabove-ground production.  相似文献   

19.
Four ruminally cannulated, Debouillet wethers were used in a 4×4 latin square experiment to evaluate the influence of a forb mix, a shrub mix and alfalfa (ALF) hay on ruminal fermentation characteristics and digesta kinetics of a basal grass hay/straw (GH/S; 1.04% N) diet. The grass hay was mostly blue grama (Bouteloua gracilis) mixed with barley (Hordeum vulgare) straw. Wethers were fed either the GH/S mix (7030), GH/SALF (295813), GH/Sforbs (265420), or GH/Sshrubs (265420). The forb component consisted of equal parts of scarlet globemallow (Sphaeralcea coccinea) and leatherleaf croton (Croton corymbulosus) while shrubs were composed of equal parts of fourwing saltbush (Atriplex canescens) and mountain mahogany (Cercocarpus montanus). Ruminal pH, ammonia-N, as well as total VFA concentrations and molar proportions of individual VFA did not differ among diets. Particulate passage rates tended (P>0.10) to be greater for diets containing ALF, forbs or shrubs (2.8, 2.9 and 2.8% h–1) than the GH/S diet (2.5% h–1). In situ DM and NDF disappearance of a GH/straw (5050) mix did not differ among treatments at most incubation times, except at 96 h when extent of both DM and NDF disappearance were greater (P<0.05) in sheep fed either forbs or shrubs than in those fed other diets.  相似文献   

20.
The stilbene glucoside isorhapontin (5,4-dihydroxy-3-methoxystilbene-3--D-glucoside) is the major constituent of the ethyl acetate extracts fromPicea glehnii bark. Isorhapontin inhibited the hydrolytic activity ofTrichoderma cellobiohydrolase I (CBH I) for both bacterial microcrystalline cellulose and the soluble cellooligosaccharide celloheptaitol. The inhibitory effect for celloheptaitol, however, was more drastic than that for bacterial microcrystalline cellulose. The hydrolytic activity of the CBH I core domain for celloheptaitol was also inhibited by isorhapontin to a similar extent, suggesting that the interaction between isorhapontin and the core domain of CBH I is the reason for this phenomenon. The inhibition of CBH I activity by isorhapontin showed mixed noncompetitive and uncompetitive types in a concentration of the inhibitor of less than 125M. TheK i andK i values were estimated to be 57.2 and 33.3M, respectively. Whereas isorhapontin strongly inhibited CBH I activity, its aglycone isorhapontigenin (3-methoxy-3,5,4-trihydroxystilbene) showed almost no inhibition. Consequently, both the stilbenic and the-glucosidic structures in isorhapontin are essential for the inhibitory effect on CBH I activity. Isorhapontin also inhibited the activity ofTrichoderma endoglucanase I for celloheptaitol, whereas almost no effect was observed for the activities of both endoglucanases II and III.An outline of this work was presented at the 49th Annual Meeting of the Japan Wood Research Society, Tokyo, April 1999  相似文献   

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