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1.
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   

2.
A novel method for analysis of benzylic ether type lignin–carbohydrate bonds has been developed by using model compounds. Four diastereomers of model compound 3-(4-hydroxy-3-methoxyphenyl)-2-(2-methoxyphenoxy)-3-(methyl -d-glucopyranoside-6-O-yl)-1-propanol (GGMGP), were ozonized in acetic acid/water/methanol 16:3:1 for 1h at 0°C. The product from ozonation of each diastereomer was saponified and the corresponding -etherified tetronic acid (TAMGP) was isolated using ion exchange chromatography. Minor amounts of methyl -d-glucopyranoside (MGP) and small amounts of a gluconic acid etherified with tetronic acid (TAGLCA), tetronic acid, gluconic acid, and glyceric acid were detected in the product mixture of ozonated benzylic ether type model compounds. The results suggest that a benzyl ether bond between lignin and carbohydrate is rather stable during the ozone treatment. Acid treatments with sulfuric acid or trifluoroacetic acid of the derived TAMGP led to cleavage of the glucosidic bond but only a small amount of products (tetronic acid and glucose) resulting from cleavage of the -ether bond were formed. The successful chemical treatments were used for studies of benzylic ether bonds in Japanese red pine. The results suggest the presence of benzylic ether bonds to polysaccharides in the wood.Part of this paper was presented at the 10th International Symposium of Wood and Pulping Chemistry (ISWPC), Yokohama, 1999; the 11th ISWPC, Nice, 2001; and as a rapid comunication in J Wood Sci (2000) 46:263–265  相似文献   

3.
Twelve-week-old container-grown seedlings of noble fir (Abies procera Rehd.) and Shasta red fir (A. magnifica A. Murr. var. shastensis Lemm.), both high-elevation species, were grown under controlled environments in a study of induction of terminal-bud dormancy. Eight treatment combinations of long (15 h) or short (11 h) photoperiods, warm (25°/20°C) or cool (18°/12°C) thermoperiods, and dry (–1.2 MPa) or wet (–0.6 MPa) moisture regimes were imposed upon seedlings for 12 weeks. Treatment factors significantly affecting the induction of dormancy in terminal buds of seedlings were identified over time. The results suggest that seedlings responded dynamically to dormancy cues. The warm/dry and cool/wet combinations induced dormancy in the first 2 weeks in noble fir and in the first week in Shasta red fir. Short-day/warm and long-day/cool combinations enhanced dormancy induction in weeks 3 to 4 in noble fir and in weeks 1 to 7 in Shasta red fir. Short days and cool thermoperiods independently hastened dormancy induction in noble fir in weeks 5 through 12.  相似文献   

4.
During the years 1990–1992 the seasonal development ofUnaspis euonymi (Com.) (Hom., Diaspididae) on ornamental shrubs ofEuonymus japonica L. was followed. The shrubs were at the beach park of the city of thessaloniki and that of the University campus. Branches ofE. japonica were collected and observations of the insect's development took place in the laboratory. Furthermore, sticky tape-traps were placed on the shrubs where the crawlers were trapped and counted.The first eggs were observed in late April and the first crawlers in early May. Crawlers were also observed in early July and mid September. The pick of crawlers was observed 8–10 days after the observation of the first ones. More females than males settled on the stems whereas the opposite was observed on the leaves. The male/female ratio was 14.5 on stems, 2.51 on abaxial and 2.31 on adaxial leaf surface.With 3 figures  相似文献   

5.
Rhizophora mangle L. dominated 10 overwash islands within Tampa Bay forming the northernmost mangrove forests on the west coast of Florida. The mean number of trees and basal area were 5040 trees ha-1 and 20.5m2ha-1, respectively. Basal areas ranged from 1.1 (Avicennia germinans (L.) Stern), to 2.6m2ha-1 (Laguncularia racemosa Gaertner), to 16.8 (R. mangle). Cockroach Bay mangroves are small (5.8–7.0m tall) versus coastal forests of south Florida and the Caribbean. Total litter production for a 12 month period was maximal in September for fringing (7.4gdwtm-2d-1) and interior (8.7gdwtm-2d-1) areas with the two zones not being significantly different. Average litter fall (3.1gdwtm-2d-1) was similar to more tropical Caribbean mangals. Leaves accounted for 68 of the litter and reproductive material for 6, being similar to tropical riverine and overwash marine angiosperm communities on the Mexican coast. Although mangrove forests in Tampa Bay are small in stature and experience cold damage and occasional frosts, their litter fall is similar in biomass to that of more tropical mangals. However, their reproductive output is low based on litter fall versus more tropical mangals suggesting that the northern extension is less than optimum. Macroalgal diversity was low (10 species) as compared to Caribbean mangals. Macroalgal turf (0.8gCm-2d-1) and epiphyte communities of A.germinans pneumatophores (2.7gCm-2d-1) have productivity levels that are equal to or greater than those of Caribbean mangals.  相似文献   

6.
Sphingomonas paucimobilis SYK-6 produces unique and specific enzymes, such as-etherases,O-demethylases, and ring fission dioxygenases, for lignin degradation. Cleavage of arylglycerol--aryl ether linkage is the most important process in the lignin metabolic pathway ofS. paucimobilis SYK-6. We reported the genes (ligD, ligE, ligF) for enzymes that cleaved-aryl ether linkage of dimeric compounds in previous studies. In this study we synthesized the fluorescent high-molecular-weight lignin (UBE-DHP) by dehydrogenative polymerization. We investigated the-aryl ether cleavage ability of these enzymes produced in recombinantEscherichia coli. When UBE-DHP was incubated with LigF, 4-methylumbeliferone was released as a result of-aryl ether cleavage of O-methylumbelliferyl--hydroxypropiovanillone (compound III) incorporated in UBE-DHP. Here, we report that-etherase ofS. paucimobilis SYK-6 can be expressed inE. coli and is able to cleave the-aryl ether linkage in synthetic high-molecular-weight lignin.  相似文献   

7.
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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8.
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   

9.
Zusammenfassung Es wurden in Kiefernkulturen Untersuchungen über die Tagesdynamik des Harzdruckes und der Intensität der Harzabsonderung geführt und die Ergebnisse in Beziehung zum Befallsgrad des KiefernknospentriebwicklersRhyacionia buoliana Schiff. gesetzt.Im Verlauf eines Tages variierte der Harzdruck wenig, die Intensität der Harzabsonderung dagegen stark. Die höchste Harzfluß-Intensität fällt in den Zeitraum zwischen 13 und 16 Uhr. Die Flugzeit des Wicklers, nach 18 Uhr, liegt somit außerhalb der Zeit des stärksten Harzflusses.Weder der Index der Harzfluß-Intensität noch jener des Harzdruckes zeigten eine Beziehung zur Stärke des Wicklerbefalls. Sie sind daher als Kriterien der Widerstandsfähigkeit einer Kulturkiefer gegenRh. buoliana, zumindest unter den Verhältnissen der Süd-Ukraine, nicht verwendbar.
Summary Studies on the diurnal rhythm of resin pressure and resin secretion in connection with the degree of pine-infestation byRhyacionia buoliana Schiff.In the course of one day pines in the age of 15 years showed only a small variation in resin pressure but a great one in secretion of resin. The maximal intensity of secretion was observed early in the afternoon. The moths ofRh. buoliana are flying after this time when the secretion of resin is low.There was no connection between resin pressure and secretion of resin on the one hand and the degree of pine-infestation byRh. buoliana on the other. The two factors are not suitable for indicating the degree of pine-infestation by this tortricid.

- . / 0 26 / /., , . , 13 15 . , , , , .
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10.
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   

11.
Zusammenfassung Das Ausmaß des Fraßes vonHylobius abietis L. und die dadurch verursachte Sterblichkeit wurde in Zwingern und einem Feldversuch an verschiedenen Pflanzentypen studiert. In beiden Versuchen waren die größ eren Pflanzentypen häufiger befallen als die kleineren Pflanzen. Im Zwingerversuch war auch der durchschnittliche Fraß an den größeren Pflanzen stärker. Kiefern und Fichten waren im Gesamtdurchschnitt gleich häufig und gleich stark befallen. Dagegen war die Sterblichkeit unter den Kiefern wesentlich höher als unter den Fichten. Die Empfindlichkeit verschiedener Pflanzentypen für Fraßschäden wurde als Index aus der prozentualen Sterblichkeit und dem mittleren Ausmaß des Fraßes pro befallener Pflanze bestimmt. Danach waren die kleineren Pflanzen im allgemeinen wesentlich empfindlicher als großere Pflanzen und Kiefern empfindlicher als Fichten. Zucht der Pflanzen während einer Vegetationsperiode im Treibhaus erhöhte nicht ihre Anfälligkeit für Russelkäferschäden.
Summary In cages and a field experiment the degree of feeding by the pine weevilHylobius abietis L. and the plant mortality caused by the attack were studied in different types of conifer plants. The plants of the larger types were more often attacked than the smaller plants in both experiments. In the cages the mean degree of feeding was also higher for the larger plants. In the total mean Scots pine and Norway spruce were attacked with the same frequency and in the same degree. The plant mortality, however, was considerably larger in pine than in spruce. The sensitivity of different plant types to feeding damage was determined as an index from the percentage plant mortality and the mean degree of feeding per attacked plant. The index showed a generally higher sensitivity in smaller plant types than of larger ones. Pine was more sensitive than spruce. Breeding of plants in a plastic greenhouse during one vegetation period did not raise their disposition towardsHylobius-attack.

Résumé Le dégré de nutrition de l'Hylobius abietis L. et la mortalité due à l'attaque ont été étudiés en cages et dans une expérience en plein champ chez différentes espèces de conifères. Dans les deux expériences, les plus grandes plantes ont été attaquées plus souvent que les moins grandes. Dans les cages la quantité moyenne de nutrition a aussi été plus considérable pour les grandes plantes. La fréquence et la force des attaques ont été les mmes chez les pins et les épicéas. Par contre la mortalité a é té notablement plus élevée chez les pins. La sensibilité des différentes plantes aux dégâts de nutrition a été exprimée comme un index et determinée à partir du taux de mortalité des plantes et du degré moyen de nutrition par plante attaquée. L'index a montré en général une plus grande sensibilité chez les moins grandes plantes que chez les plus grandes. La sensibilité du pin a été plus grande que celle de l'épicéa. La culture des plantes en serre pendant une période de végétation n'augmente pas leur disposition aux attaques des hylobies du pin.

, ,Hylobius abietis L., , . , . , . , . , . () . ó , , . .
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12.
Summary Larvae ofErnobius spp. and adults ofBrachyderes incanus were serious pests of shoots ofPinus silvestris andP. contorta at several localities of Rhine valley and near Meppen/Ems.In the same areas aphids(Lachninae) and their predators were very abundant.Protolachnus agilis Kltb. became very harmful on young pines in experiment field cages where predators had been excluded.Pineus sp. was frequent in the field cages and in young pine plantations near Meppen.
Résumé En divers endroits de la vallée du Rhin et près de Meppen/Emsland, des larves d'Ernobius spp. et des adultes deBrachydeles incanus furent observés comme étant de sérieux pour les jeunes pousses dePinus silvestris et deP. contorta.Dans les mêmes régions des pucerons(Lachninae) et leurs prédateurs étaient très abondants.Protolachnus agilis Kltb. divint très nuisible aux jeunes pins placés dans des cages expérimentales où les prédateurs avaient été enfermés.Pineus sp. é tait aussi abondant dans cages expérimentales et dans les plantations de jeunes pins près de Meppen.

Meppen/Emsland Eronobius spp. Brachyderes incanus, Pinus silvestris P. contorta. (Lachninae) Protolachnus agilis Kltb. , - .Pineus sp. - Meppen.
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13.
A suitable screening method for heterozygous DNA markers in shiitake,Lentinula edodes (Berk.) Pegler, is reported. Monokaryons were derived from a dikaryon by de-dikaryotization via protoplast formation. Compatibility of the monokaryons was determined by pairwise culture on agar plates. We selected the primers to amplify polymorphic fragments among the original strain (Hokken600H600) and two monokaryons (H600PP-39 and H600PP-67) showing compatibility. A total of 135 fragments were selected as specific random amplified polymorphic DNAs (RAPDs) resulting from 56 primers of the 147 primers tested. Furthermore, we tested whether the polymorphic fragments segregated into 22 among four strains isolated from a basidium. Most of the polymorphic fragments (about 97.8%) showed 22 segregation among the four strains. We concluded that the polymorphic fragments were heterozygous if they were detected in either of the monokaryons (H600PP-39 and H600PP-67) and segregated to 22 among four meiotic strains (H600B-1,-2, -3, and -4). A total of 132 heterozygous DNA markers were therefore selected from a dikaryon of shiitake (Hokken600H600).Part of this report was presented at the 8th Annual Meeting of Mushroom Science and Biotechnology and the 47th Annual Meeting of the Japan Wood Research Society, Kochi, 1997  相似文献   

14.
Summary A -d-(13)-linked glucan has been isolated from compression wood of tamarack [Larix laricina (Du Roi) K. Koch]. The polysaccharide, which had []D + 17.6°, consumed 0.17 mole of periodate per glucose residue and gave a methyl derivative which consisted of 115 2,4,6-tri- and 2,3,4,6-tetra-O-methyl-d-glucose residues in a ratio of 17.8:1. Partial acid hydrolysis yielded a series of -d-(13)-linked oligosaccharides, while enzymic hydrolysis with a -1,3-glucanase afforded glucose, laminaribiose, and laminaritriose. The glucan occurred in amounts varying from 2 to 4% in compression wood of this and other conifer species and was present in the wall of both tracheids and ray cells. It is proposed that this structural polysaccharide be designated as laricinan to distinguish it from callose and the various -1,3-glucans in lower plants.  相似文献   

15.
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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16.
In this study, the susceptibility of larvae and adults of Tribolium castaneum (Herbst) to gamma radiation was investigated in the laboratory in Turkey. Gamma radiation was applied at 6 dose levels between 20 and 200Gy to 13–15day-old adults and at 5 dose levels between 20 and 180Gy to 18–20day-old larvae of T. castaneum. All experiments were performed in growth chambers maintained at 27±1°C and 70±5% r.h. The larvae proved to be the more susceptible stage, survival to the adult stage being prevented by exposure of the eggs to 100Gy; the adult stage was less susceptible. LD50 and LD99 values were determined as 19,75 and 42,97Gy for larvae and 33,21 and 64,50Gy for adult stage, respectively. It was concluded that 100Gy is the effective dose for both larval and adult stages.  相似文献   

17.
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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18.
The extractives of shirakamba (Betula platyphylla Sukatchev var.japonica Hara) leaves were investigated. Two lignan glycosides were isolated, and their structures were elucidated to be 1-(4-hydroxy-3-methoxyphenyl)-2-[1-(3--l-rhamnopyranosyloxypropyl)-3-hydroxyphenoxy]-1,3-propanediol (I) and a new 2,3-dihydro-2-arylbenzofuran configuration neolignan,cis-2,3-dihydro-2-(4--l-rhamnopyranosyloxy-3-methoxyphenyl)-3-hydroxymethyl-7-hydroxy-5-benzofuranpropanol (II). These neolignan rhamnosides were newly found in shirakamba.  相似文献   

19.
Summary During the application of several acaricides to manifest their effectivness againstPanonychus ulmi Koch living on the apple trees in Lebanon, it could be clearly noticed that a kind of resistance to the phosphoric acid organic preparations occurs, where these mentioned chemicals are regularly used against the mites. The control succes by means of some acaricides and ovicides combinations is here discussed. AsTetranychus urticae Koch in some apple plantations infests the different weeds growing together with the trees there and it wanders in summer to overrun the apple trees; the question of the mite control by means of respective sprays or by means of weed eradication is also discussed.
Résumé L'étude de l'efficacité d'une série d'acaricides dePanonychus ulmi Koch sur pomme en Liban a démontré une certaine résistance de groupes des parathions, lá où ceux — ci sont appliqués régulièrement depuis des années. Les résultats de combat de quelques acaricides et combinaisons par des ovicides sont discutés. PuisqueTetranychus urticae Koch occupe les herbes, les plus différentes, et depuis — là en été change sur les pommiers la question d'un combat de cet acarien nuisible par des application ultérieures ou par l'extermination d'herbes est discuté e.

, Pannonychus ulmi Phosphorsäureester. Akarizide Ovizide. Tetranychus urticae , .
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20.
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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