首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
Sugi (Cryptomeria japonlca D. Don) wood powder was carbonized at varying temperatures by a onestep process up to 1000C and a two-step process using wood charcoal as the raw material up to 1600C. This study was conducted to evaluate the adsorptive properties of wood charcoal and discuss the mechanism of its adsorptive function in relation to the physical and anatomical characteristics of wood after carbonization. Anatomical characteristics of carbonized wood materials were directly observed under heating using an environmental scanning electron microscope (ESEM); the cell wall structures were analyzed by high-resolution transmission electron microscope (HRTEM). The largest weight losses were observed at the highest temperatures, in both the one-step and twostep processes but leveled off above 800C. Shrinkages in the tangential, radial, and longitudinal directions increased with carbonization temperature, peaking at 1000C. Direct observations by ESEM showed distinct shrinkage at around 400C. The first trial observations by HRTEM on the changes in the ultrastructure of cell walls of wood charcoals were done, and it was assumed to affect the formation of micropores. Adsorption was found to follow the Langmuir isotherm model. With the one-step carbonization process, the iodine adsorption capacities of the carbonized wood powders increased with increasing carbonization temperature, peaking at 800C, but decreased at higher temperatures. The wood powder carbonized at 1000C with the two-step process showed the highest capacity, but further heating up to 1400C drastically decreased the adsorption. The shrinkage of cells was related to the increases and decreases in its specific surface area. Specific surface area and total pore volume were evidently related to the adsorptive properties.Part of this paper was presented at the Second International Wood Science Seminar, Indonesia, November 6–7, 1998  相似文献   

2.
The structure of cellulose, especially the microfibril angles (MFAs), in compression wood of Norway spruce [Picea abies (L.) Karst.] was studied by wide- and small-angle X-ray scattering and polarizing microscopy. On the basis of the X-ray scattering experiments the average MF As of the cell wall layers S2 and S1 of the studied sample are 39 and 89, respectively; and the average diameter and length of the cellulose crystallites are 2.9 and 20.0nm, respectively. The average of the whole MFA distribution is shown to agree with the one obtained by polarizing microscopy of macerated fibers.  相似文献   

3.
The purpose of the study was to investigate the relation between the skin temperature of the palm and sensory cold-warmth after contact with some materials. Ten men and ten women were selected and introduced to 21 kinds of material for a contact test of 30 min without seeing the specimens in a climate-controlled room at 25±1C and 65% relative heemidity. The palm-contacted test materials and skin temperature of the palm, central fingertip, and back of the palm were measured during the experiment. A sensory evaluation test was applied to evaluate the contacted sensory cold-warmth. Results showed that the maximum temperature decrease of the fingertip (T d) was positively related to the natural logarithm of the material's specific gravity (ln u) and to the natural logarithm of the material's thermal conductivity (ln). There were also negative linear relations between the contacted sensory cold-warmth (S) with ln u and ln; and there was a negative linear relation betweenS withT d and betweenS with the value ofT d by . The thermal osmotic coefficient (b) of wood and wood-based materials ranged from 3.63 to 3.97, and the materials were qualified as good thermal insulation materials. Furthermore, there was a negative linear relation betweenS andb. Accordingly, it is possible to evaluate the contacted sensory cold-warmth relying on the basic thermal properties of material.Part of this report was presented at the 49th Annual Meeting of the Japan Wood Research Society, Tokyo, April 2–4, 1999  相似文献   

4.
Cortes  Pilar  Espelta  Josep Maria  Savé  Robert  Biel  Carme 《New Forests》2004,28(1):79-88
The use of an enriched CO2 atmosphere in tree nurseries has been envisaged as a promising technique to increase productivity and to obtain seedlings with a higher root/shoot ratio, an essential trait to respond to water stress in Mediterranean-type ecosystems. In that framework, we have analyzed the effects of three levels of atmospheric CO2 concentration (350, 500 and 700ppm) on the germination rate, growth and morphology of seedlings of two Mediterranean oaks used in reforestation programs: the evergreen Quercus ilex L. and the deciduous Quercus cerrioides Wilk. et Costa. CO2 enrichment increased the germination rate of Q. cerrioides (from 70±7 to 81±3%) while it decreased that of Q. ilex (from 71±10 to 41±12%). Seedlings of both species increased approximately 60% their total biomass in response to CO2 enrichment but at two different CO2 concentrations: 500ppm for Q. cerrioides and 700ppm for Q. ilex. This increase in seedlings biomass was entirely due to an augmentation of root biomass. Considering germination and biomass partitioning, an enriched CO2 atmosphere might not be appropriate for growing Mediterranean evergreen oaks, such as Q. ilex, since it reduces acorn germination and the only gains in root biomass occur at a high concentration (700ppm). On the other hand, a moderate CO2 enrichment (500ppm) appears as a promising nursery technique to stimulate the germination, growth and root/shoot ratio of deciduous oaks, such as Q. cerrioides.  相似文献   

5.
When (±)--oxo-guaiacylglycerol--(vanillic acid) ether (1) is degraded byFusarium solani M-13-1, the-ketone is initially reduced to giveerythro andthreo guaiacylglycerol--(vanillic acid) ethers (2), arylglycerol--aryl ethers, both of which are enantiomerically pure. The absolute configuration in each2 was determined by Mosher's method; the products were converted to,-di-(R)--methoxy--trifluoromethylphenylacetates (MTPA esters) (3) oferythro (-)- andthreo (+)-veratrylglycerol--(methyl vanillate) ethers (3), whose1H nuclear magnetic resonance (NMR) spectra were examined and compared with those of four di-(R)-MTPA ester (3) diastereomers from chemically synthesizederythro (±)-3 andthreo (±)-3. To assign the- and-MTPA-OCH3 peaks, the1H NMR scans of several compounds that have substructures of 3 and their 3,4,5-trimethoxyphenyl analogues were examined. When a racemic alcohol reacts with (R)-MTPA to give a pair of (R)-MTPA ester diastereomers, the value was defined as the absolute value of the difference in the1H chemical shifts of the peak between the diastereomers. It was found that the values of-MTPA-OCH3 were larger than those of-MTPA-OCH3 owing to a shielding effect of the veratryl ring located on the-MTPA-OCH3, and that the-MTPA-OCH3 peaks in the 3,4,5-trimethoxyphenyl compounds shifted downfield relative to those in the veratryl compounds. On the basis of the1h NMR data of (R)-MTPA esters, the absolute configuration of the four chemically prepared diastereomers (3) were determined. The catabolicerythro 3 [fromerythro (-)-3] andthreo 3 [fromthreo (+)-3] were identical to (R, S, R)-erythro 3 and (R, S, S)- threo 3, respectively. An hydrogen species in the fungal reduction would attack the-ketone fromre-face of both (R)-1 and (S)-1, givingerythro (S, R)-2 andthreo (S, S)-2, respectively.Part of this paper was presented at the 33rd Lignin Symposium, Tsukuba, November 1988  相似文献   

6.
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   

7.
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   

8.
The effects of stilbene glucosides and related compounds on termite feeding behavior were investigated using paper disc methods against the subterranean termite Reticulitermes speratus. The stilbene-rich fraction and isorhapontin (3-methoxy-3,4, 5-trihydroxystilbene-3--d-glucoside) from bark extracts of Picea glehnii showed avoidance by termites in choice tests. In the no-choice tests using compounds purified from the stilbene-rich fraction, the largest feeding deterrent effect was observed for piceid (3,4,5-trihydroxystilbene-3--d-glucoside), followed by isorhapontin, and astringin (3,3,4,5-tetrahydroxystilbene-3--d-glucoside), at the concentrations from 0.63 to 2.5µmol/disc. No change in activity was observed at retentions of more than 5.0µmol/disc. When the activities of isorhapontin and its aglycone derivative (isorhapontigenin: 3-methoxy-3,4,5-trihydroxystilbene) were compared with that of taxifolin (3,3,4,5,7-pentahydroxyflavanone) in the no-choice test, the stilbenes exhibited a larger antifeedant potential. Methylation of isorhapontigenin increased its termiticidal activity.Part of this study was presented at the 32nd Annual Meeting of the International Research Group on Wood Preservation, 2001  相似文献   

9.
The effect of a fogging system on interactions between Tetranychus urticae and Phytoseiulus persimilis was studied in two cucumber greenhouses in northern Italy. The greenhouses were divided into two compartments, one (referred to as fog area) was humidified using a fogging system and the other was not humidified (no fog area). Four cultivars were investigated: Akito and Frontera during 2000, Dinero and Jazzer during 2001. Tetranychus urticae was released on a number of plants in both compartments. The release of P. persimilis was planned in both compartments at definite T. urticae thresholds. Phytoseiid releases failed, and the colonization by other predators was scarce.Thus, the effect of the fogging system was evaluated only on T. urticae populations. During the first experimental year, spider mite populations reached low densities in the fog area of both cultivars. Higher densities were found in the no fog area, especially in late June and early July. One year later, spider mites were more abundant in the no fog area of the Dinero cultivar. On the Jazzer cultivar, where most plants were infected by powdery mildew, spider mites were less abundant and differences between the two areas were less marked. Since relative humidity values exceeding 90% (considered as effective on T. urticae) were recorded during the night when the fogging system was not active, we suggest that contact with misty water was the main factor responsible for the reduction of T. urticae populations in the fog area.  相似文献   

10.
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. .
  相似文献   

11.
Otsamo  Antti 《New Forests》2002,23(1):1-17
Ground vegetation development was studied under young plantations of Acacia mangium, A. crassicarpa, Gmelina arborea and Paraserianthes falcataria on an Imperata grassland site in South Kalimantan, Indonesia. The study was based on two separate trials: 1) a species trial with a spacing of 3×3 m, and 2) a spacing trial with progressively decreasing planting density. Both trials were established by use of intensive site preparation, NPK-fertilization, and weeding during the first year. Two years after planting and one year after the last weeding, ground vegetation in the first trial was dominated by Imperata cylindrica grass and shrubs Chromolaena odorata and Clibadium surinamense. In the open area (control) only Imperata grass appeared. Significant differences in total ground vegetation biomass (t ha–1) between the tree species were as follows: G. arborea (0.2) A. mangium (1.4) A. crassicarpa (4.2) < P. falcataria(9.6) open area (11.4). The early results from the spacing trial showed similar trends in the hardwood species' abilities in Imperata suppression. Highly significant linear relationships existed in regression analysis between the distance between planted trees and the ground vegetation biomass as follows: G. arborea (r2=0.75), A. mangium (r2=0.95), A. crassicarpa (r2=0.97), P. falcataria (r2=0.96). Tree species and their planting density should thus be critically considered in forest plantation establishment on Imperata grasslands, since ground vegetation development plays a decisive role in fire susceptibility, maintenance requirements and the promotion of native species in plantations.  相似文献   

12.
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   

13.
The entomophagous ladybird, Serangium parcesetosum Sicard (Col., Coccinellidae) appears to be a promising predator against the cotton whitefly, Bemisia tabaci (Genn.) (Hom., Aleyrodidae). Knowledge about its consumption of B. tabaci is incomplete. The present study was undertaken to determine the potential use of this predator in biological control programs. The daily and total prey consumption of S. parcesetosum through the entire development of the larval instars as well as during three different periods of longevity of adult females and males feeding on nymphs or puparia of B. tabaci as prey was examined. In addition, the daily prey consumption of the adult females where the number of B. tabaci puparia was altered was studied at two different temperatures in the laboratory. The results showed that the mean daily prey consumption of nymphs or puparia of B. tabaci by larval instars of S. parcesetosum increased gradually as development progressed at both temperatures. Significant differences were found in the mean total prey consumption among the different predatory larval instars. In total, S. parcesetosum consumed during its entire larval development significantly more nymphs than puparia; at 18°C it consumed a mean of 1,566.1 () and 1,443.9 () nymphs or 280.0 () and 250.8 () puparia, while at 30°C, it consumed a mean of 1,119.1 () and 979.9 () nymphs or 188.2 () and 171.6 () puparia. Over the three studied periods of the adult stage of S. parcesetosum, the mean daily prey consumption by the females and males fluctuated irregularly at both temperatures. At 18°C and 30°C, both females and males consumed significantly more nymphs than puparia. No significant differences were found between females and males with respect to consumption of nymphs, although significant differences were found between the sexes with respect to consumption of puparia, but at 18°C only. The mean total prey consumption over the three studied adult stages was 2,188.4 () and 1,994 () nymphs or 727.1 () and 624.8 () puparia at 18°C, while at 30°C the mean values were 3,947.7 () and 3,577.3 () nymphs or 1,600.5 () and 1,448.8 () puparia. S. parcesetosum adapted smoothly to fluctuating prey availability, where the mean daily prey consumption became higher when 50 puparia/day was offered. In contrast, the predator consumed most individuals when the number of prey supplied was 10 or 5 puparia/day. Prey consumption decreased during the second experimental week in the trial, before which 50 puparia/day had been offered. In the other trials, before which 20, 10 and 5 puparia/day had been offered, a considerable increase in prey consumption was noted.This paper is dedicated to Prof. Dr I. Akif Kansu, University of Ankara, Turkey on his 80th birthday.  相似文献   

14.
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).
  相似文献   

15.
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   

16.
In vitro propagation of Oroxylum indicum Vent. was carried out using cotyledonary node explants. Among the different types of cytokinins used for culture establishment, 6-benzyladenine exhibited the best response with higher concentrations (8.87µM or above) for inducing multiple shoots. Inclusion of indole-3-acetic acid (2.85µM) into 6-benzyladenine-supplemented medium triggered a high frequency of response as well as a proliferation of shoots. The best medium for proliferation was Murashige-Skoog (MS) medium with 6-benzyladenine (8.87µM) and indole-3-acetic acid (2.85µM). However, incorporation of gibberellic acid (1.44µM) was mandatory to enhance shoot elongation. Repeated subculturing of cotyledonary node and in vitro developed nodal segments in MS medium with 6-benzyladenine (4.44µM) at 4-week intervals resulted in continuous mass multiplication of shoots without any evidence of decline. Root induction was best (91.6%) when MS strength was reduced to one-quarter and combined with -naphthalene acetic acid (2.69µM) and indole-3-acetic acid (5.71µM), with a high survival rate (70–72%) of plantlets hardened in either soil rite or soil:sand:soil rite (1:1:2).  相似文献   

17.
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   

18.
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.
  相似文献   

19.
Zusammenfassung Die Zentren des Schadauftretens verschiedener untersuchter forstschädlicher Insekten dürften nach zahlreichen Testungen Reizzonen umfassen, welche wieder als eine Kombination von elektrischen und magnetischen Feldern und durch diese freigelegte Metalleffekte erscheinen. Untersuchungen zur möglichen Wirksamkeit dieser Komponenten auf Vitalität und Fertilität vonLymantria monacha führten zu folgenden Ergebnissen. Es erscheint möglich, daß innerhalb von Reizzonen Sterblichkeit und Fruchtbarkeit vonLymantria monacha auch von niederfrequenten elektromagnetischen oder auch konstanten magnetischen oder elektrostatischen Feldern beeinflußt werden, die direkt oder auch über die Pflanze auf die Lebenskraft der Nonne von Wirksamkeit sind. Reizzonenbereich und Normalbereich zeigten hinsichtlich der Mortalität der Versuchstiere gegensätzliche Verhältnisse. Die Anfangsmortalität innerhalb von Reizzonen war gegenüber jener der Zuchten im Normalbereich erniedrigt, die Endmortalität vielfach erhöht. Futter aus Normalbereichen setzte in den Reizzonen, Reizzonenfutter im Normalbereich die Sterblichkeit herab und erhöhte im Normalbereich die Fruchtbarkeit. Im Normalbereich mit Normalfutter gezogene Nonnen wiesen die geringsten Zahlen an abgelegten Eiern auf, was sich besonders bei an Pflanzen eingebeutelten Tieren deutlich zeigte. Die wesentlich höhere Fruchtbarkeit von Nonnen an Pflanzen im Reizzonenbereich mag zusammen mit der hier erniedrigten Anfangsmortalität eine Erklärung zum gehäuften Auftreten vonLymantria monacha innerhalb von Reizzonen geben. Freigesetzte Metalleffekte könnten innerhalb von Reizzonen die Sterblichkeit aber auch die Fruchtbarkeit erhöhen.
Summary The centres of damages by different forest insects, examined in this research, seem to be in zones of Earth radiations (Reizzonen), which again seem to be combinations of magnetic or electric fields and metal effects, set free by them. Examinations for possible influences of these components on vitality and fecundity ofLymantria monacha showed the following results: It seems possible, that inside of zones of earth radiations mortality and fecundity of this butterfly could be directed from magnetic or electric fields also of low frequency or electrostatic, which either directly or indirectly by the nutrients (plants) influence the vital power ofLymantria monacha. Zones of Earth radiations and normal zones showed different conditions in respect of the mortality. Mortality of larvae of first developmental stages inside of zones of Earth radiations was decreased, such of late stages increased contrary to larvae in normal zones. Plant-food of normal zones decreased the mortality of larvae in zones of Earth radiations and food of zones of Earth radiations decreased the mortality of those of normal zones and increased fecundity in the latter cases. Female butterflies reared in normal zones showed the lowest number of developed eggs, especially when reared encaged on living plants (spruce). The essentially higher fecundity ofLymantria monacha reared on plants inside of zones of Earth radiations together with the decreased mortality of first instar larvae there, may give an explantation for the increased population ofLymantria monacha inside of zones of Earth radiations. Metal effects set free inside of zones of Earth radiations could increase there the mortality but also the fecundity.


Herrn Prof. Dipl.-Ing. Dr. ERWIN SCHIMITSCHEK zum 75. Geburtstag.

A 1130 Wien XIII, Fasangasse 5-7, 1/8  相似文献   

20.
As part of a study on soil carbon flow in forest ecosystems, the biomass of fine roots (2.0mm in diameter) and root-associated fungi, including ectomycorrhizal fungi, were estimated in the summer season in 1998 at a Pinus densiflora (Japanese red pine) stand in western Japan. Fine roots of pine were classified into three categories: class I roots (0.5–2.0mm in diameter), long class II roots (long roots with diameter 0.5mm; IIL), and short class II roots (short roots with diameter 0.5mm; IIS). Total biomass of fine roots (I + IIL + IIS) at this stand was estimated to be 91.0gm–2, about 23% of which was class II roots (IIL + IIS). Ergosterol, which is a component of fungal membranes, was analyzed to estimate the biomass of root-associated fungi in roots. In the upper soil layers (from the surface to 13.4cm in depth), ergosterol contents in the class I, IIL and IIS roots were in the ranges 43.1–82.2, 126.1–196.3 and 271.2–321.0µgg–1 root DW, respectively. The ergosterol content was converted to fungal biomass using the median (minimum–maximum) value of ergosterol concentration reported for ectomycorrhizal fungi. Root-associated fungal biomass in this stand was estimated to be 2.0 (0.5–9.6) gm–2. The data suggest the biomass of ectomycorrhizal fungi in the P. densiflora stand is small compared with that in other forest ecosystems.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号