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1.
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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2.
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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3.
Summary In the introduction a historical survey is given about the development of the registration service of pests. It can be seen that originally informations of the appearance of pests was mostly given by agricultural and horticultural experts in special journals of agriculture and horticulture.It is well known that a registration service was set up when a Plant Protection Organisation was foundet. Its efficiency has never ceased since its beginnings. These efforts are foundet intensionally to register the existence of pests as completely as possible.The registration service starting first of all from the damage caused by the pests maybe well understood.Our research work being a continuous contribution to the systematic registration of pests generally shows in a number of examples the heterogeneous character of the problem which must be studied concerning the individual pests and difficulties which arise. This is shown with regard to someElaterides and also because of experiments withLaspeyresia funebrana Tr. during several years.In accordance withKirchner and F. P.Müller, Rostock, we propose to register systematically a number of pests on index cards according to uniform principles in the whole of Europe, to register the vertical and horizontal appearance of pests with the same measure, in the same periods of classification and in the same way (seeAuersch 1 to 3).We are encouraged to do so by a number of appreciated views of specialists from Germany and foreign countries however it is, not enaugh to see the great importance of the card index (card-register) and to acknowledge its practicability, but it can only prove its efficiency if it is generally introduced.The systematic registration of pests will enable us to gather in the course of time empirical data, the reliability and evidence of which will steadily increase.
Résumé On commence par livrer un aperçu historique sur le développement du système de rendre compte relativement aux plantes nuisibles. En lisant ces comptes rendus on peut reconnaître que les rapports donnés au début sur l'apparition des plantes nuisibles furent livrés en substance par la pratique agricole et jardinière par des revues spéciales de l' agriculture et de l'horticulture.Il est connu qu'avec l'établissement du service pour la protection des plantes on a établi un service de comptes rendus, au perfectionnement duquel on a travaillé dès son existance.Ces efforts furent influencés et activés par l'idée de saisir l'apparition des plantes nuisibles aussi complétement que possible. Le service des comptes rendus s'est orienté d'abord en première ligne aux dommages produits, ce qui est aisé à comprendre.Puisque notre traité doit être en général une contribution ultérieure à la connaissance systématique de l' apparition des plantes nuisibles, on explique au moyen de plusieurs exemples, comment sont différentes les questions se rapportant aux plantes nuisibles individuelles, questions qu'il faut ainsi prendre en considération et quelles difficultés en résultent. Cela est démontré pour quelques élatérides de même que sur la base d'examinations exécutées pendant plusieurs années avecLaspeyresia funebrana Tr.En concordance avecKirchner et F. P.Müller, Rostock, nous proposons de saisir systématiquement en classeurs à fiches une série de plantes nuisibles selon des points de vue uniformes, cela veut dire d'enregistrer dans les fiches proposées l'apparition verticale et horizontale des plantes nuisibles avec des mesures égales, dans les mêmes périodes d'examen et appréciation des qualités productives du sol et dans la même manière (voireAuersch 1 à 3).Nous sommes encouragés à faire ces propositions avant tout par des assentiments à notre disposition, qui nous ont été envoyés de la part des cercles compétents de notre pays et de l'é tranger. Il ne suffit pas cependant de reconnaître le fichier dans sa signification variée et d'apprécier son utilisation; le fichier peut faire ses preuves plutôt seulement, s'il est introduit en général. Au cours du temps il sera possible d'obtenir des valeurs expérimentelles par le fichement systématique des plantes nuisibles, dont la sûreté et faculté de déposition augmente constammant avec la durée de leur existence.

õ . : . . . . õ . . , . Elateriden uLaspeyresia funebrana Tr. . . . , , , . . ( 1 3.) . . , . . .
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4.
Zusammenfassung Reflexionen zu dem offenen Problem, inwieweit Imagines necrophager Dipteren, — deren Maden im Zentralnervensystem von an Tollwut(Lyssa) verendeten Wirbeltieren zur Entwicklung gelangten —, logischerweise als eventuelle direkte (durch Kontakt-Infektion) oder indirekte (z. B. als Beute von Fledermäusen) Vektoren dieser Virose verdächtigt werden könnten —?
Summary Reflections belonging the open problem, how far imagines of necrophagous dipters, — if theirs maggots developed in the nervecentre-system of such vertebrats, which succumbed by lyssa —, logically are suspected, perhaps to be vectors of this virose, either directly (by contact-infection) or indirectly (for example to be prey to the bats) —?

Résumé Rèflexions à ce propos de discuter le problème ouvert, jusqu'à quel point les individues volants des diptères necrophages, — dont mites se developpaient au milieu du système nerveux central de vertébrés, succombés par lyssa —, sont soupçonnés logiquement d'être peut-être des vectors de cette virose, ou directement (par mettre en contact infectieux) ou indirectement (par exemple d'être butin des chirotères) —?

, , (Imagines), —, , (Lyssa) — ( ) ( ) .
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5.
Zusammenfassung 1. Die Intensität der Harzausscheidung ist kein sicheres Kriterium bei der vergleichenden Diagnose der Widerstandsfähigkeit verschiedener Kiefern-Arten gegen Schadinsekten. In dem Widerstandsmechanismus der Kiefer spielt nicht die Quantität des Harzes, sondern die Qualität eine Rolle und unbedingt seine biologische Aktivität.2. Kiefeinharz ist ein natürliches Schutzmittel des Baumes gegen. Insektenschäden. Verschiedene Kiefern-Arten enthalten Harz von qualitativ verschiedener biologischer Aktivität für Insekten. Das bezieht sich auch auf das Harz ein- und derselben Kiefernart bei unterschiedlichem physiologischen Zustand. Das Harz der geschwächten Kiefernbäume verliert seine Schutzeigenschaften und sein Geruch wirkt auf Insekten als ein Zeichen der Eignung des Baumes für ihre Ernährung und Entwicklung.3. Die biologische Aktivität des Harzes ist durch die in ihm vorhandenen ätherischen Öle, die auis Terpenoiden bestehen, bestimmt. Die Terpenoide besitzen für die Insekten verschiedene biologische Aktivitä t, welche von ihrer Menge, ihren Eigenschaften, den Beziehungen der Komponenten untereinander und optischen Isomeren abhängen, die insgesamt ihre Qualität als natürliche Schutzstoffe des Nadelbaumes bestimmen und den Widerstand gegen Insektenschäden in bestimmtem Maße bewirken.
1. . , , .2. . . , . , .3. , . , , , , , .
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6.
Bayley  A.D.  Kietzka  J.W. 《New Forests》1997,13(1-3):341-356
Two types of containerized P. patula seedlings, referred to as hard and soft seedlings, were raised by droughting and different fertilizer applications. Hard seedlings were raised by applying half the water and a quarter of the fertilizer (0.01 g per seedling 21%N:7.1%P:14.2%K) applied to the soft seedlings. At the end of the nursery cultural treatments the two types of seedlings were morphologically distinct. Hard seedlings had lower heights, height to root collar diameter ratios and seedling dry masses than soft seedlings, but mortality was similar for both seedling types when planted during seven different production periods within the planting season on three sites which differed climatically and geologically. Correlations between mortality and height to root collar diameter ratio (r = 0.76), root to shoot ratio (r = 0.83) and root growth potential (r = --0.69) were obtained indicating that grading of seedlings on these parameters may improve survival. However, it was evident that survival could be significantly improved by identifying the best time of year and conditions for planting, as well as improving stock quality.  相似文献   

7.
Summary The structure of the reducing end group in xylan can be written: --D-Xylp-(14)--D-Xylp-(13)--L-Rhap-(12)---D-GalpA-(14)-D-XylIn alkaline media the reducing xylose group is easily isomerized and removed by a -elimination which leads to a reducing galacturonic acid end group. The 1, 2-linkage between rhamnose and the galacturonic acid explains the retarding effect on the alkaline peeling. Even under fairly mild conditions the galacturonic acid group is converted to other groups which are very stable in alkaline media. Model experiments permit the conclusion that OH-3 in the reducing group is subjected to -hydroxyelimination. The 3-deoxy-2-O--L-rhamnopyranosyl-D-threo-hex-2-enuronic acid group formed is unstable in acid medium and escapes observation by the techniques employed for determination of the end groups.Upon prolonged alkaline treatment and increased proportion of these groups is lost and a rapid peeling proceeds until a xylose group with a 4-O-methylglucuronic acid substituent is liberated. The consecutive reactions of this group are similar to those of the galacturonic acid groups.The formation of 3-deoxyaldonic acid end groups, an important stopping reaction in cellulose, is of minor importance in xylan.The financial support from the 1959 Års Fond för Teknisk och Skoglig Forskning samt Utbildning is gratefully acknowledged.  相似文献   

8.
Aboveground and belowground root biomasses (Babove and Broot) were measured for young, isolated Rhizophorastylosa on Iriomote Island, Japan. The relationship between these two parameters was significant and given as the equation, Broot(g dry weight) = 0.394 × Babove(g dry weight) – 485 (r = 0.986). Multiple regression analyses also revealed good correlation between diameter and biomass of prop roots (Dprop and Bprop) and between prop root and root biomasses. Consequently, root biomass could be estimated from the measurements of diameter and biomass of prop roots using the multiple regression equation, Broot(g dry weight) = 80.0 ×Dprop(cm) + 0.86 ×Bprop (g dry weight) – 251. The relationship between DBH (diameter at breast height) and prop root biomass was also adequately described using an allometric equation.In Hinchinbrook Channel, Australia, redox potential (measured as Eh) and organic carbon stocks in the top 5cm of mangrove sediments were measured along a 600m transect from the frequently inundated, Rhizophora dominated zone on the creek edge, towards higher grounds, where Ceriops spp. became increasingly dominant. Eh values were about –60mV near the creek edge and increased to 260mV on higher grounds. Organic carbon stocks showed an opposite trend to Eh, with the values decreasing from about 360tCha–1 to 160tCha–1. At 18 sites, representing six different habitats, organic carbon stocks were also measured along with the DBH of mangrove trees. DBH was converted into aboveground biomass and then into root biomass using the equations obtained in the study on Iriomote Island. The average organic carbon stocks in the top 50 cm of sediments, aboveground biomass and root biomass were 296tCha–1, 123 tCha–1 and 52 tCha–1, respectively, and accounted for 64%, 25% and 11% of the total organic carbon stock.  相似文献   

9.
Data on stand structure and rates of photosynthesis were used to estimate net canopy carbon fixation and carbon accumulation as living biomass in mangrove forests in Hinchinbrook Channel, Australia. Total annual canopy net carbon fixation was estimated to be about 29tCha–1yr–1. This equates to about 204,000tCyr–1 for all mangrove forests in Hinchinbrook Channel. Of this, only about 12% was stored as living plant biomass. Although it is not yet possible to present a robust carbon balance for mangrove trees, the remainder is presumably lost through plant respiration, litter fall, root turnover and exudation of organic compounds from roots.  相似文献   

10.
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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11.
Xylan prepared from culms of kumaizasa (Sasa senanensis Rehd.), a representative species of bamboo grass, was hydrolyzed with-xylanase ofStreptomyces olivaceoviridis E-86. Four arabinoxylo-oligosaccharides and two glucuronoxylo-oligosaccharides were isolated from the enzymatic hydrolysate of the xylan by chromatography on a charcoal column, a Dowex 1-x8 column, a Toyo-pearl HW-40S column, and a LiChrospher 100 NH2 column and on preparative paper chromatography. The results of the structural analyses of the saccharides showed that the isolated oligosaccharides had the structures of 32--l-arabinofuranosyl-xylobiose, 32--l-arabinofuranosyl-xylotriose, 32--[-d-xylopyranosyl-(1 2)-l-arabinofuranosyl]-xylobiose, 33--[-d-xylopyranosyl-(1 2)-l-arabinofuranosyl]-xylotriose, 23--4-O-methyl-d-glucuronosyl-xylotriose, and 23--d-glucuronosyl-xylotriose. From the structural analysis of the oligosaccharides derived from the xylan, kumaizasa xylan was concluded to be a kind of arabinoglucuronoxylan having not only stubs of singlel-arabinose and singled-glucuronic acid but also stubs of disaccharide units such as-d-xylopyranosyl-(1 2)-l-arabinofuranose.  相似文献   

12.
Ohne ZusammenfassungEntomologe im U. S. Bureau of Entomology and Plant Quarantine.Die Arbeit erschien unter dem Originaltitel Aerosols for Insects.  相似文献   

13.
Summary A simple model for density distribution within an annual ring is proposed. The model originates from the concept that a tree has two growing modes early and late wood mode respectively and that during a growing season there is transition from the first to second. An annual ring is described by six parameters. The use of the model is discussed and a number of possible measures are suggested. The advantages and limitations of the model is also discussed.  相似文献   

14.
We investigated the physiological and psychological responses of ten healthy male volunteers to a single heavy floor-impact sound generated by dropping an automobile tire from heights of 50, 100, and 150cm in a wooden house. Blood pressure and peripheral blood flow were measured simultaneously, and sensory evaluation was conducted using the semantic differential method. The results obtained were as follows: (1) the systolic blood pressure increased and the peripheral blood flow decreased when the subjects heard the heavy floor-impact sound; (2) the heavy floor-impact sound caused the subjects to feel uncomfortable, but there was no significant change in sharp and monotonous feelings; and (3) for the heavy floor-impact sound for 100cm and that for 150cm, the subjects showed no difference in comfortable feeling, but we detected differences in the variations of both the systolic blood pressure and the peripheral blood flow.Part of this research was presented at the 48th Annual Meeting of the Japan Wood Research Society, Shizuoka, April 1998.  相似文献   

15.
Zusammenfassung Die Befallsstärke von Erdbeerpflanzen durch Blattälchen wird allgemein in Älchen je 20 g Herzen ausgedrückt. Man versteht unter dem Herz einer Erdbeerpflanze die Knospe, die jungen Blütenanlagen und die unentfalteten Blätter. Es besteht aber ein gewisser Ermessensspielraum in der Zuordnung zu gefaltet bis zu voll entfaltet. Meist ist die Knospe am dichtesten befallen. Der Durchschnittsbefall sinkt deshalb um so tiefer, je mehr nicht zur Knospe gehörende Pflanzenteile mituntersucht werden. Es handelt sich um die Frischgewichte der Herzen. Diese unterliegen Schwankungen je nach Jahreszeit, Erdbeersorte und Witterung. Ferner sind die Herzen stark befallener Pflanzen leichter als die gesunder Pflanzen. Im Durchschnitt wiegen im Frühjahr 30 Herzen 20 g. Es wird vorgeschlagen, die veränderliche Bezugsgröße 20 g Herzen durch das konstante Maß 30 Pflanzen oder 30 Rosetten zu ersetzen.
Summary On the isolation of bud and leaf nematodes (Aphelenchoides fragariae andA. ritzemabosi) from strawberry and chrysanthemum. Part II.The degree of infestation to strawberry plants by the leaf and bud nematodes is usualy expressed in nematodes per 20 g hearts. The heart of a strawberry plant includes the bud, the young inflorescences and the young closed leaves. A certain degree of judgement is requirred to distinguish between a closed leaf and an opened one. As the nematodes are usualy most concentrated in the bud, the degree of infestation is brought down by the inclusion of parts of the plant that do not directly belong to the bud.The weight of the hearts is also natably affected by weather conditions, season and plant variety. Furthermore heavily infested hearts are lighter than healthy ones. In spring, 30 hearts weigh approximately 20 g. It is suggested that the unstable measure of 20g hearts be substituted by the more reliable amount 30 plants or 30 rosettes.
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16.
Binderless particleboards were successfully developed from kenaf core using the steam-injection press. The effects of board density, steam pressure, and treatment time on the properties of the board were evaluated. The target board densities were relatively low, ranging from 0.40 to 0.70g/cm3. The properties [i.e., moduli of rupture (MOR) and elasticity (MOE) in both dry and wet conditions, internal bonding strength (IB), and water absorption (WA)] of the boards increased linearly with increasing board density. Steam pressure and treatment time also affected the board properties. The bending strength and IB were improved with increased steam pressure. A long steam treatment time contributed to low thickness swelling (TS) values and thus better dimensional stability. The appropriate steam pressure was 1.0MPa, and the treatment time was 10–15min. The properties for 0.55g/cm3 density boards under optimum conditions were MOR 12.6MPa, MOE 2.5GPa, IB 0.49MPa, TS 7.5%, and wet MOR 2.4MPa. Compared with the requirement of JIS 5908, 1994 for particleboard, kenaf binderless boards showed excellent IB strength but relatively poor durability.Part of this report was presented at the 19th Annual Meeting of the Japan Wood Technological Association, Tokyo, October 2001  相似文献   

17.
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   

18.
The concentration and molecular weight distribution of dissolved organic carbon (DOC) are reported for a mangrove creek in the Hinchinbrook area, Australia. DOC concentration ranged from 1.0mg Cl–1 near the creek mouth to 2.2mg Cl–1 at the innermost part of the creek. There was no apparent spatial trend in molecular weight distribution of DOC, with a >300gmol–1 fraction accounting for about 70% of the total in all samples. DOC concentration fluctuated between 0.5 and 1.2mg Cl–1 over one tidal cycle. The samples collected at low tide and during the rising tide were dominated by DOC of >300gmol–1 and <300gmol–1, respectively. This suggested the export of high molecular weight DOC, probably originating from litter leachates, and the import of low molecular weight DOC to the creek.  相似文献   

19.
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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20.
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.

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

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