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1.
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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2.
Summary For protection of agricultural crops, archards, forests and stored products a system of institutes for vegetative protection have been gradually built in Bulgaria within the last fifteen years. Now a leading part in the study of pests and diseases of plants are taking the Academy of Rural Economy Sciences and the Institutes for Plant Protection, for Forest Protection, the Zoological Institute by the Bulgarian Academy of Science, the Higher Rural Economy Institute and the Higher Forest Institute. Specialists of all ranks are working at these institutes: academicians, member correspondents, professors, senior and junior scientific collaborators and a great number of experts and assistants. Parallel with the studies of specific composition of pestilent insects, their biology is being explored and experiments are being made with insecticides. An inquiry is also being undertaken for utilization biologic combat against noxious insects. In aid of scientific institutes a dense network of services for heading the research work and combat on the terrain has been organized.
Résumé Pour la défense des cultures agricoles, des vergers, des forêts et des produits récoltés, un système d'instituts pour la défense végétale a été successivement dé veloppé en Bulgarie pendant les dernières quinze années. Actuellement l'Academie des sciences de l'economie rurale et les Instituts pour la défense végétale ont le rôle dirigeant dans les recherches de la nocivité et des maladies sur les plantes. Dans ces instituts travaillent des spécialistes de toutes les catégories scientifiques: des académiciens, des membres-correspondants, des professeurs, des travailleurs scientifiques supérieurs et plus jeunes, avec un grand nombre d'aides-spécialistes. Parallèllement à l'étude de composition specifique des insectes nuisibles on étudie sa biologie, de même on fait des expériences avec des insecticides. Aussi on cherche à utiliser la lutte biologique contre les insectes nuisibles. Pour faciliter les instituts scientifiques dans cette lutte et leur recherche sur le terrain, un immense service est organisé dans tous les plus grands emplacements peuplés du pays.

. , 15 , , , . . - , , , . - , , - . : , , , . , . . , . - , . .
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3.
Summary It is stated that in the spreading of epizooties among small wild animals, a factor of biocoenosis played a main role, first of all some phenomena among small rodents, the field mice. In the spreading of rabies infection, a role is ascribed to an insect, theNecrophorus vespillo.The author suggests a research work to be done in that respect, and perhaps in the regions where rabies was never registered and are still free of rabies, as to establish what in a such biocoenosis is lacking that could be a factor of rabies epizooty.
Résumé A l'extension de grandes épizooties chez les animoux féroces, on considère que le grand rôle joue le facteur de biocenose, tout d'abord certains phénomènes entre les menus rongeurs, souris de champs. On attribute surtout le rôle de l'extension de l'épizootie de rage à l'insectNecrophorus vespillo. On recommende de faire des recherches dans ce but avec les autres branches de sciences naturelles et peut-être dans ces regions du monde où il n'y en avait pas et il n'y a pas aujourd'hui de rage, pour établir ce qu'il manque dans une telle biocenose et que peut être pourrait on prendre en considération comme le facteur des épisooties de rage.

, — . Necrophorus vespillo L. . , .
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4.
Summary Present development of forestry entomology in the SSRThis article gives an outline on the occurrence of the more important harmful forest insects in the SSR in the year 1950–1962 and on the results of their study. The Norway spruce suffered from the year 1954 notably byIps typographus L. The control was based on insecticides, studies included optimal density of natural regeneration at the mass propagation etc. It was found, for instance, that typical density borings in bark (151–300 borings per 1 sq.m. of bark) shows variation in the shortest distance between borings from 54–70 mm. Relation between density of borings and their distance indicates function y = a.x–b, (constant a = 476,9 and constant b= 0,38). It was further found thatIps typographus L. shows even sister generations twice in a year (about 60%, eventually even 30% females of the preceding population). Sister laying is conditioned mainly climatically, i.e. also by the forest stand elevation above sea level. A secure control of further harmful species of Norway spruce,Trypodendron lineatum (Ol.) was carried out by extirpation of wintering beetles in soil, eventually by treating of round wood by emulsions on the HCH + DDT basis.Cephaleia abietis L. shows two diapause periods in a larval stage. For this reason, the development of this species lasts prevailingly two years (90% population). Swarming imagines are controlled by chemical aerosols (10% DDT in the dosis 4–8 kg/ha). On obtained from eggsTrichogramma cephalciae Hochm. et Mart. which cannot be grown on eggs of butterflies. Investigations found that the clean eating ofZeiraphera diniana Guen. begins at the density of 300 caterpillars per one meter of long branch. Chemical control (aerosol 10 l/ha) is recommended when feeding is repeated for three years. The mass propagation ofBupalus piniarinus L. appeared on the Scotch pine. The critical number amounts 400 caterpillars per one kg of needles.Hylobius abletis L. is controlled by insecticides in trap barks and by underground traps for concentration of egg laying. Oak was injuried mostly by the rollerTortrix viridana. The critical number is one caterpillar per one bud. Other, in the SSR new harmful insect of oakArchips crataegana (Hb.) showed the critical number 100 egg heaps on the stem to the height of 2 m. The eggs of the above mentioned species showedTrichogramma embryophagum cacoeciae March., which can easily be grown on butterfly eggs. Oak 60–200 years old was attacked byApethymus biaccatus (Gmel.) andA. abdominalis (Lep.). Silver fir was harmed mainly by the rollerChoristoneura murinana (Hb.). Also the critical number was found. Egg rearing gaveTrichogramma minutum Ril. Ash indicates new type of bark injuries caused probably by a representative of the genusLestes (Fig. 1.). Poplars are damaged by the species of the familyCerambycidae, further byCryptorrhynchus lapathi L. and by the species of the familyAegeridae. Saperda carcharias L. has in the Czechoslovak conditions a generation of three years. Eggs overwinter.Cryptorrhynchus lapathi L. has in the southern Moravia mostly (70% population) one year generation, the rest shows a generation of two years. Beech and hornbeaum were harmfully attacked byErannis aurantiaria Hb.) andColotois pennaria (L.). It is obvious that in the year 1950–1962 several species (Alchips crataegana (Hb.),Apethymus braccatus (Gmel.),A. abdominalis (Lep.) on oak,Erannis aurantiaria (Hb.) andColotois pennaria (L.) on. hornbeam and oak,Pachynematus scutellatus Htg. on Norway spruce etc.) previously not known as important forest injurious insect, appeared as calamity species. Further it is obvious that some harmful insects probably under the influence of changed structure and also forest stand microclimate are retreating whereas other species show mass outbreak. For this reason it is necessary to study the lawfulness of the propagation of the individual species.
Résumé Les plus récentes expériences de l'entomologie en TchécoslovaquieLe travail contient un aperçu concernant la présence d'insectes nuisibles forestiers de certaine importance en Tchécoslovaquie au cours des années 1950–1962 ainsi que le résultat de leur recherche. Jusqu'à 1954 l'épicéa a été assaili surtout par l'Ips typogiaphus L. On cherche une solution de la défense au moyen des insecticides, la densité optimale d'attaque en cas de la reproduction excessive etc. Par exemple il a été constaté que lors de la densité typique de forage de l'écorce (151–300 forages par mètre carré d'écorce) leur distance ré ciproque varie de 54 à 70 mm. Le rapport entre la densité de forage et de leurs distances présente la forme de fonction y = a.x–b, où la constante a = 476,9 et la constante b = 0,38. Ensuite il a été constaté qu'en ce qui concerne l'Ips typogiaphus L. existent même deux gé nérations-soeurs au cours de l'année (environ 60 % respectivement encore 30 % des femelles de la population pécédente). La production de pondaisonsoeur est soumis surtout au facteurs climatiques, c'est à dire même á l'altitude des peuplements. Contre un antre parasite de l'épicéa, leTrypodendron lineatum (Ol.), une certaine défense fut élaborée par l'extermination d'imagos hivernant dans le sol ou par le traitement de rondin par des émulsions sur la base HCH + DDT. En ce qui conceme laCephaleia abietis L. on a constaté deux phases de diapause en état de larve. C'est pourquoi le développement duparasite est en majorité biennal (90% de la population). II a été introduit une lutte chimique contre l'essaimage d'imagos par des aerosols (10% de DDT dans une dose de 4 à 8 kg par ha). On a réussi à faire sortir des oeufs de laTrichogramma cephalciae Hochm. et Mart. que l'on ne peut pas cultiver sur les oeufs de papillons. En ce qui concerne laZeiraphera diniana Guen. il fut constaté que la défoliation compléte a lieu par 300 chenilles sur une branche d'un métre de longueur. La lutte chimique est recommandée en cas d'attaque repétée au cours de trois ans. Sur des pins il fut constaté la multiplication de masse duBupalus piniarius L. où le chiffre critique et atteint par 400 chenilles sur un kg d'aiguilles. En ce qui concerne l'Hylobius abietis L. on élabora une manière de défense en utilisant des insecticides dans des pièges d'écorce et des pièges souterrains pour saisir les pondaisons. Sur le chêne c'était laTortrix viridana qui a causé les plus grands dé gâts. Le chiffre critique est exprimé par une chenille pour un bourgeon. En ce qui concerne l'ulté rieur parasite de chêne nouvellement apparu en Tchécoslovaquie, l'Archips crataegana (Hb.), le chiffre critique fut fixé par 100 agglomérations ovulaires sur le tronc jusqu'à 2 mètres de hauteur. On a obtenu laTrichogramma embryophagum cacoeciae March., qui peut être facilement cultivée sur les oeufs de papillons. Sur les chênes d'un âge de 60 à 200 sont apparus ensuite comme parasite desApethymus braccatus (Gmel.) et desApethymus abdominalis (Lep.). Sur le sapin apparaît surtout laChoristoneura murinana (Hb.). Un chiffre critique fut fixé. On a obtenu à partir des oeufs laTrichogramma minutum Ril. On a découvert sur le frêne un nouveau type de lésion de l'é corce provoqué vraisemblablement par la libellule g.Lestes (Fig. 1). Les capricornes, leCryptorrhynchus et lesSesia spp. sont nuisibles aux peupliers. En Tchécoslovaquie laSaperda carcharias L. a une géneration triennale. Les oeufs hivernent. LeCryptorrhynchus lapathi L. a en Moravie du Sud en majorité (70% de la population) une génération annuelle, le restant, biennale. Ensuite sur le hêtre et sur le charme a eu lieu l'apparition désastreuse de la chenille arpenteuseErannis aurantiaria (Hb.) et de laColotois pennaria (L.). Il en ressort donc qu'au cours des années 1950–52 plusieurs espèces ont fait une apparition désastreuse:Archips crataegana (Hb.),Apethymus biaccatus (Gmel.),Apethymus abdominalis (Lep.) sur le chêne,Erannis aurantiaria (Hb.) etColotois pennaria (L.) sur le charme et le hêtre, lePachynematus scutellatus Htg. sur l'épicéa et d'autres qui é taíent auparavent inconnus comme parasites considérables de la forêt.On peut en déduire qu'évidemment sous l'influence de la structure transformée et par consé quent du microclima des peuplements, certains parasites tendent à disparaître, tandis que d'autres insectes deviennent parasites désastreux. C'est pourquoi une recherche approfondie des lois de la reproduction en masse des différentes espèces est nécéssaire.

- 1950–1962. . 1954. Ips typographus L. , , . . , (151–300 1 2 ) 54 70 . y = a x–b, a = 476,9 b = 0,38. , Ips typographus L. ( 60%, 30% ). , . . . Trypodendron lineatum (01.) , HCH + DDT. Cephalia abietis (L.) , (90% ). (10% 4–8 (). Trichogramma cephalciae Hochhm. & Mart., . Zeiraphera diniana Guen. 300 1 . . . ( 10 /) . Bupalus piniarius L., 1 400 . Hylobius abietis L. . Tortrix viridana L. 1 1 . , ,Archips crataegana (Hb.) 100 2 . Trichogramma embryophagum cacoeciae March., . 60–200 Apethymus braccatus (Gmel.) Apethymus abdominalis (Lep.). Choristoneura murinana (Hb.). . Trichogramma minutum Ril. - Lestes (. 1). , .Saperda carcharias L. . .Cryptorrhynchus lapathi L. (70% ) , . Erannis aurantiaria (Hb.) Colotois pennaria (L.). , 1950–1962. (Archips crataegana (Hb.),Apethymus braccatus (Gmel.),Apethymus abdominalis (Lep.), Erannis aurantiaria (Hb.) Colotois pennaria (L.), Pachynematus scutellatus Htg. . .), . , , . .


Herrn Prof. Dipl.-Ing. Dr. A. Pfeffer zum 60. Geburtstag gewidmet.  相似文献   

5.
The relationship between physical hydrodynamic processes and nutrients dynamics was investigated in Mida creek, a groundwater influenced mangrovefringed creek in Kenya between March 1996 and May 1997. The research involved spot and timeseries measurement of nitrate–nitrite, ammonia, silicates, phosphates, salinity, temperature, sealevel as well as tidal currents at seven stations located in the front, middle and backwater zones of the creek. Groundwater level as well as total dissolved solids' concentration, salinity, temperature and nutrients' concentration were also measured once every month in shallow wells (watertable<5m) located in the upper region of the creek. Results of the study show that nutrient concentrations vary with the tide and that, though there is no river drainage, they are of the same magnitude as in mangrove creeks with substantial river runoff. The peak concentrations of NH 4 + –N (5.45M), NO 2 –NO 3 (5.63M), PO 4 3– –P (0.58M) and SiO 3 2– –Si (81.36M) in the creek occurred during flood tide, 2–3h before high waters. The (NO 2 + NO 3 )–N concentrations declined rapidly during ebb tide, reaching the minimum levels during low water. Contribution of groundwater seepage to the net nutrients flux (particularly on nitrite–nitrates) is largest in dry seasons. The study shows that groundwater outflow sustains the mangroves during periods of severe salinity stress and nutrients deficiency in dry seasons. This is essentially by limiting salinity increase and by boosting nutrient supply in dry seasons.  相似文献   

6.
Predicting field performance using seedling quality assessment   总被引:2,自引:0,他引:2  
Mattsson  A. 《New Forests》1997,13(1-3):227-252
Seedling quality is defined as fitness for purpose. Attributes for assessing seedling quality are grouped in material attributes that can be rapidly assessed by any number of direct or indirect methods, and performance attributes that are assessed by subjecting whole seedlings to certain environmental regimes and evaluating their growth response. Material attributes comprising morphology, bud dormancy, water relations and nutrition and performance attributes comprising frost hardiness, vigour and root growth potential are discussed with regard to relevance for predicting field performance. Measurement techniques and relevance in assessing seedling quality are presented for different physiological attributes: electrolyte leakage, enzymatic activity, water potential, water conductance, mineral nutrition, food reserves, mitotic index, gas exchange, chlorophyll content, plant growth regulators, stress-induced volatile emission, and nuclear magnetic resonance. Methods with future potential in improving the prediction of field performance are identified and discussed. The methods presented in this respect are chlorophyll fluorescence, infrared thermography, machine vision systems, integrated approaches and ecophysiological evaluations.  相似文献   

7.
Zusammenfassung Die SalatwurzellausPemphigus bursarius (L.)(Aphidoidea, Pemphigidae) gehört wegen ihrer unterirdischen Lebensweise zu den schwer bekämpfbaren Schädlingen, die in Salatkulturen regional starke Schäden verursachen können und von zunehmendem Interesse sind. In einem Befallsgebiet in Wolfenbüttel bei Braunschweig werden daher mehrjährige Untersuchungen zur Ermittlung der Bedeutung und geeigneter Bekä mpfungsmöglichkeiten der Salatwurzellaus durchgeführt. Bisher können über das Auftreten und die Bedeutung dieses Schädlings folgende Aussagen gemacht werden: Es besteht kein ursächlicher Zusammenhang zwischen dem Auftreten der Salatwurzellaus und zweier Salatvirosen (Salatmosaikvirus und Gurkenmosaikvirus). Sie alle traten unabhängig voneinander auf. Im Untersuchungsgebiet überwintertP. bursarius ausschließ lich an Pappeln, nicht dagegen im Ackerboden oder an Wurzelresten. Die Anfälligkeit verschiedener Salatsorten gegenüberP. bursarius ist nach den bisherigen Ergebnissen an 30 Sorten recht unterschiedlich, wobei die Sorten Hilmar, Kordaat, Unico, Kloek, Viktoria und Winter Butterkopf einen geringen oder gar keinen Befall zeigten, während die Sorten Wunder von Voorburg, Kagraner Sommer und Winter Mombacher stark befallen wurden. Diese Versuche müssen weitergeführt werden, bevor eine abschließende Beurteilung möglich ist. Die Schäden durch die Virosen, speziell das Salatmosaikvirus, sind in den Salatkulturen wesentlich schwerwiegender als die durchP. bursarius verursachten Verluste. Über Bekämpfungsversuche wird später berichtet.
Summary The lettuce root AphidPemphigus bursarius (L.)(Aphidoidea, Pemphigidae) belongs to the difficult controlable pests because of their subterranean mode of life. In lettuce cultures of certain regions this aphid can cause serious damages and therefore it is of increasing interest. In an area severely attacked byP. bursarius at Wolfenbü ttel near Braunschweig investigations are going on for several years to get to know the importance of this insect and to find out appropriate possibilities for its control. Up to now the following statements can be made concerning the appearance and the importance of this pest: There is no causal association between the lettuce root Aphid and two viroses of lettuce (lactuca virus 1 and cucumis virus 2). These pests appear independent from each other. In the investigated areaP. bursarius does hibernate only on poplars but not in the soil or on remaining roots. According to the hitherto existing results of 30 lettuce sorts the susceptibility of the various sorts againstP. bursarius is very different. The sorts Hilmar, Kordaat, Unico, Kloek, Viktoria and Winter Butterkopf did show a low or no attack, during the sorts Wunder von Voorburg, Kagraner Sommer and Winter Mombacher were severely attacked. These experiments must be continued before a definitive decision is possible. The damages in the lettuce cultures caused by the viroses, especially by lactuca virus 1, are more serious than those caused byP. bursarius. The control experiments are reported later.
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8.
We analyzed current forest operations in Toei, in the Okumikawa Forestry Area, Japan, by examining actual achievement, location, and topography. We considered five basic forest operations conducted by the Forest Owners Association between 1991 and 2000 in a subsidized reforestation and silviculture project: planting, weeding, pruning, cleaning, and thinning. In addition, we considered the road network, including public, forest, and strip roads. The area in which forest operations have been conducted over the past 10 years amounted to less than two-thirds of the area targeted in the Toei Forest Improvement Plan. The mean access distance of the work sites was 164m, which was 52m less than the 10-year average for the whole forest (216m). Forest operations tended to ignore remote forest areas where the topography was steep, due to cost, the logging techniques required, and labor requirements. We determined that the limitations on forest operations in Toei were a 300m access distance, an elevation of 800masl, and a 90% slope. In accessing work sites, the utilization ratios of forest and strip roads were higher than their composition ratios, and public roads were used most. Newly constructed strip roads were used more than forest roads. Based on current forest operations, we calculated the road density and length required to be 7.1m/ha and 79.2km, respectively, with an estimated cost exceeding 720 million yen for new construction.  相似文献   

9.
Summary During the years 1959–1961 the number of generations was followed in Spinach Leaf Miner (Pegomyia hyoscyami betae Curt.) in central Bohemia at 310 m above sea level and in the year 1961 in southern Bohemia at 450 m. The larvae and the eggs were studied on the leaves at regular 10–14 days' intervals by controlling each plant and images by means of a sweeping method. There have been acertained two generations in the year 1959 and three generations in the year 1961 in central Bohemia and two generations in the year 1961 in southern Bohemia. The occurence of every generation of larvae on the suggar-beet was separate and the previous and the consecutive generation did not overlop.The origin of the erroneous date on 6–7 generations of this species (Rambousek, Neuwirth, 1931) has been also cleared up in this article. This statement has been taken over by Sorauer (1953) from the Review of Applied Entomology (1931) and has been lately mentioned by many authors. F. Neuwirth gave a personal information, that the statement on 6–7 generations occurence of Spinach Leaf Miner has been found on the basis of theoretical calculation (from the lenght of one generation in spring and not on the basis of the facts found in natural conditions).
Résumé En 1959–1961 le nombre des générations de la mouche de la betterave a été observé dans la Bohème Centrale á l'altitude de 310 m audessus de la mer et en 1961 dans le Sud de la Bohème á l'altitude de 450 m. Les larves et les oeufs ont été observé sur les feuilles dans les intervalles de 10–14 jours regulierement effectués sur chaque plante et imagines en particulier par le filet fauchior. En 1959 deux générations et en 1960 et 1961 trios géné rations dans la Bohéme Centrale, ainsi que en 1961 deux générations dans le Sud de la Boheme ont été constates. La prence de chaque génération des larves sur la betterave aété separée et les générations consecutives ne malaient pas presque jamais avec les précedents.Dans cet travail l'auteur a clarifié comment une donnée fautive sur 6–7 générations de cette espéce est survenu (Rambousek et Neuwirth, 1931). Cette donnée orginante de Review of Applied Entomology [1931] a été reprise par Sorauer (1953) et elle a été ensuite récemment mentionée par d'autres auteurs. Selon une déclaration personelle de Mr. F. Neuwirth les donées des 6–7 générations de la mouche de la betterave en Tschécoslovaquie ent été acquis par une évaluation théoretique (se basant sur la durée de la génération du printemps et non sur les resultats des observations réelles dans les conditions naturelles.

1959–61 . (310 . ) 1961 . (450 . ). 10–14 , . 1959 . 2 , 1960 . — 3, 1961 . — 2 . , . , 6–7 (Rambousek, Neuwirth 1931). . . 6–7 , , .
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10.
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   

11.
Zusammenfassung 1. Es wurden Hydroponikkulturen der Ziernessel mit 11 verschiedenen Insektiziden (Chlorierten Kohlenwasserstoffen, Phosphorsäureestern und Carbamaten) behandelt.2. Die Insektizide wurden bei bewurzelten und unbewurzelten Sprossen über die Nährlösung appliziert und nach verschieden langer Dauerkultur Extrakte von Blättern, Sprossen und Wurzeln auf ihre insektizide Wirkung im Biotest(Drosophila melanogaster) überprüft.3. Allgemein war die Kontaktwirksamkeit der Wurzelextrakte hoch, während Sproß- und Blattextrakte nur bei systemischen oder ähnlich wirkenden Mittein Wirkungen beobachten ließen. Hierbei erwies sich das Carbamat Isolan als besonders blattwirksam.4. Durch Vergleich mit Kontrollextrakten unbehandelter Pflanzen konnte eine unterschiedliche Maskierung der WS durch die Lipoide gezeigt werden. Blattlipoide waren erheblich wirksamer bezüglich der Abfangpotenz als Wurzelextrakte.5. Da jedoch diese Kontrollextrakte eine Eigentoxizität fürDrosophila beobachten ließen, wird die Beachtung solcher Störwirkungen gefordert und auch bei Modellversuchen, wie den hier angestellten, eine Reinigung der Extrakte vor den Biotesten vorgeschlagen.
Summary Bioassay with crude plant extracts(Coleus blumei) after basal treatment with insecticides in hydroponic culture resulted differenciated contact activity. 11 insecticides (and acaricides) have been investigated in commercial formulation (emulsion and wettable powder, application of different concentrations via mineral salt solution). Apical treatment with insecticides (spray- application) will be reported in later papers.Leaf, stem and root of isolatedcoleus developed contact reactions in extracts forDrosophila melanogaster M. (Rutshurel, sensitive and Göttingen, sensitive). Leaf-extracts after basic treatment with Isolan, Parathion, Diazinon, Demeton-o-methyl and Malathion caused high contact effects. Lower intensities are recovered in leaves after application (via roots) of Lindane and Trichlorphon (Dipterex®). Additions of DDT-formulations and Phenkapton are causing poisoning action of root extracts only and Chlorobenzilate was not effective onDrosophila. All other insecticides showing high poisoning in root extracts, resulted insecticidal actions in stem extracts regarding the degree of systemic properties. Thiodan is less active in that response than Lindane and the typical systemic substances as Isolan, Demeton-o-methyl etc.Some of the reactions could be regarded as well as action of the insecticidal substance as possible effect of formula. The bioassay of pesticides residues in crude extracts is serviceable under certain circumstances. It is proposed that better and more instructive information should be obtained by tracer-substances or by cleaning and separating procedures of the extracts (chemical methods) and subsequent bioassay.
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12.
A study was carried out in an alley cropping system in the Eastern Maize Belt of the United States with the objective of quantifying the competition for water between trees (black walnut (Juglans nigra L.) and red oak (Quercus rubra L.) and maize (Zea mays L.). Spatial and temporal variation in soil moisture, tree and maize rooting patterns, tree and maize water uptake, and maize leaf area expansion were determined in three treatments; barrier (polyethylene root barriers separating maize and tree roots), trench (trenching without a polyethylene barrier), and no barrier (control). Significant temporal variation in soil moisture was observed in both black walnut and red oak alley cropping systems. The barrier and trench treatments resulted in higher soil moisture in the maize alley and lower soil moisture in the tree row than the no barrier treatment. Uptake of water by maize was higher in the barrier than the no barrier treatment. However, tree water uptake was higher in the no barrier treatment than in the barrier treatment because tree roots utilized water from the maize alley. Maize leaf area was negatively impacted by water stress in the no barrier treatment. Quantification of rooting patterns revealed that maize and tree roots were concentrated in the top 30 cm soil layer where water fluctuations were greatest. The barrier and trench treatments successfully eliminated the belowground root competition between trees and maize and resulted in greater leaf area and higher grain yields than the no barrier treatment. Thus, competition for water rather than competition for light seems to be critical in defining the productivity and sustainability of this alley cropping system.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

13.
Summary That the behavior of wood in service results from its structure is generally accepted by wood scientists. No doubt this acceptance is due to the broad interpretation of such a term. Structure can refer to the organization of elements on a macro scale, such as in a laminated beam, as well as to the arrangement of cellulose molecules in the crystalline region of an elementary fibril.This presentation focuses on a structural domain that appears increasingly to be a critical one in wood behavior-ultrastructure. The spectrum of terminology that has been used in profusion during the electron microscopic era must first be defined so that confusion is minimized. Then a historical evolution of the field of wood ultrastructure can be presented to provide perspective. Structures that have been shown to affect or indeed to control certain processes can be identified. The role of a non-structure, the elusive transient capillary, can be illustrated. Microfibrillar organization and cell wall archictecture fall into the realm of ultrastructure as well.The past decade of research in wood science has been productive to a significant extent because of scanning electron microscopy and its accessory tools and techniques. The exploration of wood penetration by wood preservatives, pulping liquors and coatings using this approach has yielded much new evidence. One can speculate about the anticipated contributions of computer-driven SEM, stereology, STEM, and even higher resolution microscopy in the near future.  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).
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15.
Zusammenfassung In dem für die Besonderheiten der Kiefernrindenwanze konstruierten Olfaktometer, wurden die Chemotaxie des Schädlings auf die Terpenoide aus ätherischen Ölen der Gemeinen Kiefer untersucht. Es wurden dabei Terpenoide mit vorwiegend anlockender und abschreckender Wirkung isoliert. Einige Terpenoide (-Pinen und Limonen) verwandeln bei einer Änderung ihrer Konzentration ihre anlockenden Eigenschaften in abschreckende. Bei der Verdampfung von der Oberfläche der pflanzlichen Gewebe der Kiefer bilden die Terpenoide eine Schutzwolke — ein äußeres Schutzsystem (R-System). Bei Überwiegen der anlockenden Stoffe wird in den Dä mpfen der wirksamen Stoffe das System lockend (A-System). Es wurde ein Modell des äußeren Systems aufgebaut und ihre ungefähre mathematische Erklärung gebracht, die erlaubt, die Anlockung der pflanzlichen Gewebe der Kiefer für die Rindenwanze nach den Ergebnissen der chromatographischen Analyse der atherischen Öle zu ermitteln. Das äußere Schutzsystem der Kiefer ist eines von den Systemkomplexen, welches als Schutzfunktion die Widerstandfähigkeit der Kiefer gegen Schadinsekten erfüllt und gewährleistet.
, , .- , . /-, / . , , , /R- /, /A-/. , . .
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16.
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   

17.
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   

18.
210Pb, 234Th and 7Be activities were measured to establish sediment accumulation rates, estimate sediment mixing rates, and determine the depth of the sediment mixed layer in the Sepetiba Bay mangrove ecosystem near Rio de Janeiro City, Brazil. Three sediment cores were collected from Enseada das Garças, a typical exposed tidal flat region with a sequence of sedimentary features. The seaward edge of this sequence is a mud flat with the landward portion covered with Spartina alterniflora followed by mangrove vegetation. An additional core was collected on an overwash island near Barra de Guaratiba, which is cover with mangroves without a mud flat or Spartina alterniflora sequence. Sediment accumulation rates were determined to range up to 1.8cm/yr with the Spartina alterniflora having the maximum rate. Mixing rates were estimated for the Spartina alternifloracore at 40cm2/yr based on 210Pb and 7Be from the upper mixed region of the core. The 234Th activity in this core suggested that either mixing or the input of 234Th were not in steady state. The sediment mixed region depth ranged from 4cm to greater than 30cm. At the Enseada das Garças site the mixing depth decreased in the landward direction (i.e. mud flats > 30cm, Spartina alterniflora 11cm, mangroves 4cm). Along with this decrease in sediment mixing depth was a shift from physical to biological mixing. The Barra de Guaratiba core had a sediment mixed layer of 13cm as a result of physical and intense biological activity.  相似文献   

19.
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   

20.
Summary It is demonstrated that there can be only one driving potential for the movement of water through wood and this will be a function of wood state. On the assumption that the driving potential is the partial pressure of water vapour, a theoretical expression is derived for the diffusion coefficient. Such expression is fitted to diffusion coefficients for Scots pine and a remarkably good fit is obtained.Symbols a reciprocal mean radius of curvature of a capillary meniscus; also taken to be the radius of the corresponding exposed liquid surface, m - b spacing between flow paths in the cell wall, m - D diffusion coefficient for water in wood with vapour pressure as the driving potential, kg/ms Pa - Da diffusion coefficient for water vapour through air, kg/ms Pa - D diffusion coefficient for water in wood with the driving potential - D diffusion coefficient for water in wood with the driving potential - D0 diffusion coefficient for water in wood with vapour pressure as the driving potential, which is associated with leakage paths through the wood, kg/ms Pa - Df diffusion coefficient for water in wood with vapour pressure as the driving potential, corresponding to fibre saturation and with no leakage paths, kg/ms Pa - Dc diffusion coefficient for water in wood with vapour pressure as the driving potential, which is associated with the constriction of the vapour flow as it approaches the cell wall, kg/ms Pa - D diffusion coefficient for water in wood with moisture content as the driving potential, kg/ms - diffusivity for water vapour in air, m2/s - F flux of water, kg/m2 s - p partial pressure of water vapour, Pa - R specific gas constant for water, J/kg K - r fractional relative humidity - T temperature, K - x length coordinate in direction of flow, m - the dimensionless ratio Df/Dc evaluated at r=1/e - arbitrary driving potential for movement of water in wood - cell spacing in the direction of water flux, m - density of liquid water, kg/m3 - coefficient of surface tension, N/m - arbitrary driving potential for movement of water in wood - fractional moisture content  相似文献   

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