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1.
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   

2.
One-year-old frozen-stored Norway spruce (Picea abies (L.) Karst.) container seedlings were planted in a controlled environment providing an air temperature of 22°C and soil temperature of 9±1 or 18±1°C. At planting the root plugs were either frozen or had been thawing for 4 days at 9°C. During a 5-week growing period, in both cold and warm soil the root growth and height growth were less in frozen-planted seedlings than in thawed seedlings. In addition, frozen-planting delayed bud burst and increased mortality. Soil temperature, however, had no effect on bud burst or mortality. Low soil temperature retarded root growth of seedlings thawed before planting but resulted in both retarded root growth and height growth if root plugs were frozen when planted. These results indicate that planting Norway spruce seedlings with frozen root plugs constitutes a considerable risk for successful forest regeneration at soil temperatures normally prevailing in Fennoscandia in spring or early summer especially if the soil is dry at the time of the planting.  相似文献   

3.
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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4.
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   

5.
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.

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6.
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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7.
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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8.
Zusammenfassung Samenuntersuchungen an 12 Eichenarten und -formen, 20 Birkenarten und 14 Ahornarten zeigten, daß die Samen der Eichen und Ahorne, nordamerikanischer Birken und Ahorne nordasiatischer Abstammung in der Ukraine praktisch von Schädinsekten nicht beschädigt werden, während der Samenertrag der heimischen durch Schadinsekten stark herabgemindert wird.Die Widerstandsstärke der Samen gegen Schädlinge ändert sich. nicht nur bei den verschiedenen Arten, sondern auch innerhalb der Bäume einer Art je nach ihrem physiologischen Zustand. Die Widerstandsfaktoren der Samen gegen Schädinsekten sind entweder anatomisch-morphologische Besonderheiten (Schalenstärke), oder das Vorhandensein von Schutzstoffen in den Samen oder beide zusammen. Besonders deutlich sind diese Faktoren in den Eicheln von Bäumen der nordamerikanischen Abstammung gegen Eichelrüssler ausgeprägt. Chromatographische Analyse der Auszüge aus den widerstandsfähigen Samen der Schmidt'schen Birke und des Eschenahorns zeigten, daß für die Rolle der Schutzstoffe die Phenolstoffe verantwortlich sind von denen z. B. die Chlorogensäure ermittelt wurde.
12 , 20 14 - , - , - - . . - / /, . - . , , , , .
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9.
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   

10.
We prepared carpet cleaners containing three wood oils extracted from Thujopsis dolabrata Sieb. et Zucc. var. hondai Makino, Chamaecyparis obtusa Endl., and Chamaecyparis taiwanensis Masamune et Suzuki and studied their effects on mites and perfumerists' impressions. The oil concentrations were set at 0.1%, 0.2%, 0.4%, 0.8%, and 1.6%. The effects on Dermatophagoides pteronyssinus Trouessart were investigated. The sensory evaluations were conducted by seven male perfumerists using the SD method and they were asked to describe freely their impressions of the scents. These results showed that: (1) all three types of wood oil had a significant effect on making D. pteronyssinus inactive at 0.1% concentration; and (2) the wood oil of T. dolabrata evoked refreshing, natural, rich, and intellectual feelings; C. obtusa oil evoked vivacious, rich, and intellectual feelings; and C. taiwanensis evoked refreshing, natural, rich, rough, masculine feelings. According to the test subjects, T. dolabrata evoked woody and earthy impressions; C. obtusa evoked woody, citrus, and pine-resin impressions; and C. taiwanensis evoked woody, citrus, and medical impressions. Many issues remain to be investigated, but the inclusion of wood oil in carpet cleaners offered both good mite control and a pleasant aroma to humans. This study suggests a new potential for using these wood oils.  相似文献   

11.
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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12.
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   

13.
The present work aimed to study the effects of high constant and alternating temperatures on the development and prey consumption by Dicyphus tamaninii Wagner (Het., Miridae) with Aphis gossypii Glover (Hom., Aphididae) as prey.Results showed that the predator was able to successfully develop and reach the adult stage, on average, after 20.1 () and 20.6 () days at a temperature of 30 ± 1 °C with A. gossypii as prey. On the other hand, it was not able to develop at 35 ± 1 °C, here all N1 instars used at the beginning of the experiments had died even before moulting to N2 instar. At alternating temperatures of 25/15 ± 1 °C, the predator reached the adult stage 23.7 () and 23.5 () days after egg hatching, whereas when the temperatures were increased to 35/22 ± 1 °C, it took a significantly shorter period: 20.6 () and 20.9 () days. In general, the highest mortality occurred during the first two nymphal instars. The total percentage mortality during development from N1 to adult stage was 30 % and 100 % at the constant temperatures 30 ± 1 °C and 35 ± 1 °C, respectively. At the alternating temperatures of 25/15 ± 1 °C, it was lowest with 16.5 %, while at 35/22 ± 1 °C, it was 20 %.The results of the experiments on prey consumption showed that an individual D. tamaninii consumed during its development to adult stage at 30 ± 1 °C an average of 442.2 (), 433.6 () aphids. At the constant temperature of 35 ± 1 °C, the average daily prey consumption started with 4 aphids and decreased continuously till it approached nil on the 9th day, where all predatory nymphs died. At the alternating temperatures of 25/15 ± 1 °C, the total prey consumption during development was, on average, 359.3 () and 297.0 () aphids, while at 35/22 ± 1 °C it was 348.5 () and 334.0 () aphids. The effect of the four temperatures on the prey consumption by D. tamaninii during the first 10 days after emergence was also studied. At a constant temperature of 30 ± 1 °C, a total of 446.4 () and 372.0 () aphids were consumed, compared to 40.6 () and 39.0 () at 35 ± 1 °C. At alternating temperatures of 25/15 ± 1 °C, the predatory adult consumed, on average, a total of 267.0 () and 207.0 () aphids. Increasing the temperature to 35/22 ± 1 °C resulted in a higher prey consumption by the adult predator, reaching 351.5 () and 267.7 () aphids over the same period.In conclusion, results indicated that D. tamaninii is a promising predator of the melon aphid at a temperature spectrum ranging from 15 ± 1 °C up to 35 ± 1 °C.  相似文献   

14.
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   

15.
For the first time soil solarization was investigated in Croatia both in the field and in the greenhouse in 1991, 1992, 1993 and 1994. For two months (July and August), the soil was mulched with transparent polyethylene (PE) sheets of 0.015 or 0.050mm thickness. Soil temperatures at depths of 5, 10 and 20cm were recorded daily. In order to assess nematode population densities, soil samples were analysed before mulching and at the end of the mulching treatment. The results of these experiments showed that soil solarization drastically reduced the population of plant-parasitic nematodes (Meloidogyne, Pratylenchus, Paratylenchus, Tylenchus, Tylenchorhynchus spp.) by about 97–100% at a depth of 10cm and 92–97% at a depth of 20cm in the field, while in the greenhouse, the population of plant-parasitic nematodes was reduced by about 89–100% at a depth of 10cm and 98–100% at a depth of 20cm.In the same experiments, the population of saprophytic nematodes in the field was reduced by about 86–90% at a depth of 10cm and 72–89% at a depth of 20cm. In the greenhouse, the population of saprophytic nematodes was reduced by about 87–97% at a depth of 10cm and 87–93% at a depth of 20cm. This data shows that soil solarization was less effective in the control of saprophytic nematodes, which is considered to be an advantage.  相似文献   

16.
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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17.
Ohne ZusammenfassungDer Originalaufsaß erschien unter dem Titel The house Fly can be eradicated in The Southern Planter im Mai 1948 in Richmond (Virginia, USA.).  相似文献   

18.
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   

19.
The effects of nitrogen (N) and phosphorus (P) rates, P source, and method of P application were tested on growth and nutrition of four clones of hybrid poplar (Populus trichocarpa Torr. & Gray×P. deltoides Bartr. ex Marsh or P. trichocarpa×P. maximowiczii A. Henry) in a plantation on Vancouver Island. Treatments were applied shortly after planting. Nitrogen (0, 500kgNha–1) was supplied as ammonium sulfate (AS); half of the AS was added at the start of the second growing season. Phosphorus (0, 100, 200kgPha–1) was supplied as triple super phosphate (TSP), rock phosphate (RP), or diammonium phosphate (DAP) and banded or broadcast. Over four growing seasons, stem volumes increased with AS and P additions. The effects of AS and P each were greatest when the other was also added. Volume was greater when P was applied at 100kgha–1 than in the P control and did not significantly increase further at 200kgPha–1. Phosphorus additions were more effective when added as TSP or DAP than when added as RP, but only in P100 and when banded. Banding increased volume when P was applied at 200kgha–1, but increases were significant only for DAP fertilized trees. Roto-tilling associated with the banding treatment also increased volume when AS and P were not added. Rankings of clones with respect to stem volume varied with N supply and changed over time.  相似文献   

20.
This study quantitatively compared the sapling (height 62–289cm) architecture and growth of Castanopsis cuspidata and Quercus glauca, both of which are major components in the temperate zone of western Japan, under shaded light conditions in secondary forest. When the sapling architectures were compared at the same support mass (trunk + branch mass), C. cuspidata had a larger crown area but a smaller height gain than did Q. glauca owing to the allocation of more biomass to lateral branches in C. cuspidata. The above-ground relative growth rate (RGR) of C. cuspidata (0.442gg–1 year–1) was nearly twice that of Q. glauca (0.256gg–1year–1), primarily as a result of a greater total leaf area per above-ground biomass (LAR) in C. cuspidata (56cm2g–1) as compared to Q. glauca (33cm2g–1). Because it has a disadvantage in height gain, related to its allocation pattern of biomass, C. cuspidata realized the same height growth (RGRH) as Q. glauca, despite the large biomass production. The great potential for photosynthesis in C. cuspidata, which results from its vigorous lateral spreading, is presumed to give it a long-term advantage over Q. glauca in the shaded forest understory. Q. glauca invests preferentially in trunk biomass, possibly giving it an advantage in sunny sites as opposed to a shaded forest understory.  相似文献   

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