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1.
I investigated seasonal changes in the relationships between brood size, body mass of nestlings and body mass of parents of the bull-headed shrike, Lanius bucephalus, in Ishikari, northern Japan. When the broods were 12days old, the body mass of the heaviest nestling in a brood did not differ among brood sizes, or throughout the season. However, the body mass of the lightest nestlings in a brood was different among brood sizes. The body mass of the lightest nestling in five- and six-nestling broods decreased throughout the season. The lightest nestling in four-nestling broods, and the lightest and the second lightest nestlings in five-nestling broods, were significantly lighter than the heaviest nestling in broods of this size. It is likely that pairs with six nestlings at 12days old can feed at least five of these nestlings enough to ensure their survival . The standardized body mass of parents (SBM), which was defined as the body mass divided by the length of the tarsus, did not differ among brood sizes, or throughout the season. It is possible that the relationship between the constancy of the SBM and the seasonal decline in the body mass of nestlings indicates that bull-headed shrikes have a limit to their parental efforts.  相似文献   

2.
Tim S. Stuart  Hans Gaffron 《Planta》1971,100(3):228-243
Summary In our earlier work we have shown that hydrogen photoproduction by photosystem I of Scenedesmus does not require O2 evolution or cyclic photophosphorylation but must be due to non-cyclic electron flow from organic substrate(s) through photosystem I to hydrogenase, where molecular H2 is released. The kinetics of this reaction are rather complex, in that H2 photoproduction by Scenedesmus evidently occurs in two phases: a rapid initial phase which depends upon the dehydrogenation of a pool of H donors, and a later and slower second phase which is limited by the flow of electrons from fermentation. When adapted cells were incubated in the dark with an inhibitor (Cl-CCP or salicylaldoxime), the pool utilized by photosystem I gradually disappeared. However, the pool gave a rapid rate of hydrogen photoproduction when the adapted cells were illuminated immediately after adding the inhibitor. The rate at which the pool was utilized depended upon the light intensity and was not light-saturated at the highest intensity tested (3.4×103 W cm-2).With light of at least medium intensity (1.67×103 W cm-2), the pool was rapidly exhausted and the reaction became dependent upon the leak of electrons from fermentation. The size of the leak was found to depend upon the level of reduced organic compounds in the cell, since this process was depressed by starving the cells and was much enhanced by adding glucose or by growing the cells heterotrophically. A quantitative relationship was found between the amount of glucose added and the resulting stimulation of H2 photoproduction, in that one mole of glucose gave about 0.5 mole of H2 gas.The following abbreviations were used: Cl-CCP=carbonyl cyanide m-chlorophenylhydrazone; DCMU=3-(3,4-dichlorophenyl)-1,1-dimethylurea; DCPIP=dichlorophenol-indophenol; PS=photosystem.These studies were supported by contract No. AT-(40-1)-2687 from the U. S. Atomic Energy Commission.  相似文献   

3.
Summary A comparative study of the antitumor effect of murine recombinant interferon() Mu-rIFN() and murine recombinant interferon() Mu-rIFN() on B16-F10 melanoma was conducted. Administration of Mu-rIFN() i.p. into C57BL/6 mice on days 1 to 7 produced a higher suppressive effect than Mu-rIFN() both on the growth of s.c. implanted tumor and on the formation of artificial pulmonary metastasis. Pharmacokinetic study of Mu-rIFN() demonstrated that high plasma levels were retained for a long time. In clonogenic assay, Mu-rIFN() at 1000 units/ml showed about 80% inhibition of colonies of B16-F10 melanoma. However, Mu-rIFN() hardly inhibited the colonies, even at 1000 units/ml. Augmentation of natural killer (NK) cytotoxicity was much greater with Mu-rIFN() than Mu-rIFN(), whereas Mu-rIFN() enhanced the cytotoxicity of peritoneal macrophages more strongly than Mu-rIFN(). Injection of Mu-rIFN() i.p. 1 day before tumor challenge also inhibited the formation of pulmonary metastasis of B16-F10 melanoma. However, pretreatment of mice with carrageenan significantly suppressed the inhibitory effect of Mu-rIFN(). From these results, it is suggested that the inhibitory effect of Mu-rIFN() on the tumor growth and metastases of B16-F10 melanoma is mediated partly by direct antitumor effect and partly by the activation of macrophages, and that the augmentation of NK activity contributes mainly to the antitumor effect of Mu-rIFN().  相似文献   

4.
Zusammenfassung Der Verlauf des Nahrungsflusses im Darmtrakt der Kleinzikade Euscelidius variegatus wird nach Verfütterung von farbstoffhaltiger Nährlösung ermittelt. Es wird der Beweis erbracht, daß die aufgenommene Nahrungsmenge in der Filterkammer geteilt wird und die beiden Anteile den Darmtrakt auf zwei verschiedenen Wegen in Richtung Rektalblase passieren. Ein Anteil der aufgenommenen Nährlösung wird über einen Kurzschlußweg in der Filterkammer sowohl über den Filterkammerdarm als auch über die Kryptonephridien direkt in den Enddarm gepumpt, während die in der Magentasche der Filterkammer verbleibenden Nahrungsanteile über einen langen Verdauungsweg zum After gelangen. Hierbei wird der Magentascheninhalt in den Magen gedrückt. Von dort aus passiert er den Mitteldarm und erreicht über den Enddarm den After. Der Kurzschlußweg und der Verdauungsweg können gleichzeitig benutzt werden. Der Kurzschlußweg wird von der Nahrung jedoch in viel kürzerer Zeit durchströmt als der längere Verdauungsweg.
The directions of the flow of food in the alimentary trad of the leafhopper Euscelidius variegatus KBM. (Jassidae)
Summary The leafhopper Euscelidius variegatus is fed with synthetic food, coloured with 1% Azorubin-S. Its flow in the alimentary tract has been studied. It has been found that the sucked-in food is divided into two parts in the filter chamber, each taking different way in the alimentary tract for its flow. One part of the food is pumped into the hindgut via the short circuit way going through the filter chamber once over the Filterkammerdarm and also over the kryptonephries. That part of the food, which remains in the pocket of the filter chamber takes the long digestion way to the anus over stomach, midgut and hindgut. Both the ways could be used at the same time. But the food takes much shorter time for its passage through the short circuit way as compared to the time needed for the long digestion way.
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5.
Summary Intestinal lipid absorption and transport were investigated in albino rats. The observations point towards the existence of a continuity between plasma membrane invaginations and elements of the Golgi complex on its mature face. They also suggest a segregation of lipid droplets by paired Golgi membranes and plasma membrane invaginations. The following way for lipid transport is deduced: lipid droplets moving inside the smooth endoplasmic reticulum accumulate progressively and are condensed in Golgi cisternae of the forming face. Their limiting membrane ruptures and liberated lipid droplets are segregated by paired Golgi membranes of the mature face or by plasma membrane invaginations. Subsequently the inner of the two segregating membranes disappears while the lipid droplet is moved towards the intercellular space inside a canal communicating with this space. The suggestion is made that the Golgi apparatus is of double origin: one component representing a terminal plication of the endoplasmic reticulum; the second one—a terminal plication of the plasma membrane invagination. This concept explains the ultrastructural and histochemical differences between Golgi membranes of the forming and mature faces of the complex.  相似文献   

6.
A defined set of oligosaccharides and glycopeptides containing -linked fucose were used to examine the specificity of the immobilized fucose-binding lectin Lotus tetragonolobus agglutinin (LTA1), also known as lotus lectin. Glycans containing the Lewis x determinant (Lex) Gal1-4[Fuc1-3]GlcNAc1-3-R were significantly retarded in elution from high density LTA-Emphaze columns. The lectin also bound the fucosylated lacdiNAc trisaccharide GalNAc1-4[Fuc1-3]GlcNAc. The lectin did not bind glycans containing either sialylLex or VIM-2 determinants, nor did it bind the isomeric Lea, Gal1-3[Fuc1-4]GlcNAc-R. Although 2-fucosyllactose Fuc1-2Gal1-4Glc) was retarded in elution from the columns, larger glycans containing the H-antigen Fuc1-2Gal1-3(4)GlcNAc-R interacted poorly with immobilized LTA. Our results demonstrate that immobilized LTA is effective in isolating glycans containing the Lex antigen and is useful in analyzing specific fucosylation of glycoconjugates. Abbreviations: LTA, Lotus tetragonolobus agglutinin; UEA-1, Ulex europaeus agglutinin-I; LNT, AAL, Aleuria aurantia agglutinin; Gal1-3GlcNAc1-3Gal1-3Glc; LNnT, Gal1-4GlcNAc1-3Gal1-3Glc; Lex, Lewis x antigen; Lea, Lewis a antigen; GDPFuc, guanosine 5-diphosphate--L-fucose  相似文献   

7.
Summary Optimal diets were determined for each of 109 individual Columbian ground squirrels (Spermophilus columbianus) at two sites in northwestern Montana. Body mass, daily activity time, and vegetation consumption rates for individuals were measured in the field, along with the average water content of vegetation at each ground squirrel colony. I also measured stomach and caecal capacity and turnover rate of plant food through the digestive tract for individuals in the laboratory to construct regressions of digestive capacity as a function of individual body mass. Finally, I obtained literature estimates of average daily energy requirements as a function of body mass and digestible energy content of vegetation. These data were used to construct a linear programming diet model for each individual. The model for each individual was used to predict the proportion of two food types (monocots and dicots) that maximized daily energy intake, given time and digestive constraints on foraging. Individuals were classified as optimal or deviating, depending on whether their observed diet was significantly different from their predicted optimal diet. I determined the consequences of selecting an optimal diet for energy intake and fitness. As expected, daily energy intake calculated for deviators (based on their observed diet proportion) was less than that for optimal foragers. Deviating foragers do not appear to compensate for their lower calculated energy intake through other factors such as body size or physiological efficiency of processing food. Growth rate, yearly survivorship, and litter size increase with calculated energy intake, and optimal foragers have six times the reproductive success of deviators by age three. Optimal foraging behavior, therefore, appears to confer a considerable fitness advantage.  相似文献   

8.
Contrary to other reports, we have found that the A type G6PD found in two permanent cell lines—HeLa (Gey), with its single cell clonal derivative HeLa S3, and Detroit 98, with its four clonal derivative lines—is not a single variant but rather at least three different isozymes. One is heat stable with normal specific activity and normal A type electrophoretic migration, another is heat labile with normal specific activity and normal A type electrophoretic migration, and the third is heat labile with reduced specific activity and slightly slow A type electrophoretic migration. We also found that in a mosaic cell population with respect to G6PD phenotype, the predominant G6PD phenotype varied randomly over a 5-month period, that the G6PD phenotype might be mutable in permanent cell lines, and that spontaneous human cell lines might not be HeLa cell contaminants as has been suggested.Aided by the National Institutes of Health General Research Support Grant # 5 S01 FR05507.  相似文献   

9.
Interleukin 2-dependent alloreactive cytotoxic T cell lines, with activity predominantly directed against the HLA-A2 antigen, have been generated in vitro by stimulating blood mononuclear cells from donors nonimmune to the Epstein-Barr (EB) virus with appropriate numbers of EB virus-transformed B cells from A2-homozygous individuals. Such effector cells were tested against a panel of EB virus-transformed target cell lines all expressing the serologically defined A2 antigen but typed into common A2 and variant A2 subgroups on the basis of their recognition by A2-restricted EB virus-specific cytotoxic T cells. Variant A2 responder cells cocultivated with common A2-bearing stimulators gave rise to effector T cell lines which recognized only the common A2-bearing subgroup of targets. By contrast, responder cells from A2-negative donors stimulated with common A2-bearing cells produced effector T cell lines in which the strong lysis of common A2-bearing targets was accompanied by a lower, but still significant, lysis directed against all targets within the variant A2 subgroup. In both cases, lysis of the target cells was blocked equally well by the anti-A2-specific monoclonal antibody MA2.1 as by the monoclonal antibody W6/32 specific for HLA-A, -B, and -C determinants. This suggests that HLA-A2 molecules possess at least two distinct sets of epitopes capable of inducing alloreactive T cell cytotoxicity: first, epitopes probably associated with T cell-restricting sites, which generate subgroup-specific responses, and second, epitopes shared by all A2 molecules, and perhaps associated with serologically defined sites, which generate pan A2 group-specific responses.Abbreviations used in this paper EB Epstein-Barr - IL-2 Interleukin 2 - UM unfractionated mononuclear - AET aminoethylisothiouroniumbromide hydrobromide  相似文献   

10.
The turning response to surface waves of clawed toads (Xenopus laevis) with an inactivated lateral line was reinvestigated to examine whether sensory systems other than the lateral line (second systems) are involved. Two methods were used to block the lateral line input: selective and reversible inactivation of the lateral line periphery using CoCl2 or chronic destruction with thermocautery. The time-course of the response recovery (response frequency, turning accuracy and reaction time) was recorded. Following CoCl2 inactivation 10 out of 13 animals did not respond to surface waves for at least 2 days. The remaining 3 animals gave sporadic turning responses. It is assumed that in these individuals a second system is permanently involved in the detection of surface waves parallel to the lateral line. Five days after the chronic destruction of the lateral line all animals again turned to the centre of surface waves. It is suggested that by this time the second system had become capable of substituting for the missing lateral line input. The response frequency and the accuracy of the turning response of lesioned animals varied considerably among individuals but was always lower than in untreated animals (tested up to 120 days).Abbreviation LED light emitting diode  相似文献   

11.
Zusammenfassung Pantothensäurebedürftige Hefezellen können ihren Bedarf an diesem Vitamin nicht allein aus -Alanin decken, sondern auch aus Benzoyl--Alanin, -Alanyl-d,l-Norleucin und -Alanyl-l-Histidin. Der Antagonist Asparagin hemmt die Verwertung dieser Peptide genauso wie diejenige der freien Aminosäure. Durch höhere Konzentrationen an -Alanin oder -Alanyl-d,l-Norleucin läßt sich die Hemmwirkung nicht allein kompensieren, es kommt sogar zu einer Förderung des Hefewachstums. Der Antagonist wird dann zum Synergisten.
Summary The -alanine containing peptides benzoyl--alanine, -alanyl-d,l-norleucine and -alanyl-l-histidine can substitute for the amino acid -alanine in a pantothenic acid requiring yeast. Asparagine, an antagonist of -alanine, affects these peptides in a similar manner. In combination with an overdose of -alanine or -alanyl-d,l-norleucine, asparagine is no longer an antagonist but becomes a synergist.
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12.
    
Zusammenfassung Die vor einem Jahr veröffentlichten Beobachtungen anTurnix sylvatica lepurana (Hoesch 1959) sind bis Ende 1959 durch Feststellungen an 3 gekäfigten Paaren und ihrem Nachwuchs wesentlich ergänzt worden. macht Kopulationsversuche besonders häufig nach Beginn der Eiablage und in den Brutpausen des , wirksame Begattungen scheinen aber nur dann zu gelingen, wenn das sein besteigt.Ein machte von Anfang März bis Ende November 1959 sieben Gelege, die vom bebrütet wurden. beginnt mit der Bebrütung des Geleges meist schon in der Nacht, die der Ablage des letzten Eies vorangeht, gleichviel, ob das Gelege aus 3, 4 oder mehr Eiern besteht. Vermutlich richtet es sich dabei nach dem Verhalten des , das am Tage vor dem letzten Ei dem Nest gänzlich fernbleibt, während es sich vordem tagsüber mehrmals aufs Nest gesetzt hatte.Es war nötig, das spätestens kurz vor dem Schlüpfen der Jungen zu entfernen, nicht nur, weil die Mutter das in der Brutzeit zu belästigen pflegt, sondern vor allem, weil sie frisch geschlüpfte Küken der eigenen Art durch Schnabelhiebe zu töten trachtet und sie zu diesem Zweck sogar unter dem Gefieder des hudernden Vaters hervorzuziehen sucht. Dieses Verhalten erlischt, wenn die Jungen etwa 20 Tage alt geworden sind.Sobald die Jungen dieses Alter erreicht haben, und nicht früher, beantwortet das die werbendenhu-hu-Rufe des , die bald nach Ablage des letzten Eies einsetzen, zum Zeichen seiner Bereitwilligkeit durch einen langgezogenen Ruftriii. Es gelang in einem Versuch, die Legepause des , deren Länge (im Mittel etwa 50 Tage) durch die Länge der väterlichen Brutpflege (Bebrütung, Aufzucht) erzwungen wird, durch Anbieten eines zweiten, noch unbeschäftigten wesentlich abzukürzen. In diesem Falle legte das das 1. Ei des neuen Geleges schon 11 Tage nach Ablage des letzten Eies seines vorherigen Geleges.Beide Geschlechter vermögen sich schon im Alter von 5 Monaten fortzupflanzen.
Summary The observations onTurnix sylvatica lepurana published a year ago (Hoesch 1959) have been considerably supplemented through further observations on three caged pairs and their offspring.The female makes attempts to copulate particularly frequently after she has started laying and during the period when the male is brooding but actual copulation appears to succeed only when the male mounts his mate.One female laid seven clutches from the beginning of March to the end of November 1959, all of which were brooded by the male.The male begins to sit usually during the night before the last egg of the clutch is laid, regardless of whether the clutch in question consists of 3, 4 or more eggs. It is probable that the male's reactions in this connection are dependent on the behaviour of the female, who remains away from the nest on the day before the last egg is laid, whereas on previous days she will often sit on the nest during the day.It proved necessary, at the latest just before the eggs hatched, to remove the female, not only because she bothers the male when he is brooding but also, and this is particularly important, because she endeavours to kill fresh hatched chicks of her own kind with blows from her beak and even, will try to pull them out from the covering plumage of the male. This behaviour on the part of the female disappears when the young are about 20 days old.As soon as the young have reached this age, but not before, the male answers the females courting hu-hu call, which begins soon after the laying of the last egg, with a long drawn-out triii which shows his readiness.In one experiment it proved possible, by introducing a second unpaired male, materially to shorten the pause between the laying of clutches by the female (usually around 50 days), which pause is normally regulated by the length of time the male requires to hatch the eggs and rear the young. In this experiment the female laid the first egg of the new clutch 11 days after laying the last egg of the previous clutch.Both sexes are able to reproduce at an age of 5 months.
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13.
Zusammenfassung An Laboratoriumszuchten vonReticulitermes lucifugus Rossi undReticulitermes flavipes Kollar (aus den Hamburger Befallsgebieten) werden Beobachtungen zur Biologie der Ersatzgeschlechtstiere mitgeteilt. Für die Durchführung dieser Beobachtungen wurden besondere Schaunester eingerichtet. Folgende Punkte der beobachteten Verhaltensweisen werden hier hervorgehoben: Die Nymphen der Ersatzgeschlechtstiere sammeln sich stets in Herden von 80–100 Einzeltieren und werden von einer Gruppe Arbeiter (als Hütehunde) bewacht. Die Arbeiter halten die Nymphen auf einem engen Raum zusammen und versuchen andere Nestgenossen von den Nymphen fernzuhalten. Alle ein bis zwei Tage wechseln die Herden ihren Standort. Das Weiterziehen geschieht gleichfalls in Form von Herden.Die Ernährung der Nymphen geschieht auf stomodealem Wege durch die Arbeiter. *** DIRECT SUPPORT *** A0180089 00007  相似文献   

14.
In Drosophila as in many organisms tubulins are encoded by a gene family. We have determined the complete nucleotide sequences coding for the 1 and 2 tubulins of Drosophila melanogaster and the 2 tubulin of D. hydei, and found these insect tubulins to be highly conserved and like tubulins of other organisms. This is discussed with reference to the possible functional domains of these proteins. — The 1 tubulin gene of Drosophila is constitutively expressed, whereas the 2 tubulin is expressed specifically in the testes. In D. melanogaster the amino acid sequences of these proteins are 95% homologous, differing at only 25 positions. In the testes the 2 tubulin participates in different microtubules as shown by genetic analysis (Kemphues et al. 1982). Interestingly, all of the amino acids characteristic of the testis-specific 2 tubulin are also present in the corresponding gene of D. hydei. Of special interest is the high degree of conservation of the carboxy-terminal domain in these functionally equivalent tubulins.  相似文献   

15.
Zusammenfassung Zur Klärung des Problems der Kastendetermination bei Formiciden konnte durch die Untersuchung der endomitotischen Polyploidisierung im Verlauf der Larvenentwicklung beigetragen werden. Endomitosen können hierbei nicht direkt beobachtet werden, die Polyploidisierung ist nur aus dem Wachstum der Kerne zu erschließen.Die Polyploidisierung sieben verschiedener Gewebe von Myrmica- wurde untersucht. Alle Tiere wachsen unter ständiger Polyploidisierung bis zum Puppenstadium heran. Während der Metamorphose werden alle hochpolyploiden Gewebe abgebaut. Besonders hohe Polyploidiegrade erreichen Gewebe der Stoffwechselorgane, wie Mitteldarm und Malpighische Gefäße. Oenocyten zeigen sehr unübersichtliche Verhältnisse. Die Spinndrüse wird im Zusammenhang mit dem Sekretionszyklus hochpolyploid. Fettzellen, Epidermis und Ganglien zeigen dagegen nur geringe Polyploidiegrade.Die Unterschiede in den verschiedenen Kasten werden festgestellt. Es zeigte sich, daß a anfänglich haploid sind and Geschlechtstiere einen Endomitoseschritt mehr ausführen als .Die Polyploidisierung entsprechender Gewebe von Lasius niger zeigt die gleiche Entwicklungstendenz. Futter- ud Temperatureinflüsse konnten festgestellt werden. Zwerg- zeigten Polyploidiegrade, die von denen der Normal- abweichen und dadurch auf blastogene Determination schließen lassen.-Brut gibt bei Ausschluß der Nestbegattung stets , die sick in ihren Kerngrößen nicht von den aus weiselrichtigen Nestern unterscheiden.Alle untersuchten Formicidenarten weisen die gleiche Entwicklungstendenz auf.Beobachtungen über Entwicklungsdauer, Eiablage und -Brut-Entwicklung werden angefügt.Auf Grund der Ergebnisse wurde zu Fragen der endomitotischen Polyploidisierung Stellung genommen. Die Gründe, die zur Annahme eines Polyploidisierungsvorganges in der Larvenentwicklung der Formiciden führen, werden diskutiert. Polyploidie wird in Beziehung gesetzt zur Körpergröße der Tiere, zur phylogenetischen Entwicklungshöhe und zur Gewebsfunktion (Deutung als Sparsamkeitsmaßnahme). Hypothesen zur Kastendetermination werden durch die Ergebnisse unterstützt.  相似文献   

16.
Summary The occurrence of the AT chain (i.e. A75 Ile Thr) in different populations was evaluated through a study of 4250 cord blood samples and blood samples from more than 350 SS1 patients. High frequencies were observed in Italy, Yugoslavia, Turkey, Holland, but also in Japan, Vietnam, and India. The chain is (nearly) absent in the Black population of Ghana and Kenya, and low frequencies were observed in China and Australian aborigines. Only a few adult SS patients (18 out of 357) were AT heterozygotes. The chromosomes with the AT globin gene were mapped through an evaluation of the presence of 10 different restriction sites. The AT chromosomes from different populations were closely related and had the same subhaplotypes of [--++-+] (Hinc II 5 to ; Xmn I 5 to G; Hind III in G and A; Hinc II in and 3 to ), quite different from the subhaplotypes seen for AT negative chromosomes.2 This suggests a common ancestor which may have originated in Southern Europe. An evaluation of the chain production by both chromosomes in SS patients and -thalassemia heterozygotes was possible for subjects with an AT heterozygosity. It was concluded that in -thalassemia trait, the chain synthesis is directed for about two-thirds by the thalassemic chromosome and for about onethird by the normal chromosome; the contribution by the normal chromosome decreases with a decrease in total chain production.This is contribution #0890 of the Department of Cell and Molecular Biology, Medical College of Georgia, Augusta, GA 30912, USA  相似文献   

17.
Zusammenfassung In den Jahren 1961 und 1962 wurden Untersuchungen mit Hilfe der Exosmose-Methode durchgeführt, um sich über die Frostresistenz von nahezu 100 Apfelsorten zu orientieren. Die Versuchsergebnisse (ausgedrückt in RLF-Werten, d. h. als Proportion des elektrolytischen Widerstandes zwischen den Kontrollen und den kältebehandelten Pflanzenteilen) zeigen gute Übereinstimmung mit den Resultaten anderer Härtebeurteilungsmethoden, z. B. mit den Gefrierversuchen in Gefrierkammern und mit den amerikanischen, deutschen und schweidischen Freilandbeobachtungen. Die berechneten Korrelationskoeffizienten gaben Werte von r=>+0,750 mit einer statistischen Sicherheit von P=<0,001. Es gibt jedoch Sorten, welche sich unter den verschiedenen Versuchsbedingungen nicht gleichartig verhielten. In diese Gruppe gehören die Sorten Goldparmäne, James Grieve, Lanes Prince Albert, Schöner aus Nordhausen, Slava Petersburga und Transparente de Croncels. Der Zusammenhang zwischen der geographischen Herkunft und der Frostresistenz ist augenfällig. Die durchschnittlichen RLF-Werte der frostempfindlichen oder sehr frostempfindlichen französischen Sorten liegen bei ungefähr 150, die der finnischen und baltischen frostharten Sorten dagegen unter 110. Die Rangordnung der verschiedenen Klimagebiete erfolgte entsprechend der geographischen Lage. Es gab Sorten, die der allgemeinen Tendenz nicht folgten und sich abweichend verhielten. Hierzu gehören: Transparente de Croncels, (Frankreich), Wealthy (USA), Cox Pomona und Ribston (Großbritannien). Über eine wesentlich schlechtere Resistenz, als auf Grund des Ursprungsgebietes zu erwarten war, verfügt Ontario (Kanada).  相似文献   

18.
Molecules of deoxyribonucleic acid and synthetic polydeoxyribonucleotides (NA) in the particles of liquid-crystalline dispersions resulting from interaction with chitosan are accessible to interaction with intercalators. The intercalation is accompanied by alteration in the direction of spatial twist of cholesterics of NA–chitosan complexes. This effect is absent in the case of classical cholesterics produced from NA molecules via phase exclusion, i.e., the cholesteric structure of NA–chitosan complex is very labile as distinct from classical cholesteric NA.  相似文献   

19.
The paper aims to represent and scale biometeorological sensations through a thermal index which comprises the effects of temperature, humidity and wind. The cooling power of a measured combination of wind speed and air temperature is equated with that due to the combination of a reference wind speed (related to the air movement experienced by a person walking in still air), and a derived aerodynamic temperature. A biometeorological temperature which is the average of such an aerodynamic temperature and a conventionally measured wet bulb temperature is shown to afford a better measure of comfort in Spain than some other, alternative indices.  相似文献   

20.
Rapid multiplication of axillary meristems and direct shoot development occurred from nodal explants of mature Eucalyptus tereticornis Sm. with 5.3 M NAA, 1.1 M IAA and 4.4 M BA in Murashige-Skoog medium. Repeated subcultures of the second generation shoot cultures into low cytokinin-auxin containing media (0.44–0.88 M BA+0.1 M NAA) yielded axillary microshoots in large numbers. Half-strength MS liquid medium with 4.9 M IBA, 5.5 M IAA and 5.3 M NAA for four days, half-strength semi-solid hormonefree MS medium with charcoal, and MS liquid medium without charcoal and hormones, in sequence, induced rooting of shoots in the dark. This system is suitable for the mass propagation of this difficult-to-root eucalypt.Abbreviations BA 6-benzyladenine - IAA indole-3-acetic acid - IBA -indole-3-butyric acid - 2-iP isopentyl adenine - Kn kinetin - MS Murashige-Skoog - NAA -naphthalene acetic acid - PVP polyvinylpyrrolidone  相似文献   

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