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1.
Zusammenfassung Während der Meiose von Coprinus werden bipolare Centriolen-ähnliche Strukturen sichtbar, an denen die Mikrotubuli des spindelapparates entstehen.
The development of the spindle during meiosis of Coprinus radiatus
Summary During the meiosis of Coprinus bipolar centriol like structures are to be seen. They seem to organize the microtubuli of the spindle-apparatus.
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2.
The MediterraneanOrobanche variegata has n = 38. This is the third tetraploid taxon known from sect.Orobanche.
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3.
Zusammenfassung Beim Abbau von Tetradecanol durch Pseudomonas aeruginosa wird Tetradecanal als Semicarbazon angereichert und als 2,4-Dinitrophenylhydrazon nachgewiesen.Die Gewinnung eines Aldehyds wird durch Anreicherung aus einer wachsenden Kultur möglich.
Accumulation of aldehyd intermediate by Pseudomonas aeruginosa in growing culture on tetradecanol
Summary In the oxidation of tetradecanol by Pseudomonas aeruginosa tetradecanal was accumulated as semicarbazon and was identified as 2,4-Dinitrophenylhydrazon.This confirms the possibility of production of an intermediate aldehyde out of the growing culture.
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4.
Theligonum cynocrambe and 13 species ofRubiaceae contain S-type sieve-element plastids, wide-spread in Dicotyledons. Alignment ofTheligonum toCaryophyllales (Centrospermae), especiallyPhytolaccaceae, is unlikely, because this order is characterized by specific P-type plastids. SEM investigations show the pollen exine ofTheligonum to be microreticulate, with additional supratectate spinules.Asperula and other genera of the tribeRubieae have a tectum perforatum (punctitegillate sexine), also with supratectate verrucae or spinulae.—Thus ultrastructure suggests (but not definitely proves) relationships betweenTheligonum andRubiaceae, while affinities betweenTheligonum andCaryophyllales are excluded.
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5.
Zusammenfassung Die Haarhyphen des Peritheciums von Chaetomium globosum besitzen eine charakteristische Wandstrukturierung durch kraterförmige Aufwölbungen der äußeren Wandschicht. Diese Strukturen können taxonomisch von Interesse sein.
Wall structures of terminal hairs in the perithecium of Chaetomium globosum
Summary The terminal hairs of perithecia in Chaetomium globosum exhibit special wall configurations due to local vaulting of the outer wall layer. The structures might be of significance in species identification.
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6.
Günther Werz 《Planta》1966,69(1):53-57
Zusammenfassung Morphologisch erkennbare Primärvorgänge bei der REalisation der morphogenetischen Prozesse Wirtel- und Hutbildung bei Acetabularia-Zellen werden beschrieben.Wir fanden, daß die Prozesse, welche die Ausprägung einer spezifischen Zelldifferenzierung bestimmen, durch charakteristische Lyseprozesse in der bereits vorhandenen Zellwand eingeleitet werden. Diese werden ihrerseits wieder durch zeitlich früher erfolgende Prozesse induziert.
Primary processes in the realization of morphogenesis in Acetabularia
Summary Primary processes in the realization of morphogenesis during whorl and cap differentiation in Acetabularia cells are described.It has been demonstrated that the morphological appearance of these specific cellular differentiations is initiated by characteristic lytic processes within the already existant cell wall. It is proposed that they are induced by specific cytoplasmic processes.
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7.
Zusammenfassung Der sterile Kannensaft von drei Nepenthes-Arten wurde chromatographisch und elektrophoretisch untersucht. Bei Auftrennungen durch Adsorptionschromatographie an Ecteola-Cellulose und durch Elektrophorese wurde jeweils nur eine proteolytische Enzymfraktion erhalten. In gereinigten, kohlenhydratfreien Enzymfraktionen wurde ein pH-Optimum bei 2,2 und ein Temperaturoptimum bei 50°C gefunden.
Purification of the proteinase from Nepenthes pitcher secretion
Summary The proteolytic enzymes from the sterile secretion of the pitchers of 3 Nepenthes species were purified to electrophoretic homogenity by chromatography on Ecteola cellulose. The properties of the purified enzymes were investigated.
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8.
If exsiccated trichomes ofPseudanabaena galeata are immersed in water, striking changes occur as a consequence of lysis and maceration. The locomotion of living trichomes differs from that inOscillatoriaceae. This and other differences make it doubtful, whetherPs. galeata belongs to theOscillatoriaceae; at any rate it occupies an aberrant position.
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9.
Varicellaria carneonivea is lichenized withAsterochloris phycobiontica, a new member of theChlorococcales. In the free-living state this species reproduces by zoo- and aplanospores; autospores are lacking. Sporangia develop an internal local thickening of the wall, which marks the later aperture. A group of dictyosomes apparently contributes to the formation of this thickening. Secondary carotenoids dissolved in droplets or irregular masses of oil are deposited around and within the pyrenoid.
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10.
Zusammenfassung Die sechs auf den Samoa-Inseln lebenden Taubenarten bewohnen alle denselben Lebensraum (tropischer Urwald), wo sie mit akustischen Signalen inter- und intraspezifisch kommunizieren. Bei den sechs typischen Standortrufen handelt es sich mit Ausnahme vonDucula pacifica um wenig strukturierte u-Rufe, die auf zweierlei Weise modifiziert werden. Von drei Arten wird ein kurzer Ruf in Reihen wiederholt mit Unterschieden von Ruflänge und Intervallen. Zwei Arten bilden ihren Standortruf aus unterschiedlich langen u-Komponenten, die mit wechselnder Betonung vorgetragen werden. Der gurrende Standortruf vonDucula pacifica kann als zeitliche Auflösung eines u-Rufes angesehen werden. Die Abwandlung dieses Rufes gewährleitet die Arterkennung und Artabgrenzung.
Acoustic features of the six species of pigeons of the Samoan Islands
Summary The six species (Didunculus strigirostris, Columba vitiensis, Gallicolumba stairi, Ptilinopus porphyraceus, Ptilinopus perousii, Ducula pacifica) all occur in the same habitat of tropical rain forest, where they communicate inter- and intraspecifically by acoustic signals. With the exception ofDucula pacifica, these advertising coos are relatively unstructured oo-calls, being modified in two different ways. Three species repeat a short call in series, with varying length and intervals in the different species. In two species the advertising coos consist of oo-components with different length, being sung with varying intonation. The cooing call ofDucula pacifica can be interpreted as a temporal resolution of one oo-call. By using a relatively unstructured oo-call, the pigeons benefit from not being localized easily by predators. The modification of this call guarantees in principle the protection of the species as well as their recognition and differentiation.
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11.
In theChrysophyceae as well as in different species ofCryptomonas bilobed chromatophores are present. These chromatophores consist of two large parietal lobes closed to the lateral sides of the cell and joined by a narrow bridge on its dorsal part. A survey of all species with a single bilobed chromatophore is given. Besides, also species with two separate chromatophores have been found. The presence of several chromatophores inCryptomonas cells is doubtful. The morphology of the chromatophores has to be taken into consideration in the taxonomy ofCryptomonas.
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12.
Systematics and distribution pattern of the free living nematodes in the benthos of Neusiedlersee outside the reed belt are described. 26 species have been found some of which demonstrate a distinct horizontal distribution pattern, correlated with the wind influence on benthic conditions in the lake. Detailed systematic account is given of the species found, especially the genera Udonchus Cobb and Monhystrella Cobb, as well as of the following species: Plectus andrassy Timm 1971, Paraphanolaimus microstomus (Daday, 1905), Monhystera spp., Theristus flevensis Schuurmans-Stekhoven, 1935, Tripyla glomerans Bastian 1865, Tobrilus gracilis (Bastian, 1865) and Amphidelus lemani longicaudatus n. ssp.
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13.
Zusammenfassung Die Untersuchung der Bürzeldrüsensekrete von Dampfschiffenten (Tachyeres pteneres, T. patachonicus) zeigt, daß es sich um Esterwachse handelt, deren Komposition typisch fürAnseriformes-Arten ist. Eine Strukturanalyse der Wachsbestandteile weist auf eine nahe Verwandtschaft vonTachyeres mitSomateria undAnas und auf eine weitere systematische Entfernung vonTadorna hin. BeideTachyeres-Arten sind chemotaxonomisch unterscheidbar, was ihnen den Rang unterschiedlicher Arten zuerkennt, da Rassen nach dieser Methode nicht diskriminierbar sind.
The systematic position of steamer ducks(Tachyeres) within the order Anseriformes
Summary The uropygial gland secretions from steamer ducks (Tachyeres) are ester waxes the composition of which are typical for Anseriformes species. A chemical analysis of the wax constituents indicates a close relationship betweenTachyeres andSomateria andAnas as well.Tadorna seems to be more distant from these subfamilies. BothTachyeres species are chemotaxonomically discernible which leads to the conclusion that they actually are different species not races.
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14.
Zusammenfassung Die bemerkenswerte Sternbildung von Agrobacterium luteum Stamm A61 (Moll et al., 1967; Ahrens, 1968) ist auf polare Fimbrien zurückzuführen, die um die Sternaggregate ausgebreitet sind. Es wird angenommen, daß sich Schwärmzellen an den Fimbrien verfangen und durch Kontraktion rasch zum Stern gezogen werden. Nach elektronenoptischen Präparaten sind die Fimbrien bis zu 10,5 lang und können die beobachtete Sternbildung gut erklären. Agrobacterium luteum Stamm B14 besitzt ebenfalls lange polare Fimbrien. Beide Stämme tragen peritriche Geißeln, deren Struktur sich deutlich von den dünnen und unregelmäßigen Fimbrien unterscheidet.
The function of fimbriae in the peculiar star formation of Agrobacterium luteum
Summary The remarkable way of star formation in Agrobacterium luteum strain A61 (Moll et al., 1967; Ahrens, 1968) was found to be due to polar fimbriae which are spread around the star-shaped aggregates. It is assumed that swarmers adhere to the fimbriae and, by contraction, are swiftly pulled towards the star. As seen in electron microscopic preparations, the fimbriae are up to 10,5 long and may well explain the star formation observed. Agrobacterium luteum strain B 14 also possesses long polar fimbriae. Both strains have peritrichous flagella, the structure of which being clearly distinct from the delicate and irregular fimbriae.
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15.
The frutescent species of the lichen genusCaloplaca are usually united in sect.Thamnoma, but they do not form a natural group. They are derived from different species groups within sect.Gasparrinia from different parts of the world, presumable from species having scleroplectenchymes in cortex and medulla. The algal cells are concentrated between the scleroplectenchymatic strands in large and dense groups, from where medullary plectenchyme extends to the cortex and forms characteristic pseudocyphellae there.—Most of the species seem to be ornithocoprophilous; they grow on rocks along marine coasts where much fog is induced by cold currents.—Caloplaca cribrosa is endemic in Tasmania and New Zealand,C. regalis and the doubtfulC. ambitiosa belong to the antarctic element.C. fragillima from central Chile seems to be propagated by thallus fragments.C. coralloides andC. thamnodes are endemic to California and Baja California respectively.C. cladodes from the Rocky Mountains deviates in many characteristics from the other species i.a. by it different ontogenetic development, reduced spore septum, and cementing amyloid polysaccharides within the scleroplectenchymatic strands. The African species are characterized by their distinctly dorsiventral lobes and usually possess oil cells in some of the paraphyses.Caloplaca bonae-spei, C. fragillima andC. thamnodes are new to science.
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16.
Zusammenfassung Die Fischfamilie der Cypriniden zeigt nach Chromosomenzahl und DNS-Gehalt/Zelle ein Diploid-Tetraploid-Verhältnis. Eine Duplikation der MDH-Isoenzyme läßt sich in der tetraploiden Gruppe nachweisen. Nur der tetraploide Cyprinus carpio hat ein Muster entsprechend der diploiden Gruppe.
Polyploidization in the fish family Cyprinidae Duplication of the gene loci for NAD-dependent malate dehydrogenase
Summary The fish family Cyprinidae can be classified into two groups, a diploid one and a tetraploid one, as shown by chromosome analysis and measurements of the DNA content per cell. Duplications of the MDH isoenzymes can be demonstrated in the tetraploid group with one exception: Cyprinus carpio reveals the diploid pattern.


Direktor: Prof. Dr. Dr. H. Ritter

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.  相似文献   

17.
Population analyses, scatter diagrams and field observations demonstrate thatOphrys helenae is morphologically (and ecologically) well separated from the partly sympatricO. mammosa andO. ferrumequinum in N. Greece. Hybrids with the distantly relatedO. mammosa are very rare.
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18.
The following new hybrids are described:Euphrasia ×dilata = E. hirtella Jordan exReuter ×alpina Lam.;Euphrasia ×trikoviana = E. tricuspidata L. ×rostkoviana Hayne. The chromosome number ofEuphrasia tricuspidata L. has been established for the first time: 2n = 22.
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19.
Summary Haustoria ofCuscuta odorata R. & P. andC. grandiflora H.B.K. show continuous traces of sieve elements, connecting the phloem of the host with that of theCuscuta shoot. The continuity of this haustorial phloem is discernible by callose fluorescence after staining with aniline blue. The fine structural criteria for sieve tubes are analyzed electronmicroscopically, with special respect to sieve pores, P-protein, and a distinct wall-standing smooth surfaced ER. Within the central part of the haustorium sieve tubes are elongated, while the elements abutting the phloem of theCuscuta shoot are nearly isodiametric in shape. Both elements are associated with rather large companion cells, derived from an unequal division.
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20.
Zusammenfassung An 17 Stämmen der Gattung Pediococcus, die auf Grund charakteristischer physiologisch-biochemischer Merkmale aus einer Anzahl von etwa 500 Kulturen unterschiedlicher Herkunft ausgewählt wurden, werden mit Hilfe der DNS/DNS-Hybridisierung die verwandtschaftlichen Beziehungen untersucht. Dabei wird die Eigenständigeit der Arten P. pentosaceus, P. acidilactici, P. parvulus, P. damnosus und P. halophilus bestätigt. Der für P. acidilactici vorgeschlagene Neotyp-Stamm NCDO 1859 ist jedoch nach den vorliegenden Ergebnissen ein echter P. pentosaceus. Ein Stamm von P. dextrinicus, der früher bereits als P. cerevisiae var. dextrinicus beschrieben wurde, zeigt zu keiner untersuchten Art eine genetische Verwandtschaft auf der Basis der DNS/DNS-Homologie. Zwei aus Bier und Bierhefe isolierte Stämme, die hinsichtlich des Phänotyps P. parvulus nahestehen, zeigen weder zu dieser Art noch zu allen anderen bisher beschriebenen Arten hinsichtlich des Genotyps einen hohen Verwandtschaftsgrad.
DNA-DNA homology studies on the genus Pediococcus
17 strains of Pediococcus, including new isolates and strains from various collections, were investigated by nucleic acid hybridisation. Most of the newly isolated strains, selected from about 500 strains according to physiological and biochemical characters, could be attributed to known species. The reassociation data demonstrate the separate status of P. pentosaceus, P. acidilactici, P. damnosus, P. parvulus and P. halophilus. The proposed neotype strain of P. acidilactici NCDO 1859, however, has been found to be in reality a genuine P. pentosaceus. P. dextrinicus, formerly described as P. cerevisiae var. dextrinicus showed a remarkable lack of relationship to any of the strains tested. Two isolates exhibiting a high phenotypic similarity to P. parvulus show little genetic relationship to this and especially to all other species.

Abkürzungen CTAB N-cetyl-N,N,N-trimethyammoniumbromid - EDTA Äthylendiamintetraessigsäure - PPO 2,5-Diphenyloxazol - POPOP 1,4-Bis-(5-phenyl-2-oxazolyl)-benzol - SSC Saline-Trinatriumcitrat (0,15M NaCl, 0,015M Trinatriumcitrat, pH 7,0) - Tris Tris(hydroxymethyl)-aminomethan - T m mittlere Schmelztemperatur der DNS Adresse für Sonderdruck-Anforderungen  相似文献   

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