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  • 1
    ISSN: 1570-7458
    Keywords: host suitability ; acceptance ; biological control ; new associations ; Lepidoptera ; Pyralidae ; New World ; Old World ; stemborers ; Braconidae ; larval parasitoids ; Gramineae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The present study examined the acceptability and suitability of Old World stemborers (Chilo partellus and C. orichalcociliellus) for the development of New World parasitoids (Apanteles deplanatus and A. minator) and New World stemborers (Diatraea saccharalis and D. grandiosella) for the development of Old World parasitoids (Cotesia sesamiae, C. flavipes and C. chilonis). Results revealed that acceptance and suitability were high in old associations. In new associations, parasitoids accepted about 60% of the new association hosts. In addition, 10 out of 17 new associations were successful. Apanteles species appeared to be more physiologically host specific than Cotesia species. For example, two of four new association hosts were accepted by A. deplanatus and only one (D. saccharalis) was partially suitable for progeny development. Among the Cotesia species, Cotesia flavipes appeared to have a wider host range than the two other species. It attacked all hosts offered and successfully parasitized all but one (D. grandiosella). Diatraea saccharalis was accepted and was a suitable host for the development of all parasitoid species tested, whereas D. grandiosella was unsuitable for the development of four out of five parasitoid species tested. No clear pattern was observed as behavioral acceptance did not always agree with the pattern of physiological suitability. Implications of these findings for importation biological control of stemborers are discussed.
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  • 2
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    Entomologia experimentalis et applicata 78 (1996), S. 341-348 
    ISSN: 1570-7458
    Keywords: probing behaviour ; electrical penetration graph ; EPG ; hydroxamic acids ; DIMBOA ; DIBOA ; cereal aphids ; Diuraphis noxia ; Russian wheat aphid ; cereals ; Gramineae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The feeding behaviour of Diuraphis noxia (Kurdjumov) (Homoptera: Aphididae) was electronically monitored on five cereal species (Triticum aestivum L., T. turgidum L., Secale cereale L. and x Triticosecale Wittmack) containing different hydroxamic acids levels and on Hordeum vulgare L., lacking these compounds, by means of a DC-System. With increasing DIMBOA (2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one) levels D. noxia showed less probing particularly before reaching the phloem phase and a lower percentage of aphids achieved sustained phloem ingestion. However, no significant correlation was found between DIMBOA levels and the total time of phloem feeding. These findings indicate that factors from the mesophyll and vascular tissues appear to be involved in the effects of resistance. The underlying mechanism, however, remains unclear. Thus, DIMBOA seems to be only part of the chemical defenses of the cereal plants that might be implicated in D. noxia resistance.
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  • 3
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    Cellular and molecular life sciences 47 (1991), S. 599-602 
    ISSN: 1420-9071
    Keywords: Sorghum vulgare ; Gramineae ; oxalate oxidation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The presence of an oxalate oxidase (EC 1.2.3.4) has been demonstrated in 15,000×g supernatants prepared from 10-day-old seedlings of three genotypes ofSorghum vulgare: grain sorghum hybrid (CSH-5), grain-cum-forage sorghum (PC-6) and forage sorghum (PC-1). The specific activity of the enzyme in the different tissues of seedlings was found to be present in the order leaves 〉 stems 〉 roots in PC-6 and PC-1, but this order was reversed in CSH-5. A comparison of the different properties of the leaf enzyme of these three genotypes of sorghum revealed that the enzyme has maximum activity in the acidic pH range from 4.0 to 5.0 and in the temperature range from 37°C to 40°C. The enzyme was stimulated by Cu2+ and Fe2+. The rate of H2O2 formation in the enzyme reaction was linear up to 5 min and was stoichiometrically related to oxalate consumption. The enzyme is unaffected by Na+ at physiological concentration (0.15 M). The superiority of this enzyme over moss and other plant enzymes for enzymic determination of urinary oxalate is discussed.
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  • 4
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    Entomologia experimentalis et applicata 40 (1986), S. 259-262 
    ISSN: 1570-7458
    Keywords: Gramineae ; barley ; Hordeum ; Aphid ; Rhopalosiphum padi ; Schizaphis graminum ; greenbug ; alkaloid ; gramine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé La teneur de gramine (N,N-dimethyl-3-aminomethyl-indole) dans différentes cultures de seigle présente des variations comprises entre 0 et 2,8 mmoles/Kg (poids frois). Les varietés dépourvues de gramine sont plus sensibles à l'attaque des pucerons. Le taux de croissance de la population des Rhopalosiphum padi a une correlation négative avec la teneur en gramine des feuilles de plantules de seigle. D'ailleurs, la gramine diminue les taux de nourrissement, de survie et de réproduction des pucerons alimentés avec des diètes artificielles contenant des concentrations du produit testé, similaire à celles trouvées pour les feuilles des plantes. Donc, on suggèrent que la gramine peut être un des facteurs responsables de la résistance des plantules de seigle contre l'attaque de Rhopalosiphum padi.
    Notes: Abstract Gramine (N,N-Dimethyl-3-aminomethylindole) content in various barley cultivars varied from 0 to 2.6 mmoles/kg fresh weight. Those cultivars which were lacking gramine were the most susceptible to the aphid Rhopalosiphum padi (L.). The population growth rate of R. padi negatively correlated with gramine content in leaves of barley seedlings. In addition, gramine incorporated in artificial diets decreased survival, amount of diet ingested and reproduction of aphids at concentrations similar to those found in plant leaves. Thus, it is suggested that gramine may be one of the factors responsible for the resistance of barley seedlings to R. padi.
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  • 5
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    Entomologia experimentalis et applicata 41 (1986), S. 3-10 
    ISSN: 1570-7458
    Keywords: Acremonium loliae ; endophyte ; Sphenophorus parvulus ; Curculionidae ; Lolium perenne ; Gramineae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé Des études récentes ont montré que la présence d'A. loliae à l'intérieur de L. perenne augmentait sa résistance à plusieurs insectes, dont Listronotus (Hyperodes) bonariensis et quelques pyralesnous signalons ici que le même endophyte améliore aussi la résistance à Sphenophorus parvulus (Curculionidae). Des dégâts de S. parvulus ont été observés sur gazon en 1981, 1983 et 1984. Des différences marquées quant à la réaction des cultivars ont été notées; des études ultérieures ont montré que la résistance des cultivars était associée à des niveaux très élevés d'endophytes, ceux-ci étant rares ou absents des cultivars sensibles. La transmission maternelle de la résistance à S. parvulus améliorée par la présence de l'endophyte qui avait été mise en évidence peut s'expliquer par le pourcentage élevé de graines transmettant le champignon. Les cultivars ‘Pennant’, ‘Premier’, ‘Regal’ aux niveaux élevés d'endophytes présentent peu de dégâts en gazon. Les avantages dûs à la présence de l'endophyte, exprimés par une meilleure résistance aux insectes, étaient particulièrement spectaculaires lorsque l'entretien de gazon était sommaire. L'amélioration due à l'endophyte n'apparaissait pas avec les gazons bien entretenus où il n'y avait pas de dégâts d'insectes. Ceci ne réduit en rien l'intérêt de cette forme de résistance aux insectes. Des questions importantes restent à résoudre: action de l'endophyte sur l'hôte, identification et influence des toxines éventuellement impliquées, examen d'autres plantes et insectes concernés.
    Notes: Abstract Enhanced resistance in perennial ryegrass, Lolium perenne L., to the bluegrass billbug, Sphenophorus parvulus Gyllenhal is associated with the presence of a fungal endophyte, Acremonium loliae Latch et al. Severe billbug infestations occurred in 1981, 1983, and 1984 in two different turf evaluation field trials. Striking differences in cultivar response were observed. Subsequent investigations led to the discovery that billbugresistant ryegrass entries had very high levels of endophyte infection; whereas, susceptible entries had little or no endophyte infection. Further, the resistance was found to be maternally transmitted, and its dramatic prevalence within a maternal line was explained by the high frequency (over 95%) of seed transmission of the endophyte. This newly recognized source of plant resistance to several insect pests warrants additional study.
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  • 6
    ISSN: 1570-7458
    Keywords: Acremonium loliae ; Gramineae ; Lolium perenne ; Noctuidae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé Le ray-grass vivace (Lolium perenne), contaminé par le champignon endophyte Acremonium loliae Latch, Christensen & Samuels, a présenté une augmentation de la resistance à de nombreux coléoptères et lépidoptères nuisibles. Cette note examine les réactions de Spodoptera eridania Cramer (Lépido., Noctuidae) alimenté sur trois lignées de ray-grass contaminées par le champignon et trois lignées ‘saines’. Après 168 h d'alimentation sur ray-grass contaminé, les chenilles presentent une très forte mortalité; la survie n'est que de 7 à 13% contre 82 à 90% pour le ray-grass sain. Le décès brutal des chenilles correspond à leur alimentation sur la base de la plante ou la concentration du champignon est la plus forte. Les chenilles consomment constamment, broutant plus des 2/3 du feuillage du ray-grass; les broutements des six séries ne différaient pas significativement. Au bout de 24 h, la nombre de chenilles passées du 3ème au 4ème stade, et l'augmentation de poids sont plus élevés pour les séries sur plante contaminée, ce qui suggère un avantage initial pour les chenilles en présence de champignon endophyte, l'analyse en poids sec a montré que l'augmentation de poids initial est réel. Entre 48 et 144 h, cependant, le nombre de 4ème stade et le poids des chenilles sont les mêmes dans les deux séries. Après 144 h, le poids des chenilles sur ray-grass contaminé diminue significativement; aucune n'était parvenue au 5ème stade, contre 11% sur ray-grass ‘sain’. Nous n'avons pas observé de signes apparents de neurotoxicité. Au lieu de cela, il ya a eu interaction avec un processus physiologique fondamental, ce qui a provoqué une forte perte de poids larvaire et la mort, indiquant l'intervention d'inhibiteurs métaboliques.
    Notes: Abstract Larvae of the Southern armyworm Spodoptera eridania Cramer (Lepidoptera:Noctuidae), feeding on perennial ryegrasses (Lolium perenne L.) infected with an endophytic fungus (Acremonium loliae Latch, Christensen and Samuels), had a much lower survival rate (7–13%) than larvae feeding on endophyte-free ryegrasses (82–90%). Death of the larvae on endophyte-infected entries occurred rapidly between 144 h and 168 h of feeding. This corresponded with armyworms feeding on the base of the plant, where endophyte concentration is highest. Twenty-four hours after the start of the bioassay the larval mass and rate of larval development were significantly higher on endophytic entries. From 48–144 h no differences were seen, but after 144 h the mass of larvae on endophyte-infected grasses sharply declined. Observations from this bioassay further substantiate the association between A. loliae-infected ryegrass and antibiosis to several lepidopterous and coleopterous insect pests.
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  • 7
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    Calcified tissue international 10 (1972), S. 82-90 
    ISSN: 1432-0827
    Keywords: Calcium ; Phosphate ; Precipitation ; Kinetics ; Chemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La cinétique de la formation et de la transformation des précipités de phosphate de calcium, obtenus en mélangeant de volumes égaux de solutions à 6×10−3 M de calcium total et/ou phosphate total est étudiée à 25°C. Les solutions de phosphate sont préajustées à un pH de 7.4. Les changements de pH et de turbidité des solutions sont suivis simultanément en fonction du temps. Les précipités sont isolés à des intervalles de temps variables et caractérisés par diverses méthodes physico-chimiques. Initialement un précipité avec un rapport molaire Ca/P de 1.5, amorphe aux rayons X et en diffraction électronique, est formé. Le spectre IR indique la présence de PO 4 3− et de HPO 4 2− . Après une période métastable, on observe la précipitation d'un matériel cristallin dans ou sur la phase amorphe. Vingt quatre heures après préparation de l'échantillon les précipités présentent surtout les caractères du phosphate octocalcique.
    Abstract: Zusammenfassung Die Kinetik der Bildung und Transformation von Calciumphosphat-Niederschlägen wurde bei 25°C untersucht. Es wurden dazu gleiche Volumen von Lösungen gemischt, bei einer Konzentration von 6×10−3M totales Calcium und/oder totales Phosphat. Die Phosphatlösungen wurden zuerst auf pH 7,4 eingestellt. Veränderungen des pH und Trübung der Lösungen wurden gleichzeitig als eine Funktion der Zeit aufgezeichnet. Niederschläge wurden in verschiedenen Zeitintervallen isoliert und mit verschiedenen physiko-chemischen Methoden charakterisiert. Am Anfang wurde ein Niederschlag mit einem molaren Ca/P-Verhältnis von 1,5, im Röntgenbild und in der Elektronendiffraktion amorph, gebildet. Infrarotspektren deuteten die Anwesenheit von PO 4 3− - und HPO 4 2− -Ionen an. Nach einer metastabilen Periode erfolgte ein Niederschlag aus kristallinem Material innerhalb oder auf der amorphen Substanz. 24 Std nach der Herstellung der Proben zeigten die Niederschläge in der Hauptsache die Charakteristiken von Octocalciumphosphat.
    Notes: Abstract The kinetics of the formation and transformation of calcium phosphate precipitates obtained by mixing equal volumes of solutions, 6×10−3 M in total calcium and/or total phosphate was investigated at 25°. The phosphate solutions were preadjusted to pH 7.4. Changes of the pH and turbidity of the solutions were followed simultaneously as a function of time. Precipitates were isolated at various time intervals and characterized by different physicochemical methods. Initially a precipitate with a molar Ca/P ratio of 1.5, amorphous to X-ray and electron diffraction was formed. IR spectra indicated the presence of PO 4 3− and HPO 4 2− ions. After a period of metastability, precipitation of a crystalline material within or upon the amorphous matter occurred. Twenty four hours after sample preparation the precipitates showed mainly the characteristics of octacalcium phosphate.
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  • 8
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    Calcified tissue international 16 (1974), S. 145-152 
    ISSN: 1432-0827
    Keywords: EHDP ; Bone ; Chemistry ; Serum ; Rabbits
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract The effects of disodium ethane-1-hydroxy-1,1-diphosphonate (EHDP) on bone and serum chemistry were investigated in adult rabbits. EHDP was administered by subcutaneous injection at doses of 0.25, 2.5 and 10 mg/kg body weight/day for of 28 days. Blood samples were obtained weekly from each rabbit and serum levels of total calcium, ionized calcium, inorganic phosphate and alkaline phosphatase were determined. At the end of the treatment period all rabbits were sacrificed and the tibiae removed for chemical analysis and histological evaluation. The effect of EHDP administration on serum chemistry was both dose- and time-related. The highest of the three doses, 10 mg/kg/day, resulted in a time-related decrease in total serum calcium. This dose also caused a rapid but transient reduction in serum ionized calcium. The effect of EHDP on serum inorganic phosphate was biphasic. Administration of 2.5 mg/kg/day resulted in a time-related elevation in this parameter, whereas the 10 mg/kg/day dose resulted in a time-related hypophosphatemic response. There were no significant drug-related changes in tibial fat-free dry weight, ash weight, total calcium or total phosphorus values. However, administration of 2.5 and 10 mg/kg/day EHDP resulted in increased osteoid tissue as measured histologically. These results are compared with data from other EHDP studies, and discussed in relation to the maturity and growth-state of the experimental animals.
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  • 9
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    Calcified tissue international 23 (1977), S. 13-17 
    ISSN: 1432-0827
    Keywords: Dental calculus ; Glycopeptide ; Chemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary A method is described for the isolation and purification of a sulphated glycopeptide from human supragingival calculus. The compound was isolated after using EDTA treatment, 2 M CaCl2 extraction, proteolytic digestion, ethanol precipitation, and finally purified by DEAE cellulose chromatography. It migrated as a single component on cellulose acetate electrophoresis, and chemical and infrared spectral analysis showed the presence of covalently attached sulphate groups. The sulphated glycopeptide was distinguished from being a sulphated glycosaminoglycan.
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  • 10
    ISSN: 1432-0975
    Keywords: Key words Otolith ; Chemistry ; ICP-MS ; Stock discrimination ; Epinephelus striatus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences
    Notes: Abstract  We examined the utility of otolith minor and trace element chemistry, assayed with inductively coupled plasma mass spectrometry (ICP-MS), as a means of delineating population structure in the Nassau grouper (Epinephelus striatus). We characterized the elemental composition of otoliths collected in 1993 from three locations in Exuma Sound, Bahamas and from Glover Reef, Belize in 1995. A single location in Exuma Sound was sampled in 1994 to test temporal variability in otolith composition. Five elements (Ca, Zn, Sr, Ba and Pb) were routinely detected, at levels significantly above background, by solution-based ICP-MS. Results from analysis of variance of elemental data, expressed as a ratio to Ca, indicated that there were no significant differences among the Exuma locations for any element, but significant variability was found between Glover Reef and the pooled Exuma localities for Zn/Ca, Sr/Ca and Ba/Ca ratios. Significant inter-annual differences at one Exuma Sound location was restricted to Ba/Ca ratios. Discriminant function analysis correctly classified 86% and 95% of the Belize and pooled Exuma sites, respectively. Otoliths from Belize were characterized by low Zn/Ca and high Ba/Ca and Pb/Ca ratios compared to otoliths from fish collected in Exuma Sound. Although differences in Ba levels may be related to upwelling at Glover Reef, more data are needed to definitely link otolith composition with regional differences in water chemistry.
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  • 11
    ISSN: 1432-0983
    Keywords: DNA amplification ; Mitochondrial DNA ; Somatic hybrid ; Gramineae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Somatic hybrid cell lines of Pennisetum americanum + Panicum maximum, and of Pennisetum americanum + Saccharum officinarum display unique mitochondrial DNA (mtDNA) restriction patterns suggestive of mitochondrial fusion and recombination. Apparent recombinant fragments of the hybrids were recovered, cloned, and hybridized to parental and somatic hybrid mtDNAs. In each somatic hybrid, “novel” fragments were found to be present at low copy number in one or both of the parental mtDNAs, and amplified 15–30 times in the hybrids. In pearl millet-sugarcane somatic hybrid cells, the amplification does not appear to involve enhanced recombination. The presumably amplified restriction fragment of the pearl millet-Guinea grass somatic hybrids is a junction fragment of a repeat, present in low copy number in both parents, and in high copy number in the hybrids. Thus protoplast and probable mitochondrial fusion results in a marked shift in the direction of mtDNA recombination events. We conclude that amplification of parental mtDNA fragments is a common event in somatic hybrid cells of these Gramineae.
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  • 12
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    Journal of molecular evolution 15 (1980), S. 79-101 
    ISSN: 1432-1432
    Keywords: Molecules ; Interstellar ; Chemistry ; Isotopes ; Solar system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The study of interstellar molecules broadly includes two areas of interest. One area uses the unique ability of molecules to act as probes of the physical conditions in the cold, dense, visually opaque component of the interstellar medium. The physical properties of this and other components of the interstellar medium are summarized. The other area deals with the chemistry of interstellar molecules, recent aspects of which are emphasized in this review. Gas-phase chemistry, shock chemistry, and grain surface chemistry are discussed in the context of recent observations. No present observations suggest that surface reactions are relevant, but neither can they be ruled out. Ion-molecule reactions are clearly operative, at least for the simpler species. Chemical isotope fractionation is reviewed, andd it is concluded that the complexities of the chemistry allow no cosmological conclusions to be drawn from observations of deuterium in interstellar molecules, while the presence of13C in interstellar molecules permits an estimate of the12C/13C ratio which is consistent with the current concepts of the nucleosynthesis history of the Galaxy. Possible connections between interstellar molecules and the early molecular history of the solar system are discussed.
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  • 13
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    Pure and applied geophysics 118 (1980), S. 128-151 
    ISSN: 1420-9136
    Keywords: Galactic cosmic rays ; Solar proton events ; Particle precipitation ; Chemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract An assessment is made of the relative contribution of certain classes of energetic particle precipitation to the chemical composition of the middle atmosphere with emphasis placed on the production of odd nitrogen and odd hydrogen species and their subsequent role in the catalytic removal of ozone. Galactic cosmic radiation is an important source of odd nitrogen in the lower stratosphere but since the peak energy deposition occurs below the region where catalytic removal of O3 is most effective, it is questionable whether this mechanism is important in the overall terrestrial ozone budget. The precipitation of energetic solar protons can periodically produce dramatic enhancement in upper stratospheric NO. The long residence time of NO in this region of the atmosphere, where catalytic interaction with O3 is also most effective, mandates that this mechanism be included in future modelling of the global distribution of O3. Throughout the mesosphere the precipitation of energetic electrons from the outer radiation belt (60°≲Λ≲70°) can sporadically act as a major local source of odd hydrogen and odd nitrogen leading to observable O3 depletion. Future satellite studies should be directed at simultaneously measuring the precipitation flux and the concomitant atmosphere modification, and these results should be employed to develop more sophisticated models of this important coupling.
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  • 14
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    Aquatic sciences 51 (1989), S. 108-128 
    ISSN: 1420-9055
    Keywords: Chemistry ; mountain lakes ; silica ; acidity ; sediment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Alpine lakes in siliceous catchments of Tyrol and Carinthia (Austria) show signs of acidification. About 9% of the studied lakes have no alkalinity, more than 20% are below pH 6. About two thirds of all lakes have acid neutralizing capacities below 100 μeq 1−1. In spite of moderate precipitation acidity, some lakes show considerable concentrations of dissolved reactive aluminum during or shortly after snowmelt. High altitude lakes of the Alps are definitely more acidic than high mountain lakes in remote areas. Large differences in water and soil chemistry of nearby situated lakes were attributed to heterogeneities of bedrock geology. Paleolimnological investigations on former pH values of five lakes, based on diatom assemblages in the sediment, showed different developments: recent and past acidification, stable conditions, and alkalinization.
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  • 15
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    Accreditation and quality assurance 5 (2000), S. 409-413 
    ISSN: 1432-0517
    Keywords: Key words Metrology ; Comparisons ; Chemistry ; Standards
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract  After stressing the importance in the modern world of accurate and reproducible measurements, the actions taken by the Bureau International des Poids et Mesures to set up, together with the regional metrology organizations, a series of key comparisons are described. They are the technical foundation of a mutual recognition of national measurement standards arrangement prepared in conjunction with the National Metrology Institutes (NMIs). This arrangement also includes the recognition of calibration and measurement certificates issued by these institutes. Then, the consequences of this arrangement for trade are described. The case of chemical analysis is illustrated by the application of the Kyoto protocol on the reduction of greenhouse gases. But the global workload to be taken up by the International Committee of Weights and Measures, its Consultative Committee for Amount of Substance and the NMIs is huge.
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  • 16
    ISSN: 1423-0445
    Keywords: learning behaviour ; green leaf volatiles ; olfactometer ; electroantennogram ; Cruciferae ; Gramineae ; Zygophyllaceae ; Orthoptera ; Acrididae ; Schistocerca gregaria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Gregarious nymphs of the desert locust,Schistocerca gregaria (Forsk.) (Orthoptera: Acrididae) were more attracted to volatiles from mechanically damaged food plants used for rearing than to either the undamaged or damaged food plants not used as diet in Y-tube olfactometer assays. Comparative analysis of the volatile emissions from plants used for rearing and food plants not used for rearing,e.g. Sorghum bicolor, Pennisetum clandestinum, Schouwia thebaica, wheat (Triticum sp., var. ‘Nyangumi’),Zygophyllum simplex, Heliotropium undulatum andTribulus terrestris was carried out by GC, GC-EAD and GC-MS. Significant quantitative and qualitative differences were found in the volatile emissions and olfactory responses of nymphs in GC-EAD assays. Up to 33 compounds were identified in volatiles of the plants of which 9 evoked EAGs. EAG-active components included common green leaf compounds (E)-2-pentenal, (E)-2-hexenal, 4-methyl-3-pentenal, (E)-3-hexenyl acetate, (Z)-3-hexenyl acetate, (Z)-2-hexenyl acetate, (Z)-3-hexen-1-ol and (Z)-2-hexen-1-ol. (Z)-3-Hexenyl butyrate and (Z)-3-hexenyl isovalerate were detected in stimulatory amounts only in the volatiles ofS. thebaica. (E, Z)-2,6-Nonadienal was detected as a component in the volatiles ofT. terrestris and was highly stimulatory. In EAG assays with seven common green leaf volatiles, (Z)-3-hexenyl acetate was most stimulatory while hexanal was the least. No significant differences were recorded between antennal responses of males and females to the tested compounds. These results are discussed with regard to current hypotheses on host plant recognition through detection of their airborne volatiles and the learning behaviour by nymphs ofS. gregaria.
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  • 17
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    Calcified tissue international 14 (1974), S. 3-14 
    ISSN: 1432-0827
    Keywords: Hydroxyapatite ; Mineral ; Phase ; Chemistry ; Synthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Des diagrammes de phase d'équilibre ont été déterminés pour le système CaO-P2O5-H2O en utilisant des techniques de synthèse hydrothermique au cours de variatio nsde température allant de 300–600° et 2 Kb H2O de pression. De l'hydroxyapatite bien cristallisé a été synthétisé et caractérisé. De faibles variations de paramètres de la maille cristalline, liées à la température de synthèse et composition globale du matériel initial, ont été déterminées. Des conditions chimiques précises sont nécessaires pour obtenir de l'apatite, en tant que seule phase solide en équilibre dans la solution. Les résultats de diagramme de phase d'équilibre sont comparés avec ceux obtenus dans des milieux synthétiques.
    Abstract: Zusammenfassung Es wurden Gleichgewichts-Phasendiagramme für das System CaO-P2O5-H2O bestimmt, indem hydrothermale Synthese-Techniken im Temperaturbereich von 300–600° und bei einem Druck von 2 Kb H2O verwendet wurden. Es wurde gut-kristallisiertes Hydroxyapatit erzeugt und charakterisiert. Es wurden geringe Unterschiede in den Parametern der Zelleinheiten festgestellt, welche von der angewandten Temperatur und der Zusammensetzung des Startmaterials abhingen. Es waren genaue chemische Bedingungen nötig, um Apatit als die einzige feste Phase im Gleichgewicht mit der Lösung zu erhalten. Die Resultate der Gleichgewichts-Phasendiagramme werden mit früheren Untersuchungen mit der Synthesetechnik verglichen.
    Notes: Abstract Equilibrium phase diagrams have been determined for the system CaO-P2O5-H2 using hydrothermal synthesis techniques in the temperature range 300–600° and 2 Kb H2O pressure. Well-crystallized hydroxyapatite has been produced and characterized. Small variations in unit cell parameters dependent on temperature of synthesis and bulk composition of the starting materials have been determined. Precise chemical conditions were required to obtain apatite as the only solid phase in equilibrium with solution. Equilibrium phase diagram results are compared with previous synthetic investigations.
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  • 18
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    Calcified tissue international 7 (1971), S. 150-162 
    ISSN: 1432-0827
    Keywords: Uranium ; Bone ; Distribution ; Fission ; Chemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Une concentration moyenne de 2.4×10−8 g U/g de cendre a été obtenue à partir de l'os humain normal. La microdistribution de l'uranium dans l'os indique que cet élément est surtout limité à surface de l'endoste et, en particulier, aux surfaces de l'os lamellaire et aux parois des canaux de Havers, ouverts dans l'os corticol. Cette répartition suggère que l'uranium se présente sous une forme chimique impropre à son incorporation dans l'apatite osseux: il ne semble donc pas exister une distribution diffuse significative de l'uranium dans l'os.
    Abstract: Zusammenfassung Eine mittlere Konzentration von 2,4×10−8 g Uran/g Asche wurde in normalen menschlichen Knochen gefunden. Die Feinverteilung von Uran im Knochen zeigt, daß dieses Element hauptsächlich an der endostalen Oberfläche vorkommt, insbesondere an der Oberfläche des trabeculären Knochens und an den Wänden der offenen Haversschen Kanäle im kortikalen Knochen. Diese Verteilung läßt vermuten, daß Uran in einer chemischen Form vorliegt, welche sich für den Einbau in das Knochenapatit nicht eignet. Daraus folgt, daß keine signifikante diffuse Verteilung des Urans innerhalb des Knochens vorliegt.
    Notes: Abstract A mean concentration of 2.4×10−8 g U/g ash has been obtained for normal human bone The microdistribution of uranium in bone indicates that this element is mainly restricted to endosteal surfaces; in particular the surfaces of trabecular bone and the walls of open Haversian canals in cortical bone. This distribution suggests that uranium is present in a chemical form that is not acceptable for incorporation into bone apatite and consequently there does not appear to be a significant diffuse distribution of uranium throughout bone.
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  • 19
    ISSN: 1432-0827
    Keywords: Morphology ; Glycosaminoglycans ; Cartilage ; Chemistry ; Audioradiography ; Healing
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Une perte de substance ostéo-cartilagineuse, de taille limitée et identique, est réalisée chez le lapin adulte et la cicatrisation est étudiée histologiquement et par autoradiographie après marquagein vitro au35S-sulfate. Une analyse microchimique est pratiquée pour le contenu et la composition en glycosaminoglycanes. 1. Entre la première semaine et la 4ème et 8ème semaine, un tissu conjonctif non-métachromatique se différencie en un cartilage métachromatique et la quantité de sulfate de chondroitine augmente de façon significative aux dépens des glycoprotéines. 2. Jusqu'à la 4ème semaine, la perte de substance est surtout comblée par de l'os néoformé: après cette période, la région est comblée au delà de la limite de la surface articulaire. 3. Le cartilage hyalin, ressemblant morphologiquement, autoradiographiquement et chimiquement au cartilage articulaire, en ce qui concerne la distribution en glycosaminoglycanes, constitute la surface articulaire de la perte de substance comblée dans un tiers des cas après 8 semaines. Le cartilage hyalin s'observe surtout dans les régions où de l'os néoformé a comblé la cavité médullaire. 4. Dans les deux tiers des cas, après 8 semaines, les surfaces articulaires des zones comblées comportent, non seulement du cartilage, mais aussi du tissu fibreux se formant essentiellement sur les parties latérales et dans les régions, où la cavité médullaire, fliant face, à la surface articulaire, n'a pas été comblée par du tissue osseux. La fraction glycoprotéique augmente par rapport à la fraction chondroitine sulfate. 5. Dans la majorité des cas, après 20 semaines, le cartilage néoformé subit des phénomènes dégénératifs, qui se traduisent par une diminution en chondroitine sulfate.
    Abstract: Zusammenfassung Bei ausgewachsenen Kaninchen wurde ein begrenzter, standardisierter, osteochondraler Defekt hervorgerufen, und das regenerierte Gewebe wurde histologisch und autoradiographisch durch Markierung in vitro mit35S-Sulfat und durch mikrochemische Bestimmung des Gehaltes und der Zusammensetzung der Glykosaminglykane untersucht. Die wichtigsten Befunde waren: 1. Zwischen 1 und 4–8 Wochen veränderte sich nichtmetachromatisches Bindegewebe zu metachromatisch gefärbtem Knorpel, und der Anteil an Chondroitin-Sulfat nahm auf Kosten der Glykoproteine signifikant zu. 2. Bis zu 4 Wochen war der Hauptteil des defekten Gebietes mit neugebildetem Knochen gefüllt; nach dieser Zeit lag dieser Bezirk oberhalb der Verknöcherungsgrenze in Richtung der Gelenkoberfläche. 3. Nach 8 Wochen bestand die Gelenkoberfläche des defekten Gebietes in einem Drittel der Fälle aus hyalinem Knorpel, der morphologisch, autoradiographisch und chemisch dem Gelenkknorpel in Bezug auf die Verteilung von Glykosaminoglykanen glich. Hyaliner Knorpel wurde hauptsächlich an Stellen beobachtet, wo neugebildeter Knochen die Markhöhle geschlossen hatte. 3. Nach 8 Wochen bestand die Gelenkoberfläche des defekten Gebietes in einem Drittel der Fälle aus hyalinem Knorpel, der morphologisch, autoradiographisch und chemisch dem Gelenkknorpel in Bezug auf die Verteilung von Glykosaminoglykanen glich. Hyaliner Knorpel wurde hauptsächlich an Stellen beobachtet, wo neugebildeter Knochen die Markhöhle geschlossen hatte. 4. Nach 8 Wochen bestanden Teile der Gelenkoberfläche des Defektes in zwei Dritteln der Fälle nicht nur aus Knorpel, sondern auch aus fibrösem Gewebe, welches vor allem in den seitlichen Teilen des Defektes und an Stellen vorlag, wo die Markhöhle gegenüber der Gelenkoberfläche nicht mit Knochengewebe verschlossen worden war. Die Glykoproteinfraktion nahm im Vergleich zur Chondroitin-Sulfatfraktion zu. 5. Nach 20 Wochen zeigten sich in den meisten Fällen bei neugebildetem Knorpel degenerative Veränderungen, welche durch eine gewisse Abnahme des Chondroitin-Sulfats wiedergegeben wurden.
    Notes: Abstract A limited, standardized osteochondral defect was created in adult rabbits and the regenerated tissue was examined histologically and autoradiographically after labellingin vitro with35S-sulphate, and microchemically for its content and composition of glycosaminoglycans. The principal findings were: 1. Between 1 week and 4 to 8 weeks, non-metachromatic connective tissue differentiated to metachromatically stained cartilage, and the proportion of the chondroitin sulphate increased significantly at the expense of the glycoproteins. 2. Up to 4 weeks, the major part of the defect area was filled with newly formed bone; after this time, the area lay above the level of the “tidemark”, towards the articular surface. 3. Hyaline cartilage with morphological, autoradiographic and chemical resemblance to the articular cartilage in terms of the distribution of glycosaminoglycans constituted the articular surface of the defect area in one-third of the cases at observation times after 8 weeks. Hyaline cartilage was observed mainly in areas where newly formed bone had closed the medullary cavity. 4. In two-thirds of the cases, after 8 weeks, parts of the articular surface of the defect consisted not only of cartilage but also of fibrous tissue, occurring mainly in the lateral parts of the defect and in areas where the medullary cavity facing the articular surface had not been sealed by bone tissue. The glycoprotein fraction increased relative to the chondroitin sulphate fraction. 5. In most cases after 20 weeks, newly-formed cartilage underwent degenerative changes, which were reflected in some reduction of the chondroitin sulphate.
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  • 20
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    Calcified tissue international 8 (1971), S. 228-236 
    ISSN: 1432-0827
    Keywords: Skin ; Calcinosis ; Keratin ; Chemistry ; X-ray diffraction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Des études histologiques antérieures ont montré que le follicle pileux est particulièrement susceptible de se calcifier, lorsque la peau de rats hypercalcémiques est lésée. Des analyses chimiques et par diffraction aux rayons X du follicule ont confirmé ce résultat. — En se basant sur l'augmentation du calcium et du phosphore, les calcifications débutent dans le tissue folliculaire 6–12 h après une blessure d'intensité moyenne de la peau de rats, ayant reçu du dihydrotachysterol (DHT), et 24–48 h après une blessure similaire chez des rats non injectés. Les diagrammes de diffraction aux rayons X sont diffus. Trois heures après la blessure, on note une augmentation du calcium du tissu folliculaire qui ne semble pas en rapport avec le DHT qui traduit probablement une liaison de calcium plutôt qu'un dépot minéral.
    Abstract: Zusammenfassung Frühere histologische Untersuchungen haben gezeigt, daß der Haarfollikel besonders anfällig für Verkalkungen ist, wenn die Haut von hypercalcämischen Ratten verletzt wird. Dieses Resultat wurde nun durch direkte chemische Bestimmungen und Röntgendiffraktions-analysen von Follikelgewebe bestätigt. Aufgrund der erhöhten Calcium- und Phosphatwerte kann gesagt werden, daß nach einer leichten Quetschung der Haut von Ratten, die mit Dihydrotachysterol (DHT) behandelt wurden, im Haarfollikelgewebe nach 6–12 Std Mineral-ablagerungen stattfanden, wogegen Kontrollratten mit der gleichen leichten Hautverletzung diese Ablagerungen erst nach 24–48 Std zeigten. Röntgendiffraktionsanalysen ergaben ein diffuses Apatit-Muster. Innerhalb 3 Std nach der Verletzung wurde ein Anstieg des Calcium-gehaltes im Follikelgewebe beobachtet, der nicht im Zusammenhang mit der DHT-Behandlung stand, also nicht eine Mineralablagerung, sondern eher eine Bindung von Calcium widerspiegelte.
    Notes: Abstract Previous histological investigations have shown that the hair follicle is particularly susceptible to mineralization when the skin of hypercalcaemic rats is injured. Direct chemical and X-ray diffraction analyses of follicle tissue have now confirmed this finding. As judged by increases in both calcium and phosphorus, mineral deposits began to form in hair follicle tissue 6–12 h after a mild crush injury to the skin of rats dosed with dihydrotachysterol (DHT), and 24–48 h after a similar injury to the skin of non-dosed rats. X-ray diffraction gave a diffuse apatite pattern. Within 3 h of injury there was a rise in the calcium content of follicle tissue which was not related to DHT-dosing and which was probably a reflection of calcium binding rather than mineral deposition.
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  • 21
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    Calcified tissue international 8 (1971), S. 304-319 
    ISSN: 1432-0827
    Keywords: Chemistry ; Calcium ; Phosphate ; Solubility ; Computer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Un programme d'ordinateur a été mis au point pour calculer les activités ioniques du calcium et l'orthophosphate dans un grand nombre de solutions. Dans le cas de solutions synthétiques, les calculs sont vérifiés en comparant les valeurs de pH, obtenues par ordinateur, avec celles observées expérimentalement. Des essais de ce type, avec des solutions possèdant des concentrations de calcium et d'orthophosphate trouvées dans les liquides biologiques et à des valeurs de pH variant de 3.00 à 10.00, indiquent que le programme est adapté pour des applications biologiques. Le programme n'est pas effectif pour des solutions, dans les lesquelles l'ion bromure est la source principale de la force ionique, sans doute, par manque d'équation étendue de Debye-Hückel dans ces circonstances. Aucune formation de complexe de phosphate de sodium n'a été notée à des concentrations biologiques normales.
    Abstract: Zusammenfassung Es wurde ein Computer-Programm ausgearbeitet, um die Ionenaktivitäten von Calcium und Orthophosphat in einer breiten Varietät von Lösungen zu berechnen. Die Berechnungen wurden bei synthetischen Lösungen durch Vergleiche zwischen den auf diese Weise errechneten pH-Werten und den experimentell gefundenen kontrolliert. Diese Art Kontrollen mit Calcium-und Orthophosphatkonzentrationen, wie sie in biologischen Flüssigkeiten gefunden werden, und mit pH-Werten zwischen 3,0 und 10,0 wies darauf hin, daß das Programm für biologische Anwendungen geeignet war. Das Programm konnte nicht benützt werden für solche Lösungen, bei welchen hauptsächlich das Bromidion zur Einstellung der Ionenstärke verwendet wurde, vermutlich weil die erweiterte Debye-Hückel-Gleichung unter diesen Umständen nicht anwendbar ist. Die Bildung eines Natriumphosphat-Komplexes unter normalen biologischen Konzentrationen konnte nicht nachgewiesen werden.
    Notes: Abstract A computer program has been designed to calculate the ionic activities of calcium and orthophosphate in a wide variety of solutions. In the case of synthetic solutions the calculations were checked by comparing the computed pH values with those observed experimentally. Tests of this type with solutions having the concentrations of calcium and orthophosphate found in biological fluids and with pH values ranging from pH 3.0–10.0 indicated that the program was suitable for biological applications. The program was not effective for solutions in which the bromide ion was a principal source of ionic strength probably because of the failure of the extended Debye-Hückel equation under those circumstances. No evidence for the formation of any sodium phosphate complex at normal biological concentrations could be found.
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  • 22
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    Calcified tissue international 10 (1972), S. 171-197 
    ISSN: 1432-0827
    Keywords: Amorphous ; Crystalline ; Calcium phosphate ; Chemistry ; Composition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Des échantillons non lavés de phosphate de calcium amorphe (ACP) contiennent une fraction labile, non remplaçable, riche en phosphate acide avec un rapport Ca/P faible: cette fraction est perdue de façon irréversible au cours du lavage. De l'ACP frais, précipité entre pH 6.6–10.6, varie dans un rapport molaire Ca/P de 1.18 à 1.50 et dans un rapport HPO 4 2− /P total de 33.0% à 10.1%. A pH 7.40, de l'ACP frais a un rapport molaire Ca/P de 1.36±0.02 et contient 22.8 (±2.2)% HPO 4 2− . Les résultats obtenus avec du précipité non lavé ne peuvent s'expliquer par du Ca2+ emprisonné et de l'HPO 4 2− ou du Na+, Cl− et CO 3 2− exogènes. Les phosphates de calcium amorphes constituent une classe de sels ayant des caractères chimiques variables et des propriétés physiques identiques, comparables au verre. Le CaHPO4·xH2O non cristallin peut être un ACP, surtout au cours des phases précoces de formation. A des pH physiologiques, l'ACP se transforme en petits cristaux applatis contenant de fortes quantités de phosphate acide facilement remplaçable. Le fait de laver la couche de surface produit un changement chimique dans les nouveaux cristaux: des cristaux non lavés donnent des diagrammes de diffraction d'apatite peu cristallins, ainsi que des spectres infra-rouges peu nets, intermédiaires entre des apatites et du phosphate octocalcique. Des explications structurales sont proposées et les compositions minérales amorphe/cristalline de l'os et du cartilage sont recalculées.
    Abstract: Zusammenfassung Ungewaschene Proben von amorphem Calciumphosphat (ACP) enthalten eine unersetzliche labile Fraktion, welche reich an saurem Phosphat ist und ein niederes Ca/P-Verhältnis hat und welche während des Waschprozesses unwiderruflich verloren geht. Natives ACP, welches im pH-Bereich 6,6–10,6 ausgefällt wurde, variierte im molaren Ca/P-Verhältnis zwischen 1,18 und 1,50 und in HPO 4 2− /totales P zwischen 33,0 und 10,1%. Bei pH 7,40 hatte natives ACP ein molares Ca/P-Verhältnis von 1,36±0,02 und enthielt 22,8 (±2,2)% HPO 4 2− . Die Werte beim ungewaschenen Niederschlag rühren weder von aus dem Überstand aufgenommenem Ca2+ und HPO2−, noch von außen kommendem Na+, Cl− und CO 3 2− her. Die amorphen Calciumphosphate werden als eine Klasse von Salzen erkannt, welche veränderliche chemische, aber identische glasartige physicochemische Eigenschaften haben. Nicht kristallines CaHPO4·xH2O kann auch ein ACP sein, besonders in den frühen Bildungsstadien. Bei physiologischem pH verwandelt sich ACP in kleine plattenförmige Kristalle, welche große Mengen von leicht ersetzbarem saurem Phosphat enthalten. Das Waschen dieser Oberflächenschicht erzeugte chemische Veränderungen in den resultierenden Kristallen; ungewaschene Kristalle zeigten ein Diffraktionsmuster, das nur schwach demjenigen des kristallinen Aspatites glich, aber ein schlecht aufgelöstes Infrarotspektrum, welches zwischen Apatit und Octocalciumphosphat war. Es werden strukturelle Erklärungen für alle diese Phenomena diskutiert, und revidierte amorph/kristalline Mineralzusammensetzungen von Knochen und Knorpel wurden neu berechnet.
    Notes: Abstract Unwashed samples of amorphous calcium phosphate (ACP) contain an irreplaceable labile fraction, rich in acid phosphate and low in Ca/P ratio, which is irreversibly lost during the washing process. Native ACP precipitated in the pH range 6.6–10.6 varied in Ca/P molar ratio from 1.18 to 1.50 and in HPO 4 2− /total P from 33.0% to 10.1%. At pH 7.40, native ACP had a Ca/P molar ratio of 1.36±0.02 and contained 22.8 (±2.2)% HPO 4 2− . Unwashed precipitate data could not be attributed to either trapped supernatant Ca2+ and HPO 4 2− or extraneous Na+, Cl−, and CO 3 2− . The amorphous calcium phosphates are recognized as a class of salts having variable chemical but identical glass-like, physicochemical properties. Non-crystalline CaHPO4·xH2O may also be an ACP, especially during early formative stages. At physiological pH, ACP transforms to small platy crystals containing large amounts of readily-replaceable acid phosphate. Washing this surface layer produced chemical alterations in the resultant crystals; unwashed crystals had poorly-crystalline apatitic diffraction patterns but exhibited poorly-resolved infrared spectra intermediate between apatite and octacalcium phosphate. Structural explanations for all these phenomena are discussed, and revised bone and cartilage amorphous/crystalline mineral compositions have been re-calculated.
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  • 23
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    Calcified tissue international 23 (1977), S. 39-44 
    ISSN: 1432-0827
    Keywords: Dental cementum ; Collagen ; Protein ; Chemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Cyanogen bromide (CNBr) peptides were prepared of the insoluble collagen of bovine dental cementum. Following chromatographic separation, the peptides were identified by their amino-acid composition. Type I collagen ([α1(I)]2α2) accounted for more than 90% of the organic matrix, while Type III collagen ([α1(III)]3) was present at a level of approximately 5%. Amino-acid analyses revealed that the CNBr peptides from α1(I) and α2 chains of cementum closely resembled the corresponding peptides from calf skin. The only systematic difference was a higher level of hydroxylation of prolyl and lysyl residues of the cementum peptides.
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  • 24
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    Calcified tissue international 23 (1977), S. 87-94 
    ISSN: 1432-0827
    Keywords: Calcium ; Osteoporosis ; Lactation ; Chemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The calcium homeostatic mechanism was challenged in adult female rats by feeding them a calcium-deficient diet containing oxalate, and by subjecting them to pregnancy and lactation. The regimen caused a substantial weight loss, especially in those animals which reared their young well. Severe hypocalcaemia was observed in the lactating rats. Serum-P was slightly elevated. The content of hydroxyproline in serum was considerably elevated, reflecting the degree of calcium deprivation. Serum proteins were least influenced. The calcium depriving regimen reduced the growth of long bones, but did not stop it. The ash content of the bones was considerably reduced, the degree of reduction depended on the degree of calcium deprivation. Ash as percentage of total bone organ was reduced, but not to the same extent as total ash. Analyses of different parts of femur showed that the proximal and distal parts had lost more bone mineral than the diaphyseal shaft. The ash content of cortical bone tissue from the femur was estimated by a volumetric method. No differences were observed between test groups and controls, indicating that no measurable amounts of bone mineral had been removed from the walls of the vascular canals or by osteocytic osteolysis. Planimetric determinations on cross sections from femora disclosed that a great amount of bone had been removed from the endosteal surface of the diaphysis, while the periosteal surface demonstrated reduced bone apposition.
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  • 25
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    Calcified tissue international 8 (1971), S. 197-210 
    ISSN: 1432-0827
    Keywords: Fluorescence ; Calcium ; Collagen ; Chemistry ; Bone ; Dentine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Des composants fluorescents de l'os et la dentine sont séparés des hydrolysats alcalins de leur marice sur des colonnes Sephadex C25 CM d'échange cationique. Les concentrations en fluorescence et le spectre d'excitation (λ max 330 nm) et d'émission (λ max 395 nm) sont les mêmes que ceux observés au niveau des matrices intactes et gélatinisées. Les paramètres de fluorescence ne sont pas altérés par hydrolyse. La filtration sur gel à l'aide de colonnes Sephadex G 10 perment de différencier le matériel isolé en deux composants, ayant la même fluorescence et la même absorption UV. La fluorescence est indépendante de pH de 3.5–9.5. Des études de dialyse et de filtration sur gel de matrices gélatinisées indiquent une association étroite du matériel fluorescent avec les chaines polypeptidiques de collagène.
    Abstract: Zusammenfassung Fluorescierende Bestandteile aus Knochen und Dentin wurden in Sephadex C25 CM Kationen-Austauschersäulen von alkalischen Hydrolysaten ihrer Matrices getrennt. Die Fluorescenzintensitäten sowie die Erregungs- (λ max 330 nm) und Emissions- (λ max 395 nm) Spektren waren dieselben wie bei intakten und gelatinisierten Matrices. Die Fluorescenzparameter wurden durch die Hydrolyse nicht verändert. Eine Gelfiltration über Sephadex-G10-Säulen trennte das isolierte Material in 2 Komponenten auf, welche gleiche Fluorescenz- und UV-Absorptionseigenschaften zeigten. Im pH-Bereich zwischen 3,5 und 9,5 war die Fluorescenz unabhängig vom pH. Dialysierversuche sowie Gelfiltrationsexperimente mitden gelatinisierten Matrices zeigten eine starkgefügte Bindung des fluorescierenden Materials mit den Polypeptidketten des Kollagens.
    Notes: Abstract Fluorescent components in bone and dentine were separated from alkaline hydrolysates of their matrices on Sephadex C25 CM cationic exchange columns. The fluorescence levels, and the excitation (λ max 330 nm) and emission (λ max 395 nm) spectra, were the same as those observed in the intact and gelatinised matrices. The fluorescence parameters were unaltered by the hydrolysis procedure. Gel filtration on Sephadex G. 10 columns further resolved the isolated material into two components with the same fluorescence and UV absorption properties. The fluorescence was independent of pH over the range 3.5–9.5. Dialysis and gel filtration studies on the gelatinised matrices indicated a firmly-bonded association of the fluorescent material with the collagen polypeptide chains.
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  • 26
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    Calcified tissue international 12 (1973), S. 125-136 
    ISSN: 1432-0827
    Keywords: Mineralization ; Molt ; Isopod ; Chemistry ; Light microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Au cours de la phase inhabituelle de mue d'un isopode d'eau courante,Lirceuts brachyrus, la moitié postérieure de l'exosquelette est éliminée 24 heures avant la moitié antérieure. A ce stade, une reminéralisation se développe dans la partie postérieure alors que la partie antérieure est dans un stade de pré-mue. Le pourcentage de différence en calcium dans les deux moitiés à mi-mue et mue complète est respectivement de 22% (p〈0.01) et 33% (p〈0.01), indiquant une complexation du calcium pendant la mue. La rapidité de la reminéralisation est illustrée par le fait que le contenu minéral total double dans la partie postérieure entre la mi-mue et la mue totale et dans la partie antérieure entre la fin de la mue et un jour après. Le carbonate de calcium, sous forme de calcite, a pu être identifié par diffraction électronique de coupes fines des téguments.
    Abstract: Zusammenfassung Während der ungewöhnlichen Häutungssequenz des Frischwasser-IsopodenLirceus brachyurus (Harger) wird die hintere Hälfte des äußeren Skeletts 24 Std vor der vorderen Hälfte abgestoßen. In der halbgehäuteten Phase erfolgt Remineralisation im hinteren Teil, während der vordere Teil in einem Vorhäutungszustand ist. Der prozentuale Unterschied des Calciums in den zwei Hälften bei Halb- und Vollhäutungszustand ist 22% (p〈0,01) bzw. 33% (p〈0,01), was andeutet, daß Calcium während der Häutung abgesondert wird. Die Geschwindigkeit der Remineralisation erhellt aus der Tatsache, daß sich der Gesamtmineralgehalt im hinteren Teil zwischen Halt- und Vollhäutung, in der vorderen Hälfte jedoch zwischen Endhäutung und einem Tag nach der Häutung verdoppelt. Calciumcarbonat in kristalliner Calcitform wurde mittels Elektronendiffraktion von dünnen Hautschnitten nachgewiesen.
    Notes: Abstract During the unusual molt sequence of the fresh-water isopod,Lirceus brachyrus (Harger), the posterior half of the exoskeleton is shed 24 hours before the anterior half. At the half-molt stage, occurs in the posterior part while the anterior portion is in a pre-molt condition. The percentage difference in calcium in the two halves at half-molt and full-molt is22 (p〈0.01) and33 (p〈0.01) respectively, an indication that calcium is sequestered during The rapidity of remineralization is illustrated by the fact that the total mineral content doubles in the posterior part between half and full molt and in the anterior half between the end of molt and one day after ecdysis. Calcium carbonate in the calcite cystalline form was demonstrated by electron diffraction of thin sections of the integument.
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    Calcified tissue international 13 (1973), S. 259-270 
    ISSN: 1432-0827
    Keywords: Fluorapatite ; Exchange ; Chemistry ; Crystallography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Un échantillon minéral provenant de Burgess, Canada s'est révélé être un speciment exceptionnellement pur de fluoroapatite après analyse chimique et cristallographique. La composition globale de cet échantillon est la suivante: $$(Ca^2 )9.98(Sr^{2 + } ,Na^ + ,K^ + ,Mg^{2 + } )0.02(PO_4^{3 - } )5.98(HCO_3^ - ,CO_3^{2 - } )0.02(F^ - )2$$ . L'axe cristallographique C est de 6.865 A et l'axe a de 9.374 A. Des expériences d'échanges réalisés à l'aide de45Ca,32P et18F indiquent la présence de gros cristallites de surface spécifique de l'ordre de 1 m2/g. Il apparait que l'interprétation physique des processus d'échange ne nécessite pas l'existence de compartiments séparés, avec chacun son propre facteur cinétique, les échanges semblent être simplement liés à un changement exponentiel dans l'énergie libre de la réaction. Pour la réaction suivante: $$(Ca)_5 (PO_4 )_3 OH solide + (F^ - ) \rightleftarrows (Ca)_5 (PO_4 )_3 F solide + (OH^ - )$$ , la constante thermodynamique de 101.26 a été calculée, suggérant que le fluorapatite se forme toujours aux dépens de l'hydroxyapatite dans des conditions physiologiques. Cette transformation se continue en abaissant le pH.
    Abstract: Zusammenfassung Eine Mineralprobe aus Burgess, Kanada, erwies sich nach chemischer und kristallographischer Analyse als außergewöhnlich reines Fluorapatit. Die Gesamtzusammensetzung entspricht: $$(Ca^{2 + } )_{9,98} (Sr^{2 + } ,Na^ + ,K^ + ,Mg^{2 + } )_{0,02} (PO_4^{3 - } )_{5,98} (HCO_3^ - ,CO_3^{2 - } )_{0,02} (F^ - )_2 $$ . Die kristallographische c-Achse wurde bestimmt und ergab 6,865 Å, und die a-Achse ergab 9,374 Å. Austauschwerte, welche durch Anwendung von45Ca,32P und18F erhalten wurden, deuteten auf große Kristalliten mit einer spezifischen Oberfläche von ca. 1 m2/g. Die Befunde deuten darauf hin, daß für die physikalische Erklärung des Austauschvorganges keine separaten Kompartimente mit eigenen kinetischen Faktoren nötig sind, sondern daß der Austausch mit dem exponentiellen Wechsel in der freien Energie der Reaktion in einfacher Beziehung steht. Für die Reaktion $$(Ca)_5 (PO_4 )_3 OH_{in fester Form} + (F^ - ) \rightleftarrows (Ca)_5 (PO_4 )_3 F_{in fester Form} + (OH^ - )$$ wurde als thermodynamische Konstante 101,26 errechnet, was darauf deutet, daß unter physiologischen Bedingungen immer Fluorapatit auf Kosten von Hydroxyapatit entsteht. Diese Umwandlung wird erhöht, wenn das pH erniedrigt wird.
    Notes: Abstract A mineral specimen from Burgess, Canada, proved upon chemical and crystallographic analyses to be an exceptionally pure sample of fluorapatite. The over-all composition corresponds to $$(Ca^{2 + } )_{9.98} (Sr^{2 + } ,Na^ + ,K^ + ,Mg^{2 + } )_{0.02} (PO_4^{3 - } )_{5.98} (HCO_3^ - ,CO_3^{2 - } )_{0.02} (F^ - )_2 $$ . The crystallographic c-axis was determined to be 6.865 Å, and the a-axis 9.374 A. Exchange data obtained by employing45Ca,32P, and18F indicate the presence of large crystallites with a specific surface of the order of 1 m2/g. It is indicated that the physical interpretation of the exchange process does not require the existence of separate departments, each with its own kinetic factor, but that the exchange may be simply related to the exponential change in the free energy of the reaction. For the reaction $$(Ca)_5 (PO_4 )_3 OH_{solid} + (F^ - ) \rightleftarrows (Ca)_5 (PO_4 )_3 F_{solid} + (OH^ - )$$ the thermodynamic constant has been calculated to be 101.26, implying that fluorapatite always will form at the expense of hydroxyapatite under physiologic conditions. This transformation will be furthered by lowering the pH.
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  • 28
    ISSN: 1432-0827
    Keywords: Bacterial amphophile ; Purification ; Chemistry ; Resorption ; Ca influx ; Cyclic AMP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The bone resorptive factor and amphipathic antigen (AcA) previously identified by us in preparations fromActinomyces viscosus have been partially purified, characterized chemically, and compared. They elute at the same location on chromatography with Ac 22. The fatty acid composition of AcA and the bone resorptive factor is the same. Some differences in carbohydrate composition are observed. TheActinomyces factor does not affect calcium influx or cyclic AMP in isolated bone cells. Therefore it is concluded that AcA stimulates resorption either by gaining entrance into bone cells or by way of a yet undetermined second messenger.
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  • 29
    ISSN: 1432-203X
    Keywords: Gramineae ; GUS ; microprojectile bombardment ; pearl millet ; tissue culture ; transient gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Transient GUS (β-glucuronidase) expression was visualized in whole and sectioned embryos of Pennisetum glaucum (L.) R. Br. (pearl millet) after microprojectile bombardment with pMON 8678 DNA. Strongest GUS expression occurred in cells located in the center of GUS positive spots with decreasing intensity in surrounding cells. GUS positive cells could be seen up to 12 cell layers beneath the epidermis. Needle-like crystals of the GUS assay product were found throughout the cytoplasm of GUS positive cells. The number of GUS positive spots was correlated to the microprojectile spread pattern on the medium surface. Shorter bombardment distances (6.6 and 9.8 cm) and the standard accelerator speed gave the best results for transient expression but also caused maximum tissue damage. The speed and distance, however, had little influence on the ability of bombarded embryos to form compact callus. The developmental stage of the bombarded immature embryos was the determining factor in the formation of compact callus, from which plants were regenerated.
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  • 30
    ISSN: 1432-2048
    Keywords: Brachypodium ; Cereal ; Embryo (lectins) ; Gramineae ; Lectin (chemotaxonomy) ; Oryza (lectin) ; Triticeae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A survey of the occurrence of lectins in seeds from more than 100 grass species showed that all species belonging to the Triticeae tribe and the genera Brachypodium and Oryza contain lectins. All these lectins have the same sugar-binding specificity and are related to wheat-germ agglutinin, but to different degrees. Lectins from Triticeae species are immunologically indistinguishable from wheat lectin, whereas Brachypodium and rice lectins are only immunologically related to the wheat lectin. Attempts to detect lectin-deficient lines or varieties in wild and cultivated species of the three lectin-containing groups were unsuccessful. The possible use of lectins as a chemotaxonomic tool is discussed.
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  • 31
    ISSN: 1432-2048
    Keywords: Acids, dicarboxylic ; CO2 fixation ; Eriochloa ; Gramineae ; Photosynthesis
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    Topics: Biology
    Notes: Abstract C4-acid metabolism by isolated bundlesheath chloroplasts, mitochondria and strands of Eriochloa borumensis Hack., a phosphoennolpyruvate-carboxykinase (PEP-CK) species, was investigated. Aspartate, oxaloacetate (OAA) and malate were decarboxylated by strands with several-fold stimulation upon illumination. There was strictly light-dependent decarboxylation of OAA and malate by the chloroplasts, but the chloroplasts did not decarboxylate aspartate in light or dark. PEP was a primary product of OAA or malate decarboxylation by the chloroplasts and its formation was inhibited by 3-(3,4-dichlorophenyl)-1, 1-dimethylurea or NH4Cl. There was very little conversion of PEP to pyruvate by bundle-sheath chloroplasts, mitochondria or strands. Decarboxylation of the three C4-acids by mitochondria was light-independent. Pyruvate was the only product of mitochondrial metabolism of C4-acids, and was apparently transaminated in the cytoplasm since PEP and alanine were primarily exported out of the bundle-sheath strands. Light-dependent C4-acid decarboxylation by the chloroplasts is suggested to be through the PEP-CK, while the mitochondrial C4-acid decarboxylation may proceed through the NAD-malic enzyme (NAD-ME) system. In vivo both aspartate and malate are considered as transport metobolites from mesophyll to bundle-sheath cells in PEP-CK species. Aspartate would be metabolized by the mitochondria to OAA. Part of the OAA may be converted to malate and decarboxylated through NAD-ME, and part may be transported to the chloroplasts for decarboxylation through PEP-CK localized in the chloroplasts. Malate transported from mesophyll cells may serve as carboxyl donor to chloroplasts through the chloroplastic NAD-malate dehydrogenase and PEP-CK. Bundle-sheath strands and chloroplasts fixed 14CO2 at high rates and exhibited C4-acid-dependent O2 evolution in the light. Studies with 3-mercaptopicolinic acid, a specific inhibitor of PEP-CK, have indicated that most (about 70%) of the OAA formed from aspartate is decarboxylated through the chloroplastic PEP-CK and the remaining (about 30%) OAA through the mitochondrial NAD-ME. Pyruvate stimulation of aspartate decarboxylation is discussed; a pyruvate-alanine shuttle and an aspartate-alanine shuttle are proposed between the mesophyll and bundle-sheath cells during aspartate decarboxylation through the PEP-CK and NAD-ME system respectively.
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    Sexual plant reproduction 1 (1988), S. 25-27 
    ISSN: 1432-2145
    Keywords: Self-incompatibility ; Gramineae ; Two loci system ; Phalaris coerulescens ; Stigma proteins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Protein extracts from four self-incompatible genotypes of Phalaris coerulescens were subjected to analysis by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and ultra-thin isoelectric focusing. A comparison between stigma, root and leaf extracts showed that there was no significant difference in electrophoretic or isoelectric focusing patterns between the genotypes for both root and leaf proteins. However, stigma protein patterns did vary between genotypes especially within the molecular weight region of 43 000–97 000 and within the pI range 5–7. The stigma-specific changes strongly suggest a link between the self-incompatible genotype and these stigma proteins. However, because there are two loci involved, it is not yet possible to precisely assign particular proteins to each S- or Z-allele.
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    Sexual plant reproduction 7 (1994), S. 333-346 
    ISSN: 1432-2145
    Keywords: Antipodal cells ; Ultrastructural changes Functions ; Hordeum vulgare ; Gramineae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The antipodal cells have been the stepchildren in most investigations of the female gametophyte. In Hordeum vulgare cv. Bomi, three antipodal cells are originally developed chalazally but because of differential growth of the embryo sac they soon become laterally situated and their number increases to 35–50 cells and the shape, size and structure of the cells change in the time before as well as after fertilization. The cells persist until about 60–70 h after pollination. At that time, the embryo consists of about 12–15 cells and a cellularization of the nuclear endosperm has started peripherally. The size of nuclei, and especially nucleoli, in the antipodal cells increases tremendously in the investigated period and the amounts of organelles also change. The walls of antipodals are diversified depending on which cells they are separating, and wall invaginations are developed especially between antipodal cells and surrounding nucellar cells in the placental region. The mitochondria appear in various shapes in section view, very often as cups or dumbbells with a rim in the ends containing cristae and a thin cristae-free base. These bases are sometimes stretched out as thin parts and at last a simple parting occurs. Binary fissions of the plastids happen especially in the hours before and just after egg fertilization. ER is extraordinarily well developed in the whole period of investigation and many ribosomes are attached to the membranes. Dictyosomes form numerous vesicles, especially in the antipodals near the nucellar cells in the placental region. These ultrastructural details support the opinion that antipodal cells may play an important role in the embryo sac and are able to be responsible for the supply of nutrition for the whole gametophyte and take part in the supply of nutrition during embryo formation.
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    Plant cell reports 12 (1992), S. 26-28 
    ISSN: 1432-203X
    Keywords: Gramineae ; Secale cereale ; Somatic embryogenesis ; Polyembryony
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The progeny of polyembryonic Secale cereale L., was used to study the in vitro response of the immature embryos. The formation of embryogenic calli was very high, and this response and its distribution was statistically different to that shown by the normal regenerated plants and the original population. This behaviour seems to be related to a genetic condition which favours the presence of supernumerary embryos, in vivo as well as in vitro.
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  • 35
    ISSN: 1432-0983
    Keywords: Gramineae ; DNA transfer ; Organelle genomes ; Structural rearrangements
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    Topics: Biology
    Notes: Abstract The transfer of fragments of DNA from chloroplast genomes to mitochondrial genomes is considered to be a general phenomenon in higher plants. In the present study, Southern hybridization, together with amplification by PCR and DNA sequencing techniques, was used to examine the regions homologous to chloroplast rps19 in the mitochondrial genomes of several gramineous plants. In all the mitochondrial DNAs from the gramineous plants examined, except for that from wheat, the transferred fragments of chloroplast DNA were found to be maintained and the same junctions of mitochondrion-specific and chloroplast-like sequences were found at one terminus. This finding indicates that the transfer of the chloroplast sequence occurred in the distant past during the evolution of gramineous plants. Subsequent analysis revealed that the fragments had been variously rearranged among species with respect to the other terminus. Considering the current diversity of this one particular transferred fragment of chloroplast DNA, we propose that chloroplast-derived DNA sequences that have lost their original functions tend to be rearranged during evolution in mitochondrial genomes.
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  • 36
    ISSN: 1432-0983
    Keywords: Key words Chloroplast-derived (ct-derived) sequence ; Mitochondrial DNA (mtDNA) ; Gramineae ; Variation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Evidence for the transfer of DNA from the chloroplast to the mitochondrion has been reported in many higher plants and, in most cases, the transferred chloroplast genes do not have the ability to encode functional products as a consequence of base substitutions and/or multiple rearrangements. We reported previously that the sequence of one end of a chloroplast-derived (ct-derived) fragment of DNA that contained the rps19 and trnH genes has been maintained in most gramineous plants and that its presence seems to be correlated with gene expression in this region. In the present study, we have investigated whether or not the ct-derived sequences in mitochondrial DNA (mtDNA) from some gramineous plants and species of Oryza are conserved, and whether or not such conservation is related to gene expression in these regions. We identified two junctions between ct-derived and mitochondrial sequences that were conserved among some gramineous plants. Around these regions, we found a ct-derived gene for tRNA and the promoter of a mitochondrial gene on the ct-derived sequences, respectively, and these regions were transcribed through the junctions. This result indicates that the junctions and/or regions that are transcribed and functional in mitochondria have been strongly conserved and maintained during their evolution. In Oryza, some junctions between ct-derived and mitochondrial sequences were conserved and other junctions were not. These variations seem to have been caused by deletions and/or rearrangements, and appear to be specific to the type of genome. In the case of Oryza, the timing of deletions and/or rearrangements of ct-derived sequences is likely to have coincided with the divergence of the various genome types.
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    Theoretical and applied genetics 100 (2000), S. 1257-1266 
    ISSN: 1432-2242
    Keywords: Key words Chloroplast microsatellite ; Simple sequence length polymorphism (SSLP) ; Allelic diversity ; Rice (Oryza sativa) ; Gramineae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract  Primer pairs flanking ten chloroplast microsatellite loci, originally identified in Oryza sativa cv Nipponbare, were evaluated for amplification and allelic diversity using a panel of 13 diverse cultivars of rice (O. sativa), 19 accessions of wild rice (three O. officinalis, five O. latifolia, five O. minuta, four O. australiensis, one O. brachyantha and one O. ridleyi) and eight other Gramineae species (maize, teosinte, wheat, oat, barley, pearl millet, sorghum and sugarcane). Amplified products were obtained for all samples at nine out of ten loci. Among the rice cultivars, the number of alleles per locus ranged from one to four, with monomorphic patterns observed at five loci. The average polymorphism information content (PIC) value at the other five (polymorphic) loci was 0.54 among the 13 cultivars. When wild rice and the other Gramineae species were compared based on the proportion of shared alleles, their phylogenetic relationships were in agreement with previous studies using different types of markers; however, the magnitude of the differences based on chloroplast microsatellites underestimated the genetic distance separating these divergent species and genera. A sequence-based comparison of homologous regions of the rice and maize chloroplast genomes revealed that, while a high level of microsynteny is evident, the occurrence of actively evolving microsatellite motifs in specific regions of the rice chloroplast genome appears to be mainly a species or genome-specific phenomenon. Thus the chloroplast primer pairs used in this study bracketed mutationally active microsatellite motifs in rice but degenerate, interrupted motifs or highly conserved, mutationally inert motifs in distantly related genera.
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    Biochemical genetics 14 (1976), S. 897-904 
    ISSN: 1573-4927
    Keywords: polyploidy ; flavonoid synthesis ; flavone C-glycosides ; aneuploids ; Gramineae ; Briza
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Following a recent reidentification of the apigenin C-glycosides in diploid Briza media, the luteolin C-glycosides were reexamined and three acylated derivatives of a luteolin C-glycoside were found. In an attempt to identify the chromosome or group of chromosomes responsible for the change in flavonoid synthesis from 4′-hydroxy- in diploid plants to 3′,4′-dihydroxyflavone C-glycosides in autotetraploid plants, leaf flavonoids of artificially produced aneuploids of B. media were examined. Among these plants three different leaf flavonoid profiles were recognized: diploid, tetraploid, and a “modified” tetraploid pattern. All the aneuploids with the normal or “modified” tetraploid pattern were trisomic for one of the small acrocentric chromosomes. Induced polyploids of other Briza species were usually found to have similar flavonoid patterns in the two chromosome races. Flavonoid sulfates were found in three South American species but are absent from all the European species.
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    Biochemical genetics 28 (1990), S. 319-336 
    ISSN: 1573-4927
    Keywords: Zea mays ; Gramineae ; β-glucosidase ; null allelism ; immunoblotting ; electrophoresis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Maize β-glucosidase (β-d-glucoside glucohydrolase; EC 3.2.1.21) was extracted from coleoptiles of 15 maize genotypes (3 normals, 10 nulls, and 2 hybrids) in two fractions, the soluble and the insoluble. The enzyme activity was measured spectrophotometrically in the soluble fraction and also studied on zymograms after native gel electrophoresis and isoelectric focusing. The enzyme was purified from a normal genotype by anion-exchange chromatography and preparative electrophoresis. Antisera were raised in four rabbits, and the soluble and the insoluble extracts of each genotype were analyzed for a cross-reacting material by ELISA and immunoblotting. The results showed that extracts from both the normal and the null genotypes had β-glucosidase activity, and the activity measured spectrophotometrically was 2- to 10-fold higher in normals than in nulls. Zymograms of the null genotypes were devoid of distinct bands that were present in those of normals and hybrids from crosses between normals and nulls. Zymograms of both the normal and the null genotypes had a diffuse, smeared zone of activity at the cathodic end of native gels. A cross-reacting antigen was present in extracts of both genotypes when assayed by ELISA and a 60-kD polypeptide (β-glucosidase monomer) was detected by four different monospecific β-glucosidase antisera on Western blots by immunostaining. Moreover, six of seven null genotypes had a larger amount of their 60-kD polypeptide in the insoluble fraction than in the soluble fraction. These data show that both the null and the normal genotypes have similar amounts of the enzyme protein, but the enzyme occurs mostly as insoluble or poorly soluble polymers in nulls, and the monogenic inheritance reported for the null alleles of theglu locus is likely to be for a factor encoded by another locus which affects directly or indirectly the solubility of the enzyme by increasing its polymerization into large quaternary structures.
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    Astrophysics and space science 224 (1995), S. 81-84 
    ISSN: 1572-946X
    Keywords: Chemistry ; Depletions ; Shocks ; IRAS 05338-0624 ; NGC 1333 IRAS 4
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract High resolution interferometer and single-dish observations of young, deeply embedded stellar systems reveal a complex chemistry in the circumstellar environments of low to intermediate mass stars. Depletions of gas-phase molecules, grain mantle evaporation, and shock interactions actively drive chemical processes in different regions around young stars. We present results for two systems, IRAS 05338-0624 and NGC 1333 IRAS 4, to illustrate the behavior found and to examine the physical processes at work.
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    Astrophysics and space science 216 (1994), S. 153-154 
    ISSN: 1572-946X
    Keywords: Chemistry ; Molecular Hydrogen ; Cloud Models
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    Topics: Physics
    Notes: Abstract Observations of the CO J=1-0 line are commonly used as a tracer for molecular material in clouds. The ratio of the H2 column density to the integrated intensity of this line,X, is often taken to be constant, despite theoretical and observational uncertainty. We have tried to identify how this ratio depends on cloud parameters, testing a simple theoretical argument suggesting its invariance with respect to density. The apparent constancy can be understood if clouds are clumpy on scales of Av ≈ 1-2 mag.
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    Boundary layer meteorology 85 (1997), S. 197-222 
    ISSN: 1573-1472
    Keywords: Turbulence ; Chemistry ; Closure ; Convective boundary layer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract We study the interactions of chemistry and turbulent mixing of tracersin the convective boundary layer with a second-order closure model,including higher order chemistry terms. In order to limit the number of predictive equations we prescribe the profiles for ¯w¯Θ, ¯w¯θ ¯θ and the lengthscale l. However, for model validation we treat temperature and humidity asinert tracers, and compare the results with profiles observed during theAir Mass Transformation Experiment, and with similarity expressions for thesurface layer. We find good agreement of the mean profiles, but the (co-)variances are slightly underpredicted. Furthermore, the model usesdiagnostic equations expressing third moments of concentration in terms ofsecond moments and their vertical derivatives. They are compared withlarge-eddy model results, showing good agreement and, therefore, thesimplifications are justified. The model is applied to the transport of two gases subject to one bimolecular reaction. The importance of concentration correlations on themean transformation rate is studied. For two gases diffusing in oppositedirections we find for moderate and fast chemistry a 50% and90% decreased transformation rate due to the negatively correlatedconcentrations. These values are similar to large-eddy results of Schumannand Sykes et al. For two bottom-up tracers we find that the covariance ofboth reactive species is either positive or negative, increasing or reducingthe effective transformation rate depending on the Damköhler number (the ratio of the turbulent and the chemistry timescale). A significantdirect influence of chemistry on the flux divergence is found in bothcases. According to the model the effective transport to mid-levels of theboundary layer is increased when two reactive tracers diffuse in oppositedirections, and decreased in the case of two bottom-up tracers.
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    Journal of chemical ecology 23 (1997), S. 2695-2705 
    ISSN: 1573-1561
    Keywords: Defense ; herbivory ; aphids ; wheat ; Gramineae ; hydroxamic acids ; Defense theory ; Carbon/Nutrient theory
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Hydroxamic acids (Hx) are natural products of Gramineae that are associated with cereal resistance to pests. We aimed at characterizing the induction of Hx accumulation in seedlings of wheat,Triticum aestivum, by short-term infestation of the cereal aphid,Rhopalosiphum padi. A load of 25 aphids increased significantly the Hx levels in the infested primary leaf in comparison with control levels. Lower loads did not increase Hx concentration. Aphid infestation lasting 16 hr did not elicit induction of Hx, even after a time-lag of 32 hr to allow the expression of any induced response. Forty-eight hours was the minimum duration of aphid infestation required to trigger Hx induction. The age of the infested tissue (the primary leaf) did not affect induction. Similar increases of Hx were found in unfolding, expanding, and totally expanded primary leaves. It was determined that the regime of nutrient supply (N-intensive nutritive solutions at low and high concentration) to wheat seedlings had no effect on the magnitude of the aphid-induced Hx (N-based secondary metabolites). Results obtained are discussed in the framework of general theories of plant defense allocation.
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  • 44
    ISSN: 1573-3025
    Keywords: pollen ; Gramineae ; prevention ; phenology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Owing to the great pollen sensitivity of some allergic patients and without effective pollen forecasting, it is often difficult to set a preventive therapy of pollinosis. In 1987 and 1988 we compared the symptoms of 45 patients sensitive to grass pollen, daily pollen counts data recorded by a gravimetric and a volumetric sampler as well as meteorological data and observations of floral phenology. Symptoms appeared to be strictly correlated with peak periods of pollen dispersion, but we observed allergic symptoms in our patients long before atmospheric pollen was detected by the pollen traps. On the other hand, these early occurring symptoms seemed to be connected with the first Gramineae flowering.
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  • 45
    ISSN: 1573-3025
    Keywords: aerobiology ; epidemiology ; Gramineae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Epidemiological and aerobiological observations (1987;1989) have been carried out for three years in order to search the existing relationship between the Gramineae's daily pollen concentration in Palermo's atmosphere and the number of hay fever cases due to such pollen. The aerobiological data were obtained with a 2000 VPPS volumetric sampler. Clinical research was performed on 555 hay fever patients treated in our ambulatory over a three-year period (1987–1989). These data, elaborated by a seven day running mean method and correlated with epidemiological data, evidenced that three of the pollen families in our territory are clinically important: Urticaceae,Parietaria prevailing among them, Gramineae and Oleaceae,Olea europaea prevailing among them. The Gramineae are the second most important allergenic pollen (32,08% of all the pollinosis) whereas, as far as its concentration in the atmosphere is concerned; it ranks third followingParietaria and Oleaceae.
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  • 46
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    Biochemical genetics 28 (1990), S. 319-336 
    ISSN: 1573-4927
    Keywords: Zea mays ; Gramineae ; β-glucosidase ; null allelism ; immunoblotting ; electrophoresis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Maize β-glucosidase (β-d-glucoside glucohydrolase; EC 3.2.1.21) was extracted from coleoptiles of 15 maize genotypes (3 normals, 10 nulls, and 2 hybrids) in two fractions, the soluble and the insoluble. The enzyme activity was measured spectrophotometrically in the soluble fraction and also studied on zymograms after native gel electrophoresis and isoelectric focusing. The enzyme was purified from a normal genotype by anion-exchange chromatography and preparative electrophoresis. Antisera were raised in four rabbits, and the soluble and the insoluble extracts of each genotype were analyzed for a cross-reacting material by ELISA and immunoblotting. The results showed that extracts from both the normal and the null genotypes had β-glucosidase activity, and the activity measured spectrophotometrically was 2- to 10-fold higher in normals than in nulls. Zymograms of the null genotypes were devoid of distinct bands that were present in those of normals and hybrids from crosses between normals and nulls. Zymograms of both the normal and the null genotypes had a diffuse, smeared zone of activity at the cathodic end of native gels. A cross-reacting antigen was present in extracts of both genotypes when assayed by ELISA and a 60-kD polypeptide (β-glucosidase monomer) was detected by four different monospecific β-glucosidase antisera on Western blots by immunostaining. Moreover, six of seven null genotypes had a larger amount of their 60-kD polypeptide in the insoluble fraction than in the soluble fraction. These data show that both the null and the normal genotypes have similar amounts of the enzyme protein, but the enzyme occurs mostly as insoluble or poorly soluble polymers in nulls, and the monogenic inheritance reported for the null alleles of theglu locus is likely to be for a factor encoded by another locus which affects directly or indirectly the solubility of the enzyme by increasing its polymerization into large quaternary structures.
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  • 47
    ISSN: 1573-5028
    Keywords: Fusion protein ; geminivirus ; Gramineae ; single-stranded ; DNA virus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A polypeptide of approximately 11 000 daltons (11 kDa protein) encoded by an open reading frame (10.9 ORF) from the virion sense of maize streak virus (MSV) DNA has been detected among the products of in vitro translation reactions programmed with RNA from infected maize plants and also in total protein extracts from infected leaves. The 11 kDa protein has not been detected in virions and is therefore proposed to have a nonstructural role. Viral DNA with an additional in-frame translation stop codon in the 10.9 ORF was not infectious when transmitted to maize plants via Agrobacterium tumefaciens “agroinfection”, suggesting that the 10.9 ORF may be essential for virus function. Computer comparison data show that equivalent ORFs in wheat dwarf virus (WDV) and digitaria streak virus (DSV) have some sequences in common with the 10.9 ORF of MSV. Further-more, the absence of similar sequences in geminiviruses which infect dicotyledonous plants suggests that the 11 kDa protein and its putative homologs in WDV and DSV have a function necessary only for those geminiviruses which infect the Gramineae. The significance of the 11 kDa protein in relation to expression of the virion sense DNA of MSV is discussed.
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  • 48
    ISSN: 1573-5028
    Keywords: agroinfection ; Agrobacterium ; strains ; maize streak virus ; Gramineae ; maize
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Parameters affecting the efficiency of agroinfection of maize streak virus (MSV) in maize have been determined. Monomeric units, cloned at a number of sites in the MSV genome were not infectious but multimeric units containing partial duplications were equally as infectious as complete tandem dimeric clones. Inoculation of tandem dimeric units conjugated into different strains of Agrobacterium showed that both A. tumefaciens and A. rhizogenes were able to transfer DNA to maize and this ability was Ti (or Ri) plasmid-specific. Nopaline strains of A. tumefaciens and both agropine and mannopine A. rhizogenes strains efficiently transferred MSV DNA to maize. A number of strains were capable of MSV DNA transfer to other members of the Gramineae, providing information which may be essential for Agrobacterium-mediated transformation of monocotyledonous plants.
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  • 49
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    Plant molecular biology 23 (1993), S. 255-265 
    ISSN: 1573-5028
    Keywords: cDNA ; cold acclimation ; freezing tolerance ; Gramineae ; leaf ; light
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We report here the identification and characterization of a new leaf-specific light-stimulated gene induced during cold acclimation of wheat. Sequence analysis revealed that the gene encodes a protein of 19 kDa with a pI of 8.8. This is a novel protein with a particular charge distribution. The C-terminal half has a high propensity to form an α-helix and contains all the acidic amino acids with a net negative charge of -7. On the other hand, the N-terminal half is rich in proline, lysine and arginine with a net positive charge of +10. These properties are commonly found in several transcription factors. The protein is also rich in alanine (21%), is hydrophilic but not boiling soluble in contrast to other alanine-rich proteins. During low temperature exposure, the corresponding mRNA accumulates rapidly in the leaf and remains at a constant level in two tolerant cultivars used. However, is a less tolerant cultivar, the mRNA level declines despite maintaining the plants at 4°C. Southern blot analysis indicates that the differential expression in the less tolerant genotype is not due to a different genomic organization or gene copy number. The mRNA was specifically localized in leaf tissues and increased several-fold during the greening at 4°C. Furthermore, this gene is not induced in callus cultures acclimated in the absence or presence of light. This suggests that the full expression of this gene is dependent on organized leaf tissue. The expression of this gene was not affected by ABA, drought, heat shock, salinity, wounding or anaerobiosis, demonstrating that it is specifically induced by low temperature. The Wcs19 mRNA is preferentially expressed in tolerant Gramineae species.
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  • 50
    ISSN: 1573-5028
    Keywords: chloroplast-derived trnH ; chloroplast genome ; DNA transfer ; gene expression ; Gramineae ; mitochondrial genome
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We reported previously that the mitochondrial sequence that contains the chloroplast-derived trnH gene has been highly conserved in the region around one terminus of the junction between chloroplast-derived and mitochondrion-specific sequences in most of the gramineous plants analyzed [15]. The results of RT-PCR, northern hybridization, in vitro capping and ribonuclease protection experiments show that the chloroplast-derived trnH gene is transcribed from a putative promoter that is located in the mitochondrion-specific sequence. Gene expression in this region seems to be correlated with the conservation of the sequence at the junction between the chloroplast-derived fragment and the mitochondrion-specific sequence.
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  • 51
    ISSN: 1573-5028
    Keywords: hydroxyproline-rich glycoprotein ; sorghum ; Gramineae ; 3′ intron
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  • 52
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    Plant molecular biology 18 (1992), S. 617-619 
    ISSN: 1573-5028
    Keywords: rice ; hydroxyproline-rich glycoprotein ; Gramineae
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  • 53
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    Theoretical and applied genetics 86 (1993), S. 181-188 
    ISSN: 1432-2242
    Keywords: Sugarcane ; Gramineae ; Tissue culture ; RFLP ; Molecular analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The genomic stability of tissue culture regenerants of sugarcane (Saccharum spp. hybrids, cvs ‘CP721210’, ‘CP68-1067’ and ‘B43-62’) was analyzed by DNA restriction fragment length polymorphism (RFLP). Plants regenerated from calli, cell suspensions, cryopreserved cell suspensions and protoplasts were used. Total DNA isolated from 19 different sources was digested with EcoRI, HindIII, BamHI, BamHI, EcoRI and PstI and probed with six known maize mitochondrial genes (coxI, coxII, atpA, atp6, atp9 and rrn18-rrn5), three random maize mitochondrial cosmid clones, two random maize chloroplast cosmid clones and a wheat Nor locus clone. Hybridization patterns indicated that the variation observed was minor and appeared only in the secondcycle regenerants. No differences were observed among the three cultivars and the regenerants from calli, suspension culture, cryopreserved suspension culture and protoplasts. Mitochondrial DNA (mtDNA) isolated from ‘CP72-1210’ plants and its embryogenic cell suspensions, and bulk samples from all ‘CP72-1210’ regenerants pooled together were digested with EcoRI, HindIII, PstI, BamHI and SalI and probed with three recombinationally active wheat mtDNA clones, K′, K3 and X2. No variation in the mtDNA restriction patterns was observed between the ‘CP72-1210’ plants and its regenerants. However, restriction pattern variation was observed only from EcoRI digestion, and hybridization patterns of K3, K′ and X2 revealed minor variations in the mtDNA of cell suspensions when compared with the DNA of the ‘CP72-1210’ plant. Except for a qualitative variation detected by the X2 probe and minor stoichiometric variations detected by the K3 probe, sugarcane DNAs were found to be stable after plant regeneration.
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  • 54
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    Theoretical and applied genetics 91 (1995), S. 681-690 
    ISSN: 1432-2242
    Keywords: RFLP ; Barley ; Hordeum vulgare ssp. spontaneum ; Gramineae ; Comparative mapping
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Several gene linkage maps have been produced for cultivated barley. We have produced a new linkage map for barley, based on a cross between Hordeum vulgare subsp. spontaneum and Hordeum vulgare subsp. vulgare (Hvs x Hvv), having a higher level of polymorphism than most of the previous barley crosses used for RFLP mapping. Of 133 markers mapped in the Hvs x Hvv F2 population, 69 were previously mapped on other barley maps, and 26 were mapped in rice, maize, or wheat. Two known gene clones were mapped as well as two morphological markers. The distributions of previously mapped markers were compared with their respective barley maps to align the different maps into one consensus map. The distributions of common markers among barley, wheat, rice and maize were also compared, indicating colinear linkage groups among these species.
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  • 55
    ISSN: 1432-2242
    Keywords: Biomass ; Gramineae ; Genetic variability ; Hybrid triploid napiergrass ; Pennisetum ; Plant tissue culture ; Somatic embryogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Five hundred and twenty-four plants of a triploid, sexually sterile hybrid napiergrass (Pennisetum americanum x P. purpureum; 3x=21) were regenerated from embryogenic callus cultures obtained from segments of young inflorescences. Replicated field trials were conducted for two consecutive years to compare the biomass yield, phenotype and cytology of tissue culture regenerants (TC) and vegetatively propagated (V) plants. In the first year total biomass yield of TC plants was significantly greater than V plants but there was no significant difference in the second year. TC plants had more tillers compared to V plants. V plants did not show any morphological variability. The TC population also exhibited a high degree of phenotypic stability (96%). There were 23 phenotypic variants in the TC population of 524, most of them being more dwarf and late-flowering. Detailed morphological analysis of the TC-variant plants suggests that they very likely arose from only a few variant cell lines. Cytological analysis indicated stability of the triploid status in randomly selected regenerants. Two of the morphological variants were hexaploids (6x=42). It is concluded that embryogenic callus cultures can provide useful alternative for the rapid propagation of hybrid napier-grass which is commonly propagated by cuttings.
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  • 56
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    Theoretical and applied genetics 73 (1987), S. 551-555 
    ISSN: 1432-2242
    Keywords: Festuca pratensis Huds. ; Meadow fescue ; Gramineae ; Leaf senescence ; Mutation ; Chloroplast ; Phosphoglucoisomerase isoenzymes ; Membrane turnover
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A spontaneous mutation arising in Festuca pratensis has the effect of stabilizing the pigmentproteolipid complexes of thylakoid membranes so that leaf tissue does not turn yellow during senescence. Inheritance of the non-yellowing character was analysed in crosses between the wild-type cultivar Rossa and a mutant line Bf 993. Electrophoretic variants of cytoplasmic phosphoglucoisomerase coded by alleles of the nuclear gene Pgi-2 were used to identify hybrids during intercrossing. About 96% of the F1 progeny were heterozygous and all were phenotypically yellowing. In the F2 generation yellow ∶ green segregated in a ratio of 2.14∶1, not significantly different from 3∶1. In the backcross between F1 and Bf 993 the ratio was 1∶1 yellow ∶ green. There was no indication of linkage to Pgi-2. Senescence of detached Bf 993 and Rossa leaves was compared with that of the F1 hybrid. The hybrid behaved in an essentially identical fashion to the wildtype parent, and in marked contrast to the mutant, in all aspects of the senescence syndrome investigated, including loss of chlorophyll, carotenoids and the light-harvesting chlorophyll-protein of thylakoid membranes, and elevation of the particulate protein ∶ chlorophyll ratio in the terminal stages. It is concluded that there exists in Festuca pratensis a nuclear gene, designated Sid (senescence-induced degradation) which regulates turnover of hydrophobic components of photosynthetic membranes in ageing leaf tissue and which occurs in at least two allelic forms, y (yellow) dominant over g (green).
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  • 57
    ISSN: 1432-2242
    Keywords: Cereals ; Gramineae ; Somatic embryogenesis ; Triticum aestivum ; Wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Immature embryos, inflorescences, and anthers of eight commercial cultivars of Triticum aestivum (wheat) formed embryogenic callus on a variety of media. Immature embryos (1.0–1.5 mm long) were found to be most suitable for embryogenic callus formation while anthers responded poorly; inflorescences gave intermediate values. Immature embryos of various cultivars showed significant differences in callus formation in response to 11 of the 12 media tested. No significant differences were observed when the embryos were cultred under similar conditions on MS medium with twice the concentration of inorganic salts, supplemented with 2,4-D, casein hydrolysate and glutamine. Furthermore, with inflorescences also no significant differences were observed. Explants on callus formation media formed two types of embryogenic calli: an off-white, compact, and nodular callus and a white compact callus. Upon successive subcultures (approximately 5 months), the nodular embryogenic callus became more prominent and was identified as ‘aged callus’. The aged callus upon further subculture, formed an off-white, soft, and friable embryogenic callus. Both the aged and friable calli maintained their embryogenic capacity over many subculture passages (to date up to 19 months). All embryogenic calli (1 month old) from the different callus-forming media, irrespective of expiant source, formed only green shoots on regeneration media that developed to maturity in the greenhouse. There were no significant differences in the response of calli derived from embryos and inflorescences cultured on the different initiation media. Also, the shoot-forming capacity of the cultivars was not significantly different. Anther-derived calli formed the least shoots. Aged and friable calli on regeneration media also formed green shoots but at lower frequencies. Plants from long-term culture have also been grown to maturity in soil.
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  • 58
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    Theoretical and applied genetics 73 (1987), S. 793-798 
    ISSN: 1432-2242
    Keywords: Cereals ; Gramineae ; Maize ; Protoplasts ; Somatic embryogenesis ; Suspension culture ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Protoplasts isolated from a totipotent embryogenic cell suspension culture of Zea mays L. (cultivar ‘Dekalb XL82’) underwent sustained cell divisions when cultured in liquid as well as agarose media. Optimal colony formation (5%) occurred in a liquid medium containing 0.5 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D). A soft and unorganized callus was formed when the protocolonies were transferred to agar solidified suspension maintenance medium. Compact, organized and yellow to pale green folded structures and somatic embryos were formed upon subsequent transfer of this callus to a low 2,4-D medium. Clusters of somatic embryos germinated precociously but no plants were recovered.
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  • 59
    ISSN: 1432-2242
    Keywords: Gramineae ; Genetic analysis ; Pennisetum glaucum ; Somatic embryogenesis ; Tissue culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Genetic analysis was conducted on the qualitative and quantitative traits of sexual progeny derived from embryogenic cultures of two inbred lines of Pennisetum glaucum (L.) R. Br. (pearl millet). These lines included a genetically stable inbred of Tift 23 BE and a genetic marker line, derived from Tift 23BE, which bore qualitative genetic markers for a dominant purple plant trait (P) and two recessive traits, early flowering (e1) and yellow stripe (ys). Tissue culture regenerant populations (R0) and progeny populations (R1) produced from these plants by selfing showed no qualitative genetic variation when derived from the genetically stable inbred Tift 23BE. In contrast, stably inherited qualitative variation for a number of genetic markers was observed in R0, R1, and R2 progeny of the genetic marker line. In a population of 1,911 plants regenerated over a 12-month period, 0.02% of the population lost or showed reduced expression of the purple plant trait and 92% of plants were chlorophyll deficient. Plants showing reduction or loss of anthocyanin synthesis also flowered later. None of the purple plants showed any significant variation in flowering time. The incidence of chlorophyll deficiency increased with time in culture, 51 % of the progeny regenerated after 1 month were chlorophyll deficient, while 100% of the plants regnerated after 12 months were chlorophyll deficient. Qualitative variation was also observed in control populations of the genetic marker line where 1 plant in a total of 1,010 lacked purple pigmentation and a total of 6% showed chlorophyll variation in the first generation (S0). The presence of qualitative variation in controls suggests that the inherent variation present in the original explant was expressed and perpetuated in vitro. Quantitative variation was observed for a number of traits in the first sexual cycle (R1) of the marker line but did not occur in a subsequent generation, suggesting that this variation was epigenetic.
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  • 60
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    Theoretical and applied genetics 83 (1992), S. 947-955 
    ISSN: 1432-2242
    Keywords: Gramineae ; napier grass ; Somatic embryo genesis ; Variation ; Pennisetum purpureum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We have investigated the extent of biochemical and molecular variation in 63 plants of napier grass (Pennisetum purpureum K. Schum.) regenerated from 3- to 24-week-old embryogenic callus cultures. The calli were derived from cultured basal segments of young leaves and immature inflorescences obtained from a single fieldgrown donor plant. The entire population was analyzed for the activity of 14 isozyme systems, but no qualitative variation was found at any of the loci examined. Similarly, no restriction fragment length polymorphisms (RFLPs) were detected in the mitochondrial, plastid and nuclear genomes in a representative sample of regenerated plants. Our results confirm earlier reports of the genetic uniformity of plants derived from somatic embryos and highlight their value both for clonal propagation and for genetic transformation.
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  • 61
    ISSN: 1432-0878
    Keywords: Milk ; Fat globule membrane ; Carbohydrates ; Chemistry ; Ruthenium red ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fat globules of the cream fractions of human and rat milk were stained with ruthenium red. Under the electron microscope, discrete granules and an amorphous coat of lesser density are seen at the surface of the milk fat globules. Since ruthenium red binds anionic groups selectively, it is probable that the granules containe the greatest concentration of these groups. The cream fraction of rat milk contains hexoses, hexosamines, methylpentoses and sialic acid. Methylpentoses and hexosamines are significantly enriched in the cream fraction. It is concluded that the finding of a surface coat in milk fat globules is in keeping with the Bargmann-Knoop model and suggests a distinct mechanism for carrying certain complex carbohydrates in milk. The role of the negative charges at the outer surface of the membrane coat in maintaining fat globules in suspension and in binding certain cations such as calcium is suggested.
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  • 62
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    Plant systematics and evolution 169 (1990), S. 81-96 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Gramineae ; Festuceae ; Dactylis glomerata ; Enzymatic markers ; phenology ; interploid exchanges ; autopolyploidy ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Phylogenetic relationships between sympatric, morphologically indistinguishable diploid and tetraploid plants ofDactylis glomerata L. (Gramineae) in Galicia (Spain) were assessed using allozyme markers for 6 distinct systems. The study exploited recent introduction in Galicia and subsequent hybridization of an alien 4xDactylis subspecies possessing distinct allozymes from those of all the native plants. Opportunities for gene exchanges between the ploidies were estimated from in situ observations of flowering, examination of progenies in 2x/4x natural and experimental crosses, and enzyme analyses. Results show a high genetic similarity between the Galician diploids and tetraploids, which possess peculiar alleles in common. Although the ploidy levels usually have distinct flowering periods, interploidal crosses do occasionally occur. Gene flow is likely much more important from the diploid to the tetraploid level. A good genetic intermixing occurs between the Galician and the alien tetraploid entities which have simultaneous flowering. Autopolyploidization of the diploids followed by various rates of hybridization is proposed as one very probable origin of natural tetraploids inDactylis.
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  • 63
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    Plant systematics and evolution 178 (1991), S. 225-233 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Gramineae ; Eleusine ; DNA amount ; intra- and interspecific variation ; karyotypes ; hybridisation ; polyploidy ; domestication ; evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 2C nuclear DNA amounts were determined in 30 collections belonging to 10 species ofEleusine. About a 2.5-fold variation in genome size is evident in the genus. The 2C DNA amount in the diploid species ranged from 2.50 pg inE. verticillata to 3.35 pg inE. intermedia. In contrast, the tetraploid species showed a range from 4.95 pg inE. africana to 6.13 pg inE. floccifolia. At intraspecific level 10 collections ofE. coracana, 6 ofE. indica, 4 ofE. africana, 2 ofE. tristachya, and 2 ofE. kigeziensis did not show any significant variation. However, 2 collections ofE. floccifolia, connected with polyploidy, displayed about 90% variation. Polyploid species showed approximately double the genome size of that of their corresponding diploids. An evolutionary increase in DNA amount is evident inE. coracana during the course of its origin and domestication fromE. africana.
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  • 64
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    Plant systematics and evolution 207 (1997), S. 1-11 
    ISSN: 1615-6110
    Keywords: Gramineae ; Eleusine indica ; E. multiflora ; E. coracana subsp.coracana ; E. coracana subsp.africana ; E. tristachya ; C-value ; genome size ; nuclear DNA ; nuclei isolation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Interest in dinitroaniline herbicide resistant biotypes ofEleusine indica, and an as yet undetermined taxon ofEleusine, necessitated a revaluation of reported nuclear genome size estimates for available species in the genus. Laser flow cytometry showed that the nuclear DNA content of six of the seven species examined had 15 to 50% less DNA than reported previously. It was also determined that roots, as contrasted to leaves, possessed a large fraction of nuclei at the 4C or 8C DNA content level, in diploid or tetraploid species, respectively (i.e. the G2/M peak). Two major reasons for the previously reported overestimation may include sampling only of root tissues where endopolyploid and normal diploid nuclei both occur and the inappropriate choice of onion nuclei as an internal standard.
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  • 65
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    Molecular genetics and genomics 214 (1988), S. 6-10 
    ISSN: 1617-4623
    Keywords: Oryza sativa ; Gramineae ; Cell fusion ; Wild Oryza species
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Cell fusion was used to obtain hybrid plants of rice (Oryza sativa L.) and four wild Oryza species, O. officinalis, O. eichingeri, O. brachyantha, and O. perrieri, to incorporate useful traits of the latter species into rice. A total of 250 mature hybrid plants were obtained by electrofusion and nurse culture methods. The hybrid nature of these plants was confirmed by karyotypic, morphological, and isozyme analysis. The hybrids of O. sativa+O. eichingeri, O. sativa+O. officinalis and O. sativa+O. perrieri produced viable pollen and the O. sativa+O. eichingeri hybrid has produced a progeny plant. Our study demonstrates the use of cell fusion for future rice improvement.
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  • 66
    ISSN: 1617-4623
    Keywords: Cereals/grasses ; Gramineae ; Somatic hybridization ; Panicum maximum ; Pennisetum americanum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Protoplasts from Pennisetum americanum resistant to S-2-amino-ethyl-l-cysteine (AEC) were fused with protoplasts of Panicum maximum utilizing polyethylene glycol-dimethylsulfoxide after inactivation of the Pennisetum protoplasts with 1 mM iodoacetic acid. The iodoacetate treatment prevented division of Pennisetum protoplasts; therefore, only Panicum protoplasts and heterokaryons potentially could give rise to colonies. A second level of selection was imposed by plating 3–4-week-old colonies on AEC medium. Putative somatic hybrid calli were analyzed for alcohol dehydrogenase, 6-phosphogluconate dehydrogenase, aminopeptidase, and shikimate dehydrogenase isozymes. Three somatic hybrid cell lines (lines 2, 3, and 67) were identified which showed two bands of alcohol dehydrogenase activity representing homodimers of P. maximum and P. americanum as well as a novel intermediate band of activity where Panicum-Pennisetum heterodimers would be expected. Aminopeptidase and shikimate dehydrogenase were useful for identifying presumptive hybrid calli but the isozyme patterns were additive-evidence which would not preclude the selection of chimeric callus. A more complex isozyme pattern which varied among the somatic hybrids was observed for 6-phosphogluconate dehydrogenase. In the hybrid calli, the presence of DNA sequences homologous to both P. maximum and P. americanum sequences was confirmed by hybridization of a maize ribosomal DNA probe to XbaI and EcoRI restriction fragments. Growth of hybrid lines on various concentrations of AEC was either similar to the AEC-resistant parent (hybrid line 2) or intermediate between the resistant and sensitive parents (hybrid lines 3, 67).
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  • 67
    ISSN: 1617-4623
    Keywords: Oryza sativa ; Gramineae ; Cell fusion ; Protoplast ; Intertribal hybrid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Somatic hybridization of rice (Oryza sativa L.) and barnyard grass (Echinochloa oryzicola), a close relative of barnyard millet, was attempted using electrofusion and a new culture method developed for rice protoplasts (Kyozuka et al. 1987) to incorporate some of the agronomically important characters of the latter species into rice. Selection of hybrids was based on inactivation of rice protoplasts by iodoacetamide and the inability of barnyard grass protoplasts to divide. A total of 166 calli were identified as hybrids by isozyme and chromosome analyses. Hybrid calli were highly morphogenic, and 44 shoots were obtained. Most of them, however, were abnormal, and nine grew to plantlets whose morphology was distinct from that of either parent. Our study clearly demonstrates the totipotency of protoplasts in graminaceous monocots.
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  • 68
    ISSN: 1615-6110
    Keywords: Gramineae ; Poaceae ; Aegilops caudata var.caudata and var.polyathera ; Ae. comosa subsp.comosa var.thessalica ; subsp.heldreichii var.biaristata ; and var.subventricosa ; Esterase and peroxidase patterns ; phylogenetic relationships
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    Notes: Abstract The esterase and peroxidase patterns in five varieties ofAegilops caudata (genome type C) andAe. comosa (genome type M) were studied in order to elucidate the phylogenetic relationships within and between the two groups. The electrostarch gel electrophoresis technique was applied to extracts of shoot and root of 4-day-old seedlings, and the electropherograms were evaluated by gel densitometer traces. Inspite of considerable isozyme polymorphism, closer relationships in the banding patterns were found between different varieties of a single species than between varieties of the two different species. Esterase and peroxidase patterns of the twoAe. caudata varieties (caudata andpolyathera) are very similar and prove their close phylogenetic relationship. The isozyme affinities withinAe. comosa varieties are illustrated by the seriessubventricosa—biaristata—thessalica. The latter endemic variety has quite a number of characteristic bands and is relatively isolated. Altogether, the electrophoretic data agree well with morphological and cytological similarities (Zhukovsky 1928,Eig 1929,Karataglis 1973, 1975b).
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  • 69
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    Plant systematics and evolution 145 (1984), S. 15-28 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Poaceae ; Gramineae ; Hordeum spontaneum ; Wild gene pool ; factor analysis ; numerical taxonomy
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    Topics: Biology
    Notes: Abstract Samples from 11 populations of wild barley,Hordeum spontaneum, from Israel, were examined for morphological variation in a “common garden” plot design. Earliness traits had the highest between population variation of all traits studied. No relationship was found between dimensions of leaves and size of seeds.—Using numerical taxonomy methods, four races were found, which correspond to the geographical and environmental range of the species in Israel. It is concluded thatH. spontaneum shows a well developed tendency toward formation of highly adaptive races rather than exhibiting clinical variation.
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  • 70
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    Plant systematics and evolution 147 (1984), S. 1-27 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Poaceae ; Gramineae ; Dispersal ; hygroscopic movements ; trypanocarpy ; diaspore ecology ; cerrado vegetation ; Flora of Brazil
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    Topics: Biology
    Notes: Abstract 28 grass species from one hectare of cerrado vegetation in Botucatu, State of São Paulo, were studied with regard to the morphology and dispersal of their fruits. 13 species have dispersal units with smooth surfaces which are predominantly dispersed by big herbivorous mammals or birds which swallow them together with their food, e.g., during grazing (accidental endozoochory). On the other hand, smaller animals, including birds, also feed directly on the grains; some of them may escape trituration and digestion or may be even stored (synzoochory). 11 species are principally epizoochorous: 8 of these are ± exclusively adapted to epizoochory, adhering to the animals by scabrid awns or sharply pointed calli, while the rest behave as epizoochores and anemochores. 4 other species are predominantly anemochorous with their dispersal units bearing soft hairs, sometimes together with very small scabrid awns; in a wet state they also can adhere to animals (occasional epizoochory). Beside this, most grass fruits can behave as passive ballists, as passing animals, wind and rain may cause their dispersal units to fall to the ground (passive autochory). — Among the 28 species, 12 have dispersal units which are awned. In 7 of them the awns are spirally twisted; the base of the dispersal unit runs out into a sharply pointed callus and has harpoone-like hairs. These awns show hygroscopical movements which may lead to a drilling of the basal part of the dispersal unit into the sandy cerrado soil. This trypanocarpy is important for establishment but without function for dispersal.
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  • 71
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    Plant systematics and evolution 154 (1986), S. 251-257 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Gramineae ; Triticum ; Leaves ; tricin derivatives ; schaftoside ; iso-orientin O-glycosides ; chemosystematics ; origin of bread wheat
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    Topics: Biology
    Notes: Abstract Leaf flavonoids have been identified in seven species ofTriticum, all of which have been considered at one time as putative parents of the cultivated tetraploid and hexaploid wheats. The major constituents are apigenin- and luteolin-based glycosylflavones, some of which contain various O-glycosidic attachments at the 6″-position. Four tricin glycosides are present in minor amount, as is free tricin. The flavonoid patterns link togetherT. searsii, T. speltoides andT. squarrosa, on the one hand, andT. monococcum, T. boeoticum, T. thaoudar andT. urartu, on the other. These results indicate that the first three taxa are more likely to be diploid ancestors to the hexaploidT. aestivum than the latter four species.
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  • 72
    ISSN: 1615-6102
    Keywords: Pollen tube growth ; Microfibrillar pectins ; Dictyosome vesicles ; Gramineae ; Secale cereale ; Pennisetum typhoideum
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    Topics: Biology
    Notes: Summary Numerous polysaccharide-rich particles (“P-particles”) occur in the tip region of growing grass pollen tubes, where they apparently contribute to the extending wall. In other families the corresponding bodies have been shown to originate from dictyosome activity during pollen tube growth. However, in the grasses the main synthesis precedes anthesis; the P-particles represent up to 30% of the reserves of the vegetative cell of the dormant grain, numbering over one million in the pollen grain of rye. Their membranes are incomplete. The polysaccharide content, which is initially coarsely granular but becomes microfibrillar with hydration, is readily extracted with ammonium oxalate, and is probably pectic in nature. Simple methods for isolating the particles in relatively pure populations are described. Hydrolysis yields principally galactose, arabinose, glucose, and rhamnose. Apart from proteins derived from the original bounding membranes, a protein fraction is tenaciously bound to the polysaccharide. Isolated P-particles move anodically in an electrical field, and the possibility that their movement from the grain to the tube tip during growth depends on a potential gradient, already demonstrated for lily pollen tubes, is considered.
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  • 73
    ISSN: 1615-6102
    Keywords: A vena ; cytoskeleton ; Gramineae ; guard cell ; microtubule ; mitosis ; preprophase band ; stomatal complex
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    Topics: Biology
    Notes: Summary In order to study developmental changes in microtubule organization attending the formation of a longitudinally oriented preprophase band, the guard mother cells ofAvena were examined using a new procedure for anti-tubulin immunocytochemistry on large epidermal segments. We found that the interphase band (IMB) of transverse cortical microtubules present in these cells following asymmetric division is replaced after subsidiary cell formation by mesh-like to radial microtubules that extend throughout the cytoplasm. Many of the Mts are also grouped in bundles. Gradually, this intermediate array is succeeded by longitudinal elements of the PPB. Thus, preprophase band formation is accompanied by a 90° shift in Mt orientation, with a radial arrangement serving as an intermediate stage. The micrographs are most consistent with the rearrangement of intact Mts, although changes in Mt assembly are possible as well. The role of the IMB in guard mother cells is also discussed.
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  • 74
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    Protoplasma 167 (1992), S. 49-54 
    ISSN: 1615-6102
    Keywords: Avena sativa ; Cytokinesis ; Gramineae ; Mesophyll protoplast ; Mitosis ; Monocot
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    Topics: Biology
    Notes: Summary To date, oat (Avena sativa) is the only member of the Gramineae where protoplasts isolated from mesophyll are capable of divisions. A comparison of the events occurring in the first cell cycles between protoplasts isolated from differentiated tissues of grasses and dicotyledoneous plants is thus only possible using this species. The cytological analysis presented here shows that no fundamental differences exist, and that the transition from the differentiated state to a mitotically active cell parallels the events known from dicot protoplasts. Mitotic aberrations observed in oat protoplasts are similar to those known from other species, and cytokinesis is uncoupled from mitosis. Furthermore, the cell plate formation is often faulty. The high frequency of aberrations which are, separately regarded, not unusual, is a probable explanation for the early abortion of oat mesophyll protoplast-derived colonies.
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  • 75
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    Mycoscience 38 (1997), S. 281-286 
    ISSN: 1618-2545
    Keywords: Asclepiadaceae ; Gramineae ; Puccinia ; Umbelliferae ; Uredinales
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    Topics: Biology
    Notes: Abstract Puccinia erythropus, whose uredinial-telial stage occurs onMiscanthus andEularia spp. (Gramineae), was found to have a heteroecious macrocyclic life cycle with the spermogonial-aecial stage onCynanchum sublanceolatum var.obtusum (Asclepiadaceae).Puccinia miyoshiana, which forms the uredinial-telial stage onBothriochloa, Capillipedium, Eccoilopus, andSpodiopogon (Gramineae), is known to form its spermogonial-aecial stage onBuplerum spp. (Umbelliferae). By field observations and artificial inoculations,Bupleurum komarovianum was proved to serve as an additional spermgonial-aecial host of this fungus.
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  • 76
    ISSN: 1573-739X
    Keywords: Antimalarials ; Artemisia annua L ; Artemisinin ; Biosynthesis ; Chemistry ; Clinical trials ; Pharmacology ; Phytochemistry ; Sesquiterpenes ; Toxicology
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    Topics: Chemistry and Pharmacology
    Notes: Abstract Artemisinin, a sesquiterpene lactone endoperoxide isolated fromArtemisia annua L., and a number of its semisynthetic derivatives have shown to possess antimalarial properties. They are all eflective againstPlasmodium parasites that are resistant to the newest and commonly used antimalarial drugs. This article gives a survey of the literature dealing with artemisinin-relaled antimalarial issues that have appeared from the end of 1989 up to the beginning of 1994. A broad range of medical and pharmaceutical disciplines is covered, including phytochemical aspects like the selection of high-producing plants, analytical procedures, and plant biotechnology. Furthermore, the organic synthesis of artemisinin derivatives is discussed, as well as their mechanism of action and antimalarial activity, metabolism and pharmacokinetics, clinical studies, sideeffects and toxicology, and biological activities other than antimalarial activity.
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  • 77
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    Pharmacy world & science 10 (1988), S. 93-95 
    ISSN: 1573-739X
    Keywords: Anthracyclines ; Chemistry ; Drug stability ; Mitomycins
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    Topics: Chemistry and Pharmacology
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  • 78
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    Pharmacy world & science 10 (1988), S. 101-116 
    ISSN: 1573-739X
    Keywords: Chemistry ; Chromatography ; Etoposide ; Immunoassay ; Metabolism ; Podophyllotoxin ; Pharmacokinetics ; Teniposide
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    Topics: Chemistry and Pharmacology
    Notes: Abstract Etoposide (VP 16-213) and teniposide (VM 26) are semisynthetic epipodophyllotoxin derivatives active against a variety of tumours. The clinical efficacy has led to an increasing interest in these compounds. This review presents information on the mechanism of action, biochemical pharmacology, bioanalysis, metabolism and pharmacokinetics of etoposide and teniposide.
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  • 79
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    Pharmacy world & science 13 (1991), S. 109-118 
    ISSN: 1573-739X
    Keywords: Chemistry ; Consumer product safety ; Drug packaging ; Environmental pollution ; Plasticizers ; Polyvinyls
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    Topics: Chemistry and Pharmacology
    Notes: Abstract In this report the state of the art with respect to PVC as pharmaceutical packaging material is described. A general introduction into the applications of PVC is followed by a description of its production process. The metabolic effects of the monomer of PVC, vinyl chloride and of the most commonly used plasticizer diethylhexylphthalate are mentioned. Special attention is given to the pharmaceutical properties of plasticized PVC bags in comparison to other plastics and the environmental aspects of waste PVC disposal. Although there are emotional and political queries regarding the future use of PVC as a (pharmaceutical) packaging material, we conclude that there is no scientific justification for a total or partial ban of PVC. PVC will remain a fact of life as a cheap, versatile, high-performance and well-investigated plastic material for medical and pharmaceutical applications, to be replaced by newer plastics only for certain well-defined indications where the requirements of the plastic to be used are so specific that it will economically and technically be justified to use another polymer. Community and hospital pharmacists have to be prepared for a role in intake of waste plastic disposables, probably against deposit money, in order to fulfil the logistics needed for recycling.
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  • 80
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    Journal of science education and technology 5 (1996), S. 193-201 
    ISSN: 1573-1839
    Keywords: Chemistry ; chemistry education ; multiple intelligences ; imagery ; visual-spatial thinking
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    Topics: Natural Sciences in General , Technology
    Notes: Abstract Chemistry has evolved from a science dominated by mathematics into a science highly dependent on spatial-visual intelligence. Yet the chemical content of introductory courses remains taught essentially the same as 40–50 years ago. Chemistry, today, is recognized by chemists as the molecular science. Yet, school chemistry is alienated from that perception. Thanks to the computer, young people are more comfortable with visual imaging than their instructors were at the same age. Thus the time is rife to reinvigorate chemistry education by means of the visual-spatial approach, an approach wholly in conformance with the way modern chemistry is thought about and practiced.
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  • 81
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    Pharmacy world & science 8 (1986), S. 245-251 
    ISSN: 1573-739X
    Keywords: Analysis ; Antineoplastic agents ; Biosynthesis ; Botany ; Chemistry ; Cytotoxins ; Eupatorium cannabium ; Sesquiterpenes
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    Topics: Chemistry and Pharmacology
    Notes: Abstract A review onEupatorium cannabinum L. is given, including botany, history and constituents. The sesquiterpene lactones are discussed in more detail, covering their biosynthesis, isolation, analysis and biological activity. Special attention is paid to the cytotoxic and antitumour activities of the sesquiterpene lactones.
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  • 82
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    Pharmacy world & science 9 (1987), S. 305-314 
    ISSN: 1573-739X
    Keywords: Atrial natriuretic factor ; Blood pressure ; Chemistry ; Diuresis ; Homeostasis ; Kidney ; Muscle, smooth ; Natriuresis ; Receptors, endogenous compounds ; Renin-angiotensin system
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    Topics: Chemistry and Pharmacology
    Notes: Abstract It is now known that cardiac atria play an important role in blood pressure and volume regulation. Mechanical distension of the atria results in the release of a potent diuretic and natriuretic agent or agents termed the atrial natriuretic factor (ANF). Several structurally related forms of ANF exist in man and it is thought that these represent precursory forms of a single optimally active molecule and/or the presence of more than one form of active ANF. The chemical structure of ANF between different mammalian species is similar. ANF receptors have been identified in kidney, brain, vascular endothelial and smooth muscle cells, tracheal and bronchial smooth muscle and the adrenal glands of many mammalian species, including man. This would suggest that ANF influences blood pressure and volume homoeostasis by affecting any one of a number of biochemical or physiological mechanisms via different target tissues. ANF is now considered a potentially valuable therapeutic agent for the treatment of hypertension and congestive heart failure. Synthesis of potent receptor antagonists could be extremely useful in the treatment of various clinical situations which are produced or complicated by endogenously produced ANF, such as chronic orthostatic hypotension.
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    Chromosome research 4 (1996), S. 182-184 
    ISSN: 1573-6849
    Keywords: Gramineae ; primedin situ DNA labelling ; telomere ; Trifolium
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    Topics: Biology
    Notes: Abstract Primedin situ DNA labelling (PRINS) labels the telomeres ofAvena, Triticum, Secale, Hordeum, Lolium, Festuca andTrifolium when primers are used that correspond to the repeat unit ofArabidopsis telomeres. There are interstitial sites labelled in aLolium x Festuca hybrid.
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  • 84
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    Plant systematics and evolution 144 (1984), S. 119-135 
    ISSN: 1615-6110
    Keywords: Poaceae ; Gramineae ; Oryza perennis ; O. rufipogon ; Wild rice ; perennial-annual continuum ; water regime ; habitat disturbance ; companion species ; life-history traits ; intra-population differentiation
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    Topics: Biology
    Notes: Abstract Populations of the common wild rice of AsiaO. rufipogon Griff. (=Oryza perennis Moench) were studied with regard to interrelations between life-history traits and habitat conditions. They showed a perennial-annual continuum and differed in reproductive allocation and many other traits. Perennial populations were found in deep swamps, while annual populations were in shallower, temporary swamps which were parched in the dry season. The perennial and annual types tended to be in association with other perennial and annual plants, respectively, suggesting their niche differentiation. Intermediate perennial-annual populations were in communities with a high species diversity. In one population, plants growing on the periphery of the swamp were of annual and those in deeper center were of perennial type. Another population seemed to be differentiated into an annual and an intermediate type in accordance with different degrees of habitat disturbance. The small genetic distances found between the sub-populations suggested their differentiation within a gene pool.
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    Plant systematics and evolution 171 (1990), S. 1-14 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Compositae ; Chemistry ; systematics ; evolution
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    Topics: Biology
    Notes: Abstract The broad knowledge of the chemistry of theCompositae allows the discussion of its relevance for the systematics and evolution within the family. Furthermore a separation into subfamilies can be supported by the observed differences in the distribution of the main constituents in the tribes.
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  • 86
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    Plant systematics and evolution 179 (1992), S. 175-185 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Gramineae ; Deschampsia cespitosa ; Zinc tolerance ; heavy metal ; tolerant populations ; genetic basis ; heritability
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    Topics: Biology
    Notes: Abstract Patterns of zinc tolerance were examined in eightDeschampsia cespitosa (L.)Beauv. populations from normal and zinc-contaminated soils, using solution culture methods. Zinc-tolerant populations have evolved beneath pylons, and their tolerance patterns (degree, variance, heritability) vary. Tolerance is genetically based in all of them. In contrast to the cases of other species previously reported, some within-population differences are considerable, and may be due to both heterogeneity of the soils zinc contents, various gene combinations and gene recombinations between genotypes. One control population contains many tolerant plants, an original result which is discussed.
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  • 87
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    Plant systematics and evolution 193 (1994), S. 243-248 
    ISSN: 1615-6110
    Keywords: Gramineae ; Secale ; Air-dried chromosome preparation ; heterochromatin ; silver staining
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    Topics: Biology
    Notes: Abstract Air-dried chromosomes of rye when stained with aqueous silver nitrate show differential banding patterns. In addition to staining the NOR sites, the silver nitrate stains all regions of constitutive heterochromatin, as identified by Giemsa C-banding, as well as a number of small interstitial regions. However, the heterochromatin on the B chromosome is not stained by the silver method. This is proposed as a rapid and reliable banding method.
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  • 88
    ISSN: 1617-4623
    Keywords: Intergeneric somatic hybridization ; Gramineae ; Tall fescue (Festuca arundinacea) ; Italian ryegrass (Lolium multiflorum) ; Forage grasses
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Tall fescue (Festuca arundinacea Schreb.) protoplasts, inactivated by iodoacetamide, and non-morphogenic Italian ryegrass (Lolium multiflorum Lam.) protoplasts, both derived from suspension cultures, were electrofused and putative somatic hybrid plants were recovered. Two different genotypic fusion combinations were carried out and several green plants were regenerated in one of them. With respect to plant habitus, leaf and inflorescence morphology, the regenerants had phenotypes intermediate between those of the parents. Southern hybridization analysis using a rice ribosomal DNA probe revealed that the regenerants contained both tall fescue- and Italian ryegrass-specific-DNA fragments. A cloned Italian ryegrass-specific interspersed DNA probe hybridized to total genomic DNA from Italian ryegrass and from the green regenerated somatic hybrid plants but not to tall fescue. Chromosome counts and zymograms of leaf esterases suggested nuclear genome instability of the somatic hybrid plants analyzed. Four mitochondrial probes and one chloroplast DNA probe were used in Southern hybridization experiments to analyze the organellar composition of the somatic hybrids obtained. The somatic hybrid plants analyzed showed tall fescue, additive or novel mtDNA patterns when hybridized with different mitochondrial gene-specific probes, while corresponding analysis using a chloroplast gene-specific probe revealed in all cases the tall fescue hybridization profile. Independently regenerated F. arundinacea (+) L. multiflorum somatic hybrid plants were successfully transferred to soil and grown to maturity, representing the first flowering intergeneric somatic hybrids recovered in Gramineae.
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  • 89
    ISSN: 1615-6110
    Keywords: Gramineae ; Aveneae ; Deschampsia ; Aristavena ; Avenella ; Taxonomy ; molecular evolution ; karyotype ; C-banding ; isozymes ; seed proteins ; cpDNA
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    Topics: Biology
    Notes: Abstract We have analyzed the C-banding karyotypes, electrophoretic mobility of isozymes and seed proteins, total genomic DNA hybridization and chloroplast DNA ofAristavena setacea, Deschampsia cespitosa, D. media, Avenella flexuosa andA. stricta, which had been previously considered as belonging to the genusDeschampsia Beauv. s. l., in order to determine their taxonomic relationships. The results obtained with these different approaches indicate thatAvenella diverges substantially in all characters analyzed from the other two genera. No differences in six chloroplast DNA segments analyzed were found betweenAristavena andDeschampsia, which also show a level of total genomic DNA hybridization that indicates a relatively high proportion of common sequences. The closer relationship of these two genera contrasts with their divergence in karyotype structure that suggests a possible allopolyploid origin ofDeschampsia.
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    Molecular genetics and genomics 234 (1992), S. 43-48 
    ISSN: 1617-4623
    Keywords: Cold acclimation ; Molecular marker Antibody ; Freezing tolerance ; Gramineae
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    Topics: Biology
    Notes: Summary We isolated, and expressed in Escherichia coli, a gene (Wcs120) that is strongly induced during cold acclimation of wheat. The gene product was purified and used to produce antibodies. Immunoblotting experiments with the anti-WCS120 antibody identified several cold-induced proteins named FTMs for Freezing Tolerance Markers since they are associated with the development of freezing tolerance. This protein family was found to be coordinately regulated specifically by low temperature, highly hydrophilic, stable to boiling, and to have a pI above 6.5. The accumulation kinetics during the acclimation period indicated a positive correlation with the capacity of each genotype to develop freezing tolerance. Accumulation of the proteins was higher in the freezing-tolerant genotype than in the less tolerant one. In addition, their accumulation was more pronounced in the crown and leaf tissues compared with roots, confirming a relationship to the capacity of the different tissues to develop freezing tolerance. Analysis of different species (eight monocots and four dicots) indicated that this protein family is specific for freezing-tolerant cereals. The antibody did not cross-react with any of the non-cereal species examined. The anti-FTMs antibody represents a potential tool for breeders to select for freezing tolerance traits in the Gramineae.
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    Molecular genetics and genomics 206 (1987), S. 408-413 
    ISSN: 1617-4623
    Keywords: Gramineae ; Oryza sativa ; Protoplast ; Nurse culture ; Somatic embryogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Novel nurse culture methods have been developed for plant regeneration from protoplasts of rice (Oryza sativa). The nurse culture methods use the agarose-bead type culture in combination with actively growing nurse cells that are either in the liquid part of the culture or inside a culture plate insert placed in the centre of the dish. Protoplasts isolated from either primary seed calluses or suspension cultures of various callus origins, divided and formed colonies with a frequency of up to 10% depending on the protoplast source and the genotype. The presence of nurse cells was absolutely required for the induction of protoplast division. Plants were regenerated from protoplast-derived calluses of five tested cultivars with a frequency of 17%–50%. Close examination of the plant regeneration process suggested that plants are regenerated through somatic embryogenesis from protoplast-derived calluses. Over 300 protoplast-derived plants were transferred to either pots or the field and are being examined for karyotypic stability and various plant phenotypes.
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  • 92
    ISSN: 1573-5028
    Keywords: Gramineae ; mitochondrial recombination ; somatic hybrids
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    Topics: Biology
    Notes: Abstract Mitochondrial DNA (mtDNA) from cell suspension cultures of two intergeneric somatic hybrids of Pennisetum americanum (pearl millet) + Saccharum officinarum (sugarcane) was examined by restriction endonuclease digestion and hybridization with sorghum mtDNA cosmids. The mtDNA of one somatic hybrid was indistinguishable from that of pearl millet, while the second exhibited a combination of parental mtDNAs, suggesting mitochondrial fusion. Several novel, possibly recombinant, mtDNA restriction fragments were detected in this hybrid, which may have resulted from intergenmic recombination.
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    Plant and soil 104 (1987), S. 275-280 
    ISSN: 1573-5036
    Keywords: accumulation ; Cd ; Cruciferae ; Cucurbitaceae ; Gramineae ; Leguminosae ; NH4NO3-extractable Cd ; sand soil ; soil pH ; Solanaceae ; Taxonomy ; tolerance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Ten plant species belonging to 5 families,i.e., Cruciferae, Cucurbitaceae, Gramineae, Leguminosae, and Solanaceae, were grown in a sand soil at two pH levels. The soil was subjected to an application of CdCl2 at rates of 0 to 700 mgCd·kg−1 soil. The relationship between Cd concentration in the shoots (tc) and soil (sc; NH4NO3 extractable) was expressed by the equation: log (tc)=α+βlog (sc). The coefficients α and β were estimated for each species at each level of soil pH. Plottings of the scores on α and β axes showed that the Cd accumulation characteristics in the plants appeared to depend on the families irrespective of soil pH. Based on theupper critical concentration of Cd in the tops (Ct), the Cruciferae and Leguminosae species were found to be the most and the least tolerant to Cd, respectively. The Ct values correlated exceedingly well with the values of α.
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  • 94
    ISSN: 1573-5044
    Keywords: anther culture medium ; Gramineae ; heterosis ; Hordeum vulgare ; androgenic ability ; tissue culture competence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effects of an amino acid mixture and of plant growth regulators added to the FHG barley anther culture medium were examined using three barley cultivars (Cadette, Léger, and Igri) grown in two environments (growth cabinet and glasshouse). ‘Léger’ and ‘Igri’ were known as responsive, and ‘Cadette’ as recalcitrant to androgenesis. Our first experiment showed that the amino acid-supplemented medium was best for embryogenesis and regeneration of ‘Cadette’ and ‘Igri’ in both environments, and if ‘Léger’ in the growth cabinet. The addition of ABA and TDZ did not improve embryogenesis and plant regeneration, and PAA decreased them in the growth cabinet. The addition of the amino acid mixture in the FHG medium also reduced the percentage of albino plants in the growth cabinet, but growth regulators did not improve the percentage of albino plants, and in some cases increased it. In the growth cabinet, disregarding media, ‘Léger’ produced more embryos than ‘Cadette’ and ‘Igri’, and Léger' and ‘Igri’ produced more green plants than ‘Cadette‘. Percentages of albino plants were higher or ‘Cadette’ than for ‘Igri’ or ‘Léger’. In a second experiment, we compared seven hybrids with their parents for androgenic responsiveness. Hybrids had a higher ability to generate green plants than expected based upon the weighted average reflecting the contribution of each parent.
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  • 95
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    Plant and soil 155-156 (1993), S. 207-210 
    ISSN: 1573-5036
    Keywords: growth efficiency ; Gramineae ; Leguminosae ; respiration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract It has been generally considered that the low productivity of Leguminosae is caused by accumulation in the reproductive organs of a large amount of protein and lipid, since the biochemical costs of synthesizing these compounds is higher than that for carbohydrate. However, we report here on results which show that: the growth efficiencies (dry matter accumulated/ (dry matter accumulated + respiration)) of reproductive organs of Gramineae and Leguminosae were similar; the growth efficiency of rice in the vegetative stage was greater than that of soybean and field bean, regardless of nitrogen application rate; and when 14CO2, 14C-sucrose or 14C-asparagine were introduced to the leaf at the maturation stage, respiratory loss of the introduced 14C was greater in soybean and field bean, especially in the light, than in rice. Thus, it is assumed that the low productivity in Leguminosae is caused by a larger respiratory loss under both dark and light condition in the shoot, and not in the reproductive organs.
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  • 96
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    Plant and soil 130 (1991), S. 127-134 
    ISSN: 1573-5036
    Keywords: copper ; Gramineae ; iron ; micronutrients ; microorganisms ; phytosiderophores ; rhizosphere ; Strategy II ; uptake ; zinc
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Phytosiderophores (PS) are released in graminaceous species (Gramineae) under iron (Fe) and zinc (Zn) deficiency stress and are of great ecological significance for acquisition of Fe and presumably also of Zn. The potential for release of PS is much higher than reported up to now. Rapid microbial degradation during PS collection from nutrient solution-grown plants is the main cause of this underestimation. Due to spatial separation of PS release and microbial activity in the rhizosphere a much slower degradation of PS can be assumed in soil-grown plants. Concentrations of PS up to molar levels have been calculated under non-sterile conditions in the rhizosphere of Fe-deficient barley plants. Besides Fe, PS mobilize also Zn, Mn and Cu. Despite this unspecific mobilization, PS mobilize appreciable amounts of Fe in calcareous soils and are of significance for chlorosis resistance of graminaceous species. In most species the rate of PS release is high enough to satisfy the Fe demand for optimal growth on calcareous soils. In contrast to the chelates ZnPS and MnPS, FePS are preferentially taken up in comparison with other soluble Fe compounds. In addition, the specific uptake system for FePS (translocator) is regulated exclusively by the Fe nutritional status. Therefore, it seems appropriate to retain the term phytosiderophore instead of phytochelate.
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  • 97
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    Plant growth regulation 3 (1985), S. 269-275 
    ISSN: 1573-5087
    Keywords: Avena sativa ; Gramineae ; oats ; polyamine oxidase ; aminopropylpyrroline ; diaminopropane ; guazatine ; hydrogen peroxide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract In a homologous series of di-guanidines (NH2C(−NH)NH(CH2)xNHC(−NH) NH2) where x=2−12, greatest inhibition of polyamine oxidase was found with x=8. The synthetic fungicide guazatine 269-1 was particularly effective as an inhibitor of polyamine oxidase, with Ki of ca 10-8 M. Inhibition due to the tri-amine derived from guazatine by hydrolysis was less effective by a factor of ca 200. Comparison of various inorganic salts at 1 M showed that polyamine oxidase activity was enhanced in the order RbCl〉KCl〉KBr〉NH4Cl〉NaNO3〉LiCl〉LiCl=NaCl〉 control (no salt) 〉CaCl2=MgCl2. Activity in RbCl was about 4 to 5 times greater than in the salt-free control. Enzyme activity is rapidly lost during assay. This loss of activity could not be attributed to inhibition by aminopropylpyrroline or diaminopropane. Moreover the superoxide scavenger copper salicylate had no protective effect on enzyme activity.
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  • 98
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    Plant growth regulation 12 (1993), S. 91-98 
    ISSN: 1573-5087
    Keywords: gibberellins ; uccurrence ; glucose conjugates ; Gramineae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Data on the occurrence of free and conjugated gibberellins in different tribes of Gramineae are compiled and discussed with regard to their biosynthetic pathways. From the gibberellins detected so far the functioning of both the early 13-hydroxylation and the non-3,13-hydroxylation pathway of GA biosynthesis in gramineous plants can be deduced and the discovery of further gibberellin conjugates may be expected.
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  • 99
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    Genetic resources and crop evolution 41 (1994), S. 123-124 
    ISSN: 1573-5109
    Keywords: syteny ; homologous series ; variation ; Solanaceae ; Gramineae ; Vavilov
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Synteny, the co-linear arrangement of genes in related taxa, shows parallelity to Vavilov's law of homologous series and possibly provides a molecular approach for the explanation of this law.
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  • 100
    Electronic Resource
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    Plant cell, tissue and organ culture 10 (1987), S. 73-77 
    ISSN: 1573-5044
    Keywords: embryogenesis ; Phyllostachys viridis ; Gramineae ; micropropagation ; bamboo
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Leaf explants of Phyllostachys viridis (Young) McClure were cultured on Murashige and Skoog medium supplemented with 9×10-6 M 2,4-dichlorophenoxyacetic acid. Numerous embryoids were observed. On transfer to Murashige and Skoog medium lacking hormones, plantlets developed within two weeks and were later successfully transferred to the field.
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