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  • tissue culture  (37)
  • β-glucuronidase
  • Springer  (50)
  • American Meteorological Society
  • Cambridge University Press
  • 1995-1999
  • 1990-1994  (44)
  • 1955-1959  (6)
  • 1990  (44)
  • 1966
  • 1955  (6)
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  • Springer  (50)
  • American Meteorological Society
  • Cambridge University Press
  • Wiley-Blackwell  (3)
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  • 1995-1999
  • 1990-1994  (44)
  • 1955-1959  (6)
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  • 1
    ISSN: 1432-203X
    Schlagwort(e): African wild rice ; Oryza longistaminata plant regeneration ; tissue culture ; cell suspension ; histology
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Plant regeneration from 2-month-old callus cultures derived from immature leaves of 7-day-old aseptic seedlings and mature embryos of the African wild rice Oryza longistaminata was achieved at 20% and 100% frequency, respectively. The morphogenic potential of the embryo-derived calluses dropped from 100% at the third subculture to 12.5 % at the 12th subculture. Five-month-old morphogenic calluses were used to establish a fast-growing suspension culture which, when plated onto semisolid medium, still retained its ability to regenerate plantlets 9 months after initiation. Histological analyses demonstrated that late plant regeneration from established callus and suspension cultures occured through organogenesis, although some embryogenesis events may have taken place during initiation of these cultures.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Molecular and cellular biochemistry 94 (1990), S. 1-8 
    ISSN: 1573-4919
    Schlagwort(e): oxygen free radicals ; xanthine ; xanthine oxidase ; lysosomes ; β-glucuronidase ; hypoxia ; pH
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie , Medizin
    Notizen: Summary We investigated the effect of acidic environment, hypoxia and oxygen free radicals on the release of β-glucuronidase from rat liver lysosomes. A lysosomal enriched fraction from the homogenate of rat liver was prepared, using differential centrifugation technique. Exogenous oxygen free radicals were generated using xanthine-xanthine oxidase system. The release of β-glucuronidase activity was measured from the lysosomes. The lysosomal fraction was exposed to various pH (8.0, 7.4, 6.5, 6.0, 5.5) and pO2 (454, 172, 96, 57, 34 mm Hg) separately or to a combination of low pH (5.5, 6.5) and low PO2 (34, 57 mm Hg). The changes in pH or PO2 separately did not cause any increase in the release of β-glucuronidase activity. The presence of oxygen free radicals at each pH or PO2 resulted in about a 3-fold increase in the release of β-glucuronidase. A combination of very low PO2 and pH (PO2 (mm Hg)/pH; 34/5.5, 34/6.5) resulted in an increased release of β-glucuronidase from lysosomes. Oxygen free radicals in the presence of both low PO2 and pH resulted in a further increase in the release of β-glucuronidase. These data indicate that oxygen free radicals and not the alterations in pH and/or PO2 are primarily responsible for the disruption of lysosomes.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 3
    ISSN: 1573-5028
    Schlagwort(e): patatin ; potato ; transposon ; gene inactivation ; β-glucuronidase
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The promoter of the PGT3 patatin gene belonging to the class II subfamily is highly homologous to other class II patatin genes except for a 736 bp insertion in front of the putative transcription start site. The insertion is characterized by structural features resembling a transposable element such as an 11 bp inverted repeat at the termini and an 8 bp duplication flanking the insertion site. Despite the high homology to active patatin genes, fusion of its promoter to the β-glucuronidase reporter gene does not lead to detectable β-glucuronidase (GUS) activity in transgenic potato or tobacco plants, suggesting that the inactivation of this gene might be caused by the insertion of the transposon like element.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 4
    ISSN: 1573-5028
    Schlagwort(e): double promoter ; β-glucuronidase ; cell type specificity ; gene regulation ; seed storage protein gene
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The activity, tissue specificity and temporal expression of the tandem promoter region preceding a maize zein gene (zE19, encoding a 19 kDa zein protein) were tested in transgenic Petunia plants. To simplify the analysis, the tandem promoter as well as each of the two separate promoter regions were fused to the β-glucuronidase (GUS) reporter gene. All of the three constructs directed the synthesis of GUS in the endosperm of transformed seeds indicating that both separate promoters are independently activated and show the same tissue and cell type specificity observed for zein genes in maize. The kinetics of accumulation and the localization of GUS activity are not coordinated with those of Petunia endogenous seed storage proteins during the development of transformed seeds. Unexpectedly, we detected high levels of GUS activity in anthers of transformed Petunia plants for all three constructs. This appears to reflect the expression pattern of zein genes in maize, since we detect zein transcripts in anthers. Finally, we discuss the possible origin and function of the tandem promoter arrangement on the basis of these data.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    Springer
    Plant molecular biology 15 (1990), S. 527-538 
    ISSN: 1573-5028
    Schlagwort(e): β-glucuronidase ; CaMV 35S promoter ; genetic engineering ; immunohistochemistry ; Oryza sativa ; transgenic rice
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The cauliflower mosaic virus promoter is commonly used to drive transcription of chimeric genes in transgenic plants, including the cereals. To determine the tissue and cell types of cereal plants that the promoter functions in, transgenic rice plants containing a CaMV 35S promoter/GUS chimeric gene were analyzed for GUS activity. Insertion of a 35S/GUS chimeric gene at low copy number into chromosomal DNA of plants regenerated from electroporated protoplasts was confirmed by gel blot hybridization analysis of uncut and endonuclease-digested DNA. Quantitative measurement showed that GUS activity was some tenfold higher in rice leaves than in tobacco leaves [8] whereas activities obtained for rice roots were similar to those reported for tobacco roots. Histochemical localization of GUS activity confirmed that the CaMV 35S promoter functions in cells of the leaf epidermis, mesophyll and vascular bundle. It is also active in the cortex and vascular cylinder of the root, but only marginally active in the root epidermis. The generally similar distribution and levels of GUS activity obtained in differentiated tissue of stably transformed rice plants indicates the value of the CaMV 35S promoter as a positive control for studies in gene activity in transgenic monocots and dicots.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 6
    Digitale Medien
    Digitale Medien
    Springer
    Plant molecular biology 15 (1990), S. 821-825 
    ISSN: 1573-5028
    Schlagwort(e): β-glucuronidase ; glycosylation ; protein targeting ; reporter gene ; site-directed mutagenesis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract It has been documented that when furnished with an endomembrane signal sequence for the endoplasmic reticulum, β-glucuronidase (GUS) is N-glycosylated, resulting in the nearly complete loss of enzymatic activity. To enable use of β-glucuronidase as a reporter protein in secretory and vacuolar targeting studies, one of the two putative N-linked glycosylation sites within the GUS gene was altered by site-directed mutagenesis. The second N-linked glycosylation site was not altered because sequence analysis of nucleotide sequences around the second putative glycosylation site revealed that the published sequence was incorrect, and that no such site existed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 7
    Digitale Medien
    Digitale Medien
    Springer
    Plant molecular biology 15 (1990), S. 809-819 
    ISSN: 1573-5028
    Schlagwort(e): biolistic transformation ; β-glucuronidase ; microprojectiles ; tobacco chloroplast
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract We report here an efficient and highly reproducible delivery system, using an improved biolistic transformation device, that facilitates transient expression of β-glucuronidase (GUS) in chloroplasts of cultured tobacco suspension cells. Cultured tobacco cells collected on filter papers were bombarded with tungsten particles coated with pUC118 or pBI101.3 (negative controls), pBI505 (positive nuclear control) or a chloroplast expression vector (pHD203-GUS), and were assayed for GUS activity. No GUS activity was detected in cells bombarded with pUC118 or pBI101.3. Cells bombarded with pBI505 showed high levels of expression with blue color being distributed evenly throughout the whole cytosol of the transformants. pHD203-GUS was expressed exclusively in chloroplasts. We base this conclusion on: i) the procaryotic nature of the promoter used in the chloroplast expression vector; ii) delayed GUS staining; iii) localization of blue color within subcellular compartments corresponding to plastids in both shape and size; and iv) confirmation of organelle-specific expression of pHD203-GUS using PEG-mediated protoplast transformation. Chloroplast transformation efficiencies increased dramatically (about 200-fold) using an improved helium-driven biolistic device, as compared to the more commonly used gun powder charge-driven device. Using GUS as a reporter gene and the improved biolistic device, optimal bombardment conditions were established, consistently producing several hundred transient chloroplast transformants per Petri plate. Chloroplast transformation efficiency was found to be increased further (20-fold) with supplemental osmoticum (0.55 M sorbitol and 0.55 M mannitol) in the bombardment and incubation medium. This system provides a highly effective mechanism for introducing and expressing plasmid DNA within higher-plant chloroplasts, and the fact that GUS functions as an effective marker gene now makes many genetic studies possible which were not possible before.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 8
    Digitale Medien
    Digitale Medien
    Springer
    Plant molecular biology 14 (1990), S. 995-1006 
    ISSN: 1573-5028
    Schlagwort(e): patatin ; β-glucuronidase ; tuber formation ; sucrose ; transgenic potatoes
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Patatin is an abundant glycoprotein in the tubers of potato plants that has a lipid acyl hydrolase activity. Fusions of the promoter of patatin genes that are highly expressed in tubers with the reporter gene encoding β-glucuronidase (GUS) have shown that patatin transcription has a high degree of tuber specificity. Patatin transcription was also inducible in other organs of transgenic potato by growth on high concentrations of sucrose. Experiments were conducted to define regions of the patatin promoter that confered tuber specific expression and sucrose inducibility. Sequences between -40 and -400 bp and between -400 and -957 bp of the transcriptional start site were able to confer tuber-specific expression on a heterologous truncated promoter. The cell specificity of GUS transcription in the transformants indicated that organ specificity was possibly determined by source-sink relationships of sucrose, or a metabolite of sucrose, in the whole plant.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 9
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell reports 9 (1990), S. 419-423 
    ISSN: 1432-203X
    Schlagwort(e): Cell suspension ; cryopreservation, Gramineae ; Saccharum ; sugarcane ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Efficient plant regeneration was obtained from a cryopreserved embryogenic cell suspension of sugarcane established from leaf derived callus. Pregrowing the cells for three days in MS basal medium supplemented with 0.33 M sorbitol was essential to the process. The cells were cooled at a rate of 0.5°C/min to −40°C and then stored in liquid nitrogen. Thawing was carried out rapidly in water at +40°C, and the cells were then plated without washing onto filter paper discs placed on a semi-solid regeneration medium (MS basal + 3% sucrose + 0.13 mg/1 2,4-D +0.25 mg/1 BAP + 0.25 mg/1 kinetin + 0.25 mg/1 zeatin). The filter paper discs, along with the cells, were transferred to the same, fresh medium after five hours. After 24 hours the cells were scraped off, placed on fresh semi-solid medium and incubated at 28°C in the dark for two weeks before transfer to light. A regeneration efficiency of 92% was obtained (regenerated plants, expressed as a percent of unfrozen control). Plants regenerated from cryopreserved cells, and grown to maturity in the greenhouse, were morphologically identical to regenerated control plants.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 10
    Digitale Medien
    Digitale Medien
    Springer
    Journal of applied phycology 2 (1990), S. 137-143 
    ISSN: 1573-5176
    Schlagwort(e): carbon-source ; glycerol ; Grateloupia doryphora ; morphogenesis ; osmolality ; solidity ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Explants of Grateloupia doryphora were cultivated in Provasoli Enriched Seawater culture medium (PES) supplemented with glycerol (0.1, 0.3, 0.5 or 0.8 mol 1−1) or carbohydrates (0.1 or 0.3 mol 1−1 mannose, glucose and galactose) and agar (3, 8, 15 g 1−1 ). The osmolality of the medium was adjusted by dilution of the seawater (70 or 100%, v/v). The increase in fresh weight of explants cultivated in liquid medium with glycerol (0.3 mol 1−1) and without glycerol was compared. All experiments were carried out in the light, except for one assay in which the explants were cultivated in the dark. Glycerol was an effective carbon source for the vegetative propagation of G. doryphora in solid and liquid media. Mannose, glucose and galactose all had no effect on growth or morphogenesis of the explants. In solid media the main effect of glycerol was as a morphogenetic inductor, with PES70 (70% seawater) + 0.1 or 0.3 mol 1−1 glycerol + 3 or 8 g 1−1 agar the best formulation. An increase in the concentration of agar in glycerol-containing medium reduced the morphogenetic capacity of the explants, which developed into compact cell masses. The effects of glycerol were observed only in explants cultivated under light.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 11
    ISSN: 1617-4623
    Schlagwort(e): Agrobacterium tumefaciens ; β-glucuronidase ; Portable intron ; Splicing ; Transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Agrobacterium tumefaciens is a commonly used tool for transforming dicotyledonous plants. The underlying mechanism of transformation however is not very well understood. One problem complicating the analysis of this mechanism is the fact that most indicator genes are already active in Agrobacterium, thereby preventing the precise determination of timing and localisation of T-DNA transfer to plant cells. In order to overcome this obstacle a modified prokaryotic indicator gene was constructed. The expression of this indicator gene and its use in analysing early events in Agrobacterium-mediated plant transformation are described. A portable intron, derived from a plant intron, was introduced into the β-glucuronidase (GUS) gene. In transgenic plants containing this chimaeric gene the intron is spliced efficiently, giving rise to GUS enzymatic activity. Mapping of the splice junction indicates the exact removal of the intron. No GUS activity is detected in agrobacteria containing this construct due to the lack of a eukaryotic splicing apparatus in prokaryotes. Early phases after transformation of Arabidopsis cotyledon explants were analysed using this GUS-intron chimaeric gene showing that as early as 36 h after Agrobacterium infection significant GUS activity is detected. In vivo GUS staining of transformed cells clearly shows that quickly proliferating calli expressing GUS activity are formed, mainly at the cut surface. Minor transformation events occur however throughout the whole cotyledon. These data indicate that Agrobacterium-mediated T-DNA transfer to plants is much more efficient than has been judged from experiments where selection is applied immediately. The intron-containing GUS gene can be used as an optimised marker gene in transient and stable transformation experiments.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 12
    ISSN: 1617-4623
    Schlagwort(e): β-glucuronidase ; Hairy root ; Phytohormones ; T-DNA ; Rhizogenesis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The regulation in tobacco of the rolB and rolC promoters of Agrobacterium rhizogenes pRi 1855 TL-DNA was studied by using the β-glucuronidase (GUS) reporter system in transgenic plants. A 20- to 100-fold increase of GUS activity was selectively induced by auxin in rolB-GUS transformed mesophyll protoplasts, whereas this auxin-dependent increase was only 5-fold in rolC-GUS protoplasts. Moreover, both gene fusions exhibited similar tissue-specific expression in aerial parts but different patterns in roots. The spatial pattern of rolBGUS expression could be strongly modified by the addition of exogenous auxin, further suggesting that auxin plays a central role in the regulation of the rolB promoter in tobacco. The tissue-specific and auxin-dependent regulation of the rolB promoter is discussed in relation to the effects of the rolB gene on rhizogenesis and on cellular responses to auxin.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 13
    Digitale Medien
    Digitale Medien
    Springer
    Molecular genetics and genomics 223 (1990), S. 169-179 
    ISSN: 1617-4623
    Schlagwort(e): Enhancers ; Developmental regulation ; Library transformation ; T-DNA ; β-glucuronidase
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary In this paper we report on the use of a bidirectional enhancer cloning vehicle to isolate and characterize new enhancer sequences from Arabidopsis thaliana. A library of A. thaliana genomic Sau3A segments was constructed in Escherichia coli in the binary plasmid enhancer cloning vehicle pROA97. The T-DNA based vector carries abbreviated TATA regions from the cauliflower mosaic virus 35S transcription unit upstream of two genes. The library was transferred via triparental mating into Agrobacterium tumefaciens. The neomycin phosphotransferase II gene was used for selection of kanamycin-resistant transformed tobacco callus cells. Approximately 1100 transgenic plants were regenerated and assayed for expression of the E. coli β-glucuronidase (GUS) gene in leaves, stems, roots, or seeds. Plasmids carrying putative enhancer sequences were rescued from the genomes of transgenic plants and the cloned sequences were assayed for enhancer function in genetic selection experiments. Plants were regenerated from the kanamycin-resistant calli obtained in the secondary transformation experiments. Histochemical analysis of GUS activity in the leaf, stem, and root tissues of transgenic plants showed a variety of expression patterns. The DNA sequences are presented of five Arabidopsis segments which confer enhancer function.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 14
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 51 (1990), S. 249-256 
    ISSN: 1573-5060
    Schlagwort(e): Festuca arundinacea ; tall fescue ; chromosome pairing ; electrophoresis ; isoenzyme ; meiotic analyses ; somaclonal variation ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary This study was conducted using the isozymes ACP-1, ADH-1, GOT-2, GOT-3, MDH, 6-PGD-1 and PGI-2 to: a) compare isozyme banding patterns of tall fescue somaclones with parents and b) correlate tissue culture-induced chromosome abnormalities with variant banding patterns. The 174 somaclones were grouped into seven categories based on their meiotic analyses and time of regeneration from culture. Differences in isozyme frequency between categories compared by chi-square tests were greatest for MDH, 6-PGD-1 and PGI-2, and least for ACP-1. The most significant differences in frequency were found between somaclones and parents. In comparisons of somaclone categories, the most different isozyme distributions were between the early vs. late regenerated somaclones. No significant differences in isozyme frequencies were found between all 42-chromosome somaclones vs. aneuploid somaclones and the three somaclone groups (42-normal, 42-abnormal, aneuploid) compared to each other. This study suggests that culture-induced isozyme variation alters the distribution of the isozyme phenotypes, but is not directly correlated with chromosome abnormalities.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 15
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 85 (1955), S. 97-100 
    ISSN: 1573-5060
    Schlagwort(e): Agrobacterium ; transformation ; lily ; β-glucuronidase
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Lily cv. Harmony was inoculated with several Agrobacterium strains to study its susceptibility to Agrobacterium infection and transformation. Tumorous tissue formation on inoculated stem internodes of sterile-grown plantlets, as well as expression of a β-glucuronidase marker gene interrupted by an intron in cells of inoculated stem nodes, indicate that the monocotyledon Lilium is a host for Agrobacterium.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 16
    ISSN: 1573-5060
    Schlagwort(e): microprotoplast fusion ; partial genome transfer ; monosomic additions ; kanamycin resistance ; β-glucuronidase ; gene expression ; potato
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Various aspects of a microprotoplast fusion technique and the strategies followed for intergeneric partial genome transfer (one or a few chromosomes) and alien genes from sexually-incongruent donor species to recipient species are described. The essential requirements of the microprotoplast fusion technique are the induction of micronuclei at high frequencies, as well as the isolation and enrichment of sub-diploid microprotoplasts in donor species, efficient fusion of the donor microprotoplasts with normal recipient protoplasts and stable regeneration of plants from fusion products. The results on the production of microprotoplast hybrid plants between the transformed donor lines of Solanum tuberosum and Nicotiana Plumbaginifolia carrying various genetic markers, and a recipient line of Lycopersicon peruvianum or Nicotiana tabacum, and on the transfer and expression of alien genes (kanamycin resistance, β-glucuronidase) are presented. The data obtained on microprotoplast hybrid plants between S. tuberosum and L. peruvianum showed that many of the hybrids contained one potato chromosome carrying nptII and GUS, and 24 or 48 L. peruvianum chromosomes (monosomic additions), and that they were male-and female-fertile. Various applications of chromosome transfer by this technique, especially for economically-important traits (e.g. disease or stress resistance) from sexually-incompatible wild species, for construction of chromosome-specific DNA libraries through microdissection and microcloning of chromosomes, or by flow-sorting of chromosomes for genome analysis, are discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 17
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 85 (1955), S. 295-302 
    ISSN: 1573-5060
    Schlagwort(e): tissue culture ; somaclonal variation ; plant breeding
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Somaclonal variation is a tool that can be used by plant breeders. The review examines where this tool can be applied most effectively and the factors that limit or improve its chances of success. The main factors that influence the variation generated from tissue culture are (1) the degree of departure from organised growth, (2) the genotype, (3) growth regulators and (4) tissue source. Despite an increasing understanding of how these factors work it is still not possible to predict the outcome of a somaclonal breeding programme. New varieties have been produced by somaclonal variation, but in a large number of cases improved variants have not been selected because (1) the variation was all negative, (2) positive changes were also altered in negative ways, (3) the changes were not novel, or (4) the changes were not stable after selfing or crossing. Somaclonal variation is cheaper than other methods of genetic manipulation. At the present time, it is also more universally applicable and does not require ‘containment’ procedures. It has been most successful in crops with limited genetic systems and/or narrow genetic bases, where it can provide a rapid source of variability for crop improvement.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 18
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 46 (1990), S. 35-41 
    ISSN: 1573-5060
    Schlagwort(e): forage legumes ; Lotus corniculatus ; birdsfoot trefoil ; somaclonal variation ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Seventy-two plants regenerated from leaf-derived calli of a single plant of Lotus corniculatus have been evaluated for several morphological and agronomical traits. The analysis of selfed and polycross progenies of the regenerants indicates that the variation among regenerants was, at least in part, of genetic origin. Most of the mutations induced by tissue culture were recessive and were detected only after sexual propagation. Although in vitro culture had a depressive effect for most of the traits, the selfed progenies of 2 regenerants displayed higher values for leaflet width and seed yield than the selfed progeny of the initial plant. However the somaclonal variation did not increase the variation for any trait with respect to the variation of the donor cultivar of the initial plant.
    Materialart: Digitale Medien
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  • 19
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 48 (1990), S. 189-196 
    ISSN: 1573-5060
    Schlagwort(e): tissue culture ; Pyrus ; chimera ; anthocyanins ; segregation ; mutant ; variation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary An adventitious shoot regeneration system for Pyrus communis was used to separate two chimeral pears into their component genotypes. The two cultivars were a variegated type, ‘Louise Bonne Panachée’ and a red fruited mutant, ‘Red Hardy’. Leaves of these cultivars were placed onto a regeneration medium consisting of Nitsch & Nitsch (1969) salts supplied with various levels of Thidiazuron (TDZ) and NAA. After two months the regenerants were moved onto a proliferation medium of Lepoivre salts. Later they were evaluated for their chimeral status. Among the regenerants of the variegated type, 100% segregation occurred, most shoots were green, a few were albino. Regeneration was more efficient for dissociating the variegated chimera than rapid shoot multiplication and physical injury. In ‘Red Hardy’, after two months on the regeneration medium, 20 to 33% of the regenerants were green, the rest were red. The stability of the red and the green regenerants were assessed on media supplemented with various levels of sucrose and by total anthocyanins measurement. Both types were stable.
    Materialart: Digitale Medien
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  • 20
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 49 (1990), S. 249-253 
    ISSN: 1573-5060
    Schlagwort(e): Gossypium hirsutum ; cotton ; somatic embryogenesis ; callus ; tissue culture ; genetic control
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Three commercial varieties (Acala SJ-5, Coker 312 and Paymaster 303) and three exotic accessions (T1, T25 and T169) of cotton (Gossypium hirsutum L.) were tested for ability to undergo somatic embryogenesis. Sections of split petiole were cultured on 3 media and evaluated for embryogenesis after 180 days. Embryogenic T25 and Coker 312 plants were selected and crossed in a diallel with non-embryogenic Acala SJ-5, Paymaster 303, T1 and T169 plants. F1, F2 and BC1 populations were generated and tested for embryogenesis on a medium of MS salts and vitamins (1962) plus (per liter) 4.0 mg NAA, 1.0 mg Kn, 30 g glucose, 100 mg myo-inositol, 2.0 g Gelrite and 0.75 g MgCl2. Segregation for both occurrence and magnitude of embryogenesis was observed, suggesting the action of more than one gene.
    Materialart: Digitale Medien
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  • 21
    ISSN: 1573-5095
    Schlagwort(e): Norway spruce ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Somatic embryos were obtained from young, isolated cotyledons of Picea abies. A bud-inductive treatment for one week before transfer to a callus induction medium, resulted in a tenfold increase in the percentage of cotyledons in which embryonic tissues could be induced. The degree of expression of somatic embryogeny depends on whether cotyledons are first subjected to a callus-inducing medium or first exposed to a cytokinin treatment followed by a callus-inducing medium. It is hypothesized that two populations of cells exist, both with the inherent potential of becoming embryogenic after treatment with plant growth regulators.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 22
    ISSN: 1573-5117
    Schlagwort(e): callus ; Gelidium versicolor ; Grateloupia doryphora ; Laurencia sp. ; osmolality ; regeneration ; solidity ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Explants of Gelidium versicolor, Grateloupia doryphora and Laurencia sp. were cultivated in Provasoli enriched seawater culture medium (PES) adjusted to several osmolalities (0.5, 0.7, 1.0 and 1.5 Os kg−1) and solidities (agar concentration = 3, 8 and 15 g L−1). Osmolality was adjusted by dilution of seawater with distilled water (50, 70 and 100% seawater) and by NaCl addition. Explants of Laurencia sp. and Grateloupia doryphora showed bud regeneration and callus formation. Explants of Gelidium versicolor only showed bud regeneration. Osmolalities of 0.5 and 1.05 Os kg−1. inhibited or drastically reduced bud regeneration and callus formation. The highest callus formation and bud regeneration were observed at 0.7 to 1.0 Os kg−1. An increase in the agar concentration of the culture medium was positively correlated with callus formation and negatively correlated with bud regeneration. An increase in the percentage of seawater increased the solidity of the culture medium and was positively correlated with callus formation. Glycerol was an effective carbon source for the vegetative propagation of axenic explants of Grateloupia doryphora, promoting growth and bud regeneration. An increase in glycerol concentration in the culture medium increased its osmolality, inhibiting the growth of the explants and their morphogenetic development.
    Materialart: Digitale Medien
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  • 23
    ISSN: 1573-5117
    Schlagwort(e): Agardhiella subulata ; plant growth regulator ; seaweed ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract We examined whether auxins and cytokinins, either singly or in combination, stimulate cell division in tissue cultures of a red seaweed. Our experimental model consisted of filamentous and callus-like growths that developed from cross-sectional discs cut from young branches of Agardhiella subulata. Plant growth regulators were added to the medium to give combinations of an auxin with a cytokinin over a range of concentrations (1 µg L−1 −10 mg L−1). Several mixtures of auxins and cytokinins, as well as some single auxins, cytokinins and phenolics, stimulated cell division and growth in the tissue cultures beyond that of controls. The treatments that were effective included: phenylacetic acid/zeatin; phenylacetic acid/6-benzylaminopurine; α-naphthaleneacetic acid/zeatin; 2,4,5-trichlorophenoxyacetic acid/6-benzylaminopurine; and indoleacetic acid/kinetin. High concentrations of cytokinins (i.e. 10 mg L−1) inhibited the regeneration of plants in some of the cell cultures. These results provide further evidence that growth regulators can be used for the tissue culture of seaweeds and for the study of developmental phenomena in these plants.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 24
    ISSN: 1573-5044
    Schlagwort(e): Rubus ; thidiazuron ; kanamycin ; tissue culture ; cytokinins ; leaf organogenesis ; cotyledon organogenesis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Thidiazuron (TDZ), a substituted urea with cytokinin activity, was significantly more effective than benzyladenine (BA) at inducing organogenesis from detached Rubus cotyledons and leaves. The optimal TDZ concentration for organogenesis from cotyledons and leaves was 5–10 µM and 5–20 µM, respectively; however, shoot organogenesis occurred at TDZ concentrations of 0.5–5.0 µM. Light fluence rates from 0–81 µmol m-2 s-1 of continuous fluorescent light did not affect the percentage of organogenesis from cotyledons. Two weeks of continuous dark did not enhance the percentage of regeneration from leaf explants. Kanamycin, an antibiotic used to screen for transformation, severely reduced cotyledon growth and regeneration at concentrations as low as 10 mgl-1, and completely inhibited shoot organogenesis at 50 mgl-1.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 25
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 21 (1990), S. 1-8 
    ISSN: 1573-5044
    Schlagwort(e): cork oak ; micropropagation ; Quercus suber ; tissue culture ; rooting
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract This paper describes research on the application of tissue culture techniques to the micropropagation of cork oak (Quercus suber L.), a forest species of ecological and industrial importance in the Mediterranean area. Apical buds and nodal stem segments were employed as initial explants. Their origins were young seedlings, stump sprouts and sprouts formed on cuttings collected from old trees. The action of the mineral medium and growth regulators was studied in the multiplication stage. Media with low concentrations of ions, such as Sommer's or Heller's, are more suitable for growth and proliferation of explants than other media richer in salts. It was also observed that cytokinin (BA) must be present for the culture development. Adding low concentrations of auxin (NAA) to the medium improves the multiplication rate, especially in vegetative material of adult origin. The auxin type is the most important factor in the promotion of rhizogenesis. The method of application determines the quality of the root system. Treatment with low concentrations of IBA added to the rooting medium gives the best results. High sucrose concentration also improves rooting. Diluting the mineral rooting medium is slightly favourable, although there is no significant difference between it and the standard mineral concentration.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 26
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 21 (1990), S. 147-152 
    ISSN: 1573-5044
    Schlagwort(e): adventitious shoots ; histology ; Rosaceae ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Intact, flowering, rose plants have been regenerated in vitro from excised embryos of crosses between ‘Bridal Pink’ (the maternal parent) and several pollen parents. Explanted embryonic tissues developed into an organogenic callus which formed adventitious shoots after several months only on a modified half-strength Murashige & Skoog medium containing 1.0 μM BA and 0.05 μM NAA. These shoots could be separated, grown individually, rooted in a medium with no BA or NAA, with 1.0 μM IBA, and transplanted to greenhouse media. Embryos ranging in age from 21 to 35 days post-pollination formed organogenic callus that eventually regenerated adventitious shoots. Histological examination of normally-developing embryos showed that well-defined embryonic axes were beginning to develop at approximately 20–25 days postpollination. Analysis of populations of regenerated plants from different crosses showed differences in flower color, growth habit, peduncle length, and petal number. This system may be useful for irradiation-mutation breeding and/or for the development of transgenic rose plants using Agrobacterium tumefaciens.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 27
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 21 (1990), S. 185-189 
    ISSN: 1573-5044
    Schlagwort(e): ammonium nitrate ; Malus ; nitrogen ; potassium nitrate ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The influence of some macronutrients, especially NH4NO3 and KNO3, on root development of microcuttings from 3 apple scion cultivars is discussed. A reduction of the level of NH4NO3 in the medium from full strength to 1/4 strength significantly increased the percentage rooting of ‘Gala’ and ‘Royal Gala’, but not ‘Jonagold’. Further reduction of NH4NO3 level from 1/4 strength to zero significantly reduced the percentage of rooting in ‘Gala’ but not ‘Royal Gala’. ‘Jonagold’ rooted best at zero concentration NH4NO3. Without NH4NO3, rooting percentages were as high as 100% for all 3 cultivars when KNO3 was provided at full strength. The results show that adventitious roots can be induced on apple scion cultivars by media manipulation.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 28
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 22 (1990), S. 7-15 
    ISSN: 1573-5044
    Schlagwort(e): somaclone ; tissue culture ; meiosis ; isozyme
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Twenty genotypes (individual plants) of ‘Kentucky 31’ tall fescue (Festuca arundinacea Schreb., 2n=6x=42) were evaluated to determine regeneration response, and meiotic and isozyme changes in the regenerants. Six genotypes (K8, K16, K25, K27, P3 and P13) were selected for study of efficiency in producing calli and regenerating plants. Panicle pieces (3569) were plated on Schenk & Hildebrandt medium with one of three auxins, 2,4-D (2.0 mg 1-1), pCPA (3.8 mg 1-1) or 2,4,5-T (2.5 mg 1-1). Square-root transformed data were analysed as a completely randomized 6×3 factorial with genotype and auxin as the main effects. F-protected means were compared by the Waller-Duncan K-ratio T test. Genotype K8 produced significantly more calli per panicle piece (88/877), whereas genotype K25 regenerated significantly more plantlets per panicle piece (58/214) than the other genotypes. Callus production was significantly higher using 2,4-D (102/1244 calli per piece) than pCPA or 2,4,5-T. The type of auxin did not have a statistically significant effect on plant regeneration, which suggested that genotype was the most important variable. Twelve of the 210 regenerants were albino. Cytological evaluation of 95 green regenerants showed that all plants had 21 bivalents and pollen stainability ranged from 43.0–98.4%, which suggested all plants were male fertile. Zymograms of these 95 regenerants for ACPH, ADH, GOT, MDH, 6-PGD, PGI and SOD showed no differences from that of the parental genotype, which suggested that the green plantlets regenerated from somatic tissue.
    Materialart: Digitale Medien
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  • 29
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 23 (1990), S. 1-7 
    ISSN: 1573-5044
    Schlagwort(e): cotyledon culture ; genotypic differences ; plant growth-regulators ; plant regeneration ; tissue culture ; Vigna radiata
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Conditions for plant regeneration from excised cotyledons of Vigna radiata were studied. Complete plant developed from the uncallused proximal ends of cotyledons on Murashige & Skoog's (MS), Gamborg's (B5) and ‘C’ (MS salts + B5 vitamins) basal media. The basal medium ‘C’ was found to be best for plant regeneration. Regeneration frequency, however, varied with genotype, size, orientation and age of explant and the different plant growth regulators combination in the medium. Addition of cytokinins induced callusing at the proximal ends of cotyledons followed by multiple shoot formation. Out of 6-benzyl aminopurine (BAP), kinetin (KIN), N (Δ−2 isopentyl) adenine (2iP) and adenine sulphate (AS), only BAP and KIN were found to be more effective in enhancing the frequency of shoot regeneration. BAP at 1×10-1M induced maximum (60%) shoot regeneration whereas maximum number of shoots (8 to 9 shoots) per explant was observed with 5×10-6M BAP. Cotyledons excised from two-day old seedlings were most regenerative. The regenerative response of cotyledons decreased when sliced into two equal parts either longitudinally or transversely. Callusing and organogenic differentiation occured only if the petiolar end of cotyledons was in contact with medium. None of the tested treatments were effective in inducing shoot bud differentiation from subcultured callus. Well developed shoots rooted when incubated on half strength MS, MS and MS basal medium supplemented with IAA (5×10-6M). The rooted plants were transferred to pots and later established in the field with 60% success.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 30
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 23 (1990), S. 135-142 
    ISSN: 1573-5044
    Schlagwort(e): agar ; calcium ; cydonia ; mineral nutrition ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Shoot-tip cultures of Quince C (Cydonia oblonga Mill.) initiated on Murashige & Skoog (MS) medium containing 5 μM BA and 0.6% Phytagar showed both shoot-tip necrosis and severe vitrification. Culturing explants on medium containing 1.2% Phytagar and Ca levels of 3 mM (MS medium), 18 mM and 30 mM showed a decrease in growth with increasing medium Ca levels, being especially severe at 30 mM. The Ca content of the explants increased linearly with increasing medium Ca. Culturing explants on medium containing 3 mM, 9 mM, and 18 mM Ca at 0.6, 0.9, and 1.2% agar resulted in reduction in growth, shoot-tip necrosis, and vitrification when either factor was increased. The reduction in shoot-tip necrosis could be accounted for primarily by an increase in medium Ca levels but may also be affected by a change in explant growth. Increasing Ca concentration in the medium resulted in a linear increase in explant K, Ca, Mg, and B levels and a decrease in Mn and Na. Although increasing medium Ca or agar levels reduced vitrification, it is unclear whether they were the direct cause of the reduction in vitrification or whether this response was an effect of the reduction in culture fresh weight.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 31
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 23 (1990), S. 201-204 
    ISSN: 1573-5044
    Schlagwort(e): gelling agent ; suspension culture ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract A comparison of semi-solid vs. liquid embryo proliferation media was made using two Gossypium hirsutum L. genotypes (Coker 312 and T25) and two callus initiation media. Sections of petioles from mature, flowering plants were cultured on two modified Murashige and Skoog media. Medium 1 included 4.0 mg l-1 NAA and 1.0 mg l-1 kinetin; medium 2 contained 0.1 mg l-1 2,4-D and 0.1 mg l-1 kinetin. After six weeks, callus was removed from each explant and divided in half. One callus portion was placed in liquid proliferation medium and the other on semi-solid (0.2% Gelrite) proliferation medium. Composition of proliferation medium was identical to that of initiation medium, except no growth regulators were added. Embryos were counted after eight weeks. The percentage of explants forming callus was influenced by genotype/initiation medium combination. Analysis of variance procedures revealed significant variability for callus initiation media, proliferation media (semi-solid or liquid), and an initiation medium x genotype interaction. Paired t-tests indicated that more embryos were produced in liquid proliferation medium (227.3 embryos/culture) than on semi-solid proliferation medium (134.6 embryos/culture).
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 32
    Digitale Medien
    Digitale Medien
    Springer
    New forests 4 (1990), S. 63-66 
    ISSN: 1573-5095
    Schlagwort(e): European larch ; in vitro ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Adventitious buds were developed in vitro from stems of elongating short shoots of mature European larch (Larix decidua Mill.). Tissue culture propagule populations thus generated, were similarly remultiplied in vitro. Elongation and rooting were routine. No vitreous or otherwise abnormal shoots were noted.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 33
    Digitale Medien
    Digitale Medien
    Springer
    New forests 4 (1990), S. 67-79 
    ISSN: 1573-5095
    Schlagwort(e): elongation ; initiation ; rooting ; sprouts ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Three superior clones of Eucalyptus grandis hybrids were micropropagated through several steps. Five-year-old trees were girdled to induce juvenile sprouts. Cultures were attempted from mature branches and sprouts. Branches from mature trees were 100% contaminated while sprouts were only 40% contaminated. Pre-initiation hormone free medium and dark environment were used to screen for contaminants and to reduce production of phenolic compounds. Initiation of auxillary buds was achieved with modified MS plus 0.05 mg/l NAA and 0.5 mg/l BAR High multiplication rates were obtained on auxin-free medium with 0.6 mg/1 BAR Elongation of shoots was best on media with high auxin (2.5 mg/l of IBA) and cytokinin (1–1.5 mg/l of zeatin). Continual subculture on the multiplication medium improved rooting significantly. Up to 98% rooting was achieved on 1/4 MS with 2 mg/l IBA. Rooted propagules were successfully transferred to a mist greenhouse with 82% survival, and then to greenhouse conditions.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 34
    Digitale Medien
    Digitale Medien
    Springer
    Hydrobiologia 204-205 (1990), S. 375-380 
    ISSN: 1573-5117
    Schlagwort(e): callus ; Ecklonia cava ; Laminariales ; Phaeophyta ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Explants from stipes and meristems of Ecklonia cava were incubated on six media under several culture conditions. Both stipe and meristem explants developed calluses three to six weeks after inoculation onto all media except AS PC-1. Calluses developed on stipe explants but did not develop on meristem explants at a temperature of 23 °C. Temperatures from 8 to 13 °C were favorable for callus development. Callus development on meristem explants required light but callus development on stipe explants did not.
    Materialart: Digitale Medien
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  • 35
    ISSN: 1573-5060
    Schlagwort(e): aluminium toxicity ; soil acidity ; somaclonal variation ; sorghum ; Sorghum bicolor (L.) Moench ; tissue culture ; salt stress ; drought stress ; variants
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Sorghum bicolor (L.) Moench is generally quite sensitive to salt and acid (high aluminium) soil stresses, but quite tolerant of drought stress. As with any stress phenomenon, intra-specific variability exists within the genus. In vitro cell selection and somaclonal variation offer an alternative to traditional breeding methodology for generating improved breeding lines for hybrid development. A field selection protocol was developed for the three soil stresses and inter-stress evaluations were conducted in an effort to find multiple, stress-tolerant genotypes. The acid soil-drought stress, super-tolerant selections were located by the R7 generation when exposed to a combined aluminium-drought stress field environment and when the regeneration population (number of regenerated lines from one callus source) was maintained at 15,000 plants or higher. A variant frequency of 0.1 to 0.2% for stress tolerance and acceptable agronomic traits among the surviving somaclones, provided an adequate number of phenotypes with desirable agronomic characteristics and a high level of soil stress tolerance. Subsequent research verified that the stress-tolerant regenerants had superior acid soil and drought stress tolerance to that of the donor parents, that their yield capabilities under stress were superior to their parents, and that their stress tolerance attributes were transferred in hybrid combinations. In vitro selection was not effective in increasing the number of field stress survivors. In fact, superior germplasms were developed from non-stressed callus or salt-stressed callus. In vitro selection reduced regeneration frequency and subsequent survival of plants under field stress. In vitro-stressed regenerants should be subjected only to non-stressed environments to maintain population numbers for field selection and thereafter should be subjected to stress environments during later (R5+) generations. The optimal strategy for the exploitation of somaclonal variation may be through short-term cell culture (〈 12 months) with no attempt at in vitro selection.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 36
    Digitale Medien
    Digitale Medien
    Springer
    Plant and soil 129 (1990), S. 183-186 
    ISSN: 1573-5036
    Schlagwort(e): chlorosis ; Fe-efficiency ; sugarcane ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Iron deficiency in sugarcane is common on many calcareous soils of South India. The local cane cultivar Co 740 is found to be Fe-inefficient. During the present investigation callus-derived Fe-efficient lines were obtained through in vitro selectrion on Fe-stress MS medium. The Fe deficient basic medium was created by adding 100 mg CaCO3 and 0.5 mg Fe L-1 as FeEDTA in nutrient solution, and the pH was adjusted to 8.5 to impose stress conditions. The selected callus was used for producing shoot buds. The green shoots were further used for regeneration of roots. These selected seedlings were green, and grew continuously on the Fe-stress medium.
    Materialart: Digitale Medien
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  • 37
    ISSN: 1573-5060
    Schlagwort(e): β-glucuronidase ; plant ; silencing ; translational control ; 5′-untranslated region ; variation of gene expression
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Three random synthetic leaders and three naturally-occurring leaders, the tobacco mosaic virus (TMV) coat protein, the satellite tobacco necrosis virus (STNV) and the plant chlorophyll a/b-binding protein (Cab22L), were shown to modulate the β-glucuronidase reporter protein accumulation levels in transient expression experiments. The same chimeric constructs also confer differential distribution patterns of reporter protein accumulation in stably-transformed tobacco calli or regenerated transgenic plants. When the highest expression levels with a given leader are compared, the 31-nucleotide random leader stimulates translation 20- and 100-fold relative to the 9- and 4- nucleotide synthetic leaders respectively. However, this 31-nucleotide random leader is approx. 2 to 3-fold weaker than the 30-nucleotide STNV leader and even 5-fold weaker than both the 79-nucleotide TMV leader and the 66-nucleotide Cab22L leader. These results confirm the findings in transient expression experiments and stress the importance of the 5′-untranslated region for the production of heterologous proteins in transgenic plants.
    Materialart: Digitale Medien
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  • 38
    ISSN: 1573-5060
    Schlagwort(e): Agrobacterium ; plant regeneration ; potato ; Solanum tuberosum ; tissue culture ; transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary To provide a truly genotype-independent transformation system, it is necessary to be able to transform a wide range of potato genotypes. The ability to regenerate shoots in vitro was determined for 34 potato varieties using tuber disc explants. Following a culture regime used extensively in previous studies with the variety Desiree, half of the varieties could be regenerated from tuber discs and half could not. From a sample of varieties that could be regenerated from tuber discs, all but one variety gave transgenic plants. Twelve varieties were evaluated for the capacity to regenerate shoots from leaf and internode explants excised from in vitro grown plants. All of the varieties tested regenerated adventitious shoots. Leaf and internode explants from 5 varieties were subsequently used for transformation, and transgenic plants were produced from two potato varieties that did not give transgenic plants from tuber disc explants. Some varieties could not be transformed by either method, and will require modification of the in vitro regeneration and transformation system to be successful.
    Materialart: Digitale Medien
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  • 39
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 20 (1990), S. 7-14 
    ISSN: 1573-5044
    Schlagwort(e): genotype ; plant growth regulators ; Pisum sativum ; plant regeneration ; somatic embryogenesis ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Conditions were defined for plant regeneration via somatic embryogenesis in pea, using explants from immature zygotic embryos or from shoot apices. For the induction of somatic embryos, an auxin (picloram or 2,4-dichlorophenoxyacetic acid) was required. Embryogenic callus originated from embryonic axis tissue of immature embryos and from the axillary-bud region and the plumula of shoot apices. A clear effect of embryo size on somatic embryogenesis was shown. There were differences in frequency of somatic embryogenesis among the five genotypes used in the study. Additions of BA to auxin-containing medium reduced embryo production. Histological examinations confirmed the embryogenic nature of the immature embryo cultures and revealed that somatic embryos originated from the meristematic areas near the callus surface.
    Materialart: Digitale Medien
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  • 40
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 20 (1990), S. 41-46 
    ISSN: 1573-5044
    Schlagwort(e): papaya ; endophytic contamination ; rifampicin ; micropropagation ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract A procedure for in vitro propagation of dioecious papaya clones is described. A high rate of success in culture estbalishment was obtained when axillary buds were taken from lateral shoots of hedged rooted cuttings grown in a greenhouse. Seasonal endophytic contamination was suppressed by shaking propagules for 24 h in 300 mgl-1 rifampicin or by incorporating it at 50 mgl-1 into the medium. Murashige & Skoog (MS) basal medium supplemented with 0.5 mgl-1 6-benzyladenine and 0.1 mgl-1 naphthaleneacetic acid was used for establishment and proliferation. The addition of 160 mgl-1 adenine sulfate improved multiplication and shoot growth. An elongation stage on MS medium supplemented with 1.0 mgl-1 kinetin and 0.05 mgl-1 naphthaleneacetic acid was necessary before rooting. Rooting was obtained at a high rate on half-strength macroelements of MS medium supplemented with 1.0 mgl-1 indole-3-butyric acid. Commercial plots of papaya plants obtained through this procedure already exist.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 41
    ISSN: 1573-5044
    Schlagwort(e): chrysanthemum ; tissue culture ; regeneration
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Adventitious shoots were regenerated from leaf and stem explants of eleven chrysanthemum cultivars. The optimum medium for both explant types contained Murashige & Skoog basal medium supplemented with 5 μM 6-benzylaminopurine and 5 μM α-napthaleneacetic acid. Generally, stem explants were superior to leaf explants. There were large cultivar differences in shoot regeneration frequency with three cultivars failing to respond over a wide range of hormone combinations. Shoots on stem explants appeared mainly to originate from cortical cells which rapidly divided and ruptured the epidermis. Regenerated shoots could be easily rooted, transferred to glasshouse conditions, and grown to flowering. All regenerated plants had the same morphological characteristics compared to plants derived from nodes.
    Materialart: Digitale Medien
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  • 42
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 22 (1990), S. 167-172 
    ISSN: 1573-5044
    Schlagwort(e): bulbs ; dormancy ; lily ; micropropagation ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract We have studied the effect of various in-vitro conditions on dormancy of bulblets generated on scale explants of Lilium speciosum Thunb. cv. ‘Rubrum’ nr. 10. The bulblets were harvested after 11 weeks of culture. Dormancy was measured by determining the percent emergence in soil of viable, non-cold-treated bulblets. A study of the physical conditions showed that temperature had a strong effect on the induction of dormancy (15°C induced hardly any dormancy; 25°C induced a high level of dormancy), whereas short or long day and light or dark had no effect. Of the medium components, a low concentration of sucrose (1 gl−1 or less) or a high concentration of gibberellic acid (1 mg 1−1) reduced the level of dormancy. Application of various concentrations of abscisic acid, 6-benzylaminopurine, α-naphthaleneacetic acid, indole-3-acetic acid, 2,3,5-triiodobenzoic acid or a Murashige and Skoog macro- and microelement mixture did not affect the dormancy status.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 43
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 20 (1990), S. 131-135 
    ISSN: 1573-5044
    Schlagwort(e): L-ascorbic aid ; dehydroascorbic acid ; tissue culture ; medium
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Ascorbic acid rapidly decays in plant tissue culture media. Within 50 min to 3 h after preparing 100 mM solutions, ascorbic acid was destroyed. Autoclaving, shaking flasks, high light intensity and increasing pH over a range from 4.5–7 accelerated decay. Ascorbic acid was oxidized to dehydroascorbic acid which also underwent decay. Within 11 h and 15 min after adding ascorbic acid both ascorbic acid and its oxidation product, dehydroascorbic acid, disappeared from medium. Since ascorbic acid is rapidly destroyed in plant tissue culture media it may not exert its effect as an intact molecule. Instead its antioxidant/antibrowning role in plant cell, tissue and organ cultures may be mediated by some product of further oxidation.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 44
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 20 (1990), S. 137-140 
    ISSN: 1573-5044
    Schlagwort(e): Citrus unshiu ; embryogenesis ; juice vesicle ; plantlet formation ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Callus was induced from juice vesicles of satsuma mandarin on Murashige & Skoog medium supplemented with α-naphthaleneacetic acid (NAA), kinetin (K) and gibberellin (GA). Adventitious embryoids arose from the callus tissue on the medium containing 1 mgl−1 NAA alone. The embryoids grew into embryos which resulted in a plantlet on medium containing 1 mgl−1 GA.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 45
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 20 (1990), S. 157-163 
    ISSN: 1573-5044
    Schlagwort(e): auxin ; 2,4-D ; long-term regeneration ; picloram ; Saccharum ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Long-term regeneration of sugarcane (Saccharum spp. hybrid and Saccharum spontaneum L.) callus cultures was achieved by selection of green callus on MS agar medium containing 0.5 mgl-1 picloram or 2,4-D. Newly initiated sugarcane callus cultures were a complex mixture of different tissue types including white, nonregenerative and green, regenerative tissues. The proportion of the tissue types changed as a function of time in culture, genotype, and amount and kind of auxin. Green callus on picloram media always regenerated green plants. Nine hybrids and ten wild relatives of sugarcane produced green calli on picloram media whereas only three hybrids were grown as green calli on 2,4-D media in long-term culture. Green calli were inoculated into liquid MS medium with 0.5 mgl-1 picloram for suspension culture. These cultures were totipotent after 19 months. For routine culture, we initiated callus cultures on modified MS medium with 3 mgl-1 2,4-D, then in two to three weeks we subcultured callus on MS medium with 0.5 mgl-1 picloram and selected for green callus. Green calli regenerated large numbers of green plants after more than four years.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 46
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 20 (1990), S. 165-172 
    ISSN: 1573-5044
    Schlagwort(e): activated charcoal ; 2,4-D adsorption ; coconut palm ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The rate of adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D) by activated charcoal (AC) from liquid and semi-solid tissue culture media was determined using 2-[14C]-2′,4′-D. In liquid medium 99.5% of the added 2,4-D (10-4 M) was adsorbed by AC (2.5 gl-1) within 5 days of preparation of the medium. Higher 2,4-D levels of reduced AC concentrations increased the level of available 2,4-D in the medium and extended the period necessary for the level of 2,4-D in the medium to become stabilized. In semi-solid medium the rate of adsorption of 2,4-D by AC was considerably reduced. A stable ratio of gel/2,4-D:AC/2,4-D was only reached after 10 to 20 days, depending on the 2,4-D concentration used. Low pH levels and maintenance of the medium at higher temperatures (20–30°C) accelerated the adsorption of 2,4-D by AC. In vitro tissue cultures of coconut palm showed marked differences in their growth response according to the age of the medium used and the associated variations in 2,4-D concentrations.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 47
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 21 (1990), S. 79-82 
    ISSN: 1573-5044
    Schlagwort(e): Drosera capensis ; Drosera natalensis ; plumbagin ; Plumbago auriculata ; secondary metabolites ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The rapid clonal multiplication of two species of South African Drosera is described. Levels of plumbagin, (5-hydroxy-2-methyl-1,4-naphthoquinone) from in vivo and in vitro grown plants are compared to those present in Plumbago roots. P. auriculata Lam. roots contained more than twice as much plumbagin as in vivo grown D. capensis L. plants which in turn contained more than twice as much as comparable plants of D. natalensis Diels. It is concluded that the extraction of plumbagin from Drosera plants is not commercially feasible.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 48
    ISSN: 1573-5044
    Schlagwort(e): tissue culture ; acclimatization ; plantlet quality ; adventitious rooting ; Douglas fir
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The objective of this investigation was to test for the possible effects of plantlet morphology and environmental stress on survival and growth during the acclimatization of tissue-cultured Douglas fir [Pseudotsuga menziesii (Mirb.) Franco]. Under a high-stress environmental regime of 40–70% relative humidity and 22–28°C, survival was 33%, compared to 89% under a low-stress regime of 80–90% RH and 15–20°C. Shoot elongation under low stress was twice as great as that under high stress. Certain morphological features were associated with improved survival under high stress, and they included a large (10+) root number, tall (40 + mm) shoots, and upright needles. Plantlets with 10 + roots had 52% survival, compared to 25% or 31% for those with 1–3 or 4–10 roots, respectively. Also, plantlets with an initial shoot height of 41–60 mm had a 53% survival rate compared to 20% or 37% for those with 21–30 mm or 31–40 mm shoots. Tall plantlets and those with 10+ roots also underwent the greatest shoot elongation during the 7 week observation period. However, plagiotropism was frequent on tall shoots.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 49
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 23 (1990), S. 49-58 
    ISSN: 1573-5044
    Schlagwort(e): anther culture ; embryoids ; poplars ; tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Anthers of Populus maximowiczii with microspores at the mononucleate stage were cultured at 20°C in the dark on agar-solidified Murashige and Skoog medium after 4 days of cold treatment (4°C). After 4 to 8 weeks anthers on medium supplemented with 0.5, 1.0 or 2.0 mg l-1 2,4-D in combination with 0.1 mg l-1 kinetin developed calli that were characterized by smooth surface and gel-like consistency. These calli were comprised of expanding microspores surrounded by a mucilaginous matrix. After transfer of anthers with embryogenic calli to MS medium with low hormone levels (NAA at 0, 0.1 and 0.1 mg l-1 and BA at 0, 0.1 and 1.0 mg l-1) microspores started to divide and initiated independent meristematic nests, which developed into embryoidal structures, resembling globular to bi-polar heart-shaped embryoids. The embryoids germinated precociously without developing cotyledons. After transfer to medium with a range of levels of BA (1.0, 2.5 and 5.0 mg l-1), adventitious shoots developed mainly from the roots. Shoots were rooted in half strength MS medium supplemented with 0.025 mg l-1 NAA. Via this pathway anther response in the best treatment combination was 10%.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 50
    Digitale Medien
    Digitale Medien
    Springer
    Journal of chemical ecology 16 (1990), S. 931-939 
    ISSN: 1573-1561
    Schlagwort(e): Allelopathy ; Antennaria microphylla ; small everlasting ; Euphorbia esula ; leafy spurge ; tissue culture ; hydroquinone ; arbutin ; glucosyltransferase ; biotransformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Media and media extracts from callus cultures of small everlasting (Antennaria microphylla) inhibited leafy spurge (Euphorbia esula L.) callus tissue and suspension culture growth (50 and 70% of control, respectively) and were phytotoxic in lettuce and leafy spurge root elongation bioassays (64 and 77% of control, respectively). Hydroquinone, a phytotoxic compound previously isolated from small everlasting, was also biosynthesized by callus and suspension cultures of this species. Exogenously supplied hydroquinone (0.5 mM) was toxic to leafy spurge suspension culture cells and was only partially biotransformed to its nontoxic water-soluble monoglucoside, arbutin, by these cells. This report confirms the chronic involvement of hydroquinone in the allelopathic interaction between small everlasting and leafy spurge.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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