ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
Collection
Publisher
Years
  • 1
    Electronic Resource
    Electronic Resource
    Boron compartmentation in roots of sunflower plants of different boron status: A study using the stable isotopes 10B and 11B adopting two independent approaches (2001)
    Copenhagen : Munksgaard International Publishers
    Physiologia plantarum 113 (2001), S. 0 
    Details
    ISSN: 1399-3054
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: The intracellular compartmentation of boron (B) in roots of sunflower plants precultured with 100 μM B (high B) or 1 μM B (low B) was studied using two independent approaches. In the first approach, short-term efflux studies using the stable isotopes 11B and 10B were carried out. In roots of high B plants, the calculated concentrations of B (nmol gFW −1) were 52.6 in the cell wall, 7.5 in the vacuole, 27.1 in the cytosol and 48.0 in the free space. In roots of low B plants, the concentrations of B (nmol gFW −1) were 43.4 in the cell wall, 2.8 in the vacuole, 17.9 in the cytosol and almost zero in the free space. Although the B supply differed by a factor 100, the B concentrations in the cytosol and the vacuole of low B plants were 66 and 37% of the respective concentrations in high B plants. This suggests an additional role for B in plant metabolism, besides its function in the cell wall. In the second approach, root B pools (cell sap and water-insoluble residue) were determined for comparison, and found to be in good agreement with the results from the efflux study.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1034/j.1399-3054.2001.1130307.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Are there connections between phenol metabolism, ascorbate metabolism and membrane integrity in leaves of boron-deficient sunflower plants? (1998)
    Copenhagen : Munksgaard International Publishers
    Physiologia plantarum 104 (1998), S. 0 
    Details
    ISSN: 1399-3054
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: The influence of soluble phenol concentration and polyphenoloxidase activity in leaves of both B-deficient and B-sufficient sunflower plants (Helianthus annuus L. cv. Frankasol) on plasma membrane permeability was investigated, A study was also undertaken as to whether or not the incubation of B-deficient leaves in ascorbate- and calcium-containing solutions has a beneficial effect on plasma membrane integrity. Plants were cultivated under controlled environmental conditions with deficient and sufficient B supply and different light intensity to provoke changes in phenol metabolism. Analysis of membrane permeability (measured by potassium efflux), soluble phenol concentration and polyphenoloxidase (EC 1.10.3.1) activity of leaves showed that there was no correlation between these parameters. Furthermore, incubation in solutions containing ascorbate and calcium did not decrease the enhanced membrane permeability due to B deficiency, which could, however, be lowered by boric acid application. In summary, the results suggest that B does not maintain plasma membrane integrity by complexing phenols or inhibiting polyphenoloxidase activity, thereby preventing damage by oxygen free radicals. Ascorbate metabolism or calcium-related disorders seem also not to be involved. It is therefore likely that B has a direct function at the membrane, possibly by stimulating membrane-related enzymes, or in a structural role similar to that reported for the cell wall.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1034/j.1399-3054.1998.1040325.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Effects of boron starvation on boron compartmentation, and possibly hormone-mediated elongation growth and apical dominance of pea (Pisum sativum) plants (2001)
    Copenhagen : Munksgaard International Publishers
    Physiologia plantarum 111 (2001), S. 0 
    Details
    ISSN: 1399-3054
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Two experiments were carried out to study the effects of boron (B) deficiency on 7-day-old pea plants for 6 or 9 days under controlled growth chamber conditions. Growth and apical dominance (AD) of the plants and their B concentration and compartmentation were followed throughout the starvation period. Additionally, auxin (indoleacetic acid, IAA) concentration in the shoot apex and polar transport from it were measured along with the cytokinin (CK) concentration in the shoot apex and the roots. The results demonstrate that during a 6-day B-deficiency period, B concentration in the water-insoluble residue of the roots was very stable and could not easily be reduced. In contrast, B concentration in the cell sap fraction was very sensitive to external B supply. Twelve hours after transferring the plants from B-sufficient to B-deficient solutions, the B concentration in root cell sap declined to half the concentration of the control plants. In addition, B concentration in the new aerial plant parts, which developed after the onset of the B-deficiency treatment, was extremely low. A decline in elongation growth could be observed as soon as about 4 days after the imposition of B deficiency. This preceded the first measurable growth of lateral buds (release from AD). Before the onset of these morphological changes, there was a considerable decline in CK concentration, accompanied by a dramatic decrease in IAA export out of the shoot apex, a decline in IAA concentration in the shoot apex and the roots and a reduced capacity for polar IAA-transport. These changes are discussed as possible reasons for the observed reduction in elongation growth and AD. These hormonal changes themselves are possibly the result of the decreased symplasmic B concentration, which in turn may be responsible for the reduced concentration in apical CKs. A sequence of events, which may be causally related, is suggested to explain the effects of B deficiency on the growth and AD of pea plants.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1034/j.1399-3054.2001.1110212.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...