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
  • 1
    Electronic Resource
    Electronic Resource
    Suberized bundle sheaths in grasses (Poaceae) of different photosynthetic types I. Anatomy, ultrastructure and histochemistry (1988)
    Springer
    Protoplasma 142 (1988), S. 92-111 
    Details
    ISSN: 1615-6102
    Keywords: Bundle sheath ; Histochemistry ; Mestome sheath ; Phenols ; Suberin ; Suberized lamellae ; C4 grasses
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We investigated the histochemistry and ultrastructure of the cell walls of mestome sheaths and parenchymatous bundle sheaths of ten species of grasses. The species surveyed included representatives from all the major photosynthetic types: C3-Bromus tectorum, Phalaris arundinacea; C4/NAD-ME-Eragrostis cilianensis, Panicum capillare; C4/NAD-ME/PCK-Bouteloua curtipendula; C4/PCK-Chloris gayana, Sporobolus elongatus; C4/NADP-ME-Echinochloa crus-galli, Setaria glauca, Themeda triandra. All vein orders (designated here as major, minor and transverse) from mature leaves of each species were tested histochemically for lipids and phenols, and the majority of species were also examined with the electron microscope. A suberized lamella was detected ultrastructurally in at least some walls of major vein bundle sheath cells of all species examined. These lamellae were also present in some cells associated with the minor veins of the C3 species and in the minor and transverse veins of the C4/NADP-ME species. Histochemical tests for lipids and phenols consistently failed to differentiate this layer. Based on these tests, none of the vein orders in any species showed evidence of a Casparian band. In all suberized bundle sheaths, the compound middle lamella between cells with suberin lamellae is modified by the presence of phenols. These did not, however, confer resistance to acid digestion to the cell layer, in contrast to cell layers with Casparian bands. Therefore, although the mestome sheath has some features in common with the root endodermis (i.e. cells with a suberized lamella and thick, cellulosic walls which may be further modified), we could find no substantive anatomical or ultrastructural evidence for the presence of a Casparian band in any of the grass leaves investigated. The significance of these observations is discussed in the context of apoplastic permeability of these walls.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01290867
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Suberized bundle sheaths in grasses (Poaceae) of different photosynthetic types. II. Apoplastic permeability (1988)
    Springer
    Protoplasma 142 (1988), S. 112-126 
    Details
    ISSN: 1615-6102
    Keywords: Pyrenetrisulfonate ; Bundle sheath ; Mestome sheath ; C4 grasses ; Apoplastic movement ; Hydraulic conductivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The relative hydraulic conductivities of major and minor longitudinal veins, and the apoplastic permeability of the bundle sheaths surrounding all longitudinal and transverse veins were investigated in representatives of the C3, C4/NAD-ME, C4/NAD-ME/PCK intermediate, C4/PCK and C4/NADP-ME photosynthetic types. Using the Hagen-Poiseuille equation and measurements of tracheary element diameters, the number of elements in each vein type and the numbers of each vein type, we calculated that 87–99% of the water flow in a longitudinal direction would be expected to occur in the major veins. The permeability of the mestome sheaths and parenchymatous bundle sheaths surrounding the veins was tested using the negatively-charged, fluorescent dye, trisodium 3-hydroxy-5,8,10-pyrenetrisulfonate (PTS). This dye proved nontoxic to plant tissue at a concentration of 0.5%, according to a deplasmolysis test with onion epidermal strips. The PTS concentration achieved in the tested grass leaves was about 0.035%, well below the toxic limit. When a solution of PTS was fed to the leaves by means of a basal cut, the dye moved into the veins of all orders. From there, it moved outward into the surrounding tissues, indicating that the sheaths surrounding the veins of all orders in all species tested were permeable. Therefore, contrary to previous predictions based on structural observations and some tracer studies, bundle sheaths with suberized cell walls do not function as endodermal layers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01290868
    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...