Titelangaben
Frensch, Jürgen ; Hsiao, Theodore C. ; Steudle, Ernst:
Water and solute transport along developing maize roots.
In: Planta.
Bd. 198
(1996)
Heft 3
.
- S. 348-355.
ISSN 0032-0935
DOI: https://doi.org/10.1007/BF00620050
Abstract
Hydraulic and osmotic properties were measured along developing maize (Zea mays L.) roots at distances between 15 and 465 mm from the root tip to quantify the effects of changes in root structure on the radial and longitudinal movement of water and solutes (ions). Root development generated regions of different hydraulic and osmotic properties. Close to the root tip, passive solute permeability (root permeability coefficient, P-sr was high and selectivity (root reflection coeffcient, sigma(sr)) low, indicative of an imperfect semipermeable root structure. Within the apical 100-150 mm, P-sr decreased by an order of magnitude and sigma(sr), increased significantly. Root hydraulic conductivity (Lp(r)) depended on the nature of the force (hydrostatic and osmotic). Osmotic Lp(r) was smaller by an order of magnitude than hydrostatic Lp(r) and decreased with increasing distance from the root tip. Throughout the root, responses in turgor of cortical cells and late metaxylem to step changes in xylem pressure applied to the base of excised roots were measured at high spatial resolution. The resulting profiles of radial and longitudinal propagation of pressure showed that the endodermis had become the major hydraulic barrier in older parts of the root, i.e. at distances from the apex > 150 mm. Other than at the endodermis, no significant radial hydraulic resistance could be detected. The results permit a detailed analysis of the root's composite structure which is important for its function in collecting and translocating water and nutrients.
Weitere Angaben
Publikationsform: | Artikel in einer Zeitschrift |
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Begutachteter Beitrag: | Ja |
Zusätzliche Informationen: | BAYCEER33666 |
Institutionen der Universität: | Forschungseinrichtungen > Forschungszentren > Bayreuther Zentrum für Ökologie und Umweltforschung - BayCEER Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Biologie > Lehrstuhl Pflanzenökologie Fakultäten Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Biologie Forschungseinrichtungen Forschungseinrichtungen > Forschungszentren |
Titel an der UBT entstanden: | Ja |
Themengebiete aus DDC: | 500 Naturwissenschaften und Mathematik |
Eingestellt am: | 24 Sep 2015 09:39 |
Letzte Änderung: | 24 Sep 2015 09:39 |
URI: | https://eref.uni-bayreuth.de/id/eprint/19746 |