This title appears in the Scientific Report :
2002
Please use the identifier:
http://dx.doi.org/10.1093/jxb/erf011 in citations.
The fungal sheath of ectomycorrhizal pine roots : an apoplastic barrier for the entry of calcium, magnesium, and potassium into the root cortex?
The fungal sheath of ectomycorrhizal pine roots : an apoplastic barrier for the entry of calcium, magnesium, and potassium into the root cortex?
The apoplastic permeability of the fungal sheath of two different ectomycorrhizal associations of Pinus sylvestris L. was analysed by laser microprobe mass analysis (LAMMA) and energy-dispersive X-ray spectroscopy (EDXS) after stable isotope labelling with Mg-25, K-41 and Ca-44. Entry of Mg-25 and C...
Saved in:
Personal Name(s): | Bücking, H. |
---|---|
Kuhn, A. J. / Schröder, W. H. / Heyser, W. | |
Contributing Institute: |
Phytosphäre; ICG-III |
Published in: | The @journal of experimental botany, 53 (2002) S. 1659 - 1669 |
Imprint: |
Oxford
Univ. Press
2002
|
Physical Description: |
1659 - 1669 |
DOI: |
10.1093/jxb/erf011 |
Document Type: |
Journal Article |
Research Program: |
Chemie und Dynamik der Geo-Biosphäre |
Series Title: |
Journal of Experimental Botany
53 |
Subject (ZB): | |
Publikationsportal JuSER |
The apoplastic permeability of the fungal sheath of two different ectomycorrhizal associations of Pinus sylvestris L. was analysed by laser microprobe mass analysis (LAMMA) and energy-dispersive X-ray spectroscopy (EDXS) after stable isotope labelling with Mg-25, K-41 and Ca-44. Entry of Mg-25 and Ca-41 into the outer cortical apoplast of non-mycorrhizal roots was detected after 4 min of labelling. After a longer exposure time the endodermis with its Casparian band acted as an efficient apoplastic diffusion barrier for the radial movement of Mg-25 and Ca-44 into the stele. A fraction of approximately one-third of the apoplastic cations of the root cortex could not be exchanged against the external label even after longer exposure times. The ectomycorrhizal sheath of the two fungal species used, Pisolithus tinctorius (Pers.) Coker & Couch and Suillus bovinus (L. ex Fr.) Kuntze, does not completely inhibit the apoplastic movement of ions into the mycorrhizal root cortex, but retarded the penetration of isotopes into the cortical apoplast. In roots inoculated with S. bovinus, a clear labelling of the cortical apoplast could first be detected after 24 h of exposure to the stable isotope solution. At this time the labelling of the cortical apoplast in these mycorrhizal roots was higher than those of non-mycorrhizal roots and, with EDXS, changes in the element composition of the apoplast were detected. The results indicated that possibly hydrophobins localized in the fungal cell wall might be involved in the increased hydrophobicity of mycorrhizal roots and the lower permeability of the ectomycorrhizal sheath. |