Lena Ström
Professor
Exudation of low molecular weight organic acids by germinating seeds of two edaphic ecotypes of Silene nutans L.
Author
Summary, in English
Two parapatric ecotypes of Silene nutans, exhibiting distinct allozyme patterns, morphology and autecology were investigated for differences in exudation of low molecular weight organic acids from germinating seeds, and for differences in seed phosphorus content. The calcicolous ecotype is restricted to calcareous soils, and the silicicolous one predominantly occurs on acid soils, and sometimes, although less frequently, on neutral to alkaline soils. No clear difference was found between ecotypes. However, within the silicicolous ecotype seed samples showed marked differences in exudation pattern and seed phosphorus content depending on origin along the soil acidity gradient. Seeds of low-pH origin exuded more dicarboxylic acids (malic + succinic acid, oxalic acid) and had a lower phosphorus content than seeds of high pH origin. The exudation of dicarboxylic acids from seeds of low pH origin is probably an adaptation to adverse conditions (aluminium toxicity) on acid soils. The pattern is similar to that found among different cultivars of wheat. It is contrasted to the pattern found on comparison of a suite of calcifugous and calcicolous species, where exudation of di- and tricarboxylic acids is associated with solubilisation of recalcitrantly bound phosphorus and iron in calcareous soils. (C) 2001 Editions scientifiques et medicales Elsevier SAS.
Department/s
- Department of Biology
- Dept of Physical Geography and Ecosystem Science
Publishing year
2001
Language
English
Pages
285-291
Publication/Series
Acta Oecologica
Volume
22
Issue
5-6
Document type
Journal article
Publisher
Elsevier
Topic
- Ecology
Keywords
- ecotype
- root exudation
- Silene nutans
- soil acidity
- seed phosphorus content
Status
Published
ISBN/ISSN/Other
- ISSN: 1146-609X