Biology and Fertility of Soils

, Volume 15, Issue 4, pp 259–267

Rhizodeposition and net release of soluble organic compounds by pine and beech seedlings inoculated with rhizobacteria and ectomycorrhizal fungi

  • Corinne Leyval
  • Jacques Berthelin
Article

DOI: 10.1007/BF00337210

Cite this article as:
Leyval, C. & Berthelin, J. Biol Fertil Soils (1993) 15: 259. doi:10.1007/BF00337210

Summary

A lysimetric experiment was performed in a greenhouse to evalute root deposition and net release of soluble organic compounds after 1 and 2 years from pine and beech seedlings inoculated with an ectomycorrhizal fungus (Laccaria laccata) and/or rhizobacteria (Agrobacterium radiobacter for beech and Agrobacterium sp. for pine). Total C compounds released in the rhizosphere of both plants increased after inoculation with the bacteria or ectomycorrhizal fungus. The rhizobacteria increased root and plant growth and rhizodeposition, but the mycorrhizal fungi appeared to increase only root deposition. Soluble C compounds, collected after 2 years, represented only 0.1–0.3% of the total C compounds released into the rhizosphere, and were modified by inoculation with the microorganisms. After inoculation with the bacteria, levels of sugars and amino acids decreased in pine and beech rhizospheres, whereas organic acids increased, especially in the pine rhizosphere. In the rhizosphere of mycorrhizal beeches, sugar and amino acids increased, and organic acids differed from those released from non-mycorrhizal beeches. In the mycorrhizal pine rhizosphere, however, all compounds decreased. Following dual inoculations, mycorrhizal colonization increased, no effect on plant growth was observed, and virtually no organic acids were detected.

Key words

Ectomycorrhizae Rhizobacteria Rhizodeposition Soluble organic compounds Pine Beech Laccaria laccata Agrobacterium radiobacter 

Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • Corinne Leyval
    • 1
  • Jacques Berthelin
    • 1
  1. 1.Centre de Pédologie Biologique, Centre National de la Recherche ScientifiqueLaboratoire associé à l'Université de Nancy IVandoeuvre-les-Nancy CedexFrance