Mycorrhiza

, Volume 6, Issue 5, pp 403–408

Phosphorus amendment inhibits hyphal branching of the VAM fungus Gigaspora margarita directly and indirectly through its effect on root exudation

  • G. Nagahashi
  • D. D. Douds Jr.
  • G. D. Abney
ORIGINAL PAPER

DOI: 10.1007/s005720050139

Cite this article as:
Nagahashi, G., Douds Jr., D. & Abney, G. Mycorrhiza (1996) 6: 403. doi:10.1007/s005720050139

Abstract

 The effect of solution phosphorus (P) concentration upon growth of pregerminated spores of the vesicular-arbuscular mycorrhizal fungus Gigaspora margarita was examined in vitro. P at 1 mM significantly inhibited branching of the primary germ tube. The number of branches and the total hyphal length were both significantly inhibited at 10 mM P. In addition, germinated spores exposed to exudates produced by Ri T-DNA-transformed roots of Daucus carota L. grown in the presence of P showed significantly less hyphal branching than those exposed to exudates produced by P-stressed roots. These phenomena could contribute to the observed inhibition of mycorrhiza formation by high P.

Key words Gigaspora margaritaPhosphorusExudationHyphal branching

Copyright information

© Springer-Verlag Berlin Heidelberg 1996

Authors and Affiliations

  • G. Nagahashi
    • 1
  • D. D. Douds Jr.
    • 1
  • G. D. Abney
    • 1
  1. 1.USDA-ARS ERRC, 600 E. Mermaid Lane, Wyndmoor, PA 19038-8038, USAUS