Plant and Soil

, Volume 188, Issue 1, pp 77–82

A study of the symbiotic importance and location of nod gene inducing compounds in two widely nodulating and two non-nodulating tropical tree species


  • John E. Shaw
    • Department of Biological SciencesUniversity of Dundee, Millers Wynd
  • Tom Reynolds
    • Plant Biochemistry, Jodrell LaboratoryRoyal Botanic Gardens, Kew, Richmond
  • Janet I. Sprent
    • Department of Biological SciencesUniversity of Dundee, Millers Wynd

DOI: 10.1023/A:1004212330945

Cite this article as:
Shaw, J.E., Reynolds, T. & Sprent, J.I. Plant and Soil (1997) 188: 77. doi:10.1023/A:1004212330945


Previous work led us to consider the role of nod gene-inducing compounds in related nodulating and non-nodulating Acacia species. Could the nodulation status of the non-nodulating plants be determined by an inability to produce and exude compounds that the related nodulating species were capable of delivering to the rhizobial symbionts? Also, it seemed to have been assumed previously that results gathered for extracts of seedlings or root tissue would reflect the situation for compounds exuded freely into the rhizosphere. The growth medium used in this investigation gave an opportunity to test this theory with the added bonus of allowing root exudates to be collected from a limited number of plants. The two non-nodulating species were found to lack neither the ability to produce potentially inducing compounds nor the means to exude them into the rhizosphere. However, it was demonstrated, through the distribution of potentially inducing compounds within the plants and their exudates, that the components of tissue extractions did not necessarily reflect the components exuded into the rhizosphere.

AcaciaFaidherbiaflavonoidsnod genesnon-nodulatingrhizobia

Copyright information

© Kluwer Academic Publishers 1997