Table of Contents
Journal of Botany
Volume 2011, Article ID 702947, 8 pages
Review Article

Composite Actinorhizal Plants with Transgenic Roots for the Study of Symbiotic Associations with Frankia

1Institut de Recherche pour le Développement (IRD), 911 avenue Agropolis, BP 64501, 34394 Montpellier Cedex 5, France
2Laboratoire de Génétique, Biochimie et Biotechnologies Végétales, Département de Biologie et d'Ecologie, Université Mentouri, Route Ain El Bey, Constantine, Algeria
3Institute of Forest Genetics and Tree Breeding, Forest Campus, R. S. Puram, Coimbatore 641002, India
4Laboratorio de Bioquímica, Microbiología e Interacciones Biológicas en el Suelo (LBMIBS), Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, R. Sáenz Peña 352, Bernal B1876BXD, Argentina

Received 8 July 2011; Accepted 24 August 2011

Academic Editor: Johann Greilhuber

Copyright © 2011 Faïza Meriem Benabdoun et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


More than 200 species of dicotyledonous plants belonging to eight different families and 24 genera can establish actinorhizal symbiosis with the nitrogen-fixing soil actinomycete Frankia. Compared to the symbiotic interaction between legumes and rhizobia, little is known about the molecular basis of the infection process and nodule formation in actinorhizal plants. Here, we review a gene transfer system based on Agrobacterium rhizogenes that opens the possibility to rapidly analyze the function of candidate symbiotic genes. The transformation protocol generates “composite plants” that consist of a nontransgenic aerial part with transformed hairy roots. Composite plants have already been obtained in three different species of actinorhizal plants, including the tropical tree species Casuarina glauca, the Patagonian shrub Discaria trinervis, and the nonwoody plant Datisca glomerata. The potential of this technique to advancing our understanding of the molecular mechanisms underlying infection by Frankia is demonstrated by functional analyses of symbiotic genes.