Introduction of Plasmids into Azospirillum brasilense by Electroporation

Abstract

The genus Azospirillum comprises Gram N₂ fixing soil bacteria living in close association with the roots of numerous plants. Field trials, carried out at different locations have demonstrated significant plant growth promotion upon Azospirillum inoculation. Based on 16S rRNA similarity, the genus Azospirillum has been classified within the alpha subdivision of Proteobacteria. Plasmids of the IncP group are stably maintained in a wide range of Azospirillum strains and can be succesfully transferred to Azospirillum either by conjugation or by electroporation. As compared to conjugation, the electroporation technique offers the advantages of being much faster and avoiding problems with counterselection of the Escherichia coli donor strain.