Fluorescent Pseudomonas species categorized by using polymerase chain reaction (PCR)/restriction fragment analysis of 16S rDNA


  • This paper is the result of a collaborative research between two groups. One (INRA, Laboratoire de Microbiologie des Sols, Dijon) is working on the ecology of rhizobia; within this group, Dr G. Laguerre develops molecular techniques to analyse diversity of Rhizobium populations. The other group (INRA, Laboratoire de Recherches sur la Flore Pathogene du Sol, Dijon) is engaged in studies on biological control of soil-borne diseases; within this group, Dr P. Lemanceau is in charge of a research project on the ecology of fluorescent pseudomonads applied to the biological control of soil-borne diseases such as fusarium-wilts. L. Rigottier-Gois is a student who took part actively to this study.

INRA, Laboratoire de Microbiologic des Sols, 17, rue Sully, BV. 1540, 21034 Dijon Cedex, France. Fax 33 80 63 32 24. Tel. 33 80 63 30 93.


A rapid procedure for the identification of fluorescent pseudomonads, based on the polymerase chain reaction (PCR) and restriction fragment analysis of 16S rDNA genes is described. Thirty-one strains belonging to 10 different Pseudomonas species of the Pseudomonas fluorescens rRNA branch were characterized. Amplified rDNA was digested with 13 different restriction endonucleases. The combined data from restriction analysis enabled the definition of 17 different 16S rDNA genotypes. All type strains belonging to different species were differentiated. The good correlation between grouping obtained using restriction analysis with other molecular classification criteria demonstrates the value of the described method to characterize rapidly fluorescent Pseudomonas strains at the species level.