PLANT-GROWTH PROMOTING RHIZOBACTERIA - STRAIN IDENTIFICATION BY RESTRICTION-FRAGMENT-LENGTH-POLYMORPHISMS

A genomic library of the Pseudomonas putida strain GR12-2 was screened to identify both genus-universal and strain-specific 8-kilobase inserts. The genus-universal clone (pAM141), in combination with the restriction enzymes EcoRI, PstI, and PvuII, was used to generate unique restriction fragment length polymorphisms for 20 related plant growth promoting rhizobacteria and seven reference strains. Strain restriction fragment length polymorphism profiles based on the genus-universal clone pAM141 allow positive identification of individual pseudomonad strains. The strain-specific clone (pAM227) clearly distinguished the parent strain (GR12-2) from 16 other pseudomonad strains, including 8 P. putida, 7 P. fluorescens, and 1 P. cepacia. pAM227 may be useful for monitoring the fate of the P. putida strain GR12-2 in the environment.