COLONIZATION OF GERMINATING TOMATO SEEDS WITH THE PLANT GROWTH-PROMOTING RHIZOBACTERIA, PSEUDOMONAS-FLUORESCENS 5.014 AND ITS MUTANT 5-2 4/

In the present study the colonization pattern of Pseudomonas fluoresce ns, strain 5.014 and its mutant 5-2/4 with reinforced 2,4-diacetylphlo roglucinol production, added to tomato seeds was investigated. The col onization of the roots and seeds was monitored during germination. Als o, the effect of bacterization on the initial root development was exa mined. The wild strain 5.014, and its mutant 5-2/4, extensively coloni zed the seeds and roots during the germination phase. The added strain s were distributed over the entire root and the distal segment was den sely colonized compared to the proximal and the middle segment. When t he strains were inoculated in a 1 : 1 suspension the mutant suppressed growth of the wild strain. The indigenous seed flora showed a large v ariation in density. Application of plant growth-promoting rhizobacter ia, however, resulted in a stabilization of the bacterial density on t he seeds and roots. The inoculated roots were more compact to the untr eated control roots.