STIMULATION OF SYMBIOSIS AND GROWTH OF LUCERNE BY COMBINED INOCULATION WITH RHIZOBIUM-MELILOTI AND PSEUDOMONAS-FLUORESCENS

Combined inoculation of the strains Rhizobium meliloti mel 8 and Pseudomonas fluorescens PsIA12 to lucerne stimulated the development of young plants more than a single inoculation with Rhizobium. In field experiment about 2 years on Albic luvisol soil the mixed inoculants enhanced the yields of dry matter and raw protein and the uptake of phosphorus and potassium in shoots. As mechanisms of synergistic co-inoculation effects were observed increases in root surface area and stimulation of nodulation and nitrogenase activity in early stage of plant development. In addition there was a high significant increase in the activity of uptake hydrogenase in 10(7) mixed bacterial cells under ex planta conditions. The co-inoculation of both bacterial strains has effected the native microbial population in rhizosphere.