Indigenous microflora responses to introduction of cyanogenic strains of Pseudomonas fluorescens into soil.

The effects of cyanogenic Pseudomonas fluorescens strains introduced into soil on the kinetic of colony formation and bacterial community structure were investigated. About 7.8 x 10(8) and 1.2 x 10(9) cfu per g dry soil of TA1 and B2 were added to the soil portions, respectively. The parameters of colony formation by heterotrophic soil bacteria were determined. The bacterial community structure and phenotypic diversity were studied using concept of r/K strategies and echophysiological index, respectively. The physiological state of indigenous heterotrophic bacteria and gram-negative group did not change under the influence of the cyanogenic strains introduced. Phenotypic diversity of the soil bacteria also did not change significantly. However, some short-term shifts in community structure of indigenous heterotrophic bacteria were noticed. This study shows that the introduction of great numbers of cyanogenic P. fluorescens strains could be safely used as potential agents in biological control of soil-born pathogens.