Respiratory activity of alginate-encapsulated Pseudomonas fluorescens cells introduced into soil

Alginate-entrapped cells of Pseudomonas fluorescens were introduced into soil microcosms to evaluate their respiratory activity (O2 consumption and CO2 evolution) and survival during a 14-day incubation period at 20 degrees C. Alginate-entrapped cells and cells resuspended in sterile distilled water and introduced into sterile soil exhibited relatively similar O2 consumption/CO2 evolution and survival over the 14-day period. The same treatments in non-sterile soil exhibited lower respiratory activity and a population density decrease of about 2.0 Log. cfu/g after 14 days. Alginate-entrapped bacterial cells may be a useful method for introducing genetically-engineered and non-engineered bacterial strains into the soil environment.