Nitrapyrin-ammonium combination induces rapid multiplication of mixed cultures of the stalked bacterium Nevskia ramosa famintzin and other heterotrophic bacteria

Nevskia ramosa, a bacterium that is very difficult to grow in artificial culture media in its recognizable and natural habit was induced to grow and multiply rapidly in mixed culture in an amended ASM medium. ASM liquid medium, an inorganic mineral medium, amended with 0.5 g ml^-1 of nitrapyrin and various levels of ammonium chloride (25–100 M) produced very significant enrichment of Nevskia ramosa within 24 h, permitting formation of its characteristic bushy dichotomously branched, stalked colonies with the bacterial cells at the apices of branches. ASM medium amended with either nitrapyrin or ammonium singly failed to produce growth of N. ramosa. The nitrapyrinammonium combination in ASM medium also produced a significant increase in growth of other heterotrophic bacteria. Our results should be of value to bacteriologists interested in studying N. ramosa, a species which has received little attention thus far.