Abstract

A newly isolated Bacillus subtilis, as well as its antibiotic, had potent antagonistic activity against Erysiphe graminis f.sp tritici. Minimum inhibitory concentration (MIC) of the antibiotic for E. graminis f.sp tritici was determined. We arrived at an opinion: for some bacteria, unless the ammonium sulfate-precipitated substance had been filtered with a membrane, even if it had bio-activity in agar disc diffusion test, it is not necessarily true that such activity does come from the ammonium sulfate-precipitated substance.

Key word: Bacillus subtilis, Erysiphe graminis f.sp tritici, antibiotic.