Abstract: A bacterial strain KJB04-11 with antagonistic effect against Fusarium oxysporum and Rhizoctonia solani was isolated from soybean rhizosphere. The strain was identified as Bacillus subtilis, based on its morphological, cultural, physiological, and biochemical characteristics, and 16S rDNA sequence analysis. The fermented filtrate with antagonistic activity showed certain thermostability and certain acidic and alkaline stability in the range of pH 1.0-13.0. The antagonistic active compositions in the fermented filtrate were purified by gel filtration on Sephadex G₂₅ column and RF-HPLC, and preliminarily identified as C16 mycosubtilin, C₁₇ mycosubtilin, and C₁₅ surfactin by infrared spectra, MALDI-TOF mass spectrum, amino acid composition analysis, and amplification of lipopeptide synthase gene. In field trial, the control efficacy of seed coating agent prepared with KJB04-11 against soybean root rot disease was 53.6%, and the soybean yield was increased by 12.5%

Key words: estuarine and coastal area, copepod, resting egg, diapause egg.