| Filtered and identified certain bacteria which can degradate chlorimuron-ethyl efficiently, factors concerning degradation efficiency was studied.Through enrichment culture and separation two chlorimuron-ethyl highly effective degrading bacterias were isolated from soil of long term applied with chlorimuron-ethyl, named B1 and B2.The two bacterias could use chlorimuron-ethyl as sole carbon source,and chlorimuron-ethyl degrading rate respectively was 80%and 86%within 96 h at maiyazhi containing 10 mg/L chlorimuron-ethyl.It was identified as Bacillus subtilis by shape observing, biochemical and physiological characters analysis,and 16SrDNA sequence analysis.It was named as B1 16SrDNA sequence suggested that it has 1511 bp,and the content of G and C is 55.13%.The number in GenBank is DQ401073.1.It was identified as Ochrobactrum anthropi by shape observing,biochemical and physiological characters analysis,and 16SrDNA sequence analysis.It was named as B2 16SrDNA sequence suggested that it has 1490 bp,and the content of G and C is 54.97%.The number in GenBank is AM114410.The research result of factors concerning degradation efficiency indicated that the favorable environment of B1 were temperature 35～37℃,pH6～7,optimum volume of medium was 50 ml·250 mL-1.In synthetic medium and pure culture,about 80%chlorimuron-ethyl was degraded in a Maiyazhi medium containing 10 mg·L-1chlorimuron-ethyl under the condition of 37℃,120 r·min-1and 96 h.The favorable environment of B2 were temperature 35～37℃, pH6～7,optimum volume of medium was 50 ml·250mL-1.In synthetic medium and pure culture, about 86%chlorimuron-ethyl was degraded in a Maiyazhi medium containing 10 mg·L-1 chlorimuron-ethyl under the condition of 37℃,120 r·min-1and 96 h. |
