Screening and Application of Denitrifying Bacterium

6 bacterium strains of highly denitrifying capability were screened from Tianjin garden soils.They could decrease 30% ～ 80% nitrate concentration in citrate culture medium.Especially the strain of F1401 had the best effect in the six strains.Denitrifying capability of F1401 in the farmland irrigation water was determined.The results showed that the denitrifying rates increased with in-oculated amount increasing under the condition of standing,and 2 mL fluid was the best to the nitrate concentration of 150 mg/kg.