Abstract:

Excessive nitrate content in vegetables is a threat to human health. How to decrease nitrate content in vegetables is a very important issue for human. The effect of Paenibacillus polymyxa on nitrate content in rape was researched in this study. The conclusion showed that P. polymyxa could obviously decrease nitrate content in rapes, when nitrate content was high after exerting urea in soil and the content was higher than the state standard (3000 mg/kg). The nitrate content was similar after exerting P. polymyxa fermentation liquor to the contrast with no exerting urea in soil. This effect was disappeared after the P. polymyxa fermentation liquor was heat-inactivated. Density of P. polymyxa fermentation liquor (3×105 CFU/mL to 3×107 CFU/mL) could obviously decrease nitrate content in rapes. When the concentration of P. polymyxa fermentation liquor was increased, the effect of decreasing nitrate content in rapes was more obvious.