Effects of Nitrogen Fertilizer on Nitrate Accumulation and Reductase Activity of Chinese Cabbage

A Chinese cabbage variety(605) was tested under different nitrogen application amount to study the effects on its biomass,nitrate content and nitrate reductase activity and to provide a theoretical reference for production of pollution-free vegetable.The results showed that the biomass,nitrate content and nitrate reductase activity increase with increment of nitrogen application amount,and the biomass decreases and nitrate content increases by a large margin when nitrogen application amount is 0.3 g/pot.The optimum nitrogen application amount is 22.5 kg/667m2 in production of pollution-free vegetable.