Studies On Effects Of Nitrogen, Potassium, Chlorine Compound Fertilization Treatments On The Nitrate Content, Yield And Quality Of Chinese Cabbage

"311-A" optimal regression design was used to study the effect of nitrogen, potassium, chlorine compound fertilization treatments on the contents of nitrate, yield and quality of Chinese cabbage. And regression equation was founded by using computer software and worked out the optimum compose fertilization of planting Chinese cabbage with high yield and low nitrate accumulation. The result showed as follows:1. In a sertain area of chlorine concentration, chlorine can decrease the nitrate content significantly and promote the absorption of potassium and improve the quality of Chinese cabbage.2. It can improve the growth of leaves in low chlorine concentration and make Chinese cabbage suffer toxicity in high chlorine concentration.3. At zero nitrogen level,it can improve the growth of leaves and heading by increasing the potassium fertilizer.4. It can restrain the growth of leaves, highly accumulate the nitrate lOand decrease the quality in high nitrogen level.5. Regressive analysis showed that the optimum compose of the code of nitrogen, potassium, chlorine was 0.771, 0.892, -0.256. And convert to the fertilizer was 6.234g, 9.76 g, 261mg/L per plant. The validate test showed the nitrate content was 752.48mg/kg and the yield was 1.32kg a single plant in optimum compose fertilizatiom.