Effects of formula fertilization on physiological and biochemical indexes and growth indexes of Isatis indigotica Fort

The content of soluble sugar was determined by anthrone colorimetric method，the soluble protein content by coomassie brilliant blue G-250 method，the superoxide dismutase（SOD）activity was determined by nitrogen blue four triazole photoreduction method，the POD activity was detemined by guaiacol method. L9（34）orthogonal design experiment in the field was used to，study the effects of formula fertilization on the physiological and biochemical indexes and growth indexes of Radix isatidis. Results shoued that treatment A9 was the best fertilization，the fertilization ratio was 9∶1∶8，compound fertilizer application amount was 1 125 kg/hm2，N，P，K application amount was 450 kg/hm2. Nitrogen fertilizer is beneficial to improve the yield of R. isatidis，organic manure and chemical fertilizer combination is more advantageous to improve the yield of R. isatidis.