Effects Of Mineral Nutrients On Growth And Effective Ingredient Accumulation Of Isatis Indigotica Fort

Isatis Indigotica Fort, is a common medical plant. Effects of mineral nutrients on the growth and effective ingredient accumulation of isatis indigotica were investigated by means of potted experiment and field experiment and chemical analysis. The results are as following:1. N fertilization showed obvious positive effects on the shoot height, single leaf area, Chlorophyll, and dry matter accumulation. The content of soluble protein was increased after application of N and P fertilizers. R/S ratios was decreased when N fertilizer applied alone, and increased after P applied. The best performance was the sixth treatment in the treatment of mixed application.2. The peak period of shoot growth of isatis indigotica appeared in the first ten days of July, then root (woad) growth becomes fast untill September. The peak period of root growth is later than isatis indigotica, and the content of effective ingredients discreased until growth is steady or stops increase (September-October).and then the content of effective ingredients increase and reachs maximum. Isatis indigotica should generally be harvested in July and September, when it contains highest content of indigotin and indirubin.Wheres the woad should be harvested in October because maximum content of indigotin in woad appeared in middle July and early October and indirubin happended in early October. Based on the integrated analysis of yield and content of the effective ingredients, the woad should be harvested in October.3. In the experiments of N, P, K and organic manure application, the model analysis showed that yield was influenced greatly by N, P, K and organic manure, and the effects of nutrient elements was in the order of organic manure >K > P>N, the indigotin content was also influenced greatly by N, P,K and organic manure and the order is K>N>Organic manure>P, the indirubin content in the order of K>P>N> Organic manure. The high yield and high quality obtained under the condition of the reasonable combination and rational ratio of N, P, K and organic manure. According to mathematical model, target yield and quality could be obtained with N rate of 22.12-2.42g N /pot, 1.39-1.69gP₂O₅/pot, 1.98-2.29gK₂O/potand 1.57-1.87g organic manure/pot.4. In pot experiment chlorophyll content of isatis indigotica was increased greatly by spraying Fe and Zn during the vegetative growth stage. The contents of Fe, Mn, Cu and Zn in the isatis indigotica are increasing with growth stages and the spraying time. The contents of Fe and Mn in isatis indigotica are increased greatly by spraying Fe and Mn compared with control. The accumulation of indigotin in indigotica and woad was promoted by spraying Fe, Mn, Zn and the influence order of the isatis indigotica is Zn>Fe>Mn, but woad order is Fe > Mn > Zn. The accumulation of indigotin in isatis indigotica and woad was restrained by spraying Cu. The indirubin content in isatis indigotica and woad are increased by spraying Fe and Mn.The indirubin content in isatis indigotica and woad are discreased by spraying Zn and Mn.