The Effect Of Ratio Nitrogen, Phosphorus And Potassium Fertilizer On Yield And Quality Of Rehmannia Glutinosa F.hueichingensis

This study chooses the variety85-5 Henan authentic herbs Rehmannia Rehmannia[Rehmannia glutinosa f. hueichingensis (Chan et Sehih) Hsiao]as material, ,does the research into the impact of the law of growth and development about Rehmannia as well as the different ratios of nitrogen, phosphorus and potassium fertilizers upon its yield and qualities, and conducts the study in detail that differences made by the different ratios of nitrogen, phosphorus and potassium fertilizers in bio-agronomic traits, such as the height of Rehmannia, the width of crown, the area of leaf, the length of root, the diameter of root and so forth, as well as yield, content of active ingredient through exerting the method of field experiment in the original land . Then according to the result of research selects. All the above is to lay the foundation for taking the measure of future high-yield cultivation technique. Conclusions of the study are as follows:1. The individual growth and development of Rehmannia can be divided into four periods which are seedling period,main root stretch period,root expansion period and the harvest period.2. In a certain range, the height of Rehmannia, the width of crown, the area of leaf will be larger than before as the increase of the amount of nitrogen, phosphate, potash fertilizer; In a certain range, the length of root and the diameter of root also will be larger than before as the increase of the amount of nitrogen, phosphate, potash fertilizer, but they will reduce if the fertilizers are excessive.3. In a certain range, the fresh weight, dry weight and the discount rate of the parts of Rehmannia on the ground will increase as the increase of the amount of nitrogen, phosphate, potash fertilizer. In a certain range, the fresh weight, dry weight and the discount rate of root of Rehmannia on the ground will increase as the increase of the amount of nitrogen, phosphate, potash fertilizer, but it will reduce yield if the fertilizers are excessive. 4. Under different fertilizer ratios the differences in the content polysaccharide in the root of Rehmannia are at extremely significant level. N1P2K2 is the highest, reaching 11.64 percent; N0P0K0 is the lowest, only 4.48%. Under different fertilizer ratios the differences in the content of Catalpol in the root tuber of Rehmannia are at extremely significant level. N1P1K1 is the highest, reaching 8.48 percent, and N0P0K0 is minimum, only 4.26%.5. Under different fertilizer ratios the differences in yield of fresh weight of Rehmannia per mu are at harvest differences extremely significant level. N1P1K1 is the highest, reaching3487.94kg / mu and N0P0K0 is the lowest ,only 2135.67 kg / mu. The treatment of N1P1K1 is much better than other treatments.Therefore, through this research, the best combination of fertilizer ratio is N1P1K1, that is, N 15kg/667m2, P2O5 8 kg/667m2, K2O 12 kg/667m2.