Study On Prescriptionfertilization And The Law Of Water Requirement Of Bupleurum Chinense DC

By means of potted experiment, field experiment, field investigation and indoor chemical analysis, using Bupleurum chinense DC., the characteristic of dry matter accumulation , the law of nitrogen, phosphorous and potassium absorption, accumulation, and distribution were studied. At the same time, the regression equation of the relationship between N, P, K or N, P, organic manure and the effects on the yield and quality were established. Meanwhile, the law of water requirement, the water consumption characteristic and the effects of N, P , water on Bupleurum chinense DC.growth and drought resistance were studied .It provided the scientific basis for standardized cultivation of Bupleurum chinense DC. to meet the need of GAP .The results as following: 1. Based on field investigation, the growth dynamic change of B. chinense DC. in central shannxi province was studied. The growth stages of two-year-old B. chinense DC. was ahead of that of one-year-old B. chinense DC., and the rapid growing period was two times of that of one-year-old B. chinense DC., with the result that there was different in dry matter accumulation.The shoot system and root system presented correlation of accelerating -each-other and restraining-each-other. In elongation stage, the root system grew rapidly while the dry matter of shoot increased rapidly. After blossom, enormous dry matter distributed to propagation organ, resulted in that the growth of root system was restrained. After seeds matured, the root system grew rapidly again. Based on the experiment data, the dry matter of root could be described as double S curve. 2. The absorption amounts of N, P and K were in the order of K>N>P under field condition. The climax , soil condition and yield had great effects on N, P and K absorption amount per 100kg dry matter of root .The experiment results showed, for one-year-old B. chinense DC., the average N, P and K absorption amount per 100kg dry matter of root were 11.79 kg, 2.42 kg, 14.11 kg respectively; for two-year-old B. chinense DC., the average N, P and K absorption amount per 100 kg dry matter root were 12.12 kg, 2.75 kg, 18.30 kg respectively. The ratio of N, P and K were differential in different growth stages. Take the example of potted experiment, the requirement for N was urgent in elongation stage in the first year, and the ratio of N:　P2O5: K2O was 12.26: 1: 9.90. The demand for P increased by first dormancy, the ratio of N: P2O5: K2O was 7.37: 1: 5.54. Of N, P and K, the ratio of N, K increased in the second year .The ratio of N: P2O5: K2O in elongation stage , flowering and fruiting ,mature phrase in the second year were 9.31: 1: 10.84, 12.74: 1: 11.22, 13.88: 1: 11.49 respectively. 3. The rule of absorption, accumulation and distribution of N, P and K was studied. For two-year-old B. chinense DC., of all organs, the order of percentage of N, P and K content were higher in flower (or seed ), followed by leaf, and then stalk and blanch and root before earlier November. However, after mid-November, the order of percentage of P content was seed > root >leaf >stalk and blanch, the order of percentage of K content was leaf >stalk and blanch>root >seed. Varying with the growth stages, the accumulation center of N, P and K changed gradually. Before elongation stage, the accumulation center of N, P and K was leaf, then became stalk and blanch gradually after elongation stage, eventually was propagation organ after blossom. According to the analysis of N, P and K content in B. chinense DC., at different growth stages, the total absorption amount of N, P and K were lower in the first year, while the percentage of content was higher, that was to say, the demand for N, P and K was urgent in the first year. The accumulation peak of N, P and K occurred regreening to later elongation stage in the second year. According to the evaluation of daily absorption of N, P and K quantity and uptaking intensity ratios, for two-year-old B. chinense DC. , N, P and K nutrient critical stage all came in regreening, the highest efficiency of N absorption was in middle of elongation stage, that of P was later elongation stage and K was in middle of flowering and fruiting stage. 4. The application of N, P and K fertilizer with rational ratio were beneficial to the growth of B. chinense DC. in each growth stages. However, the requirement amount and urgent degree for N, P and K were significantly different in every growth stages. In elongation stage in the first year, the over application of N, P and K fertilizer would result in restraining the growth of shoot and root, and decreasing the root-shoot ratio. Particularly, the over application of N fertilizer had harmful effect. The rational application of K fertilizer could increase the root-shoot ratio. From flowering and fruiting to dormancy in the first year, the requirement amounts for N, P and K were high, however, over and mere application of N fertilizer was harmful. In this stage, more P and K fertilizer and less N fertilizer could increase the root-shoot ratio. In elongation stage and flowering and fruiting in the second year, the requirement amount for N and P was higher and that of for K was relatively less. After flowering and fruiting, the rational application of N, P and K fertilizer had significantlypositive effects on root system growth, and suitable ratio of N, P and K could significantly heightened the root dry weight, what was more, large application of K fertilizer could heighten the growing rate of root. The result also showed that large application of P and K fertilizer could beneficial to the photosynthetic product distributing to root system and over application of N fertilizer showed negative effect . 5. According to the experiment result, the application of P and K fertilizer had negative influence on the absorption of N, P and K in B. chinense DC., and the more application, the more negative effect. Appropriate application of N fertilizer had positive effect on N absorption in plant and P absorption in shoot, but had negative effect on K absorption. Unsuitable application of fertilizer resulted in serious waste, and there was different among the apparent fertilizer use efficiency in different ratio N, P and K fertilizer. When one fertilizer was applied enormously and merely, the apparent fertilizer use efficiency was lower even negative number. However the apparent fertilizer use efficiency increased when two or three kinds of fertilizers were applied simultaneously. 6. For the experiment of N, P and organic manure, the model analysis showed that yield and content of Saikosaponin a were influenced greatly by N, P and organic manure, and the effects of nutrient elements on those two targets were in the order of N> organic manure > P. The high yield and high quality obtained under the condition of the reasonable combination and rational ratio of N, P and organic manure. According to these analysis, target yield and quality could be obtained with Urea rate of 173~268kg/hm2, Ca3(PO4)2 rate of 173~268 kg/hm2 and organic manure rate of 25470~52875 kg/hm2。According to mathematical model, the effect of NPK on yield was in the order of P>K>N, yield increased with the increase of fertilizer application amount, however, over application rate made yield decreased. The most suitable amount for targeted yield and Saikosaponin a content were Urea 167~246 kg/hm2, Ca3(PO4)2 451~529 kg/hm2, K2SO4224 ~2693kg/hm2. Based on the data obtained, N, P and K and organic manure could not heighten the content of essential oil, and unsuitable application of fertilizer decreased it. 7. Though field investigation, under this experiment condition, the application of N and K fertilizer improved the sensibility of B. chinense DC. to Root Rot Pathogen, while large application of P fertilizer could decrease the sensibility to Root Rot Pathogen.The fertilizer measure which could obtain highest yield and Saikosaponin a content could not decreased the sensibility. 8. It was studied that the effects of N and P nutrition on the drought resistance of B. chinense DC. under potted condition. The result showed that the water-holding power of the leaves was decreased by nitrogenous fertilizer,especially high nitrogenous level reducedmarkedly relative water content(RWC) of the leaves and strikingly dropped the cell membrane stability,restrained markedly the root growth.Nitrogenous fertilizer alleviated the reduction of Chlorophyll a/b ratio,resulting in the certain advance of photosynthesis, but in general nitrogenous improved the sensibility of B. chinense DC. to drought.Meanwhile,application of phosphorus fertilizer improved the cell membrane stability,advanced the root growth,kept the balance of water suction and water loss,and improved photosynthesis because of reducing the restraint of air pore,therefore B. chinense DC. maintained normal water metabolism to certain extent under soil drought condition and heightened its drought resistance. Meanwhile, it was studied that the law of physiological water requirement of B. chinense DC. under potted condition, and a proposition about irrigation and drainage was suggested on B. chinense DC. cultivation on shangzhou county in shannxi province. 9. Eventually, under the comprehensive consideration of growth rule, nutrient characteristic, the nature of fertilizer and local climax, soil condition, fertilizing Prescription and fertilizing technology about B. chinense DC.was suggested. Both fertilizing scheme and proposition about irrigation and drainage had been applied in standardized cultivation of Bupleurum chinense DC., and were used for formulating SOP of Bupleurum chinense DC.. KEY WORDS Bupleurum chinense DC., Prescriptionfertilization, Saikosaponin a,...