| Fertilizer research is being focused on slow/controlled release fertilizer (SRF) which have high nutrient use rate and low environment pollution now. The need of mulriple nutrient for plant couldn't be satisfied by single nitrogen nutrient from slow release fertilizer, so it wasn't applied extensively in agricultural crops because of high price. Slow/controlled release fertilizer were mainly used in the economical crops and used scarlely in medicine plant such as Coptis as traditional Chinese medicine in China. Including, it is important for modern agriculture to develop non-coated and mulriple nutrient fertilizers.Lab constant incubation, field experiment and chemical analysis methods were adopted to study the dynamical characteristic of nitrogen, phosphorus and potassium nutrient release in different mediums (pure water, sand and soil) and temperature conditions (30℃ and 20℃ ), and to comment yield and medical quality- of Coptis in 5 years by using slow release fertilizers. The objectives of this study were to select proper special fertilizers of Coptis and to provide scientific evidence for modern Coptis cultivation.The anti-soluble period of 5 SRFs in the pure water was more than 48 hours at 25℃. The period of SRFs was over 90 days according to formula "x ±水(d)=(h)×2.34" . The discrimination of nutrient solution was big in prior to incubation, but small in latter of incubation. And the slow release characteristic of nitrogen and phosphorus of SRF4 was the best among the SRFs.The period of nitrogen, phosphorus and potassium release ranged from 10 to 28 days in sand incubation. With the time prolonging, the relative release rate of nutrient in all SRFs became smaller than that of latter of incubation. The nutrient relative 'release rate of SRFs showed that the nitrogen of SRFi and phosphorus and potassium of SRFyreleased slowly.The nitrogen and potassium release accumulated amount of all SRFs in neutral soil was larger than that of acidic soil, especially at 20℃. The nitrogen accumulated amount of all SRFs in neutral soil ranged from 40 to 450 mg/10g, which increased 50% than that of acidic soil. The potassium of all SRFs ranged from 50 to 400 mg/10g in neutral soil. The difference of phosphorus accumulated amount release among all SRFs (except SRF4> in neutral soil was bigger than that of acidic soil, which was not obvious at 30℃.The Elovich equation, double constant equation and parabola equation were applied todescribe the dynamical process of nutrient release in SRFs. Elovich equation made a match best among three equations. The parameter b of each equation could be used to reflect the nutrient release rate. The b value of equations in neutral soil was bigger than that of acidic soil at the same temperature condition and the b value of equations at 30℃ was larger than that of 20℃ at the same soil condition. The change of b value between same nutrient fertilizers accorded with the accumulated amount of nutrient release. The order of b value in equations was K>P>N in neutral soil and K>N(P)in acidic soil.The nutrient relative release rate of SRFs was various under different soil and temperature condition. At the same temperature, the nutrient relative release rate of SRFs in neutral soil was bigger than that of acidic soil. There was more difference in the relative release rate of phosphorus and potassium than that of nitrogen in different temperature and soil.The biomass of Coptis in l~5years (except SRF4 at the 2nd year and SRFa at the 5th year) was increased by 1.57-12.6% for applying 4 SRFs. The maximum Coptis biomass in 1-5 years appeared at SRFa, SRFi, SRFa, SRF4and SRF| treatments respectively. The yield of Coptis in 5 years was increased significantly or great significantly for applying 4 SRFs.The content of nitrogen and phosphorus in Coptis were increased with its growth period, which was the highest in the third year or the fourth year and the content of potassium came up to be the highest in the fifth year among 5 years. And the nutrient content of Coptis in st...
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