Studies On Fertilization Technology Of One-year-old And Two-year-old Sinocalycanthus Chinensis

The paper selected one-year-old and two-year-old Sinocalycanthus chinensis in pot as materials.Growth,physiology,photosynthetic indices,nutrient content,absorption and utilization of Sinocalycanthus chinensis were studied with different fertilizer rates,fertilization methods and formula fertilization to provide theoretical basis for the cultivation and management of Sinocalycanthus chinensis.The results were as follows:（1）An exponential fertilization trial on one-year-old Sinocalycanthus chinensis was conducted with five urea levels（setting a total of 0,300,600,900,1200mg·tree-1）.The results showed that with the increasing of N application rate,morphology indexes and chlorophyll content were improved;when the amount of nitrogen fertilizer reached a certain level,the morphological indicators tended to be stable,quality index and chlorophyll content decreased significantly. Within a certain range of N supply,the distribution ratio of N and K in roots and stems increased with the increasing of nitrogen application rate, the distribution ratio of leaves decreased;the distribution ratio of P in each organ was the opposite.And when applying urea level is 900 mg·tree-1,N,P,K nutrient content of seedlings was highest, nutrient absorption and utilization efficiency were the best. In a word,exponential fertilization of 600⁹00 mg·tree-1 urea levels were the most beneficial to seedlings growth,and 6⁷ month is the peak of seedlings growth, fertilization during this period was effective in promoting seedlings growth.（2）The effects on one-year-old Sinocalycanthus chinensis were studied with the mean fertilization,linear fertilization,exponential fertilization,half exponential fertilization,double exponential fertilization and non-fertilization methods.The results indicated that morphology, physiology, nutrient absorption and utilization efficiency of the exponential fertilization methods（EF, HEF treatment）were significantly higher than that of traditional fertilization methods（CF, ZF treatment）, and the indexes of double exponential fertilization method（DEF） were no significantly different with or less than that of traditional fertilization methods.Compared with traditional fertilization methods,the exponential fertilization methods could significantly increase the distribution ratio of N, P in roots and stems, and K in leaves.Under the same fertilizer rate, the effects of exponential fertilization methods were superior to the traditional fertilization ones, and applying 600¹200 mg·tree-1 urea levels once every two weeks could effectively promote the growth of seedlings.（3）The paper employed N, P, K three factors and three levels orthogonal trial to study one-year-old Sinocalycanthus chinensis growth and photosynthetic indices.The results showed that the optimal formula ratio of seedlings height was N₁P₃K₁,N₂P₁K₃ was best for ground diameter. N₁P₁K₃ was best for total biomass, the optimal combination of leaf morphology was N₁P₃K₃, N₁P₃K₃ was best for leaf SPAD values, the highest proportions of Pn,Ci,WUE were N₂P₃K₃,N₂P₁K₁,N₂P₃K₃. Considering the growth of seedlings and fertilization economy, N₁P₃K₃ was suitable for one-year-old Sinocalycanthus chinensis growth, namely urea, calcium superphosphate, potassium sulfate application rate being 0.3 g·tree-1, N:P:K=2:1:1.If economic conditions permit, nitrogen supply can be appropriately increased to make seedlings quality better.（4）N,P,K proportion fertilizer on two-year-old Sinocalycanthus chinensis trial results indicated that the optimal formula ratios of height, ground diameter were respectively N₂P₃K₃,N₁P2K2,N₁P₁K₃ was best for leaf length,width,area and biomass, N₂P2K₃ was best for leaf number,the optimal formula ratios of new and old leaves SPAD values were respectively N₂P₃K₁,N₂P₃K2;the best proportion of Pn was N₁P2K₃,and the peak appeared in June.In conclusion,the optimal formula ratio of two-year-old Sinocalycanthus chinensis wa s N₁P2K₃, namely when applying urea, calcium superphosphate, potassium sulfate content were 0.6g·tree-1,0.6g·tree-1 and 0.9g·tree-1,N:P:K=4:2:3,growth and photosynthetic indices of two-year-old Sinocalycanthus chinensis could be better.