Study On Planting Saposhnikovia Divaricata(Turcz.) Schischk Fertilization Strategy In Western Jilin Province

Saposhnikovia divaricata（Turcz.）Schischk is a perennial herb of the genus Saposhnikovia in the umbelliaceae family.It is one of the major medicinal materials in northeast China.Due to the lack of basic research on fertilization technology and other related issues,there are many problems in the planting and cultivation of S.divaricata at present,such as blind application of various medicines and fertilizers,and lack of fertilization technology,which are severe challenges to the quality and yield of medicinal materials.In order to ensure the scientific and rational development of the planting industry of medicinal materials in the proper producing areas,drive pharmaceutical farmers to get rid of poverty and get rich,and explore the sustainable development approach that takes into account the safety of medicinal materials planting,resources and environment,this study took the natural distribution area of S.divaricata in Baicheng Pass of Jilin Province as the main experimental site,and carried out the research on the fertilization technology,such as the soil fertilizer supply capacity,the law of windbreak fertilizer demand,the combined application and reduction of chemical fertilizer and organic fertilizer.The main research results are as follows:1.The soil fertilizer supply capacity of S.divaricata site in Baicheng area was analyzed.The test results showed that the soil was alkaline,with high content of exchangeable base ions and low content of organic matter.The spatial distribution variation of nitrogen,phosphorus and potassium contents was large（coefficient of variation:49.86-126.85%）.Taking the soil fertility standard of the second National soil survey as reference,the proportion of soil organic matter content in all kinds of land that met the standard of the fifth level was 100%.The proportion of available nitrogen content meeting the standard of Grade 4 and Grade 5 was35.00%and 65.00%,respectively.The proportion of available phosphorus content in line with the standards of primary,secondary and tertiary places was 50.00%,45.00%and 5.00%,respectively.The proportion of available potassium content in line with the standards of primary,secondary and tertiary areas was 65.00%,10.00%and 25.00%,respectively,showing that the content of phosphorus and potassium was rich,but the content of organic matter and nitrogen was insufficient.Principal component analysis was used to comprehensively analyze the soil quality index（SQI）of S.divaricata site in the place.The results showed that the variation range of SQI was 0.27～0.52,mainly in the third and fourth grade sites.2.The growth dynamics and fertilizer requirements of different years of S.divaricata were analyzed.The results showed that 100-130 d and 410-490 d after seedling were the peak of dry matter accumulation in the first and second years,respectively.On 100 d and 440 d after emergence（mid to late August）,the accumulation of dry matter in the underground part of the first and second years of S.divaricata exceeded that in the above-ground part.Meanwhile,the content of N,P and K in S.divaricata increased rapidly,indicating that the growth center of S.divaricata shifted during this period,and N,P and K in the plants entered a vigorous accumulation period.From the perspective of fertilizer requirement,nitrogen,phosphorus and potassium requirement of annual S.divaricata showed the order of nitrogen>potassium>phosphorus.The fertilizer requirements were:N 230.68 kg/hm²,P₂O₅240.34kg/hm²,K₂O 257.90 kg/hm²;The demand of nitrogen,phosphorus and potassium for biennial S.divaricata showed nitrogen>potassium>phosphorus.The fertilizer requirements were:N484.05 kg/hm²,P₂O₅400.63 kg/hm²,K₂O 159.74 kg/hm².3.The effects of combined application of nitrogen,phosphorus and potassium on S.divaricata growth and soil quality were investigated by applying the application plan 3414recommended by the Ministry of Agriculture.The results showed that rational application of N,P and K fertilizer was beneficial to S.divaricata,increase yield and improve quality.Among them,N₂P₃K₂and N₂P₂K₂were the fertilization combinations with the highest yield and the best quality.The dependence of S.divaricata on nitrogen fertilizer was the highest,followed by potassium fertilizer and phosphate fertilizer.The optimal yield y=1463.16 kg/hm²was calculated by the yield frequency analysis method,and the recommended application rates of nitrogen fertilizer,phosphorus fertilizer and potassium fertilizer were 75.77～134.35 kg/hm²,176.56～377.79 kg/hm²,.73.49～140.97 kg/hm²,N:P₂O₅:K₂O=1:2.33～2.81:0.97-1.05.4.The effects of fertilizer reduction and organic fertilizer replacement on S.divaricata yield,quality and soil quality.Four quality indexes of medicinal material of all treatments were accorded with the quality level request in Chinese Pharmacopoeia 2020,and the application of biochar was helpful to improve the material quality.The results showed the yield of S.divaricata increase of 44.43%under the treatment YHT15,which was higher than organic fertilizer substitution fertilization model.CRITIC method analysis showed that fertilization treatments with high comprehensive scores were YHT15,YH30 and YH15.Soil quality under the two fertilization modes was higher than that under the control.The fertilization treatments with higher comprehensive scores of soil quality were YHT15,YHT30and YHT.The specific fertilization method suitable for S.divaricata planting in Baicheng area of western Jilin Province were as follows:The basic fertilizer was superphosphate 361kg/hm²+potassium sulfate 110 kg/hm²+organic fertilizer 82 kg/hm²+rice husk biochar 10000kg/hm²;Urea was applied to top fertilizer three times,respectively,with 29kg/hm²,29kg/hm²and 20kg/hm².5.The results showed that the dry weight of S.divaricata root increased by6.67%～145.33%after applying different kinds of organic fertilizers.The dry weight of S.divaricata root increased by 1.84g and the maximum of the pharmacopoeia component reached 0.79%under the treatment of organic chicken manure,which was 3.29 times higher than the standard of Chinese Pharmacopoeia;The application of different types of organic fertiliser significantly reduces soil bulk,increases soil porosity,improves soil fertility and increases soil enzyme activity to varying degrees.Considering the effects of yield,quality and soil,the combined application of chicken manure and chemical fertilizer can significantly improve the yield,quality and soil fertility of cultivated S.divaricata.