The Research Of Seeds Germination And Fertilization Techniques Of Platycodon Grandiflorum

The characteristics of seeds germination, growth and fertilizer requirement of Platycodon grandiflorum (Jacq) A.DC were studied in the experiment.The effects of different temperatures, the germination bed and reagent on seeds germination (Platycodon grandiflorum) were discussed to find the optimal conditions for seed germination of Platycodon grandiflorum. Poikilothermic treatments (25/15℃) promoted seeds germination. The seeds germination percentage, germinating potential and germination index of Platycodon grandiflorum cultivated in the vermiculite were higher than those cultivated in the soil, river sand and filter paper. 100 mg·L^-1 GA3and200 mg·L^-1 PEG 6000treatments can significantly improve the seeds germination percentage,germinating potential and germination index of Platycodon grandiflorum.The effects of nitrogen and phosphorus fertilization on the growth of Platycodon grandiflorum were studied in pot experiment by means of measuring the root and stem nitrogen and phosphorus content, agronomic traits, quality at harvest and other indexes.In order to find the optimum formula program of nitrogen and phosphorus fertilizer for Platycodon grandiflorum growth, the effects of fertilization on growth and active ingredient accumulation of Platycodon grandiflorum were discussed.At harvest,root length and root diameter with the treatment of nitrogen (0.3g·kg^-1soil)+P2O5(0.2789g·kg^-1soil) were respectively 37.56% and 27.55% higher than those N0P0 treatments, while the biomass yield,economic yield, proteincontent and total saponin content were respectively 60.58%, 74.52%, 64.05% and 27.07% higher than thoseN0P0 treatments. In pot experiment, nitrogen (0.3g kg^-1 soil)+P2O5(0.2789g·kg^-1soil)was the optimum amount of fertilization by considering factors, such as the growth, economic yield and active ingredient, and the growth effect was obvious for Platycodon grandiflorum.In the field experiment,effects of different fertilization levels on height,root length, fresh weight and dry weight in different growth periods, agronomic traits, yield and quality at harvest were studied.The growth indexes in have advantages over N0P0K0 and other fertilization program. At harvest, there were significant differences (P <0.05) between N3P1K3 treatment other fertilization treatments in biological yield, grain yield, soluble sugar and total saponin content respectively 95.65%, 140.80%,122.19% and 147.62% higher than N0P0K0 treatment,so nitrogen (225 kg·hm^-2)+ P2O5(53.16kg·hm^-2)+ K2O(225kg·hm)was the optimum amount of fertilization for growth of Platycodon grandiflorum considering growth and economic effect in this study. The optimum amount of fertilization under the actual filed conditions not only saves resource and time, but also reduces environmental pollution. At the same time,economic yield and the active ingredient content were significantly increased,and it promotes in the field.