Effects Of Different Potassium Fertilizers On Seed Germination And Seedling Growth Of Three Crops

Fertilizer is the largest investment in farmers’ investment in production.Fertilizeris the main factor for the harvest of crops，approximately accounting for40-60%. Andpotassium fertilizer has a very important role in growth of crop seedling. Currently,there are several kind of potassium fertilizer in the market, mainly includingpotassium chloride, potassium sulfate and potassium nitrate. Because application ofpotassium nitrate leads to withering readily and the price of potassium sulfate isexpensive, famers much prefer to apply potassium chloride. Chlorine is one of theseven necessary trace elements for crop growth, but large concentration of chlorinecan result in withering of plant. The seedling stages of different plants have varioustolerance to chlorine and critical tolerance concentration of chlorine. In the presentexperiment, controlled-release potassium chloride coated by the technology ofFluidized bed envelope was used for germination test of seed and growth test ofseedling concerning wheat, peanut, and cotton. Meanwhile, we compared thisfertilizer efficiency with ordinary potassium chloride, potassium sulfate andpotassium nitrate and evaluate the effect of different types of potassium fertilizer ongermination of seed and growth of seedling. The above mentioned research contenthad been analyzed and studied in order to provide scientific basis for reasonableapplication of fertilizer and management of seedling stage involving wheat, peanut,and cotton. The main results were as follows:1.The potassium release of coated potassium chloride fertilizer in still water（25℃） was "parabolic" shape. At the beginning it released faster and moreevenly.With time, the release rate tends to slowly andsmoothly.Coated controlled release of potassium chloride was9.75%within24h， nomore than75%in28d.The release of nutrients was able to meet the need of rapidgrowth of crop.2. The result of GB／T35434—1995indicated the suitable chlorineconcentrations for germination of wheat seed （Jimai22） and peanut seed （Huayu22）were in the range of0to80mmol/L and40to120mmol/L respectively. 3.Compared with ordinary potassium chloride of the same application rate, theplant dry weight and chlorophyll content were higher when controlled-releasepotassium chloride were applied. The application of controlled-release potassiumchloride was more effective in improving chemical properties of soil and growth ofplant. controlled-release potassium chloride.The fertilizer efficiencies ofcontrolled-release potassium chloride, ordinary potassium sulfate and potassiumnitrate were similar during the stage of seedling of wheat and peanut.4.The dry biomass of cotton was not significantly influenced by high amount ofcontrolled-release potassium chloride application. However, when larger amounts ofordinary potassium chloride and potassium sulfate were applied, e.g.0.12g K₂O/kgsoil, the growth potential of plant were poor. At a given K₂O content (0.12、0.16、0.20g·kg^-1), significant differences were observed between the treatments ofcontrolled-release potassium chloride and ordinary potassium chloride.5.Compared with ordinary potassium chloride, controlled-release potassiumchloride was more effective in improving the germination rate and growth of cotton.While the difference between the treatment of potassium chloride and potassiumchloride was not significant.