Effects Of Controlled-release Fertilizer Cemented And Coated With Nano-material On Crops

The effects of controlled-release fertilizer cemented or coated with nano-material were investigated and studied on seed germination, seedling growth, yield and qualities of wheat and corn, and nutrients of soil released in the soil column monitored in the leachate in this paper. All the above experiments were conducted in the screen house of Soil and Fertilizer Institute (SFI) and the Changping National Soil Fertility and Fertilizer Efficiency Inspection Station of China in Beijing from 2002 to 2004. The main results are as follows:1. The security of four kinds of cementing agents of CF2, Plastics-Starch, Clay-Polyester and humus acid-Polyester to emergence and growth of wheat seedlings assessed under the conditions of pot culture. These results indicated the fertilizers coated by the above four kinds of cementing agents had no inhibition effects on the emergence and growth of wheat seedlings.2. The differential dissolution rates of nitrogen of controlled-release fertilizers were lower than that of control, and the dissolution times of nitrogen of controlled-release fertilizers were longer than that of the control. In the soil column, the release rates and of nitrogen of controlled-release fertilizers were lower than that of the control, and the cumulated release rates were lower during certain time than that of the control. According to the length of lasting time of nitrogen releases, the above four controlled-release fertilizers were ranked as follows: fertilizer felted by plastics-starch > fertilizer felted by clay-polyester > fertilizer felted by humus acid-polyester > fertilizer felted by CF2.3. The nutrient release of controlled-release fertilizers could be characterized through the change of available N, P and K during the plant growth. After bulk blending controlled-release fertilizers (BBCRF) were applied in the soil, the concentrations of valid N and P in the soil reach two peaks at jointing the stage and heading stage of wheat. During these two stages wheat needed a great deal of nutrients. The trend of changes of available N, P in the soil from the felted controlled-release fertilizers (FCRF) was the same as that of BBCRF. However, the changes of available N, P in the soil from coated controlled-release fertilizers are lower in midterm and higher in late stage than that of the control.4. The effects of BBCRF and FCRF on some physiological characteristics, yields of wheat and corn were investigated, and the results showed that the application of BBCRF and FCRF increased the chlorophyll content in leaf, increased yields, raised the number of seeds per ear, the weight of seeds per ear, thousand seed weight, and reduced the number of sterile spikelet. 5. The application of BBCRF onwheat improved the nutritive and processing qualities of wheat. It increased the bulk density, protein content, thousand seed weight, total amino acid and essential amino acid, at the same time it increased content of wet gluten, sedimentation value, falling number of the wheat flour, total content of sugar, content of amylose and disaccharide.The application of BBCRF on corn increased content of crude fattiness, protein content, protein yield, content of total amino acid in corn seeds. The increase of content of total amino acid mainly relied on the increase of lysine, tryptophane, methionine, glycin, glutamic acid and aspartic acid. The application of BBCRF also increases the total content of free sugar, content of amylose, disaccharide, glucose, fluctose. However the influence of using BBCRF on corn crude starch is on the small side.6. The fertilizer felted by Plastics-starch was regarded to be the best, the fertilizer felted by Clay-Polyester was the second best by comparing the tested felted fertilizers from all aspects.