[Objective] Effects of controlled release N fertilizers on wheat growth and yield were studied to provide reference for the application of controlled release fertilizers on wheat. [Method] A field experiment was conducted to study the effects of different types and levels of controlled release N fertilizers on the growth and yield of wheat. In this experiment, a treatment with the application of common urea and potassium chloride（common fertilizer） was established, and treatments with controlled release N fertilizers A and B with different coating materials were also established. [Result] The results showed that under the condition of the same P and K levels, controlled release N fertilizer A at a proportion of 100%, controlled release N fertilizer A at a proportion of 80% and controlled release N fertilizer B at a proportion of 80% could promote wheat growth, optimize yield components, and increase the amount of dry matter accumulation and grain yield. [Conclusion] One-time application of controlled release N fertilizer could be adopted in wheat production to achieve the purposes of saving fertilizer, saving labor and increasing efficiency.
[Objective] The aim was to study the release characteristics of different release-controlled fertilizers, as well as their effects on wheat growth and develop- ment under water stress. [method] With phosphorus-potassium fertilization and opti- mized fertilization （OPT） as the control, the release characteristics of 4 kinds of re- lease-controlled nitrogen fertilizers （A, B, C and D） coated with different materials were studied. [Result] Under the same phosphorus and potassium levels, the re- lease-controlled nitrogen fertilizers A and B significantly improved the yield of wheat. Spike number is the main reason leading to the difference in yield. The fertilizers A and B were released by 44.4% and 46.3% before winter, released by 72.1% and 69.8% at the jointing stage, and related by 88.0% and 91.5% in the harvest period, meeting the nitrogen requirement of dryland wheat across the growth period. Com- pared with OPT, the nitrogen accumulation amounts in treatments A and B were increased by 1.39 and 2.09 kg/667 m2, the nitrogen use efficiencies were increased by 8.66% and 13.04%, and the nitrogen partial factor productivities were increased by 9.00 and 7.22 kg/kg, respectively. [Conclusion] Among the 4 kinds of fertilizers, A and B were considered as the optimum release-controlled nitrogen fertilizers for winter wheat on dry land.
