2023 Volume 92 Issue 4 Pages 300-304
This study was conducted to elucidate a suitable controlled release fertilizer and to develop a fertilizing style in which topdressing is limited to once for two-rowed barley for food. Two types of 15N-labeled linear type polymer-coated urea with different nitrogen elution periods (LP20 and LP30) were tested to elucidate the controlled release fertilizer effect suitable for a labor-saving fertilization method. We investigated the grain nitrogen content (GNC) and fertilizer nitrogen utilization rate (FNUR) of LP20 and LP30 at the full heading time and maturity stages in barley plants. At the full heading stage, GNC and FNUR were significantly higher in LP20 than in LP30. However, at the maturity stage, there was no difference between the two fertilizer types. Because the amount of nitrogen content at the full heading time affects the yield, it was judged that LP20 is suitable for the labor-saving fertilization of barley. Furthermore, the growth, yield, and suitability for the milling of barley via one-time topdressing system using LP20 were investigated. As a result, compared with the conventional plot, the maturity stage was one day later, the lodging index was the same, the yield was 5% higher, and the pealing aptitude was the same. Based on these findings, the applying mixed fertilizers composed of LP20 and fast-acting fertilizers at the tillering fertilizer application is a labor-saving fertilization method that can omit topdressing at the panicle formation stage.
