Effect of nitrogen rates and method of nitrogen application on dry matter yield and some characters of sorghum-sudangrass hybrid

摘要

In this study, the effect of nitrogen (N) rates (0, 40, 80, 120, 160 and 200 kg N ha(-1)) and methods of N application (A(1): all N at sowing; A(2): no N at sowing, half N after the first cutting and the remaining half after the second cutting; A(3): one-third N at sowing, one-third after the first cutting, and the last third after the second cutting) on dry matter (DM) yield and some characters of the sorghum-sudangrass hybrid was investigated. DM yield increased significantly from 27.0 g pot(-1) (0 kg N ha(-1)) to 38.6 g pot(-1) (120 kg N ha(-1)). Higher N rates continued to increase the number of tillers per plant(-1) (except for 40 and 80 kg N ha(-1)). N rates have significant effect on crude protein (CP) content, and CP content varied from 6.71 to 7.08%. N up to 120 kg N ha(-1) rate increased CP yield, but no difference was observed among 80, 120, 160 and 200 kg N ha(-1). There was no significant effect of the method of N application in terms of DM yield, tillering and CP yield. However, the method of N application had a significant effect on CP content, which was 7.09% by A(1), 6.97% by A(2) and 6.57% by A(3).