Determination of Nitrogen Fertilizer Recommendation Rates Estimated by Soil-Testing for Different Types of Paddy Soils
2010
Moon, Y.H., Jeollabuk-do Agricultural Research and Extension Services, Iksan, Republic of Korea | Kwon, Y.R., Jeollabuk-do Agricultural Research and Extension Services, Iksan, Republic of Korea | Ahn, B.K., Jeollabuk-do Agricultural Research and Extension Services, Iksan, Republic of Korea | Lee, J.H., Chonbuk National University, Jeonju, Republic of Korea | Choi, D.C., Jeollabuk-do Agricultural Research and Extension Services, Iksan, Republic of Korea
To improve the existing nitrogen recommendation method based on chemical properties of soils and to establish new recommendation rates of nitrogen fertilizer due to different types of soils, the application rates of nitrogen fertilizer were examined in different soils of 12 experimental rice paddy fields. The application rates of nitrogen fertilizer estimated by soil-testing were higher than the rates of nitrogen standard recommendation that has been used. The application rates for minimum rice productivity ranged from a low of 168 kg/10a in sandy soil to a high of 315 kg/10a in saline soil. Amounts of nitrogen absorption in rice were proportional to the application amounts of nitrogen fertilizer in soils. Nitrogen use efficiency was the highest, 36.7%, in immatured paddy field and it was inversely proportional to the application amounts of nitrogen. the rice tasty value was the highest in the soils without nitrogen application, and also it was the lowest in the saline soils with or without nitrogen application. As comparing with the nitrogen application rates obtained by the existing nitrogen recommendation method, optimal nitrogen application rates estimated by the standardization of nitrogen application efficiency rate, environmental index, and rice quality were 1.0 fold in the well adapted soil and sandy soil fields, 0.92 fold in the immatured soil field, and 0.83 fold in the saline soil field.
显示更多 [+] 显示较少 [-]