麦秸还田与实地氮肥管理对水稻氮磷钾吸收利用的影响

粳稻品种扬粳9538种植于大田, 进行了麦秸还田与不还田、实地氮肥管理(SSNM)和农民习惯施肥法(FFP)等处理。结果表明, 在相同氮肥管理条件下, 与秸秆未还田相比, 秸秆还田后植株中N含量及N、P、K积累量在生育前期较低, P、K含量在整个生育期均较高; 秸秆还田提高了氮肥利用效率, 增加了N、P、K的收获指数。在秸秆还田量相同条件下, 与FFP相比, SSNM降低了N、P的吸收量, 提高了抽穗至成熟N、P、K的转运率, 增加了N和P收获指数。表明秸秆还田和SSNM可以提高水稻N、P、K的吸收利用效率。

Effects of Wheat-Residue Application and Site-Specific Nitrogen Management on Absorption and Utilization of Nitrogen, Phosphorus, and Potassium in Rice Plants

More than half of wheat residues are burnt or discarded for years in China, which not only wastes organic fertilizer source, but also pollutes the environment. Meanwhile, heavy use of nitrogen fertilizer has become a serious problem in rice production, especially in Jiangsu province. The purposes of this study were to investigate the effects of wheat straw application and site-specific nitrogen management (SSNM) on the absorption and utilization of nitrogen (N), phosphorous (P), and potassium (K) in rice plants. A mid-season japonica rice cultivar of Yangjing 9538 was field-grown. Three treatments of farmers’ N-fertilizer practice (FFP), SSNM based on chlorophyll measurement (SPAD) readings, no nitrogen application, and with or without wheat residue application (the straw was incorporated to soil) were conducted. The results showed that wheat-residue incorporation re-duced N content and the accumulations of N, P, and K in plants at the early growth stage, increased P and K contents in plants during the whole growth period, and increased nitrogen use efficiency, harvest index, and biomass production efficiency of N, P, and K when compared with the straw removal treatment. Under the same amount of straw incorporation, SSNM reduced the amount of N and P absorption in plants, and increased transportation percentage of N, P, and K from heading to maturity and N and P harvest index. There was no significant difference in the amount of K absorption between SSNM and FFP. The results indi-cated that both wheat-residue application and SSNM can increase absorption and use efficiency of N, P, and K in rice plants.