氮肥追施时期对油菜产量、效益及氮素吸收利用的影响

摘要

为推荐双季稻区油菜合理施肥时期,以中熟偏早油菜品种"赣油杂5号"为试验材料,于2010~2011年通过大田试验研究氮肥不同追施时期对油菜产量、 效益及氮素吸收利用的影响.结果表明:不同追施时期条件下,N150处理下仅追施1次氮肥的平均株高要高于N180处理下仅追施1次氮肥的平均株高,而N150处理下追施2次氮肥的平均株高要低于N180处理下追施2次氮肥的平均株高;多次追施比一次性全部追施油菜籽粒含油量高.N150水平下各处理籽粒产量之间的差异均未达显著水平.在N180水平下,腊肥+薹肥追施时期处理与其他增施腊肥处理籽粒产量之间的差异未达显著水平外,与其他处理均达显著水平,腊肥+薹肥处理油菜籽粒产量最高,效益最好;苗肥+薹肥追施时期处理的氮肥利用率、氮肥农学利用率、氮素吸收效率都最高.此外,双季稻区油菜生产第一次氮肥追施可适当延后.%In order to provide a scientific nitrogen fertilizer topdressing period for rapeseed production in double-cropping rice area of southern China, the author carried out field experiments during 2010~2011 in Jiangxi province to study the effects of different nitrogen fertilizer topdressing periods on the yield , benefit and nitrogen absorption and utilization of early-middle-matu-ring rapeseed variety"Ganyouza No .5". The results showed that:under the condition of different topdressing periods , when nitro-gen fertilizer was topdressed for one time, the average plant height of rapeseed in the treatment N150 was higher than that in the treatment N180;while when nitrogen fertilizer was topdressed for two times , the average plant height of rapeseed in the treatment N150 was lower than that in the treatment N180 ;nitrogen fertilizer topdressing for many times could obtain higher oil content in rape-seed than that for one time.At the level of N180, the treatment of mid-December fertilizer plus stem-extending fertilizer obtained the highest oilseed yield and the best economic benefit , and the oilseed yield in this treatment was significantly higher than that in other treatments (except for the treatments of increasing the topdressing of mid-December fertilizer).The nitrogen use efficiency, agronomic nitrogen use efficiency, and nitrogen uptake efficiency of rapeseed in the treatment of applying seedling fertilizer+stem-extending fertilizer were the highest.The first-time nitrogen fertilizer topdressing for rapeseed production could be appropriately postponed in double-cropping rice area.