不同氮水平对桂中地区晚稻生长性状与产量的影响

为探讨桂中双季稻区的水稻氮肥施用效应,为当地水稻生产合理施用氮肥提供理论依据;2008—2009年在广西来宾市兴宾区进行了氮水平对早稻生长性状、产量以及氮肥农学效率影响的大田试验研究。结果表明,施氮对桂中稻区晚稻的生长发育具有促进作用,能明显地改善水稻的产量结构,提高水稻产量。与不施氮相比,2年晚稻施氮处理的株高与有效穗分别平均提高10.33%、37.18%,单穗总粒数与千粒重分别平均提高17.06%、7.17%,产量平均提高37.00%。但当氮肥施用量>325.5kg/hm2时,随着氮肥的继续施用,晚稻氮肥农学效率大幅度降低,农业成本增加,环境污染严重。可见,在桂中稻区早稻施氮163.5～325.5kg/hm2时,既能稳定水稻高产,确保当地粮食安全,又能保证肥料资源得到高效利用,是桂中地区晚稻一个比较合理的施肥水平。

Effect of Different of N Fertilization on Agronomic Traits and Yield of Late Rice in Middle Area of Guangxi

In order to investigate the effect of nitrogenous fertilization in double cropping rice of Middle Area of Guangxi,to growth character of rice,yield and agronomic efficiency of nitrogen,we carried out field experiment for effect of different of nitrogen on rice in Xingbin county of Guangxi in 2008—2009.Results show that the nitrogen has simulative effect for early rice growth,obviously improve yield structure of rice,raise rice production,compared with no nitrogen(N0),plant height and effective panicles of two years lately rice of nitrogen treatment increased respectively 10.33% and 37.18%,total grain number of single panicles and setting rate increased respectively 17.06%and 7.17%,average of rice yield increase 37.00%.But when nitrogen>325.5 kg/hm2,rice nitrogen efficiency is reduced substantially,raised agricultural cost,polluted seriously environmental with continue to increase of fertilizer.Visible,late rice nitrogen was applied nitrogen 163.5～325.5 kg/hm2 that is a more reasonable fertilization pattern in Middle Area of Guangxi,because it can both stabilize high-yielding of rice,ensure security of local food and assure high utilization of the fertilizer resources.