不同施肥模式对水稻生理特性、产量及其N肥农学利用率的影响

EFFECTS OF DIFFERENT FERTILIZATION MODELS ON PHYSIOLOGICAL CHARACTERISTICS,YIELD AND AGRONOMIC NITROGEN USE EFFICIENCY IN RICE (Oryza sattva L.)

以水稻品种金优207为材料,对不施氮肥(T1)、试验区当地农民习惯氮肥用量(T2:尿素,纯N187.5 kg/hm2)和在农民习惯施氮量基础上减量配施氮肥(T3:氮减少20%,30%农民习惯用化肥+20%习惯用量的有机肥+30%习惯用量的缓释肥,纯N 150kg/hm2)3种施肥模式下水稻不同生育期的生理特性、产量及其N肥农学利用率进行了研究。结果表明:2个施氮处理间相比,T3处理的水稻产量较T2有所提高,农艺学性状更优,证明在农民习惯施氮水平上减施20%和20%有机替代及30%的缓释肥的施肥模式是可行的。T3减施氮肥使水稻氮肥农学利用效率提高了30.79%,植株各生育期的株高、分蘖数、叶面积指数、叶片SPAD值(叶绿素相对含量)与总生物量增加;单株的有效穗数、结实率、千粒重、理论产量以及实际产量也有所提高。说明只要合理配施,在保证产量的情况下氮肥用量还存在较大的减施空间。

In an attempt to reduce nitrogen application and improve yields in rice,different fertilization treatments,including control（no nitrogen fertilizer added,T1）,conventional fertilization level of local farmers（T2） and 20 percentage reduction in nitrogen fertilizer（30% conventional fertilizer of local farmers plus 20% organic manure and 30% slow release fertilizers,T3）,were conducted in this study.The effects of nitrogen reduction on the agricultural characteristics,grain yield and agronomic nitrogen use efficiency of rice were evaluated.The results indicated that T3 treatment tended to give higher yield and better agricultural characteristics of rice when compared with other treatments.These results demonstrated that the fertilization model of 20% reduction of conventional nitrogen fertilizer of local farmers,and combined with 20% organic manure and 30% slow release fertilizer is feasible on these planted fields.The agronomic nitrogen use efficiency of T3 treatment increased by 30.79% compared with T2 treatment.The plant height,tiller number,leaf area index,SPAD value（relative content of chlorophyll） and total dry weight of rice plants at each developmental stage were increased in T3 treatment,and the valid panicles per plant,seed setting rate,1000-grain weight,theoretical yield and actual yield were also elevated in T3 treatment.These results demonstrated that reasonable application of chemical fertilizer with organic manure and slow release fertilizer can enable reduction of the application of nitrogen fertilizers while maintaining crop yields.