麦秸全量还田下氮肥运筹对水稻产量及其产量构成的影响

Effects of nitrogen application on the yield and yield components of rice under total wheat straw returning

在江苏沿江地区,研究了"麦一稻"两熟制稻田麦秸全量还田下,氮肥运筹对水稻产量及其产量构成的影响。结果表明:在基肥40%、分蘖肥20%、穗肥40%的施N比例下,麦秸全量还田的水稻产量及其产量构成因素相关指标均随施N量增加表现出先增加后降低的趋势,但各指标达到最高值时的N用量有所差异,高产水稻N用量范围为286.78—427.83 kg/hm^2,在此范围内降低施N量能够实现节氮增效;水稻施N量300 kg/hm^2时,随着穗肥施N比例(20%—50%)提高,其单位面积穗数增多,单穗颖花数和单穗实粒数减少,麦秸全量还田下以基肥40%、分蘖肥30%、穗肥30%的施N比例,其穗粒结构较为协调,单位面积产量最高。

The effects of nitrogen application on the yield and yield components of rice under wheat-rice rotation system with total wheat straw returning were studied in the regions along Yangtze River in Jiangsu.The results showed that the yields and yield components of rice increased at first and then decreased with N application rate increasing under the ratio of 40%basal fertilizer,20%tiller fertilizer and 40%panicle fertilizer,but the amount of N was different when the index reached the highest value.High yield of rice was obtained in the nitrogen application rang 286.78—427.83 kg/hm2,in this range,the nitrogen amount could be reduced to improve the nitrogen efficiency.Under the nitrogen application level 300 kg/hm2,panicle number increased,while spikelet number per panicle and grain number per panicle decreased,with the increase of N ratio（20%—50%） of panicle fertilizer application.The panicle-grain structure was more coordinated,and the yield per unit area was the highest with 40%basal fertilizer,30%tiller fertilizer and 30%panicle fertilizer under total wheat straw returning.