氮肥运筹对机插双季晚粳稻产量和氮肥利用率的影响

考察氮肥运筹对机械插秧双季晚粳产量和氮肥利用率的影响。结果表明,T3(基肥、蘖肥和穗肥比例为5∶3∶2)有效穗数最高,实际产量也最高,达到599.5 kg/667 m~2,较T1(仅施基蘖肥)产量增加13.2%。随穗肥比例增加,水稻产量、生物量积累量和氮肥利用率均呈现先增后减的趋势,而茎鞘物质输出率(EPMSS)和转换率(TPMSS)逐渐减少。施氮处理齐穗后5 d灌浆速率均低于CK(不施氮),而后灌浆速率逐渐高于CK。总之,适当氮肥后移有利于提高水稻有效穗数、产量和氮肥利用率;氮肥在基肥、蘖肥和穗肥比例为5∶3∶2是机插双季晚粳最佳施氮模式。

Effect of Nitrogen Application to Yield Development and Nitrogen Fertilizer Efficiency of Machine-transplanted Late Japonica Rice in Double-Season Rice System

The research on the influence of the nitrogen application to yield and nitrogen efficiency of late japonica rice in double season cropping system with machine-transplanted seedling. The results showed that the T3(basal fertilizer, tiller fertil-izer and panicle fertilizer proportion 5:3:2) as the highest effective panicles,actual yield was the highest,up to 599.5 kg/667 m2, and the T1 (only basal and tiller fertilizer) production increased by 13.2%. With the increase of panicle fertilizer proportion, the rice yield, biomass accumulation and agronomy utilization efficiency of nitrogen all showed a trend of first increasing after decreases, and photosynthetic material transfer rate(EPMSS) and conversion rate(TPMSS) gradually reduced. Full panicle ni-trogen processing after 5 d grouting rate were lower than that of CK(no nitrogen fertilizer applied), and then gradually higher than that of CK. Therefore, appropriate nitrogen back to improve the effective panicles of rice, yield and nitrogen utilization efficiency. The best mode of nitrogen application was that of basal fertilizer, tiller fertilizer and panicle fertilizer proportion 5:3:2 for late japonica in double season cropping system with machinery-transplanted seedling.