三角形强化栽培模式下氮肥运筹对II优498产量及氮肥利用的影响

Effects of Nitrogen Fertilizer Management on Yield and Nitrogen Use Efficiency of Eryou 498 in Triangle-Planted System of Rice Intensification

以大穗型杂交籼稻II优498为材料,在三角形强化栽培(triangle-planted system of rice intensification,TSRI)适宜的密度和秧龄条件下,研究施氮量和施肥比例对TSRI结实期叶面积、光合作用以及干物质积累与转运的影响,并探讨花前期物质积累转运与花后期光合生产在产量形成过程中的作用,同时探索既能提高产量又能减少氮肥损失的氮肥运筹措施。结果显示,TSRI下,除蜡熟期叶面积指数(leaf area index,LAI)外,施氮量和施肥比例对光合作用和其他生育期的LAI有显著运筹作用;增施氮肥和氮肥后移可以显著提高齐穗期和蜡熟期剑叶净光合速率,LAI则随施氮量和氮肥后移程度增加多呈抛物线趋势。TSRI下施氮量和施肥比例共同提高,总颖花数和产量增加,而施氮量和施肥比例又各自通过提高千粒重和结实率来增加产量。TSRI下,花前干物质积累量、物质转运量、转运率与产量极显著正相关,施氮量为150kg hm-2,穗肥占总施氮量的30%的处理在显著增加花前干物质积累量和籽粒灌浆期间向穗部的转运量,实现高产的同时显著提高氮肥农学利用率和生理利用率,是TSRI平衡产量与氮肥利用率的最优氮肥运筹组合。

Hybrid rice Eryou 498 was used to investigate the effects of nitrogen （N） fertilizer management on leaf area, photosyn- thetic rate in productive phase, and also dry-matter accumulation and its transportation in triangle-planted system of rice intensifi- cation （TSRI） with appropriate seedling age and density. At the same time, the effects of dry-matter accumulation before anthesis and its transportation and dry-matter accumulation after anthesis on yield formation were also explored a N fertilizer management which could both increase yield and reduce the N waste. The results showed that in TSRI N fertilizer management had significant effects on leaf area index （LAI） and photosynthetic rate except the LAI in waxy ripening stage; with the increase of N rate and postponing N application, net photosynthetic rate in flag leaf in full heading stage and waxy ripe stage increased significantly; LAI in productive phase exhibited a parabola mostly with the increase of N rate and postponing N application. In TSRI, N rate and ratio of application both enlarged total glumes to increase yield. At the same time, N rate enlarged 1000-grain weight and ratio of application improved seed-setting rate to increase yield respectively. In TSRI, dry-matter accumulation before anthesis, dry-matter of transportation, and transportation rate of dry-matter had significantly positive correlation with yield respectively. The treatment which N rate was 150 kg ha-1 and panicle fertilizer was 30% of the whole N fertilizer enlarged dry-matter accumu- lation before anthesis and dry-matter of transportation significantly to reach maximum yield. It also improved N agronomy effi- ciency and N physiology efficiency significantly, so it was the best combination which could both increase yield and reduce the waste of N fertilizer to the maximum degree.