中文摘要：

【目的】探讨麦秸秆还田与施氮技术对直播水稻产量、品质的影响及氮肥利用效率的表现。【方法】以直播粳稻扬粳9538为材料进行大田对比试验，设置麦秸还田与不还田、实地氮肥管理（SSNM）和农民习惯施肥法（FFP）等处理，测定水稻产量、品质及氮肥利用效率。【结果】无论是SSNM还是FFP，与秸秆未还田相比，秸秆还田降低了单位面积穗数，提高了每穗粒数、结实率与千粒重，增加了产量，改善了稻米的外观品质与蒸煮品质。与FFP相比，SSNM显著提高水稻产量，降低了稻米蛋白质含量，改善了稻米的食味性。秸秆还田结合SSNM增大了籽粒最大灌浆速率与平均灌浆速率，缩短了活跃灌浆期，增加了粒重，并提高了氮收获指数、氮肥吸收利用率、氮肥农学利用率、氮肥生理利用率和氮肥偏生产力。【结论】秸秆还田结合SSNM可增加产量，改善稻米品质，提高氮肥利用效率。

英文摘要：

[Objective] The purpose of this study was to investigate the effects of wheat-residue application and nitrogen （N） management on grain yield and quality and nitrogen use efficiency in direct-seeding rice. [Method] A mid-season japonica rice cultivar of Yangjing 9538 was directly sown in the field. Three treatments of N-fertilizer application, farmers＇ N-fertilizer practice （FFP）, site-specific N management （SSNM） based on chlorophyll measurement （SPAD） readings, and no N application, and with or without wheat residue application were conducted. Grain yield and quality and N use efficiency were determined. [Result] In comparison with the wheat-residue removal treatment, the wheat-residue application （the residue was incorporated into soil） treatment reduced panicles, but increased spikelets per panicle, filled-grain percentages and 1 000-grain weight, therefore increased grain yield. This treatment also improved rice appearance and cooking qualities, under either SSNM or FFP. In comparison with FFP, SSNM increased grain yield, reduced the grain protein content, and improved rice cooking quality. In comparison with the wheat-residue removal plus FFP treatments, the wheat-residue application plus SSNM treatments enhanced the maximum grain filling rate and mean grain filling rate and shortened the active grain filling period, leading to an increase in grain weight. Such treatments increased N harvest index, N recovery efficiency, N agronomic use efficiency, N physiological efficiency, and N partial factor productivity. [ Conclusion] The results suggest that wheat-residue application combined with SSNM could not only increase grain yield and quality, but also improve N use efficiency in direct-seeding rice.