实时实地氮肥管理对水稻产量和稻米品质的影响

【目的】探讨实时实地氮肥管理对水稻产量和品质的影响。【方法】试验于2004和2005年在大田条件下，以两优培九、汕优63为材料研究了不同叶绿素仪（SPAD）预设阈值指导下的实时实地氮肥管理方式的产量与产量形成以及相应的稻米品质特性。【结果】在实时氮肥管理（RTNM）模式下，两优培九和汕优63各施氮处理比不施氮处理增产幅度分别达21.12%～57.65%和15.00%～31.18%。在实地氮肥管理（SSNM）模式下，两优培九和汕优63 SSNM处理比不施氮小区增产幅度分别达45.44%～50.71%和28.53%～32.40%。两优培九SPAD阈值分别由34～45的RTNM模式下，当SPAD阈值介于38～41之间时（氮肥用量120～165 kgN•ha-1）可以改善稻米的外观品质和加工品质；汕优63则以SPAD阈值36～39（氮肥用量：120～165 kgN•ha-1）范围内有利于改善米质。SSNM模式下以SPAD施肥阈值为37-39（氮肥用量130 kgN•ha-1）进行氮肥运筹能显著改善两优培九的加工品质、外观品质和营养品质；SSNM模式下汕优63以SPAD阈值为35～37时稻米品质相对较好，同时产量也比较高。【结论】实时实地氮肥管理能较好地协调水稻产量和品质的关系，关键措施是依据品种特性确定适宜的预设SPAD阈值。在本试验条件下，实时实地氮肥管理模式两优培九以SPAD 38～39、汕优63以SPAD 35～37左右时能获得较高的产量和部分地改善米质，可以作为生产上应用实时实地氮肥管理时的推荐阈值。

Effect of Real-Time and Site-Specific Nitrigen Management on Rice Yield and Quality

To evaluate the effect of real-time and site-specific N management on rice yield and its quality, the experiments under field conditions were conducted with indica hybrid rice Liangyoupei9(LYP9) and Shanyou63(SY63) in 2004 and 2005. The results showed that grain yield of LYP9 and SY63 under N-application treatment increased by 21.12%-57.65%, 15.00%-31.18% compared to no N-application treatment respectively based on the Real-time N Management (RTNM); grain yield of LYP9 and SY63 under N-application treatment increased by 45.44%-50.71%, 28.53%-32.40% compared to no N-application treatment respectively based on the Site-specific N Management(SSNM). The recommended SPAD threshold were 38-41 for LYP9, and 36-39 for SY63, which might obtain higher grain yield and better grain quality when RTNM were adapted for nitrogen management. The optimal SPAD threshold for LYP9 and SY63 were 38-39 and 36 respectively, when nitrogen management based on SSNM. It clearly demonstrated that the milling quality, apparent features, protein content of LYP9 was noticeably improved under a proper SPAD threshold based on the SSNM both in 2004 and 2005; For SY63, its quality could not be improved in SSNM while the SPAD threshold recommendation based on the grain yield performance. The results indicate the possibility of harmonizing the conflict of rice quality and grain yield by using SSNM based on the recommendation SPAD threshold value of 38-39 for LYP9 and 36 or so for SY63.