以玉米品种“郑单958”为材料，在大田条件下，研究了乙烯利（0和180 g hm–2）和氮肥水平（0、75、150和225 kg N hm–2）对夏玉米产量、氮素吸收和利用以及SPAD值的影响。结果表明，乙烯利处理显著降低了氮吸收量和吸收效率，但显著...以玉米品种“郑单958”为材料，在大田条件下，研究了乙烯利（0和180 g hm–2）和氮肥水平（0、75、150和225 kg N hm–2）对夏玉米产量、氮素吸收和利用以及SPAD值的影响。结果表明，乙烯利处理显著降低了氮吸收量和吸收效率，但显著提高氮利用效率，其中乙烯利处理氮农学效率比对照提高了32.7%~34.6%，而且乙烯利处理对玉米产量及其产量构成因素没有显著影响；随着施氮量增加，夏玉米产量、产量构成因素和氮吸收量显著增加，而氮吸收效率、氮利用效率、氮偏生产力和氮农学效率随之降低，其中225 kg N hm–2处理氮吸收量比0 kg N hm–2处理提高了68.4%~91.8%，但225 kg N hm–2和150 kg N hm–2处理之间的氮吸收量差异不显著。乙烯利和氮肥对氮吸收量、氮吸收效率和氮农学效率具有互作效应。喷施乙烯利和增施氮肥均能提高灌浆期穗位叶 SPAD 值，但两者之间没有互作效应。通过相关性分析表明，夏玉米产量与吐丝期氮吸收量、收获期氮吸收量、灌浆期穗位叶SPAD值显著正相关。展开更多
Improving nitrogen use efficiency （NUE） and decreasing N loss are critical to sustainable agriculture. The objective of this research was to investigate the effect of various fertilization regimes on yield, NUE, N a...Improving nitrogen use efficiency （NUE） and decreasing N loss are critical to sustainable agriculture. The objective of this research was to investigate the effect of various fertilization regimes on yield, NUE, N agronomic efficiency （NAE） and N loss in long-term （16- or 24-yr） experiments carried out at three rice-wheat rotation sites （Chongqing, Suining and Wuchang） in subtropical China. Three treatments were examined： sole chemical N, N＋phosphorus （NP）, and NP＋potassium （NPK） fertilizations. Grain yields at three sites were significantly increased by 9.3-81.6% （rice） and 54.5-93.8% （wheat） under NP compared with N alone, 1.7-9.8% （rice） and 0-17.6% （wheat） with NPK compared with NP. Compared to NP, NUE significantly increased for wheat at Chongqing （9.3%） and Wuchang （11.8%）, but not at Suining, China. No changes in NUE were observed in rice between NP and NPK at all three sites. The rice-wheat rotation＇s NAE was 3.3 kg kg1 higher under NPK than under NP at Chongqing, while NAE was similar for NP and NPK at Suining and Wuchang. We estimated that an uptake increase of 1.0 kg N hal would increase 40 kg rice and 30 kg wheat ha-1. Nitrogen loss/input ratios were -60, -40 or -30% under N, NP or NPK at three sites, indicating significant decrease of N loss by P or PK additions. We attribute part of the increase in NUE soil N accumulation which significantly increased by 25-55 kg ha-1 yr1 under NPK at three sites, whereas by 35 kg ha-1 yr-1 under NP at Chongqing only. This paper illustrates that apply P and K to wheat, and reduce K application to rice is an effective nutrient management strategy for both the NUE improvement and N losses reduction in China.展开更多
文摘以玉米品种“郑单958”为材料，在大田条件下，研究了乙烯利（0和180 g hm–2）和氮肥水平（0、75、150和225 kg N hm–2）对夏玉米产量、氮素吸收和利用以及SPAD值的影响。结果表明，乙烯利处理显著降低了氮吸收量和吸收效率，但显著提高氮利用效率，其中乙烯利处理氮农学效率比对照提高了32.7%~34.6%，而且乙烯利处理对玉米产量及其产量构成因素没有显著影响；随着施氮量增加，夏玉米产量、产量构成因素和氮吸收量显著增加，而氮吸收效率、氮利用效率、氮偏生产力和氮农学效率随之降低，其中225 kg N hm–2处理氮吸收量比0 kg N hm–2处理提高了68.4%~91.8%，但225 kg N hm–2和150 kg N hm–2处理之间的氮吸收量差异不显著。乙烯利和氮肥对氮吸收量、氮吸收效率和氮农学效率具有互作效应。喷施乙烯利和增施氮肥均能提高灌浆期穗位叶 SPAD 值，但两者之间没有互作效应。通过相关性分析表明，夏玉米产量与吐丝期氮吸收量、收获期氮吸收量、灌浆期穗位叶SPAD值显著正相关。
基金Financial supports are from the National Natural Science Foundation of China (41001175)the National Basic Research Program of China (2011CB100501)the Special Basic Research Fund for Public Institutes in China (202-2)
文摘Improving nitrogen use efficiency （NUE） and decreasing N loss are critical to sustainable agriculture. The objective of this research was to investigate the effect of various fertilization regimes on yield, NUE, N agronomic efficiency （NAE） and N loss in long-term （16- or 24-yr） experiments carried out at three rice-wheat rotation sites （Chongqing, Suining and Wuchang） in subtropical China. Three treatments were examined： sole chemical N, N＋phosphorus （NP）, and NP＋potassium （NPK） fertilizations. Grain yields at three sites were significantly increased by 9.3-81.6% （rice） and 54.5-93.8% （wheat） under NP compared with N alone, 1.7-9.8% （rice） and 0-17.6% （wheat） with NPK compared with NP. Compared to NP, NUE significantly increased for wheat at Chongqing （9.3%） and Wuchang （11.8%）, but not at Suining, China. No changes in NUE were observed in rice between NP and NPK at all three sites. The rice-wheat rotation＇s NAE was 3.3 kg kg1 higher under NPK than under NP at Chongqing, while NAE was similar for NP and NPK at Suining and Wuchang. We estimated that an uptake increase of 1.0 kg N hal would increase 40 kg rice and 30 kg wheat ha-1. Nitrogen loss/input ratios were -60, -40 or -30% under N, NP or NPK at three sites, indicating significant decrease of N loss by P or PK additions. We attribute part of the increase in NUE soil N accumulation which significantly increased by 25-55 kg ha-1 yr1 under NPK at three sites, whereas by 35 kg ha-1 yr-1 under NP at Chongqing only. This paper illustrates that apply P and K to wheat, and reduce K application to rice is an effective nutrient management strategy for both the NUE improvement and N losses reduction in China.
