氮肥后移对不同氮效率水稻花后碳氮代谢的影响  

Effects of Postponing Nitrogen Topdressing on Post-anthesis Carbon and Nitrogen Metabolism in Rice Cultivars with Different Nitrogen Use Efficiencies

作　　者：孙永健[1] 孙园园[2] 严奉君[1] 杨志远[1] 徐徽[1] 李玥[1] 王海月[1] 马均[1] 

机构地区：[1]四川农业大学水稻研究所/农业部西南作物生理生态与耕作重点实验室,四川温江611130 [2]中国气象局成都高原气象研究所,四川成都610072

出　　处：《作物学报》2017年第3期407-419,共13页Acta Agronomica Sinica

基　　金：国家重点研发计划"粮食丰产增效科技创新"重点专项(2016YFD0300506);四川省教育厅重点项目(16ZA0044);农业部作物生理生态与耕作重点实验室开放课题(201303);国家科技支撑计划项目(2013BAD07B13);四川省育种攻关专项(2016NYZ0051)资助~~

摘　　要：以氮高效品种(德香4103)和氮低效品种(宜香3724)为材料,利用^(13)C和^(15)N双同位素示踪技术和生理生化分析方法,采用盆栽及大田试验,在施氮量180 kg hm^(–2)条件下,设置3种氮肥运筹方式,基肥∶蘖肥∶穗肥比例分别为5∶3∶2(N_1)、3∶3∶4(N_2)、3∶1∶6(N_3),以及不施氮(N_0)处理;研究其对不同氮效率水稻花后氮碳代谢的影响,并探讨氮肥后移下花后光合同化物及氮素累积、转运、分配的共性响应机制及其与产量的关系。结果表明,品种、氮肥运筹对花后氮素利用特征、光合同化物分配、生理特性及产量均存在显著影响。氮高效品种与氮肥后移量占总施氮量的40%、氮素穗肥运筹以倒四、倒二叶龄期等量追施相配套(N_2处理),能促进花后氮素累积,提高剑叶光合速率和1,5-二磷酸核酮糖羧化酶、谷氨酰胺合成酶等碳氮代谢关键酶活性,促进叶片、茎鞘、根系、穗各营养器官光合同化物及氮素累积与转运,进而提高产量及氮肥利用率,为本试验氮高效品种配套的氮肥运筹优化模式。花后不同氮肥运筹下,氮高效品种光合同化物、氮素的累积与转运,分别较氮低效品种高7.78~12.75 mg ^(13)C株^(–1)、15.14~18.78mg ^(15)N株^(–1);且叶片转运量分别较氮低效品种高1.70~2.93 mg ^(13)C株^(–1)、2.21~4.55 mg ^(15)N株^(–1),茎鞘转运量分别较氮低效品种高1.70~2.93 mg ^(13)C株^(–1)、0.05~1.14 mg ^(15)N株^(–1);而穗部氮高效与氮低效品种^(13)C同化物分别增加31.04~44.68 mg ^(13)C株^(–1)(占^(13)C总量的42.04%~46.38%)、24.94~34.26 mg ^(13)C株^(–1)(占^(13)C总量的36.45%~41.36%),^(15)N则分别增加35.56~46.58 mg ^(15)N株^(–1)(占^(15)N总量的61.82%~82.93%)、27.37~31.57 mg ^(15)N株^(–1)(占^(15)N总量的58.04%~68.31%)。氮高效品种花后具有强光合碳同化、氮素的协同吸收转运特征,以及碳氮代谢能力,来满足籽粒灌浆期对光合同化物及氮素的利用,�The optimal nitrogen（N） managements and the selection of genotypes with high N use efficiency（NUE） play a vital role in rice production aiminged at high yield and high NUE.Two rice cultivars,one with high-NUE（Dexiang 4103） and the other with low-NUE（Yixiang 3724） were used in pot and field experiments in 2013 and 2014.The total N fertilizer applied was 180 kg ha^（-1） of urea and three treatments were included：1） 50% basal dressing,30% topdressing at 7 d after transplanting（DAT）,and 20% topdressing at 4th leaves emerged from the top（N_1）,2） 30% basal dressing,30% topdressing at 7 DAT,40% topdressing was split into two equal applications at 4th and 2nd leaves emerged from the top,3） 20% basal dressing,20% topdressing at 7 DAT,60% topdressing was split into two equal applications at 4th and 2nd leaves emerged from the top,respectively.Double isotope tracing technique of ^（13）C and ^（15）N and physiological-biochemical analysis were used to study the accumulation,translocation,distribution of N and photosynthate,and the correlation between morphology and physiological-biochemical characteristics and their relationships with grain yield.There were significant effects of cultivars and N application modes on grain yield,as well as the absorption and translocation of N and photosynthate from full-heading to maturity stage.Compared with N_1 and N_3,N_2 treatment with high-NUE was the best model in this paper referred as the variety and N application coupling model,which could improve N accumulation in rice plant after anthesis,increase photosynthetic rate,activities of ribulose 1,5-bisphosphate carboxylase,and glutamine synthetase in flag leaves,promote accumulation and translocation of photosynthate and N,and then improve the yield and NUE.Double isotope labeling results showed that the accumulation amount of photosynthetic products and N in rice plant with high-NUE was 7.78–12.75 mg ^（13）C plant^（–1） and 15.14–18.78 mg ^（15）N plant^（–1） higher,the transl

关 键 词：同位素示踪 氮效率 水稻 氮肥 碳氮代谢 

分 类 号：S511[农业科学—作物学]