中籼水稻品种改良对氮肥利用率的影响及其生理机制.pdf

中籼水稻品种改良对氮肥利用率的影响及其生理机制 刘立军 杨建昌．徐伟 王志琴 朱庆森 (扬州大学农学院农学系，江苏扬州225009) 摘要我国中籼水稻品种改良经历了由高秆品种、改良高秆品种、矮秆品种、半矮秆常规品种和杂交种到现代 超级稻品种等5个典型阶段。本试验以上述5个阶段16个代表性的中籼水稻品种为材料，研究了品种演进对水稻 产量和氮肥利用率的影响。结果表明：随着品种改良，水稻产量逐步提高。品种改良提高了抽穗前水稻的干物重 和吸氮量以及抽穗后氮素向籽粒的运转。抽穗期吸氮量以及抽穗后氮素运转率与水稻产量均呈显著正相关。穗分 GOGAT的活性明显受到氮肥的调节。穗分化期和灌浆初期氮代谢酶类活性的提高能增加抽穗前氮素吸收和干物质 积累，促进氮由营养器官向籽粒的运转，提高水稻产量。品种改良较大幅度地提高了现代品种的氮肥生理利用率、 农学利用率和氮肥偏生产力，但品种改良没有能够提高水稻的氮肥吸收利用率。 关键词水稻；品种改良；产量；氮肥利用率；生理机制 EffectofGenetic ofMid—seasonIndicaRiceon Use Improvement Nitrogen andIts Mechanism EfficiencyPhysiological LIU NG Li。Jun，YANG W．ei，Ⅵ，A Jian—Chang，XU Zlli．Qin，ZHUQing．Sen (DepartmentofAgronomy,AgriculturalCollege．Yangzhou AbstractIn mid-seasonindicarice five China，genetic experiencedtypical improvement(GI)of stages，i．e． tall tall and cultivarsand cultivars，dwarfcultivars，semi-dwarf,conventional earlycultivars，improved hybrid ricecukivars．With16 mid·seasonindicacultivarsthefive as materials， super representative during stages effectofGIon and use wasstudied．TheresultsshowedthatGIincreased grain yieldnitrogenefficiency grain increasedbiomassandN before andenhancedNremobilizationafter stage yieldgradually．GI uptake heading at andNtranslocationwere correlatedwiththe stage efficiencysignificantly headingstage．Nuptakeheading