CO_2浓度升高下粳稻叶片光合作用对光强变化的响应  

Responses of photosynthesis in leaves of Japonica rice to light intensity at elevated CO_2 concentration

作　　者：刘晓萌 于凌飞 黄耀[1] 孙文娟[1] 刘超[3] 陈健[3] 胡正华[3] LIU Xiao-meng1,2, YU Ling-fei1 , HUANG Yao1 , SUN Wen-juan1 , LIU Chao3, CHEN Jian3, HU Zheng-hua3.(1State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China ;＂ Z University of Chinese Academy of Sciences, Beijing 100049, China; 3School of Applied Meteorology, Nanjing University of Information Science ＆ Technology, Nanjing 210044, China)

机构地区：[1]中国科学院植物研究所植被与环境变化国家重点实验室,北京100093 [2]中国科学院大学,北京100049 [3]南京信息工程大学应用气象学院,南京210044

出　　处：《生态学杂志》2018年第4期1051-1057,共7页Chinese Journal of Ecology

基　　金：国家自然科学基金重点项目(41530533)资助

摘　　要：为了研究不同CO_2浓度升高水平下水稻光合作用对光强变化的响应,以常规粳稻"南粳9108"为试验材料,利用开顶式气室(OTC),设置对照(CK,背景大气),CK+40μmol·mol-1(T1)和CK+200μmol·mol-1(T2)两个CO_2浓度升高水平,各设4个OTC作为重复。测定了拔节孕穗期、抽穗开花期和乳熟期不同光强水平下水稻叶片的净光合速率(Pn)和氮含量等,并采用非直角双曲线模型模拟确定光合作用参数。结果表明:T1处理的Pn仅在拔节孕穗期和乳熟期的低光强(PAR=400μmol·m-2·s-1)下略高于CK,在其他光强水平下与CK无显著差异,饱和光强下的净光合速率(Pn max)在3个生育期均与CK无显著差异;不同光强下T2处理的Pn和Pn max在拔节孕穗期和抽穗开花期比CK高34%~40%,在乳熟期与CK无显著差异;CO_2浓度升高200μmol·mol-1有降低叶片氮含量的趋势,但叶片尺度的光合氮素利用效率显著高于CK和T1处理,且随着光照的增强而进一步提升;CO_2浓度升高200μmol·mol-1有利于提升孕穗期和抽穗开花期的表观量子效率。To investigate the responses of photosynthesis in leaves of rice to light intensity atdifferent levels of elevated CO2 concentration, Japonica rice （Oryza sativa L.） ‘Nanjing 9018’ was grown at three levels of CO2 concentration,i.e., ambient （CK）, ambient ＋ 40 μmol·mol-1 （T1）, and ambient ＋ 200 μmol·mol-1 （T2） in opentop chambers （OTC）, with four OTCs as replicates for each treatment. We measured leaf net photosynthesis rate （Pn） and nitrogenconcentration at different light intensities at jointingbooting, headingflowering, and milking stages. Non-rectangular hyperbola function was used to fit Pn against light intensity. Pn in T1 was slightly higher than CK at jointingbooting stage and milking stage when light intensity was low （PAR=400 μmol·m-2·s-1）, and no significant difference was detected for all other light intensities at the three developmental stages.Pn at different light intensities and light saturated net photosynthesis （Pn max） in T2 was 34%-40% higher than those in CK at jointing-booting and heading-flowering stages, while there was no significant difference at milking stage. Leaf nitrogen concentrations tended to be lower in T2, while photosynthetic nitrogen use efficiency （PNUE） was significantly higher than that in CK and T1. The PNUE was enhanced with the increases of light intensity. In addition, elevated CO2 200 μmol·mol-1 was beneficial to improvement of the apparent quantum efficiency at jointing-booting and heading-flowering stages.

关 键 词：水稻 开顶式气室 CO2浓度升高 叶片光合作用 光强 叶片氮含量 

分 类 号：S511.22[农业科学—作物学]