Journal of Integrative Agriculture ›› 2014, Vol. 13 ›› Issue (1): 73-81.DOI: 10.1016/S2095-3119(13)60349-4

• 论文 • 上一篇    下一篇

Nitrogen Deficiency Limited the Improvement of Photosynthesis in Maize by Elevated CO2 Under Drought

 ZONG Yu-zheng, SHANGGUAN Zhou-ping   

  1. 1.National Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling 712100, P.R.China
    2.University of Chinese Academy of Sciences, Beijing 100049, P.R.China
  • 收稿日期:2012-11-11 出版日期:2014-01-01 发布日期:2014-01-04
  • 通讯作者: SHANGGUAN Zhou-ping, Tel: +86-29-87019107, Fax: +86-29-87012210, E-mail: shangguan@ms.iswc.ac.cn
  • 作者简介:SHANGGUAN Zhou-ping, Tel: +86-29-87019107, Fax: +86-29-87012210, E-mail: shangguan@ms.iswc.ac.cn
  • 基金资助:

    The study was financially supported by the National Natural Science Foundation of China (31370425, 61273329) and the Specialized Research Fund for the Doctoral Program of Higher Education, China (20130204110024).

Nitrogen Deficiency Limited the Improvement of Photosynthesis in Maize by Elevated CO2 Under Drought

 ZONG Yu-zheng, SHANGGUAN Zhou-ping   

  1. 1.National Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences, Yangling 712100, P.R.China
    2.University of Chinese Academy of Sciences, Beijing 100049, P.R.China
  • Received:2012-11-11 Online:2014-01-01 Published:2014-01-04
  • Contact: SHANGGUAN Zhou-ping, Tel: +86-29-87019107, Fax: +86-29-87012210, E-mail: shangguan@ms.iswc.ac.cn
  • About author:SHANGGUAN Zhou-ping, Tel: +86-29-87019107, Fax: +86-29-87012210, E-mail: shangguan@ms.iswc.ac.cn
  • Supported by:

    The study was financially supported by the National Natural Science Foundation of China (31370425, 61273329) and the Specialized Research Fund for the Doctoral Program of Higher Education, China (20130204110024).

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摘要： Global environmental change affects plant physiological and ecosystem processes. The interaction of elevated CO2, drought and nitrogen (N) deficiency result in complex responses of C4 species photosynthetic process that challenge our current understanding. An experiment of maize (Zea mays L.) involving CO2 concentrations (380 or 750 μmol mol-1, climate chamber), osmotic stresses (10% PEG-6000, -0.32 MPa) and nitrogen constraints (N deficiency treated since the 144th drought hour) was carried out to investigate its photosynthesis capacity and leaf nitrogen use efficiency. Elevated CO2 could alleviate drought-induced photosynthetic limitation through increasing capacity of PEPC carboxylation (Vpmax) and decreasing stomatal limitations (SL). The N deficiency exacerbated drought-induced photosynthesis limitations in ambient CO2. Elevated CO2 partially alleviated the limitation induced by drought and N deficiency through improving the capacity of Rubisco carboxylation (Vmax) and decreasing SL. Plants with N deficiency transported more N to their leaves at elevated CO2, leading to a high photosynthetic nitrogen-use efficiency but low whole-plant nitrogen-use efficiency. The stress mitigation by elevated CO2 under N deficiency conditions was not enough to improving plant N use efficiency and biomass accumulation. The study demonstrated that elevated CO2 could alleviate drought-induced photosynthesis limitation, but the alleviation varied with N supplies.

关键词: drought , elevated CO2 , N deficiency , photosynthesis

Abstract: Global environmental change affects plant physiological and ecosystem processes. The interaction of elevated CO2, drought and nitrogen (N) deficiency result in complex responses of C4 species photosynthetic process that challenge our current understanding. An experiment of maize (Zea mays L.) involving CO2 concentrations (380 or 750 μmol mol-1, climate chamber), osmotic stresses (10% PEG-6000, -0.32 MPa) and nitrogen constraints (N deficiency treated since the 144th drought hour) was carried out to investigate its photosynthesis capacity and leaf nitrogen use efficiency. Elevated CO2 could alleviate drought-induced photosynthetic limitation through increasing capacity of PEPC carboxylation (Vpmax) and decreasing stomatal limitations (SL). The N deficiency exacerbated drought-induced photosynthesis limitations in ambient CO2. Elevated CO2 partially alleviated the limitation induced by drought and N deficiency through improving the capacity of Rubisco carboxylation (Vmax) and decreasing SL. Plants with N deficiency transported more N to their leaves at elevated CO2, leading to a high photosynthetic nitrogen-use efficiency but low whole-plant nitrogen-use efficiency. The stress mitigation by elevated CO2 under N deficiency conditions was not enough to improving plant N use efficiency and biomass accumulation. The study demonstrated that elevated CO2 could alleviate drought-induced photosynthesis limitation, but the alleviation varied with N supplies.

Key words: drought , elevated CO2 , N deficiency , photosynthesis