大气CO_2浓度升高对谷子生长发育与光合生理的影响

研究大气CO2浓度升高对谷子的影响,有助于人们了解未来气候变化后,谷子生产的变化,以提前采取必要的应对措施趋利避害。本研究利用FACE(FreeAirCO2Enrichment)系统首次在大田条件进行了谷子生长发育受CO2浓度升高影响的试验。结果表明,大气CO2浓度升高后,谷子的株高、茎粗、叶面积增加,叶片叶绿素含量下降。在相同CO2浓度下,抽穗期FACE圈内谷子叶片气孔导度(Gs)、蒸腾速率(Tr)和胞间CO2浓度与环境CO2浓度的比值(Ci/Ca)会下降,叶片光合能力有所下降,出现光适应,但水分利用效率(WUE)会提高。

EFFECTS OF AIR CO2 ENRICHMENT ON GROWTH AND PHOTOSYNTHETIC PHYSIOLOGY OF MILLET

Elevation of ［CO2］ will invariably influence the growth and photosynthesis of millet and somewhat counteract the adverse impacts of rising temperature. Research on millet response to elevated ［CO2］ will generate information on changes in millet yield under future climate change and corresponding measures. The present study is the first reported FACE(Free air CO2 enrichment) experiment of millet in the world. Elevated ［CO2］ increased the height, stem diameter and leaf area of millet,but reduced the chlorophyll content of leaf.Photosynthesis(Pn), stomatal conductance (Gs), transpiration rate (Tr)and the ratio of intercellular CO2 concentration and extracellular CO2 concentration (Ci/Ca) were reduced in FACE at tassel period, but water use efficiency (WUE) was enhanced.