碳同位素表征干旱条件下大豆水氮利用效率  

Use Efficiency of Water and Nitrogen of Soybean with Water Stress by Stable Carbon Isotope Discrimination

作　　者：姜浩 陈鹏 Shehakk 张忠学 JIANG Hao;CHEN Peng;Shehakk;ZHANG Zhong-xuea(College of Water Conservancy and Civil Engineering,Northeast Agricultural University,Harbin 150030,China;Key Laboratory of Effective Utili-zation of Agricultural Water Resouwes,Ministry of Agriculture,Harbin 150030,China)

机构地区：[1]东北农业大学水利与土木工程学院,黑龙江哈尔滨150030 [2]农业部农业水资源高效利用重点实验室,黑龙江哈尔滨150030

出　　处：《大豆科学》2018年第6期906-914,共9页Soybean Science

基　　金：国家科技支撑计划(2014BAD11B01)

摘　　要：为研究不同生育期水分胁迫条件下大豆叶片水分及氮素高效利用机理,利用盆栽试验研究不同生育期水分胁迫对大豆叶片瞬时水分利用效率(WUE_i)、内在水分利用效率(WUE_n)、氮素利用效率(NUE)和碳同位素分辨率(Δ^(13)C)的影响,探讨Δ^(13)C表征大豆水氮利用效率的可行性。结果表明:水分胁迫在一定程度上影响大豆水分利用效率,并且在开花期轻度水分胁迫条件下,水分利用效率提升效果最为显著;水分胁迫处理下各生育时期的大豆叶片C/N均表现为:重度胁迫>中度胁迫>轻度胁迫;在各生育期内,大豆叶片Δ^(13)C与WUE_i、WUE_n和NUE均呈负相关,开花期水分胁迫条件下叶片Δ^(13)C与WUE_i、WUE_n及NUE的相关性较苗期相同程度水分胁迫处理更为显著,并且各处理叶片Δ^(13)C对WUE_n的指示性均优于WUE_i。水分胁迫处理能够显著提升水氮利用效率,并且Δ^(13)C与WUE_i、WUE_n及NUE之间具有显著的相关关系,该研究有利于揭示不同生育期水分管理模式大豆叶片碳氮代谢规律,为通过控水方式提高大豆水分利用效率提供理论依据。Carbon isotope discrimination （Δ^13C） could comprehensively reflect the ratio of intercellular CO2 concentration （ Ci ） to CO2 concentration （ Ca ） during a period. Ci/Ca reflects the relative amount of photosynthetic rate （ Pn ） and stomatal conductance （Gs） corresponding to CO2 demand and supply. When any of Pn and G, changes, Ci/Ca will obviously change and ultimately affect water use efficiency（WUE）. Therefore, it is possible to infer crop WUE by measuring crop Δ^13C. Δ^13C can also be used to deduce instantaneous water use efficiency （ WUEi ） and intrinsic water use efficiency （ WUEn ） at leaf lev- el. And it is considered as a reliable method for long-term estimation of crop water use efficiency. In addition, leaf nutrient use efficiency （NUE） is the basis of crop growth and high yield, and can be used as a main indicator to reflect crop nutrient absorption characteristics. The ratio of soluble sugar content and nitrogen content （ C/N ） is selected as a crop NUE index in this experiment to reflect the C acquisition and assimilation rate, N distribution and utilization ratio of plant. At present, the research on indicator relationship between crop leaf tissue Δ^13c and crop WUE and NUE mainly focuse on maize, tomato, and rice under water stress, while there are few studies on soybean with water stress at different growth stages. This study combines theoretical analysis with field experiments to analyze the relationship between soybean leaf Δ^13C and WUE and NUE at seed- ling and flowering stage of soybean with water stress, respectively, to reveal the regulation of carbon and nitrogen metabolism in soybean leaves during different growth periods, which can provide theoretical basis for the efficient use of water and nutrient of crop at leaf level. The experiment was conducted at the experimental station of Northeast Agricultural University in Harbin, Heilongjiang province in 2017. The leaf Δ^13C, photosynthetic rate （Pn）, transpiration rate （Tr）, stomatal

关 键 词：大豆 胁迫时期 叶片水分利用效率 叶片氮素利用效率 碳同位素分辨率(△^13C) 

分 类 号：S565.1[农业科学—作物学]