摘要
利用低氧法(2% O_2)研究了大豆叶片光呼吸速率(R_p)对光强和CO_2浓度的响应。结果表明:当光合有效辐射强度(PAR)小于600μmol·m^(-2)·s^(-1)时,大豆叶片的R_p随光强的升高而几乎直线增加;当PAR约为1200μmol·m^(-2)·s^(-1)时,R_p达到最大值(12.69·mol CO_2·m^(-2)·s^(-1)),随后R_p随PAR的升高呈下降趋势;构建的光呼吸速率与光强的方程式拟合结果表明,大豆叶片最大光呼吸速率为13.42·mol CO_2·m^(-2)·s^(-1),其对应的光强为1207.74·mol·m^(-2)·s^(-1),该拟合值与实际测量值极为吻合(P>0.05);当PAR一定(2000μmol·m^(-2)·s^(-1))时,随着CO_2浓度的增加(0~1200μmol·mol^(-1)),大豆叶片的R_p呈先升高后下降变化,在600μmol·mol^(-1)时达到最大值(9.97·mol CO_2·m^(-2)·s^(-1));构建的光呼吸速率与CO_2浓度的方程式拟合结果表明,大豆叶片最大光呼吸速率为10.21·mol CO_2·m^(-2)·s^(-1),其对应的外界CO_2浓度为625.74·mol·mol^(-1)。该拟合值也与实际测量值极为吻合(P"0.05)。本文所构建的方程式可较好地拟合光呼吸速率对不同光强和不同CO_2浓度的响应,这对定量研究光呼吸提供了强有力的手段。
The light and CO2responses of photorespiration rate (Rp) of soybean (Glycine max) leaves were studied under 2% and 21% O2. The results showed that Rp of soybean leaves increased almost linearly with increasing photosynthetically active radiation (PAR) when PAR was less than 600 μmol·m^-2·s^-1; Rp reached the maximum value of 12.69 μmol CO2·m^-2·s^-1 when PAR was about 1200 μmol·m^-2·s^-1, and then Rp decreased with increasing PAR. The function relationship between Rp and PAR was constructed. The fitted result showed that the maximum value of Rp (Ppmax) was 13.42 μmol CO2·m^-2·s^-1, and the light intensity corresponding to Ppmax was 1207.74 μmol·m^-2·s^-1. The fitted values were extremely in agreement with the measured values (P〈0.05). As air CO2 concentration (Ca) (0-1200 μmol·mol-1) increased, Rp of soybean leaves increased firstly and then decreased. It reached a maximum value of 9.97 μmol CO2·m^-2·s^-1 when Ca was about 600 μmol·mol-1. The function relationship between Rp and Ca was also constructed. The fitted result showed that the Ppmax was 10.21 SymbolmA@mol CO2·m^-2·s^-1, and the Ca corresponding to the Ppmax was 625.74 μmol·mol-1. The fitted values also accorded with the measured values (P〈0.05). Thus, it can be concluded that the constructed function relationships between Rp and PAR and between Rp andCa would provide a powerful means for the quantitative study of photorespiration of plant leaves.
出处
《生态学杂志》
CAS
CSCD
北大核心
2017年第9期2535-2541,共7页
Chinese Journal of Ecology
基金
国家自然科学基金项目(31560069)
江西省自然科学基金项目(20142BAB20402)
温州市重点科技创新团队项目(C20150008)资助
关键词
光呼吸
大豆
CO2浓度
光强
photorespiration
soybean
CO2 concentration
light intensity.