The effect of leaf nitrogen and temperature on the CO2 response of photosynthesis in the C3 dicot Chenopodium album L.
The effect of leaf nitrogen and temperature on the CO2 response of photosynthesis in the C3 dicot Chenopodium album L.
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DOI：
10.1071/pp9900135
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发表时间：
1990
期刊：
影响因子：
--
通讯作者：
R. Sage;T. Sharkey;R. W. Pearcy
中科院分区：
文献类型：
--
作者：
R. Sage;T. Sharkey;R. W. Pearcy
研究了C3一年生藜（Chenopodium album L.）光合CO2响应的初始斜率和光合CO2饱和速率均与叶片有机氮含量呈线性关系。随着叶片氮素含量的增加或叶片温度的降低，光合作用的CO2饱和点降低。将叶温从15 ° C提高到34 ° C，可以刺激光合作用的CO2饱和速率，但对光合作用CO2响应的初始斜率影响不大。根据Sharkey（1985 Bot.修订版51：53 - 105），这些结果表明，随着叶氮的增加，RuP2羧化酶和RuP2再生的能力比淀粉和蔗糖合成再生正磷酸盐的能力增加的程度更大。因此，在高氮叶片，光合作用似乎是有限的能力，在较低的CO2分压比低氮叶片再生磷酸盐。在高氮叶片中，温度升高似乎在更大程度上提高磷酸再生能力比RuP2羧化酶的能力。因此，在寒冷条件下（<20 ° C），正常大气中的CO2同化似乎受到磷酸盐再生能力的限制，而在温暖条件下（34 ° C），RuP2羧化酶能力似乎限制了CO2同化。
The CO2 response of photosynthesis was studied in the C3 annual, Chenopodium album L. Both the initial slope of the photosynthetic CO2 response and the CO2 saturated rate of photosynthesis were linearly dependent on organic leaf nitrogen content. As leaf nitrogen increased or leaf temperature declined, the CO2 saturation point of photosynthesis declined. Increasing leaf temperature from 15 to 34°C stimulated the CO2-saturated rate of photosynthesis but had little effect on the initial slope of the photosynthetic CO2 response. According to the photosynthesis model of Sharkey (1985 Bot. Rev. 51: 53-105), these results indicate that as leaf nitrogen increased, the capacity for RuP2 carboxylase and RuP2 regeneration increased to a greater extent than the capacity of starch and sucrose synthesis to regenerate orthophosphate. As a result, in high nitrogen leaves, photosynthesis appeared to be limited by the capacity to regenerate phosphate at lower CO2 partial pressures than in low nitrogen leaves. In high nitrogen leaves, increasing temperature appeared to enhance the phosphate regeneration capacity to a greater extent than the capacity of RuP2 carboxylase. Consequently, while under cool conditions (<20°C), CO2 assimilation in normal atmospheric air appeared to be limited by the phosphate regeneration capacity, under warm conditions (34°C), RuP2 carboxylase capacity appeared to limit CO2 assimilation.