Temperature responses of photosynthesis and respiration in Populusbalsamifera L.: acclimation versus adaptation
Temperature responses of photosynthesis and respiration in Populusbalsamifera L.: acclimation versus adaptation
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DOI：
10.1007/s11120-010-9527-y
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发表时间：
2010-01
影响因子：
3.7
通讯作者：
S. Silim;Natalie Ryan;D. S. Kubien
中科院分区：
文献类型：
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作者：
S. Silim;Natalie Ryan;D. S. Kubien
为探讨驯化与适应对CO2同化温度响应的作用，测定了生长于温凉生境和温凉生境的香杨（Populus balsamiferaL.）的暗呼吸（Rn）和净光合作用的CO2响应（A），结果表明，生长于19 ℃和27 ℃的香杨（Populus balsamiferaL.）不受原生热生境的影响。相比之下，Rubisco的最大容量（Vcmax）和A对生长温度相对不敏感，但这两个参数在凉爽生境的植物中略高。无论生长温度如何，A都受到Rubisco容量的限制，并且几乎没有证据表明电子传递受到限制。气孔导度（gs）在温暖生长的植物中较高，但随着测量温度从17 ° C增加到37°C而下降，而与生长温度无关。叶肉电导率（gm）在低于25°C时对温度相对不敏感，但在冷生植物中gm在37°C时下降。植物适应凉爽的温度增加了Rn/A，但这种反应并没有不同的温暖和凉爽的适应人群。初级碳代谢明显适应生长温度。balsamifera，但在A的生态型差异表明，全球变暖的情况可能会影响人口在北方和南部边缘的北方森林以不同的方式。
To examine the role of acclimation versus adaptation on the temperature responses of CO2assimilation, we measured dark respiration (Rn) and the CO2response of net photosynthesis (A) inPopulus balsamiferacollected from warm and cool habitats and grown at warm and cool temperatures.Rnand the rate of photosynthetic electron transport (J) are significantly higher in plants grown at 19 versus 27°C;Rnis not affected by the native thermal habitat. By contrast, both the maximum capacity of rubisco (Vcmax) andAare relatively insensitive to growth temperature, but both parameters are slightly higher in plants from cool habitats.Ais limited by rubisco capacity from 17–37°C regardless of growth temperature, and there is little evidence for an electron-transport limitation. Stomatal conductance (gs) is higher in warm-grown plants, but declines with increasing measurement temperature from 17 to 37°C, regardless of growth temperature. The mesophyll conductance (gm) is relatively temperature insensitive below 25°C, butgmdeclines at 37°C in cool-grown plants. Plants acclimated to cool temperatures have increasedRn/A, but this response does not differ between warm- and cool-adapted populations. Primary carbon metabolism clearly acclimates to growth temperature inP. balsamifera, but the ecotypic differences inAsuggest that global warming scenarios might affect populations at the northern and southern edges of the boreal forest in different ways.