Inside out: efflux of carbon dioxide from leaves represents more than leaf metabolism.
Inside out: efflux of carbon dioxide from leaves represents more than leaf metabolism.
复制标题
DOI：
10.1093/jxb/erx155
复制
发表时间：
2017-05-17
影响因子：
6.9
通讯作者：
Hanson DT
中科院分区：
文献类型：
--
作者：
Stutz SS;Anderson J;Zulick R;Hanson DT
通过向叶片供应13 C，显示了呼吸CO2的运输对测量的叶片呼吸的影响。根、茎和分支呼吸作用产生的木质部中的高浓度无机碳通过蒸腾流传播，并最终以CO2的形式通过远处的组织离开植物。与以往的研究，侧重于从根和木质组织的CO2外排，我们专注于从叶片的外排和叶片呼吸测量的潜在影响。我们标记运输的无机碳，跨越报告的木质部浓度，与13 C，然后操纵蒸腾速率在黑暗中，以改变无机碳供应率削减叶片从甘蓝型油菜和美洲黑杨。我们使用可调谐二极管激光吸收光谱法直接测量总13 CO2流出率，来自外部的叶提供的无机碳，相对于总12 CO2流出产生的叶细胞。这些实验表明，~（13）CO_2排放量取决于叶片无机碳供应速率和蒸腾速率。我们的数据表明，木质部运输的CO2的总叶流出量可能是小的，在黑暗中，蒸腾速率低。然而，木质部运输的CO2的总叶流出量可以接近一半的光叶呼吸速率时，蒸腾速率和分支无机碳浓度高，无论在我们的实验中的叶柄形态的严重不同。
Through supplying 13C to leaves, the effect of the transportation of respired CO2 on measured leaf respiration is shown. High concentrations of inorganic carbon in the xylem, produced from root, stem, and branch respiration, travel via the transpiration stream and eventually exit the plant through distant tissues as CO2. Unlike previous studies that focused on the efflux of CO2 from roots and woody tissues, we focus on efflux from leaves and the potential effect on leaf respiration measurements. We labeled transported inorganic carbon, spanning reported xylem concentrations, with 13C and then manipulated transpiration rates in the dark in order to vary the rates of inorganic carbon supply to cut leaves from Brassica napus and Populus deltoides. We used tunable diode laser absorbance spectroscopy to directly measure the rate of gross 13CO2 efflux, derived from inorganic carbon supplied from outside of the leaf, relative to gross 12CO2 efflux generated from leaf cells. These experiemnts showed that 13CO2 efflux was dependent upon the rate of inorganic carbon supply to the leaf and the rate of transpiration. Our data show that the gross leaf efflux of xylem-transported CO2 is likely small in the dark when rates of transpiration are low. However, gross leaf efflux of xylem-transported CO2 could approach half the rate of leaf respiration in the light when transpiration rates and branch inorganic carbon concentrations are high, irrespective of the grossly different petiole morphologies in our experiment.
登录
查看更多内容
影响因子：
64.8
作者：
Crowther, T. W.;Glick, H. B.;Bradford, M. A.
通讯作者：
Bradford, M. A.
影响因子：
7.3
作者：
Barbour, Margaret M.;McDowell, Nate G.;Hanson, David T.
通讯作者：
Hanson, David T.
影响因子：
9.4
作者：
Barron-Gafford, Greg A.;Grieve, Katherine A.;Murthy, Ramesh
通讯作者：
Murthy, Ramesh
影响因子：
2.3
作者：
Bloemen, Jasper;Teskey, R. O.;Steppe, K.
通讯作者：
Steppe, K.
影响因子：
9.4
作者：
Bloemen, Jasper;McGuire, Mary Anne;Steppe, Kathy
通讯作者：
Steppe, Kathy