金光菊属 Flaveria brownii A.M. Powell 的光合作用：一种 C(4)-样 C(3)-C(4)中间型。

Photosynthesis in Flaveria brownii A.M. Powell : A C(4)-Like C(3)-C(4) Intermediate.

机构信息

Department of Environmental, Population and Organismic Biology, University of Colorado, Campus Box 334, Boulder, Colorado 80309.

出版信息

Plant Physiol. 1987 Dec;85(4):1063-7. doi: 10.1104/pp.85.4.1063.

DOI:10.1104/pp.85.4.1063

PMID:16665804

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC1054394/

Abstract

Leaves of Flaveria brownii exhibited slightly higher amounts of oxygen inhibition of photosynthesis than the C(4) species, Flaveria trinervia, but considerably less than the C(3) species, Flaveria cronquistii. The photosynthetic responses to intercellular CO(2), light and leaf temperature were much more C(4)-like than C(3)-like, although 21% oxygen inhibited the photosynthetic rate, depending on conditions, up to 17% of the photosynthesis rate observed in 2% O(2). The quantum yield for CO(2) uptake in F. brownii was slightly higher than that for the C(4) species F. trinervia in 2% O(2), but not significantly different in 21% O(2). The quantum yield was inhibited 10% in the presence of 21% O(2) in F. brownii, yet no significant inhibition was observed in F. trinervia. An inhibition of 27% was observed for the quantum yield of F. cronquistii in the presence of 21% O(2). The photosynthetic response to very low intercellular CO(2) partial pressures exhibited a unique pattern in F. brownii, with a break in the linear slope observed at intercellular CO(2) partial pressure values between 15 and 20 mubar when analyzed in 21% O(2). No significant break was observed when analyzed in 2% O(2). When taken collectively, the gas-exchange results reported here are consistent with previous biochemical studies that report incomplete intercellular compartmentation of the C(3) and C(4) enzymes in this species, and suggest that F. brownii is an advanced, C(4)-like C(3)-C(4) intermediate.

摘要

皱叶酸模的叶片表现出比 C4 物种三叶滨藜稍高的光合作用氧抑制程度，但比 C3 物种 Cronquist 皱叶酸模低得多。对胞间 CO2、光和叶温的光合响应更类似于 C4，而不是 C3，尽管 21%的氧在不同条件下可抑制光合作用速率，高达 2%O2 下观察到的光合作用速率的 17%。在 2%O2 中，Flaveria brownii 的 CO2 摄取量子产率略高于 C4 物种三叶滨藜，但在 21%O2 中没有显著差异。在 21%O2 存在的情况下，Flaveria brownii 的量子产率受到 10%的抑制，但在三叶滨藜中未观察到明显的抑制。在 21%O2 存在的情况下，Flaveria cronquistii 的量子产率抑制了 27%。在 21%O2 中分析时，Flaveria brownii 对非常低的胞间 CO2 分压的光合响应表现出独特的模式，在线性斜率上出现中断，在胞间 CO2 分压值在 15 到 20 mubar 之间。在 2%O2 中分析时没有观察到明显的中断。总的来说，这里报道的气体交换结果与先前的生化研究一致，这些研究报告了该物种中 C3 和 C4 酶不完全的细胞间区室化，并表明 Flaveria brownii 是一种先进的、类似于 C4 的 C3-C4 中间型。