Photosystem I in low light-grown leaves of Alocasia odora, a shade-tolerant plant, is resistant to fluctuating light-induced photoinhibition.
Photosystem I in low light-grown leaves of Alocasia odora, a shade-tolerant plant, is resistant to fluctuating light-induced photoinhibition.
复制标题
海芋（一种耐荫植物）在弱光下生长的叶子中的光系统 I 能够抵抗波动光引起的光抑制。
DOI：
10.1007/s11120-021-00832-4
复制
发表时间：
2021
影响因子：
3.7
通讯作者：
Kono M.
中科院分区：
文献类型：
--
作者：
Terashima I;Matsuo M;Suzuki Y;Yamori Y;Kono M.
当完整的绿叶暴露在强光和弱光交替的波动光下时，光系统I （PSI）容易受到破坏。这种PSI抑制主要是通过添加远红光（FR）光来减轻的。在此，我们在不同的光照水平下培育了耐荫植物walocasia odora，并研究了它们的光合特性与波动光诱导的PSI抑制的关系。我们发现，即使在没有FR的情况下，ll -生长叶片中的PSI也能抵抗波动光。77 K荧光分析显示，以叶面积计算，LL叶片叶绿素含量较高，Chla/bratios较低，细胞色素/P700比较低，PSII/PSI激发比较低。P700在波动光的HL相中氧化程度更高。PSI光抑制对上述性状的回归分析表明，较低的电子流向P700的速率和较多的激发能转移到PSI对低生长叶片的PSI有保护作用。这两种方法都有助于P700的氧化形成P700+的高效淬灭剂。这些特征可能在ll生长的耐阴物种中很常见，这些物种在自然栖息地经常暴露在强烈的太阳斑下。
When intact green leaves are exposed to the fluctuating light, in which high light (HL) and low light (LL) alternate, photosystem I (PSI) is readily damaged. This PSI inhibition is mostly alleviated by the addition of far-red (FR) light. Here, we grewAlocasia odora, a shade-tolerant species, at several light levels and examined their photosynthetic traits in relation to the fluctuating light-induced PSI inhibition. We found that, even in the absence of FR, PSI in LL-grown leaves was resistant to the fluctuating light. LL leaves showed higher chlorophyll (Chl) contents on leaf area basis, lower Chla/bratios, lower cytochromef/P700 ratios, and lower PSII/PSI excitation ratios assessed by the 77 K fluorescence. Also, P700 in the HL phase of the fluctuating light was more oxidized. The results of the regression analyses of the PSI photoinhibition to these traits indicate that the lower electron flow rate to P700 and more excitation energy transfer to PSI protect PSI in LL-grown leaves. Both of these contribute oxidization of P700 to the efficient quencher form P700+. These features may be common in LL-grown shade-tolerant species, which are often exposed to strong sunflecks in their natural habitats.