Sukhov Vladimir, Surova Lyubov, Sherstneva Oksana, Vodeneev Vladimir
Department of Biophysics, N.I. Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, 603950, Russia.
Physiol Plant. 2014 Dec;152(4):773-83. doi: 10.1111/ppl.12208. Epub 2014 May 23.
Electrical signals [action potentials (APs) and variation potentials (VPs)] induced by local stimuli are a mechanism that underlies rapid plant response to environmental factors. Such signals induce a number of functional responses, including changes in photosynthesis. Ultimately, these responses are considered to increase plant resistance to stress factors, but this question has been poorly investigated. We studied the influence of VP on photosynthesis and resistance of the photosynthetic machinery to heating in leaves of pea (Pisum sativum). Localized burning induced a VP that decreased photosynthesis parameters [CO(2) assimilation rate and quantum yields of photosystem I (PSI) and photosystem II (PSII)]. The photosynthetic response was initiated by a decrease in photosynthesis dark-stage activity, which in turn increased resistance of PSI to heating. Three results supported this hypothesized mechanism: (1) the magnitude of VP-induced decrease in CO(2) assimilation and enhanced PSI resistance to heating were highly correlated; (2) the VP influence on PSI resistance to heating was suppressed under a low external CO(2) concentration and (3) decreasing external CO(2) concentration imitated the VP-induced photosynthetic response and increased PSI resistance to heating.
由局部刺激诱导产生的电信号[动作电位（APs）和变异电位（VPs）]是植物对环境因素快速响应的一种潜在机制。这类信号会引发一系列功能反应，包括光合作用的变化。最终，这些反应被认为能增强植物对胁迫因子的抗性，但这一问题尚未得到充分研究。我们研究了变异电位对豌豆（Pisum sativum）叶片光合作用及光合机构耐热性的影响。局部灼烧诱导产生了一种变异电位，它降低了光合作用参数[二氧化碳同化率以及光系统I（PSI）和光系统II（PSII）的量子产率]。光合反应是由光合作用暗反应阶段活性的降低引发的，这反过来又增强了PSI的耐热性。三个结果支持了这一假设机制：（1）变异电位诱导的二氧化碳同化降低幅度与增强的PSI耐热性高度相关；（2）在低外部二氧化碳浓度下，变异电位对PSI耐热性的影响受到抑制；（3）降低外部二氧化碳浓度模拟了变异电位诱导的光合反应，并增强了PSI的耐热性。
