Triacontanol is a long-chain alcohol that is considered to be a plant growth promoter. Exogenous application of triacontanol increases dry and fresh weight, plant height, branching, stem and root length, yield, and other biochemical parameters; it also reduces the effect of different stressors. In this work, the effects of triacontanol on stomatal regulation and photochemical parameters in tomato plants exposed to three irradiance levels (100, 200, and 600 μmol m−2 s−1) were examined. Low and high irradiance levels caused a stress response in plants; photosystem II efficiency (ΦPSII) and photosynthetic-irradiance parameters were diminished. Triacontanol only reversed the negative effects of high irradiance, increasing photochemical response and photosynthetic-irradiance parameters. Moreover, a large population of low chloroplast number, chlorophyll content, and stomatal conductance were stimulated by triacontanol application. In relation to stomatal function, triacontanol had no effect on stomatal density; however, it affected stomatal size and morphology at the three irradiance levels evaluated. Bioassays in epidermal peels showed a direct effect on the stomatal aperture and an increase in aperture size in both light and dark conditions in triacontanol treatments. This is the first report of the role of triacontanol in the regulation of stomata and photochemical responses in relation to irradiance stress.

中文翻译：

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三十烷醇和光对茄属植物气孔和光化学反应的影响。

三十烷醇是一种长链醇，被认为是植物生长促进剂。外源施用三十烷醇可增加干重和鲜重、株高、分枝、茎和根长度、产量和其他生化参数；它还减少了不同压力源的影响。在这项工作中，检查了三十烷醇对暴露于三种辐照度水平（100、200 和 600 μmol m-2 s-1）的番茄植株气孔调节和光化学参数的影响。低辐照度和高辐照度水平引起植物的应激反应；光系统 II 效率 (ΦPSII) 和光合辐照度参数降低。三十烷醇只能逆转高辐照度的负面影响，增加光化学反应和光合辐照度参数。此外，大量的低叶绿体数量，三十烷醇的应用刺激了叶绿素含量和气孔导度。在气孔功能方面，三十烷醇对气孔密度没有影响；然而，它影响了评估的三个辐照度水平的气孔大小和形态。在三十烷醇处理中，表皮果皮中的生物测定显示对气孔孔径​​的直接影响和在明暗条件下孔径大小的增加。这是关于三十烷醇在调节与辐照胁迫相关的气孔和光化学反应中的作用的第一份报告。在三十烷醇处理中，表皮果皮中的生物测定显示对气孔孔径​​的直接影响和在明暗条件下孔径大小的增加。这是关于三十烷醇在调节与辐照胁迫相关的气孔和光化学反应中的作用的第一份报告。在三十烷醇处理中，表皮果皮中的生物测定显示对气孔孔径​​的直接影响和在明暗条件下孔径大小的增加。这是关于三十烷醇在调节与辐照胁迫相关的气孔和光化学反应中的作用的第一份报告。