ABSTRACT Electrical signals (ESs) can be induced by local action of stressors in plants; they influence numerous physiological processes (photosynthesis, transpiration, respiration, genes expression, synthesis of phytohormones, etc.) and, thereby, induce a systemic adaptation response. Development of optical methods of a remote sensing of this response can be important for agricultural and ecological monitoring. Preliminarily, we showed (Sukhova et al., Plant Sign Behav 2019; 14:e1610301) that burning-induced ESs induced changes in leaf reflectance at broad spectral bands (400–500, 500–600, 600–700, and 700–800 nm). The aims of the present work were (i) investigation of ESs influence on difference reflectance indices (RIs) calculated on the basis of these broad spectral bands and (ii) analysis of connection of the indices with water content in plants. Pea seedlings were investigated. ESs were induced by burning of the first mature leaf; ESs had high amplitudes in the second leaf and had low amplitudes in the fourth leaf. It was shown that ESs induced significant changes in RIs, which were calculated on basis of intensities of the reflected light at (i) 400–500 and 600–700 nm, (ii) 500–600 and 700–800 nm, and (iii) 600–700 and 700–800 nm. The effect was strong in the second leaf and weak in the fourth leaf; that is, the response was dependent on the magnitude of ESs. ESs-induced changes in RI were strongly connected with ESs-induced decrease of leaf water content which was estimated on basis of decrease of water index. Thus, broadband RIs can be used for revealing the ESs-induced systemic stress response in plants.

中文翻译：

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燃烧引起的电信号影响豌豆叶片的宽带反射指数和水分指数


摘要 植物中应激源的局部作用可以诱导电信号（ES）；它们影响许多生理过程（光合作用、蒸腾作用、呼吸作用、基因表达、植物激素的合成等），从而诱导全身适应反应。开发这种响应遥感的光学方法对于农业和生态监测非常重要。我们初步证明（Sukhova 等人，Plant Sign Behav 2019；14：e1610301）燃烧诱导的 ES 会导致宽光谱带（400-500、500-600、600-700 和 700-800）叶片反射率的变化纳米）。目前工作的目的是 (i) 调查 ES 对基于这些宽光谱带计算的差异反射指数 (RI) 的影响，以及 (ii) 分析指数与植物水分含量的关系。对豌豆幼苗进行了调查。 ES是通过燃烧第一片成熟的叶子来诱导的； ES 在第二片叶子中具有高振幅，在第四片叶子中具有低振幅。结果表明，ESs 引起 RI 的显着变化，这是根据 (i) 400-500 和 600-700 nm、(ii) 500-600 和 700-800 nm 以及 (iii) 的反射光强度计算的。 ) 600–700 和 700–800 nm。第二叶作用强，第四叶作用弱；也就是说，响应取决于 ES 的大小。 ESs 引起的 RI 变化与 ESs 引起的叶片含水量下降密切相关，叶片含水量是根据水分指数的下降来估计的。因此，宽带 RI 可用于揭示 ES 诱导的植物系统应激反应。