Department of Biophysics, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia.
Plant Signal Behav. 2020 Apr 2;15(4):1737786. doi: 10.1080/15592324.2020.1737786. Epub 2020 Mar 9.
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.
电信号（ES）可以被植物中的应激源的局部作用所诱导；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、植物激素合成等），从而诱导系统适应反应。发展这种反应的光学遥感方法对于农业和生态监测可能很重要。初步研究表明（Sukhova 等人，植物信号行为 2019 年；14：e1610301），燃烧诱导的 ES 会引起叶片在宽光谱带（400-500nm、500-600nm、600-700nm 和 700-800nm）的反射率发生变化。本工作的目的是（i）研究 ES 对基于这些宽光谱带计算的差异反射率指数（RI）的影响，以及（ii）分析指数与植物水分的关系。研究了豌豆幼苗。通过燃烧第一片成熟叶片来诱导 ES；ES 在第二叶片中具有高振幅，而在第四叶片中具有低振幅。结果表明，ES 诱导了 RI 的显著变化，这些 RI 是基于反射光的强度计算的，包括（i）400-500nm 和 600-700nm，（ii）500-600nm 和 700-800nm，以及（iii）600-700nm 和 700-800nm。在第二叶片中的效果较强，而在第四叶片中的效果较弱；也就是说，这种反应与 ES 的幅度有关。ES 诱导的 RI 变化与 ES 诱导的叶片水分含量降低密切相关，后者是基于水分指数的降低来估算的。因此，宽带 RI 可用于揭示植物中 ES 诱导的系统应激反应。
