Lee Sang Joon, Kim Jeongju, Kim Hyejeong, Ryu Jeongeun
Department of Mechanical Engineering, Pohang University of Science and Technology Pohang 37673 South Korea
RSC Adv. 2018 Apr 20;8(27):15141-15148. doi: 10.1039/c8ra01873a. eCollection 2018 Apr 18.
Water transport in vascular plants provides remarkable opportunities for various engineering applications due to its highly efficient and powerless transportability. Several previous studies were conducted to regulate the biological responses of plants using noninvasive audible or ultrasound waves. However, the control mechanism of acoustic stimuli applied to plants has not been investigated yet. Thus, the practical application of these stimuli to real plants still exhibits technological limitations. This study experimentally investigated the effects of surface acoustic wave (SAW) frequency on plant transpiration to understand the acoustic-activated leaf transpiration and utilize the advantages of SAW. We captured consecutive images of the enhanced water transport in the test plant () by SAW at three different frequencies (10, 15, and 20 MHz). The dye solution at 15 MHz SAW presented the highest intensity value after 40 min of SAW stimulation. The excitation areas for 15 and 20 MHz SAWs were decreased to 42.3% and 22.6%, respectively, compared with that of 10 MHz SAW. The transpiration rates were directly measured to compare water transport enhancement quantitatively when different SAW frequencies were applied to the same plant leaves. The water transport in the leaves was maximized at 15 MHz SAW, regardless of excitation area.
维管植物中的水分运输具有高效且无需能量的可运输性，为各种工程应用提供了显著机遇。此前已有多项研究尝试利用无创可听波或超声波来调节植物的生物反应。然而，施加于植物的声刺激控制机制尚未得到研究。因此，将这些刺激实际应用于真实植物仍存在技术限制。本研究通过实验探究了表面声波（SAW）频率对植物蒸腾作用的影响，以了解声激活叶片蒸腾作用并利用SAW的优势。我们在三种不同频率（10、15和20兆赫）下，通过SAW拍摄了试验植物（）中水分运输增强的连续图像。在SAW刺激40分钟后，15兆赫SAW下的染料溶液呈现出最高强度值。与10兆赫SAW相比，15和20兆赫SAW的激发区域分别降至42.3%和22.6%。当将不同SAW频率应用于同一植物叶片时，直接测量蒸腾速率以定量比较水分运输增强情况。无论激发区域如何，叶片中的水分运输在15兆赫SAW下达到最大值。
