Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Hyoja Dong, Nam-Gu, Pohang, Gyeongbuk, 790-784, Korea; School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Hyoja Dong, Nam-Gu, Pohang, Gyeongbuk, 790-784, Korea; Center for Biofluid and Biomimic Research, Pohang University of Science and Technology (POSTECH), Hyoja Dong, Nam-Gu, Pohang, Gyeongbuk, 790-784, Korea.
Microsc Res Tech. 2013 Nov;76(11):1204-12. doi: 10.1002/jemt.22286. Epub 2013 Sep 12.
Mimosa pudica has three distinct specialized organs, namely, pulvinus, secondary pulvinus, and pulvinule, which are respectively controlling the movements of petioles, leaflets, and pinna in response to external stimuli. Water flow is a key factor for such movements, but detailed studies on the organization of the vascular system for water transport in these organs have not been published yet. In this study, organizations of the xylem vessels and morphological features of the pulvinus, the secondary pulvinus, and the pulvinule were experimentally investigated by X-ray computed tomography and histological technique. Results showed that the xylem vessels were circularly distributed in the specialized motile organs and reorganized into distinct vascular bundles at the extremities. The number and the total cross-sectional area of the xylem vessels were increased inside the specialized motile organs. Morphological characteristics obtained in this study provided new insight to understand the functions of the vascular networks in the dynamic movements of M. pudica.
含羞草具有三个独特的特化器官，即叶枕、次叶枕和小叶柄，分别控制叶柄、小叶和羽片对外界刺激的运动。水流是这些运动的关键因素，但尚未有关于这些器官中用于水分运输的维管束组织的详细研究。在这项研究中，通过 X 射线计算机断层扫描和组织学技术，对叶枕、次叶枕和小叶柄的木质部导管组织和形态特征进行了实验研究。结果表明，木质部导管呈圆形分布在特化的运动器官中，并在末端重新组成明显的维管束。特化运动器官内部的木质部导管数量和总横截面积增加。本研究获得的形态特征为理解含羞草动态运动中血管网络的功能提供了新的见解。
