Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 08, 2019 - September 11, 2019
The flower of the Stylidium has stamens and a style fused into a single column. When the flower is stimulated, the column flips rapidly through an angle of 270–300 degrees in 10–30 ms, depending on species. After this high-speed rotation called "firing", the column slowly resets to its original position in 200–600 s. More than forty years ago, a mechanical model of the Stylidium's column was proposed in which "firing" was caused by changing turgor pressure, but this model could not explain the movement of ions in the bending part of the column. We focused on a oscillatory movement of the column whose laballum had been removed. In this study, how the contact between the column and the labellum plays a role in the firing movement was investigated by blocking this contact with alminum foil and the others. From the results of these experiments, we attempted to explore the mechanism of the high-speed rotation of the column by proposing a new mechanical model of the column. Furthermore, we observed the surface of the column and the labellum by using SEM (Scanning Electron Microscope) to find out some evidence of adherence in the column which was shown in the blocking experiments.