Formation of tendril coiling and spring constant of coiled tendrils of climbing plants

摘要

Some plants whose stems lack the strengthening tissues to maintain the plant in an upright position, support themselves by means of thin appendages called tendrils that grasp onto objects they encounter. The tendrils of some species coil after tactile simulation. The coils have reverse coiling points where the coiling direction is reversed. This differs from normal springs used in the field of industry. This study deals with observation of the formation of tendril coiling using a video camera, and evaluation of spring constants of coiled tendrils of some species using tension tests and the finite element analysis. The results showed that reverse coiling points play an important role to form tendril coil, and the spring constants varied with increase of elongation of coils.