Touch induces rapid floral closure in gentians

Movement in response to mechanical perturbations in plants has long fascinated biologists and nature lovers.Rapid plant move-ments are of particular interest because they are highly recogniz-able and challenge the conventional perception that plants do not move as animals do.Good examples are predation strategies in carnivorous plants,such as sundew,Venus flytrap,and bladder-wort[1].Another well-known"sensitive plant"Mimosa pudica has leaflets that readily respond to touch,folding-up and drooping within seconds of physical disturbance[2].Such touch-response machinery in plants is thought to be shaped by the selective pres-sure from interacting animals,achieving functions of defense,dis-guise,and/or nutrient assimilation in stressful environment[1].