Significance of Thigmotropism?

Question

what is the significance of thigmotropism?

i.e. reaction of Mimosa pudica/ the sensitive plant

Answer 1

Mimosa pudica has a thigmonastic movement not thigmotropic. The leaf closure is fast, non directional, reversible, and contact trigged the same as the Venus Fly Traps response. There is a leaf motor organ called a pulvinus in the petiole. This organ alters shape with turgor changes so is reversible unlike tropic movement that involves permanent hormone regulated growth.

http://www.bookrags.com/wiki/Thigmonasty

http://www-saps.plantsci.cam.ac.uk/recor...

Leaf opening control molecule is now isolated - mimopudine.

http://www.sciencedirect.com/science?_ob...

Nastic movements are all defensive or protective in function.  Thigmonastic movements avoid herbivores and heavy storm damage. Nictinastic, closure at night, avoids nocturnal herbivores, slows dessication further in dry spells because leaves will close even in day if dessication causes turgor loss.

Answer 2

if a browsing animal tries to eat it, the leaflets fold up in response to contact.