The biological significance of leaf-movement, an approach using a synthetic inhibitor of leaf-closure

Nyctinastic leaf-movement, which is folding and opening movement of the leaves according to circadian rhythm, have been widely observed in leguminous plants. Although this movement has been known since the age of Alexander the Great, the question ‘Why does leguminous plant sleep?’ has always puzzled many scientists studying nyctinasty. We have revealed that nyctinastic leaf-movement is essential for the survival of leguminous plants by inhibiting leaf-movement using synthetic leaf movement inhibitor. Leguminous plant will wither and die without nyctinasty. Our result gives an important clue for the historic mystery, ‘Why does the leguminous plant sleep?’