Abstract:The characteristics of phototropism in maize coleoptiles were studied by insertinga ndca piece into coleoptile and using HPLC analysis. The results showed that ndca piececould not stop phototropic movement of maize coleoptiles, though it could prevent thetranslocation of auxin. The coleoptile could bend to grow sindlarly to phototropism whenits one side was injured by a razor blade. Bending growth of the coleoptiles was alsofound when a piece of agar containing injurant which was extracted from injuredcoleoptile, was placed on unilateral side of coleoptile with tip excised HPLC analysisindicated that the inhibiting substance produced during the induction by blue light or bymechanical iaiury was 6methoxy-2-benzoxazolinone (MB).
