Herbal Extract Supplier. Indoleacetic acid is a common natural auxin in plants. Indoleacetic acid can promote the top bud tip formation of plant branches, buds and seedlings. Indole-3-Carbinol precursor is tryptophan. Indoleacetic acid is a plant auxin auxin with many physiological effects, which is related to its concentration. At low concentration, it can promote growth, at high concentration, it can inhibit growth and even cause plant death. This inhibition is related to whether it can induce ethylene formation. The physiological effects of auxin are manifested in two levels. At the cellular level, auxin can stimulate the cell division of cambium; stimulate the cell elongation of branches and inhibit the growth of root cells; promote the differentiation of xylem and phloem cells, promote the hairy roots of cuttings and regulate the morphogenesis of callus. At organ and plant level, auxin plays a role from seedling to fruit maturity. Auxin can control the reversible red light inhibition of hypocotyl elongation in seedlings; when indoleacetic acid is transferred to the lower side of the branch, Mangifera Indica Extract will produce the geotropism of the branch; when indoleacetic acid is transferred to the backlight side of the branch, 4-Dihydroxybenzeneacrylic Acid will produce the phototropism of the branch; indoleacetic acid causes the apical dominance; it can delay leaf senescence; auxin applied to the leaf can inhibit abscission, while auxin applied to the proximal end of the abscission layer can promote abscission; auxin Auxin can promote flowering, induce the development of unisexual fruit and delay the ripening of fruit.