Cytokinin (CTK) is a plant hormone isolated or synthesized from corn or other plants. Generally produced in the roots of plants, it is a substance that promotes cytokinesis and promotes the differentiation and growth of various tissues. It has synergistic effect with auxin. It is a plant hormone that regulates the growth and development of plant cells. It plays an active role in cell division, and also participates in cell growth and differentiation and other related physiological activities, such as kinetin (KT), zeatin (ZT), 6- benzylaminopurine (6-BA) and so on.