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A series of attempts to select optimum types and concentrations of growth regulators were carried out to induce callus, shoot, and root formation using individual cytokinins and auxins. Apical meristems cultured on MS medium with auxins alone or the combinations of auxin and cytokinin were not effective on multiple shoot formation, but caused rapid callus and root formation. After 60 days of culture, some explants developed into shoots together with calli at low frequency. However, the media supplemented with cytokinins alone were the most effective on multiple shoot formation without callus induction. Among cytokinins tested, BA and kinetin were more efficient than zeatin for shoot multiplication. Thus, the best results for multiple shoot formation were obtained when kinetin or BA at 0.2-1.0 ㎎/L was added to the medium. After apical meristems were cultured on medium with 1.0 ㎎/L BA for 60 days in primary culture, multiple shoot with 8.2 shoots/explant were obtained. Plantlets divided into small parts from multiple shoot gave rise to 3-4 well-developed shoots with 4-5 true leaves in every 2 months. Rooting and root growth was the most effective on MS medium with 0.01 ㎎/L IBA. After rooting, regenerated plants were washed and transferred to pots containing sterilized soil.
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