关键词: 杜仲, 愈伤组织诱导, 植株再生

Abstract: In order to establish somaclones of E. ulmoides, we used as explants leaves and petioles of 5~6 year old E. ulmoides and studied the method of callus induction and plant regeneration. Explants taken from leaves and petioles were cultured on MS medium supplemented with 2.0~4.0 mg/L NAA or 1.0 mg/L BA+2.0~4.0 mg/L NAA. After 21~28 days of culture both leaves and petioles dedifferentiated, forming green or greenish compact callus, with induction frequency surpassing 70%. Transferred onto MS medium supplemented with 2.25~2.75 mg/L BA+0.15 mg/L NAA and cultured for 1~2 passages, the callus redifferentiated at a frequency of over 15%. The optimal condition for redifferentiation needs further study because many shoots went abnormal. To induce rooting, healthy shoots were selected. The callus at the based end of the shoot was cut off, and the cut end was soaked in a sterile ABT rooting powder solution (250 mg/L) for 3~5 sec. Subsequently the treated shoot was transplanted into 1/4 strength, hormone free MS medium. After 2~3 weeks, 1~5 sturdy white root(s) appeared from the lower end of the shoot. Approximately 60%~80% of the shoots rooted.