杜仲叶片和叶柄愈伤组织的诱导和植株再生

本实验以5~6年生杜仲叶片及叶柄为外植体,研究了杜仲愈伤组织诱导及植株再生的方法。结果表明:接种于补加NAA(2.0~4.0 mg/L)或BA(1.0 mg/L)+NAA(2.0~4.0mg/L)的MS培养基上的叶片和叶柄,经21~28d培养后,脱分化形成绿色或浅绿色致密愈伤组织,频率达到70%以上。绿色致密愈伤组织在补加BA(2.25~2.75 mg/L)+NAA(0.15 mg/L)的MS培养基上经过1~2次继代之后,即出现茎芽分化,频率在15%以上,只是其中许多都是畸形苗,正常苗频率较低。此问题尚在研究之中。选择生长健壮的再生植株,切除其基部愈伤组织,然后将切口浸泡在250mg/L无菌ABT生根粉溶液中3~5sec,再插入1/4强度无激素MS培养基中, 2~3周后,在苗基部长出1~3条白色粗壮的不定根,生根频率在60%以上。

CALLUS INDUCTION AND PLANT REGENERATION FROM LEAVES AND PETIOLE IN E.ULMOIDES

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.