水杉愈伤组织诱导及植株再生

通过愈伤组织诱导器官发生途径, 建立了水杉(Metasequoia glyptostroboides)的植株再生体系, 探讨了不同外植体 (种胚、幼叶切块、茎段、根段)和植物生长调节剂对不定芽直接再生和愈伤组织诱导器官发生的影响。结果表明: 以种胚、无菌苗叶片、茎段和根作为外植体, 在MS补加2,4-D、NAA和6-BA不同组合的培养基上都能诱导得到愈伤组织, 其中种胚诱导愈伤组织效果最好, 诱导率可达100%, 茎诱导效果次之, 诱导率为97.1%。诱导愈伤组织效果较好的培养基有:MS+1.0 mg·L^–1 2,4-D + 0.5 mg·L^–1 6-BA、MS + 0.1 mg·L^–1 6-BA + 1.0 mg·L^–1 NAA、MS + 0.5 mg·L^–1 6-BA+1.0 mg·L^–1 NAA、MS+1.0 mg·L^–1 6-BA+1.0 mg·L^–1 NAA、MS+0.5 mg·L^–1 6-BA+2.0 mg·L^–1 NAA、MS+1.0 mg·L^–1 6-BA + 2.0 mg·L^–1 NAA和MS + 0.5 mg·L^–1 2,4-D + 0.5 mg·L^–1 NAA。以愈伤组织在MS培养基上植株再生效果最好, 再生率为62.5%。

Callus Induction and Plant Regeneration of a Living Fossil, Metasequoia glyptostroboides

We optimized a rapid, effective system of plant regeneration by direct shoot regeneration and organogenesis in an endangered tree, the living fossil Metasequoia glyptostroboides. We studied the influence of plant growth regulators on explant types (embryo, root, stem and young leaf). Callus could be induced by different types of explants on MS medium supplemented with different combinations of 2,4-D, NAA and 6-BA. The frequency of callus induction was highest (100%) with  embryo used as explants, then with stem (97.1%). The best media for callus induction on embryo was MS+1.0 mg·L^–1 2,4-D+0.5 mg·L^–1 6-BA, MS+0.1 mg·L^–1 6-BA+1.0 mg·L^–1 NAA, MS+0.5 mg·L^–1 6-BA+1.0 mg·L^–1 NAA, MS+1.0 mg·L^–1 6-BA+1.0 mg·L^–1 NAA, MS+0.5 mg·L^–1 6-BA+2.0 mg·L^–1 NAA, MS+1.0 mg·L^–1 6-BA+2.0 mg·L^–1 NAA and MS+0.5 mg·L^–1 2,4-D+0.5 mg·L^–1 NAA. More regenerated plants were obtained on MS medium, with a frequency of 62.5%.