木槿幼叶培养再生植株的细胞组织学研究

以木槿(Hibiscus syriacus)幼叶为外植体,培养在附加6-BA_3+IAA(或IBA)_(0.1)+GA_(0.5)+LH_(100)的1/2MS培养基上,通过细胞组织学观察表明:接种3—10天,接触培养基的细胞体积增大,核染色加深,并移向细胞中央,有的细胞已开始分裂,接种15—20天,表皮,叶肉的栅栏细胞、海绵细胞,以及维管束附近的薄壁细胞等,都有细胞分裂,并形成愈伤组织,培养30天后,叶片结构紊乱,形成大量的分生细胞团或细胞群。同时,还有维管分子、维管组织结节,以及芽原基和叶原基的相继出现,芽原基进一步培养,形成无根苗,转移无根苗到生根培养基上,20天后,可形成完整再生植株,其结构与正常木槿植株一致。

Cytohistological Observations on Leaf Tissue Culture of Hibiscus Syriacus

The morphogenesis of plantlets regenerating from leaf explants of Hibiscus syriacus was studied by tissue culture in1/2Ms medium supplemented with 6-BA_3+IAA(or IBA)_(0.1)+GA_(0.5)+LH_(100) and by sectioning microscopy. In a period of 3-1O days of inoculation with fragmented leaves.the cells in contact with medium showed increase in volume,their nuclei became deeply colored upon staining and migrated to cell center,and some cells began to divide. In the period of 15-20 days,the palisadal and spongy cells in epidermis and mesophyll as well as the parenchymatous cells near vascular bundles divided and formed cell lumps. After 30 days of cultivation,the blade showed a disordered structure with the formation of a large quantity of parenchymatous cell masses or groups.In the same time,the vascular molecule,the vascular tissue nodes,the bud primordia and leaf primordia appeared one after another. Further cultivation of these bud primordia gave rise of buds and even of rootless seedlings. Normal plantlets regenerated 20 days after transplanting such rootless seedlings into appropriate medium for rooting. The anatomic observations on thus regenerated plantlets revealed structure identities between the plantlets regenerated from leaf explants and the normal plants of Hibiscus syriacus.