屋顶长生草叶的解剖结构及其离体培养形态发生的研究

对屋顶长生草叶的解剖结构及其在离体培养条件下形态发生过程进行了研究。结果表明,屋顶长生草的叶具有肉质旱生植物叶的特点,表皮细胞外有角质层,叶有较密的腺毛分布,气孔器由两个肾形的保卫细胞和两个镰刀形的护卫细胞组成;叶肉细胞没有栅栏组织与海绵组织之分,细胞比较大,有贮水作用;维管束平行排列,导管和筛管分子都很小,为一圈维管束鞘所包围。屋顶长生草叶片离体培养形态发生途径主要有两种:一种是由外植体直接产生不定芽(器官型)途径;另一种是叶肉细胞脱分化成胚性细胞,经胚性细胞团形成愈伤组织,再分化产生芽、根等器官(器官发生型),芽分化为内起源。

Anatomic structures and morphogenesis in vitro of Sempervivum tectorum leaf

Anatomic structures and morphogenesis in vitro of Sempervivum tectorum leaf had been studied.The results show that S.tectorum is a typical xerophil.Its leaves are characterized with cutin,density glandular hair,and the stoma is composed with two kidney-shaped safeguard cells and two hook convoy cells,which effectively control the evaporation.The differentiation of palisade and sponge tissue is not visible in mesophyll structure.And the mesophyll cell is large and function as water storage.The vascular bundles distribute parallel;vessel and sieve tube are small and wrapped with vascular sheath.Plantlets formed from the leafs in vitro is inner-genetic,including organ-type morphogenesis way(plantlets directly from explants)and organogeny-type morphogenesis way(plantlets from the calli and calli from the fleshy leaves).