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以‘神湾’菠萝(Ananas comosus ‘Shenwan’)愈伤组织为材料,对体细胞胚发育过程中的形态和组织结构变化进行了观察和石蜡切片研究。结果表明,菠萝体细胞发育过程可划分为原胚、球形胚、梨形胚、笋形胚和成熟胚等5个时期。原胚是由胚性细胞分化和分裂形成的多细胞结构,呈棒状至纺锤形,最粗处直径50～200μm,灰白色,细胞较均匀一致,未出现组织分化。球形胚近球形,直径200～500μm,已开始组织分化,在后期能清楚观察到一些原维管束组织存在。梨形胚呈上细下粗的梨形,长600～1000μm,最粗处在胚体中下部(直径400～800μm),已经具备轴向性和双极性,子叶原基组织呈帽状将胚芽原始体包在其中。笋形胚似冬笋状,长1000～2 000μm,下部最粗处直径600～1000μm,后期子叶原基、胚芽鞘原基和胚芽原基已清晰可见。成熟胚长2000～4 000μm,下部最粗处直径1000～1500μm,胚芽端已具子叶、胚芽鞘、叶原基和胚芽生长点,而胚根原基分化较慢,外围有一层胚根鞘组织。胚芽和胚根内源生,子叶衣领状,第一枚叶(胚芽鞘)基部鞘状,胚轴短,叶原基呈莲座状着生在上胚轴顶端,是菠萝体细胞胚的重要特征。
Morphological and histological changes during somatic embryogenesis were observed and paraffin sections were made from the callus of ’Ananas comosus’ Shenwan’. The results showed that the development of pineapple somatic cells could be divided into five stages: primordial embryo, globular embryo, pear-shaped embryo, shoot-shaped embryo and mature embryo. The proembryo is a multicellular structure formed by the differentiation and division of embryogenic cells. The original embryo is rod-shaped to spindle-shaped with the diameter of 50 ~ 200μm in diameter. The original embryo is more uniform and homogenous with no differentiation. Spherical globular nearly spherical, diameter 200 ~ 500μm, has begun to differentiate in the late can clearly observe the existence of some of the original vascular bundle. The pear-shaped embryos are finely pear-shaped, 600-600μm in length, the thickest in the lower part of the embryoid body (400-800μm in diameter), and possess the axial and bipolar characteristics. The cotyledon primitive tissue is hat-shaped Embryo primitive package in them. Bamboo shoots shaped like winter bamboo shoots, long 1000 ~ 2 000μm, the lower part of the coarsest diameter of 600 ~ 1000μm, the late cotyledons primordia, embryo sheath primordium and germ primordia have been clearly visible. Mature embryo length 2000 ~ 4 000μm, the lower part of the thickest diameter of 1000 ~ 1500μm, the embryo has cotyledon, coleoptile, leaf primordium and germ growth point, while radicle root primordial differentiation is slow, the outer layer of radicle sheath. Embryo and radicle endogenous, cotyledons collar, the first leaf (coleoptile) basal sheath, hypocotyl short, leaf primordia were rosette-like born in the hypocotyl tip, is an important feature of pineapple somatic embryos.