大豆体细胞胚胎发生系统组织学研究

大豆体细胞可以诱导发生在形态和结构上类似胚结构的胚状体。利用大豆体细胞胚发生系统进行大豆遗传转化，具有转化频率高、同步性好、转基因植株嵌合体少等诸多优点。对经根癌农杆菌侵染后，在含卡那霉素筛选培养基上生长的大豆未成熟子叶胚性细胞的发生、分化及发育进行了组织学研究。结果表明，体细胞胚以非芽体方式发生。胚性细胞可以从外植体表层或表层下1-2层细胞开始发生。随着胚性细胞的分裂，周围细胞开始退化解体，并形成具有类似胚柄结构的胚状体。之后，呈球形的胚状体突出于表皮之外，并依次发育成心形胚、鱼雷形胚和子叶形胚。以期为利用大豆未成熟子叶诱导体细胞胚发生系统高效转化体系的建立提供理论依据。

Histological Study on Somatic Embryogenesis for the High-efficiency Transformation of Soybean

Embryoids with embryo-like structure can be induced from soybean somatic cells. Transformation of soybean through somatic embryogenesis possesses many advantages, such as higher efficiency, better synchronism, and lower chimerism, over other recipient systems. In this paper, we conducted histological inves- tigations on initiation, differentiation and development of soybean dons cultured on the selection medium containing kanamycin after The results showed that the somatic embryloids were generated embryogenic cells of the immature cotyle- infection with Agrobacterium tumefaciens. through the non-shooting way. The embryogenie ceils initiated at first from the cells of epidermis and 1 -2 layers of subepidermis of the immature cotyledons. With division of these embryogenic cells, the cells around degraded and suspensor-like ceils mass appeared. The globular embryoids eventually extruded out of the epidermis of the explants, and devel- oped into heart-shaped, torpedo-shaped and cotyledon-shaped embryoids consequently. Our study might provide some insight into the mechanism for high-efficiency transformation through somatic embryogenesis of the immature cotyledons of soybean.