攀枝花苏铁种子的种皮结构及木质部管状分子研究

Study on seed coat structure and tracheary elements in xylems of Cycas panzhihuaensis L.Zhou et S.Y.Yang

对攀枝花苏铁种子的种皮进行了解剖研究,结果表明:攀枝花苏铁种子的种皮分为三层结构,由外向内依次为外种皮,中种皮和内种皮.外种皮的明显特征为含有体积很大的粘液细胞;中种皮主要由石细胞组成;成熟种子和未成熟种子的内种皮结构有明显的区别.对外种皮和内种皮木质部进行观察研究发现:外种皮和内种皮的木质部结构存在明显差异;内、外种皮木质部中均存在多种不同样式的导管分子和管胞,导管分子端壁上具单穿孔板或梯状复穿孔板.

An anatomical study on the seed coat of Cycas Panzhihuaensis had been done. The results showed that the episperm of C. panzhihuaensis includes three layers, exotesta, mesotesta and endotesta. The exotesta contains some mucus cells with great volume as its characteristics; the mesotesta was mainly composed of stone cells; the structure of endotesta of mature and immature seed was markedly different. According to the observation of xylems in the exotesta and endotesta, the structure of xylems in the exotesta and endotesta was obviously different; various patterns of vessel elements and tracheids were found in the xylems of exotesta and endotesta; the end wall of the vessel elements was simple perforation or scalariform perforation.