【摘要】 研究绵刺 (Potaniniamongolica)的胚胎发育过程 ,首次报道其有性生殖模式为无融合生殖的体细胞无孢子生殖 (Apospory) ,由合点端珠心细胞形成 3～ 7个无孢子孢原 ,孢原细胞体积增大 ,形成单核胚囊 ,后经 3次有丝分裂形成多个八核七细胞的成熟胚囊 ,胚囊发育属山柳菊型。但一般只有一个胚囊可发育出成胚。胚囊发育过程中具极性 ,由合点端向珠孔端延伸。未观察到有性生殖胚囊的发育。更多还原

【Abstract】 Embryology of Potaninia mongolica is studied in this paper. The results firstly show that the mode of reproduction conforms to apospory. Three to seven aposporous archespores are developed from nucellar cells in chalazal end. The archespores increase and form uninuclear embryo sac, which undergoes three mitoses to form several eight-nucleated mature embryo sac as Hieracium type. But embryo is developed from only one embryo sac. Development of aposporous embryo sacs shows polarity, which extend from micropylar end to chalazal end. No normal sexuparous embryo sac is found.更多还原