机构地区: 暨南大学
出 处: 《植物学通报》 2003年第1期90-93,共4页
摘 要: 本文对水蔗草的胚珠附器进行研究 ,结果表明 :在功能大孢子时期 ,珠孔端的 1~ 3个珠心细胞开始特化 ,发育成胚珠附器 ;胚珠附器发生时 ,有些胚珠同时出现无孢子生殖原始细胞 ;有性生殖和无孢子生殖的胚囊中均有胚珠附器存在 ;但在无孢子生殖的胚囊中 ,胚珠附器一般很大 ,长约是宽的 1~ 3倍 ;而有性生殖胚囊的胚珠附器的长约是宽的 1~ 2倍 ;和有性生殖胚囊相比 ,无孢子生殖胚囊的胚珠附器更加发达 ;存在发达的胚珠附器是水蔗草无孢子生殖胚囊的特点之一。 Embellum of Apluda mutica was studied by light microscope. It was demonstrated that outer layer of 1_3 nucellar cells which enlarge in size and often protrude into the micropyle to form embellum at the functional megaspore stage. Both polygonum type and panicum type embryo sac have embellum. The length of embellum is about one to three times of its width in mature aposporous embryo sac, while its length is one to two times of its width in mature sexual embryo sac. The mature embellum cells in aposporous embryo sac were larger than that in sexual embryo sac. The larger embellum could be used as a secondary screening indicator for identifying aposporous embryo sac in Apluda mutica.