龙桑和垂桑胚胎发育观察及其异常现象  

Embryo Development and Abnormal Phenomena in Two Accessions of Mulberry

作　　者：巢凯翔[1] 李汉章[1] 付祖军[1] 李婵[1] 张玲丽[1] 

机构地区：[1]西北农林科技大学农学院,陕西杨凌712100

出　　处：《种子》2010年第4期23-27,共5页Seed

基　　金：西北农林科技大学大学生创新实验项目(070102007)

摘　　要：以桑科植物的两个变种龙桑与垂桑的雌株为材料(种植园内无雄株),采用常规石蜡切片法,对单性结实桑科植物的胚胎发育过程进行观察。结果表明:单性结实的垂桑和龙桑胚胎发育过程基本相似。大孢子卵细胞不经过授粉受精直接开始发育,发育成类似于合子的胚状体结构,再进行分裂,依次经棒状形、球形、心形、鱼雷形,至果实成熟时形成子叶胚。其胚珠倒生,胚囊发育类型属于蓼形胚囊,生殖方式属于二倍体孤雌生殖。在种子发育过程中发现,珠心、珠被细胞解体、大孢子卵细胞不正常分裂等异常现象。The early embryo development of mulberry varieties Longsang and Chuisang were observed by routine paraffin sections.The results showed that the development of the embryoe were almost unanimous between Longsang and Chuisang.At first the megaepore in bud began to develop without fecundation.Then developed into the cells just like zygote and then formed a stick-shaped embryo,ball-shaped embryo,heart-shaped embryo,and torpedo-shaped embryo finally.At last the embryo became mature.Some abnormal phenomena were observed during the development of the embryo,such as the disappearance of nucellar and integument,the abnomal division of megaepore.

关 键 词：桑树 胚胎发育 单性结实 解剖 

分 类 号：S184[农业科学—农业基础科学]