Embryogenesis of Polyembryonic Rice ApⅢ: Structural and Histochemical Studies of Egg Apparatus Around Fertilization  

多胚水稻ApⅢ的胚胎发生:受精前后卵器的结构和组织化学研究(英文)

作　　者：母锡金[1] 朱至清[1] 蔡雪[1] 孙德兰[1] 林金星[1] 

机构地区：[1]中国科学院植物研究所,北京100093

出　　处：《Acta Botanica Sinica》2002年第12期1387-1395,共9页Acta Botanica Sinica（植物学报：英文版）

基　　金：中国科学院院长基金 ;国家自然科学基金 (3 970 0 0 0 8)~~

摘　　要：The structural and histochemical changes of the egg apparatus in the polyembryonic rice ( Oryza sativa L.), ApⅢ with the highest frequence of additional embryos among the polyembryonic rice investigated, before and after fertilization were studied and compared with those of normal and other polyembryonic rices in a similar developmental period. A total of 2 932 ovules were observed and each of them contained only a single embryo sac with a set of egg apparatus. Among 1 655 embryo sacs, there were 1 643 embryo sacs (99.27%) with one normal egg apparatus in each embryo sac, and only 12 embryo sacs (0.73%) from the remainder with 4_celled egg apparatus, i.e. two eggs and two synergids. Neither the numerous poly_egg apparatus and egg_like cells, nor the double set of embryo sacs each containing one egg apparatus and other abnormal egg apparatus in single ovary, which were reported by earlier investigators to have high frequency of embryo production in SB_1 and ApⅣ, were observed. The egg cell was located at the subterminal site of the micropylar end of embryo sac. The cytoplasm of egg cell was rich in protein materials and polysaccharide grains, which did not disappear until the division of zygote. The prominent nucleus was closely surrounded by protein and polysaccharide grains, which did not disappear until the division of zygote. No cytological difference was found between egg cells from the normal and abnormal egg apparatus. The two synergids were fully developed and situated at the upper most part of the micropylar end of the mature embryo sac. In most embryo sacs, the synergids were flask_shaped with longer necks, and a widened cap_shaped top, in close contact with the micropyle. The synergids had a well developed filiform apparatus. The characteristic appearance of the filiform apparatus as well as the cap_neck region of synergids before and after pollen tube penetration were easily distinguishable from the egg cell. The structure, the stainability with Coomassie Brilliant Blue and PAS reaction, the pro对高频率多胚水稻 (OryzasativaL .)ApⅢ受精前后卵器的细胞结构和组织化学变化进行了观察 ,并同已报道的正常水稻和多胚水稻大至相同发育时期的卵器进行了比较 ,结果表明 :ApⅢ的 2 932个幼嫩子房中 ,每个子房只有一个胚囊。没有看到含有一对胚囊和每个胚囊里有一套卵器的现象。除解体的和含胚的胚囊外 ,16 5 5个胚囊中 ,含 1个卵细胞和 2个助细胞组成的正常卵器为 16 4 3个 (99.2 7% ) ,含 2个卵细胞和 2个助细胞的 4细胞卵器为 12个 (0 .73% )。没有观察到大量 4细胞卵器、5细胞卵器 (即由 3个卵细胞和 2个助细胞组成 )和卵状细胞 ,以及其他 4卵、5卵卵器的变异类型。卵细胞位于对着子房壁维管束一侧。细胞质含丰富的蛋白质和多糖颗粒 ;细胞核位于细胞中下部 ,少有偏远轴端的 ,直到合子分裂前由蛋白质物质和多糖颗粒聚成的环所包裹。成熟胚囊中常见2个助细胞。助细胞位于珠孔端靠子房壁维管束一侧 ,多数为长颈烧瓶状 ,少有长形和星月形的。其珠孔端壁内侧丝状器发达 ,细胞质的结构 ,蛋白质物质和多糖颗粒的积累、分布及消长 ,细胞核的大小、组织化学反应和周围物质的动态与卵细胞的相同。此外 ,ApⅢ的 2个助细胞存留时间较长。当花粉管进入助细胞的早期 ,助细胞的丝状器和帽颈端被花粉管损伤 。

关 键 词：polyembryonic rice egg apparatus embryo sac apogamety REPRODUCTION 

分 类 号：S511[农业科学—作物学]