中国水稻科学

中国水稻科学

• 研究报告 •    下一篇

同源四倍体水稻胚乳发育:极核融合和胚乳细胞化

王 兰1; 刘向东1，*; 卢永根1; 冯九焕1; 徐雪宾1; 徐是雄2   

  1. 1华南农业大学 广东省植物分子育种重点实验室， 广东 广州 510642； 2香港大学 植物系， 香港薄扶林道
  • 收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2004-07-10 发布日期:2004-07-10

Endosperm Development in Autotetraploid Rice:The Fusion of Polar Nuclei and the Formation of Endosperm Cell Wall

WANG Lan1; LIU Xiang-dong1; *; LU Yong-gen 1; FENG Jiu-huan 1; XU Xue-bin 1; XU Shi-xiong(S. Y. Zee)2   

  1. 1Guangdong Provincial Key Laboratory of Plant Molecular Breeding; South China Agricultural University; Guangzhou 510642; China; 2Department of Botany; the University of Hong Kong; Pokfulam Road; Hong Kong;
  • Received:1900-01-01 Revised:1900-01-01 Online:2004-07-10 Published:2004-07-10

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被引次数

61

摘要： 利用激光扫描共聚焦显微术和塑料包埋半薄切片技术观察同源四倍体水稻极核融合及游离核进一步发育的过程，发现同源四倍体水稻约有1/3子房极核融合过程和游离核进一步发育与其二倍体原种的基本一致；2/3子房出现各种异常现象，如极核未受精、受精异常和胚乳游离核发育滞后等。应用荧光增白剂染色对胚乳细胞化过程进行观察，直接观察到胚乳初生壁的出现和形成过程以及不同部位的胚乳细胞壁的形成机理。表明同源四倍体水稻与二倍体水稻胚乳的细胞化过程基本一致，胚乳细胞初始垂周壁来源于珠孔端胚囊壁内突向心游离生长，初始平周壁来源于游离核有丝分裂产生的成膜体，而中间胚乳细胞壁则有些来源于游离核有丝分裂产生的成膜体，有些是自由生长而来。同源四倍体水稻胚乳细胞化过程也出现相当比例的异常现象，如无细胞壁形成、细胞化不同步和产生分枝状的细胞壁等。同源四倍体水稻胚乳发育过程中出现的极核融合、游离核发育和细胞化过程等异常都可能导致同源四倍体水稻的结实率降低。

关键词: 水稻, 同源四倍体, 胚乳发育, 激光扫描共聚焦显微术, 荧光显微术

Abstract: By using the laser scanning confocal microscopy and plastic (Leica 7022 histeresin embedding kit) semi thin sectioning technique, comparative studies on the fusion of polar nuclei and the formation of the wall of endosperm cells in autotetraploid and diploid rice were carried out. Two types of ovaries were observed in the autotetraploid. One type displayed normal process of polar nuclei fusion and further development of free nuclei similar to those in ovaries in the diploid. The other showed many kinds of abnormal development of polar nuclei, including non fertilization, single fertilization, polar nuclei fusion without mitosis and non synchronization of endosperm nuclei. The development of endosperm cell wall in autotetraploid was the same as that in diploid. The wall ingrowths of embryo sac near the micropylar end produced walls of endosperm cell firstly vertically at right angle to the embryo sac wall. These walls ran parallel to each other initially and extended towards the endosperm. As to the cell wall situated in the middle of the endosperm, some of them originated from phragmoplast, but others appeared to have originated randomly without the formation of an obvious phragmoplast. Some abnormal ovaries were found in autotetraploid and they all showed abnormal cell wall development in their endosperm. Abnormal fertilization of polar nuclei and further development of endosperm may cause the decrease of seed set in autotetraploid rice.

Key words: rice, autotetraploid, endosperm, laser scanning confocal microscopy, fluorescence microscopy