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Plant Diversity ›› 2008, Vol. 30 ›› Issue (05): 549-556.DOI: 10.3724 SP.J.1143.2008.07292

• 研究论文 • 上一篇    下一篇


赵兴峰1 , 2 , 孙卫邦1, 杨华斌3 , 李万成4   

  1. 1 中国科学院昆明植物研究所昆明植物园, 云南昆明 650204 ; 2 中国科学院研究生院, 北京 100049; 3 文山州林业局种苗站, 云南文山 663000; 4 广西德孚自然保护区, 广西百色 533000
  • 收稿日期:2007-12-13 出版日期:2008-10-25 发布日期:2008-10-25

Mega- and Microsporogenesis and Development of Female and Male
Gametophytes of Michelia coriacea (Magnoliaceae), a Globally Critical Endangered Plant in South-East Yunnan of China

ZHAO Xing-Feng1 , 2 , SUN Wei-Bang1, YANG Hua-Bin3 , LI Wan-Cheng4   

  1. 1 Kunming Botanical Garden , Kunming Institute of Botany , Chinese Academy of Sciences, Kunming 650204 , China; 2 Graduate University of Chinese Academy of Sciences, Beijing 100049 , China ; 3 The Seedling Station of Wenshan Forest Bureau , Wenshan 663000 , China ; 4 Defu Nature Reserve, Baise 533000 , China
  • Received:2007-12-13 Online:2008-10-25 Published:2008-10-25

摘要: 用石蜡切片法对极度濒危植物西畴含笑( Michelia coriacea) 的大小孢子发生和雌雄配子体发育过程进行观察。西畴含笑的花药为四囊型, 花药壁5~7 层, 腺质绒毡层; 小孢子形成时胞质分裂方式为修饰性同时型; 四分体排列方式多为四面体型和十字交叉型, 偶为不规则形状; 成熟花粉粒为二细胞型。西畴含笑的胚珠倒生, 双珠被, 厚珠心; 大孢子母细胞减数分裂形成线形四分体, 合点端大孢子为功能大孢子, 胚囊发育类型为蓼型。西畴含笑胚胎学特征与木兰科多数种类一样, 均表现出胚胎发育的原始性。西畴含笑大小孢子发生和雌雄配子体发育过程中存在严重异常发育特征, 这可能是导致其结实率低的重要原因。

关键词: 西畴含笑, 大小孢子发生, 配子体发育, 败育, 极度濒危

Abstract: The mega- and microsporogenesis and development of male and female gametophytes of Michelia coriacea were investigated using paraffin section method . The anther of the species was tetrasporangiate and its anther wall was composed of 5 - 7 layers cells, and the tapetum belonged to glandular type. In the meiosis of microsporocyte, cytokinesis was modified simultaneous type. The tetrads were tetrahedral, decussate and sometimes were anomalous type. Mature pollen grain was twocelled. The ovule was anatropous, bitegmic, and crassinucellar. The megaspore mother cell undergone meiotic divisions and developed into a linear type of tetrads. The chalazal megaspore of the tetrad was functional. The functional megaspore underwent three successively nuclear divisions to give rise to eight-nucleate embryo sac which was Polygonum Type. The high percentage of abortion could be observed in process of megaspore and microspore genesis and the development of gemetophytes. The abnormality in the reproductive development of this species might be the main cause of its extremely low seed set .

Key words: Michelia coriacea