摘要: |
通过田间观察与石蜡切片法,对粉背薯蓣雄花的发生发育进行了形态与解剖学观察。结果表明:粉背薯蓣雄花为功能上的单性花,花芽分化时雄蕊原基正常启动,随后,3枚雄蕊正常发育,3枚雄蕊退化。成熟雄蕊药隔分叉、变宽呈加厚短叉状,退化雄蕊呈花丝状,顶端分叉或膨大成瘤状。初步分析了花部构件的演变与功能的关系。对粉背薯蓣小孢子发生及雄配子体发育过程的观察表明,花药具4个花粉囊,花药壁发育为单子叶型,由表皮、药室内壁、中层1层和绒毡层组成,绒毡层为腺质型。小孢子母细胞减数分裂后胞质分裂为同时型,四分体为四面体型排列,偶有左右对称型排列,成熟的花粉粒为二细胞型。 |
关键词: 粉背薯蓣 形态解剖 退化雄蕊 小孢子发生 雄配子体 |
DOI: |
分类号:Q944.58 |
Fund project: |
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Ontogeny of staminate flowers in D.collettii var.hypoglauca Palibin |
LI Yi1, HANG Yue-Yu2, WANG Qing-Ya1﹡, WU Bao-Cheng2,
WANG Xiao-Lu2, ZHAO Ya-Mei2
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1.College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China;2.Institute of
Botany, Jiangsu Province and the Chinese Academy of Sciences, Nanjing 210014, China
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Abstract: |
The morphological anatomy on development of staminate flowers in Dioscorea collettii var.hypoglauca was first systematically researched by means of normal paraffin embedded sectioning and observation in field. The results showed that the floral organ were imperfect. The staminate connective were forky and thicken, however,the staminodia presented filamentous with a forky or strumose apex. The evolutionary trend of flowers was discussed in this paper. The anther in D.collettii var.hypoglauca was tetrasporangiate. The anther wall was monocotyledonous type in the development, which comprised epidermis, fibrous endothecium, middle layer and glandular tapetum. The microspore mother cells underwent meiosis,and the cytokinesis was simultaneous. The tetrads were tetrahedral. Mature pollen grains were two-celled at the dispersal stage. |
Key words: Dioscorea collettii var.hypoglauca morphology and anatomy staminode microsporogenesis microgametophyte |