空心莲子草雄蕊和雌化雄蕊发育的比较研究

Comparative study on the development of stamen and feminisation stamens of Alternanthera philoxeroides

关键词:  空心莲子草  雄蕊  雌化雄蕊

Key words:  Alternanthera philoxeroides  stamen  Feminisation stamen

摘要:

采用形态解剖和石蜡切片法，对空心莲子草雄蕊和雌化雄蕊的形态和结构的发育过程进行了观察。结果显示：（1）在形态上，空心莲子草两性花雄蕊由聚药雄蕊和无药雄蕊构成，二者相间而生成一轮；而空心莲子草雌化雄蕊花的雌化雄蕊由雌化雄蕊和无药雄蕊构成，雌化雄蕊的外形如雌蕊状，其外轮为无药雄蕊，二者前后对应而生，成二轮；（2）在结构上，空心莲子草两性花雄蕊的每个花药具两个花粉囊，花药壁由表皮、药室内壁、中层和绒毡层组成，花粉母细胞减数分裂形成的四分体有四面体型和左右对称型，成熟花粉粒为3核，但后期大量解体，新鲜花粉粒经生活力测定无活性；雌化雄蕊花雌化的雄蕊有柱头、花柱和子房，但子房室内无胚珠状结构，仅为一个空腔。

Abstract:

The morphology structure development of stamen and feminisation stamen of Alternanthera philoxeroides were observed by the methods of morphology anatomy and paraffin section. The results showed that:(1)In the morphology，stamen of bisexual flower of A.philoxeroides consisted of staminodium and synantherous stamen，which were interval in a wheel；while feminisation stamen of feminisation stamen flower of A.philoxeroides consisted of staminodium and feminisation stamen，which looked like pistil，staminodium beside the feminisation stamen in the outer wheel. (2)In the structure，each anther of bisexual flower of A.philoxeroides had two pollen sac，and the anther wall was composed of four layers:epidermis，endothecium，middle layer and tapetum. The tetrads were formed in meiosis of pollen mother cells，which shaped 〖JP3〗as tetrahedral and bilateral symmetry. The mature pollen was of 3 celled types，which disintegrated at the post maturation stage. Fresh pollen had no activity through viability determination；feminisation stamen of A.philoxeroides were composed of stigma，style and ovary，however, the locule had no ovule，just a cavity.