柠条锦鸡儿小孢子发生和雄配子体发育

利用常规石蜡切片技术对柠条锦鸡儿小孢子发生及雄配子体发育的过程进行了观察,为柠条锦鸡儿生殖生物学提供基础资料。结果表明:(1)柠条锦鸡儿雄蕊花药4室,花药壁完全分化时,由外到内依次是表皮、药室内壁、中层和绒毡层,花药壁发育为基本型;表皮细胞1层,发育过程中始终存在;药室内壁在花药成熟时形成带状纤维层加厚;幼小花药壁的中层1～2层细胞,在花药发育成熟时退化消失;绒毡层1层细胞,腺质绒毡层,花药成熟时消失。(2)小孢子母细胞减数分裂过程中的胞质分裂为同时型,产生四面体型和左右对称型小孢子。(3)成熟花粉粒为二细胞型,扫描电镜下观察其成熟花粉粒为圆球形,外壁近光滑。(4)花粉母细胞分裂后形成的四分体小孢子中出现多核仁现象,核仁数在2～6个范围变化,推测这可能和末期Ⅱ核仁融合的不彻底有关。研究发现,柠条锦鸡儿小孢子发生和雄配子发育过程没有发现异常现象。

Microsporogenesis and Male Gametophyte Development of Caragana korshinskii Kom.

Microsporogenesis and male gametophyte development of Caragana korshinskii Kom.were observed by traditional paraffin sections.The results showed that:(1)The anther had four chambers;the development of anther wall was the basic type,which consisted of epidermis,endothecium,middle layer and tapetum.The epidermis consists of one layer of cells and still existed as the anther matured.The endothecium developed banding-shaped thickenings when the anther matured.The young anther wall had 1~2 cell middle layer and degenerated when maturity of the anther,the tapetum was of glandular type.(2)Cytokinesis occurred simultaneously with meiosis in a microspore mother cell,and the tetrads were mostly tetrahedral while some were symmetrical.(3)The mature pollen grain was of binuclear type.With scanning electronic microscope(SEM),the mature pollen grains were observed,which appeared spherical in shape,and the exine was almost smooth.(4)Some of the tetrads generated by microspore mother cell had more than one nucleolus whose number changed from two to six,it may relate to the incomplete fuse of nucleolus in telophase two.These results suggested that microsporogenesis and male gametophyte development of C.korshinskii Kom.were normal.These observed results provided base materials for the reproduction biology and provided theoretical ground for exploitation and utilization of C.korshinskii Kom.