中间锦鸡儿(Caraganaintermedia)的大小孢子和雌雄配子体发育

(1)孢原为单细胞,发生于表皮之下,大孢子排列为直线型·合点端大孢子为功能大孢子;(2)珠柄、珠被、合点和珠孔端的珠心细胞中具多糖.孢原、造孢、母细胞和四分大孢子阶段近珠孔的珠心细胞中具少量淀粉粒.一旦功能大孢子分化,合点和珠孔端细胞中多糖增加.从单棱胚囊分化至二核胚囊时,珠孔端细胞中多糖增加;(3)受精前,极核融合为次生核,周围富含淀粉粒,助细胞解体一个成熟卵中极性明显;(4)小孢子孢原为多细胞,药壁为基本型,具腺质绒毡层;(5)减数分裂Ⅰ开始,在花粉母细胞之间出现肼胝质壁.一直到四分孢子时全部形成肼胝质壁使与二倍体的药壁隔离.胞质分裂属同时型,四分小孢子为四面体型;(6)小孢子第一次有丝分裂为不等分裂,形成一个较小的半球形的生殖细胞和一个较大的营养细胞.生殖细胞发育中存在暂短的细胞壁,其成分未定.成熟花粉粒为二细胞型,园形、具三孔沟;(7)孢原和造孢细胞以及相应阶段的药壁细胞中均具可溶性蛋白质,从单棱花粉粒开始,绒毡层细胞中多糖和蛋白质并存.早期小孢子和发育中的小孢子中均具多糖.成熟花粉粒中多糖和蛋白质并存.

Development of the Mega-and Microspore and Male and Female Gametophytes in Caragana intermedia

(1)Archesporium is one of cell.Arrangement of megaspore is linear shaped.The megaspore of cha- lazal end.is functional megaspore.(2) Polysaccharides in the cells of funicle,integument,micropylar and chalazal end,during the stages of archesporium,sporogenous Mines and megaspores.The cells around the micropylar end have a little of starch gains.The polysaccharides in the cells of micropylar and chalazal end increases with the formation of functional megaspore.It also increases when one nuclear embryo sac devel- ops to two nuclear embryo sac.(3)Before fertilization the polar nuclei fuse and form to secondary nucleus. Its round areas are rich in starch grains.One of the synergids degenerates.The polarity in the mature egg is prominent(4)Microspore archesporium is of multicellular,the anther wall conforms to basic type,and the tapetum is glandular.(5)At the beginning of meiosis I callose wall appear to present between the Pmcs (pollen mother cells)up to the tetrad stage all the callose wall are formed.At this time,the Pmcs are iso- lated with the 2N anther wall.The cytokinesis conforms to simultaneous type,the microspore tetrad is te- trasheral type.(6)The first mitosis of microspore is inequal,which produce a smaller himisperical genera- tire cell and a larger vegetative cell.During the development of generative cell,the cell wall exists tempo- rarity.Its compoment is not certainly.The mature pollen grain is 2-celled type,spherical and 3-colporate. (7)The soluble proteins present in the cells of anther wall as well as in the archeporial and sporogenous stages.Beginning from the one nuclear pollen grain polysaecharoses presents in the tapetal cells together with proteins.There is polysaccharide in both early and developly microspores.The polysaccharoses present in the mature pollen grain accompary with proteins.