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采用压片法观察研究了红皮云杉花粉母细胞(PMC)减数分裂和花粉发育的完整过程,证实红皮云杉PMC减数分裂始于每年春季,持续时间2～3个月。减数分裂中期二价体构型以两臂至少发生两次交换的环形二价体居多,很少观察到棒状二价体。减数分裂粗线期结束之后经历明显的弥散双线期阶段。胞质分裂发生在第二次减数分裂结束之后,属于同时型分裂方式,形成的四分体主要是四面体形。四分体的构型还受到第二次减数分裂中期纺锤体定向的影响,其中纺锤体垂直排列形成的四分体为四面体形,而纺锤体平行排列形成的四分体为四角形。四分体在胼胝酶的作用下释放出单核小孢子。红皮云杉单核小孢子经过3次不对称有丝分裂,形成4细胞的成熟花粉,包括2个原叶细胞,1个生殖细胞和1个管细胞。云杉属花粉的发育与松属基本相同,成熟花粉均由4个细胞组成。
The whole process of meiosis and pollen development of pollen mother cells (PMC) of Picea koraiensis was observed by tabletting method. It was confirmed that the meiosis of PMC in Picea koraiensis began each spring with a duration of 2 to 3 months. The meiotic metaphase divalent structure is dominated by a ring-shaped divalent body that exchanges at least twice with its two arms. Fewer rod-shaped bodies are observed. Mesenteric pachynema after the end of the obvious phase of the double-phase of dispersion. Cytokinesis occurs at the end of the second meiosis, belongs to the same type of split, the formation of tetrahedron is mainly tetrahedron. The tetrad configuration was also influenced by the second meiotic metaphase spindle orientation, in which the quadrilateral formed by the vertical arrangement of the spindle was a tetrahedron and the quadrilateral formed by the parallel arrangement of the spindle was quadrilateral. The tetrad releases small microspores under the action of the enzyme. The microspore of Picea koraiensis was asymmetrically mitotic after three times to form 4-cell mature pollen, including 2 cells of primordium, 1 germ cell and 1 tube cell. Picea pollen development and Pinus basically the same, the mature pollen by 4 cells.