甘薯小孢子发生的超微结构观察

Ultrastructural observations of microsporogenesis in sweet potato

甘薯小孢子发生过程中，细胞质超微结构发生了显著的变化．其变化主要涉及小泡、内质网、质体和核糖体．小泡在减数分裂过程中尤为丰富，参与胼胝质壁的形成．内质网在小孢子母细胞中非常丰富，在减数分裂过程中转化为小泡，在小孢子时期转化为内质网小泡．质体在小孢子母细胞中比较丰富，但处于退化状态，到小孢子时期尤为丰富并集中分布在细胞核的周围．核糖体的密度在小孢子母细胞和小孢子中均较高，在减数分裂过程中降低．

Remarkable cytoplasmic ultrastructural changes take place during the microsporogenesis of Ipomeoabatatas Lam.These changes mainly involve in the vesicles,endoplasmic reticulum, plastids and ribosomes.There are a lot of vesicles in the microspore mother cell during meiosis.The vesicles participate in the forming of callose wall.There are abundant endoplasmic reticulum in the microscope mother cell.Endoplasmic reticulum converte the vesicles during meiosis and the vesicular ER during early microspore stage.There are a log of plastids in the microspore mother cell;They are degenerating.There are particulat plenty plastids in early microspore stage;They are distributed around the nucleus.The ribosomes population of the cytoplasm is plenty in the microspore mother cell and the early microspore,and reduce during meiosis.