水稻“双－3”多胚发生的研究

POLYEMBRYOGENESIS IN APOMIXISPARENT Ⅳ OF RICE

水稻ＭＩＶ（双－３、籼稻）传粉后可以有多个花粉管同时进入胚囊．大多数胚囊的合子发育为一个正常的胚，但是有少数合子胚发生裂生并分化形成双胚芽和一胚根．有些胚囊的助细胞和卵细胞同时受精后，分别发育为助细胞胚和合子胚；有些胚囊中的反足细胞团可直接发育为胚．可见“双－３”水稻除有正常合子胚外还存在助细胞胚和反足细胞匹的多胚现象．

More than one pollen tube entering into one embryo sac was observed after pollinationin Apomixis parent Ⅳ,an indica rice twin seedling line.Zygotes of most embryo sacsdeveloped into normal zygotic embryos,but a few Zygotes developed into cleaved Zygoticembryos through apical cleaving of proembryos and formed seedlings, each of whichwith two plumules and one radicle.In some embryo sacs,synergid cells developed intosynergid embryos after fertilization.In some embryo sacs, without fertilization,antipodalcells directly developed into antipodal embryos.