磨盘柿败育杂种胚胎发育的细胞学特征

为揭示磨盘柿杂种败育的细胞学机制,采用常规石蜡切片法观察了磨盘柿正常杂种及早期和晚期败育型杂种的胚胎发育过程。结果表明,正常杂种的胚在授粉后35、40、45、55d依次发育至球形期、心形期、鱼雷期和子叶期;与正常杂种相比,早期败育型杂种的初生胚乳核分裂出现异常,多数胚最终只能发育至球形早期;晚期败育型杂种的胚乳没有明显的异常现象,但胚发育滞后,且着生位置偏离珠孔,呈横生或斜生状态;2种败育杂种在种形异常之前胚基本正常,可望借助胚挽救手段分别于授粉后30～40d及60～70d进行离体培养获得F1杂种。

Cytological research on abnormal hybrid seeds in parthenocarpic Mopanshi persimmon cultivar

Development of embryo and endosperm in normal and abnormal hybrid seeds was histologically investigated to clarify the cause of seed abortion in Chinese parthenocarpic persimmon Mopanshi when Nishimurawase persimmon cultivar was used as pollinator. The observation of embryogenesis showed that the embryos in normal seeds always developed to globular embryo, heart-shaped embryo, torpedo-shaped embryo and cotyledonary embryo stage in 35, 40, 45 and 55 d after pollination, respectively. The majority embryo of seeds aborted at earlier stage could develop to earlier globular embryo phase due to the abnormal endosperm nucleus division. Although endosperm abnormality was not distinguishable from perfect ones, embryo development delay occurred in seeds with protuberance. With a view to the embryos were zoetic and available before their abnormal appearance in shape, F1 hybrids could be expected for seeds aborting in earlier or later stage by embryo rescue conducted in 30 to 40 d or 60 to 70 d after pollination, respectively.