一个高频率的活体-离体胚胎发生研究系统

通过对受精后烟草(Nicotiana tabacumL.)胚珠的体外培养,建立了一个简便、实用、高频率的胚胎发生研究系统。采用MS培养基附加6%蔗糖,然后换以2%蔗糖对烟草胚珠进行培养,结果受精后胚珠在体外可以完成正常的胚胎发生并可直接萌发成幼苗。追踪观察表明,合子体外胚胎发生过程中关键发育事件,如合子休眠期间的定向生长、一次不对称分裂的完成、胚柄的形成和解体、胚的分化等过程均可在体外重现。体外培养形成的胚珠及胚胎在形态上与自然状态下形成的胚珠及胚胎几乎没有差异。此体系操作简单,稳定性好,且关键发育事件的时空调控与自然胚胎发育进程相吻合。

A High-frequency in vivo-in vitro Experimental System for Embryogenesis Study

An in vivo-in vitro experimental system was set up,in which zygotes could develop into fertile plants through normal embryogenesis with high frequency by means of ovule culture.Some key developmental events of embryogenesis,such as directional expansion,asymmetrical first division,suspensor formation and degeneration as well as embryo differentiation,occurred as that in in planta embryogenesis in the experimental condition.No morphological difference was observed between embryos gained from ovule culture and embryos grown in planta,indicating that the in vitro ovule culture system phenocopies the in planta developmental program of embryogenesis.This system is simple and stable,and therefore can be a useful tool for the study of embryogenesis mechanism.