Studies on plantlet formation of microspore embryoid in spring Brassica napus L.

【Objective】Factors affecting the plantlet of embryoid were studied in order to enhance plantlet rate of embroids.【Method】Using 5964 embryoids obtained from microspore culture as material,the paper analyzed differences in the rate of seeding,which were caused by embryoid length,humidity in flask,agar concentration in B5 medium and low-temperature processing time.【Result】The way of placement in the solid medium affected embryoids morphological development.The seedling rate of 3-4mm embryoid was the highest,reaching 61.3%.The seedling rate of the third-pecking method was the highest,reaching 65.2%.With the increase of agar ccncentration embryoid seedling rate increased first and then decreased.The medium with 12g/L agar presented the highest seedling rate 61.3%.4℃ low temperature treatment for 14 days obtained a seedling rate of 65.5%.【Conclusion】Hypoxia and low temperature treatment affected morphogenesis development of embryoid.Plantlet was related to the degree of embryoid development,humidity in flask,agar concentration and low-temperature treatment time.B5+1.2% agar was a suitable medium.Low temperature treatment at 4℃ for 14 days was the best.