荔枝胚性悬浮细胞系的快速建立及其体胚植株的再生

荔枝幼胚诱导的胚性培养物在低糖条件下连续继代4~6次左右，可筛选到颗粒细小、不含原胚的松散型胚性愈伤组织；以这种松散的胚性愈伤组织作为起始材料，在附加2,4-D 2mg/L或2,4-D 2mg/L、KT1 mg/L、AgNO3 5mg/L的MS液体启动培养基上振荡培养（100~120 r/min）10~14 d，即可建立起分散性良好的胚性悬浮细胞系。采用激素减半的2种启动培养基交替继代培养或周期性固体－液体轮回培养，可以长期保持胚性悬浮细胞系。荔枝胚性悬浮细胞在附加NAA 0.1 mg/L、KT 或Ze 5 mg/L、肌醇100 mg/L、蔗糖50g/L、琼脂10g/L的MS固体培养基上诱导体胚，25~40d后可形成大量胚状体，诱导体胚数量达10,000个/g FW以上。经过成熟培养后，正常的体胚75%以上萌发再生完整植株。

Rapid Establishment of Embryogenic Cell Suspensions and Plant Regeneration via Somatic Embryogenesis in Litchi

The friable embryogenic callus with small grains and without proembryo formation was screened in the process of continuous subcultures for 4~6 times on the medium with low content of sucrose from embryogenic cultures induced from immature embryos in litchi (Litchi chinensis Soon.). The well-scattered embryogenic cell suspensions could be rapidly established from the friable embryogenic callus in 2 liquid initial MS media respectively supplemented with 2,4-D 2 mg/L or 2,4-D 2 mg/L, KT1 mg/L and AgNO3 5 mg/L shaking at 100~120 r/min within 10-14 days. Long-term maintenance of the embryogenic cell suspensions was achieved via alternative cultures in the 2 revised initial medium only with half-strength of phytohormones or through the method of periodical in-turn liquid-solid culture. The embryogenic suspension cells formed somatic embryos at the frequency of over 10,000 embryoids/g FW on the solid MS medium amended with NAA 0.1 mg/L, KT or Ze 5 mg/L, sucrose 50 g/L, agar 10g/L and myo-inositol 100 mg/L within 25~40 days. Normal somatic embryos were converted into plantlets by over 75% after maturation.