长期离体培养的春石斛兰类原球茎生长及生根条件的优化

为解决春石斛兰(Dendrobium nobile)类原球茎(protocorm-like body,简称PLB)长时期离体培养后生长缓慢、形成的嫩梢瘦小及根系难于发生等问题,本文从生长调节剂、有机添加物、蔗糖和嫩梢高度等因子,对PLB的增殖、生长与生根等方面进行了系统研究。结果表明:0.5mg/L BA最适合PLB增殖和生长;20g/L的蔗糖最适合嫩梢的生根;IBA虽在一定程度上促进生根,但嫩梢高度才是决定生根的关键,2.5cm的嫩稍在添加0.05mg/L的IBA的培养基上,生根率提高到51.11%;鲜重增长倍数与PLB增殖倍数的比值(F/P值)是衡量PLB正常生长与否的一个重要指标,F/P≥0.6时,PLB生长健壮。

OPTIMIZATION OF CULTURE CONDITIONS FOR GROWTH AND ROOTING OF PROTOCORM-LIKE BODIES OF Dendrobium nobile in vitro

To solve the problems of weak growth and low rooting potential of long period subcultured Dendrobium nobile protocorm-like bodies(PLBs) in vitro,the effects of organic additives,plant growth regulators,sucrose and heights of the shoots on the growth,proliferation and rooting of the PLBs were systematically studied.The results indicate that 0.5 mg/L BA was suitable for the growth and proliferation of the PLBs,and 20 g/L sucrose suitable for rooting.Although IBA stimulated rooting of the shoots,the height of shoot was crucial.On the basal medium supplemented with 0.05 mg/L IBA,the rooting percentage of the 2.5 cm high shoots reached 51.11%.F/P rate(increasing rate of fresh weight of PLBs/increasing rate of proliferation of PLBs) is a key parameter to distinguish whether the growth of the PLBs is normal or not.When F/P≥0.6,the PLBs grew well.