秋石斛新生侧芽中部茎段组培快繁体系的建立

Establishment of tissue culture and rapid propagation system for middle stem of Dendrobium hybrida young lateral bud

【目的】建立秋石斛新生侧芽中部茎段组培快繁体系,为秋石斛的快速繁殖及其杂交育种后代优良单株扩繁提供技术支持。【方法】以秋石斛红牛新生侧芽中部茎段为外植体,分别接种于固体和半固体培养基,进行不同激素组合处理,探讨固体培养基和半固体培养基及不同激素处理对秋石斛新生侧芽中部茎段的组培效果。【结果】在芽的诱导中,诱导率随6-BA浓度增加呈先升后降趋势,当6-BA为3.0 mg/L、NAA浓度为0.1 mg/L时诱导效果最佳,其成活率、诱导出芽率分别为91.11%和85.19%。在芽增殖培养中,增殖效率随6-BA浓度增加呈先升后降趋势,当6-BA浓度为2.0 mg/L时增殖效率最高,增殖倍数达4.75倍。在生根壮苗中,NAA的生根壮苗效果比IBA好,以0.7mg/L NAA生根壮苗效果最佳,生根率、根系数量及平均根系长度、株高、茎粗分别为97.32%、12.17条和3.50、4.18、0.41 cm。【结论】半固体培养基比固体培养基更适合秋石斛新生侧芽中部茎段组培快繁。秋石斛新生侧芽中部茎段在芽诱导培养基MS+6-BA 3.0 mg/L+NAA 0.1 mg/L、芽增殖培养基MS+6-BA 2.0 mg/L+NAA 0.1 mg/L、生根壮苗培养基1/2MS+NAA 0.7 mg/L中进行组培快繁效果最佳。

【Objective】The present experiment was conducted to establish rapid propagation technique system of middle stem from Dendrobium hybrida young lateral bud, in order to provide technical support for its rapid propagation and propagating improved individual plant through crossbreeding. 【Method】The middle stem of D. hybrida Red Bull young lateral bud was used as explant, which was incubated on solid and semi-solid mediums with different combination of hormones, respectively. Then the solid and semi-solid mediums and different hormone treatments on tissue culture of middle stem from Dendrobium hybrida young lateral bud were investigated, and the effects on survival rate, bud induction, budproliferation, rooting and growth of plantlet were analysed. 【Result】The results showed that, as for bud induction, the induction rate first increased and then decreased with the increase of 6-BA concentration, and when 6-BA concentration was 3.0 mg/L and NAA concentration was 0.1 mg/L, the best induction result was obtained, the survival rate and budding rate were 91.11% and 85.19%, respectively. As for bud proliferation, the proliferation efficiency first increased and then decreased with the increase of 6-BA concentration, and when 6-BA concentration was 2.0 mg/L, the best proliferation result was obtained, and the proliferative multiple reached up to 4.75. As for promoting rootage and growth of plantlet, NAA showed better rooting and growth-promoting effects than IBA, and the best effect was obtained when NAA concentration was 0.7 mg/L, the rooting rate, root number, average root length, plant height and stem diameter was 97.32%, 12.17,3.50 cm, 4.18 cm and 0.41 cm, respectively. 【Conclusion】The semi-solid medium is more suitable for tissue culture rapid propagation of middle stem from D. hybrida young lateral bud than solid medium. Furthermore, the optimal rapid propagation effect was obtained by using MS＋3.0 mg/L 6-BA＋0.1 mg/L NAA as medium for inducting buds, MS＋2.0 mg/L 6-BA＋0.1 mg/L NAA as medium for proliferating buds, 1/2MS ＋NAA 0.70 mg/L NAA as medium for promoting rootage and growth of plantlets.