二穗短柄草植株再生体系的建立

Establishment of plantlet regeneration system using mature seeds of Brachypodium distachyum

以成熟种子为外植体建立二穗短柄草植株再生体系,结果表明:二穗短柄草成熟种子经1%次氯酸钠消毒液处理20min,接种于MS+4%蔗糖(pH 5.5)培养基中培养5d,萌发率为90%,褐化率为10%,污染率为0;萌发种子转入到愈伤组织诱导培养基MS+1mg/L 6-BA+1mg/L 2,4-D+0.5mg/L NAA+4%蔗糖(pH 5.5)上继代培养,光照条件下愈伤组织诱导率为86%,黑暗条件下愈伤组织诱导率为64%;二穗短柄草愈伤组织在MS+2mg/L 6-BA+0.1mg/L 2,4-D+0.5mg/L NAA+4%蔗糖(pH 5.5)进行不定芽诱导,不定芽发生率为90%;无根丛生芽继代转入到不定根诱导培养基1/2MS+0.5mg/L IBA+0.25mg/L NAA+4%蔗糖(pH 5.5)中,5d以后可以见到不定根的形成,15d后不定根发生率为91%;在研究中还发现,二穗短柄草种子萌发后可直接继代转入不定芽分化培养基形成健壮不定芽,不定芽诱导率为94%。

The plantlet regeneration system was established using mature seeds of Brachypodium distachyumas explants.When the seeds were treated with 1%thimerosal（sodium hypochlorite）for 20 minutes and inoculated into MS＋4% sucrose（pH5.5）medium,90% of the seed germination rate and 10% of the browning rate were obtained after 5days culture.The germinated seeds were subcultured to the calli inducing medium MS＋1mg/L 6-BA＋1mg/L 2,4-D＋0.5mg/L NAA＋4% sucrose（pH 5.5）.The calli formation rate was more than 86% under illumination conditions and 64% under dark conditions.The adventitious buds differentiation rate was 90% with the adventitious buds inducing medium MS＋2mg/L6-BA＋0.1mg/L 2,4-D＋0.5mg/L NAA＋4% sucrose（pH 5.5）.The adventitious roots were formed 5days after introduction in the adventitious roots inducing medium 1/2MS＋0.5mg/L IBA＋0.25mg/L NAA＋4% sucrose（pH 5.5）,with the adventitious root differentition rate reaching 91% after 15 days culture.The adventitious buds were also induced after the germinated seeds were subcultured directly to the adventitious buds differentiation medium,with 94%inducing rate of adventitious buds.