Study on tissue culture and plant regeneration of hypocotyl and cotyledon of cytoplasmic male sterile line in cabbage | 甘蓝CMS下胚轴和子叶的离体培养与植株再生研究

Chinese. 探索一种利用甘蓝胞质雄性不育系（CMS）下胚轴和子叶进行快速扩繁的技术，为利用CMS大量繁制甘蓝杂交种提供一条新途径。以甘蓝CMS 05-2-10为试材，将苗龄5～7 d无菌苗的下胚轴和子叶切下，接种于MS培养基上，45~50 d后统计再生芽数，比较6-BA与NAA不同质量浓度配比对不定芽的诱导情况；将诱导出的不定芽接种于添加不同质量浓度（0，0.1，0.3，0.5 mg/L）NAA的MS生根培养基上，20 d后比较生根率和根的长势。在对下胚轴和子叶进行不定芽诱导时，MS培养基中分别添加1.0和4.0 mg/L的6-BA对下胚轴、子叶的诱导效果较好，其芽再生频率和分化系数分别为83.3%，53.0%和3.6，3.0。在MS培养基中添加1.0 mg/L 6-BA+0.2 mg/L NAA，其对下胚轴不定芽的诱导效果较好，芽再生频率为80.7%，分化系数为3.4，褐化率为1.5%；在MS培养基中添加4.0 mg/L 6-BA+0.3 mg/L NAA，其对子叶不定芽的诱导效果较好，芽再生频率为50.0%,分化系数为3.2，褐化率为3.4%；二者的褐化率均明显低于仅添加6-BA的处理。在MS生根培养基中添加0.3 mg/L NAA时，不定芽的生根效果较好，生根率达100%，且根系生长健壮。利用甘蓝胞质雄性不育系CMS 05-2-10的下胚轴和子叶作为外植体进行不定芽的诱导，对于下胚轴，其适宜培养基为MS+1.0 mg/L 6-BA+30 g/L蔗糖+8 g/L 琼脂；对于子叶，其适宜培养基为MS+4.0 mg/L 6-BA+30 g/L 蔗糖+8 g/L 琼脂。不定芽诱导生根的最适培养基为MS+0.3 mg/L NAA+30 g/L蔗糖 + 8 g/L 琼脂。

English. This experimentation aimed to explore fast propagation technology using hypocotyl and cotyledon of cytoplasmic male sterile line in cabbage to offer a way to produce hybrid cabbage by using cytoplasmic male sterile line. Cytoplasmic male sterile CMS 05-2-10 of cabbage was studied. Hypocotyl and cotyledon taken from 5－7 d seedling were inoculated in MS medium. The number of adventitious buds after 45－50 days was counted, and the result of hormone combinations of 6-BA and NAA on adventitious buds of induction was compared; adventitious buds were inoculated on MS medium supplement with different concentrations（0, 0.1, 0.3, 0.5 mg/L）of NAA. The condition of rooting rate and growth vigour of root was analyzed. When adventitious bud of hypocotyl and cotyledon were induced, the effects of adding 1.0 and 4.0 mg/L 6-BA in MS medium on adventitious bud regeneration were better, shoot regeneration frequency and coefficient of differentiation were 83.3%, 53.0% and 3.6, 3.0 respectively. The effect of adding 1.0 mg/L 6-BA+0.2 mg/L NAA in MS medium on adventitious bud regeneration of hypocotyl was better, shoot regeneration frequency was 80.7%, coefficient of differentiation 3.4, browning rate 1.5%; The effect of adding 4.0 mg/L 6-BA+0.3 mg/L NAA in MS medium on adventitious bud regeneration of cotyledon was better, shoot regeneration frequency was 50.0%, coefficient of differentiation 3.2, browning rate 3.4%. Both of them can significantly reduce browning rate in comparison with only adding 6-BA. The effect of adding 0.3 mg/L NAA in MS medium on rooting culture was better, rooting rate of adventitious bud reached 100%, and the root can grow strongly. Taking the hypocotyl and cotyledon of cytoplasmic male sterile CMS 05-2-10 of cabbage as explants to induce adventitious bud, the suitable medium on adventitious bud regeneration of hypocotyl is MS+1.0 mg/L 6-BA+30 g/L sucrose+8 g/L agar; the suitable medium on adventitious bud regeneration of cotyledon is MS+4.0 mg/L 6-BA+30 g/L sucrose+8 g/L agar. The suitable medium for root induction is MS+0.3 mg/L NAA+30 g/L sucrose+8 g/L agar.