Study on tissue culture and plant regeneration of hypocotyl and cotyledon of cytoplasmic male sterile line in cabbage.

【Objective】 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.【Method】 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.【Result】 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.【Conclusion】 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.