| 摘要: |
| [目的]以北极星、阿尔刚金、皇后2000及国产紫花苜蓿4个苜蓿品种下胚轴为外植体,建立其稳定、高效的离体培养再生体系,为基因转化改良苜蓿性状奠定基础.[方法]研究了种子预处理方法、培养基、基因型以及蔗糖质量浓度对苜蓿下胚轴分化特性的影响.[结果]低温4 ℃预处理有利于提高苜蓿下胚轴愈伤组织的出愈率和绿苗分化率;其最佳诱导激素组合为"MS 1.0 mg/L 2,4-D 2.0 mg/L 6-BA 5.5 g/L琼脂 30 g/L蔗糖"和"MS 2.0 mg/L 2,4-D 2.0 mg/L 6-BA 5.5 g/L琼脂 30 g/L蔗糖";愈伤组织分化的最佳培养基为"MS 0.3 mg/L 6-BA 3.0 mg/L KT 0.1 mg/L NAA 5.5 g/L琼脂 50 g/L蔗糖";最佳蔗糖质量浓度为50 g/L;4个紫花苜蓿品种愈伤组织诱导率的差异不大,但分化特性有较大差异,分化率由高到低依次为北极星、阿尔刚金、皇后2000和国产紫花.[结论]不同的种子预处理方法对4种紫花苜蓿品种的分化率均有一定影响,3种处理中以4 ℃下浸泡2 h处理的分化率最高,与其他处理间的差异达显著水平(P<0.05).不同激素组合是影响紫花苜蓿下胚轴愈伤组织诱导率和分化率的主要原因,不同激素组合处理间的差异均达到显著水平(P<0.05),2,4-D与6-BA配合对紫花苜蓿下胚轴愈伤组织的诱导效果较好,分化培养基中高质量浓度的NAA,不利于愈伤组织的分化;不同基因型对分化率有显著影响(P<0.05),而不同蔗糖质量浓度对分化率的影响不显著(P>0.05).说明其对离体培养再生体系的影响作用与处理方法、培养基、基因型相比是次要的. |
| 关键词: 紫花苜蓿 下胚轴 愈伤组织 离体再生体系 |
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| 基金项目:陕西省13115重大科技专项(2007ZDK-G02) |
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| Establishment of the system of high frequency regeneration from hypocotyls of Alfalfa |
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| Abstract: |
| 【Objective】 The system of high frequency and stable regeneration was established from hypocotyls of four kinds of Alfalfa named North Pole Star,Algonquin,Empress 2000 and Alfalfa of China in order to improve some characters by transforming some genes.【Method】 The research studied the effects of pretreatments,mediums,genotypes and the quality concentration of sucrose on the characters of hypocotyls.【Result】 The results showed that low temperature pretreatment such as 4 ℃ could improve the rates of calluses inducement and differentiation frequency.The best induction mediums were ‘MS+1.0 mg/L 2,4-D+2.0 mg/L 6-BA+5.5 g/L Agar+30 g/L Sucrose'and‘MS+2.0 mg/L 2,4-D+2.0 mg/L 6-BA+5.5 g/L Agar+30 g/L Sucrose’.The best differentiation medium was‘MS+0.3 mg/L 6-BA+3.0 mg/L KT+0.1 mg/L NAA+5.5 g/L Agar+50 g/L Sucrose’.Furthermore,the quality concentration of sucrose at 50 g/L was the best.And the rates of callus inducement of the four kinds of the Alfalfa weren't different but for the differentiation frequency,from high to low was North Pole Star,Algonquin,Empress 2000 and Alfalfa of China.【Conclusion】 The different pretreatments had influences on the differentiation frequency of the four kinds of Alfalfa.The correlation analysis between the three different pretreatments showed that there existed a remarkably significant correlation between the pretreatment that the seeds of Alfalfa soaked in 4 ℃ for two hours and the other two,and the rate of differentiation frequency was higher than those of the other two (P<0.05).The different endocrine combination was the main factors between the rate of calluses inducement and differentiation frequency from hypocotyls of the Alfalfa,in which existed a remarkably significant correlation(P<0.05).2,4-D added with 6-BA could enhance the inducement and differentiation frequency of hypocotyls from the four kinds of Alfalfa. In the differentiation mediums,the high level of NAA was bad for differentiation.The correlation analysis between genotypes and the quality concentration of sucrose showed that there existed a remarkably significant correlation of genotypes（P<0.05）while no significant correlation existed of the quality concentration of sucrose according to differentiation frequency(P>0.05),which showed that the effects were lower than different pretreatments,mediums and genotypes. |
| Key words: Alfalfa hypocotyls callus regeneration system |
