苜蓿不同品种愈伤组织诱导、分化和再生能力的比较研究

以新疆大叶、甘农1号、甘农3号和陇东4个苜蓿品种的下胚轴、子叶和子叶节为外植体,比较了不同苜蓿品种及外植体愈伤组织诱导、分化及再生能力的差异,研究了不同浓度及配比的植物生长调节物质对愈伤组织诱导和芽分化再生的影响。结果表明,4个苜蓿品种再生能力依次为新疆大叶>甘农3号>甘农1号>陇东苜蓿,下胚轴外植体在愈伤诱导培养基(MS 2mg/L2,4-D 0.2mg/LZT)上出愈率分别为94%,83%,71%和58%,胚性愈伤组织在分化培养基(MS 0.2mg/LZT 50mg/L谷氨酰胺)上分化率分别为15.8%,9.2%,7.1%和4.5%;下胚轴再生能力优于子叶节和子叶;丛生芽在生根培养基(1/2MS)上生成完整的根;各品种的再生苜蓿植株均成功移栽到土壤中,成活率100%。上述4个苜蓿品种分化再生能力的阶段性研究结果为今后通过基因工程方法改良苜蓿奠定了基础。

Comparative Study on Callus Induction, Differentiation and Regeneration Capacity of Different Alfalfa (Medicago sativa L.)Cultivars

In this paper, a comparison is made on callus induction, differentiation and regeneration capacity of cotyledons, cotyledonary nodes and hypocotyls of four alfalfa cultivars: XinjiangDaye, Longdong, Gannong No. 1 and Gannong No. 3. The effects of different combinations and concentrations of plant growth regulators on callus induction and shoot differentiation are studied. The results show that the regeneration capacity of different cultivars is in the following order: XinjiangDaye>Gannong No. 3>Gannong No. 1>Longdong, with hypocotyls being better than cotyledons and cotyledonary nodes. Callus formation frequencies of hypocotyls on MS 2mg/L 2, 4-D 0.2mg/L ZT are, respectively, 94%, 83%, 71% and 58%. Shoot differentiation frequencies on MS 0.2mg/L ZT 50mg/L Glutamine are, respectively, 15.8%, 9.2%, 7.1% and 4.5%. The regenerating shoots would develop rooting systems, which grow well on 1/2 MS media. All regenerated alfalfa plantlets were successfully transferred into the soil. This study on alfalfa regenerated capacity provides a foundation for further alfalfa improvement through genetic engineering strategies.