紫花苜蓿体细胞胚高频再生体系的建立

以我国农艺性状优良的丰产紫花苜蓿Medicago sativa品种大叶苜蓿和甘肃省广为种植的优质紫花苜蓿品种陇东、陇中、甘农1号、甘农3号等的下胚轴、子叶、叶片和叶柄为外植体研究了不同培养基、激素配比以及脯氨酸、蔗糖和活性炭对紫花苜蓿胚性愈伤组织和体细胞胚诱导分化的影响,结果表明:最佳胚性愈伤诱导培养基为MS 2,4-D 5 mg/L KT 1 mg/L;最佳外植体为下胚轴。最佳体细胞胚诱导和分化培养基为SH;脯氨酸对体细胞胚的诱导分化无明显作用;在培养基中添加活性炭会降低体细胞胚诱导率;蔗糖浓度为20 g/L时体细胞胚诱导率最高。同时还建立了紫花苜蓿体细胞胚高频再生体系,为根癌农杆菌介导AtNHX1基因对紫花苜蓿的遗传转化打下了坚实的基础。

The establishment of high frequency regeneration system of alfalfa somatic embryos

The hypocotyl,cotyledon,petiole and leaf of five Chinese local alfalfa cultivars were used to study the effect of different basic mediums,different hormone combinations,different proline,sucrose concentrations and active carbon on embryogenic callus and somatic embryos induction and differentiation.The results indicated that MS containing 5.0 mg/L 2,4-D and 1.0 mg/L KT(MSH) was the optimum embryonic callus induction medium.Hypocotyl was the best explant for rapid callus induction.The hypocotyl callus induction rate of Longdong and Daye was close to 100% on MSH.SH medium was the most efficient for inducing somatic embryos,on which,the somatic embryos induction rate of Longdong and Daye was up to 72% and 58% respectively.1/2MS with 10 g/L sucrose was propitious for rooting and seedling of somatic embryos.Proline had no effect on induction and differentiation of somatic embryos,adding active carbon in SH medium can reduce somatic embryos induction rates,the highest somatic embryos induction rate for sucrose was 20 g/L.The establishment of high frequency regeneration system of alfalfa somatic embryos benefits the AtNHX1 gene transformation of alfalfa greatly.