Abstract: The regenerative systems of Medicago satvia L.(cv.Peru,Guanzhong,and Gannong No.3) and Medicago varia Martyn(cv.Gannong No.1 and Gannong No.2)were comparatively studied by this paper.The results show that the regenerative ability was evidently different between M.satvia and M.varia with the former was remarkably higher than the latter.The cotyledon was the optimal explant material and the 2,4-D level had the less effect no the callus induction of M.sativa,but that of M.varia was evidently enhanced with the increased concentration of 2,4-D.The effective medium for inducing callus of M.satvia was MS supplemented with 2.0 mg/L 2,4-D and 30 g/L sucrose,and the inducing rate was above 95%.M.varia had higher callus inducing rate on medium MS supplemented with 4.0 mg/L 2,4-D and 30 g/L sucrose,and the inducing rate was 65.6% and 73.3%.The optimal differentiation medium of these 5 cultivars was MS containing 1.0 mg/L KT,0.5 mg/L NAA,and 20 g/L sucrose but the differentiation rate of the cultivars of M.satvia was about 70% and that of M.varia was 30%.The effective root inducing medium was 1/2 MS supplemented with 1.0 mg/L IBA.This research established a high regenerative system for M.satvia which could be the base for genetic transformation;at same time,it also provided the basic information to the establishment of effective regeneration system for M.varia.

Key words: Medicago sativa L., Medicago varia Martyn, Regeneration system

摘要： 对紫花苜蓿(Medicago sativa L.)(秘鲁、关中、甘农3号)及杂花苜蓿(Medicagovaria Martyn)(甘农1号、甘农2号)组培再生体系各影响因子进行比较研究。结果表明:紫花、杂花苜蓿的组培再生能力差异较大,前者显著高于后者;在愈伤组织诱导中,子叶节是最佳的外植体材料;2,4-D浓度增加对紫花苜蓿出愈率影响不明显,但杂花苜蓿的出愈率随着2,4-D浓度的增加呈明显的升高趋势;紫花苜蓿的最佳愈伤组织诱导培养基为MS₊2,4-D2.0mg/L+蔗糖30g/L,诱导率均在95%以上;杂花苜蓿为MS₊2,4-D 4.0mg/L+蔗糖30 g/L,两个品种诱导率分别为65.6%、73.3%;5个品种的最适分化培养基均为MS₊KT 1.0 mg/L+NAA 0.5mg/L+蔗糖20 g/L或MS₊BA4.0 mg/L,分化率也各有差异,紫花苜蓿不定芽的分化率可达到70%左右,而杂花苜蓿在30%左右;最佳诱导生根的培养基为1/2MS₊IBA 1.0 mg/L;本研究建立了紫花苜蓿高频再生组织培养体系,为实现外源基因的高效遗传转化奠定基础;通过紫花苜蓿和杂花苜蓿的再生体系影响因子的比较研究,为杂花苜蓿再生体系的建立提供参考。

关键词: 紫花苜蓿, 杂花苜蓿, 再生体系