优质速生抗虫紫花苜蓿多元杂交后代的ISSR分析

ISSR Analysis of Hybrid Progeny of Good Quality,Fast-growing and Insect-resistant Medicago Multiple Parents Cross

应用ISSR分子标记技术研究苜蓿品种甘农3号、甘农5号、游客及其杂交后代19份材料的遗传多样性,为其遗传改良和分子标记辅助育种提供依据。结果:6个ISSR引物共扩增出37条带,其中31条带是多态性谱带,多态性比率平均值为83.78%,平均每个引物扩增出6.17条带。用POPEGENE 32软件分析有效等位基数(Ne)、Nei’s基因多样性指数(H)、Shannon’s信息指数(I)的平均值分别为1.484 2、0.287 5、0.432 3,遗传多样性水平较高;19份材料间的遗传相似系数(GS)为0. 486 5～0.945 9;通过UPGMA分子系统聚类法构建分子树状图,可把19份材料划分为5个类群,第1类包括速生1~#、速生11~#、速生12~#共3份种质材料;第2类包括速生5~#、大叶2~#、速生26~#、直立、甘农5号、速生15~#、速生17~#、速生20~#、速生19~#共9份种质材料;第3类包括速生4~#、白花1~#、白花2~#、白花3~#、甘农3号共5份种质材料;速生2~#、游客分别单独聚为一类。

Inter-simple sequence repeat （ISSR）techniques were used to identify the genetic diversity of 19 Medicago germplasms collected from Gannong No.3, Gannong No.5, Tourists and their 16 hybrid progenies. This study provided scientific basic for genetic improvement and molecular marker -assisted breeding of Medicagn. Results showed that a total of 37 bands were amplified by 6 ISSR primers, in which 31 bands were polymorphic. The average percentage of polymorphic bands was 83.78%, each primer amplified 6.17 DNA bands on average. Mean values of Effective number of alleles, Nei＇ s gene diversity index （H） and the Shannon diversity index （I） were 1.484 2, 0.287 5 and 0.432 3 by POPEGENE 32 software analysis. The genetic similarity （GS） among 19 germplasms was 0.486 5-0.945 9. The 19 Medicagn germplasms were classified into 5 major groups based on UPGMA cluster analysis. This first group included fast-growing 1# , fast-growing 11#and fast-growing 12#. The second group included fast-growing 5# , big leaf 2# , fast -growing 26# , erect type, fast-growing 15# , fast-growing 17# , fast-growing 20# , fast-growing 19# , Gannong No.5. The third group included fast-growing 4# , white flower 1# , white flower 2# , white flower 3# , Gannong No.3, the forth group and fifth group included eruka and fast-growing 2# respectively.