吉林省玉米新品种SSR标记指纹数据库的构建及其分析

Construction and Analysis of the SSR-based Fingerprinting Database for New Maize Varieties in Jilin Province

以SSR标记为技术手段,利用20对核心引物,构建吉林省2005～2009年审定的174份普通玉米新品种的DNA指纹数据库,同时分析不同年份间审定品种的等位基因频率、等位基因数目、多态性信息指数的变化。结果表明,2005～2009年供试174份材料的平均等位基因数目略有下降,但平均多态性信息指数没有明显变化,不同年份间玉米品种的个别等位基因频率变化比较明显,分析可能在育种过程中人为施加了较强的定向选择而保留了下来,说明随着年份的变化,个别稀有等位基因可能在减少,但遗传多样性并没有降低。同时说明在评价玉米品种遗传多样性变化时,多态性信息指数反映的应该更加客观一些。吉林省玉米品种不同年度间的遗传多样性无明显变化,说明近些年吉林省审定的品种在育种资源、育种模式以及育种方向上变化较小,没有较大的突破。

A DNA fingerprinting database containing 174 new maize varieties authorized by Jilin Province from 2005 to 2009 was constructed using 20 SSR loci.The genetic difference among different years was analyzed based on the number and frequency of alleles and polymorphism information content（PIC）.Through the analysis,we can see that the average number of alleles of 174 new maize varieties from 2005 to 2009 was a fell slightly trend,but there is not apparent change in the average index of polymorphism information.The change of individual allele frequency is apparent in corn varieties of different years.According to the analysis,the remains maybe because of the strong directional selection putting in breeding process analysis.That means as the change of the year,the individual rare alleles may be decreased,but the genetic diversity is no lower.This also shows the reflection of polymorphism information index should be more objective when we evaluate the change of corn genetic diversity.Overall,there is no apparent change in genetic diversity among Jilin corn varieties of different years,which means the corn varieties authorized by Jilin province in recent years have no large fluctuations in breeding resources,breeding mode,and the breeding direction.