基于SSR标记构建叶子花品种的分子身份证

Construction of molecular ID of Bougainvillea varieties based on SSR markers

以219个叶子花栽培品种为研究对象,在140对引物中筛选出20对多态性高的简单重复序列(SSR)荧光标记引物对219个品种进行扩增,共扩增出414条带型,平均每对引物扩增出20.7条;20对引物的多态性信息含量(PIC)为0.189~0.823,平均值为0.696,当PIC>0.50时可以认为该引物为高度多态性信息引物;20对引物在219个品种中共检测出219个等位基因,平均每对引物检测出10.95个;20对引物在219个品种组成的群体中,其平均有效等位基因数为4.212个,平均Shannon多样性指数为1.633,平均观测杂合度为0.430。在构建叶子花品种分子身份证方面,通过SSR标记技术,根据PIC的高低选择引物组合,采用数字与英文大小写字母相结合的方法,对不同长度的扩增片段进行赋值,最终用20对引物构建了219个叶子花品种的分子身份证,并通过在线软件进一步转换成唯一可识别的品种信息二维码。叶子花品种分子身份证和信息二维码的构建,可避免出现由于品种繁多及命名混乱而导致的同名异物和同物异名的现象,促进品种知识产权保护,做到种质可追溯。

219 cultivated varieties of Bougainvillea were amplified using 20 pairs of highly polymorphistic simple sequence repeats(SSR)primer which were screened from 219 primer pairs.A total of 414 bands were amplified,with an average of 20.7 bands per primer pair.The polymorphism information content(PIC)value of the 20 primer pairs was 0.189-0.823 and averaged at 0.696,and the primer pair with PIC value greater than 0.5 can be considered highly polymorphic.With the 20 primer pairs,up to 219 alleles were detected from the 219 cultivated varieties with an average of 10.95 alleles per primer pair,and these cultivated varieties showed average number of effective alleles,Shannon diversity index,and observed heterozygosity of 4.212,1.633 and 0.430,respectively.Through SSR marker technology,primer combinations were selected successively according to PIC values,and then the selected 20 primer pairs were used to distinguish the cultivated varieties.Lastly,their amplified fragments with different lengths were annotated by the combination of numbers and uppercase and lowercase letters.Based on these information,each Bougainvillea variety was en⁃dowed with a unique molecular ID which can be further converted into a 2⁃dimensional code through online software.The construc⁃tion of molecular ID avoided the naming confusion of Bougainvillea variety and achieved germplasm traceability,thus promoting vari⁃ety breeding and protection.