玉兰亚属及其近缘种植物遗传多样性分析

为了探析玉兰亚属(Subgenus Yulania)亲缘关系及遗传多样性,掌握玉兰亚属更多分子身份信息,本研究采用SSR分子标记技术,以14种玉兰亚属及其9个近缘种植物为材料,利用毛细管电泳技术进行检测,根据结果对23份材料进行聚类分析,并构建了玉兰亚属及其近缘种的指纹图谱。18对引物共检测到251个多态位点,多态性比率达100%。PIC含量变化范围为0.7508~0.9482,平均0.8794。Nei’s基因多样性指数最大为0.4998,最小为0.0430,Shannon信息指数变化范围为0.1057~0.6929,平均值0.2135。结果表明,供试材料具有较丰富的遗传多样性,玉兰亚属、木兰亚属(Subgenus Magnolia)及含笑属(Michelia)3个类群明显分开,在遗传相似系数0.776处供试玉兰亚属材料可分为4个组:紫玉兰组(section Tulipastrum)、玉兰组(sect.Yulania)、望春玉兰组(sect.Buergeria)、朱砂玉兰组(sect.Soulangeana)。建议将新种红花玉兰(Magnolia wufengensis)归并到玉兰组,不建议将含笑属与玉兰亚属合并。天目木兰(Magnolia amoena)与黄山木兰(Magnolia cylindrica)亲缘关系较近,紫玉兰(Magnolia liliflora)与望春玉兰组亲缘关系较近,源自美洲的渐叶木兰品种‘黄鸟’玉兰(Magnolia acuminata’Yellow Bird’)与中国的各种玉兰亲缘关系较远。本研究分析了玉兰亚属及其近缘种的遗传多样性及亲缘关系,获得了指纹图谱,可为玉兰亚属种质资源的系统分类及种质鉴定提供依据。

The Genetic Diversity Analysis of Subgenus Yulania and Its Related Species

In order to analyze the genetic relationship and genetic diversity of the Subgenus Yulania and master more molecular identity information,SSR molecular markers and capillary electrophoresis were used to study 14 species of Subgenus Yulania and its 9 related species.Fingerprints of the Subgenus Yulania and its related species were gained according to the clustering analysis of 23 materials.251 polymorphic loci were detected by 18 pairs of primers,with a polymorphic ratio of 100%.The range of PIC content ranged from 0.7508 to 0.9482,with an average of 0.8794.The Nei’s gene diversity index was 0.4998,the smallest was 0.0430,and the Shannon information index varied from 0.1057 to 0.6929,with an average of 0.2135.The results showed the abundant genetic diversity in tested materials,and 3 groups of Subgenus Yulania,Subgenus Magnolia and Michelia were distinctly separated.There were 4 groups of Subgenus Yulania(section Tulipastrum,sect.Yulania,sect.Buergeria and sect.Soulangeana)where the the genetic similarity coefficient is 0.776.It is suggested that the new species Magnolia wufengensis should be included into sect.Yulania,and it is not recommended to merge the Michelia and genus Yulania.The relationship between Magnolia amoena and Magnolia cylindrica is close,and the genetic relationship between Magnolia liliflora and sect.Tulipastrum is close.The Magnolia acuminata‘Yellow Bird’originated from the Americas is far from being related to all kinds of Magnolia in China.The genetic diversity and genetic relationship between the Subgenus Yulania and its related species were studied,and their fingerprints was obtained.Thus the basis can be provided for the systematic classification and germplasm identification of the germplasm resources of Subgenus Yulania.