摘要
小麦族含有St、H、Y基因组的物种是禾本科小麦族最大的一个类群,它们不仅包含许多优良的牧草资源,还含有许多优异的抗逆基因资源,是牧草和麦类作物育种重要的基因库,具有重要的经济和生态价值。然而该类群物种的种属界限及系统关系一直存在争议,特别是六倍体物种间的亲缘关系争议较大,相关的研究还较少,其限制了该类群物种种质资源的进一步开发利用。研究小麦族St、H、Y基因组六倍体物种种间亲缘关系可为该类群物种的遗传多样性、种属关系及系统演化关系等提供重要参考。系统收集具有StHY、StStY、StStH、StHH基因组组成的六倍体物种25个,选用具有高通用性的SSR分子标记对其种间遗传变异、分化及亲缘关系进行分析。研究结果表明:1)27对SSR引物在46份供试材料中扩增出条带共229条,其中多态性条带213条,比率为93.01%;2)Dice遗传相似系数表明供试材料间的系数变异为0.479~0.981,平均值为0.670;StHY、StStY、StStH和StHH不同基因组组成物种内的相似系数变化分别为0.544~0.981、0.509~0.899、0.530~0.843和0.550~0.827,平均值分别为0.722、0.700、0.663、0.677;其揭示了供试物种之间存在丰富的遗传变异和不同程度的种间分化;3)聚类分析结果表明,不同基因组组成的物种间亲缘关系相对较远,相同基因组组成物种基本上能聚在一起且表现出不同程度的分化类型,其中StHY物种间分化最为显著,并与其形态特征表现出一定的一致性;4)进一步明确了国产的披碱草属六倍体物种均为StHY基因组组成。研究结果揭示了供试的不同基因组组成的六倍体物种之间具有丰富的遗传多样性和明显的种间分化,其中StHY物种可明显分化成3种类型;相同或相似基因组组成的物种间表现出了较近的亲缘关系,研究结果支持基于基因组组成的分类体系对该类群物种分类地位的划分。
Species with St,H and Y genomes comprise the largest group in the tribe Triticeae,which includes many important forage grasses and is the source of elite genes for improving forage and cereal crops.While this group has considerable economic and ecological value,the nature of its inter genera and interspecific relationships remains a matter a dispute,especially for hexaploid species.Relatively little research has been undertaken on interspecific relationships among these species,which has limited the ability to utilize their germplasm resources.Therefore,this study aimed to reveal the interspecific affinity of the group’s hexaploid species and so to provide important information on their genetic diversity and biosystematics.A total of25hexaploid species with StHY,StStY,StStH and StHH genomic constitutions were systematically collected and highly transferable SSR markers were used to study their genetic variation,differentiation and affinity.A total of229bands were amplified based on27SSR markers,of which213bands were polymorphic(93.01%).Based on SSR data,the Dice genetic similarities coefficient ranged from0.479to0.981,with an average of0.670.The GS coefficients among StHY species ranged from0.544-0.981(average0.722),while StStY species ranged from0.509-0.899(average0.700),StStH species from0.530-0.843(average0.663)and StHH species from0.550-0.827(average0.677).The results revealed abundant genetic variation and differentiation among the species studied.Moreover,clustering based on the unweighted pair group with arithmetic mean method showed that species with the same or similar genomic constitution could be grouped together.However,some species with the same genomic constitution were highly differentiated.Those with the StHY genome divided into three distinct types,with these types also corresponding with species’morphology.The results indicate that the genomic constitution of hexaploid species of Elymus in China are of the StHY type.Overall,the results showed that there is rich genetic diversity and differen
作者
陈仕勇
马啸
张新全
陈智华
周青平
CHEN Shi-yong;MA Xiao;ZHANG Xin-quan;CHEN Zhi-hua;ZHOU Qing-ping(College of Life Science and Technology, Southwest Minzu University, Chengdu 610041, China;Department of Grassland Science, Sichuan Agricultural University, Chengdu 611130, China;Institute of Qinghai-Tibet Plateau, Southwest Minzu University, Chengdu 610041, China)
出处
《草业学报》
CSCD
北大核心
2018年第9期142-151,共10页
Acta Prataculturae Sinica
基金
西南民族大学中央高校基本科研业务专项基金项目(2017NZYQN06)
国家重点研发项目(2017YFC0504806)
国家牧草产业技术体系(CARS-34)
四川省教育厅创新团队(14TD0049)资助
