山胡椒基因组大小的估测及其重要自然群体的倍性鉴定  

Estimation of Genome Size of Lindera glauca and Ploidy Identification of Wild Individuals in Important Populations

作　　者：熊彪 彭娟 杨永仪 Xiong Biao;Peng Juann;Yang Yongyi(College of Tea Science,Guiyang,550025)

机构地区：[1]贵州大学茶学院,贵阳550025

出　　处：《分子植物育种》2023年第7期2132-2143,共12页Molecular Plant Breeding

基　　金：国家自然科学基金项目(31900272);贵州省教育厅青年人才项目(黔教合KY字[2021]084);贵州大学人才引进项目(2018-09)共同资助。

摘　　要：山胡椒是一种果实富含油脂、根茎叶具较高药用价值的经济树种。现阶段山胡椒基本处于野生状态,分析山胡椒的基因组大小特征及自然群落个体倍性,对促进该物种种质挖掘利用具有重要意义。本研究通过流式细胞术和K-mer频数分析两种方法对山胡椒基因组大小进行预测,并利用前者分析三个山胡椒自然群体(河南鸡公山,贵州梵净山和台湾地区大肚山)的个体倍性。流式细胞术以山苍子(2n=2x=24)作为内标。K-mer频数分析通过对其基因组DNA进行Illumina测序,得到过滤数据218.64 Gb。流式细胞实验结果显示,山胡椒基因组大小约为2.32 Gb,而K-mer频数分析显示其基因组大小约为2.22 Gb,杂合率为1.42%,重复率为76.75%。本研究共检测了123份个体,获得结果118份,结果显示全为二倍体。综合两种分析方法,本研究认为山胡椒是高杂合、高重复物种,基因组大小为2.22~2.32 Gb。个体倍性鉴定结果表明,不论是有性生殖还是孤雌生殖,中国境内的山胡椒野生型个体基本为二倍体,自然种群倍性处于稳定状态。研究结果可为后续山胡椒的基因组学、生殖学研究与利用等相关工作提供参考。Lindera glauca is a tree of economic whose fruits are rich in oil used in industry and extracts from roots,stems,and leaves have high application value in medicine industries.It is significant to study the genome size and characteristics of L.glauca and ploidy identification of individuals of wild populations for futhering the exploitation and utilization of its germplasm resources.Estimation of genome size of L.glauca was performed us-ing flow cytometry and K-mer analysis.Ploidy identification of individual in three populations,Jigongshan in He-nan,Fanjinshan in Guizhou,and Dadushan in Taiwan,was performed using flow cytometry.Litsea cubeba(2n=2x=24)was selected as the internal standard in the experiment of flow cytometry.For K-mer analysis,Illumina Hiseq was used to sequence L.glauca genome,and clean data were 218.64 Gb.The results of flow cytometry and K-mer analysis showed that the genome size of L.glauca was 2.32 Gb and 2.22 Gb,respectively,with 1.42%heterozygos-ity and 76.75%duplication.Total 118 samples of all 123 individuals were identified as diploid.Combining results of flow cytometry and K-mer analysis,this study concluded that L.glauca was a highly heterozygous and duplicated species with a genome size of 2.22~2.32 Gb.The results of ploidy identification of individuals indicated that wild L.glauca in China were diploid,and the ploidy of wild populations were stable,regardless of sexual reproduction or apomixis.The results can provide a reference for genomics,reproductive research and scientific utilization of L.glauca in future.

关 键 词：山胡椒 流式细胞术 全基因组调查 K-mer分析 倍性鉴定 

分 类 号：S573.9[农业科学—作物学]