摘要
芦苇(Phragmites australis)为全球广泛分布的多型种,在水生生态系统,尤其是湿地生态系统中承担重要的生态功能,准确划分其生态型可为种质资源保护与利用提供理论依据,同时也为修复受损生态系统异地引种提供参考。利用叶绿体DNA rpl16基因序列,选取淡水湖泊较为集中且地理跨度较大的长江中下游和云贵高原,以地理位置为划分指标,探讨19个湖滨带芦苇居群的亲缘关系、遗传多样性和遗传结构,并分析了不同湖泊芦苇形态差异与遗传差异的异同,旨在分子水平为不同地理区域芦苇生态型的划分提供遗传分化方面的证据。结果表明:(1)rpl16基因序列分析显示:长江中下游芦苇居群基因水平上的变异程度较云贵高原的低;(2)基于rpl16基因序列重建的最简约系统发育树显示:以地理区域为划分指标,可将长江中下游和云贵高原的芦苇居群分为两个单系;(3)云贵高原芦苇居群的核苷酸多样性A=0.00047,单倍型多态性Hd=0.466,其遗传多样性显著高于长江中下游(Pi=0,Hd=0);(4)居群水平上的遗传分化系数Fst=0.535 37,其中53.54%的遗传变异来自于不同地理区域居群间,长江中下游芦苇居群的遗传差异指数Fst=0.537 24,基因流Nm=0.215 34,云贵高原芦苇居群的遗传差异指数Fst=0.532 78,基因流Nm=0.21923,居群间的遗传分化较强烈。分析结果证明了两种地理生态型芦苇具有遗传上的差异,且地理隔离可能是引起差异的主要原因。
Phragmites australis is a globally distributed plant,and has formed various ecologic types.It plays a crucial role in maintaining ecological functions in aquatic ecosystems,especially in wetlands.The ecological types classification of Phragmites australis accurately can provide a theoretical basis for the protection and utilization of it,and also provide references for the restoration of aquatic ecosystems.Samples from the middle and lower reaches of the Yangtze River and the Yunnan-Guizhou Plateau where freshwater lakes are concentrated and geographically wide were collected.Fifty-five samples from 19 Phragmites australis populations were used to explore their genetic distances based on the rpl16 gene sequences of chloroplast DNA.The Phenotypic differences of Phragmites australis from different populations were also compared.The results indicated that:(1)Sequence analysis of the rpl16 gene showed that the genetic variation of samples from the Yunnan-Guizhou Plateau level was more higher than those from the the middle and lower reaches of the Yangtze River;(2)Maximum parsimony tree reconstructed based on the rpl16 gene sequences showed that the Phragmites australis populations can be divided into two monographies according to different geographical region;And(3)the genetic diversity of Phragmite.s australis populations from the Yunnan-Guizhou plateau(Pi=0.000 47,Hd=0.466)is significantly higher than that from the middle and lower reaches of the Yangtze River(Pi=0,Hd=0);And(4)at population level,the genetic differentiation index(Fst) was 0.535 37.Results of analysis of molecular variance(AMOVE)demonstrated that the percentage of variation among different geographical populations was 53.54%.The genetic difference indexes of Phragmites australis population in the middle and lower reaches of the Yangtze River and Yunnan-Guizhou Plateau were 0.537 24 and 0.532 78,respectively,and the gene flow(Nm)were 0.215 34 and 0.219 23,respectively.Our analysis demonstrates that the two geographical ecotypes of Phragmites australis have genetic differences,and geographical isolation may be the main cause of the differences.
作者
胡思文
何汝嘉
周淇
王树人
黄睿
曹新益
丁浩
曾巾
赵大勇
HU Siwen;HE Rujia;ZHOU Qi;WANG Shuren;HUANG Rui;CAO Xinyi;DING Hao;ZENG Jin;ZHAO Dayong(State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering/Joint International Research Laboratory of Global Change and Water Cycle/Hohai University, Nanjing 210098, China;State Key Laboratory of Lake Science and Environment/Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China;The Experimental Teaching Center of Water Resources of Hohai University, Hohai University, Nanjing 210098, China)
出处
《生态环境学报》
CSCD
北大核心
2019年第7期1379-1387,共9页
Ecology and Environmental Sciences
基金
国家重点研发计划项目(2016YFC0402710)
国家自然科学基金项目(41871096)
江苏省自然科学基金项目(BK20181311)
中国博士后科学基金项目(2018M642147)
中央高校基本科研业务费专项资金项目(2019B17814)
河海大学水文水资源与水利工程科学国家重点实验室“一带一路”水与可持续发展科技基金项目(2018490211)
关键词
芦苇
rpl16基因序列
系统发育
遗传多样性
遗传距离
Phragmites australis
rpl16 gene sequence
genetic relationship
genetic diversity
genetic distance
