Un Franais qui se rend au Québec pour la première fois sera parfois dérouté par une expression qui ne lui est pas familière.Il s'agit pourtant souvent des mêmes mots mais employ...Un Franais qui se rend au Québec pour la première fois sera parfois dérouté par une expression qui ne lui est pas familière.Il s'agit pourtant souvent des mêmes mots mais employés de faon différente.展开更多
Un Franais qui se rend au Québec pour la première fois sera parfois dérouté par une expression qui ne lui est pas familière.Il s'agit pourtant souvent des mêmes mots mais employ...Un Franais qui se rend au Québec pour la première fois sera parfois dérouté par une expression qui ne lui est pas familière.Il s'agit pourtant souvent des mêmes mots mais employés de faon différente.展开更多
鳈属(Sarcocheilichthys)鱼类是东亚地区常见小型淡水鱼类,并具有一定的养殖开发潜力。深入了解鳈属鱼类的遗传结构及其地域变异,对科学制定保护计划和可持续利用野生资源具有重要意义。试验采用鳈属鱼类包括小鳈(S.parvus,XQ)20尾,江西...鳈属(Sarcocheilichthys)鱼类是东亚地区常见小型淡水鱼类,并具有一定的养殖开发潜力。深入了解鳈属鱼类的遗传结构及其地域变异,对科学制定保护计划和可持续利用野生资源具有重要意义。试验采用鳈属鱼类包括小鳈(S.parvus,XQ)20尾,江西鳈(S.kiangsiensis,JXQ)20尾,黑鳍鳈(S.nigripinnis,HQQ)20尾,东北鳈(S.lacustris,DBQ)24尾,华鳈(S.sinensis)淮河群体(HQ_(HH))20尾、闽江群体(HQ_(MJ))17尾、江西群体(HQ_(JX))15尾和建德群体(HQ_(JD))17尾,并对每个群体的线粒体细胞色素C氧化酶亚基Ⅰ(cytochrome C oxidase subunitⅠ,COI)序列片段进行了测序和分析。试验结果表明,在获得的153个样本序列(668 bp)中,保守位点507个,变异位点154个,简约信息位点150个,碱基缺失或插入位点27个,平均转换与颠换比值为5.2。HQQ群体的单倍型多样性(Hd)最低(0.442),HQHH群体的Hd略高于HQQ群体(0.574),DBQ群体的Hd则稍高于HQHH群体(0.707),而XQ群体的Hd最高(0.963),HQMJ和HQJX群体的Hd则略低于XQ群体(0.860、0.848)。核苷酸多样变化趋势则与Hd结果类似。153尾个体定义了56种单倍型,各群体的单倍型网络中均存在各自群体的主要单倍型,如Hap_2、Hap_33和Hap_37等。基于遗传距离构建的UPGMA分子系统发育树、层次聚类树和NeighborNet分子系统发育网络表明,XQ、HQQ、JXQ和其他鳈属鱼类间遗传关系较远,而DBQ与HQHH群体间遗传关系较近。该研究利用COI序列片段评估了4个华鳈地理群体及其他4种鳈属鱼类的遗传多样性。研究结果将有助于了解华鳈不同地理群体及其他4种鳈属鱼类野生资源的遗传多样性现状,为今后华鳈以及其他4种鳈属鱼类种质资源保护及利用提供参考。展开更多
条形码数据库是开展基于DNA的生物监测关键先决条件。为在珠江流域有效开展基于DNA的生物监测,迫切需要了解物种DNA条形码的覆盖或空缺状况。整理了珠江流域常见鱼类和大型底栖动物的物种清单,从National Center and Biotechnology Info...条形码数据库是开展基于DNA的生物监测关键先决条件。为在珠江流域有效开展基于DNA的生物监测,迫切需要了解物种DNA条形码的覆盖或空缺状况。整理了珠江流域常见鱼类和大型底栖动物的物种清单,从National Center and Biotechnology Information (NCBI)数据库中检索了物种清单的DNA条形码序列,分析了常见鱼类(包括线粒体组和12s rRNA基因)和大型底栖动物(包括线粒体组、COI和18s rRNA基因)的DNA条形码覆盖范围和空缺程度。数据分析表明:(1)珠江流域共记录了常见鱼类221种,隶属于2纲18目51科和137属;常见大型底栖动物105种/属,隶属于6纲14目53科。(2)共检索到常见鱼类线粒体组序列913条和12s rRNA基因序列962条,分别占总物种的81.45%和57.92%;有12.67%的物种没有线粒体组和12s rRNA基因序列,若将条形码阈值设置为至少包含5个参考序列,则空缺度上升至52.94%;(3)共检索到常见大型底栖动物线粒体组65条序列、COI基因26,988条序列和18s rRNA基因175条序列,分别占总种/属数的29.52%、68.57%和37.14%;有25.71%的种/属在线粒体组、COI和18s rRNA基因区域皆无序列收录,若将条形码阈值设置为至少包含5个参考序列,则空缺度上升至41.90%。总之,本研究将为珠江流域开展基于DNA的鱼类和大型底栖动物监测提供基础数据支撑,为完善珠江本土DNA条形码数据库提供参考建议。展开更多
本文记述了在广西临桂县会仙镇燕子洞顶壁采集到的一种陆生蛭类。综合形态学观察、线粒体COI基因序列比对和系统发育分析,将其鉴定为山蛭科中国洞蛭属的武陵洞蛭(Sinospelaeobdella wulingensis),这是该属在广西境内的首次报道。This pa...本文记述了在广西临桂县会仙镇燕子洞顶壁采集到的一种陆生蛭类。综合形态学观察、线粒体COI基因序列比对和系统发育分析,将其鉴定为山蛭科中国洞蛭属的武陵洞蛭(Sinospelaeobdella wulingensis),这是该属在广西境内的首次报道。This paper describes a species of terrestrial leeches collected from the top wall of Yanzi Cave in Huixian Town, Lingui County, Guangxi. Based on morphological observation, mitochondrial COI gene sequence comparison and phylogenetic analysis, it was identified as Sinospelaeobdella wulingensis of the genus Sinospelaeobdella in Haemadipsidae. It was the first record of this genus in Guangxi.展开更多
Objective:To address the phylogenetic and phylogeographic relationship between different lineages of Anopheles(An.)subpictus species complex in most parts of the Asian continent by maximum utilization of Internal Tran...Objective:To address the phylogenetic and phylogeographic relationship between different lineages of Anopheles(An.)subpictus species complex in most parts of the Asian continent by maximum utilization of Internal Transcriber Spacer 2(ITS2)and cytochrome C oxidase I(COI)sequences deposited at the GenBank.Methods:Seventy-five ITS2,210 COI and 26 concatenated sequences available in the NCBI database were used.Phylogenetic analysis was performed using Bayesian likelihood trees,whereas median-joining haplotype networks and time-scale divergence trees were generated for phylogeographic analysis.Genetic diversity indices and genetic differentiation were also calculated.Results:Two genetically divergent molecular forms of An.subpictus species complex corresponding to sibling species A and B are established.Species A evolved around 37-82 million years ago in Sri Lanka,India,and the Netherlands,and species B evolved around 22-79 million years ago in Sri Lanka,India,and Myanmar.Vietnam,Thailand,and Cambodia have two molecular forms:one is phylogenetically similar to species B.Other forms differ from species A and B and evolved recently in the above mentioned countries,Indonesia and the Philippines.Genetic subdivision among Sri Lanka,India,and the Netherlands is almost absent.A substantial genetic differentiation was obtained for some populations due to isolation by large geographical distances.Genetic diversity indices reveal the presence of a long-established stable mosquito population,at mutation-drift equilibrium,regardless of population fluctuations.Conclusions:An.subpictus species complex consists of more than two genetically divergent molecular forms.Species A is highly divergent from the rest.Sri Lanka and India contain only species A and B.展开更多
文摘Un Franais qui se rend au Québec pour la première fois sera parfois dérouté par une expression qui ne lui est pas familière.Il s'agit pourtant souvent des mêmes mots mais employés de faon différente.
文摘Un Franais qui se rend au Québec pour la première fois sera parfois dérouté par une expression qui ne lui est pas familière.Il s'agit pourtant souvent des mêmes mots mais employés de faon différente.
文摘鳈属(Sarcocheilichthys)鱼类是东亚地区常见小型淡水鱼类,并具有一定的养殖开发潜力。深入了解鳈属鱼类的遗传结构及其地域变异,对科学制定保护计划和可持续利用野生资源具有重要意义。试验采用鳈属鱼类包括小鳈(S.parvus,XQ)20尾,江西鳈(S.kiangsiensis,JXQ)20尾,黑鳍鳈(S.nigripinnis,HQQ)20尾,东北鳈(S.lacustris,DBQ)24尾,华鳈(S.sinensis)淮河群体(HQ_(HH))20尾、闽江群体(HQ_(MJ))17尾、江西群体(HQ_(JX))15尾和建德群体(HQ_(JD))17尾,并对每个群体的线粒体细胞色素C氧化酶亚基Ⅰ(cytochrome C oxidase subunitⅠ,COI)序列片段进行了测序和分析。试验结果表明,在获得的153个样本序列(668 bp)中,保守位点507个,变异位点154个,简约信息位点150个,碱基缺失或插入位点27个,平均转换与颠换比值为5.2。HQQ群体的单倍型多样性(Hd)最低(0.442),HQHH群体的Hd略高于HQQ群体(0.574),DBQ群体的Hd则稍高于HQHH群体(0.707),而XQ群体的Hd最高(0.963),HQMJ和HQJX群体的Hd则略低于XQ群体(0.860、0.848)。核苷酸多样变化趋势则与Hd结果类似。153尾个体定义了56种单倍型,各群体的单倍型网络中均存在各自群体的主要单倍型,如Hap_2、Hap_33和Hap_37等。基于遗传距离构建的UPGMA分子系统发育树、层次聚类树和NeighborNet分子系统发育网络表明,XQ、HQQ、JXQ和其他鳈属鱼类间遗传关系较远,而DBQ与HQHH群体间遗传关系较近。该研究利用COI序列片段评估了4个华鳈地理群体及其他4种鳈属鱼类的遗传多样性。研究结果将有助于了解华鳈不同地理群体及其他4种鳈属鱼类野生资源的遗传多样性现状,为今后华鳈以及其他4种鳈属鱼类种质资源保护及利用提供参考。
文摘条形码数据库是开展基于DNA的生物监测关键先决条件。为在珠江流域有效开展基于DNA的生物监测,迫切需要了解物种DNA条形码的覆盖或空缺状况。整理了珠江流域常见鱼类和大型底栖动物的物种清单,从National Center and Biotechnology Information (NCBI)数据库中检索了物种清单的DNA条形码序列,分析了常见鱼类(包括线粒体组和12s rRNA基因)和大型底栖动物(包括线粒体组、COI和18s rRNA基因)的DNA条形码覆盖范围和空缺程度。数据分析表明:(1)珠江流域共记录了常见鱼类221种,隶属于2纲18目51科和137属;常见大型底栖动物105种/属,隶属于6纲14目53科。(2)共检索到常见鱼类线粒体组序列913条和12s rRNA基因序列962条,分别占总物种的81.45%和57.92%;有12.67%的物种没有线粒体组和12s rRNA基因序列,若将条形码阈值设置为至少包含5个参考序列,则空缺度上升至52.94%;(3)共检索到常见大型底栖动物线粒体组65条序列、COI基因26,988条序列和18s rRNA基因175条序列,分别占总种/属数的29.52%、68.57%和37.14%;有25.71%的种/属在线粒体组、COI和18s rRNA基因区域皆无序列收录,若将条形码阈值设置为至少包含5个参考序列,则空缺度上升至41.90%。总之,本研究将为珠江流域开展基于DNA的鱼类和大型底栖动物监测提供基础数据支撑,为完善珠江本土DNA条形码数据库提供参考建议。
文摘本文记述了在广西临桂县会仙镇燕子洞顶壁采集到的一种陆生蛭类。综合形态学观察、线粒体COI基因序列比对和系统发育分析,将其鉴定为山蛭科中国洞蛭属的武陵洞蛭(Sinospelaeobdella wulingensis),这是该属在广西境内的首次报道。This paper describes a species of terrestrial leeches collected from the top wall of Yanzi Cave in Huixian Town, Lingui County, Guangxi. Based on morphological observation, mitochondrial COI gene sequence comparison and phylogenetic analysis, it was identified as Sinospelaeobdella wulingensis of the genus Sinospelaeobdella in Haemadipsidae. It was the first record of this genus in Guangxi.
文摘Objective:To address the phylogenetic and phylogeographic relationship between different lineages of Anopheles(An.)subpictus species complex in most parts of the Asian continent by maximum utilization of Internal Transcriber Spacer 2(ITS2)and cytochrome C oxidase I(COI)sequences deposited at the GenBank.Methods:Seventy-five ITS2,210 COI and 26 concatenated sequences available in the NCBI database were used.Phylogenetic analysis was performed using Bayesian likelihood trees,whereas median-joining haplotype networks and time-scale divergence trees were generated for phylogeographic analysis.Genetic diversity indices and genetic differentiation were also calculated.Results:Two genetically divergent molecular forms of An.subpictus species complex corresponding to sibling species A and B are established.Species A evolved around 37-82 million years ago in Sri Lanka,India,and the Netherlands,and species B evolved around 22-79 million years ago in Sri Lanka,India,and Myanmar.Vietnam,Thailand,and Cambodia have two molecular forms:one is phylogenetically similar to species B.Other forms differ from species A and B and evolved recently in the above mentioned countries,Indonesia and the Philippines.Genetic subdivision among Sri Lanka,India,and the Netherlands is almost absent.A substantial genetic differentiation was obtained for some populations due to isolation by large geographical distances.Genetic diversity indices reveal the presence of a long-established stable mosquito population,at mutation-drift equilibrium,regardless of population fluctuations.Conclusions:An.subpictus species complex consists of more than two genetically divergent molecular forms.Species A is highly divergent from the rest.Sri Lanka and India contain only species A and B.