42 resultados para Genetic distance


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Swertia przewalskii Pissjauk. (Gentianaceae) is a critically endangered and endemic plant of the Qinghai-Tibet Plateau in China. RAPD and ISSR analyses were carried out on a total of 63 individuals to assess the extent of genetic variation in the remaining three populations. Percentage of polymorphic bands was 94% (156 bands) for RAPD and 96% (222 bands) for ISSR. A pairwise distance measure calculated from the RAPD and ISSR data was used as input for analysis of molecular variance (AMOVA). AMOVA indicated that a high proportion of the total genetic variation (52% for RAPD and 56% for ISSR) was found among populations; pairwise Phi(ST) comparisons showed that the three populations examined were significantly different (p < 0.001). Significant genetic differentiation was found based on different measures (AMOVA and Hickory theta(B)) in S. przewalskii (0.52 on RAPD and 0.56 on ISSR; 0.46 on RAPD and 0.45 on ISSR). The differentiation of the populations corresponded to low average gene flow (0.28 based on RAPD and 0.31 based on ISSR), whereas genetic distance-based clustering and coalescent-based assignment analyses revealed significant genetic isolation among populations. Our results indicate that genetic diversity is independent of population size. We conclude that although sexual reproduction and gene flow between populations of S. przewalskii are very limited, they have preserved high levels of genetic diversity. The main factors responsible for the high level of difference among populations are the isolation and recent fragmentation under human disturbance.

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杜鹃花属(Rhododendron L.)植物分布广泛,研究发现所有的杜鹃花科植物都能形成一种特殊的菌根——杜鹃花类菌根(Ericoid Mycorrhiza)。杜鹃花类菌根对杜鹃花科植物在营养胁迫的环境下生长起到重要的作用。近几年,对杜鹃花类菌根的生物学和生态功能的研究越来越重视。我国是杜鹃花属植物资源最为丰富的国家,因此研究杜鹃花属植物菌根真菌多样性,充分利用杜鹃花特有的菌根资源,促进杜鹃花迁地保护成功具有重大的意义。 本研究以分布较广并且是中国特有的杜鹃花属植物——大白花杜鹃(Rhododendron decorum Franch.)的野生植株为研究对象,应用直接扩增根中真菌ITS区的分子鉴定方法和T-RFLP(末端限制性片段长度多态性)的分析方法,来研究其菌根真菌的多样性;并结合生态化学计量学特征分析、宿主遗传相似性及其群落组成分析等内容,探讨大白花杜鹃的菌根真菌-宿主植物-根际土壤三者之间的关系。主要结果如下: (1)通过用直接扩增真菌ITS区序列,揭示了大白花杜鹃根部真菌的多样性,本研究发现,野生大白杜鹃根部的真菌种类比较丰富,至少有26个ITS-taxa,包括子囊菌和担子菌共5个真菌目:Helotiales、Lecanorales(≡Agyriales)、Onygenales、Sebacinales和Thelephorales,其中包括典型的ERM真菌——树粉孢属Oidiodendron sp.(Myxotrichaceae)真菌。另外还发现了黑色有隔内生菌(Dark septate endophyte,DSE)以及一些未命名的子囊菌。担子菌在本研究中占有较大比例,尤其是蜡壳耳菌目真菌;此外还有较典型的外生菌根真菌——革菌目真菌。 (2)大白花杜鹃野生植株与栽培植株在菌根真菌种类组成上,有一定的相似性;在忽略种源差异等条件下相较而言,前者的物种丰富度远高于后者。 (3)大白花杜鹃菌根真菌多样性和丰富度同它的根际土壤与叶片的C、N、P含量以及C/N、N/P、土壤pH值、宿主的海拔高度等都没有显著的相关关系。 (4)在大白花杜鹃的菌根真菌群落组成方面,整体上保持了相当程度的相似性,同时还保持了一定水平的差异;大白杜鹃菌根真菌的种类是丰富的,优势度指数表明其多样性水平很高。 (5)大白花杜鹃的遗传距离与其菌根真菌群落组成结构有极显著的相关关系,宿主的种内遗传差异可能对菌根真菌群落物种组成产生选择偏好。 (6)大白花杜鹃的群落组成与其菌根真菌群落组成有极为显著的关联性,伴生种的菌根类型可能会影响宿主植物菌根真菌的物种组成结构。

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Mitochondrial DNA, purified from 36 samples of 23 local populations which are widely distributed in Vietnam, Burma, and 10 provinces of China, has been analyzed to model the phylogeny of rhesus monkeys. The 20 local populations of China may represent nearly all major populations in China. Using 20 restriction endonucleases of 6-bp recognition, we observed a total of 50-61 sites in the various samples. By combining the cleavage patterns for each enzyme, the 36 samples were classified into 23 restriction types, each of which was found exclusively in the respective population from which samples were obtained By combining the earlier study of Indian rhesus monkeys, phylogenetic trees, which have been constructed on the basis of genetic distance, indicate that rhesus monkeys in China, Vietnam, India, and Burma can be divided into seven groups. Integrating morphological and geographical data, we suggest that rhesus monkeys in China, Vietnam, and Burma may be classified into six subspecies-M. m. mulatta, M. m. brevicaudus, M. m. lasiotis, M. m. littoralis, M. m. vestita, and M. m. tcheliensis-and rhesus monkeys in India may be another valid subspecies. M. m. tcheliensis is the most endangered subspecies in China. Divergence among subspecies may have begun 0.9-1.6 Ma. The radiation of rhesus monkeys in China may have spread from the southwest toward the east. The taxonomic status of the Hainan monkey and the Taiwan monkey require further investigation.

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Six sample specimens of Trachypithecus francoisi and 3 of T. leucocephalus were analyzed by use of allozyme electrophoresis and random amplified polymorphism DNA (RAPD) in order to clarify the challenged taxonomic status of the white-head langur. Among the 44 loci surveyed, only 1 locus (PGM-2) was found to be polymorphic. Nei's genetic distance was 0.0025. In total, thirty 10-mer arbitrary primers were used for RAPD analysis, of which 22 generated clear bands. Phylogenetic trees were constructed based on genetic distances using neighbor-joining and UPGMA methods. The results show that T. francoisi and T: leucocephalus are not monophyletic. T. francoisi from Guangxi, China and Vietnam could not be clearly distinguished, and they are not divided into 2 clusters. A t-test was performed to evaluate between genetic distances within and between T. leucocephalus and T. francoisi taxa groups. The statistical test shows that the taxa group within T: leucocephalus and T: francoisi does not significantly differ from that between T: leucocephalus and T: francoisi at the 5% level. Our results suggest that the level of genetic differentiation between T, leucocephalus and T. francoisi is relatively low. Recent gene flow might exist between T. francoisi and T. leucocephalus. Combining morphological features, geographical distribution, allozyme data, RAPD data, and mtDNA sequences, we suggest that the white-head langur might be a subspecies of T. francoisi.

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采用不连续垂直板聚丙烯酰胺凝胶电泳技术,对河曲藏獒、青海藏獒、青海藏狮犬和青海土种犬共4个群体103只犬的9个血液蛋白基因座(Tf、Po、Es-1、Es-2、Sα_2:、Hb、Alb、Pr、Amy)的多态性进行了检测,分析了两个藏獒群体的群体内和群体间的遗传变异,并以Nei氏标准遗传距离(D)为基础用UPGMA法探讨了不同犬群之间的遗传关系.结果表明,在4个被测犬群中,Tf、Po、Es-1、Es-2和Sα_2 5个基因座上存在多态性,其中Tf、Es-1和Po分别由3个等住基因所控制,Es-2和Sα_2,分别由2个等位基因所控制,而Hb、Alb、Pr和Amy基因座均呈现单态;河曲藏獒群体内遗传变异较青海藏獒丰富,而两个藏獒群体间的遗传分化程度很低(G_(ST)=0.0187);以Nei氏标准遗传距离(D)为基础的UPGMA法聚类结果表明.青海藏獒与青海藏狮犬和青海土种犬的遗传关系近于河曲藏獒.

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Gymnodiptychus integrigymnatus is a critically endangered species endemic to the Gaoligongshan Mountains. It was thought to be only distributed in several headwater-streams of the Longchuanjiang River (west slope of the Gaoligongshan Mountains, belonging to the Irrawaddy River drainage). In recent years, dozens of G. integrigymnatus specimens have been collected in some streams on the east slope of the Gaoligongshan Mountains (the Salween drainage). We performed a morphological and genetic analyses (based on cytochrome b and D-loop) of the newly discovered populations of G. integrigymnatus to determine whether the degree of separation of these populations warrants species status. Our analysis from the cytochrome b gene revealed that nine individuals from the Irrawaddy drainage area and seven individuals from the Salween drainage area each have only one unique haplotype. The genetic distance between the two haplotypes is 1.97%. Our phylogenetic analysis revealed that G. integrigymnatus is closely related to highly specialized schizothoracine fishes. Analysis from the mitochondrial control region revealed that G. integrigymnatus has relatively high genetic diversity (pi was 0.00891 and h was 0.8714), and individuals from different river drainages do not share the same haplotypes. The AMOVA results indicated 87.27% genetic variability between the Salween and Irrawaddy populations. Phylogenetic trees show two major geographic groups corresponding to the river systems. We recommend that G. integrigymnatus should be considered as a high priority for protected species status in the Gaoligongshan Mountains National Nature Reserve, and that the area of the Gaoligongshan Mountains National Nature Reserve should be expanded to cover the entire distribution of G. integrigymnatus. Populations of G. integrigymnatus from different river systems should be treated as evolutionarily significant units.

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Twelve restriction endonucleases were employed to analyze the mitochondrial DNA of four species of muntjacs and two related species of deer: red muntjac (M. muntjak), Gongshan muntjac (M. gongshanensis), black muntjac (M. crinifrons), Chinese muntjac (M. reevesi), tufted deer (Elaphodus cephalophus), and forest musk deer (Moschus berezovskii). A total of 170 restriction fragments were detected among the samples. Fragments data were used to calculate the genetic distance (i.e. percent sequence divergency) among species, which in turn were used to construct a phylogenetic tree and to estimate divergency times. Our analysis indicates that the black muntjac and the Gongshan muntjac are most closely related, and that they are closely realted to the red muntjac and the Chinese muntjac. Additionally, the tufted deer is genetically closer to muntjacs than the musk deer is.

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The diversity of gynogenetic, artificial sex reversal and natural silver carp and bighead carp is examined using randomly amplified polymorphic DNA (RAPD) method. All of the 187 bands are obtained and 19 (10.16%) of them are polymorphic in gynogenetic silver carp. Meanwhile 32 (15.61%) out of 205 bands are polymorphic in control group. In gynogenetic bighead carp a total of 232 bands are identified and 11 (4.74%) out of them are polymorphic, while 25 (10.37%) out of 241 bands are polymorphic in control group. The genetic distance of four populations is calculated and it is 0.102 and 0.023 for gynogenetic silver carp and gynogenetic bighead carp respectively. The values of natural silver carp and bighead carp are 0.161 and 0.104. From the UPGMA trees constructed based on genetic distance, the sex reversal individuals that match with the gynogenetic female individuals are picked out. A new breeding process of establishing a pure line is developed.

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青杨组(Section Tacamahaca Spach)杨树是我国重要的乡土经济树种,目前对其分子遗传变异和系统进化的研究还很少,尤其是在青杨组杨树遗传资源极为丰富的川西地区,杨树的分子进化及亲缘关系的研究极为缺乏,非常不利于该树种遗传资源的开发和利用。本研究从川西地区收集了青杨(Populus cathayana)、青海杨(P. prezewalskii)、滇杨(P. yunnanensis)、康定杨(P. kangdingensis)、西南杨(P. schneideri)、小叶杨(P.simonii)和三脉青杨(P. trinervis)这7 个青杨组树种的10 个群体,利用多种分子标记手段对其种间的亲缘关系进行比较,并结合形态和地史资料进行了全面的研究和评价,得到了如下的主要研究结果: 1. SSR 和ISSR 位点变异丰富。通过10 对引物对50 个杨树个体的DNA 样品进行了SSR 分析,所有位点展现了丰富的群体间和种间的多态性,多态位点率达到了100%,每位点的等位基因数变化范围为5 ~ 17,平均为11.9 个;通过11 条ISSR 随机引物对供试的混合DNA 样品进行分析,共检测到130 个标记,其中多态性标记为119 个,多态百分率为91.5%。研究认为,SSR 单个标记能展现高水平信息,而ISSR 单个引物能探测更多数量多态性。通过两个标记的遗传距离、聚类图和PCA 分析,表明:同一种内不同群体间的同源性最高;康定杨和西南杨有较近的亲缘关系;小叶杨和三脉青杨聚合在一起,显示了其相互较近的亲缘关系;滇杨与其它杨树种可能存在着较远的亲缘关系。 2. 采用4 对选择性引物对7 个青杨组杨树种10 个群体进行AFLP 分析,总共扩增出284 个位点,其中200 个位点显示出了多态性,多态位点百分比为70.4%,平均多态带为50 条。TE-AFLP 的分析总共扩增出192 个位点,其中139 个位点显示出了多态性,多态位点百分比为72.4%,平均多态带为34.7 条。比较的结果表明AFLP、TE-AFLP 的遗传信息含量比较接近,略小于ISSR,大约仅为SSR 的1/3;但这两个基于AFLP 的标记系统的信息探察能力也远大于ISSR 和SSR 标记系统。这两个分子标记的聚类结果,显示小叶杨、三脉青杨和滇杨三个种聚为一组,其中小叶杨与三脉青杨的亲缘关系更近;其它几个杨树种聚为一类,西南杨与青杨表现出较近的亲缘关系。 3. 所有7 对cpSSR 引物中,仅有4 个叶绿体位点在种间具有多态性,而在种内群体中并不具有多态性,共检测出13 个条带,组合成了4 种不同的单倍型;对于cpDNA的5 对引物,共检测出了73 条酶切片段,其中52 条是多态带,组合成了9 种不同的单倍型;而5 对mtDNA 通用引物未能检测出多态性的条带,表现出线粒体的保守性。叶绿体的聚类分析认为,小叶杨、三脉青杨和滇杨有较近的母性起源,且依次聚合;其余四种杨树聚为一类,并且康定杨与西南杨表现出最近的亲缘关系,并依次与青杨和青海杨聚合。 4. 根据本文的分子数据,结合形态和生境分布资料分析认为:青杨组杨树种内群体间的遗传变异程度是小于种间的遗传差异,显示了与传统分类一致的结果;三脉青杨和小叶杨有很近的亲缘关系,可能拥有相同的祖先类群;滇杨与小叶杨和三脉青杨之间具有一定的亲缘关系,特别是在其母性祖先的起源上有着一定的同源性;西南杨与青杨和康定杨均保持着较近的亲缘关系,且有可能是这两个种原始祖先杂交后所形成的。 Although western Sichuan is regarded as a natural distribution and variation center forthe Section Tacahamaca of the Populus species in China, little is currently known about themajority of poplar species occurring in this region. In the present study, molecular data wereutilized to determine the genetic relationships among Populus species in Section Tacamahacain western Sichuan including P. cathayana, P. prezewalskii, P. yunnanensis, P. kangdingensis,P. schneideri, P. simonii and P.trinervis. The results are as fellows: 1. The genetic variation at SSR and ISSR loci was abundant. All the 10 SSR loci werepolymorphic, and the number of alleles per locus varied from 5 to 17 with a mean valueequaling 11.9. Based on the 11 ISSR primers, 130 clear and reproducible DNA fragmentswere generated, of which 119 (91.5%) were polymorphic. Our results reveal that single SSRlocus can present more genetic information, while more polymorphic bands can be detectedby single ISSR primer. Moreover, the genetic distance, cluster and PCA analysisdemonstrated that: a close relationship among accessions of the same species and suggestedmonophyly in P. przewalskii and P. cathayana; P. schneideri is genetically highly similar to P.kangdingensis; P. trinervis and P. simonii have a close genetic affinity; P. yunnanensis isdistinct from the other species. 2. Genetic relationships of poplar species in Section Tacamahaca from western Sichuanwere evaluated by means of AFLP and TE-AFLP. For four AFLP primer combinations, atotal of 284 bands were obtained of which 200 (70.4%) were polymorphic with the average of50 polymorphic bands. For four TE-AFLP primer combinations, a total of 192 band wereobtained of which 139 (72.4%) were polymorphic with the average of 34.7 polymorphicbands. Our results indicate that the genetic information of AFLP is similar to that ofTE-AFLP, and little less than that of ISSR, but only about 1/3 of that of SSR. However, theability of information detection of the two AFLP-based markers is much higher than that ofISSR and SSR. In addition, the cluster analysis of AFLP, TE-AFLP and combined data revealthat: P. yunnanensis, P. trinervis and P. simonii clustered together, and P. trinervis and P.simonii showed more closed affinity; the other four poplar species clustered together, P.cathayana and P. schneideri showed more closed origin especially. 3. The cpSSR analysis for seven Populus species belonging to the Section Tacamahaca.Four out of the seven analyzed chloroplast loci were polymorphic, whereas none of the lociwere polymorphic across the accessions within a species. 13 bands and 4 different kinds ofhaplotypes were reduced. Based on 5 pairs of cpDNA primers, 73 fragments (52 polymorphic)and 9 kinds of haplotypes were produced. However, none of the polymorphic was detected bythe 5 mtDNA primer pairs, revealing conservation of mtDNA region. The cluster analysis ofcpDNA revealed that: similar maternal phylogeny among P. yunnanensis, P. trinervis and P.simonii; the other four species clustered together, P. schneideri and P. kangdingensis showedmore closed maternal lineage especially. 4. Our molecular data, morphological characters and nature habitat revealed that: sameto the traditional taxonomy assignment, genetic variation within a same Populus species islower than that among Populus species in Section Tacamahaca; P. yunnanensis may share itschloroplast ancestor with P. trinervis and P. simonii; moreover, sister genetic relationship of P.trinervis and P. simonii indicated their similar origin; P. schneideri clustered with P.kangdingensis and P. cathayana, respectively, and may have derived from an ancienthybridization event involving the ancestors of the two species.

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对隆肛蛙属的物种构成进行了订正,建立新属肛刺蛙属Yerana gen. nov.;订正后的隆肛蛙属现仅隶2种, 即隆肛蛙F. quadrana和太行隆肛蛙F. taihangnicus。运用形态学分析探讨了隆肛蛙属物种及种群的形态差异和分类关系,通过分子系统学研究探讨了隆肛蛙属物种及种群的分类和系统发育关系,运用动物地理学方法结合系统发育关系探讨了隆肛蛙属种群的地理分布格局成因与历史过程。主要结果和推论如下: 1.隆肛蛙属物种构成的订正及一新属建立 建立新属肛刺蛙属,将隆肛蛙属中的原叶氏隆肛蛙F. yei归隶新属肛刺蛙属并更名为叶氏肛刺蛙Y. yei,,新属建立的主要依据为:(1)雄性肛部隆起,肛孔下方有两个布满黑刺的大的白色球形隆起,具单咽下内声囊, 第一指具婚刺;(2)形态量度分析表明叶氏肛刺蛙与隆肛蛙和太行隆肛蛙的形态差异远大于后两者之间的差异;(3)叶氏肛刺蛙的分布区与隆肛蛙和太行隆肛蛙的分布区距离较远且呈隔离状态;(4)分子系统学研究资料(Jiang et al.,2005)证明叶氏肛刺蛙与隆肛蛙和太行隆肛蛙非单系发生;叶氏肛刺蛙在第二支中位于基部。因此,隆肛蛙属现仅隶2种,即隆肛蛙和太行隆肛蛙。 2.隆肛蛙属种群形态学研究 对隆肛蛙属中隆肛蛙和太行隆肛蛙的15个地理种群565只标本的28项形态性状进行了测量,运用典型判别分析法对其分析的结果表明:(1)太行隆肛蛙与隆肛蛙形态差异明显,支持其为不同的物种;(2)原隆肛蛙河南伏牛山种群和山西中条山种群应为太行隆肛蛙的地理种群;(3)隆肛蛙不同地理种群之间形态差异明显,其中四川安县种群、陕西周至种群和湖北利川种群与模式产地重庆巫山种群的差异可能达到了亚种或亚种以上分化水平。对隆肛蛙属量度分析的15个种群进行定性形态分析表明其分为三种形态型,对应隆肛蛙、过渡型和太行隆肛蛙,其变异特征主要为内跗褶、雄性肛部隆起及疣粒分布、第五趾外侧缘膜等,这与量度分析结果相似。 3.隆肛蛙属种群分子系统学研究 测定隆肛蛙属Feirana的2种19种群的线粒体12S rRNA和16S rRNA基因片段、ND2基因的DNA序列,比对后共计1953bps。(1)遗传多样性与距离分析:结果表明,隆肛蛙属种群具很高的遗传多样性,19个种群样品表现出19种单倍型(遗传多样性指数Hd=1.0); ND2基因的进化信息含量远高于12SrRNA和16SrRNA。隆肛蛙属2种群组内的种群间的遗传距离远小于两种群组间的距离,种群在不同基因上的遗传距离表现的关系与对应的系统树一致。(2)系统发育关系分析:结果表明,不同基因片断基于不同方法构建的隆肛蛙属种群系统发育树结构基本一致,基本表明隆肛蛙属种群为单系发生;它们在系统树中分为两大支,分别对应于隆肛蛙和太行隆肛蛙;支持中条山种群(沁水、历山和济源种群)和伏牛山种群(栾川和内乡种群)为太行隆肛蛙的地理种群,而原隆肛蛙秦岭中东段的部分种群(柞水、宁陕、长安大坝沟种群)也应为太行隆肛蛙的地理种群。(3)亚种分化分析:根据遗传距离分析和系统发育关系分析结果,并考虑形态上的差异情况以及地理分布信息,隆肛蛙所隶种群组可分为2亚种,即隆肛蛙指名亚种F. quadrana quadrana包括四川盆地东缘大巴山东段-巫山-武陵山北麓种群和秦岭中段(周至板房子和长安广货街)种群,他们在系统关系树上聚为一支;安县亚种F. quadrana anxianensis包括四川盆地西缘岷山东麓-龙门山-大巴山和秦岭西段的种群(安县、青川、文县、南江和凤县种群),他们在系统关系树上聚为一支。太行隆肛蛙所隶种群组也可分为2亚种,即太行隆肛蛙指名亚种F. taihangnicus taihangnicus包括中条山的种群(沁水、历山和济源种群)和中东秦岭的部分种群(柞水、长安大坝沟和宁陕种群),他们在系统关系树上聚为一支;太行隆肛蛙伏牛亚种F. taihangnicus funiuensis,为伏牛山地区的种群(栾川和内乡种群),他们在系统关系树上聚为一支。 4.隆肛蛙属种群动物地理学研究 隆肛蛙属19种群的分歧年代分析: 以长江巫山段和黄河三门峡段的形成历史时期为参考点,根据已测隆肛蛙属19种群及其外群包括N. pleski、P. yunnanesis、P. robertingeri、F. limnocharis的1953bps DNA序列构建分子钟,获得各支系的分歧年代。结果表明:①棘蛙族在70Ma左右开始其独立演化历程,这与Roelants et al.(2004)的分析结果~60±15Ma左右开始分化基本一致,后者印证了本文的分子钟。②隆肛蛙属的起始分化年代较早,隆肛蛙和太行隆肛蛙两种群组的最近祖先种群大概在46Ma~50Ma左右;隆肛蛙和太行隆肛蛙种群组内的种群分化年代相对两种群组间晚得多, 隆肛蛙种群组内两亚种分化起始年代约为10Ma左右,而太行隆肛蛙种群组内两亚种分化起始年代约为6Ma。 隆肛蛙属种群分布格局形成过程分析: ①隆肛蛙属的系统关系与地理分布格局密切相关,大部分系统分支分级与地理距离成正比;②隆肛蛙属最近祖先种群的分化中心可能位于秦岭中部地区, 隆肛蛙属的种群分布格局的形成表现为隔离分化与扩散相结合的机制,由隔离分化产生的隆肛蛙祖先种群主要从秦岭中部向西南方向扩散,后隔离分化为两亚种;太行隆肛蛙祖先种群向东北方向扩散也分化为两亚种。 隆肛蛙属种群分布区域地质历史的探讨:本文所建分子钟和种群分化方式印证了该区域的几次主要地质事件,包括岷山-龙门山-西秦岭等地区的快速差异隆起、第四纪冰期等。 The specific composition of the genus Feirana should be revised. A new genus Yerana gen. nov.(Ranidae:Dicroglossinae)was established based on morphological data-set and molecular phylogeny, as a result, only two species F. quadrana and F. taihangnicus are classified into Feirana now. Morphological differences and taxonomy of populations of Feirana were investigated based on morphological and morphometric data; phylogenetic relationships and taxonomy of populations of Feirana were elucidated using molecular data, and then the proceeding of the distribution pattern of populations of Feirana were discussed. The main results and conclusions and proposals were presented as following: 1. Revising of the specific composition of the genus Feirana and establishment of a new genus The new genus Yerana, only containing the type species Y. yei, was established based on the following evidences: (1) In adult male, distinct up-heaved circular vesicle presents around the anal, and under anal there are two white balls on which black spines exist, black horny spines scatter on the upper side of first finger, and internal single subgular vocal sac presents; (2) there is obvious morphometric differences between Yerana and Feirana; (3) Yerana is distributed far from Feirana; (4) evidences of molecular phylogeny(Jiang et al.,2005)suggested that Yerana take a special phylogenetic clade which is different from other genus included in the tribe Paini. As a result, there are only two species in Feirana, i.e., F. quadrana and F. taihangnicus. 2. Morphological research of populations of Feirana Twenty-eight characters of 565 individuals of 15 populations of the genus Feirana were measured, the results of Canonical Discriminant analysis of the morphometric data-set indicated that: (1) there are very prominent differences between the two species F. quadrana and F. taihangnicus. The validity of species F. taihangnicus was approved here; (2) Mt. Funiu population and Mt. Zhongtiao population should belong to the species F. taihangnicus; (3) Obvious differences exist among 12 populations of F. quadrana, the differentiation among Zhouzhi population, Anxian population, Lichuan population, and Wushan population together with the others probably reach sub-specific or specific level. Result of morphological comparison between 15 different populations show that 3 morphological types are recogenized in according with F. quadrana, F. taihangnicus and intergradation, this result conform to the result of morphometric analysis. 3. Molecular phylogenetic study on populaions of Feirana Fragment of 12SrRNA and 16SrRNA genes, and ND2 gene of 19 populations of two species of Feirana were sequenced and aligned, from which 1953 bps were received. (1) analyses of genetic distance and hereditary diversity indicated that: genetic distance between populations in each group were less than distance between two groups of Feirana, 19 haplotypes were recognized from 19 samples of 19 populations, so the hereditary diversity of populations of Feirana was very high (Hd=1.0), phylogenetic information in ND2 gene is more than fragment sequence of 12SrRNA and 16SrRNA genes. (2) Result of molecular phylogeny indicate that the phylogenetic trees constructed using different methods based on different sequence data sets showed the revised genus Feirana is monophyletic since the 19 populations of Feirana were firstly clustered together as one large clade, which was further clustered into two major clades, corresponding to F. quadrana(GroupⅠ) and F. taihangnicus(GroupⅡ), respectively. So populations of Qinshui and Lishan in Mt. Zhongtiao, populations of Luanchuan and Neixiang in Mt. Funiu, and populations of Zhashui, Dabagou of Chang’an and Ningshan in eastern Mt. Qinling should belong to the species F. taihangnicus; (3) Subspecific differentiation. on the basis of genetic distance, phylogenetic trees and geographical distribution, F. quadrana should have two subspecies, i.e., F. quadrana qudadrana, consisting of the populations Guanghuojie of Chang’an and Zhouzhi in Mid-Mt. Qinling, populations in Wushan area and northern Mt. Wuling (Lichuan), and F. qudadrana anxianensis, consisting of the populations in eastern Mt. Ming shan-Mt. Longmen-western Mt. Daba-western Mt. Qinling (Anxian, Qingchuan, Wenxian, Nanjiang and Fengxian); F. taihangnicus should also has two subspecies, i.e., F. taihangnicus taihangnicus, consisting of the populations in Mt. Zhongtiao and eastern Mt. Qinling, and F. taihangnicus funiuensis, consisting of the populations in Mt. Funiu. 4. Zoogeography of populaions of Feirana Analysis for divergent time of 19 populations of Feirana: Using the dates of run-through of Wushan segment of Changjiang River as the time when the population of Lichuan started differentiated from the populations of Wushan and Shennongjia, and the dates of Sanmenxia segment of Yellow River as the time when the populations in Mt. Zhongtiao started differentiated from the population of Dabagou in Chang’an, molecular clock was established using sequences with 1953 bps of 19 populations of Feirana and outgroup including N. pleski, P. yunnanesis, P. robertingeri, F. limnocharis in order to estimate divergent time of all clades. Result of that indicated that: ① the tribe Paini started to evolve independently at about 70Ma when is in consistent with that estimated by Roelants et al.(2004)with result of about ~60±15Ma, they were corroborated by each other, this confirms the validity of this molecular clock; ② divergent time for speciation of Feriana is early, ancestral populations of F. quadrana and F. taihangnicus were found about 46Ma~50Ma; differentiation of populations within species is greatly late to the divergence of the two species, divergent time for F. quadrana is 10Ma and divergent time for F. taihangnicus is 6Ma. Proceeding of distribution pattern of Feirana. Phylogenetic relationships of populations of Feirana matched quite with distribution pattern of them, the relationships among clades showed in phylogenetic trees is direct ratio to geographical distance of them; the estimated date of speciation between two species of Feirana was as early as speciation of Paa yunnanesis and Nanara pleski; middle part of Mt. Qinling is the center of speciation of Feirana, combination of mult-events of dispersal and vicariance are probably the mechanism of speciation of Feirana, F. quadrana colonized the mid-Mt. Qinling and then differentiated into two subspecies in southwest direction, ancestral population of F. taihangnicus colonized the mid-Mt. Qinling and then differentiated into two subspecies in northeast direction. On geological history of the distribution of Feirana. According to molecular clock and speciation model of populations of Feirana, some geological events are confirmed, including special rise of Mt. Minshan- Mt. Longmen-western Mt. Qinling, glacial age.

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依据线粒体上ND2和CO1两个变异较大的基因序列分析了香港地区香港湍蛙7种群、华南湍蛙1种群,以及大陆其他地区华南湍蛙7种群,戴云湍蛙1种群,武夷湍蛙1种群的系统发育关系,进而探讨香港湍蛙的遗传多样性、香港湍蛙特有性、如何确定香港湍蛙最佳保护单元以及这四种湍蛙的物种分类地位。 1. 香港湍蛙保护遗传学研究 香港湍蛙核苷酸传多样性较低,从其遗传多样性信息、单倍型网络分析、中性检验值以及岐点分布结果一致显示香港湍蛙很可能经历了瓶颈后的扩张,种群正在由一个较小的有效种群大小迅速增长, 有足够的时间通过变异用于积累单倍型的多态性, 而对于提高核苷酸多样化而言, 时间尚短(Nei M et al,1975,Avise J C,2000;李明等,2003)。 分子变异分析结果显示香港湍蛙种群间存在较多的基因交流,且系统发育树上各种群间交叉在一起,没有形成与地理单元相关的分支,而从其单倍型网络看,他们源于共同的祖先,是一个单系群,与地理单元间没有形成显著的遗传分化。因此应作为一个进化显著单元(ESU)。结合其与其他湍蛙发育关系及遗传距离以及野外采集信息认为香港湍蛙只在香港地区有分布,属于香港特有种。该物种内遗传多样性较低,又属于世界自然保护联盟红皮书中的近危种,同时也是《野生动物保护条例》中的受保护野生动物,且由于香港城市建设等使得其栖息环境受到威胁,因此在香港特别行政区应该受到重点保护。 从单倍型分布和核苷酸多样性可以看出大榄涌种群和城门种群具有较高的单倍型多样性和核苷酸多样性,应该作为保护的重点区域。 2. 华南湍蛙东、南沿海种群间系统关系 华南湍蛙分布广,各种群存在着丰富的遗传多样性信息且中部种群广西龙胜和湖南张家界种群核苷酸多样性明显高于其他边缘种群华南湍蛙。种群间几乎没有基因交流,且各种群间无共享单倍型,可见已形成了显著的遗传分化。各种群间遗传距离都较远,其中广东南昆山种群以及福建三港种群与其他种群距离最远,因此可以推测其他种群(广东深圳、香港大屿山、广西龙胜和防城以及湖南张家界种群)可能为独立进化的种群。但是否是一新种或一隐存种,还需要结合形态学进行更深入的研究。 本研究中无论从系统关系看还是从遗传距离看,大屿山种群与深圳种群最近,支持陈坚峰等将其定为华南湍蛙,即华南湍蛙新增一个分布点:香港大屿山。 系统树上广西防城种群(支B)与龙胜和湖南种群(支A)形成姐妹群。香港大屿山种群与深圳种群先形成姐妹群(支C),但却没有与其距离很近的广东南岭及南昆山种群(支D)形成姐妹群,可能粤北和粤中的环境及气候较复杂因此与粤南其他种群形成了明显的隔离。同时可以看出华南湍蛙种群遗传分化与地理距离没有显著的相关性。 3. 四种湍蛙间的系统关系 根据线粒体CO1基因建立四种湍蛙间的系统关系及其遗传距离,很清楚地看到,香港湍蛙与戴云湍蛙关系很近,而华南湍蛙则与武夷湍蛙较近。然而,戴云湍蛙同一个种群内部共有两个单倍型DY1和DY2,且两个单倍型间遗传距离大于DY1与香港湍蛙间遗传距离,更远远大于香港湍蛙种群内部的距离,即戴云湍蛙内部两个单倍型间遗传距离达到了种级水平,同样在系统发育树上这两个单倍型与香港湍蛙形成并系。但是,戴云湍蛙种内在形态上差异不显著。因此,其是否属于萌芽物种分化形成(budding speciation)或已经完全分化为两个不同的种值得进一步研究? 与戴云湍蛙香港湍蛙关系类似,从系统树上看华南湍蛙不形成单系,而是分成两个大支,与武夷湍蛙形成并系,且福建和南昆山的华南湍蛙与武夷湍蛙遗传距离远大于武夷湍蛙种内福建种群与浙江种群的遗传距离,达到了种级分化水平。由此,可以推断武夷湍蛙是有效种。系统树上广东深圳、香港大屿山、广西防城和龙胜以及湖南张家界种群与华南湍蛙福建及南昆山各种群间遗传距离已超出了种内各种群间的遗传距离,但是至于这一支是否应为另外一个种,有必要扩大采样,并结合核基因及形态信息进行进一步研究。 MtDNA of ND2 and CO1 gene were used to investigate genetic diversity of Amolops in Hongkong .We collected seven populations of A. hongkongensis,,one population of A.ricketti from Hong Kong and other seven populations of A.ricketti from East and South of Chinese mainland. As well as one population of A. daiyunensis and one population of A.wuyiensis Phylogenetic relationship were analyzed of four species. Discussed whether A.hongkongensis is an endemic species and how can we make the conservation and management decisions. 1. Conservation Genetics of A. hongkongensis A. hongkongensis has a low nucleotide diversity, the results of genetic diversity, haplotype network, neutrality test and the mismatch distributions indicate that A. hongkongensis experienced a recent expansion after a bottle neck. They had enough time to accumulated haplotype diversity, but it’s too short to have a high nucleotide diversity(Nei M et al,1975,Avise J C,2000;Li et al,2003). The result of AMOVA reveals that it has much gene exchange among the populations of A. hongkongensis. The clades of the phylogenetic tree were mixed together, no significant genetic differentiation among 8 populations and they share the same ancestor from the network analysis, these indicate that they are monophyly and should be protected as one ESU. Combined with the information of relationships of interspecies, genetic distance and distribution investigate, We conclude that A. hongkongensis is an endemic species of Hong Kong. Considering on the status of low genetic diversity in A.hongkongensis, and this species was listed in the IUCN red list as near threatened, as well as listed in the . Furthermore, it’s habitat loss and degradation more rapidly as the human activity got higher and higher. So it’s urgent to protect them in Hong Kong. Our results suggest that Tai Lam Wu and TAI MO Shan -Shing Mun populations have the higher priority to be protected because their higher genetic diversity. 2.Phylogenetic relationships among populations of Amolops ricketti from the Southern and eastern China A. ricketti has the considerable genetic diversity of mitochondrial haplotypes within and among populations, and Mitochondrial DNA diversity was higher in populations at the central area of the present distribution range of the frog,i. e. the Longsheng population and Zhangjiajie population, than at the edges of their distribution range. They have no share haplotype among populations, and have a significant genetic differentiation. Genetic distance is high among the populations, especially the distance of Nankun and Sangang group with others, which suggested that they evolved independently. May be there is a cryptic species or a new species, a further study is needed. The results of gene tree and the genetic distance clearly demonstrate that the population from LanTau island is A. ricketti, so we agree with Chen et al(2005) . That means A.ricketti have a new distribution site: LanTau island, HongKong. Phylogenetic relationships were analyzed through NJ and Mrbayes methods and got a consistent topological structure, the structure indicated that the ingroup were comprised four groups. Populations Longsheng and Zhangjiajie were first clustered as clade A; Populations Fangcheng was clustered together (clade B) as a sister group to clade A;Populations Shenzhen and Lantau island were sister groups and clustered as clade C;Then the clade D included populations Nankunshan and Nanling in Guangdong province and Sangang in Fujian province. 3. Phylogenetic Relationships among these four specises Phylogenetic relationships based on 1503bp CO1 gene and the genetic distance show that A. hongkongensis close to A. daiyunensis whereas A.ricketti near to A.wuyiensis. Nevertheless, there are two haplotypes in A.daiyunensis and the genetic distance between them higher than the distance between DY1 with A. hongkongensis. A. hongkongensis is nested in the paraphyletic ancestral species A. daiyunensis. Without significant difference in the morphological characters, So, we considered both A.daiyunensis and A.hongkongensis are valid species, may be this represents a case of ‘budding speciation’ like Batrachuperus pinchonii(Fu and Zeng,2008) in the population of A. daiyunensis. Just like two species above A. wuyiensis and A. ricketti are not monophyly, instead, A.wuyiensis is nested in the paraphyletic ancestral species A.ricketti. We need do more research to make sure whether they are new species.

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沙蜥属(Phrynocephalus)的卵胎生类群主要分布在我国青藏高原,包括南疆沙蜥(P. forsythii)、西藏沙蜥(P. theobaldi)、红尾沙蜥(P. erythrurus)、贵德沙蜥(P. putjatia)和青海沙蜥(P. vlangalii)。其卵胎生生殖方式适应了高寒生境,与青藏高原隆升有关。纵观前人的研究,上述几种卵胎生沙蜥的分类、系统发育关系以及生物地理都还存在疑问。本文研究了分布在若尔盖湿地的青海沙蜥红原亚种(P. v hongyuanensis)以及分布在黄河上游其它地区青海沙蜥种组的地理分布格局,并探讨了其形成机制。 青海沙蜥在黄河上游主要分布于若尔盖湿地以及青海湖周边地区。若尔盖湿地青海沙蜥红原亚种的生境由于沼泽的形成被切割成不连续的斑块,通过遗传分析可以推测这种特殊生境对它们遗传结构的影响。其次,贵德沙蜥、青海沙蜥的青海湖周边各居群以及若尔盖湿地居群之间的系统地理格局还未见报道。因此本文以居群为单位,将它们作为一个复合体,通过系统地理研究,可以了解其种群遗传结构,据此分析相关的地质历史事件对其分布的影响。主要结果如下: 1. 若尔盖湿地青海沙蜥红原亚种的种群遗传结构: 共研究了三个地理单元(红原(HY)、辖曼(XM)、玛曲(MQ))的7个采集点的72个个体。所有ND4-tRNALeu序列比对得到785 bp的片断,定义了9种单倍型。结果显示总的核苷酸多样性较低,单倍型多样性较高。分子变异分析(AMOVA)显示3个单元间差异显著(P<0.01),遗传变异主要存在于地理单元间,占62.61%。除MQ单元,XM各居群与HY居群混杂在一起,单倍型网络图没有显示出单倍型和地理位置的对应关系。XM单元单倍型的不配对分布(Mismatch distribution)为明显左移的单峰,且Fu’s Fs test为负值,表明XM单元可能经历了近期种群扩张,有足够的时间积累单倍型的多态性,还不足以大幅提高核苷酸多样性,这是其单倍型多样性较高和核苷酸多样性较低的原因。MQ单元遗传多样性低而与其他单元显著分化,推测这与3万年前黄河在若尔盖玛曲之间贯通有关。近期沼泽的形成对XMb居群的隔离时间短,使得其遗传多样性低但还不足以形成大的遗传差异。无论黄河的贯通还是沼泽的形成其隔离形成的时间都不长,其作用改变了单倍型出现的频率,也出现了一些特有单倍型,但共享单倍型还广泛存在,还不足以使得不同居群之间形成较大的遗传距离。 2. 黄河上游青海沙蜥种组的分布格局与地史过程的关系: 黄河上游青海沙蜥种组包括贵德沙蜥、青海沙蜥指名亚种的青海湖周边各居群、青海沙蜥红原亚种若尔盖湿地居群、以及青海湖以西的部分居群(序列由Genbank下载获得),总计22个居群189个样品。所有ND4-tRNALeu序列比对得到703个位点,定义了39种单倍型。以南疆沙蜥为外群构建的贝叶斯树以及MP法构建的无根树,都分为A、B两大组。其中A包括若尔盖湿地居群以及玛多居群(A1)、青海湖以西的居群和兴海居群(A2)、西藏沙蜥;B包括青海湖以南的居群和天祝居群(B1)、青海湖以东北的居群(B2)。单倍型网络图分别对应了系统发育树上的各支。按照系统发育结果分组进行分子变异分析,得到组间变异占88.63%,各组间差异显著(P=0.000)。种群遗传结构分析得到,A1和B2可能经历了近期的种群扩张,前者扩张时间约为0.105-0.189 Ma B.P.(million years before present),后者为0.057-0.102 Ma B.P.,可能与末次间冰期的气候变暖有关。A2和B1对应的两个地理单元都具有较强的种群遗传结构,较为稳定。 青海沙蜥种组A、B两大支之间遗传距离大,分化明显,分化大约发生在4.29-2.38 Ma B.P.,推测青藏运动的A幕运动后复杂的地形变化可能是它们产生分化的原因。B1和B2分化大约发生在1.73-0.96 Ma B.P.,这与湟水流域构造运动发生的时间相符。在早、中更新世时期,B1支内部各居群可能有交流,中更新世末共和盆地出现的抬升以及河流溯源改道等事件可能是引起这支内部多个单倍型丢失的原因。A1、A2支的分化可能与倒数第三次冰期降临之后气候变冷、阿尼玛卿山的大冰帽有关。 The viviparous group of genus Phrynocephalus is mainly distributed in the Qinghai –Tibetan Plateau, including P. forsythii、P. theobaldi、P. erythrurus、P. putjatia and P. vlangalii. These species are adapted well to the cold clime there, and the origin of this group was the result of a vicariance event associated with the uplifting of the Qinghai -Tibetan Plateau. Although many works have been done, there are still several questions about classification、phylogenetic relationships and the biogeography of this group. The phylogeographic pattern of the P. vlangalii complex on the upper reaches of the Yellow River and the P. v. hongyuanensis in Zoige Wetland were studied in this thesis. On the upper reaches of the Yellow River, P. vlangalii complex are distributed in Zoige Wetland and the southeast and northeast region of Kuku-noor Lake. Because of the forming of the wetland in Zoige, the habitats for sand lizards are divided into many discontinuous ones, and it is necessary to analyze genetic structure in these unique habitats. The phylogeographic patter among P. putjatia、populations of P. vlangalii in the southeast region of Kuku-noor Lake and populations of P. vlangalii in Zoige Wetland hasn’t been studied yet, and the complicated geological events of the Plateau may play an important role in the populations’ diversity and species forming there. So these populations were gathered as a complex, and phylogeographic analysis were used to clarify these doubts. According to the two topics above, this thesis has two parts of results as follows: 1. Three geographic units of P. vlangalii hongyuanensis in Zoige Wetland were defined, and they were Xiaman (XM)、Hongyuan (HY) and Maqu (MQ). 785bp fragments of the mtDNA ND4-tRNAleu were determined from 72 samples and nine haplotypes were identified. As a whole, the nucleotide diversity was low,but the haplotype diversity was high. Analysis of molecular variance (AMOVA) showed that the three units were distinctly different(P<0.01),and 62.61% of the total genetic diversity was attributable to variation among units. There were 3 haplotypes shared among XM and HY,and no geographic clustering was observed except MQ from the TCS network. The results from the mismatch distribution analysis and Fu’s Fs test implied that there might be a recent population expansion in the XM unit, and this may be the reason why XM had a high haplotype diversity but a low nucleotide diversity. We estimate that the MQ and XMb have lower diversities because of some very recent geographic events, such as the formation of the Yellow river’s upriver and the Zoige Wetland. Although they are distinctly different, not enough time has passed for them to have diverged a great genetic distance. 2. 189 samples in 22 populations of P. vlangalii complex were collected, including P. putjatia、populations of P. vlangalii in the southeast and northeast region of Kuku-noor Lake、 populations of P. vlangalii in Zoige Wetland and the data from Genbank. 703bp ND4-tRNALeu sequences identified 39 haplotypes. P. forsythii was selected as outgroup, and both the Bayesian tree and the MP unrooted tree were divided into two groups(A、B). A included populations in Zoige Wetland and Xinghai(A1)、populations in the west of Kuku-noor Lake(A2)、P. theobaldi, and B included populations in the southeast of Kuku-noor Lake and Tianzhu(B1)、populations in the northeast of Kuku-noor Lake(B2). The haplotype network agreed with these groups. AMOVA showed that these five groups were distinctly different(P<0.01), and 88.63% of the total genetic diversity was attributable to variation among groups. There might be recent population expansion in A1 and A2, which corresponded to the dry climate of the last interglacial period. The expansion times were 0.189-0.105 Ma B.P. and 0.102-0.057 Ma B.P., respectively. A2 and B1 had strong genetic structure. The large genetic distance between A and B showed that they had been separated from each other for a long time(about 4.29-2.38 Ma B.P.), and it corresponded to the A phase of Qingzang Movement. The diversity between B1 and B2 at 1.73-0.96 Ma B.P. may be caused by the geological event in Huangshui valley. In early Pleistocene, populations in B1 may have gene flow because of geographic linkage, and later the uplift of the Plateau and the change of river route there made a few haplotypes lost. A1 and A2 were divided into two parts by A’nyemaqen Mountains at 0.66-0.37 Ma B.P., which maybe corresponded to glaciations at about 0.7 Ma B.P.

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大熊猫(Ailuropoda melanoleuca)是我国特有的濒危野生动物之一,迁地保护已经成为大熊猫物种保护的一个重要方面。当前大熊猫圈养种群数量增长很快,但是其“多雄配一雌”的交配(配种方式),以及生产过程中记录遗失等原因,造成圈养种群普遍存在亲子关系不清、谱系混乱等问题。为了加强遗传管理,有必要进行亲子关系鉴定、完善谱系;还需要检测种群的基因多样性水平,并在此基础上提出相应的遗传管理建议。 本研究应用9个具有高度多态性的大熊猫微卫星标记,对来自成都大熊猫繁育研究基地2006和2007年度出生的17只大熊猫幼崽及其全部候选父母共37个样品做了基因型分析;然后应用最大似然法,判断幼崽的父-子关系。同时,还对来自卧龙大熊猫保护研究中心的31只大熊猫个体也做了基因分型。将两个种群的数据进行比较:1)等位基因多样性和杂合度水平;2)通过F统计法,分析两个种群的遗传分化水平;3)通过遗传距离法,对所有个体进行聚类分析。 研究结果表明: 1)在母子关系不清的情况下,9个微卫星标记联合的父亲鉴定排除概率E为0.940090;而在母子关系确实的条件下,E= 0.993933。由于本研究中所有后代的母亲都是清楚的,因此这9个微卫星位点能够有效用于圈养大熊猫的亲子鉴定。似然法分析也表明,本研究所获得的亲子鉴定结果置信度在95%以上。 2)2005年种源交换后,成都大熊猫的等位基因多样性和杂合度水平都略高于卧龙种群(但没有达到显著水平),两个种群间的遗传分化水平也有所降低。但是,与卧龙相比,成都种群面临较大的近交压力。 基于以上研究结果,我们建议:进一步加强种源交换和基因交流,把两个种群当作一个遗传单元(MU)来进行管理。 Giant panda (Ailuropoda melanoleuca) is one of the endangerd wildlife endemic to China, and the ex-situ breeding become more and more important for the conservation of this speices. Although the captive population is expanding rapidly, the uncertainty occurs because the paternities of cubs are not clear due to the breeding pattern of “multiple male to single female,”as well as the records lost, resulting in errors in the studbook. For this reason, the paternity of the cubs and the genetic diversity of the captive giant pandas should be tested carefully to get information for the genetic management in the future. 9 polymorphism microsatellite markers were used to do paternity assignment for the 17 cubs born in 2006 and 2007 from Chengdu Research Base for Giant Panda Breeding (CGB) based on the maximum-likelihood methods. A total of 37 individuals were sampled, including all the candidate dams and sires. These samples were also used for comparing with 31 individuals sampling from Wolong China Research and Conservation Center for the Giant Panda (WCG). The comparing indexes were: 1) Allelic diversity and heterozygosity; 2) Genetic differentiation based on F-statistic; 3) Cluster analysis based on genetic distance. The results show that: 1) If the mother is unkown, the combined exclusion probability using these 9 loci is 0.940090. If the mother is known then the exclusion probability is 0.993933. Since the dam-offspring relationship is known in captive populations, the results could resolve unknown paternities in the study. And the confidence level of the results is 95% based on the likelihood methods. 2) The allelic diversity and the heterozygosity of CGB were higher than WCG (n ot significant), and the genetic differentiation was reduced a little since the genetic exchange between two populations in 2005. However, the population of CGB will be threatening by inbreeding seriously than that of WCG. From above, we suggest to reiforce the genetic exchange and geneflow between CGB and WCG, and these two populations should be regarded as one genetic management unit (MU).

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为建立对中药穿龙薯蓣、黄山药和盾叶薯蓣分子鉴别的方法,我们首先研究薯蓣叶绿体psbA-trnH片段遗传多样性,探讨该片段用于中药穿龙薯蓣、黄山药和盾叶薯蓣种间分子鉴别和系统学研究中的意义。在对不同类群薯蓣种的叶绿体psbA-trnH基因间区进行PCR扩增并测序,获得了该区间的完整序列的基础上,将所得序列用软件MEGA3.0进行相关分析。穿龙薯蓣的psbA-trnH片段全长274bp,黄山药全长279bp,盾叶薯蓣植物个体内的叶绿体DNA则有两种psbA-trnH片段,长度分别为241bp和503bp。MEGA3.0软件分析,三种薯蓣种间psbA-trnH片段序列的遗传距离(p-distance)为0.00350-0.04545,各个薯蓣种内的不同类群该序列无差异。用UPGMA法根据psbA-trnH序列的遗传距离建立系统发生树,每个种不同产地的薯蓣很明确地聚在一起,和形态分类一致。所得结果显示psbA-trnH片段序列在所研究的三种薯蓣种内保守,在种间具有明显的较大差异,而三种薯蓣及薯蓣属的系统发生关系尚须进一步研究。 以穿龙薯蓣、黄山药和盾叶薯蓣的psbA-trnH片段序列分析结果为基础,我们根据三种薯蓣在该片段上的特征序列位点设计了用于识别三种薯蓣的寡核苷酸片段并作为PCR反应的引物,将三种薯蓣的特征标记引物与psbA-trnH片段引物配合使用建立了相互识别三种薯蓣的显性和共显性两种检测方式,辅以NaOH碱法快速提取薯蓣干燥根茎总DNA,为三种薯蓣药材相互间快速准确鉴别创造了条件。 To establish molecular method for identifying Chinese medicine Dioscorea nipponica/panthaica/zingiberensis, we firstly study the Genetic diversity of psbA-trnH of Dioscorea and discuss the value of the fragment to molecular identity and systematology to three Dioscorea species (Dioscorea nipponica/panthaica/zingiberensis). The psbA-trnH fragments of different species of Dioscorea are amplified and sequenced,analyzing by software MEGA3.0. The length of Dioscorea nipponica and panthaica are 274bp and 279bp; two psbA-trnH fragments exist in Dioscorea zingiberensis individual, length of the shorter fragment is 241bp and the longer is 503bp. The interspecific Genetic distance (p-distance) of the three species is 0.00350-0.04545, and no intraspecific diversity exists. According to the Genetic distance, phylogenetic tree is built by UPGMA Method, each species of different place gather obviously, which is same to the shape classification. Results show that the psbA-trnH fragment is highly conservative at intraspecific level and obvious diversity at interspecific level, however, phylogenetic study is necessary for the Dioscorea in the future. Based on analysis to psbA-trnH fragment of Dioscorea panthaica, nipponica and zingiberensis, according to the special point of the three Yam species, primers as marker are designed for distinguishing the three species. Cooperating with primer pair psbAf-trnHr, dominant and codominant way is established for discriminating them. Moreover, assisted with NaOH method to extract total DNA of Dry stenophora of Yam, rapid and correct identity to the three species can be done.

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本文以中国科学院成都生物研究所培育的同源四倍体水稻和二倍体水稻为材料,进行遗传差异及产量、品质性状的研究:1、以二倍体水稻为对照,研究了同源四倍体水稻在2004 年和2005 年的结实情况。结果同源四倍体的花粉育性、结实率均不同程度下降,尤其低代材料更是大幅度下降。F 检验表明,同源四倍体不同个体间的各产量性状均差异显著,说明其具有很大的遗传改良潜力。从1996 年到2005 年对部分同源四倍体水稻进行了连续选择改良,T 检验表明经过9 年的选择改良,其结实率显著提高。本文还对同源四倍体水稻各产量性状间的相关性进行了分析,结果结实率与花粉育性、穗着粒数、穗实粒数极显著相关;理论产量与花粉育性、有效穗数、穗着粒数、穗实粒数、结实率及千粒重极显著相关。i2、用(CT)n 微卫星标记和PCR-Acc Ι分子标记对40 份同源四倍体和14 份二倍体水稻Wx 基因进行研究。结果,(CT)n 微卫星标记检测,Wx 基因呈Wx1、Wx2 和Wx3 3 种多态性;PCR-Acc Ι 检测,Wx 基因表现为G-型和T-型。测定稻米直链淀粉含量(AC)、胶稠度(GC)和糊化温度(GT),并探讨其与Wx 基因的关系,结果,二倍体和同源四倍体水稻均存在:Wx 基因型相同,AC 差异较小,Wx 基因型不同时,AC 差异较大,Wx1 基因型品种AC 最高, Wx2 基因型品种AC 次之,Wx3 基因型品种AC 最低;基因型相同时,同源四倍体AC 低于二倍体;同源四倍体与对应二倍体间,Wx 基因型相同时,AC 差异很小;而Wx 基因型发生变异时,AC 差异很大。同时,进行相关性分析,结果二倍体和四倍体水稻均存在AC、GC 与Wx 基因密切相关;而GT 与Wx 基因相关不显著。综合分析,(CT)n微卫星标记与PCR-Acc Ι 分子标记检测的相关系数为0.842,呈极显著正相关,可以将其结合起来进行同源四倍体新品种的选育和改良。3、利用RAPD 技术,对同源四倍体和二倍体水稻的遗传差异进行分析。17条引物在同源四倍体中扩增出178 条带(PPB=81.5%),在二倍体中扩增出173条带(PPB=76.3%);同源四倍体和二倍体的Shannon 遗传多样性指数分别为0.4848 和0.4679,多态信息量分别为0.3301 和0.3216,遗传距离分别为0.3572和0.3460;同源四倍体与其对应二倍体间遗传距离为0.1914-0.4633,平均为0.2914。表明同源四倍体的遗传多样性高于二倍体,且同源四倍体与其二倍体之间存在较大的遗传差异,这些将为水稻品种改良和新品种选育提供科学依据。上述产量、品质性状及遗传差异分析的结果,不仅有利于加快同源四倍体水稻的遗传改良进程,而且为进一步研究、利用同源四倍体水稻奠定了初步基础。 AbstractStudy on genetic diversity, yield characters and quality traitsof autotetraploid and diploid riceLiu Yuhua (Botany)Directed by Associate Prof. Tu ShengbinIn this study, diploid and autotetraploid rice, which were cultivated in ChengduInstitute of Biology were analyzed in genetic diversity, yield characters and qualitytraits.In the study, 2 diploid and 29 autotetraploid rice(2n=4x=48) materials, including4 preliminary and 25 advanced generation, were investigated for yield characters.Compared with diploid check, the pollen fertility and seed set of autotetraploiddeclined dramatically, especially in preliminary generation. F-test indicated that therewere remarkable differences among different varieties, showing that autotetraploidmaterials had strong potential for improvement. From 1996 to 2005, someautotetraploid rice had been selected and improved. T-test showed that seed setincreased obviously. The relationships among yield characters of autotetraploid ricewere analyzed. Seed set was strongly correlated with pollen fertility, total grainnumber per panicle and productive grain number per panicle; theoretical yield wasstrongly correlated with pollen fertility, productive panicle number per plant, totalgrain number per panicle, productive grain number, seed set and 1000-grain weight.Wx genotypes of 40 autotetraploid rice and 14 diploid rice were tested by usingthe (CT)n microsatellite marker and a cleaved amplified polymorphic sequence(CAPS) molecular marker named PCR-Acc Ι. Three microsatellite alleles wereproduced, i.e. Wx1, Wx2 and Wx3 both in autotetraploid and in diploid rice.Comparatively, PCR- Acc Ι molecular marker produced two genotypes, G-type andT-type for both autotetraploid and diploid rice. In this study, amylose content (AC), gel of consistency (GC) and gelatinization temperature (GT) of rice grain weremeasured and their relationships with Wx alleles were analyzed. The results showedthat variation of AC between autotetraploid and diploid rice was small when they hadthe same Wx genotype. However, variation of AC turned to be large when the Wxgenotypes were different. Actually, AC met the maximum value in Wx1 varieties andWx2 varieties the middle and Wx3 varieties the minimum. And AC was lower inautotetraploid than in diploid. Correlation analysis was done in this experiment. ACand GC of rice grain were probably controlled by Wx gene or other gene whoselocation was strictly linked to Wx gene, while GT of rice was not. The correlationcoefficient between Wx genotypes which revealed by (CT)n microsatellite marker andPCR-Acc Ι molecular marker was 0.842 with significant level. That revealed aconsistent result between the two types of markers. So it was possible to utilize boththe two types of markers to select and promote germplasm of autotetraploid rice.RAPD molecular markers were used to analyze the genetic diversity betweendiploid and autotetraploid rice. 178 repeatable bands were detected through 17 RAPDprimers with percentage of polymorphic bands was 81.5% in autotetraploid rice while173 repeatable bands were detected with percentage of polymorphic bands was 76.3%in diploid rice. According to the measurement of Shannon index, polymorphicinformation content and genetic distance, genetic diversity of autotetraploid was on ahigher level, genetic variation between autotetraploid and diploid rice was relativelyhigh. All these contributed to the genetic selection and improvement in rice breeding.As mentioned above, the results are not only helpful to promote the process ofrice improvement, but also to confirm the basic for further study of autotetraploid rice.