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1.
Using 36 SSR markers and 889 accessions of common wild rice in China, the genetic diversity and the divergence among different geographical populations are investigated. Guangdong Province has the largest number of alleles, which account for 84% of the total alleles detected in the study, followed by Guangxi Province. The Nei's gene diversity indices, from high to low, are in the sequence of Hainan, Guangdong, Guangxi, Fujian, Hunan, Jiangxi, and Yunnan provinces. Two genetic diversity centers of Chinese common wild rice are detected on the basis of geographic analysis, i.e., the region covering Boluo, Zijin, Lufeng, Haifeng, Huidong and Huiyang counties of Guangdong Province and the region covering Yongning, Longan, Laibin and Guigang counties of Guangxi Province. The common wild rice in Yunnan, Hunan, Jiangxi, and Fujian provinces are diverged into respectively independent populations with relatively large genetic distances, whereas, those in Hainan, Guangdong and Guangxi provinces have relatively low genetic divergence. Under the condition of geographic separation, natural selection is considered as one of the primary forces contributing to the divergence of common wild rice in China.  相似文献   

2.
Microsatellite genotyping and amplified fragment length polymorphism (AFLP) techniques are often utilized in studies of conservation genetics of endangered animals. To select a more effective marker system for conserving the endangered forest musk deer, we used microsatellite and AFLP markers to estimate levels of genetic diversity of two populations, the pure mother Jinfengshan (JFS) group and the offspring Baisha (BS) group with introduction of new blood. It was expected that JFS would pos- sess significa...  相似文献   

3.
1MATERIALS AND METHODS1.1PLANT MATERIALS FROM AUGUST TO SEPTEMBER IN2004,WE TRAVELED EX-TENSIVELY IN HEILONGJIANG PROVINCE LOOKING FOR THE WILD LOTUS.THE WILD LOTUS WAS FOUND AT40LOCALITIES AND49ACCESSIONS OF SAMPLES WERE COLLECTED AT THESE LOCALITIES(FIG…  相似文献   

4.
Public concern is often expressed at cultivars because the domestication and modern plant breeding have led to a reduction in the genetic diversity of crops and loss of genes, which could result in crops' genetic vulnerability to changes in the spectrum of pestssity of varieties in this zone is very important to the whole rice production in China. REZV, a important japonica rice production areas with more than 278 thousands ha rice which was about 71% of rice area in north China, accounted fo…  相似文献   

5.
Ligularia Cass., (Compositae) is a highly diversified genus, and more than 100 species of which are distributed in the eastern Qinghai-Tibet Plateau and adjacent areas. Ligularia species have been studied with respect to secondary metabolites, and many sesquiterpenes of the furanoeremophilane type have been isolated from them. In order to find correlates among these variations, and ultimately understand the diversity-generating mechanism of Ligularia species in the Hengduan Mountains, we initiated an extensive study that uses furanoeremophilanes as a chemical index and the DNA sequence as a genetic index. Furanoeremophilanes have been detected conventionally by Ehrlich's test, which has been used in a search for novel natural products. As for the DNA sequence, we determined the nucleotide sequence of the atpB-rbcL intergenic region in the present study.  相似文献   

6.
Sika deer (Cervus nippon) is a cervid endemic to mainland and insular Asia and endangered. We analyzed variation in the mitochondrial DNA (mtDNA) control region for four subspecies to understand the genetic diversity, population structure and evolutionary history in China. 335 bp were sequenced and eight haplotypes were identified based on 25 variable sites among the populations. Sika deer in China showed lower genetic diversity, sug- gesting a small effective population size due to habitat fragmentation, a low number of founder individuals, or the narrow breeding program. AMOVA analysis indicated that there was significant genetic subdivision among the four populations, but no correlation between the genetic and geographic distance. PhyIogenetic analyses also revealed that Chinese sika deer may be divided into three genetic clades, but the genetic structure among Chinese populations was inconsistent with subspecies designations and present geographic distribution. Including the sequence data of Japanese sika deer, the results indicated that Chinese populations were more closely related to Southern Japanese populations than to the Northern Japanese one, and the Taiwan population was closer to populations of Northeastern China and Sichuan than to those of Southern China.  相似文献   

7.
The shape and color of rice leaves are impor- tant agronomic traits that directly influence the proportion of sunlight energy utilization and ultimately affect the yield and quality. A new mutant exhibiting stable inheritance was identified as derived from ethyl methane sulfonate (EMS)-treated restorer Jinhui 10, tentatively named as narrow and striped leaf 1 (nsll). The nsll displayed pale white leaves at the seeding stage and then white striped leaves in parallel to the main vein at the jointing stage. Meanwhile, its leaf blades are significantly narrower than the control group of Jinhui 10. The chloroplast structures of cells in the white striped area of the nsll mutant break down, and the photosynthetic pigments are significantly lower than that of the wild type. Moreover, fluorescence parameters, such as Fo, Fv/Fm, ФpsⅡ, qP, and ETR, in the nsll mutant are significantly lower than those of the wild type, and the photosynthetic efficiency is also significantly decreased. These changes in leaf color and shape, together with physiological changes in the nsll, result in smaller plant height and a decrease in the most important agro- nomic traits, such as the number of grains per panicle, grain weight, etc. Genetic analysis shows that the narrow and striped traits of the nsll mutant are controlled by a single recessive nuclear gene, which is located between InDel 16 and InDel 12 in chromosome 3. The physical distance is 204 kb. So far, no similar genes of such leaf color and shape in this area have been reported, This study has laid asolid foundation for the gene cloning and function analysis of NSL 1.  相似文献   

8.
The hydrothermal synthesis and crystal structures of four coordination polymers, namely, 2D [Zn(μ3-ta)(pytaH)]n (1), 2D [Zn(μ3-pyta)Cl]n (2), 1D [Cd(μ-pyta)2(H2O)]n (3), and 3D [Cd(μ3-pyta)(μ-Cl)]n (4) (pyta = (4-pyridylthio)acetate, ta = thioglycolate), are reported. They are based on (4-pyridylthio)acetate and its derived ligand. The ta^2- ligand present in 1 was generated from an in situ C(sp^2)-S bond cleavage of the pyta ligand. In these compounds, versatile intermolecular interactions, such as close S…S interactions and strong (O-H…O/N/S) or weak (C-H…O/S, C-H…Cl) hydrogen bonding interactions, play an important role in the formation of three-dimensional supramolecular networks in the solid state.  相似文献   

9.
The pedigrees of three sequenced rice cultivars were analyzed to show that a majority of the genetic composition of 'Nipponbare' originates from japonica cultivars while the minority originates from indica cultivars. In contrast, '93-11' is derived mainly from indica cultivars with a smaller contribution from japonica cultivars. All ancestors of 'Guang lu ai 4' appeared to be indica lines. A set of molecular markers (46 InDels and 53 SSRs) polymorphic between 'Nipponbare' and '93-11' were examined in 46 typical indica and 47 typical japonica cultivars selected from 443 accessions according to Cheng's index. All cultivars were divided into indica and japonica groups without overlapping when clustered by Cheng's index, InDels and SSRs. Much higher InDel and SSR diversity between groups than within groups implies that the marker polymorphisms between 'Nipponbare' and '93-11' represent a large proportion of inter-subspecific diversity. About 85% of indica cultivars and more than 90% of japonica cultivars were confirmed to have the same PCR banding patterns as '93-11' and 'Nipponbare', respectively. Some polymorphic loci between 'Nipponbare' and '93-11' cannot be validated in other indica and japonica cultivars, either as subspecies-specific but not predominant alleles, or alleles not specific between the two groups. It was concluded that molecular markers developed from sequence polymorphism between 'Nipponbare' and '93-11' often represent inter-subspecific diversity, although some exceptions were sensitive to either particular marker loci or particular cultivars.  相似文献   

10.
Phylogenetic and taxonomic studies on ciliate protists using molecular approaches have been demonstrated to be very reliable to form strong conclusions and results. In the present work, species separation of some morphologically similar stichotrichous ciliates, two species of Pseudokeronopsis and two species of Apokeronopsis, was reexamined using amplified ribosomal DNA restriction analysis (PCRRFLP). Five of 10 restriction enzymes revealed species-specific polymorphic patterns, of which four similar stichotrichs could be significantly separated and identified. Among them, EcoR I offered almost no significantly different restriction fragment patterns, but the four species could be separated from one another and identified with Hae III. Distinctly different restriction digestion haplotypes and similarity indices separated the species, and were used to construct a phylogeny. Phylogenies based on ITS2 nucleotide sequences and ITS2 secondary structures supported the separation of Pseudokeronopsis and Apokeronopsis using RFLP analysis, although three Pseudokeronopsis carnea populations did not cluster together. In addition, phylogenetic analyses using multiple algorithms confirmed that these two genera formed two distinct groups within the urostylids.  相似文献   

11.
西北太平洋浮游有孔虫的SSU rDNA序列及其古海洋学意义   总被引:1,自引:0,他引:1  
研究对采集于西北太平洋冲绳海槽表层水体中的活浮游有孔虫进行DNA分析尝试,获得了西北太平洋浮游有孔虫Pulleniatina obliquiloculata 和Globigerina sp.等的SSU rDNA序列特征,并与南太平洋地区属种的DNA序列进行对比. 结果显示两不同海区P.obliquiloculata个体的SSU rDNA差异与同一个体内不同拷贝序列间差异类似,仅为0.7%—1.2%. 详细比较研究认为,传统微体古生物形态学定义种对西北太平洋与南太平洋的P.obliquiloculata来说具有可靠的分子生物学证据.  相似文献   

12.
通过制备野生鼠尾藻基因组DNA,用同源克隆技术获得鼠尾藻的SSU rDNA序列。该序列长度为1 784 bp,A、G、T、C 4种碱基的含量分别为24.66%、27.75%、26.35%和21.24%,序列已提交至GenBank,登录号为JN604979。选用GenBank数据库中已有的褐藻SSU rDNA序列构建系统发生树,结果显示:鼠尾藻与半叶马尾藻,铜藻以及Sargassum macrocarpum聚为一支,并且与半叶马尾藻的亲缘关系最近。  相似文献   

13.
把研究真核细胞表达基因种类和水平的基因标签串测序法引入环境细菌遗传多样性分析,选择细菌6S核糖体RNA基因(rDNA)内026碱基对高变异区段为该基因变异类型的标签,连接成标答中并测序,用标签类型、频率和2多样性指数等参数在分子水平上分析环境细菌遗传多样性,建立了环境细菌遗传多样性分析的基因标签串测序法,该方法在分析环境隐含遗传多样性、提示污染生物学效应和评价环境质量等方面有的应用价值。因使用共同  相似文献   

14.
    
Living planktonic foraminifera(PF)samples from the Okinawa Trough of the northwestern Pacific Ocean were taken for DNA analysis.The SSU rDNA sequences of two PF species,Globigerina sp.and Pulleniatina obliquiloculata collected at Station WP01,were obtained and compared with those from the southwestern Pacific Ocean.Only small differences(<0.7%—1.2% for P. obliquiloculata,and 0.3% for Globigerina sp.)were found between samples from the north-and south-western Pacific Ocean areas and this molecular evidence supported that these micropaleontological species are the same species,which implies that the West Pacific Ocean circulation system influences the planktonic foraminiferal gene communication.  相似文献   

15.
    
Living planktonic foraminifera (PF) samples from the Okinawa Trough of the northwestern Pacific Ocean were taken for DNA analysis. The SSU rDNA sequences of two PF species, Globigerina sp. and Pulleniatina obliquiloculata collected at Station WP01, were obtained and compared with those from the southwestern Pacific Ocean. Only small differences (<0.7%—1.2% for P. obliquiloculata, and 0.3% for Globigerina sp.) were found between samples from the north- and south-western Pacific Ocean areas and this molecular evidence supported that these micropaleontological species are the same species, which implies that the West Pacific Ocean circulation system influences the planktonic foraminiferal gene communication.  相似文献   

16.
本研究旨在探索中国锦屏地下原始极深环境中极端微生物群落结构及功能。本研究采用高通量测序技术对锦屏极深环境中4个岩石样品和7个水样中存在的微生物群落进行了研究,共获得732 477条高质量序列(Clean tags),可聚类到1 318个有效OTUs,各样品菌群之间存在一定差异,但其优势菌门一致,为变形菌门(Proteobacteria)、放线菌门(Actinobacteria)、拟杆菌门(Bacteroidetes)和厚壁菌门(Firmicutes)。采用PICRUSt分析了样品菌群对应的基因功能,结果表明涉及碳水化合物代谢、氨基酸代谢、能量代谢、辅助因子和维生素代谢等基因功能的丰度最高。结果表明锦屏地下原始极深环境中微生物群落复杂,但主要菌群相对稳定。  相似文献   

17.
The genetic diversity of two natural populations (M, N) of Beijing duck (Anas platyrhynchos) and 11 artificially selected lines of Beijing duck (A, B, E-L, O) from China Gold Star Duck Production Ltd., along with two Cherry Valley duck lines (C and D) from the British Cherry Valley Livestock Division, was evaluated using 18 microsatellite markers covering 16 linkage groups. A phylogenetic tree of the 15 populations of duck, formed of four main branches, was constructed from Nei’s DA genetic distance. The mean genetic differentiation index (FST) in all loci, Nei’s standard genetic distance (Ds), and the genetic distance DA between the Beijing duck and the Cherry Valley duck were 0.075, 0.143 and 0.142, respectively. These results demonstrated a high degree of genetic similarity between the two breeds and supported the hypothesis that the Cherry Valley duck was derived from the Beijing duck. The FST matrix of seven clusters of Beijing duck suggested that the efficiency of selection was not significant to some extent and should be supplemented by marker-assisted selection.  相似文献   

18.
生物多样性是人们赖以生存和发展的物质基础,本文介绍了生物多样性的基本含义及保护生物多样性的重要性。  相似文献   

19.
冶勒自然保护区垂枝香柏的ISSR遗传多样性研究   总被引:1,自引:0,他引:1  
利用ISSR分子标记对冶勒自然保护区垂枝香柏(Sabina pingii(Cheng ex Ferré)的6个居群共65个个体进行了遗传多样性的比较分析. 10个引物共扩增出121个多态性位点,物种水平多态性位点百分率(PPB)为98.37%,居群水平的多态性位点百分率相对较低,在37.40%~51.22%间. 居群间遗传分化系数Gst为0.4959,即总遗传变异中有50.41%的变异发生在居群内,49.59%的变异发生在居群间,基因流Nm为0.5083. 居群间及居群内分化均较明显,可能是由于地理隔离  相似文献   

20.
为探讨首都医科大学长爪沙鼠群体的遗传状况,应用生化基因位点遗传检测方法,测定初始和生物净化长爪沙鼠群体27个生化位点等位基因的分布。结果表明,2个长爪沙鼠群体均具有丰富的遗传多样性;生物净化群体与初始群体比较有7.14%的基因丢失率,但尚未出现明显的遗传分化现象(FST<0.05);群体均偏离了哈迪-温伯格平衡(P<0.05)。  相似文献   

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