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1.
The present study was conducted to assess the genetic diversity, population structure, and relatedness in Indian red jungle fowl (RJF, Gallus gallus murgi) from northern India and three domestic chicken populations (gallus gallus domesticus), maintained at the institute farms, namely White Leghorn (WL), Aseel (AS) and Red Cornish (RC) using 25 microsatellite markers. All the markers were polymorphic, the number of alleles at each locus ranged from five (MCW0111) to forty-three (LEI0212) with an average number of 19 alleles per locus. Across all loci, the mean expected heterozygosity and polymorphic information content were 0.883 and 0.872, respectively. Population-specific alleles were found in each population. A UPGMA dendrogram based on shared allele distances clearly revealed two major clusters among the four populations; cluster I had genotypes from RJF and WL whereas cluster II had AS and RC genotypes. Furthermore, the estimation of population structure was performed to understand how genetic variation is partitioned within and among populations. The maximum ?K value was observed for K = 4 with four identified clusters. Furthermore, factorial analysis clearly showed four clustering; each cluster represented the four types of population used in the study. These results clearly, demonstrate the potential of microsatellite markers in elucidating the genetic diversity, relationships, and population structure analysis in RJF and domestic chicken populations.  相似文献   

2.
Starch gel electrophoresis was performed to study polymorphism of hordeins encoded by the Hrd A, Hrd B, and Hrd F loci in 366 local old barley accessions from Iran and Central Asian countries, including Turkmenistan, Uzbekistan, Tajikistan (Mountain Badahsan), and Kirgizia. In total, 60 alleles with frequencies of 0.0003–0.2818 were observed for the Hrd A locus, 106 alleles with frequencies of 0.0003–0.1603 were observed for the Hrd B locus, and five alleles with frequencies of 0.0164–0.4131 were observed for the Hrd F locus. The alleles and allele frequencies displayed irregular distributions in barley populations of the above countries. Cluster analysis of the matrix of allele frequencies in populations from known collection sites revealed a cluster structure of local barley populations within each country. Local populations formed five differently sized clusters in Iran, six in Turkmenistan, three in Uzbekistan, and three in Kirgizia. The variation and allele frequency distribution of the hordein-coding loci in Iran and Central Asian countries were assumed to result from the introduction and spreading of barley forms via migrations of husbandmen.  相似文献   

3.
For the first time in 1989 citrus bacterial canker disease has seen on Citrus aurantiifolia in southern Iran. A total of 43 strains from affected citrus trees, ten strains from South Korea and representative from all known five pathotypes of Xanthomonas axonopodis pathogenic on citrus trees were used in this study. Isolated strains from Iran were indistinguishable by phenotypic, FAMEs, and SDS-PAGE analyses but showed different host range. First group were pathogenic on all tested citrus seedlings including C. aurantiifolia, C. limettioides, C. limon, C. jambhiri, Poncirus trifoliata X C. paradisi, C. aurantium, C. paradise, C. medica, P. trifoliate, C. grandis, C. sinensis, C. reticulate and C. sinensis X P. trifoliate. Pathogenicity of the second group were limited to C. aurantiifolia, C. limettioides, C. limon, C. jambhiri, P. trifoliata X C. paradis, and C. aurantium. Among the strains studied by AFLP fingerprinting six clusters were found. These clusters were: (1) strains of pathotype C; (2) strains of pathotypes B and D; (3) strains of pathotype A together with the main group of the Iranian strains; (4) strains isolated from Korea; (5) strains of pathotype E; and (6) seven strains from Iran which made a completely separate cluster. Strains from pathotypes B and D could not be differentiated by AFLP. The tested Iranian strains belongs to the two different groups and strains from Korea grouped as a subcluster from main cluster of Iranian strains belong to the pathotype A.  相似文献   

4.
The West Asian stripe-necked terrapin Mauremys caspica is widespread throughout the Middle East—a region for which only few phylogeographic studies are available. Due to landscape alteration, pollution and intensification of water management, M. caspica is increasingly threatened. However, genetic diversity among and within populations is poorly known, impeding the identification of management units. Using a nearly rangewide sampling, we analyzed 14 microsatellite loci and mtDNA sequences in order to gain insight into the population structure and history of M. caspica. In agreement with a previous study, we found two clusters of mitochondrial haplotypes, with one cluster distributed in the east and the other in the west of the range. However, our microsatellite data suggested a more pronounced geographical structuring. When null alleles were coded as recessive with structure 2.3.2, three clusters were revealed, with one cluster matching roughly the range of the western mitochondrial cluster, and the composite ranges of the two other microsatellite clusters correspond to the distribution of the eastern mitochondrial cluster. Naïve structure analyses without correction for null alleles were congruent with respect to the two eastern microsatellite clusters, but subdivided the western cluster into two units, with an additional geographical divide corresponding to the ‘Anatolian diagonal’—a well-known high mountain barrier impeding exchange between western and eastern taxa. In naïve analyses, the westernmost microsatellite cluster (from Central Anatolia) is quite isolated from the others, and its distinctness is also supported by fixation indices resembling the values among the other three clusters. One of the two eastern clusters is distributed in the Caucasus region plus Iran, and terrapins from Saudi Arabia and Bahrain constitute the second eastern cluster, supporting the view that these endangered populations are native. Coalescent-based analyses of our microsatellite data reveal for all four clusters bottlenecks 4,000–20,000 years ago, suggesting that climatic fluctuations of the Late Pleistocene and Holocene played an important role in shaping current genetic diversity. We propose that each of the four identified clusters, including the Central Anatolian one, should be treated as a distinct management unit. The presence of non-native terrapins in the animal trade of Bahrain highlights the danger of genetic pollution of the endangered Arabian populations. Further sampling is needed to elucidate the situation in southern and central Iran and Iraq. Our results confirm that genetic data do not support the validity of any of the three morphologically defined subspecies of M. caspica, and we propose that their usage be abandoned.  相似文献   

5.
Microsatellite variations in Castanopsis species in Japan were examined to clarify the genetic relationships among 25 local populations according to the difference in the number of layers of adaxial epidermis in the leaves. Six microsatellite loci were assayed for 629 seedlings from the populations, and these seedlings were classified into five types according to the state of the leaf epidermis. Remarkable differences in the allele frequency of the six microsatellite loci were observed among these local populations. The coefficients of genetic differentiation, RST, of each locus ranged from 0.209 to 0.388. An unweighted pair-group method (UPGMA) phenogram constructed on the population pairwise RST over the loci revealed three clusters (A–C), and six sub-clusters. These clusters reflected the differences in the occurrence frequency of seedlings in each epidermis type within a population. Our findings suggest that clusters A and C are the local populations dominated by Castanopsis sieboldii and Castanopsis cuspidata, respectively, while local populations of cluster B are composed of the two Castanopsis species and/or include many individuals derived by hybridization. The six sub-clusters were found to reflect the geographic relationship among the populations, suggesting a different process for geographic population dynamics during the postglacial period.  相似文献   

6.
The genus Plantago is particularly interesting for evolutionary studies because of its wide range of mating systems. We have developed primers for five highly polymorphic microsatellite loci isolated from P. lanceolata. All five loci amplified and were polymorphic in the two populations examined, Lowsteads Beach in the United Kingdom and Duke in the United States. These new markers will allow a comparison of population structure between the outcrossing species P. lanceolata, and the highly selfing species P. major.  相似文献   

7.
Abstract

This study represents a preliminary step toward understanding the genetic structure of Persian oak in Iran. The genetic variability of Quercus brantii in Western forest of Iran was evaluated by amplified fragment length polymorphism (AFLP), chloroplast microsatellite and leaf morphology. Fifty-five trees from eight regions were sampled from across the range of Chaharmahal va Bakhtiari province of Iran. Twenty morphological traits were analyzed through clustering and ordination method. At morphological level, the applied statistics suggest that macromorphological traits significantly differentiate between populations. The overall sample shows a proportion of AFLP polymorphic markers of 92.1%, denoting a high level of variability. Based on AFLP data, differences among populations within geographic regions account for 11.6% of the total variation and only 0.57% is attributed to variation among regions. Based on chloroplast microsatellite (cpSSR), 34% of total variation was found among populations, suggesting a high within-population haplotype diversity. The dendrogram obtained from cpSSR showed a general pattern quite different from the pattern obtained from morphological analysis and AFLP markers.  相似文献   

8.
Inter simple sequence repeat (ISSR) markers were used to assess the genetic diversity of 23 populations of chamomile. Ten primers were applied, producing 193 polymorphic bands. The polymorphic bands were analysed using Simple Matching (SM) similarity index and UPGMA cluster analysis. The resulting dendrogram consisted of four major groups which were in accordance to the geographical regions from which the populations had originated. Populations from North-western (NW), South-Eastern (SE), Central (C) Iran and Europe tended to be classified separately into groups. The highest gene diversity was observed in populations from the Central regions of Iran (0.25). Principal coordinate analysis (PCoA) confirmed the results of cluster analysis, while morphological classification was not related to molecular results. The population from Hungary had the greatest yield of essential oil (0.88 gr/dw), whereas for Iranian ones the greatest and the lowest essential oil yields belonged to NW (Aza = 0.6 and Ard = 0.7) and C (Isf 4, Isf 5 and Isf 6 = 0.44) regions, respectively. The results of the present study could contribute to a better understanding and management of conservation and exploitation of the chamomile germplasm.  相似文献   

9.
Six dinucleotide, three trinucleotide and seven tetranucleotide microsatellite loci developed for the great tit Parus major are presented. Thirty individual birds were screened at each locus. Loci were polymorphic (four to 19 alleles per locus). These markers provide a system to study paternity, genetic diversity in natural populations, gene flow, dispersal and inbreeding.  相似文献   

10.
Most cashmere goats are found in northern China and Mongolia. They are regarded as precious resources for their production of high quality natural fibre for the textile industry. It was the first time that the genetic diversity and population structure of nine Chinese cashmere populations has been assessed using 14 ISAG/FAO microsatellite markers. In addition, two Iranian populations and one West African goat population were genotyped for comparison. Results indicated that the genetic diversity of Chinese cashmere goats was rich, but less than those of the Iranian goat populations. All pairwise FST values between the Chinese cashmere goat populations reached a highly significant level (P < 0.001), suggesting that they should all be considered as separate breeds. Finally, clustering analysis divided Chinese cashmere goats into at least two clusters, with the Tibetan Hegu goats alone in one cluster. An extensive admixture was detected among the Chinese goat breeds (except the Hegu), which have important implications for breeding management.  相似文献   

11.
Asian elephants (Elephas maximus) are an endangered species. Their future survival depends on intensive conservation and management, based on in‐depth knowledge of particular populations. Molecular genetic methods, especially microsatellite analysis through noninvasive sampling, provides an effective means of obtaining such information. The use of tri‐ and tetranucleotide microsatellite markers is advantageous in noninvasive sampling through dung analysis. Here we describe the isolation and characterization of five tri‐ and tetranucleotide markers in the Asian elephant. All five loci were found to be polymorphic in a sample of 20 Asian elephants from Sri Lanka.  相似文献   

12.
The Central Asian racerunner, Eremias velox, is a widely distributed lizard of the Eurasian lacertid genus Eremias. Nucleotide sequences of mitochondrial genes, cyt b and 12S rDNA from 13 geographically distant localities in Iran and Central Asia, were analysed. Phylogenetic analyses of the sequence data unambiguously recovered five major clades within the E. velox complex with a high level of genetic divergence, indicating long periods of isolation. The basal position of the Iranian clades in the phylogenetic trees suggests that the E. velox clade originated on the Iranian plateau in the Middle Miocene. According to our calibrations, the northern Iranian clade diverged first some 10–11 Ma and that the Central Asian lineages split from the northeastern Iranian lineage approximately 6 Ma, most likely as a result of uplifting of the Kopet‐Dagh Mountains in the northern margin of the Iranian plateau. Topology of the phylogenetic trees, combined with the degree of the genetic distances among the independent lineages recovered in this study, provide a solid foundation for a fundamental revision of the taxonomic status of the major clades within this species complex.  相似文献   

13.
草鱼EST-SSR标记及5个不同地域群体的遗传结构分析   总被引:2,自引:0,他引:2  
以草鱼(Ctenopharyngodon idella)脑、肌肉、肝等组织构建cDNA文库,经测序获得unigenes序列45 318个,从中筛选微卫星序列共5 556个,据此设计EST-SSR引物118对,其中19对引物能够扩增出带型清晰且多态性较高的谱带。用这19个EST-SSR标记研究3个长江水系群体(石首、监利和长沙)和2个珠江水系群体(清远和肇庆)草鱼的遗传结构。结果表明,5个群体的平均多态信息含量(PIC)为0.415 4~0.460 4,显示草鱼群体的遗传多样性偏低;平均观测杂合度(Ho)为0.415 8~0.501 3,平均期望杂合度为(He)0.450 6~0.502 8,其中,长沙群体平均期望杂合度最高,为0.502 8,监利群体的平均观察杂合度和平均期望杂合度均最低,分别为0.415 8和0.450 6,即长沙群体的遗传多样性最高,监利群体的遗传多样性最低;对数据进行F-检验,结果表明,群体间的遗传分化程度低。Hardy-Weinberg平衡的卡方检验结果表明,5个群体均一定程度上偏离了平衡;聚类分析显示长沙群体、石首群体与监利群体聚成一支;肇庆群体与清远群体聚成一支,这与草鱼群体的流域分布一致。  相似文献   

14.
Lycopodium fordii Bak. (Lycopodiaceae, Pteridophyta) is a gardening plant with a native, fragmentary distribution in Taiwan. In this study, we described the development of eleven microsatellite loci in L. fordii for genetic studies. These new markers were tested in 16 individuals of three populations. The number of alleles ranged from 1 to 5 and the expected heterozygosity from 0.41746 to 0.72222. Four of the nine polymorphic loci were significantly deviated from Hardy-Weinberg expectations due to the heterozygote deficiency. The microsatellite markers have also been proved as informative genetic markers for other 15 Lycopodium species.  相似文献   

15.
The redlegged earth mite (Halotydeus destructor) and the blue oat mite (Penthaleus major) are major pests of pastures and crops in southern Australia. Reproductive modes, migration rates and levels of differentiation between populations were investigated using allozyme electrophoresis. Collections were made throughout Victoria and a sample was also obtained from Western Australia. Three enzyme loci were polymorphic in H. destructor (Mdh-1, Mdh-2 and Idh). Genotype frequencies of these loci did not differ between phenotypic males and females, providing no evidence for haplodiploidy. Allele frequencies were in Hardy-Weinberg equilibrium, indicating that H. destructor is diploid and sexual. This was confirmed via crosses between males and females. Allele frequencies differed between Victorian sites, although F statistics indicated little differentiation over all loci. A sample from Western Australia did not differ in allele frequencies from the Victorian sites. Four polymorphic loci were found in P. major (Mdh-1, Mdh-2, Idh and Gpi). Only a few multilocus genotypes occurred in a sample, indicating that P. major is parthenogenic. No male P. major were found in this study. A number of colour morphs were also identified and a genetic association between genital plate colour and clonal type was found in one population of P. major. Two different body colour morphs were associated with different clonal types.  相似文献   

16.
Microsatellite analysis of Aegilops tauschii germplasm   总被引:8,自引:0,他引:8  
The highly polymorphic diploid grass Aegilops tauschii isthe D-genome donor to hexaploid wheat and represents a potential source for bread wheat improvement. In the present study microsatellite markers were used for germplasm analysis and estimation of the genetic relationship between 113 accessions of Ae. tauschii from the gene bank collection at IPK, Gatersleben. Eighteen microsatellite markers, developed from Triticum aestivum and Ae. tauschii sequences, were selected for the analysis. All microsatellite markers showed a high level of polymorphism. The number of alleles per microsatellite marker varied from 11 to 25 and a total of 338 alleles were detected. The number of alleles per locus in cultivated bread wheat germplasm had previously been found to be significantly lower. The highest levels of genetic diversity for microsatellite markers were found in accessions from the Caucasian countries (Georgia, Armenia and the Daghestan region of Russia) and the lowest in accessions from the Central Asian countries (Uzbekistan and Turkmenistan). Genetic dissimilarity values between accessions were used to produce a dendrogram of the relationships among the accessions. The result showed that all of the accessions could be distinguished and clustered into two large groups in accordance with their subspecies taxonomic classification. The pattern of clustering of the Ae. tauschii accessions is according to their geographic distribution. The data suggest that a relatively small number of microsatellites can be used to estimate genetic diversity in the germplasm of Ae. tauschii and confirm the good suitability of microsatellite markers for the analysis of germplasm collections. Received: 8 September 1999 / Accepted: 7 October 1999  相似文献   

17.
Domestication is an excellent model to study diversification and this evolutionary process can be different in perennial plants, such as fruit trees, compared to annual crops. Here, we inferred the history of wild apricot species divergence and of apricot domestication history across Eurasia, with a special focus on Central and Eastern Asia, based on microsatellite markers and approximate Bayesian computation. We significantly extended our previous sampling of apricots in Europe and Central Asia towards Eastern Asia, resulting in a total sample of 271 cultivated samples and 306 wild apricots across Eurasia, mainly Prunus armeniaca and Prunus sibirica, with some Prunus mume and Prunus mandshurica. We recovered wild Chinese species as genetically differentiated clusters, with P. sibirica being divided into two clusters, one possibly resulting from hybridization with P. armeniaca. Central Asia also appeared as a diversification centre of wild apricots. We further revealed at least three domestication events, without bottlenecks, that gave rise to European, Southern Central Asian and Chinese cultivated apricots, with ancient gene flow among them. The domestication event in China possibly resulted from ancient hybridization between wild populations from Central and Eastern Asia. We also detected extensive footprints of recent admixture in all groups of cultivated apricots. Our results thus show that apricot is an excellent model for studying speciation and domestication in long‐lived perennial fruit trees.  相似文献   

18.
In Iran, three species of Leishmania have been incriminated as the causative agents of human leishmaniasis, Leishmania (L.) major, Leishmania tropica, and Leishmania infantum.Rhombomis opimus have been incriminated as a principal reservoirs of the parasitic protozoan Leishmania major, the causative agent of rural zoonotic cutaneous leishmaniasis (ZCL) in Iran. Rodents captured and examined to find Leishmania species using conventional methods including direct impression smear and microscopic observation inoculation samples to Balb/c and culture in NNN medium. Also molecular method was employed to detect Leishmania in rodents by amplifying a region of the ribosomal RNA amplicon of Leishmania (ITS1-5.8S rRNA–ITS2) using Nested PCR. Leshmania species were specified by DNA sequences. 36 (38.3%) of R. opimus were Leishmania positive using at least one conventional methods. Many more ITS-rDNA fragments were amplified from R. opimus but only 65 out of 74 PCR products contained enough DNA for direct sequencing or readable sequences. The PCR assays detected in Iranian R. opimus not only Leishmania major in 59 (79.7%) rodents but also Leishmania turanica in 6 (8.1%) rodents, another parasite of the great gerbil. These parasites were found in Turkemen Sahara, North East of Iran, in a focus of rural (ZCL). L. major and L. turanica in R. opimus firmly identified from Turkemen Sahara. Nine rodents with Leishmania infections unidentified which some were unreadable sequences, these could be mixed infections of L. major, L. turanica, Leishmania gerbillisensu lato and Leishmania close to L. gerbilli or a related species reported in sandflies previously from this location. The haplotypes of L. major and L. turanica were found to be identical to that of isolates of L. major and L. turanica from Iran and in GenBank elsewhere. R. opimus is probably the key reservoir in this ZCL focus because of its abundance and its infection rates with both L. major and L. turanica.  相似文献   

19.
Iranian chicken genetic resources are characterized by a long history and a vast diversity. This study represents the first results from the selection and evaluation of five polymorphic microsatellite markers for the genetic assessment of five native chicken populations located in the northwestern (West Azerbaijan), northern (Mazandaran), central (Isfahan, Yazd), and southern (Fars) provinces of Iran. The number of alleles ranged from three to six per microsatellite locus. All populations were characterized by a high degree of genetic diversity, with the lowest heterozygosity found in the Isfahan population (62%) and the greatest in the populations from West Azerbaijan and Mazandaran (79%). The largest Nei’s unbiased genetic distance was found between the Isfahan and Fars populations (0.696) and the smallest between the Mazandaran and Yazd populations (0.097). The Isfahan population was found to be the most genetically distant among all populations studied. These results serve as an initial step in the plan for genetic characterization and conservation of Iranian native chickens.  相似文献   

20.
该研究利用基于全基因组限制性酶切位点简化基因组测序技术(RAD seq技术),开发濒危植物羊踯躅(Rhododendron molle G. Don)全基因组SSR标记,并对3个群体共63份羊踯躅材料进行验证鉴定,为进一步研究羊踯躅的遗传多样性和群体遗传结构以及保护利用提供技术支持。结果显示:(1)羊踯躅基因组测序获得原始数据7.653G bp,过滤后为7.513G bp;经组装发现,羊踯躅171.534 M bp的基因组分布在498 252 contigs中。(2)通过SSR检测,在11 961 SSR位点中获得了11 687对SSR分子标记,并且二核苷酸为基序的重复类型最丰富,达51.76%。(3)随机选取128对SSR标记在6个羊踯躅株系中进行PCR扩增,获得20对高多态性的SSR标记。(4)用所选的20对多态性SSR标记对3个群体共63份羊踯躅材料进行验证分析发现,这些多态性SSR标记位点的等位基因数为4~16个,期望杂合度(He)为0.489~0.908。 研究表明,羊踯躅的SSR丰度适中,且二核苷酸为羊踯躅中最丰富的重复序列,该实验进一步证明RAD seq技术是一种经济有效的基因测序方法,实验中开发的SSR引物将有助于进一步研究羊踯躅和其他近缘种的群体结构和多样性。  相似文献   

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