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1.
赤狐华南亚种与东北亚种上毛髓质指数的比较研究   总被引:8,自引:1,他引:7  
唐福全  张伟 《四川动物》2006,25(4):725-729
选取赤狐华南亚种和东北亚种8个部位上毛,用测试格测定上毛的髓质指数。结果表明,赤狐华南亚种和东北亚种上毛髓质指数在同一亚种的不同部位及亚种间差异极显著(P〈0.01)。无论在总体平均值上,还是在不同亚种个体同一部位上,赤狐东北亚种上毛的髓质指数均大于华南亚种。两亚种躯干部上毛髓质指数的平均值均明显大于前肢。这种差异性表现为从前肢末端到动物体躯干部呈梯度递增,其递增梯度在两个亚种的个体中表现有同步变化的趋势。  相似文献   

2.
3.
中国西南横断山区的野生鸭茅资源   总被引:1,自引:0,他引:1  
中国西南横断山区广泛分布野生鸭茅资源,包括鸭茅亚种和喜马拉雅鸭茅亚种。二者的分布范围相近,但在形态及物候发育等方面存在明显差异,鸭茅亚种的主要农艺性状优于喜马拉雅鸭茅亚种。两个亚种在人工控制条件下可以杂交形成三倍体后代,但自然状态下尚未发现二者杂交的确切证据。近年来,中国加强了对两个鸭茅亚种的基础研究,但从保护和利用研究角度出发,开展的工作较少。从来源角度分析,喜马拉雅鸭茅亚种为当地起源类型,鸭茅亚种为外来归化种的可能性较大。由于喜马拉雅鸭茅面临鸭茅亚种的竞争威胁,因此应加强中国喜马拉雅鸭茅亚种野生资源的保护和开发利用研究。  相似文献   

4.
Genetic polymorphism in the Far-Eastern leopard subspecies Panthera pardus orientalis was examined by RAPD-PCR analysis of total cellular DNA. Primers diagnostic for the leopard subspecies were detected. These primers can be used for differentiating wild-living animals from those kept in captivity and distinguishing different breeding lines. Genetic diversity was shown to be lower in animals from the zoo (D = 0.058) and higher in a natural population (D = 0.137). Two lines of the Persian subspecies were genetically closest (D = 0.042), and the Persian and Far-Eastern subspecies represented by wild animals, genetically most remote (D = 0.274). The level of genetic divergence of the Persian subspecies and Far-Eastern subspecies (zoo animals) was lower (D = 0.108) than between representatives of the Persian subspecies from the captive and natural population (D = 0.220). On the basis of analysis of relatedness, performed using NTSYS and PHYLIP software packages, the possibility cannot be excluded that some P. p. orientalis animals from the zoo have a hybrid origin and may be assigned to another Far-Eastern subspecies.  相似文献   

5.
Phylogenetic relationships among cultivated landraces and natural populations of wild subspecies of Tartary buckwheat were investigated at the individual level by constructing a phylogenetic tree based on amplified fragment length polymorphism (AFLP) markers. Seven individuals from seven cultivated landraces and 35 individuals from 21 natural populations of wild subspecies were utilized for AFLP analyses. Three groups were recognized: (1) all cultivated landraces and wild subspecies from northern Pakistan, central and eastern Tibet, and northwestern Yunnan, (2) wild subspecies from central and southern Sichuan, (3) wild subspecies from northern Sichuan and eastern Tibet. It was concluded that cultivated Tartary buckwheat probably originated in eastern Tibet or northwestern Yunnan in China.  相似文献   

6.
《Genomics》2021,113(5):3152-3162
Species and subspecies within the Salmonella genus have been defined for public health purposes by biochemical properties; however, reference laboratories have increasingly adopted sequence-based, and especially whole genome sequence (WGS), methods for surveillance and routine identification. This leads to potential disparities in subspecies definitions, routine typing, and the ability to detect novel subspecies. A large-scale analysis of WGS data from the routine sequencing of clinical isolates was employed to define and characterise Salmonella subspecies population structure, demonstrating that the Salmonella species and subspecies were genetically distinct, including those previously identified through phylogenetic approaches, namely: S. enterica subspecies londinensis (VII), subspecies brasiliensis (VIII), subspecies hibernicus (IX) and subspecies essexiensis (X). The analysis also identified an additional novel subspecies, reptilium (XI). Further, these analyses indicated that S. enterica subspecies arizonae (IIIa) isolates were divergent from the other S. enterica subspecies, which clustered together and, on the basis of ANI analysis, subspecies IIIa was sufficiently distinct to be classified as a separate species, S. arizonae. Multiple phylogenetic and statistical approaches generated congruent results, suggesting that the proposed species and subspecies structure was sufficiently biologically robust for routine application. Biochemical analyses demonstrated that not all subspecies were distinguishable by these means and that biochemical approaches did not capture the genomic diversity of the genus. We recommend the adoption of standardised genomic definitions of species and subspecies and a genome sequence-based approach to routine typing for the identification and definition of novel subspecies.  相似文献   

7.
Hippophae rhamnoides ssp. sinensis occurs mainly in the arid regions of northwest China. The wood stands of this subspecies play an important role in maintaining the local ecosystems in these regions. In addition, the genetic characteristics are essential to understand the historical range changes of this subspecies and its morphological differentiation with other subspecies. In this study, we developed nine microsatellite loci for this subspecies for the first time. We used the combining biotin capture method to enrich AG/CT/AC/GT/CG/GTG/CCA microsatellites. Twenty-six microsatellites were isolated from the enriching library and nine of them were found to be polymorphic through screening 12 distantly distributed individuals. The number of alleles per locus ranged from three to twelve and expected heterozygosity from 0.2659 to 0.4767, respectively. We further performed cross-priming tests in another subspecies and two congeneric species. These firstly isolated loci will provide a useful tool to investigate the genetic structure of this subspecies and its morphological differentiation from the other subspecies.  相似文献   

8.
Populations of Reed Buntings Emberiza schoeniclus in the western Palearctic are classified in two major subspecies groups according to morphology: northern migratory schoeniclus and Mediterranean resident intermedia . Songs of the two groups differ mainly in complexity and syllable structure, with intermedia songs being more complex. We explored the possibilities of song as a subspecies isolating mechanism by testing if male schoeniclus Reed Buntings reacted differently to field playbacks of songs from their own subspecies group, from the foreign subspecies group and from a control species, the Yellowhammer Emberiza citrinella . We tested 30 different males, each with a different song belonging to one of the three categories: own, foreign and Yellowhammer. Unlike songs of the two subspecies groups, Yellowhammer song elicited no response. Differences between reactions to own and foreign subspecies group songs were not significant, even though differences in response type (singing vs approaching) suggested some degree of uncertainty in classification of foreign song. We conclude from these results that the subspecies may be only in the first stages of the isolation process.  相似文献   

9.
The taxonomic rank of subspecies remains highly contentious, largely because traditional subspecies boundaries have sometimes been contradicted by molecular phylogenetic data. The most complete meta-analysis to date, for instance, found that only 3% of traditional avian subspecies represented distinct phylogenetic lineages. However, the global generality of this phenomenon remains unclear due to this previous study's narrow geographic focus on continental Nearctic and Palearctic subspecies. Here, we present a new global analysis of avian subspecies and show that 36% of avian subspecies are, in fact, phylogenetically distinct. Among biogeographic realms we find significant differences in the proportion of subspecies that are phylogenetically distinct, with Nearctic/Palearctic subspecies showing significantly reduced levels of differentiation. Additionally, there are differences between island and continental subspecies, with continental subspecies significantly less likely to be genetically distinct. These results indicate that the overall level of congruence between taxonomic subspecies and molecular phylogenetic data is greater than previously thought. We suggest that the widespread impression that avian subspecies are not real arises from a predominance of studies focusing on continental subspecies in North America and Eurasia, regions which show unusually low levels of genetic differentiation. The broader picture is that avian subspecies often provide an effective short-cut for estimating patterns of intraspecific genetic diversity, thereby providing a useful tool for the study of evolutionary divergence and conservation.  相似文献   

10.
The low density lipoproteins (LDL) of human plasma consist of a series of discrete particle subspecies of distinct physicochemical, immunological, and hydrodynamic properties. Such structural differences are intimately linked to the metabolic heterogeneity of circulating LDL in vivo. The current studies were designed to evaluate and compare the interaction of discrete LDL subspecies from normolipidemic subjects with the LDL receptor. Plasma LDL of d 1.019-1.063 g/ml from healthy males were fractionated into 15 subspecies of defined physicochemical characteristics by isopycnic density gradient ultracentrifugation as described earlier (Chapman et al., J. Lipid Res. 1988. 29: 442-458). The major LDL subspecies, LDL-5 to LDL-10, exhibited an overall range in density from 1.0244 to 1.0435 g/ml; individual subspecies increased in density by increments of 0.027 (LDL-5), 0.026 (LDL-6), 0.030 (LDL-7), 0.031 (LDL-8), 0.035 (LDL-9), and 0.042 g/ml (LDL-10), respectively. Taken together, these subspecies accounted for approximately 70% of the total mass of LDL of d 1.019-1.063 g/ml; their cholesterol: protein ratios decreased from 1.70 to 1.12 and particle size from 275 to 260 A with increase in density. ApoB-100 was the unique protein component in subspecies 5-8, with trace amounts (less than 0.2% of apoLDL) of both apoA-I and apoE in subspecies 9 and 10. The interaction of individual LDL subspecies with the LDL receptor on cultured human U-937 monocyte-like cells was compared by determining receptor binding affinities at 4 degrees C. Scatchard analysis of specific binding curves demonstrated a single class of binding site for each subspecies. The lowest dissociation constants were displayed by LDL subspecies 6 (Kd 5.71 nM), 7 (Kd 5.24 nM) and 8 (Kd 4.67 nM), while subspecies 5, 9, and 10 displayed significantly higher Kd values (8.35, 7.20, and 6.87 nM, respectively). Competitive displacement studies at 4 degrees C, in which unlabeled subspecies from the same gradient series competed for binding with 125I-labeled LDL subspecies, confirmed the relative binding affinities of these subspecies. As the hydrophobic lipid core of LDL undergoes a thermotropic transition at approximately 37 degrees C, which may in turn influence the surface structure of the particle, internalization and degradation studies were performed at 37 degrees C. No effect of temperature was detectable; again, LDL subspecies at each extreme of the density distribution (LDL-5 and LDL-10) displayed significantly lower binding affinities for the LDL receptor than that from the peak region (LDL-7).(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

11.
小熊猫种内遗传及亚种分化研究(食肉目:浣熊科)   总被引:4,自引:0,他引:4  
到目前为止,多数学者认为小熊猫种内已分指名亚种A.f.fulgens和川西亚种A.f.styani。然而,由于其个体毛色变异较大,一些学者对其亚种分化问题提出质疑。本文采用DNA指纹方法,对小熊猫的种内遗传和亚种分化进行了研究。结果表明,川西亚种所有个体在分子量约为8.4kb处均有一条指名亚种不具有的共有谱带,指名亚种所有个体则在分子量约为1.8kb处具有另外一条川西亚种不具有的共有谱带,且这两条谱带可通过双亲遗传给子代,说明此共有谱带可分别作为区分小熊猫川西亚种和指名亚种的特征带。另外,种内的遗传分化研究表明,川西亚种基因组的多态性强于指名亚种,且川西亚种内各个体之间的遗传变异高于指各亚种,说明小熊猫种内已形成遗传分化。因此,笔者认为以上研究结果为基因水平上进一步证明小熊猫种内已产生遗传分化,并形成两独立亚种,目前的亚种地位成立。  相似文献   

12.
Subspecies is used to designate taxa below species but above geographical populations. What patterns of genomic variation are expected if taxa are designated as subspecies? In this study, we carry out such a survey on the mangrove tree Avicennia marina (Forssk.) Vierh. of the Indo-West Pacific coasts. This species has three subspecies, distinguished by morphological traits and geographical distribution. We collected samples from 16 populations (577 individuals) covering all three subspecies and sequenced 94 nuclear genes. We reveal comprehensive genetic divergence among subspecies, generally higher than among geographical populations within subspecies. The level of genetic diversity differs among the three subspecies, possibly hinting at a degree of separation among their gene pools. We observed that divergence varies from locus to locus across the genome. A small portion of the genome is most informative about subspecies delineation, whereas the rest is undifferentiated or slightly differentiated, hinting at uneven gene flow and incomplete isolation. The three subspecies likely split simultaneously with gene flow among lineages. This reticulate evolution results in some discordance between morphology and genetics in areas of population contact. In short, A. marina subspecies show species-like patterns in some respects and population-like patterns in others. We propose that the subspecies designated in A. marina are informative in predicting genetic divergences and useful in making conservation decisions.  相似文献   

13.
《Genomics》2020,112(1):371-378
The salmonellae are found in a wide range of animal hosts and many food products for human consumption. Most cases of human disease are caused by S. enterica subspecies I; however as opportunistic pathogens the other subspecies (II-VI) and S. bongori are capable of causing disease. Loci that were not consistently present in all of the species and subspecies were removed from a previously proposed core genome scheme (EBcgMLSTv2.0), the removal of these 252 loci resulted in a core genus scheme (SalmcgMLSTv1.0). SalmcgMLSTv1.0 clustered isolates from the same subspecies more rapidly and more accurately grouped isolates from different subspecies when compared with EBcgMLSTv2.0. All loci within the EBcgMLSTv2.0 scheme were present in over 98% of S. enterica subspecies I isolates and should, therefore, continue to be used for subspecies I analyses, while the SalmcgMLSTv1.0 scheme is more appropriate for cross genus investigations.  相似文献   

14.
Populations of the flounder, Platichthys flesus , were screened for electrophoretically detectable protein variation at up to 37 loci. Atlantic and North Sea populations (subspecies flesus ) were genetically very similar to one another ( I >0.99) but different from Adriatic (subspecies italicus ) and Black Sea (subspecies luscus ) populations. The values for genetic identity between subspecies were around 0.9. Diagnostic loci enabled specimens of flesus, italicus and luscus to be differentiated from one another. Samples of flesus showed two to three times the heterozygosity levels of italicus or luscus , consistent with the greater population size of flesus . Morphological comparisons enabled populations to be categorized to subspecies. Platichthys flesus italicus and luscus are valid subspecies: the terms are not synonyms. The genetic distance data provide an estimate of divergence time of the three subspecies at about 2 My ago, an estimate that seems reasonable in the light of present knowledge concerning the recent geological histories of the Mediterranean and Black Sea basins.  相似文献   

15.
Delphinium variegatum is subdivided into three subspecies: D. v. variegatum is widespread in central and northern California, while D. v. kinkiense (an endangered taxon) and D. v. thornei are endemic to San Clemente Island off the coast of southern California. Electrophoretic data for 19 loci were collected from 7 populations of the mainland subspecies and all 24 known populations of the two insular endemic subspecies. Populations of the widespread mainland subspecies have more polymorphic loci (33.6% vs. 24.5%) and more alleles per polymorphic locus (2.61 vs. 2.15) than the insular endemic subspecies. However, observed heterozygosities are lower in the mainland subspecies (0.041 vs. 0.071), presumably due to lower levels of outcrossing (t = 0.464 vs. 0.895). Expected heterozygosities are similar (0.064 vs. 0.074) due to lower alternative allele frequencies in populations of the mainland subspecies (mean q = 0.075 vs. 0.190). Populations of the two insular subspecies are almost equivalent genetically (mean I = 0.997) regardless of taxonomic designation or geographic location. In contrast, one of the mainland populations is genetically well differentiated from the others. If this exceptional population is excluded, the mainland subspecies partitions genetic diversity similarly to the island subspecies, with most variation being found within populations (G(ST) = 0.073 vs. 0.030).  相似文献   

16.
A new subspecies, Kailasius autocrator murun Korb, ssp. n., of the species Kailasius autocrator (Avinov, 1913) from the eastern part of the Alai Mountain Ridge is described. This subspecies differs from the other known ones in the smaller size (the fore-wing length is less than 23 mm) and in the presence of 5 black rounded spots in the submarginal area of the hind-wing upper side (4 spots in the nominotypical subspecies and K. a. pshartanus). The new subspecies is shown to be the most archaic one among the subspecies of the genus Kailasius by the wing pattern. Possible ways for the origin of local and small populations of morphologically different subspecies of the genus are discussed.  相似文献   

17.
A new subspecies, Kailasius autocrator pshartanus, from the eastern Pamirs (the Muzkol Ridge, Sasyk River) is described. The new subspecies is distinguished from the nominative subspecies by the wing pattern and ecology. This subspecies has the most primitive wing pattern in the genus. The range of this species is considered to be the center of Kailasius genus origin.  相似文献   

18.
中国缓步动物门一新亚种及两新纪录种记述   总被引:9,自引:0,他引:9  
报道了我国缓步动物门1新亚种Diphascon(Adropion)scoticum qinlingensis subsp.nov.和中国2新纪录Rictersius coronifer ( Richters, 1903) (Eutardigrada, Macrobiotidae)和 Diphascon scoticum Murray, 1905 (Eutardigrada, Hypsibiidae).新亚种主要以爪的主枝基部极度收缩区别于世界其他产地的标本(指名亚种).新亚种和新纪录均采自秦岭山区.  相似文献   

19.
We examined population differentiation across a substantial portion of the range of the brown pelican (Pelecanus occidentalis) to assess (1) the genetic distinctness of the Galápagos subspecies (P. o. urinator) and (2) genetic differentiation between subspecies that inhabit the coasts of North and Central America (P. o. californicus and P. o. carolinensis). Birds were sampled from coastal California, coastal Florida, and the Galápagos Islands. Using a 957 bp (bp) fragment of the NADH dehydrogenase subunit 2 (ND2) gene, 661 bp of the mitochondrial control region, and eleven microsatellite loci we characterize population genetic differentiation among 158 brown pelicans. The Galápagos subspecies is genetically distinct from the sampled continental subspecies, possessing a unique ND2 haplotype and unique mitochondrial control region haplotypes. Samples from the two continental subspecies all possessed the same ND2 haplotype and shared four mitochondrial control region haplotypes. Bayesian clustering in STRUCTURE placed the Galápagos subspecies in a distinct genetic group with high probability, but could not differentiate the continental subspecies from one another. Estimates of migration rates from BayesAss indicated substantial migration between continental subspecies, but no migration between the Galápagos subspecies and either continental subspecies. There are clearly two Evolutionarily Significant Units within the range of the brown pelican, which warrants conservation attention. Further investigation should determine how the un-sampled subspecies (P. o. murphyi and P. o. occidentalis) fit into the broader picture.  相似文献   

20.
The numerical analysis of the phenotypical properties of Y. pestis strains, classified with 5 subspecies by 60 signs, was carried out. In comparing the properties of strains belonging to the main (nomenclature) subspecies with strains of other subspecies, the similarity index varied within the range 82-95%. A high degree of genetic affinity between 21 Y. pestis strains of five subspecies was demonstrated by the method of molecular DNA-DNA hybridization. The level of DNA homology with respect to the alpha-CTP.[3H] reference mark of Y. pestis P-1300 in strains belonging to different subspecies was found to be 84-97%. The plasmid spectrum of 25 examined strains of these three subspecies proved to be identical and consisted of plasmids similar in their electrophoretic motility to marker plasmids from Y. pestis strains EV from the Research Institute of Epidemiology and Hygiene and Otten.  相似文献   

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