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1.
The genetic diversity, subdivision, and differentiation of nine populations of Norway spruce (Picea abies (L.) Karst.) in Ukrainian Carpathians were studied using electrophoretic analysis of variability of enzyme systems in 346 trees aged from 80 to 150 years. Based on electrophoretic fractionation of enzymes extracted from seed endosperms in vertical slabs of 7.5% polyacrylamide gel, 20 loci of nine enzyme systems (ADH, ACP, DIA, GDH, GOT, MDH, LAP, FDH, SOD) were identified, and 71 allele variant were revealed. Each tree was heterozygous on average in 15.8% of its genes. The populations were characterized by low subdivision (F ST = 0.017) and differentiation (D N = 0.005). The main contribution to heterogeneity of population genetic structure was made by loci Dia-3, Lap-1, and Sod-3. Clustering and multivariate analysis revealed no observed trends in geographical or altitudinal position of the populations.  相似文献   

2.
Korshikov II  Gorlova EM 《Genetika》2006,42(6):824-832
In order to analyze the genetic structure, subdivision and differentiation within and between two small isolated populations of the Crimea relict endemic, Pinus stankewiczii (Sukacz.) Fomin, electrophoretic analysis of the isozyme variation at nine enzymatic systems was carried out using 183 oldest trees. It was demonstrated that in populations of P. stankewiczii, 80% of the genes were in polymorphic state. Each tree was heterozygous at 19.1% loci, and at 21.6% loci in artificial 50-year-old plantation. The genetic structure of two populations was less differentiated (DN = 0.006), compared to their individual localities (DN = 0.008-0.009). Within-population subdivision of the diffusely dispersed populations was higher (FST-GST = 1.8-2.0%) than that of the populations themselves (0.8%).  相似文献   

3.
In order to analyze the genetic structure, subdivision and differentiation within and between two small isolated populations of the Crimea relict endemic, Pinus stankewiczii (Sukacz.) Fomin, electrophoretic analysis of the isozyme variation at nine enzymatic systems was carried out using 183 oldest trees. It was demonstrated that in populations of P. stankewiczii, 80% of the genes were in polymorphic state. Each tree was heterozygous at 19.1% loci, and at 21.6% loci in artificial 50-year-old plantation. The genetic structure of two populations was less differentiated (D N = 0.006), compared to their individual localities (D N = 0.008?0.009). Within-population subdivision of the diffusely dispersed populations was higher (F ST -G ST = 1.8–2.0%) than that of the populations themselves (0.8%).  相似文献   

4.
Korshikov II  Pirko NN  Pirko YV 《Genetika》2005,41(3):356-365
Using electrophoretic analysis of 11 enzyme systems, we studied the genetic structure and differentiation of eight natural populations of silver fir Abies alba Mill. in the Ukrainian Carpathians. Of 24 isozyme loci identified, 66.8% proved to be polymorphic. The mean numbers of alleles and genotypes per locus in the populations were respectively 3.1 and 4.5. Each A. alba tree was on average heterozygous at 15.9% of genes. In six populations, the genotypic distribution for all of the loci examined corresponded to Hardy-Weinberg proportions. The populations studied had low levels of subdivision (F(ST) = 0.018; GST = 0.019) and differentiation. Nei's genetic distances between the A. alba populations in the region ranged from 0.002 to 0.009, being on average 0.006.  相似文献   

5.
Fourteen enzyme systems were analysed in leaf parenchyma of nine native and introduced populations of teak. These enzyme systems were encoded by 20 putative loci of which 18 were polymorphic. Populations showed a general lack of heterozygosity (average FIS = 0.11). On average over the 18 polymorphic loci, the genetic differentiation among provenances varied according to the estimator: 0.09 for GST, 0.12 for FST and 0.19 for . The cluster analysis showed two main gene pools, the first consisted of the Indian provenances and the second of African, Indonesian and Thai provenances. Genetic distances among populations of the same group were similar, and lower than the genetic distances between populations from different groups. The factorial analysis on genotypes of seedlings also showed the same geographic differentiation into two major groups. The possible natural distribution of teak in Java is discussed.  相似文献   

6.
伞花木(Eurycorymbus caraleriei)为中国特有的第三纪孑遗单种属植物,雌雄异株。采用超薄平板微型聚丙烯酰胺等电聚焦电泳方法对其5个自然居群和1个人工迁地保护居群的等位酶变异进行了初步研究。对7个酶系统中14个位点的等位酶居群遗传多样性及遗传结构分析结果表明:伞花木具有较高水平的遗传多样性,其每位点平均等位基因数A=1.6,平均多态位点比率P=42.9%,平均预期遗传杂合度Hr=0.216;各居群的遗传多样性无显著性差异,但都表现为严重偏离Hardy-Weinberg平衡的杂合子过量;其遗传变异主要发生在居群内(93.1%),居群间分化较小(Gst=0.069),居群问遗传一致度较高(I=0.965~1.000)。推断这可能是由于其古老孑遗性、雌雄异株、混和传粉方式的生物学特性以及其长寿命的生活史等原因所导致;同时,居群间的较高基因流(Nm=3.128)也可能起到很大的作用。还使用UPGMA聚类方法推断了武汉植物园迁地保护的野外居群来源,在对迁地保护居群的评价中发现迁地保护居群仅保存了该物种基因型多样性的16%,在此基础上提出了今后进一步的保育策略。  相似文献   

7.
Corylus avellana L. (hazel) is a long-lived, monoecious and wind-pollinated shrub species, widespread all over Europe. In Germany, hazel is intensively traded and planted, and thus is of central interest from a nature conservancy point of view. To assess the within- and between-population differentiation of hazel, 20 natural populations (18 from Germany, one from Italy and one from Hungary) were investigated genetically. Seven isozyme systems comprising 11 gene loci were analysed in up to 100 samples (average 92.6) per population, amplified fragment length polymorphisms (AFLP) were analysed in up to 50 samples (average 47.4) and nine cpDNA-SSR markers were assessed in 20 samples per population. Results for overall isozyme variability with Na 2.46 alleles per locus, allelic diversity (Ne) 1.39, expected heterozygosity He 21 % and 79 % polymorphic loci were in accordance with the findings of previous studies. The respective values for AFLPs were lower, but both marker systems revealed the same level of about 3.5 % differentiation between populations. For cpSSR only the Italian sample showed within-population variation and the two haplotypes were completely differentiated from all other populations expressing a unique genetic structure with one single haplotype. Among the three marker systems AFLPs showed the best ability to differentiate between populations. While only one isozyme locus revealed significant differentiation, 41 AFLP loci showed highly significant differentiation between all populations, but 26 loci when only German populations were considered. Consequently geographic differentiation analyses focused mainly on molecular markers. Mantel tests showed significant correlations between genetic and geographic distance, but in the unweighted pair-group method with arithmetic mean analyses, adjacent populations did not always form clusters. While chloroplast markers were able to clearly distinguish only the Hungarian population, the nuclear markers revealed clear spatial genetic structures. The correlations between geographic and genetic distance was high for AFLPs. The correlograms illustrate this effect for all populations as well as for the German populations.  相似文献   

8.
Using electrophoretic analysis of 11 enzyme systems, we studied the genetic structure and differentiation of eight natural populations of silver fir Abies alba Mill. in the Ukrainian Carpathians. Of 24 isozyme loci identified, 66.8% proved to be polymorphic. The mean numbers of alleles and genotypes per locus in the populations were respectively 3.1 and 4.5. Each A. alba tree was on average heterozygous at 15.9% of genes. In six populations, the genotypic distribution for all of the loci examined corresponded to Hardy-Weinberg proportions. The populations studied had low levels of subdivision (F ST = 0.018; G ST = 0.019 ) and differentiation. Neis genetic distances between the A. alba populations in the region ranged from 0.002 to 0.009, being on average 0.006.Translated from Genetika, Vol. 41, No. 3, 2005, pp. 356–365.Original Russian Text Copyright © 2005 by Korshikov, N. Pirko, Ya. Pirko.  相似文献   

9.
The organization of genetic variation in Phlox drummondii was investigated using both allozyme electrophoresis and quantitative genetics. Variation at five polymorphic enzyme loci was characterized in nine populations, and variation in 16 morphological and life-history characters was examined using an analysis of full- and half-sibs in seven populations. Significant levels of genetic variation were found at enzyme loci and for metric characters. Significant heritabilities were observed for 15 of the 16 characters examined. Genetic differences among populations were revealed both by Nei's genetic distance and by phenotypic differences, summarized by discriminant analysis. Partitioning variance in allozyme frequencies among hierarchical levels of genetic organization indicated that 94% of this variance lay within populations, 4% between populations within varieties, and 2% between varieties. Partitioning phenotypic variance for metric characters indicated that 73% lay within populations, 24% lay between populations within varieties, and 3% lay between varieties. Thus, both electrophoretic and metric characters indicated that despite extensive genetic differentiation among populations, most of the evolutionary potential of the species lies within populations.  相似文献   

10.
The genetic structure, subdivision, and differentiation of six populations of tall junipers (Juniperus excelsa Bieb.) in the Crimean Mountains and one population in Lebanon were investigated using 18 polymorphic allozyme loci as genetic markers. A high level of genetic variability of J. excelsa was established at the northern and southern boundaries of their natural habitats. The mean values of the main indicators of genetic polymorphism were P99 = 1.000, A = 3.167, HE = 0.370, and HO = 0.405. The subdivision and differentiation of populations were low (FST = 0.032, DN = 0.026), indicating the similarity of their gene pools.  相似文献   

11.
伞花木(Eurycorymbuscaraleriei)为中国特有的第三纪孑遗单种属植物,雌雄异株。采用超薄平板微型聚丙烯酰胺等电聚焦电泳方法对其5个自然居群和1个人工迁地保护居群的等位酶变异进行了初步研究。对7个酶系统中14个位点的等位酶居群遗传多样性及遗传结构分析结果表明:伞花木具有较高水平的遗传多样性,其每位点平均等位基因数A=1.6,平均多态位点比率P=42.9%,平均预期遗传杂合度He=0.216;各居群的遗传多样性无显著性差异,但都表现为严重偏离Hardy-Weinberg平衡的杂合子过量;其遗传变异主要发生在居群内(93.1%),居群间分化较小(Gst=0.069),居群间遗传一致度较高(I=0.965~1.000)。推断这可能是由于其古老孑遗性、雌雄异株、混和传粉方式的生物学特性以及其长寿命的生活史等原因所导致;同时,居群间的较高基因流(Nm=3.128)也可能起到很大的作用。还使用UPGMA聚类方法推断了武汉植物园迁地保护的野外居群来源,在对迁地保护居群的评价中发现迁地保护居群仅保存了该物种基因型多样性的16%,在此基础上提出了今后进一步的保育策略。  相似文献   

12.
Starch gel electrophoretic studies of 16 enzymes encoded by 34 Loci were performed on six brown trout populations. One new polymorphism is described at the Pmi-2 locus. Breeding data were analysed for both single and joint segregation of six loci: Aat-1, Cpk-1, G3p-2, Mdh-2, Mdh-3, and Pmi-2. All the loci are shown to segregate in simple mendelian ratios and one nonrandom joint segregation was observed. The polymorphism level, heterozygosities, and genetic distances were estimated and compared with those reported in other studies on brown trout and closely related salmonid species. The polymorphism level (25%) and average heterozygosity (9%) were high. Significant genetic distances were observed, but the average degree of differentiation between populations appeared to be small (9% of the total heterozygosity).  相似文献   

13.
中国石榴栽培群体遗传多样性的荧光AFLP分析   总被引:5,自引:0,他引:5  
苑兆和  尹燕雷  曲健禄  朱丽琴  李云 《遗传学报》2007,34(12):1061-1071
以中国山东、安徽、陕西、河南、云南和新疆6个栽培石榴群体的85个品种类型为试材,利用荧光标记AFLP对中国石榴群体遗传多样性进行了研究。结果表明:8对引物组合在种级水平扩增的多态性位点数范围从135~185个不等,平均为158.25个,多态位点百分比范围为62.5%~86.11%,平均为73.26%,说明中国石榴品种遗传多样性较为丰富;石榴品种种级水平遗传多样性大于群体水平,6个群体的遗传多样性依次为河南群体〉新疆群体〉陕西群体〉安徽群体〉山东群体〉云南群体,并且具有显著性差异;群体间的遗传分化系数GST为0.2018,说明石榴遗传变异主要存在群体内,群体间的遗传变异占总变异的20.18%,根据基因分化系数,测得的基因流Nm为1.9027,说明中国石榴群体间存在适当的基因交流;UPGMA聚类分析结果表明,同一群体的大部分品种都聚在一起,但同时存在部分基因交流。所有遗传参数表明,中国石榴栽培品种遗传多样性较为丰富,其中河南群体遗传多样性显著高于其他群体,在中国石榴品种选育中具有更为广阔的应用前景。  相似文献   

14.
Local germplasm of onion (Allium cepa L.) in West Africa is threatened by extinction. Sixteen populations of onion collected in five countries in West Africa were investigated for isozyme polymorphism using four polymorphic enzyme systems (ADH, MDH, 6-PGDH and PGI) among nine enzyme systems assayed. This is the first report on the genetic diversity of local landraces of onion. The inheritance of two dimeric enzyme systems PGI and MDH was demonstrated using F2 progeny arrays. The PGI system revealed a single locus with three alleles, and the MDH system revealed three loci with four alleles. Four polymorphic systems revealed nine alleles (adh-a1 and a2, mdh-c1 and c2, 6-pgdh-a1 and a2, and pgi-a1, a2 and a3) in the 16 local populations observed. The mean number of alleles per polymorphic locus was 2.25, and 67% of the alleles were present in all populations. Allele 6-pgdh-a2 was present in only two landraces (from Niger and Nigeria); it is considered to be a rare allele (frequency approximately 2%). Among the 16 populations, within-population diversity was greater (90%) than between-population diversity (10%). Genetic distance analyses showed an aggregate of all populations except for two, which originated from Nigeria, an English-speaking country. Received: 24 August 1995 / Accepted: 26 February 2001  相似文献   

15.
The genetic structure of Dolly Varden (Salvelinus malma Walbaum) populations from six rivers of southeastern Sakhalin and six rivers of the Kuril Islands was examined using electrophoretic, analysis of 22 enzyme systems encoded by 45 loci. In all populations, mean heterozygosities (0.044-0.105), mean numbers of alleles per locus (1.15-1.52), and proportions of polymorphic loci (18.2-39.4%) were estimated for all loci that had clear resolution. Highly significant heterogeneity of allele frequencies was detected among populations of both Sakhalin and the Kuril islands. By means of cluster analysis and multidimentional scaling, all populations were divided into the Sakhalin and Kuril groups. Within the groups, no association of genetic similarity with geographic distance between populations was observed. Although the average genetic diversity was similar in these regions, the relative interpopulation diversity was almost three times higher in the Kuril (17.6%) than in the Sakhalin (6.5%) groups. In all, the proportion of genetic diversity between regions (8.4%) was somewhat lower than the proportion of mean interpopulation diversity (11.3%). In small populations isolated from the sea, genetic variation was lower than in nonisolated populations. Allozyme differences between the northern and the southern forms of Dolly Varden are discussed.  相似文献   

16.
In order to determine genetic diversity ofOryza meyeriana (Zoll. et Mor. ex Steud.) Baill., 12 enzyme systems encoded by 17 loci were electrophoretically analyzed in 164 individuals of seven populations from Simao Prefecture, Yunnan Province, China. In comparison with those seed plants with the same life history and breeding systems, as well as the other species in the genusOryza, the species shows rather low levels of genetic diversity (A = 1.1,P = 8.0 %, Ho = 0.004 and He = 0.015) within populations and high genetic differentiation among populations. Fst was up to 0. 649, suggesting that 64. 9% of total genetic variability exists among populations. Considering high genetic differentiation among populations from a limited geographic region, most of the populations of the species are worth being protected, and therefore, great natural protection regions should theoretically be established in which a great deal of populations should be involved for developingin situ conservation management. Meanwhile, some priory localities forin situ conservation ofO. meyerzana in Yunnan Province, were proposed.  相似文献   

17.
Isoenzyme analysis of 5 populations of Chamaenerion angustifolium (L.) Scop. from different habitats revealed that only two of the nine enzymes scored were polymorphic. The estimated number of polymorphic loci was 2 out of 16. The only significant difference found was with regard to the gene and genotype frequencies of glucose-6-phosphate dehydrogenase (G6PDH). This difference could be demonstrated for established populations, occurring on contrasting soils but not for their seed populations.The genetic similarity between seed populations even in a sample obtained from only four established individuals was striking and its consequences for the life strategy and colonizing ability of the species are discussed. Genotypic differentiation due to age structure was not present. Genotype-dependent selection occurs in the seedling phase only.  相似文献   

18.
应用同工酶分析方法,测定北京市东灵山区两个分别代表干旱和湿润生境的辽东栋(QuercusliaotungensisKoiz.)群体的遗传结构。共分析统计了13 个酶系统30 个位点。结果表明:辽东栎群体内部存在丰富的遗传变异(多态位点百分率为86.6% ,等位基因平均数为2.25)。两群体遗传结构的相似性程度很高(D= 0.029, GST= 0.048);但在个别位点上仍存在较大差异,这些差异的产生可能与对小生境的适应有关。对不同年龄段的初步分析结果显示,基因频率的动态变化可能有其适应意义  相似文献   

19.
Dangasuk OG  Gudu S 《Hereditas》2000,133(2):133-145
The objectives of this study were (1) to investigate the genetic variability; and (2) to determine the phylogenetic relationship in the leguminous tree Faidherbia albida through out its range of distribution in East, West and Southern Africa. A total of 16 populations were subjected to enzyme electrophoresis and 6 enzyme systems (Adh, Mdh, G6pdh, Idh, 6Pgdh, and alpha-Est) encoded by 12 loci were scored. A total of fifty one different alleles were detected, with an average of 2.5 alleles per locus. Forty three percent of the loci were polymorphic at a 95% criterion. The average expected heterozygosity (gene diversity index H(e)) was 0.141. All provenances showed significant deviation from Hardy-Weinberg expectation. The UPGMA cluster analysis, based on Modified Rogers distance revealed close similarities between Eastern and Southern African provenances, except Debre zeit from Ethiopia, which was closest to West African populations than to the East African populations. Also, Bignona from West Africa was peculiarly closer to East African provenances. Differentiation of West African populations from Eastern and Southern African provenances was quite evident, emphasising the clinical pattern of variation in these two major geographical races of F. albida in Africa. Wright's F-statistics showed an overall significant deficit of heterozygotes, a common feature in mixed mating, entomophilous, widespread species such as F. albida. The dendrogram analysis showed wide separation among the three Ethiopian provenances indicating a high level of genetic differentiation and diversity among them.  相似文献   

20.
An electrophoretic analysis of 12 allozyme systems (14 loci, 40 alleles) was performed in the rodent genera Oryzomys and Oligoryzomys, in order to determine the levels of genetic variability within and among populations and species. One hundred and fifty-five individuals from 16 populations of Oryzomys russatus, Or. angouya, Oligoryzomys flavescens, and O1. nigripes species were trapped in nine Brazilian localities. Genetic divergence among populations, as well as the interpopulational gene diversity, was higher in Oryzomys than in Oligoryzomys. The dendrogram of the phenetic relationships among the 16 populations of these four species displays three clusters: the first one joins the O1. flavescens populations with those of O1. nigripes; the second groups the populations of Or. russatus, and the last assembles the populations of Or. angouya. The genetic parameters analyzed reveal that the species belonging to the genus Oryzomys are genetically more structured than those of Oligoryzomys, the latter presenting lower levels of intrademe genetic differentiation (G(ST)')  相似文献   

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