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1.
陕西省野生大豆种质资源的SSR遗传多样性研究   总被引：1，自引：0，他引：1  
为了研究陕西地区野生大豆的遗传多样性特点,利用SSR分子标记分析了陕西省6个野生大豆(Glycine soja)天然种群和1个栽培大豆(Glycine max)种群的遗传结构与遗传多样性。结果显示：13个位点共检测出113个等位基因,平均每个位点的等位基因数(A)为8.69个,等位基因数目范围为4~13个,有效等位基因数(Ne)范围为2.135(Satt590)~9.385 (Satt487),平均有效等因基因数为5.623;观察杂合度(Ho)变化范围为0.033~0.121,平均为0.080;预期杂合度(He)的变化范围为0.312~0.658,平均为0.482;种群平均Shannon遗传多样性指数(I)为0.657;野生大豆种群基因多样度比率(FST)为0.465。该研究显示,陕西省野生大豆具有较高水平的遗传多样性,野生大豆的遗传多样性普遍高于栽培大豆;随着海拔的不断升高,野生大豆遗传多样性变低;陕西中部、南部的野生大豆种质资源丰富、种群具有较高的遗传多样性,推测该区域为陕西省野生大豆的遗传多样性中心。  相似文献   

2.
海南两个自然保护区野生荔枝遗传多样性研究   总被引：1，自引：0，他引：1  
采用常规聚丙烯酰胺凝胶电泳技术,对海南吊罗山和霸王岭两个国家级自然保护区野生荔枝等位酶遗传多样性进行了研究。13个酶系统、18个酶位点的检测结果表明,两个自然保护区野生荔枝具有较低的居群间遗传变异水平和较高的居群内遗传变异。吊罗山保护区野生荔枝的遗传多样性参数为:P=61.1%,A=2.05,He=0.27。霸王岭居群野生荔枝的遗传多样性参数为:P=61.1%,A=2.05,He=0.28。两个群体的遗传分化极小,GST=0.047.居群间遗传一致度较高I=0.977。共检测到7个稀有等位基因。两个自然保护区的野生荔枝均有各自特有的稀有等位基因,都应采取措施予以保护。  相似文献   

3.
Approximately 7,000 accessions of Korean soybean (Glycine max (L.) Merrill) landraces, largely composed of three collections, the Korea Atomic Energy Research Institute’s soybean (KAS), the Korean Crop Experiment Station’s soybean (KLS) and the Korean Agricultural Development and Technology Center’s soybean (KADTC) collections, have been conserved at the Rural Development Administration (RDA) genebank in Korea. The accessions within collections were classified based on their traditional uses such as sauce soybean (SA), sprouted soybean (SP), soybean for cooking with rice (SCR), and OTHERS. A total of 2,758 accessions of Korean soybean landraces were used to profile and to evaluate genetic structure using six SSR loci. A total of 110 alleles were revealed by at the six SSR loci. The number of alleles per SSR locus ranged from 9 to 39 in Satt187 and Satt_074, respectively. The number of alleles ranged from 87 in the KADTC collection to 96 in the KLS collection, and from 63 in the SCR group to 95 in the SP group. Nei’s average genetic diversity ranged from 0.68 to 0.70 across three collections, and 0.64 to 0.69 across the usage groups. The average between-group differentiation (G st) was 0.9 among collections, and 4.1 among the usage groups. The similar average diversity among three collections implies that the genetic background of the three collections was quite similar or that there were a large number of duplicate accessions in three collections. The selection from the four groups classified based upon usage may be a useful way to select accessions for developing a Korean soybean landrace core collection at the RDA genebank. DNA profile information of accessions will provide indications of redundancies or omissions and aid in managing the soybean collection held at the RDA genebank. The information on diversity analysis could help to enlarge the genetic diversity of materials in breeding programs and could be used to develop a core collection.  相似文献   

4.
A. Haddioui  M. Baaziz 《Euphytica》2001,121(1):99-105
Based on polyacrylamide gel electrophoresis, nine natural populations of Atriplex halimus L., a perennial shrub, collected in different regions of Morocco, were studied for their genetic variation using isoenzyme polymorphism of the highly active enzyme systems: esterases (EST), acid phosphatases (ACP) and glutamate oxaloacetate transaminase (GOT). Different allozyme frequencies from 7 different loci were obtained for all populations of this halophyte species. High levels of genetic diversity were revealed. The mean number of alleles per locus (A = 1.9–2.0), the percentage of polymorphic loci (p = 71.4–85.7) and the mean expected heterozygosity (He = 0.339–0.385) showed an important variability in all populations. Gene diversity was essentially explained by the within population component. The between populations differentiation accounted for 8% of the whole diversity (FST, averaged over all loci, is 0.08). The relationships among the 9 populations were inferred from the Nei’s genetic distances. Four major groups were formed. The northern population ‘Tanger’, forming a unique group, was highly divergent from the other groups. It appeared that the genetic distance between all groups was related to the geographic distance that separates them. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

5.
L. X. Wang    R. X. Guan    Y. H. Li    F. Y. Lin    W. J. Luan    W. Li    Y. S. Ma    Z. X. Liu    R. Z. Chang    L. J. Qiu 《Plant Breeding》2008,127(1):56-61
To use, maintain and increase crop germplasm collections efficiently, it is important to assess the diversity of these collections. In this study, 1383 accessions of Chinese spring sowing soybean ( Glycine max ) were used for SSR analysis. In total, 1111 alleles were detected among these collections with an average number of alleles (NA) of 18.52 per locus. The genetic diversity index (PIC value) varied from 0.456 to 0.928 with an average of 0.815. Intensive breeding of cultivars have led to a decrease of genetic diversity. Random-repeated sampling within landraces of different geographical regions suggested that the ranking of both average NA and PIC values among different geographical regions were North spring soybean (Nsp) > South spring soybean (Ssp) > Northeast spring soybean (NEsp), but because of the uneven distribution of SSR variation patterns, the differences between them did not reach a significant level. There was a relationship between genetic distances and geographical distances among soybean populations from different regions, indicating a certain degree of geographical differentiation among Chinese soybean germplasm collections.  相似文献   

6.
R. K. Varshney    T. Mahendar    R. Aruna    S. N. Nigam    K. Neelima    V. Vadez    D. A. Hoisington 《Plant Breeding》2009,128(5):486-494
The ability to identify genetic variation is indispensable for effective management and use of genetic resources in crop breeding. Genetic variation among 189 groundnut ( Arachis hypogaea L.) accessions comprising landraces, cultivars, a mutant, advanced breeding lines and others (unknown genetic background) representing 29 countries and 10 geographical regions was assessed at 25 microsatellite or simple sequence repeat loci. A high number of alleles (265) were detected in the range of 3 (Ah1TC6G09) to 20 (Ah1TC11H06) with an average of 10.6 alleles per locus. The polymorphism information content value at these loci varied from 0.38 (Ah1TC6G09) to 0.88 (Ah1TC11H06) with an average of 0.70. A total of 59 unique alleles and 127 rare alleles were detected at almost all the loci assayed. Cluster analysis grouped 189 accessions into four clusters. In general, genotypes of South America and South Asia showed high level of diversity. Extraordinary level of natural genetic variation reported here provides opportunities to the groundnut community to make better decisions and define suitable strategies for harnessing the genetic variation in groundnut breeding.  相似文献   

7.
Seven wild populations of Anemonecoronaria were assessed for 11 phenotypic traits, most of them having economic value for the flower industry. The wild populations were sampled to represent the diversity in habitats, climates, rock and soil types, terrains, and elevations in Israel. AFLP analysis was carried out on 12 individuals from each of six out of the seven wild populations and for six individuals from the commercial cultivar ‘Mona-Lisa’. It was found that the Dorot population, which is located in the area bordering the semi-arid zone at the very end of the species distribution, exhibits extreme and different phenotypes with relatively low variability compared withthe other wild populations. The other six wild populations, that grow in more favorable geographic and climatic conditions exhibit phenotypes with larger plants, larger numbers of flowers and less dissected leaves. These populations were less uniform than that of Dorot. Genetic characterization by AFLP markers revealed a total of 165 bands. The wild populations exhibit wide variation within-population, with about 80% polymorphic bands and average gene diversity between pairs of about 30%. The Dorot population has the lowest genetic variation and the Megido population the highest. Thus, the phenotypic variation reflects the genetic variation. The cultivar ‘Mona-Lisa’, as expected, has much lower genetic variation. The Dorot population and the ‘Mona-Lisa’ cultivar were found to have the largest genetic distances from the other wild populations, and the highest genetic variation between themselves. Phenetic analysis yielded a dendrogram describing the genetic relatedness of these populations. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

8.
A total of 448 samples in five natural populations of wild rice (Oryza rufipogon) were collected in Cambodia. They were examined using 12 SSR and two chloroplast markers to evaluate the degree of variation among populations and the genetic structure within populations. In the two annual populations, the number of plants with homozygous alleles at all 12 SSR loci were high (66.3% and 79.5%), suggesting that these plants propagate mainly through self-pollination. In the three perennial populations, no individuals had all homozygous genotypes, but redundant genotypes resulted from clonal propagation were observed. Percentages of the redundant genotypes were highly varied (3.6%, 29.2% and 86.0%). This may be due to the different stable levels of environmental conditions. As for chloroplast genome, most of the wild plants showed the same chloroplast types as most Indica-type cultivars have. However, plants with different chloroplast types were maintained, even in the same population. In tropical Asian countries, many wild rice populations were observed under similar ecological conditions examined in this study. Therefore, the present results concerning population structure will be important to further elucidate genetic features of wild rice, and will also give strong clues to utilize and conserve wild natural genetic resources.  相似文献   

9.
Wild soybean (Glycine soja), as the progenitor of soybeans (G. max), is widely distributed in China and has been collected as a supplementary germplasm pool of soybeans. In this study, 375 wild soybean accessions from a set of genebank core collection were analysed for genetic diversity by using 42 simple sequence repeat primer pairs. The mean allele number per locus was 19.62. Ten‐percent unique alleles involving 35 or 83.33% loci differentiated among the geographical regions. The mean gene diversity (h) per locus was 0.89. A very low mean coefficient of gene differentiation (GST = 0.08) for geographical regions and a high mean within‐region gene diversity (HS = 0.81) were observed, indicating that most genetic diversity existed within the regions. There was an obvious relationship between genetic distance and geographical distance. The results showed multiple centers of genetic diversity for Chinese wild soybean in North China, the Huanghe River Valley, and Central China as well as the Changjiang River Valley, implicating multiple site origins of soybeans within China.  相似文献   

10.
Summary Six Festuca rubra populations from Europe and Scandinavia were studied for variation at three isozyme loci; phosphoglucoisomerase (PGI-2), glutamate oxaloacetate transaminase (GOT-3) and superoxide dismutase (SOD-1). Seven alleles were found at the Pgi-2 locus, four at the Got-3 locus and five at the Sod-1 locus. Most plants were heterozygous and up to five alleles were found in the same plant at the Pgi-2 locus. Each population could be distinguished by the presence or absence of certain alleles or by differences in the frequencies of the alleles present. Values for the Shannon diversity index were calculated which showed that there was considerable heterogeneity both within and between loci. In general, 53% of this diversity could be attributed to within population variation.  相似文献   

11.
Wild soybean, the progenitor of cultivated soybean, is an important gene pool for ongoing soybean breeding efforts. To identify yield-enhancing quantitative trait locus (QTL) or gene from wild soybean, 113 wild soybeans accessions were phenotyped for five yield-related traits and genotyped with 85 simple sequence repeat (SSR) markers to conduct association mapping. A total of 892 alleles were detected for the 85 SSR markers, with an average 10.49 alleles; the corresponding PIC values ranged from 0.07 to 0.92, with an average 0.73. The genetic diversity of each SSR marker ranged from 0.07 to 0.93, with an average 0.75. A total of 18 SSR markers were identified for the five traits. Two SSR markers, sct_010 and satt316, which are associated with the yield per plant were stably expressed over two years at two experimental locations. Our results suggested that association mapping can be an effective approach for identifying QTL from wild soybean.  相似文献   

12.
选用204对SSR标记对全国野生大豆群体(174份代表性样本)的基因组扫描,采用TASSEL软件的GLM (general linear model)方法对百粒重、开花期、成熟期、干豆腐得率、干豆乳得率和耐淹性性状值关联分析,解析与性状关联位点的优异等位变异,鉴别出一批与农艺、加工性状关联的优异等位变异及携带优异等位变异的载体材料;进一步分析极值表型材料的遗传构成。结果表明: (1)累计51个位点(次)与性状关联,有些标记同时与2个或多个性状相关联,可能是性状相关的遗传基础;关联位点中累计16位点(次)与连锁分析定位的QTL一致;(2)与地方品种群体和育成品种群体的关联位点比较,发现野生群体关联位点只有少数与之相同,群体间育种性状的遗传结构有明显差异。(3)与多性状关联的位点其等位变异对不同性状的效应方向可相同可不同,如GMES5532a-A332对百粒重和耐淹性的相对死苗率都是增效效应,而GMES5532a-A344对百粒重是减效效应,对相对死苗率是增效效应;(4)极值表型材料间的遗传构成有很大差异。表型值大的材料携带较多增效效应大的位点等位变异,例如N23349的百粒重是9.08 g,含有4个增效效应较大的位点等位变异;表型值小的材料携带较多减效效应大的位点等位变异,如N23387的百粒重是0.75 g,含有4个减效效应较大的位点等位变异。关联作图得到的信息可以弥补连锁定位信息的不足,尤其是全基因组位点上复等位变异的信息为育种提供了亲本选配和后代等位条带辅助选择的依据。  相似文献   

13.
The genetic structure of 175 genotypes of Theobroma cacao L. was investigated using 27 RFLP/cDNA loci. The number of alleles per locus was never higher than four and a high genetic diversity was found. Criollo genotypes appeared differentiated from Forastero genotypes. A deficiency of heterozygotes was found in all populations and some alleles were fixed in some populations. Within population gene diversity was high. When four morphological groups were considered, Upper Amazon Forastero was the most polymorphic and diverse population. Almost all the alleles of the whole species could be found within this group. Observed heterozygosity was the highest within Criollo and Trinitario populations but a certain proportion of homozygous genotypes was present in all groups. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

14.
利用39对SSR引物对海南114份普通野生稻、146份疣粒野生稻和81份药用野生稻进行扩增,从多态位点比率、平均等位基因数、香农指数等多个指标比较了3种野生稻遗传多样性的差异。结果表明,普通野生稻的遗传多样性最高,疣粒野生稻次之;在所检测的53个位点中,药用野生稻和疣粒野生稻的多态位点数分别为普通野生稻的1/7和2/7,等位基因数分别为普通野生稻的37%和39%;平均每个位点的实际杂合度,以普通野生稻杂合度最高（60%）,分别是疣粒野生稻和药用野生稻的4.6倍和6.6倍。Wright-统计量和聚类分析结果表明,普通野生稻群体的遗传多样性主要来自群间,当遗传一致度I等于0.53时,3个居群分别属于不同类群,因此建议将3个普通野生稻居群都纳入原生境保护点建设范围。同时,药用野生稻和疣粒野生稻无论居群间还是居群内遗传变异都很小,各居群个体间出现部分交叉,只有当I大于0.9时才分别聚为不同的类群,因此,在进行原生境保护时只需保护遗传多样性水平高的居群即可。  相似文献   

15.
为了研究豫南地区的野生大豆种质资源分布和种群间的亲缘关系,利用SSR分子标记采用20对引物对豫南地区12份野生大豆进行鉴定和遗传多样性分析。结果表明,20对引物对12份野生大豆共扩增63个等位基因,平均每对引物扩增3.1个等位基因;12份野生大豆在分子水平上发生了一定的遗传变化,聚类结果可以看出,12份材料聚类分成了三大类,SSR分子标记与材料的地理来源并没有明显的相关性。野生大豆的亲缘关系与生长的地理环境、表型性状等具有一定的相关性,同一区域收集到的野生大豆也表现出遗传分化。  相似文献   

16.
Genetic variation in two commercial varieties, ‘Liwally’ and ‘Barok’, and two Swedish natural populations of sheep's fescue, Festuca ovina s.l., was studied by means of starch gel electrophoresis. Variation in allele frequencies was found at the Dial, Gpi2, Got2, Pgdl, Pgm, Tpil and Tpi2 loci. ‘Liwally’, belonging to ssp. vallesiaca, showed clear differences compared to the other samples which belong to ssp. capillata and ssp. vulgaris. Genetic diversity, as measured by per cent polymorphic loci, number of alleles per locus and frequency of heterozygotes, was high in all samples in agreement with what has been found in other perennial, outcrossing mono-cotyledonous species with a wide distribution. The bred varieties and the wild populations did not statistically differ with respect to frequency of heterozygotes or number of alleles, though the last value was lower in the domesticated lines than in the natural populations. No significant deviation from the expected Hardy-Weinberg proportions was found in any of the samples.  相似文献   

17.
The NPGS-USDA core collection with 85 accessions of red clover, an important forage species, is little described. The goal of the present study was to evaluate the diversity of a set of accessions from the core collection at the morphological and molecular level in order to extract some valuable accessions for Brazilian red clover breeding programs. Twenty-one morphological traits, collected in field and greenhouse in South Brazil, and seven SSR markers were used to describe 57 accessions from the U.S. core collection and one population cultivated in Southern Brazil. Variation between accessions was large for most of the 21 morphological traits. A cluster analysis based on the morphological traits revealed five distinct clusters that separated the populations according to flowering earliness, as already described, but also according to persistency, growth habit and dry matter productivity. Over seven SSR loci, the number of alleles averaged 11.1 alleles per locus. Genetic diversity measured with SSR markers was high, with a mean expected heterozygosity of 0.86. An analysis of molecular variance revealed that the largest proportion of variation (83.6%) resided at the within population level. Although the molecular markers also separated accessions into five clusters, there was no coincidence between the composition of groups found with morphological and molecular data. Use of genetic diversity in breeding programs requires to use the most promising populations, to combine positive traits such as persistency and forage yield, and probably to use within population variation to detect valuable genotypes that could be used as parents of synthetic varieties.  相似文献   

18.
Summary Genetic variation was studied using enzyme polymorphism at 8 loci in ancient olive trees. These were being cultivated in 10 sites along a transect from North (Pre-Rif) to South (Anti-Atlas), involving the main ecological areas where the species is cultivated in Morocco. For the 328 trees studied, 16 alleles and 68 multilocus genotypes, of which one was present in more than half the individuals analysed, were detected. Eighty seven per cent of the total genetic diversity was attributable to within site variation and showed a high proportion of local genotypes. The highest values for both genotype number and heterozygosity were observed in the South of Morocco. Such high variation may be due to the partial domestication of olive material which may be derived from crosses between cultivars or between cultivars and feral or wild olive (oleaster) trees growing frequently in the Southern region. Genetic diversity in Moroccan olive, constitutes an important genetic resource which must be conserved for further breeding.  相似文献   

19.
Ke-Jing Wang  Xiang-Hua Li 《Euphytica》2012,186(3):817-830
To design appropriate strategies for ex situ and in situ conservation of wild soybean and safeguard the biosafety of the wild soybean gene pool when genetically modified soybeans are grown, it is important to understand its genetic characteristics, and to quantify gene flow and kinship within and between neighboring populations. We analyzed 9 pairs of neighboring populations of wild soybeans using 20 pairs of nuclear SSR markers. Results showed that Chinese wild soybean natural populations had outcrossing rates of 0–3.5% and that most populations contained many kinship families. The kinship families could be attributed to the accumulation of outcrossed offspring within populations during the history of population colonization. Wild soybean is very sensitive to environmental selection, which results in genetic differentiation of populations, and the emergence of specific alleles. We used an index τ to explain why genetic differences would exist between the pairwise populations; the interpopulation genetic differentiation chiefly consisted in the differences of allele frequencies over the genome. We found long-distance dispersal (1.5 km) of wild soybean seeds in a land ecosystem. There was close correlation between genetic and geographical distance among natural populations of Chinese wild soybean. Within a distance of 50 km, there was greater gene flow when the distance between populations was shorter. These findings have implications for ex situ and in situ conservation in an ecogeographical region, and also for protection of the gene pool from contamination by GM soybeans in wild soybean species.  相似文献   

20.
中国普通野生稻与栽培稻种SSR多样性的比较分析   总被引：5，自引：0，他引：5  
采用48对SSR引物对288份我国普通野生稻和栽培稻的遗传多样性进行比较分析。结果显示, 共检测到505个等位基因, 每个位点的等位基因数变幅为5~20, 平均10.5个; 平均Nei基因多样性指数(He)为0.731, 变幅为0.384(RM409)~0.905(RM206)。普通野生稻遗传多样性高于栽培稻种, 栽培稻等位基因数和平均Nei基因多样性指数分别为普通野生稻的70.2%和88.2%, 其中, 栽培稻地方品种和选育品种等位基因数分别为普通野生稻的65.4%和53.0%, 选育品种等位基因数仅为地方品种的81.1%。AMOVA分析表明, 总变异的10.3%是由于种间SSR遗传差异所引起的, 不同SSR位点种间的分化程度不同, 在0.7%~46.3%之间, 有43个位点种间遗传分化达到显著水平, 其中以RM427分化最为明显, 达46.3%。聚类分析表明, 中国普通野生稻总体偏粳, 极少数广东、海南材料偏籼。  相似文献   

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