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1.
Information on population genetic structure and crop genetic diversity is important for genetically improving crop species and conserving threatened species. The PAL gene sequence is part of a multigene family that can be utilized to design DNA marker systems for genetic diversity and population structure investigation. In the current study, genetic diversity and population structure of 100 accessions of wild Pistacia species were investigated with 78 PAL markers. A protocol for using PAL sequences as DNA markers was developed. A total of 313 PAL loci were recognized, showing 100% polymorphism for PAL markers. The PAL markers produced relatively more observed and effective alleles in Pistacia falcata and Pistacia atlantica, with a higher Shannon’s information index and expected heterozygosity in P. atlantica, Pistacia vera and Pistacia mutica. Pairwise assessment of Nei’s genetic distance and genetic identity between populations revealed a close association between geographically isolated populations of Pistacia khinjuk and Pistacia chinensis. The accessions of wild Pistacia species had more genetic relationship among studied groups of species. Analysis of molecular variance indicated 19% among-population variation and 81% within-population variation for the PAL gene based DNA marker. Population structure analysis based on PAL revealed four groups with high genetic admixture among populations. The results establish PAL markers as a functional DNA marker system and provide important genetic information about accessions from wild populations of Pistacia species. 相似文献
2.
《林业研究》2016,(3)
Although cultivation and utilization of Pistacia are fully exploited, the evolutionary history of the Pistacia genus and the relationships among the species and accessions is still not well understood. The aim of this study was to analyze random amplified polymorphic DNA(RAPD) in a total of 50 accessions of wild pistachio species, which included five populations Pistacia vera, Pistacia khinjuk,Pistacia atlantica, Pistacia mutica, and Pistacia eurycarpa.High levels of genetic diversity were detected within wild pistachio accessions, as revealed by using the unweighted pair-group method with arithmetic averaging and supported via analysis of molecular variance. The objectives of this investigation were to estimate marker indices, polymorphic information contents(PICs), and genetic similarities(GS)for RAPD markers; assess the genetic diversity of Pistacia species, using GS estimated from RAPD fingerprints and molecular characterization; and facilitate the use of markers in inter-specific introgression and cultivar improvement.Out of the 149 polymerase chain reaction fragments that were scored, 146(97.98 %) were polymorphic. Genetic similarities ranged from 0.3 to 0.86 %, marker indices ranged from 2.98 to 17.74 %, and PICs ranged from 0.80 to0.99 %. Our results provided great molecular identification of all assayed genotypes, which have shown that there is large quantity of genetic diversity among the pistachio accessions. This finding might render striking information in breeding management strategies for genetic conservation and cultivar development. 相似文献
3.
Detailed chemical studies and RAPD analysis were done in different populations of Podophyllum hexandrum collected from high altitude regions of North Western Himalayas. Random amplified polymorphic DNA (RAPD) analysis revealed a high degree of genetic diversity among the 12 collected accessions, attributed to their geographical and climatic conditions. HPLC analysis also revealed variation in the concentration of two major marker compounds which lead to the identification of a chemotype. The study demonstrated that RAPD and chemical markers are very useful tools to compare the genetic relationship and pattern of variation among such prioritized and endangered medicinal plants. 相似文献
4.
湘鄂西地区珙桐天然群体遗传结构的研究 总被引：3，自引：0，他引：3
以珙桐叶为材料,对湘西和鄂西两天然珙桐群体的60个样品进行RAPD分析.结果表明,9个随机多态引物,获得24个多态标记位点,平均每个引物产生2.67个多态位点;湘西和鄂西两群体之间的遗传多样性差异不明显,Shannon指数分别为0.427 4和0.448 1;种内平均遗传多样性为0.326 9,群体内平均遗传多样性为0.297 6,群体间的遗传多样性为0.029 3,基因分化系数为0.089 6,基因流为5.079 2.两个天然珙桐群体的遗传相似性非常高,达到0.923 3,遗传距离为0.079 8;湘西群体的多态百分位率略高于鄂西.这表明,湘西和鄂西两群体间存在着非常频繁的基因流. 相似文献
5.
珙桐天然种群遗传多样性的ISSR标记分析 总被引：1，自引：1，他引：0
利用ISSR分子标记分析来自11个天然珙桐种群的遗传多样性。从100条引物中筛选出5条引物能扩增出稳定、清晰且具多态性的条带,共扩增出77个条带。其中74个为多态,多态条带百分率(PPB)为96.10%;各种群PPB值为37.66%～63.64%,平均为54.07%。种内Shannon多样性指数(HSP)为0.4849,种群内Shannon多样性指数(HPOP)为0.1886～0.3274,平均为0.2774。这表明珙桐在物种和种群水平上均维持较高的遗传多样性。分子方差分析显示,种群间与种群内遗传变异分别占总遗传变异的46.22%,53.78%,种群间呈高度遗传分化。种群间遗传距离与对应的地理距离呈显著正相关(r=0.546,P<0.01)。UPGMA法聚类分析将11个珙桐种群分为3组。研究结果为珙桐遗传资源保护策略制定提供有价值的种群遗传学信息。 相似文献
6.
白桦种群间木材纤维性状的表型变异与分子标记的遗传多态性 总被引：1，自引：0，他引：1
以东北地区的5个白桦天然种群为研究材料,在木材纤维形态性状测定的基础上,采用ISSR、RAPD分子标记研究了5个种群的遗传变异以及种群间纤维形态性状与DNA分子标记的相关性.结果表明:白桦天然林成熟材(18～31年生)的木材纤维长度在种群间差异不显著,纤维宽度和长宽比差异显著,帽儿山种群的木材纤维形态性状最好,汪清最差;利用ISSR和RAPD 2种标记检测5个白桦种群的遗传多样性,所得的研究结果基本一致,多态位点比率最高的为辽宁新宾种群,其次是帽儿山和汪清,而塔河和金山屯最低;ISSR标记的AMOVA分析表明白桦种群间的遗传变异占总遗传变异的10.82%;RAPD标记的AMOVA分析表明白桦种群间的遗传变异占总遗传变异的12.94%,研究结果均显示白桦的遗传变异主要发生在种群内部.利用2种标记技术的种群聚类结果基本一致,这一结果与基于木材纤维性状的表型聚类基本一致, 而且种群间遗传距离和地理距离之间存在一定的相关性. 相似文献
7.
《Fitoterapia》2014
Genetic, morphological and chemical variations of ten natural populations of Rauvolfia serpentina Benth. Ex. Kurtz. from Southern Western Ghats of India were assessed using RAPD markers reserpine content and morphological traits. An estimate of genetic diversity and differentiation between genotypes of breeding germplasm is of key importance for its improvement. Populations were collected from different geographical regions. Data obtained through three different methods were compared and the correlation among them was estimated. Statistical analysis showed significant differences for all horticultural characteristics among the accessions suggesting that selection for relevant characteristics could be possible. Variation in the content of Reserpine ranges from 0.192 g/100 g (population from Tusharagiri) to 1.312 g/100 g (population from Aryankavu). A high diversity within population and high genetic differentiation among them based on RAPDs were revealed caused both by habitat fragmentation of the low size of most populations and the low level of gene flow among them. The UPGMA dendrogram and PCA analysis based on reserpine content yielded higher separation among populations indicated specific adaptation of populations into clusters each of them including populations closed to their geographical origin. Genetic, chemical and morphological data were correlated based on Mantel test. Given the high differentiation among populations conservation strategies should take into account genetic diversity and chemical variation levels in relation to bioclimatic and geographic location of populations. Our results also indicate that RAPD approach along with horticultural analysis seemed to be best suited for assessing with high accuracy the genetic relationships among distinct R. serpentina accessions. 相似文献
8.
【目的】在我国野生土沉香被大量被采伐,种质资源越来越少,甚至面临消失的情况下,为了利用与保护野生土沉香提供理论依据,采用SRAP分子标记对其种源遗传多样性进行分析。【方法】基于我国11个土沉香种源群体和越南2个土沉香种源群体的SRAP结果,应用POPGEN32软件对遗传多样性参数进行计算。【结果】各群体Nei's基因多样度指数的变化范围为0.1715~0.5394,Shannon多样性指数的变化范围为0.2491~0.4837,多态位点百分比的变化范围为42.03%~76.81%。运用GenAlex 6.4软件对土沉香13个群体进行分子方差分析(Analysis of molecular variance,AMOVA),结果显示有30%的遗传变异来自土沉香群体间,70%的遗传变异来自土沉香群体内。【结论】13个土沉香种源有中度的遗传多样性和遗传分化,野生土沉香种质资源正日渐稀少,应该加强资源的保护与利用。 相似文献
9.
Cyclobalanopsis glauca is a dominant species of evergreen broad-leaved forests in mainland China. This study compares the genetic variation of an artificially regenerated population with its donor population and two other wild populations, by using RAPD markers. A total of 74 clear, reproducible bands were scored for 12 RAPD primers; 72 were polymorphic (P = 97.3%). AMOVA revealed that most genetic variation was within populations and only 10.35% was among populations. Various measures indicated that there is no difference in genetic diversity between the planted and the original populations. ΦST between the planted offspring population and the donor population was larger than those between the planted and other two natural populations, indicating that artificial regeneration might lead to biased genetic composition, given that temporal differentiation is usually lower than spatial differentiation. This divergence may be due to unequal seed production among the maternal individuals and viability differences among seeds. 相似文献
10.
Even with advanced gene technologies continued population improvement remains a key foundation for future genetic gain in
forest trees. Currently, this is served by maintaining genetic diversity while capturing genetic improvement, often through
structuring populations into a genetic hierarchy, setting population sizes, and managing pedigrees and inbreeding. In the
future, information from genomic technologies will complement classical approaches, such as common-garden field experiments,
for characterizing the genetic base and measuring and monitoring genetic diversity. This will entail directly measuring DNA
sequence diversity of both selectively neutral markers and functional genes. Calibrating neutral marker diversity against
functional diversity will become easier with functional genomics. For maintaining pedigree and managing inbreeding, genomic
information can be used to relax some traditional tenets of population management. With future knowledge of functional polymorphisms,
the better understanding of the nature and origins of genetic variation should enhance management of populations to both conserve
genetic diversity and exploit it by more efficient selection. Where fungal diseases threaten biotic crises, very large populations
may be needed, the requisite sizes often being very uncertain. Gene discovery holds enormous promise, but depends heavily
on comparative genomics, capitalizing on genomic information from Arabidopsis, Populus and Eucalyptus, and the increasing numbers of accessible ESTs. Much greater insights into non-codon mutational processes and rates should
also guide population management. A key challenge, however, will be to utilize information and apply tools cost-effectively.
Also, very detailed genomic information, exemplified by the poplar-genome sequencing, may allow earlier adaptation of technology
and development of new information in angiosperms than in gymnosperms. 相似文献
11.
《Journal of Sustainable Forestry》2013,32(3):75-90
Abstract The Japanese cedar, Cryptomeria japonica D. Don., is one of the most important endemic species in Japan. A long history of heavy logging has resulted in natural populations being discontinuously distributed and scattered among small, restricted areas. An understanding of the patterns of genetic variability among and within populations of C. japonica is important for conserving the genetic resources of this economically important species. We studied genetic variation by random amplified polymorphic DNA (RAPD) markers in C. japonica of Kyoto prefecture, western Japan. A total of 398 plants sampled from six natural populations were analyzed by ten arbitrarily chosen decamer primers, resulting in 50 highly reproducible RAPD bands. Analysis of molecular variance partitionated the RAPD variation into the among- and within population components. The within-population component accounted for 93.75% of the variation. The among-population component accounted for only 6.25%. Indirect estimates of gene flow indicated that the average number of migrants exchanged among six populations per generation was 3.72. A Mantel test for each population did not yield significant correlations between geographic and genetic distances. The extent and distribution of C. japonica diversity in the Kyoto prefecture is in agreement with the conclusion that long-lived, wind-pollinated, out-crossing species with wide ranges retain a considerable amount of genetic diversity within populations and exhibit little genetic differentiation among populations. 相似文献
12.
利用ISSR分子标记技术对14个居群的红花石蒜进行遗传多样性研究,结果表明:POPGEN32分析显示红花石蒜物种的遗传多样性很高,多态位点百分率为92.31%,Shannon指数(H)为0.459 7,Ne i指数(I)为0.302 5;居群水平的遗传多样性较低,多态位点百分率平均为49.65%,Shannon指数(H)平均为0.262 0,Ne i指数(I)平均为0.176 3;居群间的遗传分化系数(Gst)为0.503 5,基因流(Nm)为0.698 3。AMOVA分子变异分析显示:居群间遗传分化程度高,46.12%的变异发生在居群内,53.88%的变异发生于居群间。生境的片段化使居群间的基因流受阻,可能是居群间高遗传分化和居群水平低遗传多样性的主要原因。 相似文献
13.
以西伯利亚杏分布的核心区域燕山山脉地区的17个群体为材料,利用9对微卫星标记进行遗传多样性和遗传结构的分析。在533个个体扩增得到203个等位基因,每位点平均等位基因数为22.556个。分析表明燕山山脉西伯利亚杏群体具有较高的遗传多样性,每位点平均有效等位基因数(Ne)为5.714,多态位点百分率(P)为100%,期望杂合度(He)为0.788。根据有效等位基因数(Ne)、期望杂合度(He)和Shannon信息指数(I)3个遗传多样性参数,遗传多样性最高的群体为北京八达岭,其次为平泉榆树林子,而最低的群体为崇礼驿马图。群体间总的遗传分化系数FST为0.065,总的基因流Nm为3.836。分子方差分析(AMOVA)结果显示燕山山脉地区西伯利亚杏群体的遗传变异主要存在于群体内(95.62%)。Mantel检验发现遗传距离与地理距离呈显著相关性(r=0.5894,P<0.0001)。UPGMA聚类结果显示,地理距离接近的群体聚在一起,进一步验证了Mantel检验结果。基于上述分析结果,提出西伯利亚杏的种质收集策略。研究结果为西伯利亚杏可持续利用与保护提供一定的理论依据。 相似文献
14.
利用简单重复序列间扩增(ISSR)分子标记对分布于我国浙江和山东的8个山茶种群共240个个体进行了遗传结构分析。结果表明:筛选出的20条引物扩增得到210条清晰条带,其中184条为多态性条带,多态位点百分率(PPB)为87.62%。经POPGENE1.32软件分析,山茶种群平均多态位点百分率(PPB)为68.99%,Nei’s基因多样性指数(HE)为0.256 9,Shannon信息指数(H)为0.377 9,种群遗传多样性较高。基因分化系数Gst=0.182 9,表明遗传变异主要存在于种群内个体间。地理距离与遗传距离具有显著相关性(r=0.856 7,P<0.05),岛屿地理隔离对山茶种群的遗传分化具有重要影响。UPGMA聚类表明:浙江5个山茶种群间的遗传相似度较高,山东青岛的植物园种群和五四广场种群可能移植自长门岩岛。我国野生山茶资源受人为破坏严重,建议在加强现有岛屿自然种群就地保护力度的同时,建立山茶种质资源库,促进基因交流。 相似文献
15.
Taxus wallichiana is one of the most important medicinal tree species of the Himalayan region. Leaf and bark of the species yield an important
drug called taxol, which is used for treatment of many types of cancer. There is a serious threat to the existence of the
species due to over exploitation in its native habitat. Adequate information on the nature and the extent of genetic diversity
in this important species is required for developing suitable strategy for its conservation. Random amplified polymorphic
DNA (RAPD) and amplified fragment length polymorphism (AFLP) were used to assess genetic variation in nine natural populations
of T. wallichiana from western part of the Himalayan ranges. Both the markers revealed low genetic diversity in these populations. Average
heterozygosity for AFLP and RAPD were 0.3715 and 0.3072, respectively. ΦST values derived from molecular variance were 0.0855 and 0.1005 for AFLP and RAPD, respectively, whereas the corresponding
GST values were 0.1796 and 0.2140. Most part of the genetic variation was present within the populations. However, between population
variation was low but statistically significant, which suggested that the sampled populations might not constitute a single
panmictic population. Cluster analysis and Mantel’s correlation revealed that genetic differentiation broadly followed geographic
distribution of the populations. T. wallichiana thus urgently needs to be conserved using both in situ and ex situ conservation approaches. 相似文献
16.
以江西境内的5个毛红椿天然群体为研究对象,开展基于ISSR与SSR分子标记的群体遗传多样性研究。结果显示,5个群体总体表现为杂合子过剩,纯合子不足,总的遗传多样性偏低;物种水平的基因多样度（h）为0.2524,各群体基因多样度按大小排序为：九连山>官山>井冈山>马头山>岩泉。毛红椿群体规模小且林龄结构单一,推测这是造成其杂合子过剩但是基因多样性低下的主要原因。遗传分化指标（GST）显示受检测的毛红椿各群体间已发生显著分化,但群体内的遗传变异约占总变异的70%,仍是变异的主要来源;群体间基因流值（Nm）仅为0.596,多世代后的随机遗传漂变会逐渐加剧毛红椿群体遗传分化。为保证遗传完整性及保持群体的多样性水平,在江西境内可仅选择遗传多样性水平较高的九连山与官山两个群体来开展毛红椿的资源保存以及迁地保护。 相似文献
17.
The native cacao trees (Theobroma cacao L.) in south-eastern French Guiana represent a noteworthy fraction of the genetic diversity of this species. Several scientific surveys have led to the collection of numerous accessions, which provides an opportunity for investigating the pattern of genetic diversity in natural populations. Using a capillary electrophoresis genotyping system, we fingerprinted 189 wild trees in 18 natural populations. Based on the 15 loci SSR profiles, we analyzed the intra- and inter-population variation and their relationship with control clones. The global allelic richness was 4.87 alleles per locus, but was 2.4 on average within individual populations; gene diversity was 0.368 and observed heterozygosity was low (0.160). Major structuring was discovered in the metapopulation of French Guianan wild cacao trees (Fst = 0.20), which could be explained by the biological characteristics of the cacao tree and the climatic events that affected the Guianan forests in the Quaternary period. 相似文献
18.
[目的]从表型和分子2个角度揭示黄杨叶栒子(Cotoneaster buxifolius Lindl.)野生种群的遗传多样性。[方法]利用33个表型性状和ISSR分子标记对滇产野生黄杨叶栒子进行了遗传多样性分析。用PopGen 32软件计算多样性指数,用SPSS 16.0软件构建系统发育树系图。[结果]黄杨叶栒子种内表型性状在居群间存在着丰富的变异,居群间表型性状叶片大小变异系数达25.99%,萼裂片相关3个性状变异达40.66%,差异较大;24条ISSR引物扩增出228条带,其中,153条具有多态性,平均多态率为81.56%,Nei’s基因多样性指数和Shannon多样性指数分别为0.352 0和0.505 9,具有较高的遗传多样性;采用UPGMA法构建遗传关系聚类图,形态和分子标记的2种聚类结果基本一致:分布在同一地区的各个居群多数能聚在一起,地理位置的隔离促进了黄杨叶栒子居群间的遗传分化;个别居群未能与同一产区的其他居群聚在一起,而聚进了其他产区的居群之中,其原因可能是同一产区内各居群的小生境不完全相同,在不同产区内也有相似的小生境,导致黄杨叶栒子居群间发生了趋同进化。[结论]黄杨叶栒子遗传多样性丰富,居群间的亲缘关系及分布与地理位置、海拔位置有密切关系。 相似文献
19.
With growing concern about maintenance of genetic variation and conservation of gene resources, the question arises on the extent to which a planted population should be considered a resource able to preserve the gene pool of a species. In this study, levels of genetic diversity were assessed in natural and planted populations of Araucaria angustifolia using AFLPs and nuclear microsatellites, in order to assess the usefulness of planted forests in programs of species’ genetic resource conservation. In general, the genetic structure of the plantations was not strongly differentiated from the natural populations. For microsatellites, gene diversity (H) and allelic richness were significantly higher in plantations, while inbreeding was not different between planted and natural populations. For AFLPs, no significant difference was found between groups in the measures of genetic diversity. In the cluster analysis based on microsatellite data, plantations and natural populations from Santa Catarina State were grouped together, suggesting that plantations preserved genetic information very similar to natural populations. The cluster analysis of populations based on AFLP data differentiated plantations from natural populations. This pattern may be a result of genetic hitchhiking of AFLP fragments with genes under selective pressure due to plantations establishment and management. We suggest that the moderate to high level of genetic diversity retained in A. angustifolia populations after the intense fragmentation of the natural forest has the potential to supply plant material with sufficient genetic diversity for the species conservation through the establishment of planted forests. A sustainable management of the extant forest remnants and forestation/reforestation enterprises should additionally attend to trends revealed in previous studies concerning population structure and gene flow. 相似文献
20.
Victor O. Dania Olugbenga A. Osunlaja David O. Igwe 《Journal of Sustainable Forestry》2020,39(5):461-476
ABSTRACT Leaf blight is an important disease of teak which reduces photosynthetic rate and ultimate timber yield in infected trees. Symptomatic leaf samples were randomly collected from three forest reserves, Onigambari, Olokemeji and Omo in Southwest Nigeria. Genomic DNA from the samples was extracted using Cetyl Trimethyl Ammonium Bromide (CTAB) method and amplified with Inter Simple-Sequence Repeat (ISSR) markers to evaluate genetic diversity. Dendrogram analysis using UPMA procedure separated the accessions into 12 major groups with bootstrap values ranging from 51 to 62. The constructed dendogram showed that accessions from Onigambari forest reserve were genetically similar to those from the two other reserves. Principal component analysis (PCA) showed that the first, second and third axes accounted for 79.19%, 85.41%, and 88.11%, respectively, of the total molecular variation. All the four ISSR markers showed 100% polymorphism which induced the amplification of 48 alleles across the 39 teak accessions evaluated. Polymorphic information content (PIC) obtained from ISSR markers ranged from 0.6038 to 0.8886, while genetic diversity varied from 0.6288 to 0.8947. The inter-population genetic diversity and allelic richness observed in the study could be employed in breeding for resistance against leaf blight disease of teak. 相似文献