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1.
Genetic diversity of eighteen accessions of Ae. geniculata (2n=28; UUMM) was assessed using the random amplified polymorphic DNA (RAPD) technique. We optimized RAPD conditions including the template DNA, the concentration of AmpliTaq DNA polymerase Stoffel fragment, and MgCl2 concentration for revealing polymorphisms. Thirty-eight decamer oligonucleotides were individually used as primers under optimized conditions. Seventeen of these primers produced polymorphic RAPDs among the 18 accessions of Ae. geniculata. Polymorphisms were recorded by noting presence or absence of an amplification product from the total genomic DNA. Comparisons of unique and shared amplification products of each pair of accessions were used to generate genetic similarity coefficients (GSCs). These GSCs were used to construct a phenogram using an unweighted pair-group method with arithmetical averages (UPGMA). The phenogram shows that RAPD data is useful in the measurement of genetic variation or similarity within a species. It also indicates that we can select eight or nine accessions of the eighteen accessions to maintain at least 80% genetic variability of the Chinese collection of Ae. geniculata.
Address for correspondence: Dr X-Y. Zhang, USDA-ARS-FRRL, Utah State University, Logan, UT 84322-6300, who is visiting the USA under an agreement between USDA-ARS and CMA-CAAS on germplasm resources. 相似文献
2.
Ilknur Solmaz Nebahat Sari Yildiz Aka-Kacar N. Yesim Yalcin-Mendi 《Genetic Resources and Crop Evolution》2010,57(5):763-771
Genetic diversity of the Turkish watermelon genetic resources was evaluated using different Citrullus species, wild relatives, foreign landraces, open pollinated (OP) and commercial hybrid cultivars by RAPD markers. The germplasm
was consisted of 303 accessions collected from various geographical regions. Twenty-two of 35 RAPD primers generated a total
of 241 reproducible bands, 146 (60.6%) of which were polymorphic. Based on the RAPD data the genetic similarity coefficients
were calculated and the dendrogram was constructed using UPGMA (Unweighted pair-group method with arithmetic average). Cluster
analysis of the 303 accessions employing RAPD data resulted in a multi-branched dendrogram indicating that most of the Turkish
accessions belonging to var. lanatus of Citrullus lanatus (Thunb.) Matsum et Nakai were grouped together. Accessions of different Citrullus species and Praecitrullus fistulosus (Stocks) Pangalo formed distant clusters from C. lanatus var. lanatus. Among 303 accessions, a subset of 56 accessions was selected representing different groups and a second dendrogram was constructed.
The genetic similarity coefficients (GS) within the Turkish accessions were ranged from 0.76 to 1.00 with 0.94 average indicating
that they are closely related. Taken together, our results indicated that low genetic variability exist among the watermelon
genetic resources collected from Turkey contrary to their remarkable phenotypic diversity. 相似文献
3.
Total 65 lotus accessions in genus Nelumbo mainly collected from China, were subjected to random amplified polymorphic DNA (RAPD) markers to estimate the genetic diversity
and to test the genetic basis of the relationships between morphotypes and molecular markers. Seventeen primers generated
a total of 195 highly reproducible and discernible loci, among which 173 were polymorphic. Percent polymorphism varied from
66.7 to 100 with an average of 88.72, and five primers out of them, OPC05, OPG10, OPN20, OPP09 and OPS17, showed 100% polymorphism.
A relatively high genetic diversity was detected among all the samples with the similarity coefficient values ranging from
0.45 to 0.85, and Nei’s gene diversity (h) 0.30, and Shannon index (I) 0.46. The UPGMA dendrogram clustered 65 accessions in four clusters and the clustering pattern showed two groups, N. nucifera ssp. nucifera and those accessions related to the American lotus, and some special cultivars, landraces, hybrids and the American lotus.
Principal Coordinate Analysis (PCA) further indicated that the genetic diversity of Nelumbo accessions was not evenly distributed, instead, was presented by a clustered distribution pattern. Similar to the results
revealed by the dendrogram, two main groups representing the two subspecies of N. nucifera, as well as some special landraces, cultivars of Chinese lotus, the Japanese lotus and hybrids out of the two groups were
obtained. Neither the UPGMA dendrogram nor the PCA analysis exhibited strict relationship with geographic distribution and
morphotypes among the accessions. 相似文献
4.
Toan Duc Pham Tri Minh Bui Gun Werlemark Tuyen Cach Bui Arnulf Merker Anders S. Carlsson 《Genetic Resources and Crop Evolution》2009,56(5):679-690
Sesame (Sesamum indicum L.) is a traditional oil crop cultivated throughout South East Asia. To estimate the genetic diversity of this crop in parts
at the region, 22 sesame accessions collected in Vietnam and Cambodia were analyzed using 10 RAPD markers. The 10 primers
generated 107 amplification products of which 88 were polymorphic fragments (83%). Genetic diversity of all populations was
Ht = 0.34 when estimated by Nei’s genetic diversity and species diversity was H′sp = 0.513 when estimated by Shannon diversity index. Genetic distance ranged from 0.03 to 0.43, with a mean genetic distance
of 0.23. The unweighted pair group method with arithmetic averages (UPGMA) cluster analysis for the 22 accessions divided
the material in four groups. The dendrogram revealed a clear division among the sesame accessions based on their geographical
region. Interestingly, some geographically distant accessions clustered in the same group, which might indicate the human
factor involved in the spreading of sesame varieties. The high level of polymorphism shown suggests that RAPD techniques can
also be useful for the selection of parents in sesame (Sesamum indicum L.) breeding program and for cultivar differentiation. 相似文献
5.
6.
The genus Aegilops L. is a very important genetic resource for the breeding of bread wheat Triticum aestivum. Therefore, an accurate and easy identification of Aegilops species is required. Traditionally, identification of Aegilops species has relied heavily on morphological characters. These characters, however, are either not variable enough among Aegilops species or too plastic to be used for identification at the species level. Molecular markers that are more stable within
species, therefore, could be the alternative strategy towards an accurate identification. Since the chloroplast DNA has a
lower level of evolution compared to the nuclear genome, an attempt was made in this study to investigate polymorphism in
the chloroplast DNA among 21 Aegilops species (including Ae. mutica that is now known as Amblyopyrum muticum) and between the latter and T. aestivum to generate markers for the diagnosis of all targeted species. Cleaved amplified polymorphic sequence (CAPS) applied on 22
coding and non-coding chloroplast regions using 80 endonucleases and sequencing of two of those regions revealed little polymorphism
between T. aestivum and the various Aegilops species examined and to a less extent was the variation among Aegilops species. Polymorphism observed among species analysed allowed the discrimination of T. aestivum and 12 Aegilops species. 相似文献
7.
Genetic diversity in Ethiopian hexaploid and tetraploid wheat germplasm assessed by microsatellite markers 总被引:4,自引:3,他引:4
Sentayehu Alamerew Sabina Chebotar Xiuqiang Huang Marion Röder Andreas Börner 《Genetic Resources and Crop Evolution》2004,51(5):559-567
The genetic diversity of a subset of the Ethiopian genebank collection maintained at the IPK Gatersleben was investigated applying 22 wheat microsatellites (WMS). The material consisted of 135 accessions belonging to the species T. aestivum L. (69 accessions), T. aethiopicum Jacubz. (54 accessions) and T. durum Desf. (12 accessions), obtained from different collection missions. In total 286 alleles were detected, ranging from 4 to 26 per WMS. For the three species T. aestivum, T. aethiopicum and T. durum on average 9.9, 7.9 and 7.9 alleles per locus, respectively, were observed. The average PIC values per locus were highly comparable for the three species analysed. Considering the genomes it was shown that the largest numbers of alleles per locus occurred in the B genome (18.4 alleles per locus) compared to A (10.1 alleles per locus) and D (8.2 alleles per locus) genomes. Genetic dissimilarity values between accessions were used to produce a dendrogram. All accessions could be distinguished, clustering in two large groups. Whereas T. aestivum formed a separate cluster, no clear discrimination between the two tetraploid species T. durum and T. aethiopicum was observed. 相似文献
8.
Genlou Sun 《Genetic Resources and Crop Evolution》2007,54(8):1737-1746
Elymus trachycaulus complex species are known for their morphological variability, but little is known about their genetic basis. The phylogenetic
relationships among the E. trachycaulus complex, and their systematic relation to other species in Triticeae remain unknown. Nucleotide diversity of ribulose-1,5
bisphosphate-carboxylase (rbcL) gene in E. trachycaulus complex species and several other Triticeae was first characterized and compared. A primary conclusion of the present study
is that nucleotide diversity for rbcL gene in E. trachycaulus species was detected with the estimates of nucleotide diversity θ = 0.00039 and π = 0.00043. The estimate of nucleotide diversity
in rbcL gene for species with different genome constitution here ranged from 0.00099 (π) and 0.00099 (θ) for the species with Ns
genome to 0.00226 (π) and 0.00291 (θ) for the species with St genome. The phylogenetic relationships of these species were
assessed using these rbcL sequences. A total of 47 variable positions including 19 parsimony-informative sites were detected among 24 accessions of
18 species/subspecies. The species with St, H/I and Ns genomes well separated from each other, and formed a three distinct
clades with higher bootstrap values support for both Parsimony and NJ analyses. The St genome containing species is sister
group of H/I genome containing species. Our result confirms that Pseudoroegneria is the maternal genome donor to these Elymus species studied here, regardless of their distribution. Elymus trachycaulus complex are more related to each other than to E. glaucescens, E. patagonicus, and E. solandri. This study suggested that Elymus species with StH genomes may form from multiple closely related sets of donors. 相似文献
9.
Amnon Levi Claude E. Thomas Anthony P. Keinath Todd C. Wehner 《Genetic Resources and Crop Evolution》2001,48(6):559-566
Genetic diversity was estimated among 42 U.S. PlantIntroduction (PI) accessions of the genusCitrullus (of these, 34 PIs are reported tohave disease resistance), and 5 watermelon cultivars, using 30RAPD primers. These primers produced 662 RAPD markers that could berated with high confidence. Based on these markers, geneticsimilarity coefficients were calculated and a dendrogram wasconstructed using the unweighted pair-group method witharithmetic average (UPGMA). The analysis delineated threemajor clusters. The first cluster consisted of a group of fivewatermelon cultivars, a group of C.lanatus var. lanatusaccessions, and a group of C.lanatus var. lanatusaccessions that contained some C.lanatus var. citroidesgenes. The second cluster consisted of the C.lanatus var. citroidesaccessions, while the third cluster consisted of theC. colocynthis accessions.The two C. lanatus clustersdifferentiated from each other and from the C.colocynthis cluster at the level of 58.8%and 38.9% genetic similarity, respectively. Assessment ofgenetic diversity among accessions that have been reported to havedisease resistance indicated that resistance to either anthracnose,downy mildew, powdery mildew, or watermelon mosaic virus is foundamong all major groups of Citrullus PIs.Additionally, resistance to gummy stem blight or Fusarium wilt mayexist among C. lanatus var.citroides PIs. This study demonstrates thatmolecular markers can be useful in assessing genetic diversity, andin sorting Citrullus PIs into phylogeneticgroups prior to their evaluation for disease or pestresistance. 相似文献
10.
Nidhi Rawat Vijay K. Tiwari Neelam Singh Gursharn S. Randhawa Kuldeep Singh Parveen Chhuneja Harcharan S. Dhaliwal 《Genetic Resources and Crop Evolution》2009,56(1):53-64
Grains of 80 accessions of nine species of wild Triticum and Aegilops along with 15 semi-dwarf cultivars of bread and durum wheat grown over 2 years at Indian Institute of Technology, Roorkee,
were analyzed for grain iron and zinc content. The bread and durum cultivars had very low content and little variability for
both of these micronutrients. The related non-progenitor wild species with S, U and M genomes showed up to 3–4 folds higher
iron and zinc content in their grains as compared to bread and durum wheat. For confirmation, two Ae. kotschyi Boiss. accessions were analyzed after ashing and were found to have more than 30% higher grain ash content than the wheat
cultivars containing more than 75% higher iron and 60% higher zinc than that of wheat. There were highly significant differences
for iron and zinc contents among various cultivars and wild relatives over both the years with very high broad sense heritability.
There was a significantly high positive correlation between flag leaf iron and grain iron (r = 0.82) and flag leaf zinc and grain zinc (r = 0.92) content of the selected donors suggesting that the leaf analysis could be used for early selection for high iron
and zinc content. ‘Chinese Spring’ (Ph
I
) was used for inducing homoeologous chromosome pairing between Aegilops and wheat genomes and transferring these useful traits from the wild species to the elite wheat cultivars. A majority of
the interspecific hybrids had higher leaf iron and zinc content than their wheat parents and equivalent or higher content
than their Aegilops parents suggesting that the parental Aegilops donors possess a more efficient system for uptake and translocation of the micronutrients which could ultimately be utilized
for wheat grain biofortification. Partially fertile to sterile BC1 derivatives with variable chromosomes of Aegilops species had also higher leaf iron and zinc content confirming the possibility of transfer of required variability. Some of
the fertile BC1F3 and BC2F2 derivatives had as high grain ash and grain ash iron and zinc content as that of the donor Aegilops parent. Further work on backcrossing, selfing, selection of fertile derivatives, leaf and grain analyses for iron and zinc
for developing biofortified bread and durum wheat cultivars is in progress.
Nidhi Rawat, Vijay K. Tiwari, and Neelam Singh have contributed equally to the work. 相似文献
11.
Nonnatus S. Bautista Duncan Vaughan A. H. M. Jayasuriya A. S. U. Liyanage Akito Kaga Norihiko Tomooka 《Genetic Resources and Crop Evolution》2006,53(3):631-640
The CC genome of Oryza is found in nine species of Oryza that are distributed on all continents having a tropical climate. Three diploid Oryza species with CC genome are found in Africa and Asia to Papua New Guinea. In southern South Asia these three CC genome diploid
species can be found, O. eichingeri and O. rhizomatis in Sri Lanka and O. officinalis in India. AA genome wild relatives of rice are also found in the same geographic region. Germplasm of both diploid CC and
AA genome Oryza germplasm has recently been collected from Sri Lanka. AFLP analysis was used to compare the genetic diversity of the two
Oryza genomes from a similar geographic region in southern South Asia. In addition, the diploid CC Oryza germplasm was also analyzed by RAPD and SSR methodologies and the combined results were analyzed. The results show that in
southern South Asia the diploid CC genome species have a high level of genetic diversity compared to the diploid AA genome
species. Molecular marker analysis revealed that populations of O. rhizomatis from northern and southeastern Sri Lanka are genetically differentiated. One accession of O. rhizomatis was aligned with O. eichingeri. This accession was collected from the site of O. rhizomatis that is the closest to a population of O. eichingeri. O. eichingeri showed lower genetic diversity than the other two diploid Oryza CC genome species. O. officinalis accessions from Assam, India, and China were genetically less diverged from O. eichingeri and O. rhizomatis than two accessions of O. officinalis from Kerala state, India.
The first two authors contributed equally to this research 相似文献
12.
Saowaluck Bua-in Yingyong Paisooksantivatana 《Genetic Resources and Crop Evolution》2010,57(3):405-414
The genetic relatedness among 51 accessions, 14 species of the genus Zingiber and genetic variability of a clonally propagated species, Zingiber montanum (Koenig) Link ex Dietr., from Thailand were studied using random amplified polymorphic DNA (RAPD) profiles. Twenty-nine random
primers gave reproducible amplification banding patterns of 607 polymorphic bands out of 611 scored bands accounting for 99.40%
polymorphism across the genotypes. Jaccard’s coefficient of similarity varied from 0.119 to 0.970, indicative of distant genetic
relatedness among the genotype studied. UPGMA clustering indicated eight distinct clusters of Zingiber, with a high cophenetic correlation (r = 1.00) value. Genetic variability in Z. montanum was exhibited by the collections from six regions of Thailand. High molecular variance (87%) within collection regions of
Z. montanum accessions was displayed by AMOVA and also explained the significant divergence among the sample from six collection regions.
Our results indicate that RAPD technique is useful for detecting the genetic relatedness within and among species of Zingiber and that high diversity exists in the clonally propagated species, Z. montanum. 相似文献
13.
Kazutoshi Okuno Kaoru Ebana Bayarsukh Noov Hisashi Yoshida 《Genetic Resources and Crop Evolution》1998,45(4):389-394
RAPD analysis of 112 accessions of Aegilops tauschii Coss. (genome DD), Ae. cylindrica Host (CCDD), Ae. crassa Boiss. (DDMM), Ae. biuncialis Vis. (UUMM) and Ae. triuncialis L. (UUCC) collected in the Central Asia and north Caucasia was conducted. Aegilops accessions were divided into two major groups, corresponding to the D genome species and the U genome species. These groups were also separated into sub-groups according to species, except for the Ae. tauschii-cylindrica complex of accessions from Central Asia. Aegilops tauschii from north Caucasia was divided into two varietal groups, tauschii and meyeri. The Central Asian accessions of Aegilops species were more diverse than the accessions from north Caucasia. Aegilops tauschii and Ae. cylindrica accessions from north Caucasia were genetically uniform. Associations between altitudal variation of Aegilops species and variability of RAPD markers were not found. 相似文献
14.
Surrinder K. Lattoo Rekha S. Dhar Shabnam Khan S. Bamotra Maharaj K. Bhan Autar K. Dhar Kuldip K. Gupta 《Genetic Resources and Crop Evolution》2008,55(1):33-43
Andrographis paniculata is a medicinal plant of immense therapeutic value. The present study was aimed to elucidate its genetic diversity based on
morphochemical and RAPD markers from 53 accessions belonging to 5 eco-geographic regions. Analysis of variance and D
2 statistics revealed significant differences in all the metric traits and sufficient inter-cluster distances indicating considerable
diversity among the accessions. The complementary approach of RAPD was used to evaluate the genetic dissimilarities among
all the accessions using 6 highly polymorphic primers. The average proportion of polymorphic loci across primers was 96.28%.
The molecular genetic diversity based on Shannon index per primer averaged 5.585 with values ranging from 3.08 to 8.70 indicating
towards wide genetic base. RAPD based UPGMA and D
2 cluster analysis also revealed that various accessions available in different eco-geographic regions might have originated
from native places of wild abundance. Similarity matrices were generated for molecular markers and morphometric data to determine
the degree of congruence between the two. A highly significant but low correlation (r = 0.547, P < 0.001) was obtained thus implying the correspondence between the two. The species is hermaphroditic and a habitual inbreeder.
The present study yielded a typical triangular congruence between its breeding system, morphometric traits and RAPD markers
thus elucidating the usefulness of complementary approaches to make diversity analysis more explanatory and purposeful for
optimum genetic amelioration and effective conservation of its genotypic variability. 相似文献
15.
Lihua Yao Xiaoyan Zheng Danying Cai Yuan Gao Kun Wang Yufen Cao Yuanwen Teng 《Genetic Resources and Crop Evolution》2010,57(6):841-851
A total of 8117 suitable SSR-contaning ESTs were acquired by screening from a Malus EST database, among which dinudeotide SSRs were the most abundant repeat motif, within which, CT/TC followed by AG/GA were
predominant. Based on the suitable sequences, we developed 147 SSR primer pairs, of which 94 pairs gave amplifications within
the expected size range while 65 pairs were found to be polymorphic after a preliminary test. Eighteen primer pairs selected
randomly were further used to assess genetic relationship among 20 Malus species or cultivars. As a result, these primers displayed high level of polymorphism with a mean of 6.94 alleles per locus
and UPGMA cluster analysis grouped twenty Malus accessions into five groups at the similarity level of 0.6800 that were largely congruent to the traditional taxonomy. Subsequently,
all of the 94 primer pairs were tested on four accessions of Pyrus to evaluate the transferability of the markers, and 40 of 72 functional SSRs produced polymorphic amplicons from which 8
SSR loci selected randomly were employed to analyze genetic diversity and relationship among a collection of Pyrus. The 8 primer pairs produced expected bands with the similar size in apples with an average of 7.375 alleles per locus. The
observed heterozygosity of different loci ranged from 0.29 (MES96) to 0.83 (MES138), with a mean of 0.55 which is lower than 0.63 reported in genome-derived SSR marker analysis in Pyrus. The UPGMA dendrogram was similar to the previous results obtained by using RAPD and AFLP markers. Our results showed that
these EST-SSR markers displayed reliable amplification and considerable polymorphism in both Malus and Pyrus, and will contribute to the knowledge of genetic study of Malus and genetically closed genera. 相似文献
16.
Chloroplast simple sequence repeats (cpSSRs) are widely distributed in the chloroplast genomes of all plant species, and are frequently employed for genotypic and phylogenetic analysis. However, information on intra- and interspecies variation in cpSSRs is lacking. In this study, we sequenced four intergenic (non-coding) chloroplast DNA regions in 57 accessions of 12 tetraploid, and 16 accessions of 4 hexaploid species of Triticum and Aegilops. These sequence data added to our previous data for diploid species in the same chloroplast regions. Intra- and interspecific genetic variation was analyzed for a total of 189 accessions of 13 diploid, 12 tetraploid, and 4 hexaploid species of Triticum and Aegilops, such that all species were represented by multiple accessions. The data were used to infer phylogenetic relationships within and among Triticum and Aegilops species. Based on this robust phylogenetic tree, seven of eight cpSSR loci clearly exhibited “size homoplasy,” referring to the fact that cpSSRs of identical size and DNA sequence can arise even if the alleles are not descended from a common ancestor. These data indicate that cpSSRs should be used with caution in phylogenetic analyzes. Interestingly, as observed from several previous studies, our data also suggest that observed mutation rates may increase significantly when mononucleotide (homopolymer) repeat numbers reach or exceed 9 bp. In the present report, using this sequence data set involving cpSSRs, 81 unique haplotypes among 189 accessions were detected, and five tetraploid Triticum and Aegilops species were successfully identified and genotyped. Our results indicate that combinations of nucleotide substitutions, indels and SSRs of chloroplast nucleotide sequences are available for genotyping at the species accession level. 相似文献
17.
Igor G. Loskutov 《Genetic Resources and Crop Evolution》2008,55(2):211-220
This article presents literary review and results analysis of evaluation of representative set of oat accessions of all Avena L. species. Results of complex study of major morphological characters and utilization of the karyotype structure data confirmed
by the results of RAPD and avenin spectrum analysis are presented. Relationships of genomes of different Avena species at each ploidy level are discussed. Two genomes form the base of all Avena species, namely the A and C genomes. Results of the evaluation of several characteristics of the oat species and their geographical
distribution are analysed. Probable evolutionary pathway of Avena species are suggested. Most likely the centres of origin of genus Avena L. are determined. 相似文献
18.
Oryza officinalis complex is the largest and the most complicated group in the genus Oryza L., consisting of about ten species with the B, C, BC, CD, and E genomes. Taxonomy and identification of the species, particularly those with the B, C and BC genomes, are difficult due to the similar morphology and overlapping distribution of some species. The difference in ploidy levels of some species adds more complexity. In the present study, we surveyed 64 accessions of rice germplasm in the O. officinalis complex using RFLP analysis of PCR-amplified Adh genes in addition to chromosome counting. The results confirmed that all O. rhizomatis accessions are diploids with the C genome, whereas all O. minuta accessions are tetraploids having the BC genome. However, both diploid and tetraploid forms were found for the accessions identified in the genebank as O. officinalis, O. punctata and O. eichingeri. The tetraploid form of O. officinalis with the BC genome is exclusively distributed in India and has been described as O. malampuzhaensis. The tetraploid form of O. punctata which has been called O. schweinfurthiana by some workers was found to be as widely distributed as its diploid form in Africa. It is noteworthy that two accessions that had been determined as tetraploid O. officinalis were actually belonging to a species with the CD genome (O. latifolia). Our results promote a better understanding of the genomic constitutions of many accessions in the O. officinalis complex and correct determination of the genebank material, which serves as an important basis of germplasm cataloguing for further research and utilization. 相似文献
19.
M. R. Naghavi M. J. Aghaei A. R. Taleei M. Omidi J. Mozafari M. E. Hassani 《Genetic Resources and Crop Evolution》2009,56(4):499-506
Simple sequence repeats (SSRs), highly dispersed nucleotide sequences in genomes, were used for germplasm analysis and estimation
of the genetic relationship of the D-genome among 52 accessions of T. aestivum (AABBDD), Ae. tauschii (DtDt), Ae. cylindrica (CCDcDc) and Ae. crassa (MMDcr1Dcr1), collected from 13 different sites in Iran. A set of 21 microsatellite primers, from various locations on the seven D-genome
chromosomes, revealed a high level of polymorphism. A total of 273 alleles were detected across all four species and the number
of alleles per each microsatellite marker varied from 3 to 27. The highest genetic diversity occurred in Ae. tauschii followed by Ae. crassa, and the genetic distance was the smallest between Ae. tauschii and Ae. cylindrica. Data obtained in this study supports the view that genetic variability in the D-genome of hexaploid wheat is less than in
Ae. tauschii. The highest number of unique alleles was observed within Ae. crassa accessions, indicating this species as a great potential source of novel genes for bread wheat improvement. Knowledge of
genetic diversity in Aegilops species provides different levels of information which is important in the management of germplasm resources. 相似文献
20.
Sandra Patricia Toquica Fernando Rodríguez Edgar Martínez Myriam Cristina Duque Joe Tohme 《Genetic Resources and Crop Evolution》2003,50(6):639-647
Using AFLPs, 71 peppers (Capsicum) accessions from the species C. chinense Jacq., C. baccatum L., C. annuum L. and C. frutescens L. from indigenous communities of the Amazon Department (Colombia) were studied to assess the genetic diversity of the collections, and delineate species gene groups. Ten additional accessions were included as a reference species group. Three clusters were identified in the Amazonian accessions by Multiple Correspondence Analyses (MCA) and a dendrogram from the UPGMA analyses of Nei – Li genetic similarity. The clusters correspond to gene groups of the species Capsicum chinense (the majority of the accessions), C. baccatum and the complex annuum - frutescens. A fourth cluster corresponds to the reference accession C. pubescens. The MCA analyses accounted for 95% of the total variation. The total genetic variation was low (Ht 0.119) and a genetic diversity index (Gst) of 0.331 was obtained. This suggests a limited genetic diversity of the accessions and a close relatedness of the species. This study is the first molecular marker assessment of genetic diversity for peppers from the Colombian Amazon, and provides information of biodiversity that can be employed in the preservation and use of Capsicum germplasm. 相似文献