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1.
Amplified fragment length polymorphism (AFLP) analysis was used to evaluate the genetic relationships and diversities of Chinese
vegetable mustards. Fourteen pairs of primers generated a total of 366 scorable fragments among 16 accessions of Brassica juncea studied, of which 296 bands were polymorphic with an average of 21.1% polymorphic bands per primer combination. Genetic similarities
were obtained using Nei and Li similarity coefficients, and a dendrogram of the 16 accessions was made by UPGMA clustering
method. The Nei and Li Similarity coefficient value ranged from 0.63 to 0.88. This result indicated that the 16 accessions
of B. juncea possessed high level genetic variations. The cluster analysis showed that the vegetable mustards could be grouped into two
main groups and some minor rami, which was partially in accordance with the traditional classification that based on different
edible organs of vegetable mustards. The incongruity between morphological and molecular classification might be attributed
to the high selection pressure during domestication of Chinese vegetable mustards, producing some accessions with similar
genetic backgrounds evolving into abundant morphological variations. The great diversification among Chinese vegetable mustards
not only provides an excellent object for molecular evolution research of B. juncea but also is of great value for widening the genetic basis of breeding programs and breeding materials selection. Besides,
our study also indicates that AFLP are informative and can provide significant insights for genetic diversity research in
B. juncea. 相似文献
2.
A. Levi K. R. Harris W. P. Wechter C. S. Kousik J. A. Thies 《Genetic Resources and Crop Evolution》2010,57(8):1191-1205
The round melon Praecitrullus fistulosus (Stocks) Pangalo has been cultivated in Asia since ancient times and has been considered an underexploited crop in the western
world. In the USA, there is an increased interest in using P. fistulosus as a commercial vegetable, and possibly as a rootstock for grafting watermelon, melon, or cucumber. However, the taxonomic
classification of P. fistulosus is incomplete and for many years it has been considered a close relative of watermelon [Citrullus lanatus subsp. vulgaris (Schrad. ex Eckl. et Zeyh.) Fursa] and was previously classified as Citrullus lanatus subsp. fistulosus (Stocks) Duthie et J.B. Fuller. Here, we used two sets of DNA markers to assess the genetic similarity of P. fistulosus in relation to Citrullus spp. {including Citrullus lanatus subsp. vulgaris, C. lanatus subsp. lanatus, Citroides group [also known as C. lanatus (Thunb.) Matsum. et Nakai subsp. lanatus var. citroides (Bailey) Mansf. ex Greb.], and C. colocynthis (L.) Schrad.}, Cucumis spp. (including C. melo, C. sativus, C. anguria, C. meeusei, C. zeyheri), Benincasa hispida (Thunb.) Cogn., Lagenaria
siceraria (Mol.) Standl. and Cucurbita spp. (including C. moschata Duchesne and the winter squash C. maxima Duchesne). The first marker set comprised 501 markers that were produced by 38 primer pairs derived from watermelon expressed
sequenced tags (ESTs) containing simple sequence repeat (SSR) motifs (designated as EST-SSR primers; produced 311 markers),
and by 18 primer pairs derived from ESTs that do not contain SSR motives (designated here as EST-PCR primers; produced 190
markers). The second marker set comprised 628 markers that were produced by 18 sequence related amplified polymorphism (SRAP)
primer pairs. The phylogenetic data indicated that among these cucurbit species, the wax gourd B. hispida is the closest to the P. fistulosus. Pollen observations, using light microscopy, indicated that each of the cucurbit genera examined here has unique pollen
morphology. The Cucurbita spp. have globular pollen grains with a stigmatic surface. The L.
siceraria has polygonal pollen grains with symmetrical boundaries, while the Citrullus spp. and Cucumis spp. have ovular (conical) and triangular shaped pollen grains (respectively). The B. hispida and P. fistulosus have spherical or semispherical pollen grains. These pollen features appear to be in agreement with the phylogenetic relationships
of these two species based on DNA markers. Analysis with 12 SRAP primer pairs revealed low genetic diversity among 18 United
States Plant Introductions (PIs) of P. fistulosus, indicating the need to expand the germplasm collection of this cucurbit crop. 相似文献
3.
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
4.
Xingquan Zeng Yajuan Wang Weiyan Li Changyou Wang Xinlun Liu Wanquan Ji 《Genetic Resources and Crop Evolution》2010,57(8):1141-1150
In order to evaluate and compare the germplasm resources of wheat in Tibet, we analyzed the genetic diversity of 136 Triticum aestivum ssp. tibetanum Shao and 119 Tibetan wheat landraces (Triticum aestivum L.) by using Intron-Splice Junction (ISJ) primers. The results showed that polymorphism of PCR products were obtained by
33 primer combinations, which accounted for 11% of the 300 primer combinations produced by 26 ISJ primers. A total of 333
stable bands can be amplified from the T. aestivum ssp. tibetanum Shao and 243 bands were polymorphic, which accounted for 72.9% of the total bands. Tibetan wheat Landraces produced 316 stable
bands, of which 197 bands were polymorphic. The polymorphic bands accounted for 62.34% of the total bands produced from Tibetan
wheat landraces. The genetic diversity of T. aestivum ssp. tibetanum Shao was higher than that of Tibetan wheat landraces in Tibet, suggesting that T. aestivum ssp. tibetanum Shao can be used as important genetic resource for the breeding and genetic improvement of wheat in Tibet. Matrix (1, 0)
was generated according to the presence or absence of the bands produced from a particular wheat accession. Clustering and
principle coordinates analysis showed that T. aestivum ssp. tibetanum Shao and Tibetan wheat landraces were divided into two groups. We conclude that high polymorphisms produced by ISJ primers
can reflect the genetic diversity between T. aestivum ssp. tibetanum Shao and Tibetan wheat landraces. 相似文献
5.
Xiao-Hua Qi Ming-Fang Zhang Jing-Hua Yang 《Genetic Resources and Crop Evolution》2007,54(8):1709-1716
Sequence variation of nuclear internal transcribed spacer regions of ribosomal DNA (ITS1, 5.8S rRNA and ITS2) from Chinese
vegetable mustards (AB-genome) and its putative parents Brassica rapa (the A-genome) and Brassica nigra (the B-genome) were used to investigate the molecular phylogeny and the probable evolutional pattern of this amphidiploid
species that uniquely formed in China. Totally, 16 accessions of Chinese vegetable mustard those covering nearly all the diverse
variations were included in this study, and together with three accessions of B. rapa and one accession of B. nigra. The results disclosed two strongly supported clades, one containing four accessions of vegetable mustard which have closer
relationship with B-genome species “B.nigra” lineage and the other containing 12 accessions of B. juncea and three A-genome accessions. This classification was in disagreement with the evidence from chloroplast DNA, mitochondrial
DNA, nuclear DNA restriction fragment length polymorphism (RFLP), which suggested that B. juncea was closely related to the A-genome type. For the incongruence, we speculated that the B. juncea crops derived from Chinese have evolved through different recombined events of the diploid morphutypes and evolved unidirectional
concerted evolution. The traditional phenotypic classification of B. juncea was not wholly supported by ITS results, and hence the phylogenetic relationships among these subspecies need to be reconsidered
on molecular level. 相似文献
6.
Masashi Yamamoto Akiko Takakura Aika Tanabe Sayuri Teramoto Masayuki Kita 《Genetic Resources and Crop Evolution》2017,64(4):805-814
Citrus depressa Hayata is an indigenous mandarin species on the Ryukyu Islands located in the subtropical region of Japan. We deduced its phylogenetic relationships by evaluating accessions grown on various Ryukyu Islands via cleaved amplified polymorphic sequence analysis of cpDNA and sequence-related amplified polymorphism (SRAP). The cpDNA results indicated that C. depressa could be classified into two types. SRAP revealed patterns of diversity within C. depressa consistent with our cpDNA results. These results indicate that maternal origin may influence or is correlated with the constitution of the nuclear genome of C. depressa. Another Japanese mandarin species, Citrus tachibana (Makino) Tanaka was distinguished from C. depressa by SRAP markers. Moreover, both C. depressa and C. tachibana could be distinguished from other Citrus species. Our results suggest that Japanese mandarin possesses a characteristic genome with the genus Citrus. 相似文献
7.
A fertile amphidiploid × Brassicoraphanus (RRCC, 2n = 36) between Raphanus sativus cv. HQ-04 (2n = 18, RR) and Brassica alboglabra Bailey (2n = 18, CC) was synthesized and successive selections for seed fertility were made from F4 to F10. F10 plants exhibited good fertility with 14.9 seeds per siliqua and 32.3 g seeds per plant. Cytological observation revealed
that frequent secondary pairing occurred among 3 chromosome pairs in pollen mother cells of plants (F4) with lower fertility, but not of plants with high fertility (F10). GISH analysis indicated that these F10 plants included the expected 18 chromosomes from R. sativus and B. alboglabra, respectively, but they lost approximately 27.6% R. sativus and 35.6% B. alboglabra AFLP (amplified fragment length polymorphism) bands. The crossability of the Raphanobrassica with R. sativus and 5 Brassica species (13 cultivars) were investigated. Seeds or F1 seedlings were easy to be produced from crosses × Brassicoraphanus × R. sativus, and B. napus, B. juncea and B. carinata × Brassicoraphanus. Fewer seeds or seedlings were obtained from crosses × Brassicoraphanus × B. napus, B. juncea and B. carinata. However, few seeds were harvested in the reciprocals of × Brassicoraphanus with B. rapa and B. oleracea. The possible cause of fertility improvements and the potential of the present × Brassicoraphanus for breeding were discussed. 相似文献
8.
Xiaoping Ren Jiaquan Huang Boshou Liao Xiaojie Zhang Huifang Jiang 《Genetic Resources and Crop Evolution》2010,57(6):903-913
The Arachis genus is native to South America, and contains 70–80 described species assembled into nine sections. A better understanding
of the level of speciation and taxonomic relationships is a prerequisite to the effective use of Arachis species in peanut breeding programs. Forty-eight genotypes representing 19 species in 6 sections were evaluated to assay
the genetic variability within and among species, and 10 recombinant lines and those parents were identified with introgression
of Arachis species chromosome segments into A.
hypogaea genome using SRAP markers. Sixty of sixty-four SRAP primers tested were selected for DNA amplification reactions. A dendrogram
and principal component analysis were constructed based on 353 SRAP polymorphic bands of the accessions. The number of scored
polymorphic bands per each primer combination varied from 1 to 25 with an average of 5.9 per reaction. Estimates of genetic
distance among the 48 accessions Arachis species ranged from 0.11 to 0.76. A-genome accessions 475845 (A. duranensis), and 331197 (A. villosa) were most closely associated to A.
hypogaea. The first two PCAs accounted for 77.74% (62.02 and 15.72%) of the total variation observed and separated the different genomic
groups. SRAPs also identified introgression of Arachis species chromosome segments into A.
hypogaea. genome with 10 recombinant lines and those parents. The present results indicated that SRAPs can be used to determine the
genetic relationships among species of the different sections of the genus Arachis and to identify introgression of Arachis genus chromosome segments into A.
hypogaea genome. 相似文献
9.
There is a need to understand whether weed genetic diversity is the same among different populations, especially between those
exposed to herbicide selection and other without exposure history. Inter-simple sequence repeat (ISSR) were used to assess
level and patterns of genetic diversity in wild Brassica juncea (L.) Czern. et Coss. populations. A total of 93 plants from 24 wild populations in China were analysed by eight primers resulting
in 86 highly reproducible ISSR bands. The analysis of molecular variance (AMOVA) with distances among individuals corrected
for the dominant nature of ISSRs showed that most of the variation (54.09%) occurred among populations, and the remaining
45.91% variance was attributed to differences among individuals within populations. The high differentiation was, perhaps,
due to limited gene flow (Nm < 1.0) of this species. Though highest gene diversity was observed in resistant B. juncea population, the overall distribution of diversity across China was not geographic dependent. High F
ST value (0.541) corroborated AMOVA partitioning and provided significant evidence for population differentiation in wild B. juncea. UPGMA cluster analyses, based on Nei’s genetic distance, revealed grouping pattern geographically. Based on these results,
the factors affect weed population genetic diversity and implication for herbicide resistance evolution were discussed in
the context of transgenic crops advent and increasing herbicide usage in China. 相似文献
10.
Muhammad Youssef Arif Saeed Alhammadi Jorge Humberto Ramírez-Prado Lorenzo Felipe Sánchez-Teyer Rosa María Escobedo-GraciaMedrano 《Genetic Resources and Crop Evolution》2018,65(2):577-590
Here, two Punica species, viz., P. protopunica Balf. fil., reported as native to Socotra, and P. granatum L., were compared for the first time. Analysis of one P. protopunica and eleven P. granatum accessions was performed using three molecular markers, i.e., sequence related amplified polymorphism (SRAP), target region amplification polymorphism (TRAP), and intron targeted amplified polymorphism (ITAP), along with analysis of pgWD40 sequences, a gene involved in anthocyanin biosynthesis. All markers revealed the relationship between the two species and placed them at 33% similarity. SRAP, TRAP, and ITAP generated a total of 299, 260, and 160 bands, respectively. Of these, 78, 74, and 41 bands were specific for P. protopunica, and 92, 85, and 57 bands, respectively, were shared between both species. Sequence analysis of pgWD40~870 bp amplicons exhibited 100% identity among P. granatum accessions and 98% identity to that of P. protopunica. Phylogenetic analysis of WD40 sequences from monocot and dicot species, including both Punica species confirmed the relation between P. protopunica and P. granatum, supporting earlier reports that P. protopunica could be an ancestral species of P. granatum. Furthermore, the genetic diversity among and within P. granatum accessions from Egypt (3), Mexico (5), and Yemen (3) was assessed. Molecular marker-based relationships among region-bulked accessions was approximately the same (~90% similarity), whereas the degree of genetic variation was altered within each region. Specific bands (alleles) for accessions of each region along with those shared among them were identified. Thus, these bands could be used for pomegranate genotyping and breeding programs. 相似文献
11.
S. Ganesh Ram K. T. Parthiban R. Senthil Kumar V. Thiruvengadam M. Paramathma 《Genetic Resources and Crop Evolution》2008,55(6):803-809
The genus Jatropha is native of tropical America with more than 200 species that are widely distributed in tropics with a promise for use as
an oil crop for biodiesel. This investigation was carried out to assess the genetic diversity of 12 Jatropha species based on random amplified polymorphic DNA markers. From 26 random primers used, 18 primers gave reproducible amplification
banding patterns of 112 polymorphic bands out of 134 bands scored accounting for 80.2% polymorphism across the genotypes.
Three primers viz., OPA 4, OPF 11, and OPD 14 generated 100% polymorphic patterns. The polymorphic information content was
highest for the primer OPD 14 (0.50) followed by the primers OPF 11 and OPAD 11 (0.48). Jaccard’s coefficient of similarity
varied from 0.00 to 0.85, indicative of high level of genetic variation among the genotypes studied. UPGMA cluster analysis
indicated three distinct clusters, one comprising all accessions of J. curcas L., while second included six species viz., J. ramanadensis Ramam., J. gossypiifolia L., J. podagrica Hook., J. tanjorensis J. L. Ellis et Saroja J. villosa Wight and J. integerrima Jacq. J. glandulifera Roxb. remained distinct and formed third cluster indicating its higher genetic distinctness from other species. The overall
grouping pattern of clustering corresponds well with principal component analysis confirming patterns of genetic diversity
observed among the species. The result provides valid guidelines for collection, conservation and characterization of Jatropha genetic resources. 相似文献
12.
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
13.
Perilla (Lamiaceae) contains one tetraploid species, P. frutescens (L.) Britt. and three diploid species, P. citriodora (Makino) Nakai, P. hirtella Nakai and P. setoyensis G. Honda. Tetraploid species have been traditionally cultivated in Asia for their seed oil and for their fragrant leaves
that are used as medicine or as a garnish for fish. The center of diversity is still obscure. To conserve the genetic resources,
it is important to know the diversity of the tetraploid species. The three diploid species, which are possible parents of
the tetraploid species, are all believed to be indigenous to Japan. Their distribution in China and Korea was clarified on
the basis of herbarium and field surveys. The tetraploid species is assumed to have originated somewhere around the mid-to
downstream area of the Changjiang River. Though Perilla is not cultivated as often in these areas as in northern China, Korea, the Himalayan region, or Myanmar, these areas should
also be important for the conservation of genetic resources of tetraploid Perilla crops because of the expected high genetic diversity. 相似文献
14.
Sonia?Marghali Olivier?Panaud Fran?oise?Lamy Salma?Ghariani Aboubakry?Sarr Mohamed?Marrakchi Neila?Trifi-Farah
Amplified fragment length polymorphism (AFLP) markers were used to characterize the genetic diversity within and among natural populations and cultivars of Hedysarum coronarium. Twelve populations within Tunisia were evaluated with three AFLP primer combinations. A total of 207 reproducible bands was detected of which 178 (86%) were polymorphic. The great discriminative power of AFLP markers and their ability to represent genetic relationships among Hedysarum plants was demonstrated. Genetic diversity within and among populations was assessed through Principal Component Analysis (PCA) and cluster analysis by using the Neighbor-joining clustering algorithm. AFLP technology has provided evidence of a high degree of intra- and inter-population genetic diversity in H. coronarium. AFLP banding patterns provided molecular markers correlated with the plants’ geotropism. In addition, AFLP markers can differentiate wild accessions from cultivars. Moreover, geographical origins did not correspond to population clustering. 相似文献
15.
Amplified fragment length polymorphism markers were used to assess the genetic relatedness between Dioscorea alata and nine other edible Dioscorea. These species include D. abyssinica Hoch., D. bulbifera L., D. cayenensis-rotundata Lamk. et Poir., D. esculenta Burk., D. nummularia Lam., D. pentaphylla L., D. persimilis Prain. et Burk., D. transversa Br. and D. trifida L. Four successive studies were conducted with emphasis on the genetic relationship within D. alata and among species of the Enantiophyllum section from Vanuatu. Study 1 was carried out to select a set of polymorphic primer
pairs using 11 combinations and eight species belonging to five distinct sections. The four most polymorphic primer pairs
were used in study 2 among six species of the Enantiophyllum section. Study 3 focussed mainly on the genetic relationship
among 83 accessions of D. alata, mostly from Vanuatu (78 acc.) but also from Benin, Guadeloupe, New Caledonia and Vietnam. The ploidy level of 53 accessions
was determined and results indicated the presence of tetraploid, hexaploid and octoploid cultivars. Study 4, included 35 accessions
of D. alata, D. nummularia and D. transversa and was conducted using two primer pairs to verify the taxonomical identity of the cultivars `langlang', `maro' and `netsar'
from Vanuatu. The overall results indicated that each accession can be fingerprinted uniquely with AFLP. D. alata is an heterogeneous species which shares a common genetic background with D. nummularia and `langlang', `maro' and `netsar'. UPGMA cluster analysis revealed the existence of three major groups of genotypes within
D. alata, each assembling accessions from distant geographical origins and different ploidy levels. The analysis also revealed that
`langlang', `maro' and `netsar' clustered together with the cultivar `wael' (D. transversa) from New Caledonia. Results are discussed in the paper. 相似文献
16.
Togha Jenabi Hojjatollah Saeidi Mohammad Reza Rahiminejad 《Genetic Resources and Crop Evolution》2011,58(4):497-505
The mountain rye Secale strictum is native to the Middle East and is the progenitor of the cultivated rye. Regarding lack of information about the genetic
diversity of this species in Iran, this study was aimed to evaluate its genetic variation and to examine the patterns of diversity
related to the varieties and geography. Fifteen wheat and rye derived microsatellite markers were used to achieve this aim.
High levels of diversity, with an average number of 6.1 alleles per locus (ranging up to 11) and high level polymorphism with
polymorphism rate averaging 0.624 (between populations) and 0.357 (within populations) were observed among 125 individuals
from 19 populations collected from various regions of Iran. The Northwestern populations showed the highest and the Northern
populations showed the lowest polymorphism and diversity. One population of the Northwest of the country was notably closer
in its allele range to the S. cereale accessions used as outgroup. No taxon or geographic specific marker was detected, suggesting high gene flow between the populations,
however some groupings which can be related to the geographic regions and varieties, were evident. The analysis of molecular
variance attributed same portions of genetic diversity to the within and between populations with no significant variation
among different geographic regions. The results of this study indicated that the Iranian genepool of Secale strictum is valuable to search for new useful alleles for crop improvement. 相似文献
17.
Reliable characterization of the variation among wild and cultivated yams in Nigeria is essential for improved management
and efficient utilization of yam genetic resources. RAPD and double stringency PCR (DS-PCR) analyses were used to investigate
genetic relationships and the extent of redundancy among 30 accessions of two cultivated, and 35 accessions of four wild yam
species collected from Nigeria. Twenty-five selected random decamer and two microsatellite primers were used individually
and in combination to generate DNA profiles for each accession of the six Dioscorea species. The number of amplified fragments varied from 7 to 18 fragments per primer/primer combination. Different levels
of intraspecific genetic diversity were found, with Dioscorea rotundata Poir. being the most variable. Based on identical profiles for the RAPD and DS-PCR primers, 12 duplication groups consisting
of a total number of 37 accessions were observed in the present study. An UPGMA analysis grouped the majority of plants according
to the species. Cultivated yams belonging to the D. cayenensis–rotundata species complex, which were classified into seven morphotypes/varietal groups, could be clearly separated into two major
groups corresponding to D. rotundata Poir. and D. cayenensis Lam. D. cayenensis cultivars exhibited a low level of intraspecific variation and were genetically close to the wild species Dioscorea burkilliana J. Miège. D. rotundata cultivars classified into six varietal groups showed a high degree of DNA polymorphism and were separated into two major
groups that appeared most closely related to Dioscorea praehensilis Benth. and Dioscorea liebrechtsiana de Wild. We propose, based on these results, that cultivars classified into D. cayenensis should be considered as a taxon separate from D. rotundata. The implications of intraspecific variability for the ex situ conservation of wild and cultivated yam germplasm in Nigeria are discussed. 相似文献
18.
The genus Arachis is divided into nine taxonomic sections. Section Arachis is composed of annual and perennial species, while section Heteranthae has only annual species. The objective of this study was to investigate the genetic relationships among 15 Brazilian annual
accessions from Arachis and Heteranthae using RAPD markers. Twenty-seven primers were tested, of which nine produced unique fingerprintings for all the accessions
studied. A total of 88 polymorphic fragments were scored and the number of fragments per primer varied from 6 to 17 with a
mean of 9.8. Two specific markers were identified for species with 2n = 18 chromosomes. The phenogram derived from the RAPD data corroborated the morphological classification. The bootstrap analysis
divided the genotypes into two significant clusters. The first cluster contained all the section Arachis species, and the accessions within it were grouped based upon the presence or absence of the ‘A’ pair and the number of chromosomes.
The second cluster grouped all accessions belonging to section Heteranthae. 相似文献
19.
Yomara Rozo Lorena Quintero Mauricio Parra Carlos Rodríguez Luz Marina Melgarejo 《Genetic Resources and Crop Evolution》2009,56(1):77-83
Couepia is a genus distributed in tropical regions of America. The nut of some Couepia species is used as fresh fruit and oil source for local communities. Despite its critical situation of conservation and its
economic potential, there is a lack of information on the genetic variability of Couepia species. This study examines AFLP variation among 40 accessions of Couepia collected in the Colombian Amazonian region, representing two species: Couepia
dolichopoda and Couepia
subcordata. The individuals were examined for 96 markers generated from four EcoRI/MseI primer pairs, with 80% polymorphism across all accessions studied. According to cluster analysis, 40 accessions were grouped
into two major clusters, corresponding to the two species analyzed, except one case whose situation is discussed. In C. dolichopoda accessions, significant correlation between the clustering pattern and the geographical origin was detected; the extent of
variation within and among its collect sites was examined by AMOVA. The knowledge about the genetic variability of the accessions
examined contributes to development of Couepia conservational efforts. 相似文献
20.
The genetic diversity and similarities among 32 Kengyilia accessions, distributed to 14 species and one variety were analyzed by using random amplified microsatellite polymorphism
(RAMP) markers. Of the 160 RAMP primer combinations tested, 40 (25%) produced polymorphic and clear bands. A total of 264
bands were produced by 40 primer combinations, among which 231 out of 264 bands (87.5%) were polymorphic. Two to 11 polymorphic
bands could be amplified from each primer combination, with an average of 5.8 bands. The data of 264 bands were used for RAMP
assay. By NTSYS-pc program, genetic similarity coefficients were generated and dendrogram was constructed using UPGMA. The
genetic similarity coefficients ranged from 0.477 to 0.965 with the mean of 0.714. The results showed as follows: (1) distinct
genetic differences were present among the different species; (2) the different accessions in a species were clustered together,
respectively, which had larger genetic similarities and closer relations; (3) the species with similar morphological characters
and the species from the same areas or neighboring geographical regions were clustered together; (4) the lowest genetic similarity
was found between K. hirsuta (PI531618) and K. laxiflora (PI531631), while the highest genetic similarity was observed between K. hirsuta (Y2364) and K. hirsuta (Y2368); (5) RAMP results are basically comparable with those obtained from studies on morphology and cytology. It is a useful
method for analysis of the genetic diversity and similarities in Kengyilia. 相似文献