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1.
V. Sérgio Emílio Dos Santos M. Aparecido Gimenes J. Francisco Montenegro Valls C. Romero Lopes 《Genetic Resources and Crop Evolution》2003,50(8):841-848
Some Arachis species are widely used as commercial plants, e.g. the groundnut A. hypogaea, an important source of good quality protein and oil, and A. pintoi and A. glabrata, that are utilized as forage species. Germplasm of most Arachis species is available in germplasm banks. However, little it is known about the genetic attributes of this germplasm, and mainly about its genetic variability, which is very important for its maintenance. In the present study RAPDs were used to assay the genetic variation within and among 48 accessions of five sections of the genus Arachis and to establish the genetic relationships among these accessions. Ten of 34 primers tested were selected for DNA amplification reactions since they yielded the largest numbers of polymorphic loci. A dendrogram was constructed based on data from the 10 primers selected. Eighty RAPD polymorphic bands were analyzed among the accessions studied. The relationships among species based on RAPDs were similar to those previously reported based on morphological, cytological and crossability data; demonstrating that RAPDs can be used to determine the genetic relationships among species of the different sections of the genus Arachis. In general, wide variation was found among accessions and low variation was found within the accessions that had two or more plants analyzed. However, higher polymorphism was found in the section Trierectoides and in one accession of A. major, indicating that generalizations should be avoided and each species should be analyzed in order to establish collection and maintenance strategies. 相似文献
2.
Target region amplification polymorphism (TRAP) markers were used to assess genetic variability among 38 germplasm accessions
and 10 commercial hybrids of spinach (Spinacia oleracea L.), an economically important leafy vegetable crop in many countries. Germplasm accessions with different geographic origins
and 10 commercial hybrids were examined. For assessing genetic diversity within accessions, DNA was extracted from 12 individual
seedlings from six germplasm accessions and two hybrids. A relatively high level of polymorphism was found within accessions
based on 59 polymorphic TRAP markers generated from one fixed primer derived from the Arabidopsis-like telomere repeat sequence and two arbitrary primers. For evaluating interaccession variability, DNA was extracted from
a bulk of six to 13 seedlings of each accession. Of the 492 fragments amplified by 12 primer combinations, 96 (19.5%) were
polymorphic and discriminated the 48 accessions from each other. The average pair-wise genetic similarity coefficient (Dice)
was 57.5% with a range from 23.2 to 85.3%. A dendrogram indicated that the genetic relationships among the accessions were
not highly associated with the geographic locations in which the germplasms were collected. The seven commercial hybrids were
grouped in three separate clusters, suggesting that the phenotype-based breeding activities tended to reduce the genetic variability.
This preliminary study demonstrated that TRAP markers are effective for fingerprinting and evaluating genetic variability
among spinach germplasms.
Mention of trade names or commercial products in this article is solely for the purpose of providing specific information
and does not imply recommendation or endorsement by the US Department of Agriculture.
The U.S. Government's right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged. 相似文献
3.
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
4.
Hironori Katayama Shiho Adachi Toshiya Yamamoto Chiyomi Uematsu 《Genetic Resources and Crop Evolution》2007,54(7):1573-1585
Iwateyamanashi (Pyrus ussuriensis var. aromatica) is one of the Pyrus species which grows wild in Japan. The number of Iwateyamanashi trees has been decreasing, so conservation and evaluation
is urgently needed. Over 500 accessions of Pyrus species collected from Iwate in northern Tohoku region are maintained at Kobe University as an Iwateyamanashi germplasm collection.
In order to investigate the genetic diversity, five SSR (simple sequence repeat) markers, developed from Japanese and European
pear were examined for 86 Pyrus individuals including 58 accessions from Iwate. These SSR loci could discriminate between all the Iwate accessions except
for 10 that bear seedless fruit, as well as determine the genetic diversity in Iwateyamanashi germplasms. High levels of variation
were detected in 41 alleles and the mean observed heterozygosity across 5 loci was 0.50 for the Iwate accessions. Seedless
accessions sharing identical SSR genotype with the local pear variety “Iwatetanenashi” were supposed to have been propagated
vegetatively via grafting. In an UPGMA phenogram, Japanese pear varieties (P. pyrifolia) were clustered into two groups with some Iwate accessions including seedless ones. Another 38 Iwate accessions were not
clustered clearly, and there was no clear relationship between these accessions and geographical distribution or morphological
characters. Allele frequency revealed that the Iwate accessions were genetically more divergent than the Japanese pear varieties.
Most Japanese pears possessed a 219 bp deletion at a spacer region between the accD and psaI genes in the chloroplast DNA (cpDNA), but other Pyrus species and two Iwateyamanashi trees did not. In the Iwate accessions, 79.3% had a deletion type cpDNA and others had a standard
type cpDNA without deletion. These results are indicative of the wide range of genetic diversity in the Iwate accessions which
include Japanese pear varieties. A combination of SSR and cpDNA analyses revealed high heterogeneity in Iwateyamanashi and
coexistence of Iwateyamanashi and hybrid progeny with P. pyrifolia. These could be reasons for the wide range of continuous morphological variation described previously. 相似文献
5.
6.
N. P. S. Dhillon R. Ranjana Kuldeep Singh I. Eduardo A. J. Monforte M. Pitrat N. K. Dhillon P. P. Singh 《Genetic Resources and Crop Evolution》2007,54(6):1267-1283
Diversity among 36 snapmelon landraces, collected from 2 agro-ecological regions of India (9 agro-climatic sub-regions), was
assayed using RAPD primers, morphological traits of plant habit and fruit, 2 yield-associated traits, pest and disease resistance
and biochemical composition (TSS, ascorbic acid, titrable acidity). Typical differences among accessions were observed in
plant and fruit characteristics and snapmelon germplasm with high titrable acidity and possessing resistance to downy mildew,
Cucumber mosaic virus, Zucchini yellow mosaic virus, Papaya ringspot virus, Aphis gossypii and Meloidogyne incognita was noticed in the collection. RAPD based grouping analysis revealed that Indian snapmelon was rich in genetic variation
and region and sub-region approach should be followed across India for acquisition of additional melon landraces. Accessions
of var. agrestis and var. momordica clustered together and there was a separate cluster of the accessions of var. reticulatus. Comparative analysis of the genetic variability among Indian snapmelons and an array of previously characterized reference
accessions of melon from Spain, Israel, Korea, Japan, Maldives, Iraq, Pakistan and India using SSRs showed that Indian snapmelon
germplasm contained a high degree of unique genetic variability which was needed to be preserved to broaden the genetic base
of melon germplasm available with the scientific community.
N. P. S. Dhillon and Ranjana contributed equally to this work and are considered the first authors. 相似文献
7.
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
8.
Milene Silvestrini Michele G. Junqueira Andréa C. Favarin Oliveiro Guerreiro-Filho Mirian P. Maluf Maria B. Silvarolla Carlos A. Colombo 《Genetic Resources and Crop Evolution》2007,54(6):1367-1379
Genetic diversity among 115 coffee accessions from the Coffea Germplasm Collection of IAC was assessed using SSR markers. The germplasm represents 73 accessions of Coffea arabica derived from spontaneous and subspontaneous plants in Ethiopia and Eritrea, species center of origin and diversity, 13 commercial
cultivars of C. arabica developed by the Breeding Program of IAC, 1 accession of C. arabica cv. ‘Geisha’, 13 accessions of C. arabica from Yemen, 5 accessions of C. eugenioides, 4 accessions of C. racemosa and 6 accessions of C. canephora. Genetic analysis was performed using average number of alleles per locus (A), proportion of polymorphic loci (P), Shannon’s genetic index (H′ and G′ST) and clustering analysis. All evaluated species were distinguished by a cluster analysis based on Jaccard’s coefficient.
Differentiation between the cultivated plants of C. arabica and accessions derived from spontaneous and subspontaneous plants was observed. Spontaneous and subspontaneous accessions
from Ethiopia were separated according to the geographical origin: east and west of the Great Rift Valley. Cultivated plants
showed a low genetic diversity with a division in two groups: accessions from Yemen (H′=0,028) and Brazilian commercial cultivars (H′=0,030). The results agreed with previously reported narrow genetic basis of cultivated plants of C. arabica and supported the hypotheses about domestication of the species. This study also showed a significant genetic diversity among
accessions from Ethiopia and Eritrea present in the Germplasm Collection of IAC. This diversity is specially observed in accessions
from Sidamo (H′=0,143), Kaffa (H′=0,142) and Illubabor (H′=0,147) indicating their importance as source of genetic variability for coffee breeding programs. 相似文献
9.
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
10.
Mulberry (Morus L.) is essential for the sericulture industry as the primary feed for the silkworm Bombyx mori L. in India, with its long tradition of practicing sericulture, has a large number of indigenous cultivars. Since knowledge on the genetic divergence of these cultivars/varieties is essential for proper conservation and utilization, Inter Simple Sequence Repeat (ISSR) profiling was employed to assess genetic relationships among 34 mulberry accessions, collected from different regions of India. By using 12 ISSR primers, which produced 72 markers displaying a high degree of polymorphism (94.4%), genetic dissimilarity coefficients were calculated for each pair of the accessions and clustering of the accessions with Unweighted Pair Group Method using Arithmetic average (UPGMA) analysis was done to unravel the genetic diversity among the accessions. The dissimilarity coefficients varied from 0.111 to 0.692. UPGMA analysis generated a dendrogram with six groups and five isolates. Clustering of the accessions did not correspond with the information on the geographic origin of many of the accessions. Two-dimensional representations of the relative positions of the accessions with regards to divergence using the first two canonical variates as co-ordinate axes revealed considerable variability among the cases in each group. Further, Discriminant Function Analysis (DFA) showed changes in the geographic origin of 11 accessions and species status of 20 accessions. 相似文献
11.
Mohammad R. Sabzalian Aghafakhr Mirlohi Ghodratollah Saeidi Mohammad T. Rabbani 《Genetic Resources and Crop Evolution》2009,56(8):1057-1064
Wild species of safflower, Carthamus oxyacanthus Bieb., is highly crossable with cultivated species, C. tinctorius L. and could be directly exploited in broadening safflower gene pool and improving the crop for biotic and abiotic stress
environments. In this study, genetic diversity among accessions of C. oxyacanthus and their relationships with cultivated safflower were evaluated using agro-morphological traits and polymorphic inter-simple
sequence repeats (ISSR) markers. Significant variation was observed among accessions particularly for seeds per capitulum,
seed yield per plant, harvest index and capitula per plant. Cluster analysis based on agro-morphological traits classified
the wild accessions in two groups according to their geographical regions, and separated them from the cultivated genotypes.
ISSR marker also revealed a high genetic variation among the accessions, and cluster analysis based on this marker divided
genotypes into four groups, with cultivated ones in a separate clade. Genetic variation observed among the wild safflower
germplasm at the DNA level was higher than the agro-morphological traits, indicating that ISSR is an effective marker system
for detecting diversity among safflower genotypes and their genetic relationships. Accessions of C. oxyacanthus with high genetic relationship to cultivated species could be used for interspecific hybridization in breeding programs of
safflower. 相似文献
12.
Fábio Luís Maciel Sergio Echeverrigaray Lee Tseng Sheng Gerald Felipe Gobbi Grazziotin 《Genetic Resources and Crop Evolution》2003,50(8):887-893
The genetic variation and relationships among 31 accessions of Phaseolus vulgaris L., and two representatives of Vigna unguiculata L., were evaluated by AFLP analysis. A total of 263 DNA fragments across all materials were scored using nine primer combinations, averaging 32 per primer. More than 95% of the amplification products showed polymorphism, indicating high variation at the DNA level among these accessions. Pair-wise genetic similarity (Jaccard's coefficient) ranged from 0.553 to 0.840, with a mean of 0.765. Twenty-three accessions (70%) clustered into three groups. A majority of the commercial cultivars (91%) clustered within a single group, whereas the landraces were distributed along all the variation. An apparent correlation with phaseolin types was detected. Results of this study suggest that Brazilian landraces truly represent the overall genetic variability of Phaseolus vulgaris, confirming the multiple origins of these materials, and their potential as a source of variation for breeding programs. 相似文献
13.
Yasuyuki Morimoto Patrick Maundu Makoto Kawase Hiroshi Fujimaki Hiroko Morishima 《Genetic Resources and Crop Evolution》2006,53(5):963-974
The present study was performed to investigate genetic diversity of Kenyan landraces of the white-flowered gourd (Lagenaria siceraria), which exhibits tremendous morphological variation. RAPD analyses were performed on 53 landraces of the cultivated species
L. siceraria and 42 accessions of three wild species (40 L. sphaerica, 1 L. abyssinica, and 1 L. breviflora). A total of 432 polymorphic bands were detected using 54 primers. The four species were clearly differentiated from one
another. Intra-specific variations were investigated with L. siceraria and its wild relative L. sphaerica. Landraces of the cultivated species collected from different ethnic communities or regions were differentiated. Morphological
variations were not associated with RAPD variations. Bitter landraces collected in Maasai communities showed two specific
RAPD bands. In the wild species, accessions collected from the eastern and western sides of the Great Rift Valley were genetically
differentiated from each other. In both species, genetic and geographical distance matrices computed among all pairs of accessions
were significantly correlated, implying that the observed geographical variation can be explained by the 'Isolation by distance
model'. Progeny plants derived from a common mother in L. siceraria showed a low level of segregation in RAPD pattern, suggesting that collected landraces are cultivated, maintaining their
inherent traits although they are monoecious and insect-pollinated, whereas the wild relative L. sphaerica showed a higher level of segregation. The morphological diversity observed among landraces of L. siceraria is the result of human selection and their genetic identities are maintained by inbreeding probably resulting from frequent
self-pollination. 相似文献
14.
Alake Christopher Olusanya 《Archives of Agronomy and Soil Science》2018,64(5):612-625
Amaranthus yields could benefit from our growing understanding of the genetic variability within and among individual species of local germplasm collections. Thirty-seven Amaranthus accessions representing three different species were evaluated for seed yield and yield components across two seasons. The objectives were to characterize the genetic variability of seed yield and its components across species and determine relationships among seed yield and its components by phenotypic correlation. Significant differences (P < 0.01) existed for all the evaluated traits among the accessions. Characters such as seed yield, stem girth and leaf length showed higher heritability estimates in A. cruentus (14) than in A. hypochondriacus (12) and A. dubius (11) accessions. Seed yield was significantly and positively correlated with stem girth and thousand seed weight. However, it was significantly and negatively correlated with number of days to flowering, plant height, leaf number, number of branches. The clustering of the accessions, which was partially in agreement with species grouping, will help in the identification of diverse parents for use in the breeding program. Enormous amount of genetic variability found in seed yield and its components among Nigerian Amaranthus accessions will offer opportunity for grain and leaf yield improvement through breeding. 相似文献
15.
S. I. Warwick R. K. Gugel T. McDonald K. C. Falk 《Genetic Resources and Crop Evolution》2006,53(2):297-312
Information on genetic diversity and genetic relationships among genotypes of Brassica carinata is currently limited. The objectives of this study were to evaluate patterns and levels of genetic diversity in B. carinata based on amplified fragment length polymorphisms (AFLP) as compared with Brassica juncea and Brassica nigra, and to evaluate agronomic and seed quality data for plants grown in the field in western Canada. A total of 296 AFLP bands
were generated from four primer pair combinations and scored for presence/absence in 66, 20 and 7 accessions of B. carinata, B. juncea and B. nigra, respectively. B. carinata was less genetically diverse than the other two species. Differences in diversity were evident in the proportion of polymorphic
loci within each species: 23, 35 and 50% for B. carinata, B. nigra and B. juncea, respectively. Pair-wise similarity measures based on the Jaccard coefficient were highest among accessions of B. carinata and showed the narrowest range: 0.911 (0.810–0.981) compared to B. nigra: 0.569 (0.438–0.660) and B. juncea: 0.715 (0.345–0.951). AFLP-based genetic distance information can be used by plant breeders to select diverse genotypes.
AFLPs are also useful for fingerprinting cultivars and two primer pair combinations were sufficient to uniquely identify all
the accessions of B. carinata. More variation among accessions was identified in the agronomic trial than had previously been described in studies of B. carinata in western Canada, but the data were too limited to draw conclusions regarding specific accessions. Overall, the findings
were in agreement with other published work describing the favourable agronomic potential of this species. 相似文献
16.
Cecilia Y. Kato Chifumi Nagai Paul H. Moore Francis Zee Minna S. Kim Denise L. Steiger Ray Ming 《Genetic Resources and Crop Evolution》2005,51(8):815-825
Pineapple (Ananas comosus (L.) Merr.) cultivars, often derived from somatic mutations, are propagated vegetatively. It has been suggested by isozyme data that there is little genetic variation among Smooth Cayenne cultivars. A thorough investigation of the genetic variation within the cultivated speciesAnanas comosus, particularly among commercial cultivars, will provide critical information needed for crop improvement and cultivar protection. One-hundred and forty-eight accessions ofA. comosus and 14 accessions of related species were evaluated with AFLP markers. The average genetic similarity ofA. comosus was 0.735 ranging from 0.549 to 0.972, suggesting a high degree of genetic variation within this species. With AFLP markers, discrete DNA fingerprints were detected for each commercial cultivar, breeding line, and intra-specific hybrid. Self-incompatibility, high levels of somatic mutation, and intraspecific hybridization may account for this high degree of variation. However, major cultivar groups of pineapple, such as Cayenne, Spanish, and Queen, could not be distinctively separated. These cultivar groups are based on morphological similarity, and the similar appearance can be caused by a few mutations that occurred on different genetic background. Our results suggest that there is abundant genetic variation within existing pineapple germplasm for selection, and discrete DNA fingerprinting patterns for commercial cultivars can be detected for cultivar protection. The genetic diversity and relationships of fourAnanas species are also discussed. 相似文献
17.
The genus Nicotiana is a member of the nightshade (Solanaceae) family, and is comprised of 70 currently recognized, naturally occurring species.
Genetic variability within N. tabacum L., the species of primary economic importance, was likely affected by several genetic bottlenecks. Nicotiana tabacum is a classic amphidiploid that arose after chance interspecific hybridization between N. sylvestris Spegazinni et Comes and a member of section Tomentosae, likely N. tomentosiformis Goodspeed, N. otophora Grisebach, or an introgressive hybrid between the two. Only a fraction of the genetic variability that existed in the diploid
progenitor gene pools probably entered into N. tabacum. Genetic drift, coupled with natural and human selection, subsequently resulted in the formation of narrow genetic pools
corresponding to modern commercial market classes. Genetic variability in Nicotiana has gained increased attention in recent years because of investment in Nicotiana genomics research, interest in development of tobacco products with reduced harm characteristics, and concentration on using
Nicotiana species for plant-based production of commercially useful proteins. A storehouse of genetic diversity for N. tabacum is available in approximately 1,900 accessions maintained by the United States Nicotiana Germplasm Collection. Seeds of 224 accessions representing 59 wild Nicotiana species are also maintained. The collection is currently maintained by North Carolina State University and is part of the
United States National Plant Germplasm System (NPGS). The collection’s curator satisfies hundreds of seed requests made annually
by scientists using Nicotiana germplasm for basic biological investigations and by researchers in the area of applied tobacco science. 相似文献
18.
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
19.
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
20.
Faris Hailu Arnulf Merker Harjit-Singh Getachew Belay Eva Johansson 《Genetic Resources and Crop Evolution》2006,53(6):1089-1098
The variability of 2420 plants of tetraploid (2n = 4x = 28, AABB genome) wheat germplasm representing 121 accessions from Ethiopia were evaluated for 23 agro-morphological traits at Debre Zeit Agricultural Research Center area, Akaki substation, during the 2003 main season using multivariate methods. This enabled to assess the extent and pattern of variation of the germplasm with respect to regions, altitude classes and species and to identify the major traits contributing to the diversity. The first three and two principal components explained about 83 and 80% of the total variance among regions and altitudinal class, respectively. In the first principal component plant height, days to heading, the length and density of the spike, and kernel color were the most important traits contributing to variation that explained about 50% of regional variance. Cluster analysis grouped the accessions into 15 clusters, with 9 accessions remaining ungrouped. Based on the observed patterns of variation, it is concluded that there exists great variation in the germplasm, which provides opportunities to be utilized for genetic improvement. 相似文献