共查询到20条相似文献,搜索用时 15 毫秒
1.
E. V. Metakovsky G. Branlard 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(2):209-218
Analysis of gliadin electrophoretic (APAGE) patterns made it possible to identify 79 alleles at six Gli-1 and Gli-2 loci (from 9 to 18 per locus) and 173 gliadin genotypes in the 187 French common wheat cultivars considered. Six new alleles
were registered in the catalogue of gliadin alleles. The genetic diversity of French common wheats was found to be high (H=0.714) and had not changed much during the last 25–50 years. Analysis of genetic distances showed some gradual changes in
French wheat germplasm over the course of time. Genetic distances between French and several European wheat germplasm were
analysed; genotypes of European wheats were found to relate very distantly to Canadian genotypes. The considerable differentiation
of wheat genotypes from different countries and cereal companies might be caused by breeders’ personal preferences and by
hidden natural selection specific to each local environment. In French cultivars, genetic variation in earliness, and in the
North/South habit of the cultivars studied, correlated significantly with allelic variation at Gli-B1, Gli-A2 and Gli-D2 for earliness, and at Gli-D2 for the North/ South habit. Early and late cultivars are grown mainly in Southern and Northern France, respectively (r
2=0.30). Cultivars having either the 1B/1R translocation or allele Gli-D2g are, on average, later and more resistant to cold; they hence are grown in the North of France. Alternatively, cultivars
with the allele Gli-D2m are earlier and cold-sensitive, and are grown in the South of France.
Received: 5 February 1997 / Accepted: 19 September 1997 相似文献
2.
T. Fahima G. L. Sun A. Beharav T. Krugman A. Beiles E. Nevo 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(3-4):434-447
Genetic diversity in random amplified polymorphic DNAs (RAPDs) was studied in 110 genotypes of the tetraploid wild progenitor
of wheat, Triticum dicoccoides, from 11 populations sampled in Israel and Turkey. Our results show high level of diversity of RAPD markers in wild wheat
populations in Israel. The ten primers used in this study amplified 59 scorable RAPD loci of which 48 (81.4%) were polymorphic
and 11 monomorphic. RAPD analysis was found to be highly effective in distinguishing genotypes of T. dicoccoides originating from diverse ecogeographical sites in Israel and Turkey, with 95.5% of the 100 genotypes correctly classified
into sites of origin by discriminant analysis based on RAPD genotyping. However, interpopulation genetic distances showed
no association with geographic distance between the population sites of origin, negating a simple isolation by distance model.
Spatial autocorrelation of RAPD frequencies suggests that migration is not influential. Our present RAPD results are non-random
and in agreement with the previously obtained allozyme patterns, although the genetic diversity values obtained with RAPDs
are much higher than the allozyme values. Significant correlates of RAPD markers with various climatic and soil factors suggest
that, as in the case of allozymes, natural selection causes adaptive RAPD ecogeographical differentiation. The results obtained
suggest that RAPD markers are useful for the estimation of genetic diversity in wild material of T. dicoccoides and the identification of suitable parents for the development of mapping populations for the tagging of agronomically important
traits derived from T. dicoccoides.
Received: 13 July 1998 / Accepted: 13 August 1998 相似文献
3.
J. G. Paull K. J. Chalmers A. Karakousis J. M. Kretschmer S. Manning P. Langridge 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(3-4):435-446
Restriction fragment length polymorphisms (RFLPs) have been used to characterise the genetic diversity of wheat (Triticum aestivum) germplasm. One hundred and twenty-four accessions comprising all major Australian wheat varieties and lines important for
breeding purposes were assayed for RFLPs with clones of known genetic location and selected to give uniform genome coverage.
The objectives of this study were to determine RFLP-based genetic similarity between accessions and to derive associations
between agronomically significant traits and RFLP phenotypes. Ninety-eight probes screened against genomic DNA digested with
five restriction endonucleases detected a total of 1968 polymorphic fragments. Genetic similarity (GS) calculated from the
RFLP data ranged from 0.004 to 0.409 between accessions, with a mean of 0.18. Cluster analysis based on GS estimates produced
four groupings that were generally consistent with available pedigree information. Comparisons of the RFLP phenotypes of accessions
containing disease resistance genes present on introgressed alien segments enabled the identification of specific alleles
characteristic of these regions. Associations were derived for a range of stem-rust, leaf-rust and yellow-rust resistance
genes. These results suggest that RFLP analysis can be used for the characterisation and grouping of elite breeding material
of wheat and RFLP profiling can identify chromosome segments associated with agronomic traits.
Received: 10 March 1997 / Accepted: 28 July 1997 相似文献
4.
Twenty Pisolithus tinctorius isolates from different geographic locations and different hosts were characterized by the random amplified polymorphic DNA
technique. Thirteen arbitrary primers generated 87 DNA fragments, all of them polymorphic. These data were used to calculate
genetic distances among the isolates. The pairwise genetic distances ranged from 1 to 100%, with an average of 58.7%. Cluster
analysis based on the amplified fragments grouped the isolates according to their host and geographical origins. Group I contained
isolates collected in Brazil and group II those collected in the Northern Hemisphere. In addition to the diversity seen at
the molecular level, the isolates also showed host specificity. Greenhouse experiments demonstrated that isolates from the
Northern Hemisphere colonized mainly Pinus whereas isolates from Brazil colonized only Eucalyptus. The molecular data suggest that the Pisolithus tinctorius isolates analyzed belong to two distinct groups. The data also suggest new guidelines for future investigations on the taxonomy
and systematic of this important fungus species. Furthermore, these results support future experiments aimed at the selection
and development of improved isolates of P. tinctorius.
Accepted: 3 October 1997 相似文献
5.
6.
M. Pillay E. Ogundiwin D. C. Nwakanma G. Ude A. Tenkouano 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(6-7):965-970
The genetic diversity and phylogenetic relationships of 29 East African highland banana (Musa spp.) cultivars and two outgroup taxa, M. acuminata Calcutta 4 and Agbagba were surveyed by RAPD analysis. A genetic similarity matrix was established based on the presence
or absence of polymorphic amplified fragments. Phylogenetic relationships were determined by UPGMA cluster analysis. RAPDs
showed that the highland bananas are closely related with a narrow genetic base. Nevertheless, there were sufficient RAPD
polymorphisms that were collectively useful in distinguishing the cultivars. The dendrogram was divisible into a major cluster
composed of all the AAA highland banana cultivars and Agbagba (AAB) and a minor cluster consisting of Kisubi (AB), Kamaramasenge
(AB) and Calcutta 4 (AA). Several subgroups are recognized within the major cluster. RAPD data did not separate beer and cooking
banana cultivars. Our study showed that RAPD markers can readily dissect genetic differences between the closely related highland
bananas and provide a basis for the selection of parents for improvement of this germplasm.
Received: 28 June 2000 / Accepted: 1 August 2000 相似文献
7.
Genetic diversity and relationships detected by isozyme and RAPD analysis of crop and wild species of Amaranthus 总被引:3,自引:0,他引:3
K. F. Chan M. Sun 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(5-6):865-873
Genetic diversity and relationships of 23 cultivated and wild Amaranthus species were examined using both isozyme and RAPD markers. A total of 30 loci encoding 15 enzymes were resolved, and all
were polymorphic at the interspecific level. High levels of inter-accessional genetic diversity were found within species,
but genetic uniformity was observed within most accessions. In the cultivated grain amaranths (A. caudatus, A. cruentus, and A. hypochondriacus), the mean value of HT was 0.094, HS was 0.003, and GST was 0.977 at the species level. The corresponding values in their putative wild progenitors (A. hybridus, A. powellii, and A. quitensis) were 0.135, 0.004, and 0.963, respectively. More than 600 RAPD fragments were generated with 27 arbitrary 10-base primers.
On average, 39.9% of the RAPD fragments were polymorphic among accessions within each crop species; a similar level of polymorphism
(42.8%) was present in the putative progenitors, but much higher levels of polymorphism were found in vegetable (51%) and
other wild species (69.5%). The evolutionary relationships between grain amaranths and their putative ancestors were investigated,
and both the RAPD and isozyme data sets supported a monophyletic origin of grain amaranths, with A. hybridus as the common ancestor. A complementary approach using information from both isozymes and RAPDs was shown to generate more
accurate estimates of genetic diversity, and of relationships within and among crop species and their wild relatives, than
either data set alone.
Received: 13 March 1997/Accepted: 6 May 1997 相似文献
8.
The use of microsatellites for detecting DNA polymorphism, genotype identification and genetic diversity in wheat 总被引:35,自引:0,他引:35
M. Prasad R. K. Varshney J. K. Roy H. S. Balyan P. K. Gupta 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(3-4):584-592
A set of 20 wheat microsatellite markers was used with 55 elite wheat genotypes to examine their utility (1) in detecting
DNA polymorphism, (2)in the identifying genotypes and (3) in estimating genetic diversity among wheat genotypes. The 55 elite
genotypes of wheat used in this study originated in 29 countries representing six continents. A total of 155 alleles were
detected at 21 loci using the above microsatellite primer pairs (only 1 primer amplified 2 loci; all other primers amplified
1 locus each). Of the 20 primers amplifying 21 loci, 17 primers and their corresponding 18 loci were assigned to 13 different
chromosomes (6 chromosomes of the A genome, 5 chromosomes of the B genome and 2 chromosomes of the D genome). The number of
alleles per locus ranged from 1 to 13, with an average of 7.4 alleles per locus. The values of average polymorphic information
content (PIC) and the marker index (MI) for these markers were estimated to be 0.71 and 0.70, respectively. The (GT)n microsatellites were found to be the most polymorphic. The genetic similarity (GS) coefficient for all possible 1485 pairs
of genotypes ranged from 0.05 to 0.88 with an average of 0.23. The dendrogram, prepared on the basis of similarity matrix
using the UPGMA algorithm, delineated the above genotypes into two major clusters (I and II), each with two subclusters (Ia,
Ib and IIa, IIb). One of these subclusters (Ib) consisted of a solitary genotype (E3111) from Portugal, so that it was unique
and diverse with respect to all other genotypes belonging to cluster I and placed in subcluster Ia. Using a set of only 12
primer pairs, we were able to distinguish a maximum of 48 of the above 55 wheat genotypes. The results demonstrate the utility
of microsatellite markers for detecting polymorphism leading to genotype identification and for estimating genetic diversity.
Received: 15 May 1999 / Accepted: 27 July 1999 相似文献
9.
Genetic diversity in wild wheats and goat grass 总被引:4,自引:0,他引:4
S. G. Hegde J. Valkoun J. G. Waines 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,101(1-2):309-316
The genetic structure of 35 populations of wild relatives of cultivated wheats, all collected in Syria and Lebanon, was assessed
using ten isozymes. The populations consisted of diploid goat grass, Aegilops speltoides, diploid wild wheats, Triticum monococcum spp. aegilopoides and T. urartu, and tetraploid wild wheat, T. turgidum ssp. dicoccoides. The majority of the populations were polymorphic (P=0–70%) having low within-population mean genetic diversity (Hep=0.05–0.10) and relatively high within-species genetic diversity (Hes=0.14–0.31). The linkage between loci did not seem to be one of the causes for the observed polymorphism. All four species
showed significant inbreeding at both the population (0.31–0.64) and species (0.77–0.96) levels, and the extent of inbreeding
did not correlate with mating systems. Despite their apparent common ecological and evolutionary history, between-population
or between-species level genetic identity was low (I=0.43–0.86). Among the diploid species, populations of Ae. speltoides clustered distinctly from those overlapping clusters of T. monococcum ssp. aegilopoides and T. urartu. The tetraploid species T. turgidum ssp. dicoccoides had relatively less genetic diversity (Hes=0.14) and was highly homozygous (F=0.96). The results suggest that these wild progenitors of cultivated wheats have undergone
extensive local differentiation and inbreeding. We discuss the implications of our results on the management of wild wheat
and goat grass populations.
Received: 12 September 1999 / Accepted: 10 November 1999 相似文献
10.
11.
A. Singh M. S. Negi J. Rajagopal S. Bhatia U. K. Tomar P. S. Srivastava M. Lakshmikumaran 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(1-2):272-279
Genetic diversity was estimated in 37 neem accessions from different eco-geographic regions of India and four exotic lines
from Thailand using AFLP markers. Seven AFLP selective primer combinations generated a total of 422 amplification products.
The average number of scorable fragments was 60 per experiment, and a high degree (69.8%) of polymorphism was obtained per
assay with values ranging from 58% to 83.8%. Several rare and accession-specific bands were identified which could be effectively
used to distinguish the different genotypes. Genetic relationships within the accessions were evaluated by generating a similarity
matrix based on the Jaccard index. The phenetic dendrogram generated by UPGMA as well as principal correspondence analysis
separated the 37 Indian genotypes from the four Thai lines. The cluster analysis indicated that neem germplasm within India
constitutes a broad genetic base with the values of genetic similarity coefficient ranging from 0.74 to 0.93. Also, the Indian
genotypes were more dispersed on the principal correspondence plot, indicating a wide genetic base. The four lines from Thailand,
on the other hand, formed a narrow genetic base with similarity coefficients ranging from 0.88 to 0.92. The lowest genetic
similarity coefficient value (0.47) was observed between an Indian and an exotic genotype. The level of genetic variation
detected within the neem accessions with AFLP analysis suggests that it is an efficient marker technology for delineating
genetic relationships amongst genotypes and estimating genetic diversity, thereby enabling the formulation of appropriate
strategies for conservation and tree improvement programs.
Received: 20 October 1998 / Accepted: 28 November 1998 相似文献
12.
Molecular marker diversity among current and historical maize inbreds 总被引:25,自引:0,他引:25
H. Lu R. Bernardo 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,103(4):613-617
Advanced-cycle pedigree breeding has caused maize (Zea mays L.) inbreds to become more-elite but more-narrow genetically. Our objectives were to evaluate the genetic distance among
current and historical maize inbreds, and to estimate how much genetic diversity has been lost among current inbreds. We selected
eight maize inbreds (B14, B37, B73, B84, Mo17, C103, Oh43 and H99) that largely represented the genetic background of current
elite inbreds in the U.S. seed industry. A total of 32 other inbreds represented historical inbreds that were once important
in maize breeding. Cluster analysis of the inbreds, using data for 83 SSR marker loci, agreed well with pedigree information.
Inbreds from Iowa Stiff Stalk Synthetic (BSSS), Reid Yellow Dent, and Lancaster clustered into separate groups with only few
exceptions. The average number of alleles per locus was 4.9 among all 40 inbreds and 3.2 among the eight current inbreds.
The reduction in the number of alleles per locus was not solely due to sample size. The average genetic distance (D
ij
) was 0.65 among the eight current inbreds, 0.67 among the 32 historical inbreds, and 0.67 among all 40 inbreds. These differences
were statistically insignificant. We conclude that genetic diversity among current inbreds has been reduced at the gene level
but not at the population level. Hybrid breeding in maize maintained, rather than decreased, genetic diversity, at least during
the initial subdivision of inbreds into BSSS and non-BSSS heterotic groups. We speculate, however, that exploiting other germplasm
sources is necessary for sustaining long-term breeding progress in maize.
Received: 21 August 2000 / Accepted: 5 January 2001 相似文献
13.
D. K. Santra G. Singh W. J. Kaiser V. S. Gupta P. K. Ranjekar F. J. Muehlbauer 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(5):676-682
Genetic diversity in Ascochyta rabiei (Pass.) Labr., the causative agent of ascochyta blight of chickpea, was determined using 37 Indian, five American (USA),
three Syrian, and two Pakistani isolates. A total of 48 polymorphic RAPD markers were scored for each isolate and the data
used for cluster analysis. Most of the isolates clustered in the dendrogram essentially according to geographic origin. Based
on the two major clusters A and B, Indian isolates were grouped into two categories, type-A and type-B. Isolates of A. rabiei within the Punjab state were more diverse than isolates from other states in northwestern India. A DNA marker (ubc7561.6 kb), specific to Indian isolates was identified. This is the first report of a molecular diversity analysis of Indian isolates
of A. rabiei. The information may assist Indian chickpea breeders in the proper deployment of blight-resistant cultivars and in disease
management.
Received: 25 April 2000 / Accepted: 11 July 2000 相似文献
14.
小麦耐盐种质遗传多样性的RAPD分析 总被引:8,自引:0,他引:8
选用22个引物对24份小麦耐盐种质进行RAPD分析,共产生200条扩增片段,多态性片段数为172条,扩增片段的多态性百分率为86%,利用NYSTS软件根据Jaccard系统分析RAPD结果,并按UPGMA类平均法进行聚类。24份材料相似系数在0.21 ̄0.97之间,其中含有多枝赖草、黑麦和偃麦草等外源染色体的多174、WR830和南前127被分别在3个独立的组,多174和南前127的亲关系最远,相 相似文献
15.
Microsatellite polymorphism in natural populations of wild emmer wheat,Triticum dicoccoides,in Israel 总被引:5,自引:0,他引:5
Fahima T Röder MS Wendehake K Kirzhner VM Nevo E 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2002,104(1):17-29
Diversity in 20 microsatellite loci of wild emmer wheat, Triticum dicoccoides, was examined in 15 populations (135 genotypes) representing a wide range of ecological conditions of soil, temperature, and
water availability, in Israel and Turkey. An extensive amount of diversity at microsatellite loci was observed despite the
predominantly selfing nature of this plant species. The 20 Gatersleben wheat microsatellites (GWM), representing 13 chromosomes
of genomes A and B of wheat, revealed a total of 364 alleles, with an average of 18 alleles per GWM marker (range: 5–26).
The proportion of polymorphic loci per population averaged 0.90 (range: 0.45– 1.00); genic diversity, He, averaged 0.50 (range 0.094– 0.736); and Shannon’s information index averaged 0.84 (range 0.166–1.307). The coefficients
of genetic distance between populations were high and averaged D=1.862 (range 0.876–3.320), an indication of sharp genetic divergence over short distances. Interpopulation genetic distances
showed no association with geographic distance between the population sites of origin, which ruled out a simple isolation
by distance model. Genetic dissimilarity values between genotypes were used to produce a dendrogram of the relationships among
wild wheat populations by the unweighted pair-group method with arithmetic averages (UPGMA). The results showed that all the
wild emmer wheat populations could be distinguished. Microsatellite analysis was found to be highly effective in distinguishing
genotypes of T. dicoccoides, originating from diverse ecogeographical sites in Israel and Turkey, with 88% of the 135 genotypes correctly classified into
sites of origin by discriminant analysis. Our present microsatellite results are non-random and in agreement with the previously
obtained allozyme and RAPD patterns, although the genetic-diversity values obtained with microsatellites are much higher.
Significant correlates of microsatellite markers with various climatic and soil factors suggest that, as in allozymes and
RAPDs, natural selection causes adaptive microsatellite ecogeographical differentiation, not only in coding, but most importantly
in non-coding genomic regions. Hence, the concept of ”junk DNA” needs to be replaced by at least partly regulatory DNA. The
obtained results suggest that microsatellite markers are useful for the estimation of genetic diversity in natural populations
of T. dicoccoides and for the tagging of agronomically important traits derived from wild emmer wheat.
Received: 27 February 2001 / Accepted: 22 March 2001 相似文献
16.
S. G. Nebauer L. del Castillo-Agudo J. Segura 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(8):1209-1216
RAPD markers were used to study inter-specific variation among six species of the genus Digitalis: D. obscura, D. lanata, D. grandiflora, D. purpurea, D. thapsi and D. dubia, and the hybrid D. excelsior (D. purpurea×D. grandiflora). A total of 91 highly reproducible bands amplified with four arbitrarily chosen decamer primers were obtained. Homology
of the co-emigrating RAPD markers was tested by blot hybridisation and sequencing of selected bands. The application of a
range of statistical approaches for RAPD data analysis, including distance and parsimony methods, family clustering and the
analysis of molecular variance (AMOVA), indicated that these molecular markers were taxonomically informative in Digitalis. The species relationships revealed were fully consistent with those previously obtained using morphological affinities.
The hybrid D. excelsior seems to have stronger affinity to the section Digitalis than to Grandiflorae. This is the first known report of the application of RAPD markers for the study of genetic relationships among species of
the genus Digitalis.
Received: 20 October 1999 / Accepted: 9 November 1999 相似文献
17.
W. Cao G. R. Hughes H. Ma Z. Dong 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(4):551-554
The development of Septoria nodorum blotch-resistant cultivars has become a high priority objective for durum wheat breeding programs. Marker-assisted selection
enables breeders to improve selection efficiency. In order to develop markers for resistance to Septoria nodorum blotch, a set of F5 recombinant inbred lines, derived from the crosses Sceptre/3–6, Sceptre/S9–10 and Sceptre/S12–1, was developed based on the
F2-derived family method. Two RAPD markers, designated UBC521650 and RC37510, were detected by bulked segregant analysis and located approximately 15 and 13.1 centiMorgans (cM) from the resistance gene
snbTM, respectively. A SCAR marker was also successfully developed for marker-assisted selection in breeding programs based on
the sequence of the RAPD marker UBC521650. This is the first report of DNA-based markers linked to resistance for Septoria nodorum blotch in durum wheat.
Received: 8 March 2000 / Accepted: 25 June 2000 相似文献
18.
Genetic diversity and relationships of diploid and tetraploid cottons revealed using AFLP 总被引:17,自引:0,他引:17
A. M. Abdalla O. U. K. Reddy K. M. El-Zik A. E. Pepper 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(2-3):222-229
Gossypium species (± 49) represent a vast resource of genetic diversity for the improvement of cultivated cotton. To determine intra-
and inter-specific genetic relationships within a diverse collection of Gossypium taxa, we employed 16 AFLP primer combinations on three diploid species, Gossypium herbaceum L. (A1), Gossypium arboreum L. (A2) and Gossypium raimondii Ulbrich (D5), and 26 AD allotetraploid accessions (Gossypium barbadense L. and Gossypium hirsutum L.). A total of 1180 major AFLP bands were observed; 368 of these (31%) were polymorphic. Genetic similarities among all
taxa ranged from 0.21 (between the diploid species G. arboreum and G. raimondii) up to 0.89 (within G. barbadense). Phenetic trees based on genetic similarities (UPGMA, N-J) were consistent with known taxonomic relationships. In some cases,
well-supported phylogenetic relationships, as well as evidence of genetic reticulation, could also be inferred. UPGMA trees
and principal coordinate analysis based on genetic similarity matrices were used to identify genetically distinct cultivars
that are potentially important sources of germplasm for cotton improvement, particularly of fiber quality traits. We show
that AFLP is useful for estimating genetic relationships across a wide range of taxonomic levels, and for analyzing the evolutionary
and historical development of cotton cultivars at the genomic level.
Received: 17 January 2000 / Accepted: 4 May 2000 相似文献
19.
Genetic diversity of Cryptomeria japonica using co-dominant DNA markers based on sequenced-tagged sites 总被引:3,自引:0,他引:3
Y. Tsumura N. Tomaru 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(3-4):396-404
We have investigated the genetic diversity of 11 natural populations of C. japonica using 13 polymorphic STS markers. The average unbiased heterozygosities (H
e
), the average number of alleles per locus (N
a
) and the proportion of polymorphic loci (Pl) were 0.281, 1.93 and 76.92%, respectively. Coefficients of linkage disequilibrium were calculated, and no significant deviation
was found except in four combinations – which might have occurred by chance alone. The fixation index (F
IS
) for 3 loci showed statistically significant values at the 1% level. The genetic differentiation between populations was
only 0.047, and there were no clear geographical tendencies in the allele frequencies or the heterozygosities among populations.
Consequently, the results from STS-based co-dominant DNA marker analysis were very similar to those from a previous allozyme
study. However, the resolution of the technique is greater than allozyme analysis because many loci with high heterozygosities
can be evaluated, and it is very simple. Therefore, the STS-based marker approach is very useful and convenient for population
genetics and genome mapping of C. japonica.
Received: 18 July 1998 / Accepted: 13 August 1998 相似文献
20.
Soleimani VD Baum BR Johnson DA 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2002,104(2-3):350-357
A substantial amount of between and within cultivar genetic variation was detected in all the 13 registered modern Canadian
durum wheat (Triticum turgidum L. ssp. durum (Desf.) Husn.) cultivars based upon amplified restriction fragment polymorphism (AFLP). Of the approximately 950 detected
AFLP markers, only 89 were polymorphic, with 41 between cultivars whereas the remaining 48 showed polymorphism within at least
one cultivar. The ancestry of Canadian durum wheat cultivars was traced back to 125 cultivars, selections, and breeding lines
including 17 landraces. Mean pair-wise genetic distance based on the kinship coefficient was 0.76. On the other hand, AFLP-based
mean pair-wise genetic distance was 0.40. Even though there was a large difference between the means of the two diversity
measures, a moderate positive correlation (r=0.457, p<0.002) was detected between the two distance matrices. Cluster analysis with the entire AFLP data divided all cultivars into
three major groups reflecting their breeding origins. One group contained ’Pelissier’ alone, which was a selection from a
landrace introduced into the US from Algeria. On the other hand such groupings among cultivars were not evident when KIN was
used for genetic diversity measures instead. The level of genetic variation among individuals within a cultivar at the breeders’
seed level was estimated based on an inter-haplotypic distance matrix derived from the AFLP data. We found that the level
of genetic variation within the most-developed cultivars is fairly substantial despite rigorous selection pressure aimed at
cultivar purity in breeding programs. Comparison of AFLP and pedigree-based genetic diversity estimates in crop species such
as durum wheat can provide important information for plant improvement.
Received: 26 January 2001 / Accepted: 31 May 2001 相似文献