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1.
Local cultivars adapted to specific environmental conditions are the chief source of seed for farmers in Ethiopia and deserve
research priority. The aim of this study was, therefore, to determine the genetic relationships between different barley landraces,
from north Shewa in Ethiopia so as to differentiate genotypes known by different local names and facilitate their conservation
and use in breeding new varieties. Five AFLP primer combinations were analyzed for 19 barley landraces and five malting varieties.
The number of scoreable fragments amplified by each AFLP primer combination varied from 49 to 118 with an average of 84.5
and polymorphic fragments for each primer combination varied from 27 to 77 with an average of 58.5. The average percent polymorphism
was 69.9% with values ranging from 55.1% to 75.8%. Cluster analysis placed the accessions and malting varieties into one main
group while all the farmers’ cultivars, with the exception of two, were in the other main group. It was shown that sampling
of germplasm at a given locality might not represent the whole array of genetic variability of locally grown famers’ cultivars.
A comprehensive study of all the farmers’ barley cultivars, grown in different parts of Ethiopia, is required to maximize
the efforts of germplasm conservation and utilization in national and regional breeding programs. 相似文献
2.
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
3.
Genetic diversity analysis in sorghum germplasm as estimated by AFLP, SSR and morpho-agronomical markers 总被引:4,自引:0,他引:4
Nemera Geleta Maryke T. Labuschagne Chris D. Viljoen 《Biodiversity and Conservation》2006,15(10):3251-3265
A comparison of the different methods of the estimation of genetic diversity is important to evaluate their utility as a tool
in germplasm conservation and plant breeding. Amplified fragment length polymorphism (AFLP), microsatellites or SSR and morphological
traits markers were used to evaluate 45 sorghum germplasm for genetic diversity assessment and discrimination power. The mean
polymorphism information content (PIC) values were 0.65 (AFLPs) and 0.46 (SSRs). The average pairwise genetic distance estimates
were 0.57 (morphological traits), 0.62 (AFLPs) and 0.60 (SSRs) markers data sets. The Shannon diversity index was higher for
morphological traits (0.678) than AFLP (0.487) and SSR (0.539). The correlation coefficients obtained by the Mantel matrix
correspondence test, which was used to compare the cophenetic matrices for the different markers, showed that estimated values
of genetic relationship given for AFLP and SSR markers, as well as for morphological and SSR markers were significantly related
(p <0.001). However, morphological and AFLP data showed non-significant correlation (p >0.05). Both data sets from AFLP and SSR allowed all accessions to be uniquely identified; two accessions could not be distinguished
by the morphological data. In summary, AFLP and SSR markers proved to be efficient tools in assessing the genetic variability
among sorghum genotypes. The patterns of variation appeared to be consistent for the three marker systems, and they can be
used for designing breeding programmes, conservation of germplasm and management of sorghum genetic resources. 相似文献
4.
A parentage study of closely related Ukrainian wine grape varieties using microsatellite markers 总被引:1,自引:0,他引:1
S. Goryslavets V. Risovanna R. Bacilieri J. -F. Hausman M. Heuertz 《Cytology and Genetics》2010,44(2):95-102
Four bred grapevine varieties released for commercial cultivation in Ukraine, namely ‘Antey Magarachskii’, ‘Rubinovyi Magaracha’,
‘Granatovyi Magaracha’ and ‘Rubin Golodrigi’, and their putative parental forms were genotyped using six microsatellite loci.
Genotypes were compared with breeding records to verify genetic relationships among varieties. Results of the analysis confirmed
four of six parent-offspring relationships. Results of the analysis allow to assume that genotype ‘Seyve Villard 20347’ is
the direct parent of ‘Antey Magarachskii’ instead of its grandparent. The first-studied accession believed to be that of ‘Granatovyi
Magaracha’ was identified as impurity. In order to verify the parentage of ‘Granatovyi Magaracha’, rest accessions of that
variety and its putative parent ‘Antey Magarachskii’ were additionally genotyped at 13 nuclear loci and at three chloroplast
loci. The parent-offspring relationship was confirmed, as all ‘Granatovyi Magaracha’ accessions had a common allele with the
parent variety ‘Antey Magarachskii’ at each locus and the same chlorotype A. Different ‘Granatovyi Magaracha’ accessions could
have been obtained via vegetative propagation of two seedlings which arose from one crossing. 相似文献
5.
Heckenberger Martin van der Voort Jeroen Rouppe Peleman Johan Bohn Martin 《Molecular breeding : new strategies in plant improvement》2003,12(2):97-106
Accuracy and reproducibility of genetic distances (GDs) based on molecular markers are crucial issues for identification of essentially derived varieties (EDVs). Our objectives were to investigate (1) the amount of variation for amplified fragment length polymorphism (AFLP) markers found among different accessions within maize inbreds and doubled haploid (DH) lines, (2) the proportion attributable to genetic and technical components and marker system specific sources, (3) its effect on GDs between maize lines and implications for identification of EDVs, and (4) the comparison to published SSR data from the same plant materials. Two to five accessions from nine inbred lines and five DH lines were taken from different sources of maintenance breeding or drawn as independent samples from the same seed lot. Each of the 41 accessions was genotyped with 20 AFLP primer combinations revealing 988 AFLP markers. Map positions were available for 605 AFLPs covering all maize chromosomes. On average, six (0.6%) AFLP bands were polymorphic between different accessions of the same line. GDs between two accessions of the same line averaged 0.013 for inbreds and 0.006 for DH lines. The correlation of GDs based on AFLPs and SSRs was tight (r = 0.97**) across all 946 pairs of accessions but decreased (r = 0.55**) for 43 pairs of accessions originating from the same line. On the basis of our results, we recommend specific EDV thresholds for marker systems with different degree of polymorphism. In addition, precautions should be taken to warrant a high level of homogeneity for DNA markers within maize lines before applying for plant variety protection. 相似文献
6.
In this study, the genetic diversity of ‘Ubá’ mango trees cultivated at the Zona da Mata of Minas Gerais State, Brazil, was
assessed, to identify whether there is variability in the plants grown in the region, justifying the mass selection as a breeding
method. We used 102 accessions. Leaves were collected for extraction of genomic DNA, which was amplified with nine ISSR primers.
The data obtained by the analysis of electrophoretic patterns were arranged in a binary matrix, considering 0 for the absence
and 1 for the presence of bands. Based on these data, we performed the analysis of genetic dissimilarity and carried out the
cluster analysis by the methods of Tocher and graphical dispersion. The most similar accessions are 144 and 150, both coming
from Ubá, while the most divergent ones are 29 and 97, from Visconde do Rio Branco. The grouping by the Tocher method separated
the accessions into six groups, 94.1% of which were allocated in the first group and showed that there is no separation of
accessions depending on the sampling sites. The 3D scatter plot reinforces this conclusion. There is genetic variability among
the accessions of ‘Ubá’ mango tree evaluated. Therefore, it is possible to make mass selection in open-pollinated populations. 相似文献
7.
The sacred lotus (Nelumbo nucifera Gaertn.) is an aquatic plant of economic and ornamental importance in China. In this study, we developed twenty novel sacred
lotus SSR markers, and used AFLP and SSR markers to investigate the genetic diversity and genetic relationships among 58 accessions
of N.
nucifera including 15 seed lotus, 12 rhizome lotus, 24 flower lotus and 7 wild lotus. Our results showed that sacred lotus exhibited
a low level of genetic diversity, which may attribute to asexual reproduction and long-term artificial selection. A dendrogram
based on both AFLP and SSR clustering data showed that: (1) the seed lotus accessions and rhizome lotus accessions were distinctly
clustered into different groups, which indicated the significant genetic differentiation between them. This may be attributed
to the two modes of reproduction and lack of genetic exchange; (2) the accessions of Thailand wild lotus were separated from
other wild lotus accessions. This implied that the Thailand lotus might be genetically differentiated from other wild lotuses.
In addition, Mantel test conducted gave highly significant correlation between AFLP-SSR data and each of the AFLP and SSR
ones, with the values of r = 0.941 and r = 0.879, respectively, indicating the higher efficiency of the combination of these techniques (AFLP and SSR) in estimation
and validation of the genetic diversity among the accession of sacred lotus. This knowledge of the genetic diversity and genetic
relatedness of N. nucifera is potentially useful to improve the current strategies in breeding and germplasm conservation to enhance the ornamental
and economic value of sacred lotus. 相似文献
8.
A. R. Purba J. L. Noyer L. Baudouin X. Perrier S. Hamon P. J. L. Lagoda 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,101(5-6):956-961
Oil palm (Elaeis guineensis Jacq.) plays an important economic role in some countries of Southeast Asia like Indonesia, which is the world’s second producer
of palm and palm kernel oil. The quality improvement of planting material needs a better understanding of the genetic relationships
between genotypes from different populations used in the breeding programmes. In this study, 48 parents, representative of
four populations used in Indonesian Oil Palm Research Institute (IOPRI) breeding programmes, were analysed with five selected
AFLP primer pairs and four isoenzymatic systems. One hundred and fifty eight scorable band levels were generated of which
96 (61%) were polymorphic. AFLP allowed us to identify off–type descendants which were excluded from analysis. The use of
unbiased Rogers distance clearly separated the four studied populations. The Neighbor-Joining method re-groups two African
populations which are known as originating from different regions. Nevertheless, the variability revealed is in accordance
with oil palm breeders’ knowledge. The results obtained with AFLP showed that the crosses among the African sub-population,
which is excluded in oil palm reciprocal recurrent selection (RRS) breeding programmes, may be more interesting than the crosses
between the African and the Deli populations.
Received: 9 August 1999 / Accepted: 28 February 2000 相似文献
9.
M. A. Filjushin O. A. Kholda E. Z. Kochieva N. N. Ryzhova 《Russian Journal of Genetics》2011,47(4):492-496
The results of the AFLP analysis of 16 leek (Allium porrum) accessions and related species of the sections of the genus Allium are presented. Restriction enzymes and primer combinations for the identification of the genotypes of the A. porrum accessions were chosen. As a result, 265 polymorphic AFLP fragments were amplified for 25 analyzed genotypes, and specific
spectra of DNA fragments were obtained for each accession. A total of 24 fragments specific for the A. porrum genome was detected, of which only two characterized the genotypes of individual accessions. A wide range of genetic diversity
(0.11–0.32) was revealed for the A. porrum varieties and lines used in the analysis. The highest level of similarity in the analyzed set of accessions was found between
A. porrum and sand leek (A. scorodoprasum). 相似文献
10.
Carthamus tinctorius (2n = 2x = 24), commonly known as safflower, is widely cultivated in agricultural production systems of Asia, Europe, Australia, and
the Americas as a source of high quality vegetable and industrial oil. Twenty-two RAPD primers, 18 SSR primers, and 10 AFLP
primer combinations were used to assess: (1) the genetic diversity of 85 accessions (originating from 24 countries) representing
global germplasm variability of safflower and (2) the interrelationships among safflower ‘centers of similarity’ or ‘regional
gene pools’ proposed earlier. The RAPD and SSR primers and AFLP primer combinations revealed 57.6, 68.0, and 71.2% polymorphism,
respectively, among 111, 72, and 330 genetic loci amplified from the accessions. The sum of effective number of alleles (66.44),
resolving power (59.16), and marker index (51.3) explicitly revealed the relative superiority of AFLP as a marker system in
uncovering variation in safflower. Overall, AFLP markers could recognize ‘centers of similarity’ or ‘regional gene pools’.
Analysis of molecular variance and Shannon’s information index provided corroborating evidences for the present and previous
studies that concluded fragmentation of safflower gene pool into many gene pools. Divergent directional selection is likely
to have played an important role in shaping the diversity. From the practical applications standpoint, the diversity of Iran–Afghanistan
gene pool is very high, equivalent to the total diversity of the species. The Far East gene pool is the least diverse. The
present comprehensive input, first of its own kind in safflower, will assist marker based improvement programmes in the crop. 相似文献
11.
Leymus chinensis (Trin.) Tzvel is a perennial grass in the tribe Gramineae and important forage in Northern China. Knowledge of its genetic
diversity is a prerequisite for using modern breeding techniques. Amplified fragment length polymorphism (AFLP) was first
used to evaluate the genetic relationship among and within three ecotypes. Distinct clusters were produced based on AFLP markers.
All accessions from the same ecotype were grouped in a cluster except accessions 6. According to AFLP profile ecotype-specific bands differ from each other. The genetic differentiation within the ecotype
of the species was much smaller than that among ecotypes. Self-incompatibility in this species contributes to evident genetic
differentiation together with environment. These results indicate that ecotypes were distinguished visually similarly to genetic
variation.
Published in Russian in Fiziologiya Rastenii, 2006, Vol. 53, No. 5, pp. 764–770.
The text was submitted by the authors in English. 相似文献
12.
Roldán-Ruiz I. Dendauw J. Van Bockstaele E. Depicker A. De Loose M. 《Molecular breeding : new strategies in plant improvement》2000,6(2):125-134
An evaluation was performed of the potential use of AFLP markers to reveal polymorphisms among Lolium perenne plants with different degrees of kinship. Radioactive and fluorescent detection techniques were applied. The use of a fluorescent detection approach contributed greatly to the speed and ease of conducting and interpreting the AFLP patterns. The great discriminative power of AFLP markers and their capacity to represent genetic relationships among ryegrass plants was shown. Despite the high polymorphic value of the AFLP markers, standard statistical tests could not differentiate between two gene pools derived from different breeding programmes. It proved also impossible to correlate fodder and turf phenotypes with AFLP distance data. A very important point revealed by our data is the high degree of genetic diversity within commercial ryegrass varieties. Our findings are relevant to any outcrossing crop with a breeding strategy based on the production of synthetic populations. 相似文献
13.
Cassava bacterial blight (CBB) is caused by Xanthomonas axonopodis pv. manihotis (Xam). Resistance is found in Manihot esculenta and, in addition, has been introgressed from a wild relative, M. glaziovii. The resistance is thought to be polygenic and additively inherited. Ninety-three varieties of M. esculenta (Crantz) were assessed by AFLPs for genetic diversity and for resistance to CBB. AFLP analysis was performed using two primer combinations and a 79.2% level of polymorphism was found. The phenogram obtained showed between 74% and 96% genetic similarity among all cassava accessions analysed. The analysis permitted the unique identification of each individual. Two Xam strains were used for resistance screening. Variation in the reaction of cassava varieties to Xam strains was observed for all plant accessions. The correlation of resistance to both strains, had a coefficient of 0.53, suggesting the independence of resistance to each strain. Multiple correspondence analysis showed a random distribution of the resistance/susceptibility response with respect to overall genetic diversity as measured by AFLP analysis. A total heterozygosity index was calculated to determine the diversity within clusters as well as among them. Our results demonstrate that resistance to CBB is broadly distributed in cassava germplasm and that AFLP analysis is an effective and efficient means of providing quantitative estimates of genetic similarities among cassava accessions. 相似文献
14.
The results of the AFLP analysis of 16 leek (Allium porrum) accessions and related species of the sections of the genus Allium are presented. Restriction enzymes and primer combinations for the identification of the genotypes of the A. porrum accessions were chosen. As a result, 265 polymorphic AFLP fragments were amplified for 25 analyzed genotypes, and specific spectra of DNA fragments were obtained for each accession. A total of 24 fragments specific for the A. porrum genome was detected, of which only two characterized the genotypes of individual accessions. A wide range of genetic diversity (0.11-0.32) was revealed for the A. porrum varieties and lines used in the analysis. The highest level of similarity in the analyzed set of accessions was found between A. porrum and sand leek (A. scorodoprasum). 相似文献
15.
Furini A Wunder J 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,108(2):197-208
A total of 94 Solanum accessions, including eggplants and related species, were morphologically characterized based on greenhouse observations, and molecularly analysed by the AFLP technique. Morphological parameters were helpful in assessing similarities or differences among accessions, and molecular data were used to support morphological conclusions. A dendrogram was computed based on the Dice genetic distances using the neighbour-joining method. The analysis was efficient in the assignment of a species name for eight out of nine accessions that were not previously classified, and revealed that 14 further accessions were misnamed in the collection originally received. The results indicate that the taxonomy of Solanum sections and subgenera including several species should be reconsidered. The AFLP technique was revealed as an efficient tool in determining genetic relationships among species. In general, morphological observations were consistent with molecular data, indicating that both approaches complemented to define the phylogenetic status of a large genus like Solanum. In terms of eggplant breeding, the molecular analysis of the Melongena complex, and of the other sections of the subgenus Leptostemonum, establishes useful germplasm relationships in the gene pool available for the genetic improvement of the cultivated species. The results we have provided highlight an urgent necessity to include molecular parameters in handling and characterizing the genebank-deposited germplasm related to cultivated crops.Communicated by F. Salamini 相似文献
16.
M. Tucak S. Popović T. Čupić S. Grljušić V. Meglič Z. Jurković 《Russian Journal of Genetics》2010,46(11):1314-1319
Information on genetic diversity and germplasm characterization is essential for successful crop improvement. Diverse data
sets (pedigree, morphological, biochemical, DNA based-markers) are employed in various aspects of plant analysis. The objective
of this study was to determine the efficiency of phenotypic and RAPD markers in diversity assessment of ten alfalfa (Medicago spp.) accessions from Europe, North America and Australia. Field experiment was designed as a randomised complete block with
three replications over two consecutive years (2004, 2005) at one location. Twelve morpho-agronomic traits were recorded on
50 plants per each accession. Genomic DNA’s from 16–20 randomly selected individual plants per accession were used for RAPD
analysis. Six primers selected in this study generated a total of 93 polymorphic RAPD bands. The number of polymorphic bands
detected per primer ranged from 11 to 20. Genetic distances (GD) among investigated accessions and two-dimensional principal
coordinate analysis (2D PCoA) based on phenotypic and molecular data were obtained. The average GD between (0.283–0.416) and
within (0.247–0.332) accessions based on RAPD data was higher than GD values obtained by morpho-agronomic traits (0.171–0.354
and 0.157–0.261, respectively). 2D PCoA based on GD from RAPD data grouped most of the studied individual plants to four clusters
according to their geographical or taxonomy origin. 2D PCoA based only on morpho-agronomic data did not group plants congruently
to their origin, probably due to a strong environmental influence on studied traits. Our results indicated that the RAPD markers
were effective in assessing genetic diversity within and between studied alfalfa accessions. In addition, the obtained results
suggested that the RAPD markers might be useful for grouping of germplasm with similar genetic background and for pre-screening
of potential heterotic groups in our breeding programme. 相似文献
17.
我国西北春麦区小麦育成品种遗传多样性的AFLP分析 总被引:15,自引:3,他引:15
对我国西北春麦区56份小麦育成品种应用扩增片段长度多态性(Amplified Fragment Length Polmorphics,简称AFLP)分子标记技术进行遗传多样性分析。共用24对引物组合进行扩增,每对引物组合的平均多态性条带为14.7,多态性百分率为24.4,而多态性信息指数PIC范围为0.11~0.44,平均0.22。结合品种的系谱亲缘关系分析,得知依据AFLP数据的类群划分结果与品种的亲缘系谱关系基本一致,表明AFLP技术用于种质鉴定和遗传多样性研究是有效的、可取的;同时。对如何合理应用AFLP数据中的多态性带和共有带进行聚类分析,及如何正确对待小麦核心种质构建中的形态和农艺性状数据与分子数据的问题作了进一步的探讨。仅用多态性谱带产生的相似系数矩阵与用所有扩增谱带产生的相似系数矩阵之间的相关系数r=0.86,表明在利用AFLP进行品种间遗传关系分析时,利用所有扩增产物的信息是必要的;如果仅仅是为了鉴剐品种或压缩样品,完全可以只考虑多态性扩增产物。利用AFLP分子数据和田间数据对56份材料进行主成分分析(PCO),发现用田间数据产生的PCO图,材料之间分散,遗传关系不很明了,进一步压缩样品难度较大;而分子数据产生的PCO图,可将材料分成明显的五类,聚类结果与品种系谱基本相吻合,为进一步压缩样品提供了科学依据。形态数据与分子数据聚类的结果差异较大,相关系数仅为0.310因此,在利用田间数据的基础上,必须兼顾和利用DNA数据,才能保证所建立核心种质的代表性。这也是一条比较科学、经济和可行的途径。 相似文献
18.
Aniko Horvath Audrey Didier Jean Koenig Florence Exbrayat Gilles Charmet François Balfourier 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,119(8):1523-1537
A highly polymorphic core collection of bread wheat and a more narrow-based breeding material, gathered from pedigrees of
seven modern cultivars, was analysed in order to compare genetic diversity indices and linkage disequilibrium (LD) patterns
along the chromosome 3B with microsatellite (SSR) and Diversity Arrays Technology markers. Five ancestral gene pools could
be identified within the core collection, indicating a strong geographical structure (Northwest Europe, Southeast Europe,
CIMMYT–ICARDA group, Asia, Nepal). The breeding material showed a temporal structure, corresponding to different periods of
breeding programmes [old varieties (from old landraces to 1919), semi-modern varieties (1920–1959), modern varieties (1960–2006)].
Basic statistics showed a higher genetic diversity in the core collection than in the breeding material, indicating a stronger
selection pressure in this latter material. More generally, the chromosome 3B had a lower diversity than the whole B-genome.
LD was weak in all studied materials. Amongst geographical groups, the CIMMYT–ICARDA pool presented the longest ranged LD
in contrast to Asian accessions. In the breeding material, LD increased from old cultivars to modern varieties. Genitors of
seven modern cultivars were found to be different; most marker pairs in significant LD were observed amongst genitors of Alexandre
and Koreli varieties, indicating an important inbreeding effect. At low genetic distances (0–5 cM), the breeding material
had higher LD than the core collection, but globally the two materials had similar values in all classes. Marker pairs in
significant LD are generally observed around the centromere in both arms and at distal position on the short arm of the chromosome
3B. 相似文献
19.
Dapeng Zhang Michel Boccara Lambert Motilal David R. Butler Pathmanathan Umaharan Sue Mischke Lyndel Meinhardt 《Conservation Genetics》2008,9(2):327-337
Utilization of germplasm for crop improvement is often hampered by absence of information regarding origin, genetic identity
and genealogical relationships of germplasm groups or populations. Molecular marker technology offers an efficient tool to
verify or reconstruct passport data. Using a high-throughput genotyping system with 15 microsatellite loci, we fingerprinted
482 accessions in 48 putative half-sib families of Refractario cacao (a group of germplasm collected from nine farms in Ecuador).
Based on the multilocus profiles, a Bayesian method for individual assignment was applied to verify membership in each half-sib
family. Multivariate statistical analysis showed that the Refractario genetic profile was different from other groups tested,
except for the “Nacional” cacao from the coastal valley of Ecuador. Hierarchical partitioning of genetic variance in the Refractario
cacao showed that 76% of the variation was contributed by intra-family difference, whereas the inter-family and inter-farm
difference accounted for 15 and 9% of total variance, respectively. All three sources of variation were highly significant
(P < 0.01). Cluster and Principal Coordinates Analyses revealed a population sub-structure in Refractario, which was also highly
heterozygous, suggesting hybridization derived from Nacional cacao and multiple other parental varieties, which all shared
a similar genetic background. The improved understanding of identities and structure in Refractario cacao will contribute
to more efficient conservation and use of this germplasm group in cacao breeding. 相似文献
20.
QTL mapping of aroma compounds analysed by headspace solid-phase microextraction gas chromatography in the apple progeny ‘Discovery’ × ‘Prima’ 总被引:2,自引:0,他引:2
F. Dunemann D. Ulrich A. Boudichevskaia C. Grafe W. E. Weber 《Molecular breeding : new strategies in plant improvement》2009,23(3):501-521
Improving fruit quality of apple varieties is an important but complex breeding goal. Flavour is among the key factors of
apple fruit quality but in spite of the analytical and biochemical knowledge about volatiles little is known about the genetic
and molecular bases of apple aroma. The aim of this study was to use a saturated molecular linkage map of apple to identify
QTLs for aroma compounds such as alcohols, esters and terpenes, but also for a number of unidentified volatile compounds (non-targeted
analysis approach). Two parental genetic maps were constructed for the apple cultivars ‘Discovery’ and ‘Prima’ by using mainly
AFLP and SSR markers. ‘Discovery’ and ‘Prima’ showed very different volatile patterns, and ‘Discovery’ mostly had the higher
volatile concentrations in comparison with the Vf-scab resistant ‘Prima’ which has its origin in the small-fruited apple species Malus floribunda. About 50 putative QTLs for a total of 27 different apple fruit volatiles were detected through interval mapping by using
genotypic data of 150 F1 individuals of the mapping population ‘C3’ together with phenotypic data obtained by head-space solid phase microextraction
gas chromatography. QTLs for volatile compounds putatively involved in apple aroma were found on 12 out of the 17 apple chromosomes,
but they were not evenly dispersed. QTLs were mainly clustered on linkage groups LG 2, 3 and 9. In a first attempt, a LOX
(lipoxygenase) candidate gene, putatively involved in volatile metabolism, was mapped on LG 9, genetically associated with
a cluster of QTLs for ester-type volatiles. Implications for aroma breeding in apple are discussed. 相似文献