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1.
Naja Steen Andersen Gert Poulsen Bente Anni Andersen Lars Pødenphant Kiær Tina D’Hertefeldt Mike J. Wilkinson Rikke Bagger Jørgensen 《Genetic Resources and Crop Evolution》2009,56(2):189-200
When planning optimal conservation strategies for wild and cultivated types of a plant species, a number of influencing biological
and environmental factors should be considered from the outset. In the present study Brassica rapa was used to illustrate this: to develop Scandinavian conservation strategies for wild and cultivated B. rapa, DNA-marker analysis was performed on 15 cultivated and 17 wild accessions of B. rapa plus 8 accessions of the cross compatible B. napus. The B. rapa cultivars were bred in Sweden and Finland in 1944–1997 and the wild B. rapa material was collected from Denmark, Sweden and United Kingdom. The B. napus accessions were bred within the last 20 years in the Scandinavian countries. Results were based on scoring of 131 polymorphic
ISSR markers in the total plant material. A Bayesian Markov chain Monte Carlo (MCMC) approach implemented in NewHybrids demonstrated
a clear distinction of B. rapa and B. napus individuals except for three individuals that seemed to be backcrosses. The backcrossed hybrids descended from two Swedish
populations, one wild and one escaped. The overall pattern of genetic variation and structure in B. rapa showed that cultivated and wild B. rapa accessions formed two almost separated clusters. Geographical origin and breeding history of cultivars were reflected in
these genetic relationships. In addition, wild populations from Denmark and Sweden seemed to be closely related, except for
a Swedish population, which seemingly was an escaped cultivar. The study point to that many processes, e.g. spontaneous introgression,
naturalisation, breeding and agricultural practise affected the genetic structure of wild and cultivated B. rapa populations. 相似文献
2.
Maria Soledad Ureta Miguel Cantamutto Alicia Carrera Carla Delucchi Monica Poverene 《Genetic Resources and Crop Evolution》2008,55(8):1267-1277
Two introduced wild species Helianthus annuus L. and H. petiolaris Nutt. have become widespread in central Argentina and overlap the sunflower crop region. Intermediate off-type plants between
the wild and cultivated species are often found, which is of concern because of the recent release of imidazolinone resistant
varieties and the likely use of genetically modified sunflower cultivars. The progeny of 33 off-type plants obtained from
14 representative sites of the diffusion area were studied to confirm hybrid origin. Germination, survival, morphological
traits and days to flowering confirmed hybridization between crop and both wild species, when compared to eight accessions
of typical wild plants. Some progenies were presumably crop–wild H. annuus hybrids, some originated from the cross of cultivated plants and H. petiolaris, and two were the advanced generation of a cultivated hybrid. Hence, morphological traits are a good clue for the identification
of spontaneous hybrid plants at field. The results indicate that crop–wild hybridization and introgression occur at various
places in central Argentina. This fact may represent a way to herbicide resistance escape and future transgene escape if GM
sunflower cultivars are released for commercial use. 相似文献
3.
4.
Species that belong to the genus Triticum L. and the genetically related Aegilops L. genus are important genetic and economic resources because they have an evolutionary relationship with the two main agricultural
crops T. aestivum (bread wheat) and T. durum (durum wheat). Therefore, it is important to understand the genetic relationships among the cultivated wheat species and
their wild relatives. The latter have a great role in the improvement of cultivated wheat. Molecular markers are the best
choice and most reliable means to study these relationships accurately. In this study, we compared the efficiency of the biochemical
methods A–PAGE and SDS–PAGE on seed storage proteins and the molecular methods RAPDs and ISSRs to explore the genetic relationships
among seven species of Triticum and 20 Aegilops species. Three phylogenetic trees obtained in this study were compared with available classifications and phylogenetic trees
constructed earlier for these species. It was noted that the tree based on ISSRs data was the most congruent with those classification
and trees. This may be attributed to the fact that ISSRs is more specific, and therefore more reliable. This study is the
first to study genetic relationships among all species studied here using biochemical and molecular techniques. 相似文献
5.
Ronaldo Carvalho Santos José Luiz Pires Ronan Xavier Correa 《Genetic Resources and Crop Evolution》2012,59(3):327-345
Morphological variability of four wild species, one semi-cultivated and one cultivated species of Theobroma L., indigenous to Brazil and introduced in the Bahian cocoa-growing region, was characterized based on 35 quantitative and
13 qualitative traits. T. cacao, which shows a great diversity of conserved germplasm and many published references for morphological characterization, besides
of being one of the most cultivated species in Theobroma, was used for comparison as reference species. Sample size was defined for each organ evaluated and individual data set related
to leaf, flower, fruit and seed analyzed by a multivariate approach. The studied species showed a large variation for all
morphological traits evaluated. T. grandiflorum (Willd. ex Spreng.) Schum. and T. bicolor Humb. et Bonpl. showed the highest means for quantitative variables but were very divergent from each other considering flower
and qualitative traits. These were the only species that presented similar number of seeds in comparison with T. cacao. A species with smaller means for most traits was T. obovatum Klotzsch ex Bernoulli. The four wild species show white seeds while T. cacao shows purple ones. Multivariate analysis of variance indicates significant differences between Theobroma species for individual or grouped morphological fruit traits. The results from a cluster analysis were, in a general way,
congruent with botanical classification. The statistical analysis performed here was useful to identify a great variability
among evaluated traits and to distinguish the most divergent variables from Theobroma species. This work provided an important contribution to morphological characterization of polymorphic traits from different
organs of Theobroma species, which can help breeders in the future on the direction of interspecific crosses attempts. 相似文献
6.
H. Sanou N. Picard P. N. Lovett M. Dembélé A. Korbo D. Diarisso J. -M. Bouvet 《Genetic Resources and Crop Evolution》2006,53(1):145-161
Forty-one shea tree populations were sampled, spanning the main climatic zones of Vitellaria paradoxa Gaertn. in Mali and 10–35 adult trees were chosen randomly in the agroforestry parklands of each area. A total of 12 morphological
traits, related to tree morphology, fruit size and leaf form were measured. The variance components showed that variation
among populations represented the smaller percentage of the total variation with most of the values varying between 15 and
30%. The repeatability coefficient was generally high for tree within populations with values ranging between 0.23 and 0.78.
Although genetic correlations cannot be accurately estimated, due to difficulties in separation from environmental effects,
the results indicate that there is a very low genetic relation between the three kinds of traits, i.e., between those related
to tree, those related to leaf and those related to fruit. Leaf and fruit size traits were positively and significantly correlated
with rainfall, although tree circumference was negatively correlated with rainfall and the significantly larger shea trees
were noted in the drier areas – an observation thought linked to human management of the parklands. Soil drainage and parkland
density, however, did not explain differences between populations for fruit traits. This study offers preliminary information
for the development of a breeding population for a shea tree improvement programme. The value of repeatability, the low correlation
between sets of traits and the distribution of variation, suggest that selection of many individual trees within a few populations,
would allow capture of large genetic gain especially for fruit traits. 相似文献
7.
Anjula Pandey E. Roshini Nayar Kamala Venkateswaran D. C. Bhandari 《Genetic Resources and Crop Evolution》2008,55(1):91-104
The genetic diversity in genus Prunus is mainly confined to temperate regions of Himalaya and to a lesser extent in the sub-montane and hilly regions of peninsular
India. The cultivated and wild species of Prunus have tremendous potential for improvement and utilization. This paper includes the genetic resources of cultivated and wild
useful species of Prunus in India with emphasis on their distribution, potential traits/ useful characteristics and utilization. The information on
potential genetic resources of Prunus would be helpful in collection, evaluation, conservation and utilization of species. 相似文献
8.
G. Ram M. K. Bhan Ashok Ahuja S. R. Meena M. K. Kaul K. K. Gupta R. L. Jolly R. K. Khajuria 《Genetic Resources and Crop Evolution》2007,54(3):649-654
Variability studies were carried out among different accessions of Argyrolobium roseum for 12 metric traits under natural and cultivated conditions. Almost all characters showed higher values in cultivated than
natural population. Leaf breadth recorded highest CV (30.59%). Highest percentage of vitexin and D-pinitol (0.208 and 0.773%
dwb) was observed in RAR-7 and RAR-6, respectively, under cultivated conditions. Phenotypic coefficient was higher than genotypic
coefficient of variation. The association analysis revealed that root yield had positive significant correlation with 100
seed weight (r=0.839) biomass yield (r=0.601), where biomass yield had a positive significant correlation with leaf length, single pod weight. High heritability
(97.4–99.8%) coupled with moderate genetic advance ranged between (49–67%) as a percent of mean was observed for leaf breadth,
pod length, total foliage biomass yield and total root yield/plant. This suggests that direct selection for these traits is
suitable for the improvement of this crop. 相似文献
9.
Patrizia Erre Innocenza Chessa Concepción Muñoz-Diez Angjelina Belaj Luis Rallo Isabel Trujillo 《Genetic Resources and Crop Evolution》2010,57(1):41-54
The genetic relationships within and between wild and cultivated olives were examined and clarified in an isolated and restricted
area, such as the Mediterranean island of Sardinia. Wild (21 individuals) and cultivated olive trees (22 local cultivars from
a germplasm collection and 35 ancient trees) were genotyped by means of 13 SSR loci. Five cases of synonymy were observed
and nine distinct genotypes were identified in the collection. Five novel genotypes were also detected among the ancient trees.
Differences on the allelic composition and heterozygosity levels were found between wild and cultivated trees. Model-based
clustering method classified the olive trees into two major gene pools: (a) wild genotypes and (b) local cultivars from the
collection and from heritage olives. Regarding the cultivated plant material, we observed that: (a) most of the Sardinian
cultivars shared the same allelic profiles with the ancient cultivated trees and (b) the majority of these cultivars and all
the novel genotypes were not related to any other cultivars included in this study. These findings as well as the detection
of unique alleles and a certain wild genetic background at some cultivars revealed by the Bayesian analysis may indicate their
autochthonous origin. The synonymy cases found between local cultivars and Italian mainland cultivars indicate interchange
of genetic material among these growing areas, suggesting thus a possible allochthonous origin. The information obtained can
assist in the management of an olive collection and sheds some light on the survival of true oleasters and the origin of Sardinian
cultivars. 相似文献
10.
Evaluation of perennial wild <Emphasis Type="Italic">Cicer</Emphasis> species for drought resistance
About 90% of chickpea (Cicer arietinum L.) in the world is grown under rainfed conditions where drought is one of the major constraints limiting its productivity.
Unlike the cultivated chickpea, wild Cicer species possesses sources of resistance to multiple stresses; we therefore evaluated perennial wild Cicer species for resistance to drought. C. anatolicum, C. microphyllum, C. montbretii, C. oxydon and C. songaricum were compared with special checks; C. echinospermum, C. pinnatifidum and C. reticulatum and five cultivated chickpeas. After the cultivated chickpeas were killed, accessions were evaluated using a 1–5 scale, where
1 = highly drought resistant (no visible drought effect and full recovery after three successive wiltings) and 5 = highly
drought susceptible (leaves and branches dried out, no recovery at all). All accessions of perennial wild Cicer species were significantly superior to those annual wild species and the cultivated chickpeas including the best drought
tolerant chickpea, ICC 4958 under drought conditions. Perennial wild Cicer species did not only recover after wilting and drying out above ground level, they also tolerated high temperatures up to
41.8°C. But, they do not cross with the cultivated chickpeas. C. anatolicum should be taken account in long term breeding programs because it has closer affinities to the first crossability group than
the others. 相似文献
11.
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
12.
The International Cocoa Genebank, Trinidad (ICG,T) contains about 2000 cacao (Theobroma cacao L.) accessions. The purpose of the collection is to provide a source of genes for the genetic improvement of cacao through
breeding. In fulfilling this objective, it is imperative that this collection be evaluated to identify major sources of genes
for the genetic improvement of important agronomic–economic traits. In this study, 816 cacao accessions were evaluated for
resistance to Phytophthora pod rot (black pod disease), which causes enormous loss of yield in cocoa production throughout the world.The study identifies
promising resistant genotypes that could be exploited in cacao breeding programmes. It further compares the levels of resistance
to Phytophthora pod rot among two cacao types (wild and cultivated types), three major groups (Forastero, Trinitario and Refractario) and
11 accession groups (B, AM, CL, ICS, IMC, JA, LP, MOQ, NA, PA and TRD) . The distribution of scores for the 816 accessions
showed skewness towards the susceptible end of the disease rating scale, indicating that a large proportion (68.9%) of the
sample was susceptible (disease rating 6–8) to Phytophthora pod rot. However, 12.9% of the sample population was found to be resistant (disease rating 1–3) and 18.2% moderately resistant
(disease rating 4–5). Significant differences were observed between the wild and cultivated accessions and among the Forastero,
Refractario and Trinitario groups. Marked differences were also observed among 11 accession groups, each of which was represented
by at least 20 genotypes. Higher proportions of resistant (17.7%) and moderately resistant (22.6%) genotypes were observed
in the wild accessions than in the cultivated varieties (9.4% resistant and 14.4% moderately resistant). The Forastero group,
consisting of many wild accessions, was found to contain more resistant (18.0%) and moderately resistant (23.1%) genotypes
than either the Trinitario (4.8% resistant and 13.6% moderately resistant) or Refractario (11.3% resistant and 15.4% moderately
resistant). Among 11 accession groups, the largest percentage of resistant (24.2%) and moderately resistant (28.8%) genotypes
were found in the PA (Forastero). Different accession groups had varying proportions of resistant and moderately resistant
genotypes. This is not unexpected in an out-breeding crop such as cacao with a high level of heterogeneity. This finding reinforces
the idea of a pre-breeding programme (germplasm enhancement) to accumulate resistance genes over several populations as a
strategy for improving the genetic base of resistance in national cacao breeding programmes. One hundred and five promising
resistant genotypes were identified among the 816 accessions evaluated. These accessions are potential sources of resistance
genes for the development of high-yielding resistant varieties in cacao. 相似文献
13.
We implemented a regression-based method between pairwise relatedness estimated from markers and phenotypic similarity to
estimate heritability of traits related to leaf size and morphology in a wild tree population (Vitellaria paradoxa C.F. Gaertn.: shea tree). We then compared the results with heritability estimated with a classical pedigree-based method.
We tested both approaches in an agroforestry population of this tree species, a very important one and abundant in the Sudano-Sahelian
zone of Africa. Twelve microsatellite loci were used to estimate pairwise relatedness after selection of estimator coefficients
based on Monte Carlo simulation. The regression-based method applied to 200 individuals did not display a significant trend
with physical distance between trees for relatedness as well as for actual variance of relatedness. In consequence, estimates
of narrow-sense heritability of traits related to leaf size were not significant. The pedigree-based method using a progeny
test with 39 families and 15 individuals per family from the same population showed high and significant estimates of narrow-sense
heritability for the same traits (h2 = 0.36–0.95), demonstrating a marked genetic variation within the population. This discrepancy between methods stresses the
poor performance of the molecular marker-based method. This can be explained by the absence of fine-scale structure within
the agroforestry population of shea trees, other parameters being consistent with recommended values. The regression-based
method does not seem well adapted to the agroforestry tree population. New experiments in tree populations and theoretical
approaches are needed to evaluate the real potential of the marker-based methods. 相似文献
14.
15.
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
16.
Plant breeders are interested in strawberry species as donors of volatile compounds in breeding programmes because of the
diversity and intensity of wild strawberry aroma. Therefore, the topic of this paper is the prospective analysis of four accessions
of four wild strawberry accessions in comparison to a standard cultivar of Fragaria × ananassa Duch. by using human sensory, gas chromatography mass spectrometry (GCMS) and gas chromatography–olfactometry (GCO). The
wild species have higher aroma intensities compared with the cultivated one. The flavour quality differs significantly. Semiquantitative
GC analysis revealed that F. × ananassa cv. ‘Elsanta’ has the lowest content of volatile compounds whereas Fragaria moschata L. ‘Cotta’ has the highest. The aroma impressions, measured by GCO, support the findings of GCMS analyses. The nasal impact
frequency (NIF)-profiles of the wild types are more manifold and of higher intensities than those of the cultivated F. × ananassa cv. ‘Elsanta’ which corresponds with the overall flavour impression when tasting the fresh fruits. 相似文献
17.
V. B. Sreekumar A. M. Binoy Sarah T. George 《Genetic Resources and Crop Evolution》2007,54(8):1659-1665
Artocarpus altilis (Park.) Fosberg is an important fruit vegetable tree grown in the homesteads of southern part of India. To provide reasoned
scientific management practices and conservation measures, the pattern of morphological and genetic variation were investigated
for six populations using Amplified Fragment Length Polymorphism (AFLP) markers and 15 morphological traits. The use of five
selective primer combinations on 60 samples resulted a total of 414 bands in which 85% were polymorphic. The values of Nei’s
genetic distance varied from 0.0044 (Palai–Palghat) to 0.3376 (Palghat–Mangalore). Analysis of molecular variance revealed
most of the variation within populations (57.45%) than (42.55%) among populations. The genetic variation by AFLP data is not
reflected in quantitative morphological variables. However, the genetic and geographical distances were positively correlated
which were further well supported by the PCO analysis and Dollo-parsimony tree, both show the tendency of the individuals
to group according to the geographical localities. 相似文献
18.
19.
Daria Ryabova 《Genetic Resources and Crop Evolution》2007,54(5):973-980
Many crop wild relatives are usually widely distributed species, and in this relation a question arises about selecting populations
of special importance for conservation. Using Rubus idaeus as an example, we propose a compound selection of wild populations for in situ conservation. Twelve raspberry populations
in the Leningrad region have been evaluated from the point of view of their significance for in situ conservation. To exclude the run-wild forms from the evaluation process, we tried to identify them applying a mathematical
model developed by statusmetry method. The constructed model is based on morphological features of leaves of primocanes and
helps to distinguish the wild forms from the cultivated and run-wild ones. The wild raspberry populations were screened for
plants with features useful for cultivated raspberry improvement such as waxy cover presence, yellow fruiting plants, spinelessness,
fruiting primocanes and others. The diversity of wild raspberry populations was assessed by variation of morphological features,
presence of botanical varieties and polymorphism of seed storage proteins. The results of viability status assessment for
the chosen populations reflect the perspectives of their development and permit to determine the strategy and measures for
optimal conservation. 相似文献
20.
Hédia Hannachi Hilary Sommerlatte Catherine Breton Monji Msallem Mohamed El Gazzah Salem Ben El Hadj André Bervillé 《Genetic Resources and Crop Evolution》2009,56(3):393-403
The olive belongs to Olea, a complex genus and to a species with six subspecies. Subsp. europaea includes both the cultivated olive and the oleaster, the wild ancestor of the olive. Little is known on the phenotype of
fruits from subsp. cuspidata. We aimed to compare europaea and cuspidata trees for oil content and composition and to verify whether natural hybrids may exist between the two subspecies. Specimens
were from Kenya and putative natural hybrids between cuspidata and europaea were from Stellenbosch (South Africa). Cultivar and oleaster trees were sampled in France (continental and Corsica), Italy
(Continental and Sardinia) and Tunisia. We have examined the fruit (drupe) structure between subsp. cuspidata and europaea and extracted oil from the pulp, seed and total drupe. Comparison for oil content was made between the cultivated olive and
the oleaster and some cuspidata trees from Kenya. A few of cuspidata individuals from Botanical gardens do not enable phenotyping for oil content and composition. Oil composition analyses were
performed for the main fatty acids to compare the three taxa. We used microsatellite markers at 11 loci to compute genetic
distances between cuspidata, oleaster and cultivar trees and to reveal eventual hybrids. The SSR polymorphisms were huge between the two subspecies and
they revealed that putative hybrids were true hybrids sampled around olive orchards. The whole comparison of oil content shows
that olive cultivars display higher oil content than the subsp. cuspidata and that the oleaster trees are intermediate, whereas for oil composition of the drupe, cuspidata from Kenya shows less oleic acid than europaea. However, the cuspidata trees show seed oil composition similarities with the other two taxa. The discussion deals with possible reasons to explain
the differences and of the possible uses of these taxa for breeding both the olive and brown olive.
H. Hannachi and H. Sommerlatte have equal contribution in the article. 相似文献