共查询到20条相似文献,搜索用时 15 毫秒
1.
Endashaw Bekele Mulatu Geleta Kifle Dagne Abigail L. Jones Ian Barnes Neil Bradman Mark G. Thomas 《Genetic Resources and Crop Evolution》2007,54(7):1419-1427
Complete sequences for the internal transcribed spacers of the 18s–26s nuclear ribosomal DNA were generated to establish phylogenetic
relationships among five species of the genus Guizotia. Parsimony analysis and pairwise distance data produced a single tree with four clearly distinguished clades that accord
with previously reported chromosomal data. The clades produced here have been discussed with reference to existing taxonomic
treatments. It appears that Guizotia scabra ssp. scabra, G. scabra ssp. schimperi and Guizotia villosa have contributed to the origin of Guizotia abyssinica, the cultivated species of the genus. The present composition of the species of genus Guizotia and the subtribe the genus presently placed in are suggested to be redefined. 相似文献
2.
Amplified fragment length polymorphism (AFLP) analysis was used to evaluate the genetic relationships and diversities of Chinese
vegetable mustards. Fourteen pairs of primers generated a total of 366 scorable fragments among 16 accessions of Brassica juncea studied, of which 296 bands were polymorphic with an average of 21.1% polymorphic bands per primer combination. Genetic similarities
were obtained using Nei and Li similarity coefficients, and a dendrogram of the 16 accessions was made by UPGMA clustering
method. The Nei and Li Similarity coefficient value ranged from 0.63 to 0.88. This result indicated that the 16 accessions
of B. juncea possessed high level genetic variations. The cluster analysis showed that the vegetable mustards could be grouped into two
main groups and some minor rami, which was partially in accordance with the traditional classification that based on different
edible organs of vegetable mustards. The incongruity between morphological and molecular classification might be attributed
to the high selection pressure during domestication of Chinese vegetable mustards, producing some accessions with similar
genetic backgrounds evolving into abundant morphological variations. The great diversification among Chinese vegetable mustards
not only provides an excellent object for molecular evolution research of B. juncea but also is of great value for widening the genetic basis of breeding programs and breeding materials selection. Besides,
our study also indicates that AFLP are informative and can provide significant insights for genetic diversity research in
B. juncea. 相似文献
3.
Reciprocal crosses were made between Brassica carinata and its related species Sinapis alba. Pollen germination studies indicated the presence post-fertilization barriers in both ways. Sequential ovary–ovule culture
helped to realize the intergeneric hybrids from the cross S. alba × B. carinata. The F1 obtained was confirmed as a hybrid based on morphology, cytology and isozyme studies. The hybrid was backcrossed to its male
parent and obtained BC1 seeds, which were used to raise BC1 generation. The BC1 generation plants were further backcrossed to B. carinata in order to develop alloplasmic lines. 相似文献
4.
H. Chennaoui S. Marghali M. Marrakchi N. Trifi-Farah 《Genetic Resources and Crop Evolution》2007,54(2):389-397
Sequences of the internal transcribed spacers (ITS) of nuclear ribosomal DNA were analysed to precise their length (637–643
bp) and resolve phylogenetic relationships among eight Mediterranean species of the genus Hedysarum (Fabaceae). The infra-specific variability levels of the ITS sequences of spontaneous population of H. coronarium proved a lack of polymorphism both in the length and in the sequences examined in this species. Hence, a consensus ITS sequence
characterising each Hedysarum species has been investigated for analysis of inter-specific polymorphisms. The level of variation of ITS sequence was high
enough to make the ITS1 and ITS2 a useful tool for phylogenetic reconstruction. However, ITS2 seems to be relatively more
polymorphic and more informative than ITS1 regarding length or GC percent. The phylogenic relationships in the genus Hedysarum based on ITS1 and ITS2 sequences taken independently or together, are discussed in the context of current work in molecular
biosystematics. Results exhibited the distinctiveness of the two H. spinosissimum subspecies (i.e. H. spinosissimum ssp. capitatum and H. spinosissimum ssp. spinosissimum). In addition, the great similarity of the ITS sequences between H. coronarium (the only cultivated species of the genus) and H. carnosum suggests the usefulness of the latter in selection programmes to improve pastoral production in semi-arid areas. 相似文献
5.
S. Louarn A. M. Torp I. B. Holme S. B. Andersen B. D. Jensen 《Genetic Resources and Crop Evolution》2007,54(8):1717-1725
Fifty-nine Brassica oleracea cultivars, belonging to five botanical varieties, were evaluated for microsatellite (SSR) polymorphisms using 11 database
sequence derived primer pairs. The cultivars represented 12 broccoli (Brassica oleracea var. italica), ten Brussels sprouts (B. o. var. gemmifera), 21 cabbage (B. o. var. capitata, including the groups white and red cabbage), six savoy cabbage (B. o. var. sabauda), and ten cauliflower (B. o. var. botrytis) cultivars from 13 seed suppliers. The 11 primer pairs amplified in total 47 fragments, and differentiated 51 of the cultivars,
whereas the remaining eight cultivars were differentiated from the rest in four inseparable pairs. All SSR markers, except
one, produced a polymorphic information content (PIC value) of 0.5 or above. The average diversity for all markers within
the tested material was 0.64. There was no major difference in the diversity within botanical varieties and groups. The cluster
analysis and the resulting dendrogram showed that the cultivars tended to group within these taxonomic units. The present
study substantiates the use of microsatellite markers as a powerful tool for cultivar differentiation and identification in
vegetable brassicas. 相似文献
6.
K. Aitken J. Li L. Wang C. Qing Y. H. Fan P. Jackson 《Genetic Resources and Crop Evolution》2007,54(7):1395-1405
Erianthus rockii, a wild relative of sugarcane, is drought and cold tolerant, and both are potentially important agronomic traits to the sugarcane
industry worldwide. As such it is of interest as a source of parental germplasm to sugarcane breeders and is currently being
used in sugarcane introgression programs in both China and Australia. To date morphological characters have been used to verify
the putative hybrids produced. Two crosses were generated between two different Saccharum species and two E. rockii accessions. Over 400 AFLP markers were used to identify the intergeneric hybrid progeny as well as determine hybrid diversity.
Both crosses generated hybrids but efficiency levels were very different and are probably related to the different Saccharum parent used in each cross. Cross 1 was between a Saccharum officinarum and E. rockii and generated 100% hybrid progeny. Cross 2, however, was between a sugarcane hybrid (S. officinarum × Saccharum spontaneum) and E. rockii and only 10% of the progeny were intergeneric hybrids. Inheritance of markers in the progeny was analysed and for both crosses
there were equal numbers of markers from both parents indicating n + n transmission of chromosomes. This is the first verification of E. rockii hybrids with molecular markers. It may now be possible to exploit genes of value from E. rockii in sugarcane breeding programs. 相似文献
7.
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
8.
Jorge Cunha Margarida Baleiras-Couto José P. Cunha Jorgete Banza Adelaide Soveral Luís C. Carneiro José E. Eiras-Dias 《Genetic Resources and Crop Evolution》2007,54(5):981-988
Wild populations of Vitis vinifera L.␣have been located in Portugal. Morphological characterization was carried out in three populations located in Alcácer
do Sal, Castelo Branco, and Montemor-o-Novo, and then compared using multivariate discriminant analysis. These populations
were from three different hydrological basins, therefore cross-pollination was not possible. It was verified that in each
population all plants were different. The data suggest that the frequency of female and male plants is rather variable in
wild populations. The morphology of the adult leaf, from the Alcácer do Sal population, had particular features when compared
with Castelo Branco and Montemor-o-Novo populations, which were more homogeneous. The length of teeth compared with width
at the end of the base, and the density of prostrate hairs between and on main veins (lower side) were the variables which
allowed the best discrimination among populations. 相似文献
9.
Bettina Heider Elke Fischer Tanja Berndl Rainer Schultze-Kraft 《Genetic Resources and Crop Evolution》2007,54(3):529-542
Pueraria montana var. lobata and P. phaseoloides originating from tropical Asia and parts of Oceania are ecologically and economically important legumes that are used as
green manure, cover crop or forage plants. Conservation and use of plant genetic resources require an understanding of the
extent and distribution of genetic diversity in any given region. In this study, genetic variation of five P. montana var. lobata and 16 P. phaseoloides accessions was analysed developing a random amplified polymorphic DNA (RAPD) marker methodology for Pueraria species and thereby creating basic data for follow-up research and the development of conservation strategies. Seeds were
collected from native populations in Bac Kan Province, a mountainous region in Northeast Vietnam. P. montana var. lobata presented a high level of variation with 54.3% of the detected markers being polymorphic, whereas P. phaseoloides exhibited an intermediate to high level of variation (45.5%). The P. montana var. lobata accessions clustered in congruence with their eco-geographical origin. For P. phaseoloides no correspondence between sampling sites and genetic differentiation was found. Inter-population differentiation was measured
as Jaccard's similarity coefficient (JSC). Mean JSC amounted to 0.35 in P. montana var. lobata and 0.52 in P. phaseoloides. Results are compared to other genetic studies of herbaceous legumes and conservation strategies are suggested. 相似文献
10.
N’Diaye Amidou Noirot Michel Hamon Serge Poncet Valérie 《Genetic Resources and Crop Evolution》2007,54(5):1011-1021
The phenotypic and genetic differentiation between the two related Coffea species (C. liberica Hiern and C. canephora Pierre) was examined. These species differed markedly in terms of leaf, inflorescence, fruit and seed characters. A genetic
map of the interspecific cross Coffea liberica × C. canephora was constructed on the basis of 72 BC1 hybrids. Eighty-three AFLP markers, four inter simple sequence repeats (ISSR) and
five microsatellites corresponding to Coffea liberica species-specific markers were mapped into 16 linkage groups. The total length of the map was 1502.5 cM, with an average of
16.3 cM between markers and an estimated genome coverage of 81%. The two species were evaluated relative to 16 quantitative
traits and found to be significantly different for 15 of them. Eight QTLs were detected, associated with variations in petiole
length, leaf area, number of flowers per inflorescence, fruit shape, fruit disc diameter, seed shape and seed length. Results
on segregation distortion and the under-representation of particular markers were interpreted in terms of genome differentiation.
The implications for the introgression of QTLs involved in advantageous morphological traits (number of flowers per inflorescence,
fruit and seed shape) are discussed. 相似文献
11.
12.
S. D. Segura G. Coppens d’Eeckenbrugge C. H. Ocampo P. Ollitrault 《Genetic Resources and Crop Evolution》2005,52(4):455-463
In a general study of banana passion fruit genetic resources, diversity was analyzed in the two main cultigens, P. tripartita
var. mollissima and P. tarminiana, and their closest wild relative, P. mixta, scoring isozyme bands (IDH,PGM,ACP,PGD,DIA,andPRX)
on288 plants from 31 accessions. Polymorphismandallelic richness, Nei diversity indices, and neighbor joining clustering showed
that variation was poor in the cultigens in northern and central Colombia, while P. mixta appeared much more polymorphic.
The populations of P. tripartita var. mollissima and P. mixta from southern Colombia and Ecuador show higher diversity values
and are clearly differentiated from those of central and northern Colombia. This geographic component of variation is even
stronger than the interspecific one, which suggests a close relation and a regular gene flow between these two species. In
contrast, all the accessions of P. tarminiana constitute a clearly differentiated group, even if some introgression with P.
tripartita var. mollissima is also suspected. The high variation observed in the southern region indicates the proximity of
a center of diversity for banana passion fruit and collecting in Ecuador, Peru and Bolivia is recommended. The high diversity
of P. mixta and the evidence of gene flow with P. tripartita var. mollissima constitute a favorable context for the implementation
of in situ conservation strategies. 相似文献
13.
M. C. Vaz Patto M. Fernández-Aparicio A. Moral D. Rubiales 《Genetic Resources and Crop Evolution》2007,54(7):1517-1521
Several Lathyrus species have a considerable potential as alternative pulses in sustainable dryland farming systems mainly due to their high
tolerance to drought and disease resistance. Powdery mildew is a serious disease affecting several Lathyrus species. Little is known on the availability of resistance and the underlying resistance mechanisms against powdery mildew
in the Lathyrus genus. The present study assessed and characterized the resistance reaction to powdery mildew, Erysiphe pisi, in a collection of Iberian Lathyrus cicera accessions. In general, a compatible reaction with no macroscopically visible necrosis was observed but accessions with reduced
disease severity despite of a high infection type have also been identified. This Partial Resistance was in some accessions
only expressed in the adult plant stage. The controlling genes of the Lathyrus resistance mechanisms can be of great interest not only for the Lathyrus improvement per se but also for related legume species, like field pea. 相似文献
14.
Naod Beteselassie Chemeda Fininsa Ayele Badebo 《Genetic Resources and Crop Evolution》2007,54(2):337-343
Seedlings of 41 emmer (Triticum dicoccon Schrank) and 56 durum (T. durum Desf.) wheat accessions were evaluated for their response to stem rust (Puccinia graminis f. sp. tritici) infection under greenhouse condition at Kulumsa Agricultural Research Center, Ethiopia. The objectives were to identify
tetraploid wheat accessions that could serve as sources of resistance to stem rust, and postulate the stem rust (Sr) resistance genes through multipatotype testing. The test included screening of accessions for stem rust resistance and multipatotype
testing. To ensure vigorous screening, a mixture of six isolates (Si-1a, Am-2, Ku-3, Dz-4a, Ro-4 and Na-22) that were collected
from severely infected emmer, durum, and bread wheat (Triticum aestivum L.) varieties of major wheat growing areas of Ethiopia was used as inocula. Out of the tested accessions, 18 emmer and 6
durum accessions exhibited low infection types (0–2) response and hence selected as a source of resistance to stem rust infection.
Multipatotype testing was done to postulate Sr genes in the selected accessions. In the test, 10 different stem rust races (A2, A9, A11, A14, A16, A17, B3, B7, B15, and
B21), 33 stem rust differential lines, and a universal susceptible check variety, Morocco were used, The high (3–4) and low infection type reaction patterns of the tested accessions and differential lines were used
to postulate the genes that exhibit gene-for-gene relationship. The presence of Sr 7b, 8b, 9a, 9b, 10, 14, 24, 27, 28, 29, 30, 31, 32 and Tt-3+10 genes were postulated in 16 selected emmer and 5 durum wheat accessions. Efforts to transfer these valuable Sr genes from cultivated tetraploid wheats could be rewarding to get stem rust resistant varieties and boost wheat production. 相似文献
15.
S. Desai Ch. Narayanaiah Ch. Kranti Kumari M. S. Reddy S. S. Gnanamanickam G. Rajeswara Rao B. Venkateswarlu 《Biology and Fertility of Soils》2007,44(1):229-234
Jatropha (Jatropha curcas L.) is a non-edible oil-seed plant with adaptability to marginal semi-arid lands and wastelands. The Indian Government is
promoting jatropha to reduce dependence on the crude oil and to achieve energy independence by the year 2012, under the National
Biodiesel Mission. Selected strains of Bacillus spp., either supplemented with or without chitin, were tested for their ability to promote growth of jatropha seedlings in
pot culture studies. The strains supported growth of jatropha seedlings up to 42 days after sowing. Among all strains, Bacillus pumilus (IM-3) supplemented with chitin showed over all plant growth promotion effect resulting in enhanced shoot length (113%),
dry shoot mass (360%), dry root mass (467%), dry total plant mass (346%), leaf area (256%), and chlorophyll content (74%)
over control. Treating seeds with strain IM-3 without chitin resulted in enhanced dry shoot mass (473%), dry total plant mass
(407%), and chlorophyll content (82%). However, Bacillus polymyxa (KRU-22) with chitin supported maximum root length (143%). Either strain IM-3 alone or in combination with other promising
strains could be promoted further for enhanced initial seedling growth of jatropha. 相似文献
16.
Marc Moragues Marian Moralejo Mark E. Sorrells Conxita Royo 《Genetic Resources and Crop Evolution》2007,54(5):1133-1144
A comprehensive characterization of crop germplasm is critical to the optimal improvement of the quality and productivity
of crops. Genetic relationships and variability were evaluated among 63 durum wheat landraces from the Mediterranean basin
using amplified fragment length polymorphisms (AFLPs) and microsatellites markers. The genetic diversity indices found were
comparable to those of other crop species, with average polymorphism information content (PIC) values of 0.24 and 0.70 for
AFLP and microsatellites, respectively. The mean number of alleles observed for the microsatellites loci was 9.15. Non-metric
multi-dimensional scaling clustered the accessions according to their geographical origin with the landraces from the South
shore of the Mediterranean Sea closely related. The results support two dispersal patterns of durum wheat in the Mediterranean
basin, one through its north side and a second one through its south side. 相似文献
17.
M. C. Vaz Patto P. M. Moreira V. Carvalho S. Pego 《Genetic Resources and Crop Evolution》2007,54(7):1555-1563
The Portuguese maize bread (“broa”) manufactured from traditional maize landraces still plays an important economic and social
role on Central and Northern rural communities of the country. However the traditional maize landraces agricultural systems
are changing. Local maize landraces are in risk of disappearing because of the progressive adoption of hybrid varieties not
suitable for bread production. These changes are contributing to a major loss of genetic diversity. An expedition took place
in the Central region of Portugal (Beira Interior and Beira Litoral) with the purpose of collecting enduring maize landraces
with technological ability for bread production and to access the possibility of establishing a participatory plant breeding
and conservation program. A total of 51 different maize landraces and 175 other varieties of associated crops were collected.
Maize landraces showed to maintain high diversity and potential for improvement. The production relayed on small farms with
polycrop, quality oriented, sustainable systems. A participatory plant breeding and conservation program would be possible
on this region with the proviso that local authorities would be involved. This program would allow a higher valuation of these
maize populations, contributing to halt the current loss of these unique Portuguese maize landraces. 相似文献
18.
Gert Poulsen Claus Holten Roland von Bothmer 《Genetic Resources and Crop Evolution》2007,54(5):1105-1115
Dead seeds of a fodder beet cultivar ‘Elvetham’ stored under ambient conditions since 1880 were compared to a homonymous sample
preserved in an on-farm situation in Denmark. DNA was isolated from single seeds and successfully applied to Amplified Fragment
Length Polymorphism (AFLP) analysis of the accessions. Six primer pairs were used to determine the similarity between the
two accessions based on 112 polymorphic bands. Furthermore, similarity among seven cultivars of fodder beets representing
the main types used in Scandinavia at the end of the 19th century was determined. This analysis was based on 152 polymorphic
bands. Differentiation among the seven cultivars was determined to a mean G
ST value of 0.438, while G
ST between the two ‘Elvetham’ accessions was 0.266. A principal coordinate analysis based on jaccards similarity index illustrates
that the two ‘Elvetham’ accessions are different from each other. The differentiation is higher than the value found between
two separate ‘Eckerndorfer’ accessions. The results indicate that the cultivated accession has changed. Additionally, the
value of applying old dead seed material for documentation in gene banks is demonstrated.
During the analysis it was found that DNA isolated from seeds and leaves behaved differently in the AFLP process, however,
the two fractions assigned to their common accession. 相似文献
19.
Genlou Sun 《Genetic Resources and Crop Evolution》2007,54(8):1737-1746
Elymus trachycaulus complex species are known for their morphological variability, but little is known about their genetic basis. The phylogenetic
relationships among the E. trachycaulus complex, and their systematic relation to other species in Triticeae remain unknown. Nucleotide diversity of ribulose-1,5
bisphosphate-carboxylase (rbcL) gene in E. trachycaulus complex species and several other Triticeae was first characterized and compared. A primary conclusion of the present study
is that nucleotide diversity for rbcL gene in E. trachycaulus species was detected with the estimates of nucleotide diversity θ = 0.00039 and π = 0.00043. The estimate of nucleotide diversity
in rbcL gene for species with different genome constitution here ranged from 0.00099 (π) and 0.00099 (θ) for the species with Ns
genome to 0.00226 (π) and 0.00291 (θ) for the species with St genome. The phylogenetic relationships of these species were
assessed using these rbcL sequences. A total of 47 variable positions including 19 parsimony-informative sites were detected among 24 accessions of
18 species/subspecies. The species with St, H/I and Ns genomes well separated from each other, and formed a three distinct
clades with higher bootstrap values support for both Parsimony and NJ analyses. The St genome containing species is sister
group of H/I genome containing species. Our result confirms that Pseudoroegneria is the maternal genome donor to these Elymus species studied here, regardless of their distribution. Elymus trachycaulus complex are more related to each other than to E. glaucescens, E. patagonicus, and E. solandri. This study suggested that Elymus species with StH genomes may form from multiple closely related sets of donors. 相似文献
20.
Marie Malice Nicolas Martin Audrey Pissard Jorge A. Rojas-Beltran Antionio Gandarillas Pierre Bertin Jean-Pierre Baudoin 《Genetic Resources and Crop Evolution》2007,54(4):685-690
ISSR molecular markers have been used to investigate genetic diversity of oca (Oxalis tuberosa Mol.), an Andean neglected tuber crop species. Sampling procedure allowed a preliminary study of the genetic diversity at
the intra- and intervarietal levels. Twenty tuber lots conserved in situ in the microcentre of Candelaria and ex situ in the Toralapa Centre (Bolivia) were identified. Four ISSR primers amplified a total of 25 fragments of which 17 (68%) were
polymorphic. These experiments show that the structure of oca varieties is mainly based upon vernacular names with a greater
differentiation among tuber lots than within them, supporting agromorphological data. ISSR technique enlightened the existence
of heterogeneous varieties in oca and divergence between in situ and ex situ conservation strategies. These observations are potentially linked to the different ways of management of tubers in these
two conservation systems. 相似文献