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991.
Solomon Benor Frank R. Blattner Sebsebe Demissew Karl Hammer 《Genetic Resources and Crop Evolution》2010,57(2):293-306
Little information is available regarding the biodiversity and potential use of jute (Corchorus species) in Ethiopian agriculture. The present study summarizes species’ occurrence, use, geographical distribution, ecology,
and ethnobotany of Corchorus species in Ethiopia. An ecogeographical study, conducted in the Amhara, Oromia and Gambella Regional States in 2005 and 2008
resulted in the collection of seven different species with more than 100 accessions. The study revealed low similarity in
species composition between the Regional States, indicating that each region has its own unique set of species. Species numbers
are higher in the north-eastern and south-western than the central part of the country. C. aestuans L. and C. tridens L. are restricted to humid lowlands of south-western part of Ethiopia, growing at elevations up to 490 m, whereas, C. urticifolius Wight et Arn., C. trilocularis L. and C. schimperi Cufod. were collected only in the north-eastern part of the country with elevation ranges of 1,380–2,130 m. The only species
collected at a higher elevation (>2,100 m) was C. schimperi Cufod. Farmers’ perception, indigenous knowledge and folk taxonomy of jute species are better in Gambella than the other
studied regions. Although several Corchorus species are reported from Ethiopia, these species are neither cultivated nor popularly used as leafy vegetables. This is
mainly due to lack of awareness or knowledge about the species use, and abundant distribution of the species that allows gathering
of edible leaves with little expenditure of time, labour and other resources. Our results revealed that some species are threatened,
which necessitates highest priority for jute germplasm conservation in the country. In addition, creating public awareness
about the use of jute species as a cheap source of leafy vegetable will play an important role to diversify food sources,
reduce malnutrition, and contribute to household income generation of the farming community. 相似文献
992.
A collection of seeds from five Acacia species was made in Egypt in 1856. Since then, the seeds have been stored at room temperature in different Swedish museums.
Due to the extreme longevity within the seeds of Acacia and related species, germination tests were performed on the now 151-year old seed. Seeds of two of the five species tested
germinated. The first, Acacia farnesiana (L.) Willd., had two seeds germinate, and Acacia melanoxylon R. Br. ex Ait. f. had one seed germinate. In addition, DNA was extracted from the aged seed and DNA preservation was analyzed.
Four of the tested species displayed well preserved DNA, whereas DNA from Albizia lebbeck (L.) Benth. showed signs of degradation. The 151-year longevity of the Acacia seeds is among the longest of dry-stored seeds reported. Several independent studies now report on extreme survival capacity
for Acacia and related genera suggesting that these genera are suitable for studies on the characteristics of seeds with long storage
performance. The results also demonstrate that herbaria and seed collections stored in museums and institutional depositories
can be alternate sources of plants genetic material and should be given conservation attention. 相似文献
993.
The characterization of plant genetic resources is the first step towards improving their use. The Spanish Plant Genetic Resources
Centre, which belongs to the National Institute for Agricultural and Food Technology Research (CRF-INIA), conserves accessions
of wild underground vetches collected in Spain. In the present work, 26 underground vetch accessions were characterized in
terms of their seed storage proteins (separated by SDS-PAGE) as a means of assessing the genetic variation of these plants
and their agronomic value. Vicia sativa cv. Vereda was used as control. A total of 54 bands were detected, of which 49 were polymorphic. Fifty eight different electrophoretic
patterns were observed in total. Protein bands were scored in terms of their presence (1) or absence (0) for all the seeds
studied, and two matrices constructed, one with all the bands present in each accession, the other with the different patterns
for each accession. Dendrograms based on the Jaccard similarity index and the UPGMA clustering method were produced from these
matrices, and the degree of genetic variation between and within accessions was calculated. The groups obtained were compared
with the chromosome number for each accession. The results reflect the great diversity of underground vetch seed storage proteins.
The aerial and underground seeds of 16 accessions were then analysed separately. In some cases, the aerial and underground
flowers of the same plant produced different proteins. 相似文献
994.
Alex Beharav Roi Ben-David Ivana Doležalová Aleš Lebeda 《Genetic Resources and Crop Evolution》2010,57(5):679-686
The wild lettuce, Lactuca aculeata Boiss. et Ky., is closely related and fully interfertile with cultivated lettuce, Lactuca sativa L. Altogether, 155 accessions of this wild species, which is rare conserved within the world’s germplasm collections, were
collected from 12 localities throughout northeastern Israel. Ten of these localities represent different sites across the
Golan Heights, while two, high-density populations were suprisingly found at the Hula Plain (first report of this species
in this region). Lactuca aculeata was recorded at various elevations (222–968 m a.s.l.) and habitats. The taxonomic status of 30 L. aculeata accessions was morphologically validated during ex situ seed regeneration of 31 random accessions representing all 12 localities. Characterization of 12 traits showed that the Israeli
populations of L. aculeata do not exhibit broad morphological variability, but more great levels of variation were obtained for developmental traits.
Relatively little variability was observed in the morphology of cauline leaves or in the distribution of anthocyanin pigmentation
in bracteae. In two cases, L. aculeata plants lacked trichomes in the inflorescence, a typical feature in the majority of plants. These unique collections of wild
lettuce may carry novel sources of genetic variation for a wide range of traits and, thus, should be of interest for careful
evaluation and exploitation in lettuce breeding. 相似文献
995.
996.
L. Riahi N. Zoghlami K. El-Heit V. Laucou L. Le Cunff J. M. Boursiquot T. Lacombe A. Mliki A. Ghorbel P. This 《Genetic Resources and Crop Evolution》2010,57(2):255-272
Three gene pools representative of Vitis vinifera L. subsp. vinifera (=subsp. sativa Beger) growing in the Maghreb regions (North Africa) from Tunisia (44), Algeria (31) and Morocco (18) and 16 wild grape accessions
(Vitis vinifera L. subsp. sylvestris (Gmelin) Beger) from Tunisia were analysed for genetic diversity and differentiation at twenty nuclear microsatellites markers
distributed throughout the 19 grape chromosomes. 203 alleles with a mean number of 10.15 alleles per locus were observed in
a total of 109 accessions. Genetic diversities were high in all populations with values ranging from 0.6775 (Moroccan cultivars)
to 0.7254 (Tunisian cultivars). F
st pairwise values between cultivated grapevine populations were low but found to be significantly different from zero. High
F
st pairwise values were shown between wild and cultivated compartments. Two parent offspring relationships, two synonyms and
two clones of the same cultivar were detected. The rate of gene flow caused by vegetative dissemination of cultivated grapevine
plants was not sufficient to genetically homogenise the pools of cultivars grown in different regions. The Neighbour Joining
cluster analysis showed a clear separation according to geographical origins for the cultivated grapevines gene pools and
revealed a high dissimilarity between cultivated and wild grapevine. However, three cultivars (Plant d’Ouchtata 1, Plant de
Tabarka 3 and Plant d’Ouchtata 3) are very close to wild accessions and may result from a hybridisation between cultivated
and wild accessions. The high level of differentiation between cultivated and wild accessions indicates that the cultivated
accessions do not derive directly from local wild populations but could mostly correspond to imported materials introduced
from others regions during historical times or derived from crossing between them. 相似文献
997.
Ilknur Solmaz Nebahat Sari Yildiz Aka-Kacar N. Yesim Yalcin-Mendi 《Genetic Resources and Crop Evolution》2010,57(5):763-771
Genetic diversity of the Turkish watermelon genetic resources was evaluated using different Citrullus species, wild relatives, foreign landraces, open pollinated (OP) and commercial hybrid cultivars by RAPD markers. The germplasm
was consisted of 303 accessions collected from various geographical regions. Twenty-two of 35 RAPD primers generated a total
of 241 reproducible bands, 146 (60.6%) of which were polymorphic. Based on the RAPD data the genetic similarity coefficients
were calculated and the dendrogram was constructed using UPGMA (Unweighted pair-group method with arithmetic average). Cluster
analysis of the 303 accessions employing RAPD data resulted in a multi-branched dendrogram indicating that most of the Turkish
accessions belonging to var. lanatus of Citrullus lanatus (Thunb.) Matsum et Nakai were grouped together. Accessions of different Citrullus species and Praecitrullus fistulosus (Stocks) Pangalo formed distant clusters from C. lanatus var. lanatus. Among 303 accessions, a subset of 56 accessions was selected representing different groups and a second dendrogram was constructed.
The genetic similarity coefficients (GS) within the Turkish accessions were ranged from 0.76 to 1.00 with 0.94 average indicating
that they are closely related. Taken together, our results indicated that low genetic variability exist among the watermelon
genetic resources collected from Turkey contrary to their remarkable phenotypic diversity. 相似文献
998.
Crop wild relatives are invaluable sources of novel genes for crop improvement and adaptation to changing environments. We
assessed phylogenetic relationships among 29 Linum accessions representing 16 species, including cultivated flax and its progenitor pale flax, based on four non-coding regions
of chloroplast DNA sequences. We obtained a cpDNA network showing that these 16 Linum species are appropriately connected based on previously defined taxonomic sections; these connections reflect the same evolutionary
pathways as determined from earlier morphological and cytological data. These relationships also support an earlier hypothesis
that cultivated flax is probably descended from a single domestication of pale flax plants, apparently for oil usage. The
detailed species network not only is significant for understanding evolutionary relationships of Linum species, but also useful for classifying exotic gene pools of cultivated flax as a part of the ongoing exploration of new
genetic diversity for flax improvement. 相似文献
999.
D. Arias J. Peñaloza-Ramírez O. Dorado P. Cuevas-Reyes Esaú Leyva Ana Luisa Albarrán-Lara G. Rangel-Altamirano 《Genetic Resources and Crop Evolution》2010,57(8):1227-1238
Jacaratia mexicana A. DC. (Caricaceae) is a tropical tree distributed throughout Mexico and Mesoamerica. Some evidence in Mexico indicates the
presence of an incipient domestication process in this species. Phylogeographical analyses can potentially determine contemporary
patterns of gene flow, isolation between population lineages, as well as historical processes such as population bottlenecks
or expansions on their geographical areas. In this study we reconstruct the phylogeographical patterns in populations of J. mexicana A. DC., in order to find differences between genetic variation among wild and cultivated populations utilizing chloroplast
DNA and nuclear DNA sequences. We generate a Bayesian phylogenetic tree, to estimate the divergence time between clades using
calibrated mutation rates. We also infer the demographic history of these populations using neutrality tests among wild and
cultivated accessions. We identified higher levels of haplotype and nucleotide diversity for the cpDNA and ITS types in wild
populations than in domesticated populations. These results indicate a reduction of genetic diversity derived from human selection
on domestication traits. Neutrality test suggests population expansion detected by the significant negative values of Fu’s
Fs in the cultivated populations of this specie. These process results in an excess of rare polymorphism with the fixation
of certain advantageous mutation throughout time, this implication are in accordance with the role of the strong selection
in the fruit traits of J. mexicana. The dated phylogeny constructed with BEAST program indicated a dispersion pattern for the J. mexicana ancestors across the South Pacific and South Eastern populations during the late Pliocene. Posterior dispersion and divergence
in the clades from Central Mexico and North Pacific are in agreement with the episodes of mountain-building in different regions
of Mexico. 相似文献
1000.
Dong Yibo Pei Xinwu Yuan Qianhua Wu Hongjin Wang Xujing Jia Shirong Peng Yufa 《Genetic Resources and Crop Evolution》2010,57(6):915-926
In this study, ecological, morphological and genetic diversity in 11 surviving populations of Oryza rufipogon Griff. from Hainan Island, China were investigated. These data served to provide much needed data in support of conservation strategies. The results divided O. rufipogon into six ecotypes. The cluster analysis based on 19 morphological features showed clear differentiation among populations or within populations. The cluster analysis based on SSR also revealed similar results. The ecological, morphological and genetic diversity observed in O. rufipogon resulted in the following conservation recommendations: (1) the four currently protected O. rufipogon localities should be maintained, due to the different ecological communities represented at these sites; (2) some populations, such as HL (Hele county, Hainan Island), should be protected, but some populations, such as FC (Fucheng county, Hainan Island) and DL (Dalu county, Hainan Island), might not be protected. (3) An isolation zone should be established to avoid possible introgression between O. sativa L. and O. rufipogon; and human activities that impact O. rufipogon should be reduced or eliminated. 相似文献