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Sergio Segura Geo Coppens d'Eeckenbrugge Adriana Bohorquez Patrick Ollitrault Joe Tohme 《Genetic Resources and Crop Evolution》2002,49(2):111-123
DNA variation was studied at the intra- andinterspecific levels within the genus Passiflora, with particular emphasis on the subgenusTacsonia and its relationship with the subgenusPassiflora. AFLP fingerprints were generated for35 accessions from 21 species, 14 of which belong to subgenusTacsonia, and four to subgenusPassiflora. The morphologically intermediateP. manicata (subgenusManicata) was also included, as wereP. trinervia (subgenusPsylanthus) and P.alnifolia (subgenus Decaloba). The two latter were used as outgroup species. Twoprimer combinations generated 34–80 scorable fragments pergenotype for a total of 260 fragments. Polymorphism analyses spannedthe levels from individual genotype to section. SubgenusTacsonia presented wide genetic variability atboth intra- and interspecific levels, particularly within wildspecies. The classification based on these markers generally agreeswell with current taxonomic definitions of common species, but lesswith definitions of sections. A geographical component was evident inthe intraspecific variation of P.mixta, P.tripartita var. mollissimaand P. tarminiana, withwider variation in Ecuador and Peru than in Colombia and Venezuela.These same three species, plus P.cumbalensis, formed adjacent clusters, showingcloser affinity with each other than with the other species ofsubgenus Tacsonia. As expected, P. manicata clustered at anintermediate position between subgenera Tacsoniaand Passiflora. 相似文献
253.
The demand for live bottlenose dolphins for commercial use is growing in Mexico, making the need for stock assessment and management ever more essential given their protected status. Tursiops truncatus is known to exhibit high levels of phenotypic polymorphisms. In the Gulf of California (GC), coastal and offshore ecotypes have been identified based on morphological, behavioral and ecological evidence, including different prey and habitat preferences. However, the extent to which this ecological and phenotypic variation is genetically correlated is unknown. Here we assess this correlation in GC bottlenose dolphins classified as coastal or offshore based on habitat, morphological and trophic evidence. Significant (p < 0.0001) haplotype heterogeneity (exact test) and genetic differentiation (FST = 0.069) were found in the mitochondrial control region, indicating some reproductive isolation between ecotypes. As elsewhere, coastal dolphins were less diverse than offshore. Phylogenetic analyses revealed paraphyletic coastal and offshore lineages and no evidence of lineage sorting, possibly due to recent isolation or gene flow. This is the first time that genetic, morphological and stable isotope evidence has been used to recognize ecotypes as different stocks for management purposes in bottlenose dolphins. Our results indicate that diversifying forces are shaping their phenotypic and genetic variation in the GC. Management and conservation efforts in this strategic region should aim to preserve these forces. 相似文献
254.
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
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256.
DH Hathaway PA Gilman JW Harvey F Hill RF Howard HP Jones JC Kasher JW Leibacher JA Pintar GW Simon 《Science (New York, N.Y.)》1996,272(5266):1306-1309
Doppler velocity observations obtained by the Global Oscillation Network Group (GONG) instruments directly measure the nearly steady flows in the solar photosphere. The sun's differential rotation is accurately determined from single observations. The rotation profile with respect to latitude agrees well with previous measures, but it also shows a slight north-south asymmetry. Rotation profiles averaged over 27-day rotations of the sun reveal the torsional oscillation signal-weak, jetlike features, with amplitudes of 5 meters per second, that are associated with the sunspot latitude activity belts. A meridional circulation with a poleward flow of about 20 meters per second is also evident. Several characteristics of the surface flows suggest the presence of large convection cells. 相似文献
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258.
Cabaleiro Cristina Pesqueira Ana M. Segura Antonio 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(3):733-747
European Journal of Plant Pathology - The mealybug Planococcus ficus is one of the main vectors of Grapevine leafroll associated virus-3 (GLRaV-3), which was commonly detected in cv... 相似文献
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260.
A 13-year-old Morgan gelding was examined for right forelimb lameness and tenosynovitis of the right common carpal sheath of the digital flexor tendons. The horse had moderate right forelimb lameness at the trot and marked effusion of the right common carpal sheath of the digital flexor tendons. Ultrasonographic examination revealed a soft tissue mass within the proximal pouch of the affected tendon sheath, located adjacent to the distal physis of the radius. Cytology and culture of the fluid revealed a sterile, eosinophilic tenosynovitis. Tenoscopic exploration confirmed the presence of a capsulated soft tissue mass. Thecotomy was required to fully debride the mass, which histology revealed to be a mast cell tumour. At 22 months postoperatively, the horse developed mild right forelimb lameness and eosinophilic tenosynovitis because of recurrence of the mastocytoma. Mastocytosis is a possible differential diagnosis in any horse exhibiting lameness associated with tenosynovitis. Surgical excision combined with rest and postoperative intrasynovial and systemic corticosteroids may be palliative. 相似文献