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1.
Felício LP Silva EM Ribeiro V Miranda CT Vieira IL Passos DC Ferreira AK Vale CR Lima DC Carvalho S Nunes WB 《Genetics and molecular research : GMR》2011,10(1):16-24
Luehea divaricata is a native plant of the Brazilian Cerrado, known as "a?oita-cavalo". It is used as a popular herbal medicine in the treatment of dysentery, bleeding, arthritis, tumors, ulcers, and gangrenous wounds. Considering that herbal medicines sometimes provoke tumors and/or may prevent mutational events, it is important to study the action of these natural drugs on DNA. Aqueous extract of the bark of L. divaricata was evaluated at three different concentrations (0.10, 0.30, 0.50 mg/mL), individually and in combination with the neoplastic drug doxorubicin (DXR), by the somatic mutation and recombination test (SMART/wing) in Drosophila melanogaster. Distilled water was included as a negative control. The mutation frequency in the treatments with L. divaricata extract alone was not significantly higher than in the negative control for standard (ST) and high bioactivation (HB) crosses. When L. divaricata extract was combined with DXR, there was a significant reduction in the frequency of spots when compared to DXR alone, in both crosses. Further studies with other experimental models would be useful to confirm that L. divaricata extract is not harmful and that it could be used in the prevention of cancer. 相似文献
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We isolated eight polymorphic microsatellites from the neotropical tree Luehea seemannii for gene flow and genetic structure studies. We used a streptavidin subtractive enrichment technique to develop a library of CA/GT repeats. Eight loci were screened for diversity from 96 individuals from Barro Colorado Island (BCI) and neighbouring Gigante peninsula in Panama. Luehea seemannii shows moderate levels of genetic diversity within these two populations. Allelic richness ranged from four to nine alleles and averaged 6.44 alleles per locus. Average expected heterozygosity was 0.65 on BCI and 0.60 on Gigante. Results are compared to microsatellite data from another wind‐dispersed gap colonizing species common in Panama. 相似文献
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Endophyte microorganisms are organisms that live inside plants without causing any apparent damage to their hosts. Since all plants exhibit endophyte microorganisms, it is believed that mutual association is of great importance in nature. Luehea divaricata (Martius & Zuccarini), known popularly in Brazil as agoita-cavalo, is a big-sized tree with a wide distribution in the country that possesses medicinal qualities for: dysentery, leucorrhea, rheumatism, blennorrhoea, tumors, bronchitis, and depuration. This research aims at isolating and molecularly characterizing fungi isolates from L. divaricata by sequence analysis of ITS1-5.8S-ITS2 rDNA. Further, the colonization of endophyte in the host plant by Light and Scanning Electron Microscopy will also be investigated. Whereas, genera Alternaria, Cochliobolus, Diaporthe, Epicoccum, Guignardia, Phoma, and Phomopsis, were identified; rDNA sequence analysis revealed intra-species variability among endophyte isolates of the genus Phomopsis sp. Light and Scanning Electron Microscopy techniques showed the presence of endophyte fungi inside L. divaricata leaves, inhabiting inter- and intra-cellular spaces. These types of extensive colonization and dissemination were reported throughout all the leaf parts in palisade parenchyma, esclerenchyma, spongy parenchyma, adaxial epidermis, and vascular bundle indicating colonization of endophytes in múltiple structural sub-niches in the host plant. 相似文献
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Fábio de Almeida Vieira Cristiane Gouvêa Fajardo Anderson Marcos de Souza Cristiane Aparecida Fioravante Reis Dulcinéia de Carvalho 《Tree Genetics & Genomes》2012,8(6):1191-1201
We present a case study of the relationship between spatial genetic structure (SGS) and age structure in Protium spruceanum (Burseraceae), an insect-pollinated, mass-fruiting, and secondary bird-dispersed tree, as determined through variation in allozyme loci. Using ten polymorphic loci, we investigated spatial and temporal patterns of a genetic structure within a 40?m?×?60?m plot in a small (1.0?ha) fragment of Atlantic Rainforest to investigate the processes shaping the distribution of genetic diversity. Individuals (n?=?345) from seedlings to adults were grouped and analyzed in four diameter classes. The results showed a high average level of genetic diversity (H e?=?0.438), but genetic diversity parameters did not vary significantly among cohorts. The spatial distribution pattern analysis of individuals showed significant levels of aggregation among small- and medium-diameter classes and random distribution among the highest diameter class, likely due to processes of competitive thinning. There was an association between demographic and SGS at short distances (less than 10?m) which is likely the consequence of restricted seed dispersal. The degree of SGS decreased across small- to large-diameter classes. We inferred that limited seed dispersal and subsequent density-dependent mortality from the family clusters are responsible for the observed changes in fine-scale SGS across different demographic classes. 相似文献
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It is controversial the role played by Meliponina bees in the pollination of mass flowering trees with small generalized flowers (FMPG), very common group of trees in the tropical forest canopy. The species richness and relative abundance of flower visiting insects of the mass flowering tree Stryphnodendron pulcherrimum were measured to test the hypothesis of tight ecological association between these generalist bees and FMPG and to evaluate the effect of this relationship upon the reproductive success variation among tree crowns. The flower visiting insects were sampled on 10 flowering tree crowns at the Atlantic Rainforest in southern Bahia. Altogether, 553 visiting insects were collected during the flowering period of S. pulcherrimum: 293 (52%) Meliponina bees out of 438 bees (79.4%). All tree crowns were visited by Meliponina, with the proportion of these bees ranging from 27% to 87%. The tight ecological association between FMPG trees and Meliponina bees is supported by the observed pattern of spatial relationship. Both the relationship between variation of fruit set among tree crowns and species richness (r = 0.3579; P = 0.3098) or relative abundance (r = 0.3070; P = 0.3881) of Meliponina were not statistically significant. Likely a threshold of minimum relative abundance combined with the absolute abundance of these bees explain the fruit set variation among tree crowns of S. pulcherrimum, even by self-pollination. We tested this assumption with a preliminary analysis of Melipona bee genera distribution among the tree crowns. 相似文献
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Mats Thulin 《Nordic Journal of Botany》1999,19(3):337-339
Hibiscus ceratophorus , sp. nov. in H . sect. Furcaria , from coastal and subcoastal dunes in southern Somalia, is described and illustrated. 相似文献
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Alcea mozaffarianii is described and illustrated as a new species from a mountain area in north-western Iran. The differences to similar taxa are discussed. 相似文献
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Stenochironomus falcifer sp. n. is described and figured based on the characters of a male adult. The species was collected in Malaise traps in the Serra Furada State Park (PAESF), in Santa Catarina State, southern Brazil. It can be separated from all other species of Stenochironomus Kieffer, 1919 by its unique thorax pigmentation, with two dark patches on the lateral vittae, brownish postnotum and dark stripes on the scutum, and also by the combination of a narrow, parallel-sided anal point, inferior volsella with a stout apical seta, rounded posterior margin of the tergite IX and green metallic eyes.http://zoobank.org/urn:lsid:zoobank.org:act:3646E02D-7E3F-487A-BED1-A7937AFF8040 相似文献
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The breeding system, floral morphology, morph frequency, biomass allocation to floral whorls, pollination and reproductive efficiency were examined in four distylous and three monomorphic Melochia species. Monomorphic species were self-compatible and distylous species were self-incompatible. Flowers of homomorphic species were longer than those of distylous species. Herkogamy was significantly higher in pin than in thrum morphs of the two distylous species, and monomorphic species exhibited the lowest values of herkogamy. Pollen/ovule ratios were similar between monomorphic and dimorphic species, irrespective of the self-incompatibility level. Biomass allocation to flowers was biased toward non-sexual structures, attraction and support. Androecium biomass and androecium/gynoecium biomass ratio were larger in thrum than in pin flowers of distylous species indicating maleness in the thrum morph and femaleness in the pin morph. There was no clear difference between fruit set of monomorphic and dimorphic species; however, the greatest fruit set was found in the monomorphic species, M. pyramidata, which is a self-compatible species. Fruit set was significantly higher in pin than in thrum morphs in three out four distylous species and fecundity was only significantly higher in pin morphs of M. caracasana and M. parvifolia. Melochia species have generalist pollination systems. According to the taxonomic classes and number of pollinator species, M. caracasana and M. parvifolia have similar generalist pollination systems. Our comparative analyses of the characters between floral morphs of distylous species and the relationship with these characters in monomorphic species allow divergences and similarities to be established and different evolutionary trends to be postulated in the breeding systems of Melochia species. Specifically, M. parvifolia and M. caracasana are apparently biased toward monomorphy and dioecy, respectively. 相似文献
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Medri C Ruas EA Ruas CF Medri PS Medri ME Ruas PM 《Genetics and molecular research : GMR》2011,10(4):3186-3198
The Tibagi River, located in southern Brazil, is associated with a significant degree of environmental heterogeneity, along its 550 km extension. There is concern about the integrity of this river's ecosystem, as human interference has been increasing. Aegiphila sellowiana (Lamiaceae) is an important pioneer tree species, commonly found near rivers; the fruit is consumed by avifauna. We studied this species along three ecological gradients, comprising the upper, middle, and lower regions of the Tibagi River basin. The genetic structure of nine subpopulations of A. sellowiana distributed along these gradients was investigated using RAPDs. Moderate levels of gene diversity (ranging from 0.091 to 0.132) were identified, inferred by a traditional approach and a Bayesian model-based method. The F-statistic, G(ST) parameters and molecular variance analysis showed high genetic differentiation among the three regions (39.5 to 50.26%). Analysis of molecular variance revealed high levels of genetic variation between populations (50.26%), while lower values of genetic variation (ranging from 9.56 to 16.35%) were seen between subpopulations within the upper, middle, and lower regions of the Tibagi River basin. The validity of these results was confirmed by principal coordinate analysis. Linear regression analysis showed significant correlations (r = 0.621, P = 0.0001) between the genetic and geographical distances. The differences observed in genetic variation between regions are probably due to habitat fragmentation; for conservation purposes, we recommend that at least one subpopulation from each region of the Tibagi River should be maintained. 相似文献
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Mats Thulin 《Nordic Journal of Botany》1999,19(2):199-208
Pavonia friisii , sp. nov., from south-eastern Ethiopia and south-central and southern Somalia, P. nigrescens , sp. nov., from south-central and southern Somalia, P. matteiana , sp. nov., from south-central Somalia, P. longipilosa , sp. nov., from eastern Ethiopia, P. rotundifolia , sp. nov., from eastern Ethiopia and northern and central Somalia, P. marginata , sp. nov., from central Somalia, and P. paucibracteata , sp. nov., from central Somalia, are described and illustrated. 相似文献
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Robert A. Klips 《American journal of botany》1995,82(11):1463-1472
Hibiscus dasycalyx is a rare eastern Texas endemic that shares key morphologic traits with two widespread sympatric congeners, H. laevis and H. moscheutos. Working with an initial hypothesis that these taxa were possible ancestors of the endemic through diploid hybridization speciation, a ten-enzyme electrophoretic screening was conducted to determine whether H. dasycalyx exhibits a hybrid genetic profile. The three taxa share predominant alleles for all enzyme systems except ADH, GPI, and PGM, for which H. dasycalyx and H. laevis display generally identical banding patterns that differ from those of H. moscheutos. An analysis of diagnostic leaf shape and calyx pubescence features of eastern Texas H. laevis revealed substantial variation among populations, including forms intermediate between typical H. laevis and H. dasycalyx. In greenhouse hand-pollinations, H. dasycalyx plants serving as ovule parents were freely compatible with H. laevis. Due to the possession of identical isozymes, the occurrence of morphologically intermediate populations where the species cooccur and exhibit an apparent lack of reproductive isolation, the endemic H. dasycalyx may be best regarded as a subspecies or variety of H. laevis, the taxon it most resembles morphologically. Conservation efforts should consider the potential effects of contaminating gene flow with typical H. laevis. 相似文献
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Anathi Magadlela Marí a A. P rez-Fern ndez Aleysia Kleinert L anne L. Dreyer Alex J. Valentine 《Journal of Plant Ecology》2016,9(6):752
Aims In Mediterranean-type ecosystem, the Cape Fynbos, legumes may be able to switch between soil N and atmospheric N 2 sources during growth to adjust the carbon costs of N acquisition. This study investigated the utilization of different inorganic N sources by Virgilia divaricata, a native legume from the Mediterranean-type ecosystem of the Cape Floristic Region.Methods Plants were cultivated in sterile quartz sand, supplied with 25% strength Long Ashton nutrient solution, modified to contain 500 μM Phosphate. At the phosphate level (500 μM), plants were treated with 500 μM NH 4 NO 3 (treatment named N), or grown in N-free nutrient solution and inoculated with effective Burkholderia sp. (Bact.) or treated with combined N sources (500 μM NH 4 NO 3) and inoculated with effective Burkholderia sp. (N+Bact.).Important findings The application of NH 4 NO 3 to the legumes resulted in a greater increase in plant dry matter. Carbon construction costs were higher in plants that were supplied with mineral and symbiotic N sources. Maximum photosynthetic rates per leaf area was maintained, irrespective of the N sources. Although the plant roots were nodulated, the plant dependence on N 2 fixation decreased with addition of N. Roots and nodules of the plants solely reliant on N 2 fixation showed an increase in glutamine content. These results show that V. divaricata is highly adapted for growth at the forest margin. Fynbos and possibly anthropic soils by utilizing both atmospheric and soil N sources. 相似文献
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The mature seeds ofHampea nutricia are glabrous, ovoid, arillate and dark tan in colour. Longitudinal streaks on the seed surface correspond to the underlying integumentary vascular strands. Testa and tegmen are derived from the outer and inner integuments, respectively. The outer epidermis of the tegmen forms a palisade-like macrosclereid layer, the inner epidermis a fringe layer. The endosperm is single-layered and also fills the space between the two cotyledons. The embryo is nearly straight, gland-dotted; it has asymmetrical and folded cotyledons, and gossypol ducts. Systematic position ofHampea is discussed and its placement inMalvaceae is supported. 相似文献
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Mats Thulin 《Nordic Journal of Botany》1999,19(4):421-425
Sida floccosa , sp. nov., from eastern Ethiopia and north-western Somalia, S. ogadensis , sp. nov., from eastern Ethiopia and central Somalia, 5. calliantha , sp. nov., from coastal dunes in southern Somalia, and S. longipedicellata sp. nov., from coastal dunes and sandy plains in central and south-central Somalia, are described and illustrated. 相似文献
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Seventeen species ofHibiscus sectionFurcaria are native to the New World, of which 12 (one diploid, nine tetraploids, one octoploid and one decaploid) have been studied cytotaxonomically. New chromosome counts (2n=4x=72) are reported forH. cucurbitaceus, H. flagelliformis, H. kitaibelifolius, andH. laxiflorus. Seventeen types of tetraploid interspecific hybrids (seven new to this study) all showed complete meiotic chromosome homology (genome formulaGGPP) and normal floral development. That all hybrids were nevertheless almost completely sterile suggests a cytoplasmic component to the genetic differentiation of the species. The diversification of the tetraploid species in habits, habitats and geographical ranges is considerable, despite their similar genome constitutions. A key to 17 native and four introduced African species is presented.Hibiscus cerradoensis sp. nov. is described. 相似文献
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Domingues R Machado MA Forzza RC Melo TD Wohlres-Viana S Viccini LF 《Genetics and molecular research : GMR》2011,10(4):2482-2491
Pitcairnia albiflos is a Bromeliaceae species endemic to Brazil that has been included as data-deficient in the extinction risk list of Brazilian flora. We analyzed genetic variability in P. albiflos populations using RAPD markers to investigate population structure and reproductive mechanisms and also to evaluate the actual extinction risk level of this species. Leaves of 56 individuals of P. albiflos from three populations were collected: Urca Hill (UH, 20 individuals), Chacrinha State Park (CSP, 24 individuals) and Tijuca National Park (TNP, 12 individuals). The RAPD technique was effective in characterizing the genetic diversity in the P. albiflos populations since it was possible to differentiate the populations and to identify exclusive bands for at least two of them. Even if there is low genetic diversity among them (CSP-UH = 0.463; CSP-TNP = 0.440; UH-TNP = 0.524), the populations seem to be isolated according to the low genetic diversity observed within them (H(pop) CSP = 0.060; H(pop) UH = 0.042; H(pop) TNP = 0.130). This fact might be the result of clonal and self-reproduction predominance and also from environmental degradation around the collection areas. Consequently, it would be important to protect all populations both in situ and ex situ to prevent the decrease of genetic variability. The low genetic variability among individuals of the same population confirms the inclusion of this species as critically endangered in the risk list for Brazilian flora. 相似文献