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1.
Braz. j. biol ; 84: e249230, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345556

RESUMO

Abstract The presence of weeds in areas of agricultural activities is a hinderance to the development of these activities. It is important to take advantage of the vast open spaces suitable for agriculture and provide food security for humans, and also it is an important indicator for determining the feasibility of growing crops, benefiting from yield and determining the percentage of loss, clearing fields through agricultural practices, that protect crops from weed attack and agricultural practice method must be followed that will reduce weed presence. This study was conducted during the years 2018 to 2020 to evaluate Portulacaceae of Flora in the Taif area in the Kingdom of Saudi Arabia at different altitudes (Area 1 =1700 m, Area 2 =1500 m, Area 3 =1500 m, Area 4 =500 m ِ Area 5 = 2200 m, and Area 6 = 2200 m). The results show that there were 2,816 individuals of Portulaca oleracea weed, with the highest density found in A 1, followed by A 2, while in A 5 and A 6, no weeds were recorded. The highest density of weeds were in the Pomegranate fields, followed by Grape fields. The lowest density was found in A man field. The results of this study will help to take the necessary measures to combat weeds and its management in areas of agricultural activity, while more studies are needed to survey the ecology of weeds of Taif in The Kingdom of Saudi Arabia.


Resumo A presença de plantas daninhas em áreas de atividades agrícolas é um entrave ao desenvolvimento dessas atividades. É importante aproveitar os vastos espaços abertos adequados para a agricultura e dar segurança alimentar para o homem. Também é um indicador importante para determinar a viabilidade de cultivo de lavouras, beneficiando-se da produtividade e determinando o percentual de perda, desmatando campos agrícolas, práticas que protegem as lavouras do ataque de ervas daninhas, e métodos de práticas agrícolas devem ser seguidos para reduzir a presença de ervas daninhas. Este estudo foi realizado durante os anos de 2018 a 2020 para avaliar Portulacaceae de flora na área de Taif, no Reino da Arábia Saudita, em diferentes altitudes (Área 1 = 1.700 m, Área 2 = 1.500 m, Área 3 = 1.500 m, Área 4 = 500 m, Área 5 = 2.200 m, e Área 6 = 2.200 m). Os resultados mostram que houve 2.816 indivíduos de planta daninha Portulaca oleracea, com a maior densidade encontrada em A 1, seguida de A 2, enquanto em A 5 e A 6, nas plantas daninhas foram registrados. A maior densidade de ervas daninhas estava nos campos de romã, seguido pelos campos de uva. A densidade mais baixa foi encontrada no campo A man. Os resultados deste estudo ajudarão a tomar as medidas necessárias para combater as ervas daninhas e seu manejo em áreas de atividade agrícola, enquanto mais estudos são necessários para levantar a ecologia das ervas daninhas de Taif na Arábia Saudita.


Assuntos
Humanos , Portulacaceae , Arábia Saudita , Produtos Agrícolas , Agricultura , Plantas Daninhas
2.
Braz J Biol ; 84: e252836, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35195168

RESUMO

The bioecology and infestation aspects of Neotuerta platensis Berg, 1882 (Lepidoptera: Noctuidae) on plants are poorly known. This insect fed on the leaves of common purslane, Portulaca oleracea L. (Portulacaceae) for two consecutive years, which triggered its study in the following five years in Januária, Minas Gerais State, Brazil. The objective of this work was to study the bioecology and infestation aspects of N. platensis on P. oleracea plants in the field and laboratory. The mean duration (± SD) of the egg, larva and pupa stages was 3.6 ± 0.89, 11.5 ± 2.81 and 10.7 ± 1.97 days, respectively. The mean numbers of egg masses and eggs per female (± SD) were 3.8 ± 1.16 and 891.6 ± 116.83, respectively. The percentage of infested plants was 59, 74, 0, 78 and 75% and the mean numbers of larvae per plant (± SD) ranged from 0.7 ± 0.45 to 1.6 ± 0.49 individuals, respectively from 2015 to 2019. Neotuerta platensis larvae infested P. oleracea plants in four out of five years evaluated.


Assuntos
Lepidópteros , Mariposas , Portulaca , Portulacaceae , Animais , Brasil , Humanos , Larva
3.
Braz J Biol ; 84: e249230, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34730697

RESUMO

The presence of weeds in areas of agricultural activities is a hinderance to the development of these activities. It is important to take advantage of the vast open spaces suitable for agriculture and provide food security for humans, and also it is an important indicator for determining the feasibility of growing crops, benefiting from yield and determining the percentage of loss, clearing fields through agricultural practices, that protect crops from weed attack and agricultural practice method must be followed that will reduce weed presence. This study was conducted during the years 2018 to 2020 to evaluate Portulacaceae of Flora in the Taif area in the Kingdom of Saudi Arabia at different altitudes (Area 1 =1700 m, Area 2 =1500 m, Area 3 =1500 m, Area 4 =500 m ِ Area 5 = 2200 m, and Area 6 = 2200 m). The results show that there were 2,816 individuals of Portulaca oleracea weed, with the highest density found in A 1, followed by A 2, while in A 5 and A 6, no weeds were recorded. The highest density of weeds were in the Pomegranate fields, followed by Grape fields. The lowest density was found in A man field. The results of this study will help to take the necessary measures to combat weeds and its management in areas of agricultural activity, while more studies are needed to survey the ecology of weeds of Taif in The Kingdom of Saudi Arabia.


Assuntos
Portulacaceae , Agricultura , Produtos Agrícolas , Humanos , Plantas Daninhas , Arábia Saudita
4.
Integr Comp Biol ; 59(3): 517-534, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31161205

RESUMO

Australian Calandrinia has radiated across the Australian continent during the last 30 Ma, and today inhabits most Australian ecosystems. Given its biogeographic range and reports of facultative Crassulacean acid metabolism (CAM) photosynthesis in multiple species, we hypothesized (1) that CAM would be widespread across Australian Calandrinia and that species, especially those that live in arid regions, would engage in strong CAM, and (2) that Australian Calandrinia would be an important lineage for informing on the CAM evolutionary trajectory. We cultivated 22 Australian Calandrinia species for a drought experiment. Using physiological measurements and δ13C values we characterized photosynthetic mode across these species, mapped the resulting character states onto a phylogeny, and characterized the climatic envelopes of species in their native ranges. Most species primarily utilize C3 photosynthesis, with CAM operating secondarily, often upregulated following drought. Several phylogenetically nested species are C3, indicating evolutionary losses of CAM. No strong CAM was detected in any of the species. Results highlight the limitations of δ13C surveys in detecting C3+CAM phenotypes, and the evolutionary lability of C3+CAM phenotypes. We propose a model of CAM evolution that allows for lability and reversibility among C3+CAM phenotypes and C3 and suggest that an annual life-cycle may preclude the evolution of strong CAM.


Assuntos
Evolução Biológica , Traços de História de Vida , Fotossíntese , Portulacaceae/metabolismo , Austrália
5.
J Exp Bot ; 70(22): 6581-6596, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31111894

RESUMO

Crassulacean acid metabolism (CAM) has evolved as a water-saving strategy, and its engineering into crops offers an opportunity to improve their water use efficiency. This requires a comprehensive understanding of the regulation of the CAM pathway. Here, we use the facultative CAM species Talinum triangulare as a model in which CAM can be induced rapidly by exogenous abscisic acid. RNA sequencing and metabolite measurements were employed to analyse the changes underlying CAM induction and identify potential CAM regulators. Non-negative matrix factorization followed by k-means clustering identified an early CAM-specific cluster and a late one, which was specific for the early light phase. Enrichment analysis revealed abscisic acid metabolism, WRKY-regulated transcription, sugar and nutrient transport, and protein degradation in these clusters. Activation of the CAM pathway was supported by up-regulation of phosphoenolpyruvate carboxylase, cytosolic and chloroplastic malic enzymes, and several transport proteins, as well as by increased end-of-night titratable acidity and malate accumulation. The transcription factors HSFA2, NF-YA9, and JMJ27 were identified as candidate regulators of CAM induction. With this study we promote the model species T. triangulare, in which CAM can be induced in a controlled way, enabling further deciphering of CAM regulation.


Assuntos
Ácido Abscísico/metabolismo , Ácidos Carboxílicos/metabolismo , Metaboloma/genética , Portulacaceae/genética , Portulacaceae/metabolismo , Ácido Abscísico/farmacologia , Metabolismo dos Carboidratos/efeitos dos fármacos , Metabolismo dos Carboidratos/genética , Análise por Conglomerados , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Portulacaceae/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transcriptoma/genética
6.
Protoplasma ; 256(3): 805-814, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30604246

RESUMO

The clade ACPT (Anacampserotaceae, Cactaceae, Portulacaceae, and Talinaceae) is the most diverse lineage of the subordem Cactineae. The relationships between these families are still uncertain, with different topologies suggested by phylogenetic analyses with several combinations of markers. Different basic numbers (x) have been suggested for each family and for the subord, often in a contestable way. Comparative cytogenetic has helped to understand the evolutionary relationships of phylogenetically poorly resolved groups, as well as their mechanisms of karyotype evolution. The karyotype evolution in representatives of Cactineae was analyzed, focusing on the ACPT clade, through the analysis of chromosome number in a phylogenetic bias. The phylogeny obtained showed a well-resolved topology with support for the monophyly of the five families. Although a chromosomal number is known for less than 30% of the Cactineae species, the analyses revealed a high karyotype variability, from 2n = 8 to 2n = 110. The analysis of character reconstruction of the ancestral haploid numbers (p) suggested p = 12 for Cactineae, with distinct basic numbers for the clade family ACPT: Cactaceae and Montiaceae (p = 11), Talinaceae (p = 12), and Anacampserotaceae and Portulacaceae (p = 9). Talinaceae, Anacampserotaceae, and Cactaceae were stable, while Portulaca and Montiaceae were karyotypically variable. The chromosome evolution of this group was mainly due to events of descending disploidy and poliploidy. Our data confirm that the low phylogenetic resolution among the families of the ACPT clade is due to a divergence of this clade in a short period of time. However, each of these families can be characterized by basic chromosome numbers and unique karyotype evolution events.


Assuntos
Cactaceae/classificação , Cactaceae/genética , Caryophyllales/classificação , Caryophyllales/genética , Citogenética , Filogenia , Portulacaceae/classificação , Portulacaceae/genética , Cromossomos de Plantas/genética , Modelos Biológicos
7.
Biomed Pharmacother ; 105: 434-439, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29879627

RESUMO

Portulacaoleraceal (POL) has been widely used as an edible plant and a folk medicine in many countries, due to its several health benefits. This study examined the effects of POL on trinitrobenzene sulfonic acid (TNBS)-induced colitis via enema administration. Sixty male Sprague-Dawley rats were randomly divided into five groups: untreated, TNBS, TNBS + POL 10 g/kg, TNBS + POL 5 g/kg and TNBS + POL 2.5 g/kg groups. Rats were subjected to enema treatment once a day for 10 consecutive days with POL extract or distilled water after induction of TNBS. The changes of body weight, histological parameters, myeloperoxidase (MPO), superoxide dismutase (SOD), nitric oxide synthase activity (NOS), malondialdehyde (MDA) and nitric oxide (NO) levels in colon tissues were investigated. After POL extract treatment, body weights of rats significantly increased, macroscopic and microscopic damage scores reduced, MPO and NOS activity, as well as MDA and NO level significantly decreased, while SOD activity increased in a dose-dependent manner in the TNBS + POL groups compared with the TNBS group. Our results demonstrated that POL enema treatment attenuated pathologic changes of TNBS-induced colitis in rats through restoring colonic damage and reducing inflammatory response in the intestine. Thus, POL enema might be considered as a potential effective treatment for ulcerative colitis patients.


Assuntos
Colite/induzido quimicamente , Colite/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Portulacaceae/química , Animais , Peso Corporal/efeitos dos fármacos , Colite/patologia , Colo/efeitos dos fármacos , Colo/patologia , Masculino , Malondialdeído/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Peroxidase/metabolismo , Extratos Vegetais/farmacologia , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Ácido Trinitrobenzenossulfônico
8.
Am J Bot ; 105(3): 536-548, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29672830

RESUMO

PREMISE OF THE STUDY: Species formation is an intuitive endpoint of reproductive isolation, but circumscribing taxa that arise during speciation can be difficult because of gene flow, morphological continuity, hybridization or polyploidization, and low sequence variation among newly diverged lineages. Nonetheless, species complexes are ubiquitous, and their classification is essential for understanding how diversity influences ecosystem function. METHODS: We used modern sequencing technology to identify lineages of perennial Claytonia L. and assessed correspondence between genetic lineages and morphological/ecological variation. Subsets of 18 taxa from 63 populations were used for (a) lineage discovery using network and coalescent analyses, (b) leaf shape analyses using elliptical Fourier analysis and ordination, and (c) ecological analyses (soil chemistry, climate) using ANOVA and ordination. KEY RESULTS: Samples mainly aggregated into groups representing each of the previously recognized species in each of the genetic data sets. Compared to the double-digest restriction-site-associated DNA sequencing data set, genome skimming data provided more resolution and further opportunity to probe into patterns of nuclear and chloroplast genome diversity. Morphological and ecological associations are significantly different (albeit intergrading) among the taxa investigated. A new species, Claytonia crawfordii, is described based on morphological data presented here. CONCLUSIONS: Genetic data presented in this study provide some of the first insights into phylogenetic relationships among recently diverged perennial Claytonia and are suggestive of past hybridization among caudicose and tuberous species. Given prior difficulties in understanding species boundaries among newly diverged plant lineages, this case study demonstrates the revolutionary breakthrough for systematics research that high throughput sequencing represents.


Assuntos
Ecologia , Evolução Molecular , Especiação Genética , Hibridização Genética , Filogenia , Folhas de Planta/anatomia & histologia , Portulacaceae/genética , Sequência de Bases , Classificação , Clima , DNA de Plantas/análise , Ecossistema , Fluxo Gênico , Variação Genética , Genoma de Cloroplastos , Genoma de Planta , Genômica/métodos , Fenótipo , Poliploidia , Portulacaceae/anatomia & histologia , Isolamento Reprodutivo , Análise de Sequência de DNA , Solo/química
9.
Ann Bot ; 121(7): 1333-1342, 2018 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-29596562

RESUMO

Background and Aims: Crassulacean acid metabolism (CAM) can be induced by salinity, thus conferring the plant higher water-use efficiency. Talinum triangulare does not frequently encounter salt in its natural habitat but is cultivated in soils that may become salinized. Here we examined whether plants of T. triangulare can grow in saline soils and show salt-induced CAM. Methods: Leaf gas exchange, carbon isotopic ratio (δ13C), nocturnal acid accumulation (ΔH+), water relations, photosynthetic pigment and mineral contents, leaf anatomy and growth were determined in greenhouse in plants irrigated with 0, 150, 300 and 400 mm NaCl. Key Results: Salinity reduced gas exchange and induced CAM, ΔH+ reaching 50.2 µmol H+ g-1 fresh mass under 300 mm NaCl. No nocturnal CO2 uptake, but compensation, was observed. Values of δ13C were lowest under 0 and 400 mm NaCl, and highest under 150 and 300 mm. The difference in osmotic potential (ψs) between control and treated plants averaged 0.45 MPa for the three [NaCl] values, the decrease in ψs being accounted for by up to 63 % by Na+ and K+. Pigment contents were unaffected by treatment, suggesting lack of damage to the photosynthetic machinery. Changes in stomatal index with unchanged stomatal density in newly expanded leaves suggested inhibited differentiation of epidermal cells into stomata. Whole-leaf and parenchymata thickness increased under 150 and 300 mm NaCl. Only plants irrigated with 400 mm NaCl showed reductions in biomass (stems, 41 %; reproductive structures, 78 %). The K/Na molar ratio decreased with [NaCl] from 2.0 to 0.4. Conclusions: The operation of CAM in the recycling mode was evidenced by increased ΔH+ with no nocturnal CO2 uptake. Talinum triangulare can be classified as a halo-tolerant species based on its low K/Na molar ratio under salinity and the relatively small reduction in growth only at the highest [NaCl].


Assuntos
Portulacaceae/metabolismo , Plantas Tolerantes a Sal/metabolismo , Folhas de Planta/metabolismo , Transpiração Vegetal , Tolerância ao Sal , Água/metabolismo
10.
Diabetes Metab Syndr ; 12(6): 831-837, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28951062

RESUMO

AIM: Cardiovascular diseases (CVDs) and diabetes mellitus (DM) are some of the leading causes of death in the world, and diet has roles in their etiology. This research study therefore investigates the glycemic index (GI) of soy flour fortified whole wheat meal (SFFWWM) consumed with Talinum triangulare (gbure) soup and the effects of the meal on the lipid profiles of the test human subjects. METHODS: The control human subjects and test human subjects were fed D-glucose (DG) and whole wheat meal (WWM) with Talinum triangulare soup respectively on the first day of the experiment, and SFFWWM with the same soup the next day (for test subjects only) after 10-12h overnight fasting. Blood glucose levels of the subjects were taken before and 2h after meals' consumption at 30min interval and blood samples collected for lipid profiles evaluations. RESULTS: The result of the study showed that; SFFWWM consumed with Talinum trianguilare soup has a non-significant lower GI than WWM consumed with the same soup, but a significant lower GI than DG at (P<0.05). Furthermore, there was no significant difference in lipid profiles of the test human subjects between when they consumed WWM and SFFWWM with the soup however, SFFWWM reduced TC, TG, LDL-C and VDL-C and increased HDL-C and TP than WMM at (P<0.05). In addition, GI is positively correlated with TC, TG, LDL-C and VLDL-C, but is negatively correlated with TP and HDL-C. CONCLUSION: It can therefore be concluded that; fortifying WWM with soy flour would reduce the risk factors of CVDs and DM, the diseases recently claiming thousands of today.


Assuntos
Índice Glicêmico , Lipídeos/sangue , Portulacaceae , Alimentos de Soja , Triticum , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus/prevenção & controle , Feminino , Humanos , Masculino
11.
Evolution ; 72(1): 202-210, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29055134

RESUMO

Geographical variation in pollinators visiting a plant can produce plant populations adapted to local pollinator environments. We documented two markedly different pollinator climates for the spring ephemeral wildflower Claytonia virginica: in more northern populations, the pollen-specialist bee Andrena erigeniae dominated, but in more southern populations, A. erigeniae visited rarely and the bee-fly Bombylius major dominated. Plants in the northern populations experienced faster pollen depletion than plants in southern populations. We also measured divergent pollen-related plant traits; plants in northern populations produced relatively more pollen per flower and anther dehiscence was more staggered than plants in southern populations. These plant traits might function to increase pollen dispersal via the different pollen vectors.


Assuntos
Abelhas/fisiologia , Portulacaceae/fisiologia , Animais , Abelhas/classificação , Pólen , Polinização
13.
Pesqui. vet. bras ; 37(8): 785-789, Aug. 2017. ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-895501

RESUMO

Descreve-se um surto de intoxicação aguda em bovinos causado pela ingestão de Portulaca elatior na região nordeste do Brasil. O surto resultou da ingestão a partir da administração da planta no cocho pelo criador para os bovinos. Quatro de cinco bovinos foram intoxicados e dois morreram. Os sinais clínicos incluíram dor abdominal, tremores musculares, intensa salivação, timpanismo moderado e desidratação. O curso clínico da doença variou de 10 a 18 horas. Os achados macroscópicos incluíram desidratação, avermelhamento das mucosas dos pré-estômagos, abomaso e intestinos, além de ulceração da mucosa ruminal. Nos dois casos foi notada a presença de fragmentos de Portulaca no interior do rúmen. Os achados histológicos foram de degeneração e necrose das camadas superficiais do epitélio dos pré-estômagos, necrose e inflamação da mucosa intestinal e necrose linfoide. As atividades de AST e GGT estavam dentro dos valores de normalidade. O diagnóstico de intoxicação associado à ingestão de P. elatior foi baseado na epidemiologia, sinais clínicos e lesões. A ausência de informação sobre a toxicidade de P. elatior foi a principal causa para a ocorrência da intoxicação acidental.(AU)


An outbreak of acute poisoning in cattle caused by the ingestion of Portulaca elatior occurred in the northeastern Brazil. The outbreak resulted from ingestion of the plant provided by the farmer. Four out of five cattle were poisoned and two died. Clinical signs included abdominal pain, muscle trembling, intense salivation, mild bloat and dehydration. The course of the disease ranged from 10 to 18 hours. Gross findings included dehydration, reddening of the mucosa of forestomachs, abomasum, and intestine, with ulcerations of the ruminal mucosa. The presence of Portulaca leaves in the rumen was noted in both cases. The main histologic lesions were superficial to full thickness degeneration and necrosis of the stratified epithelium lining the forestomachs, necrosis and inflammation of the intestinal mucosa, and lymphoid necrosis. The serum activities of AST and GGT and serum were within normal ranges. The diagnosis of poisoning associated with ingestion of P. elatior was based on the epidemiology, clinical signs and lesions. The lack of information about the toxicity of P. elatior was the main cause for the accident of poisoning.(AU)


Assuntos
Animais , Bovinos , Intoxicação por Plantas/veterinária , Rúmen , Portulacaceae/toxicidade , Necrose/veterinária , Plantas Tóxicas
14.
Evolution ; 71(8): 1960-1969, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28598499

RESUMO

The geographic distributions of polyploids suggest they can have distinct and sometimes broader niches compared to diploids. However, relatively few field experiments have investigated whether range differences are associated with local adaptation or reflect other processes, such as dispersal limitation. In three years of transplants across the elevational ranges of five cytotypes in the Claytonia perfoliata complex, we found evidence for local adaptation. In at least one study year germination was higher within the natural range for each cytotype, and four of the five cytotypes attained larger biomass within their natural range. Fitness within and beyond range varied across years, with two instances of cytotypes showing higher fitness beyond the range, highlighting a potential role of temporal variability in cytotype differentiation. Polyploids as a group did not outperform diploids, but the cytotype with highest fitness across environments was a hexaploid reported to be invasive. Our results suggest that differences in geographic ranges within the C. perfoliata complex reflect local adaptation of cytotypes. Although we did not find a general polyploid advantage, our findings support the idea that occasional polyploid cytotypes exhibit high fitness relative to other cytotypes, and contribute to growing evidence supporting ecological differentiation of cytotypes within polyploid complexes.


Assuntos
Poliploidia , Portulacaceae/genética , Aclimatação , Adaptação Fisiológica , Diploide , Ecologia , Meio Ambiente
15.
Insect Sci ; 24(4): 640-646, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27028188

RESUMO

Inert dusts are an early form of insecticide which is still in use. One of the most common inert dusts is volcanic ash. In order to study the reaction of rangeland grasshoppers, Dichroplus vittigerum (Acrididae) and a katydid, Burgilis mendosensis (Phaneropteridae), to the presence of volcanic ash in their food sources and how this reaction changed as a function of time, we conducted paired preference tests between clean leaves of their preferred host plant and leaves exposed to volcanic ash of different grain size. The behavioral response was measured as the rating on the Thurstonian preference scale of leaves with ash in relation to clean leaves. The results showed that the avoidance of volcanic ash increased as a function of time in both species. Both species studied are occasionally exposed to volcanic activity, and come from an area in which a volcanic eruption had recently occurred. As their populations did not decrease after the ash fall, we propose that some behavioral responses such as avoidance of places with ash, works as tolerance mechanism to inert dusts exposure.


Assuntos
Preferências Alimentares , Gafanhotos/fisiologia , Tamanho da Partícula , Erupções Vulcânicas/efeitos adversos , Animais , Argentina , Folhas de Planta , Portulacaceae , Taraxacum , Fatores de Tempo
16.
Glob Chang Biol ; 22(5): 1779-93, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26833694

RESUMO

Climate change has had numerous ecological effects, including species range shifts and altered phenology. Altering flowering phenology often affects plant reproduction, but the mechanisms behind these changes are not well-understood. To investigate why altering flowering phenology affects plant reproduction, we manipulated flowering phenology of the spring herb Claytonia lanceolata (Portulacaceae) using two methods: in 2011-2013 by altering snow pack (snow-removal vs. control treatments), and in 2013 by inducing flowering in a greenhouse before placing plants in experimental outdoor arrays (early, control, and late treatments). We measured flowering phenology, pollinator visitation, plant reproduction (fruit and seed set), and pollen limitation. Flowering occurred approx. 10 days earlier in snow-removal than control plots during all years of snow manipulation. Pollinator visitation patterns and strength of pollen limitation varied with snow treatments, and among years. Plants in the snow removal treatment were more likely to experience frost damage, and frost-damaged plants suffered low reproduction despite lack of pollen limitation. Plants in the snow removal treatment that escaped frost damage had higher pollinator visitation rates and reproduction than controls. The results of the array experiment supported the results of the snow manipulations. Plants in the early and late treatments suffered very low reproduction due either to severe frost damage (early treatment) or low pollinator visitation (late treatment) relative to control plants. Thus, plants face tradeoffs with advanced flowering time. While early-flowering plants can reap the benefits of enhanced pollination services, they do so at the cost of increased susceptibility to frost damage that can overwhelm any benefit of flowering early. In contrast, delayed flowering results in dramatic reductions in plant reproduction through reduced pollination. Our results suggest that climate change may constrain the success of early-flowering plants not through plant-pollinator mismatch but through the direct impacts of extreme environmental conditions.


Assuntos
Polinização , Portulacaceae/fisiologia , Mudança Climática , Colorado , Flores/crescimento & desenvolvimento , Flores/fisiologia , Portulacaceae/crescimento & desenvolvimento , Reprodução , Estações do Ano
17.
Fitoterapia ; 109: 169-73, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26773210

RESUMO

The first chemical examination of roots of the traditionally used medicinal plant Talinum triangulare (Portulacaceae) from Nigeria led to the isolation of two new C-methylated flavonoids, 5,6-dimethoxy-7-hydroxy-8-methyl-flavone (1), 5,6-dimethoxy-8-methyl-2-phenyl-7H-1-benzopyran-7-one (2), and one new α-pyrone derivative, 4-methoxy-6-(2-hydroxy-4-phenylbutyl)-2H-pyran-2-one (3), along with thirteen known compounds, including nine amides (4-12), indole-3-carboxylic acid (13), p-hydroxy benzoic acid (14), and two steroids (15-16). Their structures were elucidated by extensive spectroscopic measurements including 1D, 2D NMR, MS, and by comparison with the literature. All isolated compounds were screened for their cytotoxic and antifungal activities. However, none of them showed significant activity.


Assuntos
Flavonoides/química , Raízes de Plantas/química , Portulacaceae/química , Pironas/química , Animais , Linhagem Celular Tumoral , Flavonoides/isolamento & purificação , Camundongos , Estrutura Molecular , Nigéria , Plantas Medicinais/química , Pironas/isolamento & purificação
18.
Ecol Lett ; 18(4): 336-46, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25728390

RESUMO

Alien plant species are known to have a wide range of impacts on recipient communities, from resident species' exclusions to coexistence with resident species. It remains unclear; however, if this variety of impacts is due to different invader strategies, features of recipient communities or both. To test this, we examined multiple plant invasions of a single ecosystem in southwestern Australia. We used extensive community data to calculate pairwise segregation between target alien species and many co-occurring species. We related segregation to species' positions along community trait hierarchies and identified at least two distinct invasion strategies: 'exploiters' which occupy high positions along key trait hierarchies and reduce local native species diversity (particularly in nutrient-enriched situations), and 'coexisters' who occupy intermediate trait positions and have no discernable impact on native diversity. We conclude that trait hierarchies, linked to measures of competition, can provide valuable insights about the processes driving different invasion outcomes.


Assuntos
Biodiversidade , Ecossistema , Espécies Introduzidas , Plantas/classificação , Característica Quantitativa Herdável , Araliaceae/fisiologia , Asteraceae/fisiologia , Modelos Biológicos , Poaceae/fisiologia , Portulacaceae/fisiologia , Scrophulariaceae/fisiologia , Austrália Ocidental
19.
Food Chem ; 160: 204-8, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24799228

RESUMO

This first phytochemical study of Talinum triangulare Leach (Portulacaceae), also known as 'cariru', which is a commonly consumed food in Northern Brazil, allowed the isolation and structural determination of four new compounds: one acrylamide, 3-N-(acryloyl, N-pentadecanoyl) propanoic acid (5), and three new phaeophytins named (15(1)S, 17R, 18R)-Ficuschlorin D acid (3(1),3(2)-didehydro-7-oxo-17(3)-O-phytyl-rhodochlorin-15-acetic acid), (13), Talichorin A (17R, 18R)-phaeophytin b-15(1)-hidroxy, 15(2),15(3)-acetyl-13(1)-carboxilic acid (14), and (15(1)S, 17R, 18R)-phaeophytin b peroxylactone or (15(1)S, 17R, 18R)-hydroperoxy-ficuschlorin D (16), together with twelve known compounds, including four phaeophytins (11,12, 15 and 17). The structures of the compounds were established on the basis of 1D and 2D NMR, IR, HRESI-MS spectra, including GC-MS, and HPLC-UV analysis, as well as comparisons with the literature data. The CD spectra data analysis were used to define the absolute configuration of phaeophytins 12 (13(2)R, 17R, 18R)-13(2)-hydroxyphaeophytin a, 13 and 16, 15 (15(1)S, 17R, 18R)-3(1),3(2)-didehydro-15(1)-hydroxyrhodochlorin-15-acetic acid δ-lactone-15(2)-methyl-17(3)-phytyl ester and 17 (17R, 18R)-purpurin 18-phytyl ester.


Assuntos
Compostos Fitoquímicos/análise , Portulacaceae/química , Brasil , Clorofila/análise , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Magnoliopsida , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/química , Folhas de Planta/química , Caules de Planta/química , Espectrometria de Massas por Ionização por Electrospray
20.
Environ Sci Pollut Res Int ; 21(14): 8750-64, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24705950

RESUMO

In this study, Talinum triangulare Jacq. (Willd.) treated with different lead (Pb) concentrations for 7 days has been investigated to understand the mechanisms of ascorbate-glutathione metabolisms in response to Pb-induced oxidative stress. Proteomic study was performed for control and 1.25 mM Pb-treated plants to examine the root protein dynamics in the presence of Pb. Results of our analysis showed that Pb treatment caused a decrease in non-protein thiols, reduced glutathione (GSH), total ascorbate, total glutathione, GSH/oxidized glutathione (GSSG) ratio, and activities of glutathione reductase and γ-glutamylcysteine synthetase. Conversely, cysteine and GSSG contents and glutathione-S-transferase activity was increased after Pb treatment. Fourier transform infrared spectroscopy confirmed our metabolic and proteomic studies and showed that amino, phenolic, and carboxylic acids as well as alcoholic, amide, and ester-containing biomolecules had key roles in detoxification of Pb/Pb-induced toxic metabolites. Proteomic analysis revealed an increase in relative abundance of 20 major proteins and 3 new proteins (appeared only in 1.25 mM Pb). Abundant proteins during 1.25 mM Pb stress conditions have given a very clear indication about their involvement in root architecture, energy metabolism, reactive oxygen species (ROS) detoxification, cell signaling, primary and secondary metabolisms, and molecular transport systems. Relative accumulation patterns of both common and newly identified proteins are highly correlated with our other morphological, physiological, and biochemical parameters.


Assuntos
Ácido Ascórbico/metabolismo , Glutationa/metabolismo , Chumbo/toxicidade , Proteínas de Plantas/metabolismo , Portulacaceae/efeitos dos fármacos , Biomarcadores/metabolismo , Cisteína/metabolismo , Eletroforese em Gel Bidimensional , Glutationa Redutase/metabolismo , Magnoliopsida/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Plantas/metabolismo , Portulacaceae/metabolismo , Proteínas/metabolismo , Proteômica , Espécies Reativas de Oxigênio/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Fisiológico , Compostos de Sulfidrila/metabolismo
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