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1.
Braz. J. Pharm. Sci. (Online) ; 58: e201158, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1420464

RESUMO

Abstract Quality of groundwater is threatened due to pollution by industrial, domestic and agricultural waste. A large number of populations are residing in rural areas which are unable to afford high cost water purifiers due to their low income as well as limited awareness. However, limited availability of fresh water has become a critical issue in developing countries. Around 1.2 billion population is deprived of affordable and safe water for their domestic need. Additionally, chemical coagulants which are nowadays being used for water purification pose severe and numerous health hazards to human. Thus utilization of easily accessible natural coagulant for water purification might offer a sustainable, practical and cost effective solution to the current alarming situation in developing countries. Several experimental findings have shown strong efficiency of Moringa oleifera plant extracts obtained from different solvents in the improvement of water quality parameters including physicochemical (such as pH, hardness, turbidity, metallic impurities, total dissolved solid) and biological (E.coli count) parameter. We have also highlighted the limitations and advantages of chemical coagulation in water purification. Altogether, this review summarizes one such miracle tree which has shown significant potential as a natural coagulant and its associated underlying mechanism in water purification process.


Assuntos
Plantas/anatomia & histologia , Coagulantes (Tratamento da Água) , Purificação da Água/instrumentação , Moringa oleifera/efeitos adversos , Água Potável/análise , Extratos Vegetais/efeitos adversos , Custos e Análise de Custo/classificação , Poluição Ambiental/análise , Água Doce/análise
2.
Adv Mater ; 32(48): e2004519, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33079407

RESUMO

Many organisms encapsulate their embryos in hard, protective shells. While birds and reptiles largely rely on mineralized shells, plants often develop highly robust lignocellulosic shells. Despite the abundance of hard plant shells, particularly nutshells, it remains unclear which fundamental properties drive their mechanical stability. This multiscale analysis of six prominent (nut)shells (pine, pistachio, walnut, pecan, hazelnut, and macadamia) reveals geometric and structural strengthening mechanisms on the cellular and macroscopic length scales. The strongest tissues, found in walnut and pistachio, exploit the topological interlocking of 3D-puzzle cells and thereby outperform the fiber-reinforced structure of macadamia under tensile and compressive loading. On the macroscopic scale, strengthening occurs via an increased shell thickness, spherical shape, small size, and a lack of extended sutures. These functional interrelations suggest that simple geometric modifications are a powerful and resource-efficient strategy for plants to enhance the fracture resistance of entire shells and their tissues. Understanding the interplay between structure, geometry, and mechanics in hard plant shells provides new perspectives on the evolutionary diversification of hard seed coats, as well as insights for nutshell-based material applications.


Assuntos
Fenômenos Mecânicos , Plantas/anatomia & histologia , Fenômenos Biomecânicos
3.
PLoS One ; 15(9): e0239588, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32966345

RESUMO

Despite a growing body of evidence concerning accelerated organic degradation at archaeological sites, there have been few follow-up investigations to examine the status of the remaining archaeological materials in the ground. To address the question of archaeo-organic preservation, we revisited the Swedish, Mesolithic key-site Ageröd and could show that the bone material had been subjected to an accelerated deterioration during the last 75 years, which had destroyed the bones in the areas where they had previously been best preserved. To understand why this has happened and to quantify and qualify the extent of the organic degradation, we here analyse the soil chemistry, bone histology, collagen preservation and palaeobotany at the site. Our results show that the soil at Ageröd is losing, or has already lost, its preservative and buffering qualities, and that pH-values in the still wet areas of the site have dropped to levels where no bone preservation is possible. Our results suggest that this acidification process is enhanced by the release of sulphuric acid as pyrite in the bones oxidizes. While we are still able to find well-preserved palaeobotanical remains, they are also starting to corrode through re-introduced oxygen into the archaeological layers. While some areas of the site have been more protected through redeposited soil on top of the archaeological layers, all areas of Ageröd are rapidly deteriorating. Lastly, while it is still possible to perform molecular analyses on the best-preserved bones from the most protected areas, this opportunity will likely be lost within a few decades. In conclusion, we find that if we, as a society, wish to keep this valuable climatic, environmental and cultural archive, both at Ageröd and elsewhere, the time to act is now and if we wait we will soon be in a situation where this record will be irretrievably lost forever.


Assuntos
Arqueologia/métodos , Fósseis/história , Animais , Osso e Ossos/anatomia & histologia , Osso e Ossos/química , Botânica , Colágeno/análise , Conservação dos Recursos Naturais/métodos , Características Culturais/história , Fósseis/anatomia & histologia , História Antiga , Paleontologia , Plantas/anatomia & histologia , Preservação Biológica/história , Datação Radiométrica , Solo/química , Suécia , Áreas Alagadas
4.
Nat Commun ; 11(1): 4519, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908150

RESUMO

The leaf economics spectrum (LES) describes consistent correlations among a variety of leaf traits that reflect a gradient from conservative to acquisitive plant strategies. So far, whether the LES holds in wetland plants at a global scale has been unclear. Using data on 365 wetland species from 151 studies, we find that wetland plants in general show a shift within trait space along the same common slope as observed in non-wetland plants, with lower leaf mass per area, higher leaf nitrogen and phosphorus, faster photosynthetic rates, and shorter leaf life span compared to non-wetland plants. We conclude that wetland plants tend to cluster at the acquisitive end of the LES. The presented global quantifications of the LES in wetland plants enhance our understanding of wetland plant strategies in terms of resources acquisition and allocation, and provide a stepping-stone to developing trait-based approaches for wetland ecology.


Assuntos
Fotossíntese/genética , Folhas de Planta/genética , Plantas/genética , Áreas Alagadas , Nitrogênio/análise , Fósforo/análise , Folhas de Planta/anatomia & histologia , Folhas de Planta/química , Plantas/anatomia & histologia , Plantas/metabolismo
5.
Microsc Res Tech ; 83(4): 345-353, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31789485

RESUMO

Recent field exploration and collections has led to the findings of several new species in Pakistan. Here we reported two new species Ajuga reptance L and Sphagneticola trilobata (L.) Prusk for the first time in Pakistan flora as these species were neither listed in any other literature nor identified before in Pakistan. These species were found as a result of taxonomic studies performed in the year 2019 in District Rawalpindi and Islamabad, Pakistan. Microscopic techniques were used for the confirmation of foliar epidermal and pollen micromorphological features. Detailed study (morphological, palynological, and foliar epidermal) was provided for the correct identification and delimitation of the species using both light and scanning electron microscopy. Morphological results were compared with the flora of Taiwan and China.


Assuntos
Ajuga/anatomia & histologia , Microscopia/métodos , Estômatos de Plantas/ultraestrutura , Plantas/anatomia & histologia , Pólen/ultraestrutura , Tricomas/ultraestrutura , China , Microscopia Eletrônica de Varredura , Paquistão , Plantas/classificação , Taiwan
6.
PLoS One ; 14(3): e0213909, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30870523

RESUMO

Optical methods, as fluorescence microscopy or hyperspectral imaging, are commonly used for plants visualization and characterization. Another powerful collection of optical techniques is the so-called polarimetry, widely used to enhance image contrast in multiple applications. In the botanical applications framework, in spite of some works have already highlighted the depolarizing print that plant structures left on input polarized beams, the potential of polarimetric methods has not been properly exploited. In fact, among the few works dealing with polarization and plants, most of them study light scattered by plants using the Degree of Polarization (DoP) indicator. Other more powerful depolarization metrics are nowadays neglected. In this context, we highlight the potential of different depolarization metrics obtained using the Mueller matrix (MM) measurement: the Depolarization Index and the Indices of Polarimetric Purity. We perform a qualitative and quantitative comparison between DoP- and MM-based images by studying a particular plant, the Hedera maroccana. We show how Mueller-based metrics are generally more suitable in terms of contrast than DoP-based measurements. The potential of polarimetric measurements in the study of plants is highlighted in this work, suggesting they can be applied to the characterization of plants, plant taxonomy, water stress in plants, and other botanical studies.


Assuntos
Botânica/métodos , Plantas/anatomia & histologia , Botânica/instrumentação , Botânica/estatística & dados numéricos , Hedera/anatomia & histologia , Luz , Microscopia de Polarização/métodos , Imagem Óptica/métodos , Folhas de Planta/anatomia & histologia , Espalhamento de Radiação
7.
Microsc Res Tech ; 82(6): 720-730, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30676673

RESUMO

The present study was carried out to investigate the polliniferous bee flora of Lakki Marwat district, Khyber Pakhtunkhwa, Pakistan. A total of 18 species, belonging to 13 different families were identified for the foraging activities of honeybees, namely, Cenchrus biflorus, Cestrum nocturnum, Citrus limon, Combretum indicum, Datura innoxia, Duranta erecta, Hamelia patens, Helianthus annuus, Ipomoea cairica, Luffa aegyptiaca, Nerium oleander, Ocimum basilicum, Parthenium hysterophorus, Pennisetum typhoides, Prosopis cineraria, Prosopis juliflora, Saccharum spontaneum, and Ziziphus jujuba. The identified melliferous flora was collected for the morpho-palynological investigation. Pollen were acetolyzed, measured, and described qualitatively using light microscopy. The pollen types varied from psilate to echinate and colpi from tricolpate to hexacolpate. Quantitative characteristics including polar diameter, equatorial diameter, polar to equatorial ratio, colpi length, colpi width, spine length, spine width, and exine thickness of the pollen were determined and analyzed statistically using software IBM SPSS Statistics 20. The results of the present study highlighted the significance of pollen morphology of the bee flora of the area which may lead to the identification of the potential and useful botanical sources for beekeepers and to check the honey quality marketed from the study area.


Assuntos
Abelhas/fisiologia , Microscopia/métodos , Plantas/anatomia & histologia , Plantas/classificação , Pólen/citologia , Animais , Paquistão , Polinização
8.
PLoS One ; 13(7): e0201175, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30052656

RESUMO

Seed size is a fundamental life-history trait for plants. A seed number/size trade-off is assumed because the resources invested in reproduction are limited; however, such a trade-off is not always observed. This could be a consequence of the method used for testing it, where the null hypothesis is dictated by common statistical practice, rather than being based on any underlying theory. Alternatively, there might be some population- and species-dependent variables that affect resource availability and, in turn, influence the presence and intensity of this trade-off. Using data on 42 herbs from two communities (lowland and alpine) from Southern Norway, we tested the validity of the classical linear model vs. two previously proposed models, based on resource competition, when assessing the existence of this trade-off at different levels. We also evaluated whether some species- (fruit aggregation, ovules/flower) and population-dependent (pollen limitation) variables could affect this trade-off. Classical linear modelling outperformed the other proposed functional models. Significant seed number/size relationships were negative in single-fruited species, whereas they were positive in species with infructescences of one-seeded fruits. Concordantly, fruit organization was the most influencing variable for the intra-specific trade-off in the lowland community. In the alpine community, species suffering higher pollen limitation showed more strongly negative slopes between seed size and seed number at the fruit/infructescence level. Across species, seed size and number were negatively related, although the relationship was significant in only one of the communities. No evidence of trade-off was found at the plant level. Linear models provide a flexible framework that allows coping with the variability in the seed number/size relationship. The emergence of the intra-specific relationship between seed number and size depends on species- and population-dependent variables, related to resource allocation and the pollination environment.


Assuntos
Modelos Biológicos , Plantas/anatomia & histologia , Sementes/anatomia & histologia , Altitude , Ecossistema , Frutas/anatomia & histologia , Modelos Lineares , Análise Multinível , Noruega , Pólen , Reprodução , Especificidade da Espécie
9.
Am J Bot ; 105(7): 1154-1164, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30047984

RESUMO

PREMISE OF THE STUDY: Wildfire changes the demography, morphology, and behavior of plants, and may alter the pollinator community. Such trait changes may drastically alter the outcome of pollination mutualisms on plants; however, the direct role of fire on these mutualisms is poorly known. METHODS: Following a pair of fires in the northern California coast range chaparral, we censused floral visitor communities of Trichostema laxum (Lamiaceae), quantified visiting bee behavior, and estimated outcrossing rates using a widespread Mendelian recessive floral polymorphism across a matrix of populations in burned and unburned sites. We also compared pre- and postfire floral visitation in two populations. RESULTS: Outcrossing rates were significantly lower in burned areas; however, our data suggest that the much larger size of plants in burned areas, not burn status itself, drove this pattern. Large-bodied bees dominated floral visitor communities after fire, likely recruiting to the abundant postfire floral resources. These bees visited more flowers per plant than did the smaller bees prevalent before fire and in unburned areas, likely increasing selfing through geitonogamy (within-plant pollination), an effect made possible by the far larger size of plants in burned areas. CONCLUSIONS: Outcrossing rates dropped substantially after wildfires because of changes in the pollinators, plant display size, and their interactions. Reductions in outcrossing following fire may have important implications for population resilience and evolution in a changing climate with more frequent fires.


Assuntos
Abelhas/fisiologia , Plantas/anatomia & histologia , Animais , California , Flores/anatomia & histologia , Flores/fisiologia , Fenótipo , Fenômenos Fisiológicos Vegetais , Pólen/anatomia & histologia , Pólen/fisiologia , Polinização , Reprodução , Incêndios Florestais
10.
Adv Virus Res ; 101: 149-187, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29908589

RESUMO

The capacity to spread by diverse transmission pathways enhances a virus' ability to spread effectively and survive when circumstances change. This review aims to improve understanding of how plant and insect viruses spread through natural and managed environments by drawing attention to 12 novel or neglected virus transmission pathways whose contribution is underestimated. For plant viruses, the pathways reviewed are vertical and horizontal transmission via pollen, and horizontal transmission by parasitic plants, natural root grafts, wind-mediated contact, chewing insects, and contaminated water or soil. For insect viruses, they are transmission by plants serving as passive "vectors," arthropod vectors, and contamination of pollen and nectar. Based on current understanding of the spatiotemporal dynamics of virus spread, the likely roles of each pathway in creating new primary infection foci, enlarging previously existing infection foci, and promoting generalized virus spread are estimated. All pathways except transmission via parasitic plants, root grafts, and wind-mediated contact transmission are likely to produce new primary infection foci. All 12 pathways have the capability to enlarge existing infection foci, but only to a limited extent when spread occurs via virus-contaminated soil or vertical pollen transmission. All pathways except those via parasitic plant, root graft, contaminated soil, and vertical pollen transmission likely contribute to generalized virus spread, but to different extents. For worst-case scenarios, where mixed populations of host species occur under optimal virus spread conditions, the risk that host species jumps or virus emergence events will arise is estimated to be "high" for all four insect virus pathways considered, and, "very high" or "moderate" for plant viruses transmitted by parasitic plant and root graft pathways, respectively. To establish full understanding of virus spread and thereby optimize effective virus disease management, it is important to examine all transmission pathways potentially involved, regardless of whether the virus' ecology is already presumed to be well understood or otherwise.


Assuntos
Meio Ambiente , Vírus de Insetos , Insetos/virologia , Vírus de Plantas , Plantas/virologia , Animais , Insetos Vetores/virologia , Doenças das Plantas/virologia , Plantas/anatomia & histologia , Plantas/parasitologia , Pólen/virologia
11.
PLoS One ; 12(9): e0184116, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28873457

RESUMO

Adults of many insect species often become contaminated with pollen grains when feeding. Identification of plant hosts for M. separata moths could increase our understanding of their geographic origin and the coevolution of M. separata moths and their host plants. However, identifying the diet of noctuid moths using traditional direct observation is limited by their nocturnal and flight habits. In this study, we used core barcode markers and pollen morphology to identify pollen species. We found pollen from 13 plant species belonging to nine families on trapped M. separata moths, mainly from Angiosperm, Dicotyledoneae. Pollen was found on 14.4% and 12.3% of females and males, respectively, and the amount of pollen transported varied with the body part, with the most pollen on the proboscis. We were able to determine from this that the moths visited woody plants more than herbaceous plants, but not significantly so, and that they carried more pollen earlier in the migration season. In this study, we clarified the species and frequencies of pollen deposition on M. separata moths. These findings improve our understanding of the coevolution of the moths and their host plants. Identification of plant hosts for adult moths provides a new means of studying noctuid moth-host plant interactions, and informs the development of more efficient management practices for M. separata.


Assuntos
Migração Animal/fisiologia , Interações Hospedeiro-Parasita , Mariposas/fisiologia , Plantas/parasitologia , Animais , Feminino , Masculino , Plantas/anatomia & histologia , Pólen/fisiologia , Especificidade da Espécie
12.
BMC Evol Biol ; 17(1): 149, 2017 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-28651518

RESUMO

BACKGROUND: The earliest seed plants in the Late Devonian (Famennian) are abundant and well known. However, most of them lack information regarding the frond system and reconstruction. Cosmosperma polyloba represents the first Devonian ovule in China and East Asia, and its cupules, isolated synangiate pollen organs and pinnules have been studied in the preceding years. RESULTS: New fossils of Cosmosperma were obtained from the type locality, i.e. the Leigutai Member of the Wutong Formation in Fanwan Village, Changxing County, Zhejiang Province, South China. The collection illustrates stems and fronds extensively covered in prickles, as well as fertile portions including uniovulate cupules and anisotomous branches bearing synangiate pollen organs. The stems are unbranched and bear fronds helically. Fronds are dimorphic, displaying bifurcate and trifurcate types, with the latter possibly connected to fertile rachises terminated by pollen organs. Tertiary and quaternary rachises possessing pinnules are arranged alternately (pinnately). The cupule is uniovulate and the ovule has four linear integumentary lobes fused in basal 1/3. The striations on the stems and rachises may indicate a Sparganum-type cortex. CONCLUSIONS: Cosmosperma further demonstrates diversification of frond branching patterns in the earliest seed plants. The less-fused cupule and integument of this plant are considered primitive among Devonian spermatophytes with uniovulate cupules. We tentatively reconstructed Cosmosperma with an upright, semi-self-supporting habit, and the prickles along stems and frond rachises were interpreted as characteristics facilitating supporting rather than defensive structures.


Assuntos
Evolução Biológica , Plantas/genética , Ásia Oriental , Fósseis , Óvulo Vegetal/anatomia & histologia , Óvulo Vegetal/fisiologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Fenômenos Fisiológicos Vegetais , Caules de Planta/anatomia & histologia , Plantas/anatomia & histologia , Plantas/classificação , Pólen/anatomia & histologia , Pólen/fisiologia
13.
PLoS One ; 12(6): e0179029, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28582427

RESUMO

The Talbragar Fish Bed is one of Australia's most important Jurassic deposits for freshwater fishes, land plants and aquatic and terrestrial insects. The site has yielded many well preserved fossils, which has led to the formal description of numerous new species and higher taxa. The excellent preservation of many fossils has allowed detailed anatomical studies, e.g. of the early teleost fish Cavenderichthys talbragarensis (Woodward, 1895). Here we report on the fluorescent characteristics and mineral composition of a range of Talbragar fossils. Most specimens fluoresce under ultraviolet, blue and green light. Elemental and mineralogical analyses revealed that the Talbragar fossils consist predominantly of quartz (SiO2), a mineral that is likely to account for the observed fluorescence, with trace kaolinite (Al2Si2O5(OH)4) in some of the fish fossils. Rock matrices are predominantly composed of quartz and goethite (FeO(OH)). Closer inspection of a plant leaf (Pentoxylon australicum White, 1981) establishes fluorescence as a useful tool for the visualisation of anatomical details that are difficult to see under normal light conditions.


Assuntos
Peixes/anatomia & histologia , Fósseis , Insetos/anatomia & histologia , Folhas de Planta/anatomia & histologia , Plantas/anatomia & histologia , Animais , Austrália , Evolução Biológica , História Antiga , Insetos/química , Compostos de Ferro/análise , Compostos de Ferro/química , Compostos de Ferro/história , Caulim/análise , Caulim/química , Caulim/história , Medições Luminescentes , Metais Pesados/análise , Metais Pesados/química , Metais Pesados/história , Minerais/análise , Minerais/química , Minerais/história , Folhas de Planta/química , Plantas/química , Quartzo/análise , Quartzo/química , Quartzo/história , Espectrometria de Fluorescência
14.
Plant Biol (Stuttg) ; 19(2): 115-122, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27796070

RESUMO

The characteristics of petal epidermal conical cells affect the quality of the signals perceived by various pollinators. This study aimed to identify variations in micromorphological characteristics of flower petals and their relationship to melittophily, ornithophily and chiropterophily pollination systems. The petals of 11 species were analysed using scanning electron microscopy and optical microscopy and the micromorphological traits were described, measured and compared using Tukey's test, PCA and cluster analysis. Unlike chiropterophily, all melittophilous and some ornithophilous species possessed adaxial epidermal conical cells. Cluster grouping separated chiropterophilous flowers from melittophilous and ornithophilous. PCA analysis showed that the two morphometric profile of conical cells was the attribute that most strongly influenced the grouping of species. When considering the data set of the three pollination systems, melittophilous and ornithophilous plants were more similar to each other than they were to chriopterophilous species. The distance between conical cell apices is an important parameter in interactions with pollinators. This study facilitated recognition of smoothing pollinator resource access through petal micromorphological characteristics. Further research regarding the biometry of micromorphological traits related to pollination is required.


Assuntos
Flores/anatomia & histologia , Plantas/anatomia & histologia , Polinização , Animais , Abelhas/fisiologia , Aves/fisiologia , Quirópteros/fisiologia , Flores/genética , Flores/fisiologia , Fenótipo , Epiderme Vegetal/genética , Epiderme Vegetal/fisiologia , Plantas/genética , Pólen/anatomia & histologia , Pólen/genética , Pólen/fisiologia
15.
Oecologia ; 180(4): 1037-47, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26254258

RESUMO

In Neotropical forests, lianas are increasing in abundance relative to trees. This increased species richness may reflect a positive response to global change factors including increased temperature, atmospheric CO2, habitat fragmentation, and drought severity; however, questions remain as to the specific mechanisms facilitating the response. Previous work suggests that lianas may gain an ecological advantage over trees through leaf functional traits that offer a quick return on investment of resources, although it is unknown whether this pattern extends to root traits and relationships with fungal or bacterial symbionts belowground. We sampled confamilial pairs of liana and tree species and quantified morphological and chemical traits of leaves and fine roots, as well as root symbiont abundance, to determine whether functional traits associated with resource acquisition differed between the two. Compared to trees, lianas possessed higher specific leaf area, specific root length, root branching intensity, and root nitrogen (N) and phosphorus (P) concentrations, and lower leaf and root tissue density, leaf and root carbon (C), root diameter, root C:P and N:P, and mycorrhizal colonization. Our study provides new evidence that liana leaf and root traits are characterized by a rapid resource acquisition strategy relative to trees. These liana functional traits may facilitate their response to global change, raising questions about how increased liana dominance might affect ecosystem processes of Neotropical forests.


Assuntos
Florestas , Nitrogênio/metabolismo , Fenótipo , Folhas de Planta/fisiologia , Raízes de Plantas/fisiologia , Plantas/metabolismo , Clima Tropical , Carbono/metabolismo , Meio Ambiente , Micorrizas , Fósforo/metabolismo , Folhas de Planta/anatomia & histologia , Folhas de Planta/metabolismo , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/metabolismo , Plantas/anatomia & histologia , Árvores/fisiologia
16.
Plant Biol (Stuttg) ; 18(4): 552-62, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26499392

RESUMO

Arbuscular mycorrhizal fungi (AMF) are a diverse group of soil-dwelling fungi that form symbiotic associations with land plants. AMF-plant associations promote the accumulation of plant terpenoids beneficial to human health, although how AMF mediate terpenoid accumulation is not fully understood. A critical assessment and discussion of the literature relating to mechanisms by which AMF influence plant terpenoid accumulation, and whether this symbiosis can be harnessed in horticultural ecosystems was performed. Modification of plant morphology, phosphorus availability and gene transcription involved with terpenoid biosynthetic pathways were identified as key mechanisms associated with terpenoid accumulation in AMF-colonised plants. In order to exploit AMF-plant symbioses in horticultural ecosystems it is important to consider the specificity of the AMF-plant association, the predominant factor affecting terpenoid accumulation, as well as the end use application of the harvested plant material. Future research should focus on resolving the relationship between ecologically matched AMF genotypes and terpenoid accumulation in plants to establish if these associations are effective in promoting mechanisms favourable for plant terpenoid accumulation.


Assuntos
Micorrizas/fisiologia , Plantas/microbiologia , Simbiose , Terpenos/metabolismo , Vias Biossintéticas , Ecossistema , Fósforo/metabolismo , Plantas/anatomia & histologia , Plantas/metabolismo , Terpenos/química
17.
Rev. fitoter ; 15(2): 133-146, dic. 2015. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-147882

RESUMO

El uso de productos naturales ha impactado diversos aspectos de la medicina incluyendo la salud sexual y repreductiva, con efectos deletéreos sobre los espermatozoides o afrodisiacos Se ha evaluado el efecto de diversas plantas afrodisiacas sobre los mecanismos del desempeño sexual y la calidad de los espermatozoides, lo que permite plantear que extractos de las mismas podrian facilitar la capacitación espermática. En esta revisión bibliográfica se reportan los usos farmacológicos y tradicionales de 20 plantas consideradas tradicionalmente afrodisiacas que podrian ser utilizadas como agentes naturales con efecto capacitante sobre espermatozoides humanos (AU)


O uso de produtos naturais tem tido impacto em diversos aspectos da medicina, incluindo a saude sexual e reprodutiva, tanto pelos potenciais efeitos nocivos sobre os espermatozoides como atraves do use de afrodisiacos. Estudou-se o efeito de varias plantas afrodisiacas sobre os mecanismos de desempenho sexual e qualidade das células espermaticas, para avaliar a possibilidadede melhoria da capacitagao dos espermatozoides. Neste revisao da literatura sao relatados os uses farmacologicos e tradicionais de 20 plantas tradicionalmente consideradas afrodisiacas, que poderiam ser utilizadas como compostos naturais com efeito na capacitaçao de esperma humano (AU)


The use of natural products has impacted various aspects of medicine including sexual and reproductive health, through their deleterious effect on sperm cells or as aphrodisiacs. The mechanisms of sexual performance and sperm cells quality of several aphrodisiac plants have been studied, in order of evaluating the possibility of enhancing sperm capacitation. In this literature review, the pharmacological and traditional uses of 20 aphrodisiac plants that could be used as natural agents with effect on human sperm capacitation are reported (AU)


Assuntos
Humanos , Animais , Afrodisíacos/agonistas , Afrodisíacos/síntese química , Espermatozoides/citologia , Espermatozoides/fisiologia , Saúde Sexual , Saúde Reprodutiva/educação , Saúde Reprodutiva/etnologia , Plantas/anatomia & histologia , Gravidez/genética , Terapêutica/métodos , Afrodisíacos/administração & dosagem , Afrodisíacos/efeitos adversos , Espermatozoides/anormalidades , Espermatozoides/classificação , Saúde Reprodutiva/classificação , Saúde Reprodutiva/tendências , Plantas/efeitos adversos , Gravidez/metabolismo , Terapêutica/normas
18.
Ann Bot ; 116(6): 987-99, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26113632

RESUMO

BACKGROUND: Increasing attention is being focused on the influence of rapid increases in atmospheric CO2 concentration on nutrient cycling in ecosystems. An understanding of how elevated CO2 affects plant utilization and acquisition of phosphorus (P) will be critical for P management to maintain ecosystem sustainability in P-deficient regions. SCOPE: This review focuses on the impact of elevated CO2 on plant P demand, utilization in plants and P acquisition from soil. Several knowledge gaps on elevated CO2-P associations are highlighted. CONCLUSIONS: Significant increases in P demand by plants are likely to happen under elevated CO2 due to the stimulation of photosynthesis, and subsequent growth responses. Elevated CO2 alters P acquisition through changes in root morphology and increases in rooting depth. Moreover, the quantity and composition of root exudates are likely to change under elevated CO2, due to the changes in carbon fluxes along the glycolytic pathway and the tricarboxylic acid cycle. As a consequence, these root exudates may lead to P mobilization by the chelation of P from sparingly soluble P complexes, by the alteration of the biochemical environment and by changes to microbial activity in the rhizosphere. Future research on chemical, molecular, microbiological and physiological aspects is needed to improve understanding of how elevated CO2 might affect the use and acquisition of P by plants.


Assuntos
Dióxido de Carbono/farmacologia , Fósforo/metabolismo , Plantas/efeitos dos fármacos , Ecossistema , Fotossíntese , Exsudatos de Plantas , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Plantas/anatomia & histologia , Plantas/metabolismo , Solo/química , Microbiologia do Solo
19.
Naturwissenschaften ; 101(11): 893-905, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25204723

RESUMO

Long-tubed hawkmoth-pollinated species present some of the most remarkable examples of floral specialization depending exclusively on long-tongued hawkmoths for sexual reproduction. Nonetheless, long-tongued hawkmoths do not rely exclusively on specialized plants as nectar sources, which may limit sexual reproduction through pollen limitation. However, very few studies have quantified the level of pollen limitation in plants with highly specialized floral traits in tropical regions. In this context, we studied four sympatric hawkmoth-pollinated species in a highland Atlantic Rain forest and assessed pollen limitation and their dependence on pollinators by analyzing the floral biology, breeding system, pollination mechanisms, and abundance of long-tongued pollinators. We showed that the four species are self-compatible, but are completely dependent on long-tongued hawkmoths to set fruits, and that flower visitation was infrequent in all plant species. Pollen limitation indices ranged from 0.53 to 0.96 showing that fruit set is highly limited by pollen receipt. Long-tongued moths are much less abundant and comprise only one sixth of the hawkmoth fauna. Pollen analyses of 578 sampled moths revealed that hawkmoths visited ca. 80 plant species in the community, but only two of the four species studied. Visited plants included a long-tubed hawkmoth-pollinated species endemic to the lowland forest ca. 15-20 km away from the study site. Specialization index (H 2 ' = 0.20) showed that community-level interactions between hawkmoths and plants are generalized. We suggest that sexual reproduction of these highly specialized hawkmoth-pollinated species is impaired by competition among plants for pollinators, in conjunction with the low abundance and diversity of long-tongued pollinators.


Assuntos
Florestas , Mariposas/fisiologia , Fenômenos Fisiológicos Vegetais , Polinização , Animais , Brasil , Flores/anatomia & histologia , Plantas/anatomia & histologia , Pólen/fisiologia , Densidade Demográfica
20.
Methods Mol Biol ; 1080: 147-57, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24132426

RESUMO

Use of electron tomography methods improves image resolution of transmission electron microscopy especially in the z-direction, enabling determination of complicated 3D structures of organelles and cytoskeleton arrays. The increase in resolution necessitates preservation of cellular structures close to the native states with minimum artifacts. High-pressure freezing (HPF) that immobilizes molecules in the cell instantaneously has been used to avoid damages caused by convention chemical fixation. Despite the advantages of HPF, cells could still be damaged during dissection prior to HPF. Therefore, it is critical to isolate cells/tissues of interest quickly and carefully. The samples frozen by HPF are often processed by freeze substitution (FS), and FS should be carried out under appropriate conditions. Here we describe dissection, HPF, and FS methods that we have utilized to prepare plant samples for electron tomography/immuno-electron microscopy.


Assuntos
Criopreservação/métodos , Plantas/anatomia & histologia , Plantas/ultraestrutura , Cebolas/anatomia & histologia , Cebolas/crescimento & desenvolvimento , Plântula/anatomia & histologia , Plântula/crescimento & desenvolvimento
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