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1.
Ecotoxicol Environ Saf ; 181: 419-427, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31220782

RESUMO

Nonylphenol (NP) and its detrimental effects on the environment, humans, wildlife, fish and birds is an increasingly important global research focus. The number of investigations on the toxicity and metabolic fate of NP in plants is however limited. This paper reviews the prevalence and source of NP in plants and the effect it has on its morphological, physiological and ultrastructural status. Fruit and vegetables have been found to contain levels of NP that is twenty-fold exceeding the no observable effect level (NOEL) of freshwater algae. Apart from the potential risk this poses to the health of consumers, it can overburden the plant's natural defence system, leading to growth disorders. Plants exposed to NP show signs of overall growth reduction, changes in organelle structure and oxidative damage. These adverse effects may exacerbate the food security dilemma faced by many countries and impede their progress towards attaining the sustainable development goals.


Assuntos
Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Fenóis/toxicidade , Plantas/efeitos dos fármacos , Animais , Disruptores Endócrinos/análise , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Frutas/química , Frutas/crescimento & desenvolvimento , Humanos , Fenóis/análise , Desenvolvimento Vegetal/efeitos dos fármacos , Plantas/anatomia & histologia , Plantas/metabolismo , Verduras/química , Verduras/crescimento & desenvolvimento
2.
Methods Mol Biol ; 1992: 109-119, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31148034

RESUMO

This chapter gives examples of basic procedures of quantification of plant structures with use of image analysis, which are commonly employed to describe differences among experimental treatments or phenotypes of plant material. Tasks are demonstrated with the use of ImageJ, a widely used public domain Java image processing program. Principles of sampling design based on systematic uniform random sampling for quantitative studies of anatomical parameters are given to obtain their unbiased estimations and simplified "rules of thumb" are presented. The basic procedures mentioned in the text are: (1) sampling, (2) calibration, (3) manual length measurement, (4) leaf surface area measurement, (5) estimation of particle density demonstrated on an example of stomatal density, and (6) analysis of epidermal cell shape.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Epiderme Vegetal/anatomia & histologia , Folhas de Planta/anatomia & histologia , Plantas/anatomia & histologia , Microscopia/métodos , Imagem Óptica/métodos , Epiderme Vegetal/ultraestrutura , Folhas de Planta/ultraestrutura , Estômatos de Plantas/anatomia & histologia , Estômatos de Plantas/ultraestrutura , Plantas/ultraestrutura , Software
3.
Nat Commun ; 10(1): 2203, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101818

RESUMO

The root economics spectrum (RES), a common hypothesis postulating a tradeoff between resource acquisition and conservation traits, is being challenged by conflicting relationships between root diameter, tissue density (RTD) and root nitrogen concentration (RN). Here, we analyze a global trait dataset of absorptive roots for over 800 plant species. For woody species (but not for non-woody species), we find nonlinear relationships between root diameter and RTD and RN, which stem from the allometric relationship between stele and cortical tissues. These nonlinear relationships explain how sampling bias from different ends of the nonlinear curves can result in conflicting trait relationships. Further, the shape of the relationships varies depending on evolutionary context and mycorrhizal affiliation. Importantly, the observed nonlinear trait relationships do not support the RES predictions. Allometry-based nonlinearity of root trait relationships improves our understanding of the ecology, physiology and evolution of absorptive roots.


Assuntos
Evolução Biológica , Raízes de Plantas/genética , Plantas/genética , Característica Quantitativa Herdável , Conjuntos de Dados como Assunto , Dinâmica não Linear , Fenótipo , Filogenia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/metabolismo , Plantas/anatomia & histologia , Plantas/metabolismo
4.
Int J Mol Sci ; 20(9)2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31075826

RESUMO

The INDETERMINATE DOMAIN (IDD) genes comprise a conserved transcription factor family that regulates a variety of developmental and physiological processes in plants. Many recent studies have focused on the genetic characterization of IDD family members and revealed various biological functions, including modulation of sugar metabolism and floral transition, cold stress response, seed development, plant architecture, regulation of hormone signaling, and ammonium metabolism. In this review, we summarize the functions and working mechanisms of the IDD gene family in the regulatory network of metabolism and developmental processes.


Assuntos
Genes de Plantas , Plantas/genética , Sequência de Aminoácidos , Gravitropismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas/anatomia & histologia
5.
Sci Total Environ ; 672: 583-592, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30965269

RESUMO

Vascular plants have been found to align along globally-recognised resource-allocation trade-offs among specific functional traits. Genetic constrains and environmental pressures limit the spectrum of viable resource-use strategies employed by plant species. While conspecific plants have often been described as identical, intraspecific variation facilitates species coexistence and evolutionary potential. This study attempts to link an individual's phenotype to its environmental tolerance and ecosystem function. We hypothesised that: (1) seasonal variation in water availability has selected for tight phenotypic integration patterns that shape Mediterranean vegetation; however, (2) coexisting species employ alternative resource-use strategies to avoid competitive exclusion; specifically (3) species with smaller climatic niches (i.e. potential distributions) display higher functional diversity. We examined the interdependence among and the sources of variation within 11 functional traits, reflecting whole-plant economics (e.g. construction costs, hydraulics, defences, water storage capacity), from nine dominant, thermo-Mediterranean species measured across a wide environmental and geographic gradient. Furthermore, we delineated the phenotypic and climatic hypervolumes of each studied species to test for climatic niche overlap and functional distinctiveness. By adopting this multidimensional trait-based approach we detected fundamental phenotypic integration patterns that define thermo-Mediterranean species regardless of life history strategy. The studied traits emerged intercorrelated shaping a resource-allocation spectrum. Significant intraspecific variability in most measured traits allowed for functional distinctiveness among the measured species. Higher functional diversity was observed in species restricted within narrower climatic niches. Our results support our initial hypotheses. The studied functional traits collectively formed an integrated space of viable phenotypic expressions; however, phenotypic plasticity enables functionally distinctive species to succeed complementary in a given set of environmental conditions. Functional variability among coexisting individuals defined species' climatic niches within the trait-spectrum permitted by Mediterranean conditions. Ultimately, a species establishment in a locality depends on the extent that it can shift its trait values.


Assuntos
Ecossistema , Monitoramento Ambiental , Fenótipo , Plantas/classificação , Biodiversidade , Clima , Região do Mediterrâneo , Nitrogênio , Folhas de Planta , Plantas/anatomia & histologia , Estações do Ano , Solo , Especificidade da Espécie
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.
PLoS One ; 14(3): e0213029, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30865672

RESUMO

The obligate mutualism and exquisite specificity of many plant-pollinator interactions lead to the expectation that flower phenotypes (e.g., corolla tube length) and corresponding pollinator traits (e.g., hawkmoth proboscis length) are congruent as a result of coevolution by natural selection. However, the effect of variation in flower morphology on the fitness of plants and their pollinators has not been quantified systematically. In this study, we employed the theoretical morphospace paradigm using a combination of 3D printing, electronic sensing, and machine vision technologies to determine the influence of two flower morphological features (corolla curvature and nectary diameter) on the fitness of both parties: the artificial flower and its hawkmoth pollinator. Contrary to the expectation that the same flower morphology maximizes the fitness of both plant and pollinator, we found that the two parties have divergent optima for corolla curvature, with non-overlapping fitness peaks in flower morphospace. The divergent fitness optima between plants and pollinators could lead to evolutionary diversification in both groups.


Assuntos
Biodiversidade , Mariposas/fisiologia , Plantas/anatomia & histologia , Polinização , Simbiose/fisiologia , Animais , Coevolução Biológica , Comportamento Alimentar , Feminino , Flores/anatomia & histologia , Masculino , Mariposas/anatomia & histologia , Fenótipo
8.
New Phytol ; 223(3): 1159-1165, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30897214

RESUMO

Allometry determines how tree shape and function scale with each other, related through size. Allometric relationships help scale processes from the individual to the global scale and constitute a core component of vegetation models. Allometric relationships have been expected to emerge from optimisation theory, yet this does not suitably predict empirical data. Here we argue that the fusion of high-resolution data, such as those derived from airborne laser scanning, with individual-based forest modelling offers insight into how plant size contributes to large-scale biogeochemical processes. We review the challenges in allometric scaling, how they can be tackled by advances in data-model fusion, and how individual-based models can serve as data integrators for dynamic global vegetation models.


Assuntos
Florestas , Modelos Biológicos , Plantas/anatomia & histologia , Tecnologia de Sensoriamento Remoto , Teorema de Bayes , Árvores/anatomia & histologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-30708968

RESUMO

The potential of urban greening plants to capture particulate matter (PM) from the ambient atmosphere is contingent on interactions between the level of pollution and leaf surfaces. For this study, thirteen plant species were investigated to quantify their capacity of PM accumulation under three atmospheric environments, that is, industrial, traffic and university campus (control), in Kunming City (Southwest China). The sampled sites represented different pollution levels (that is, high pollution, slight pollution and clean air, respectively). The plant species differed in their accumulation of PM by six- to eight-fold across the three sites. Magnolia grandiflora was the most efficient evergreen tree species, whereas Platanus acerifolia had the highest capture of PM among deciduous trees. The accumulation capacity of the same species varied with the degree of pollution. For example, Osmanthus fragrans, Loropetalum chinense and Cinnamomum japonicum were highly efficient for the capture of PM in the traffic and university campus areas; however, they exhibited medium accumulation in the industrial area. Prunus majestica demonstrated an intermediate accumulation capacity in the industrial area, but was low in the traffic and university campus areas. The capturing capacity of the same genus was also different among the different levels of pollution. For example, C. japonicum had a 2.9⁻4.2-times higher PM accumulation than did C. camphora across the three sites. There were significant differences in leaf surface area, stomata density/length, guard cell area, and trichome density/length among these species. The species-specific efficacy of PM capture was primarily contributed to by leaf size and surface roughness, stomata density, and trichome length. In particular, hairy-leaf leaves with medium stomatal density exhibited higher PM capture. Therefore, leaf micromorphology, leaf size and longevity appeared to be significant predictive factors for the accumulation of PM, which may aid in the selection of greening plant species for the remediation of pollutants in urban areas.


Assuntos
Poluentes Atmosféricos/metabolismo , Recuperação e Remediação Ambiental/estatística & dados numéricos , Material Particulado/metabolismo , Folhas de Planta/metabolismo , Plantas/metabolismo , China , Cidades , Recuperação e Remediação Ambiental/métodos , Folhas de Planta/anatomia & histologia , Plantas/anatomia & histologia , Plantas/classificação , Especificidade da Espécie
10.
New Phytol ; 222(3): 1235-1241, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30632169

RESUMO

Contents Summary 1235 I. Introduction 1235 II. The many shapes of phenotypic plasticity 1236 III. Random regression mixed model framework 1237 IV. Conclusions 1240 Acknowledgements 1240 References 1240 SUMMARY: Plant biology is experiencing a renewed interest in the mechanistic underpinnings and evolution of phenotypic plasticity that calls for a re-evaluation of how we analyse phenotypic responses to a rapidly changing climate. We suggest that dissecting plant plasticity in response to increasing temperature needs an approach that can represent plasticity over multiple environments, and considers both population-level responses and the variation between genotypes in their response. Here, we outline how a random regression mixed model framework can be applied to plastic traits that show linear or nonlinear responses to temperature. Random regressions provide a powerful and efficient means of characterising plasticity and its variation. Although they have been used widely in other fields, they have only recently been implemented in plant evolutionary ecology. We outline their structure and provide an example tutorial of their implementation.


Assuntos
Adaptação Fisiológica , Mudança Climática , Plantas/anatomia & histologia , Modelos Biológicos , Análise de Regressão , Temperatura Ambiente
11.
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
12.
Curr Opin Biotechnol ; 56: 202-208, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30677701

RESUMO

Lignin, a polymer found in the plant secondary cell wall, is a major contributor to biomass' recalcitrance toward saccharification. Because of this negative impact toward the value of lignocellulosic crops, there is a special interest in modifying the content and composition of this important plant biopolymer. For many years this endeavor has been hindered by the plant growth inhibition that is often associated with manipulations to phenylpropanoid metabolism. Although the actual mechanism by which dwarfism arises remains unknown, recent advances in tissue-specific lignin complementation and better understanding of phenylpropanoid transcriptional regulation has made it possible to disentangle lignin modification from perturbations in plant development.


Assuntos
Lignina/metabolismo , Desenvolvimento Vegetal , Propanóis/metabolismo , Parede Celular/metabolismo , Feixe Vascular de Plantas/fisiologia , Plantas/anatomia & histologia , Plantas/metabolismo
13.
New Phytol ; 222(3): 1338-1351, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30664250

RESUMO

Evolutionary history shapes the interspecific relatedness and intraspecific variation, which has a profound influence on plant functional traits and productivity. However, it is far from clear how the phylogenetic relatedness among species and intraspecific variation could contribute to the observed variance in plant biomass responses to climate warming. We compiled a dataset with 284 species from warming experiments to explore the relative importance of phylogenetic, intraspecific, experimental and ecological factors to warming effects on plant biomass, using phylogenetic eigenvector regression and variance decomposition. Our results showed that phylogenetic relatedness could account for about half the total variance in biomass responses to warming, which were correlated with leaf economic traits at the family level but not at species level. The intraspecific variation contributed to approximately one-third of the variance, whereas the experimental design and ecological characteristics only explained 7-17%. These results suggest that intrinsic factors (evolutionary history) play more important roles than extrinsic factors (experimental treatment and environment) in determining the responses of plant biomass to warming at the global scale. This highlights the urgent need for land surface models to include evolutionary aspects in predicting ecosystem functions under climate change.


Assuntos
Evolução Biológica , Biomassa , Aquecimento Global , Plantas/anatomia & histologia , Filogenia , Folhas de Planta/fisiologia , Característica Quantitativa Herdável , Especificidade da Espécie
16.
Curr Opin Plant Biol ; 47: 56-63, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30308452

RESUMO

The growth of individual cells underlies the development of biological forms. In plants, cells are interconnected by rigid walls, fixing their position with respect to one another and generating mechanical feedbacks between cells. Current research is shedding new light on how plant growth is controlled by physical inputs at the level of individual cells and growing tissues. In this review, we discuss recent progress in our understanding of the cellular basis of growth from a biomechanical perspective. We describe the role of the cell wall and turgor pressure in growth and highlight the often-overlooked role of cell geometry in this process. It is becoming apparent that a combination of experimental and theoretical approaches is required to answer new emerging questions in the biomechanics of plant morphogenesis. We summarise how this multidisciplinary approach brings us closer to a unified understanding of the generation of biological forms in plants.


Assuntos
Células Vegetais/metabolismo , Desenvolvimento Vegetal , Plantas/anatomia & histologia , Forma Celular , Modelos Biológicos , Especificidade de Órgãos
17.
Sci Total Environ ; 657: 597-607, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30550922

RESUMO

In mountainous torrents of the Mediterranean environment the riparian vegetation is strongly influenced by the presence of engineering control works, since these structures bring heavy modifications in channel geometry, hydraulic regime and bed sediment size. Previous investigations have shown high linear correlations between physical (section shape, profile slope, specific discharge, surface and subsurface size of the channel bed) and vegetation (development, structure and biodiversity) indicators in headwater channels with check dams of Calabrian (Southern Italy) torrents. Based on these findings, this study applies multivariate statistical techniques (Principal Component Analysis and Partial Least Square Regression) to identify in the same study headwaters new synthetic explanatory variables, representative of the different transects (upstream, downstream or intermediate, compared to the check dam location) and develop predictive models of riparian vegetation characteristics. The Principal Component Analysis has provided a simple parameter (the first Principal Component, explaining about 60% of the total variance), which is able to discriminate the physical and vegetal characteristics of the different transects close to check dams, thus reducing the large number of factors influencing the fluvial processes. Moreover, cover, height and transversal variability of riparian vegetation have a very high influence (loadings over 0.73) on this component, while its biodiversity is correlated to the second Principal Component (loadings over 0.63). The Partial Least Square Regression has shown that it is possible to estimate with fair accuracy (minimum r2 of 0.70) the development, structure as well as transversal variability of the riparian vegetation, starting from the physical features of the channel. These models may be important in the planning steps of new check dams, since their effects on the development and growth of vegetation upstream and downstream can be forecasted before their installation, at least for the quantification of the order of magnitude of the check dam impacts on torrent ecology.


Assuntos
Biodiversidade , Sedimentos Geológicos/análise , Desenvolvimento Vegetal , Plantas/anatomia & histologia , Movimentos da Água , Abastecimento de Água , Água Doce , Itália , Análise dos Mínimos Quadrados , Modelos Biológicos , Análise Multivariada , Análise de Componente Principal , Abastecimento de Água/métodos
18.
New Phytol ; 222(4): 1742-1750, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30415486

RESUMO

Contents Summary I. Introduction II. Evolving modes of phenological study III. The phenocam approach IV. Applications of the phenocam method V. Looking forward Acknowledgements References SUMMARY: Global change is shifting the seasonality of vegetation in ecosystems around the globe. High-frequency digital camera imagery, and vegetation indices derived from that imagery, is facilitating better tracking of phenological responses to environmental variation. This method, commonly referred to as the 'phenocam' approach, is well suited to several specific applications, including: close-up observation of individual organisms; long-term canopy-level monitoring at individual sites; automated phenological monitoring in regional-to-continental scale observatory networks; and tracking responses to experimental treatments. Several camera networks are already well established, and some camera records are a more than a decade long. These data can be used to identify the environmental controls on phenology in different ecosystems, which will contribute to the development of improved prognostic phenology models.


Assuntos
Ecossistema , Imagem Tridimensional , Fotografação/instrumentação , Plantas/anatomia & histologia , Estações do Ano , Geografia
19.
New Phytol ; 222(2): 670-686, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30394553

RESUMO

Contents Summary 670 I. Introduction 671 II. Principle 1 - Plant respiration performs three distinct functions 673 III. Principle 2 - Metabolic pathway flexibility underlies plant respiratory performance 676 IV. Principle 3 - Supply and demand interact over time to set plant respiration rate 677 V. Principle 4 - Plant respiratory acclimation involves adjustments in enzyme capacities 679 VI. Principle 5 - Respiration is a complex trait that helps to define, and is impacted by, plant lifestyle strategies 680 VII. Future directions 680 Acknowledgements 682 References 682 SUMMARY: Respiration is a core biological process that has important implications for the biochemistry, physiology, and ecology of plants. The study of plant respiration is thus conducted from several different perspectives by a range of scientific disciplines with dissimilar objectives, such as metabolic engineering, crop breeding, and climate-change modelling. One aspect in common among the different objectives is a need to understand and quantify the variation in respiration across scales of biological organization. The central tenet of this review is that different perspectives on respiration can complement each other when connected. To better accommodate interdisciplinary thinking, we identify distinct mechanisms which encompass the variation in respiratory rates and functions across biological scales. The relevance of these mechanisms towards variation in plant respiration are explained in the context of five core principles: (1) respiration performs three distinct functions; (2) metabolic pathway flexibility underlies respiratory performance; (3) supply and demand interact over time to set respiration rates; (4) acclimation involves adjustments in enzyme capacities; and (5) respiration is a complex trait that helps to define, and is impacted by, plant lifestyle strategies. We argue that each perspective on respiration rests on these principles to varying degrees and that broader appreciation of how respiratory variation occurs can unite research across scales.


Assuntos
Plantas/metabolismo , Trifosfato de Adenosina/metabolismo , Respiração Celular , Redes e Vias Metabólicas , Mitocôndrias/metabolismo , Oxirredução , Plantas/anatomia & histologia
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