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Allelochemicals from Alexandrium minutum induce rapid inhibition of metabolism and modify the membranes from Chaetoceros muelleri ArchiMer
Long, Marc; Tallec, Kevin; Soudant, Philippe; Le Grand, Fabienne; Donval, Anne; Lambert, Christophe; Sarthou, Geraldine; Jolley, Dianne F.; Hegaret, Helene.
Allelochemical interactions are likely to be a contributing factor explaining the success of large blooms of the harmful marine dinoflagellate Alexandrium, however, the physiological mechanisms of allelochemical interactions remain poorly described. Here we investigated the sub-lethal effects (on an hourly scale) of a filtrate containing allelochemicals from Alexandrium minutum on the physiology of the common diatom Chaetoceros muelleri. The filtrate induced deleterious effects to the diatom physiology within only 30 min of exposure. Esterase activity and photosynthesis were drastically inhibited, with up to 34% of the population being metabolically inactive and up to 30% reduction in photosystem II quantum yield when exposed to the filtrate. In addition,...
Tipo: Text Palavras-chave: Allelopathy; Alexandrium; Metabolism; Photoinhibition; Lipids; Pigments.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00460/57133/59748.pdf
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Características fotossintéticas de genótipos de capim-elefante anão (Pennisetum purpureum Schum.), em estresse hídrico - DOI: 10.4025/actascianimsci.v32i1.8961 Animal Sciences
Araújo, Saulo Alberto do Carmo; UFVJM; Vasquez, Hernan Maldonado; UENF; Campostrini, Eliemar; UENF; Netto, Alena Torres; UENF; Deminicis, Bruno Borges; UENF; Lima, Érico da Silva; UENF.
O experimento foi realizado com o objetivo de avaliar as trocas gasosas de genótipos de capim-elefante anão, em diferentes condições hídricas. O delineamento experimental foi inteiramente casualizado com três repetições. Foram avaliados três genótipos de capim-elefante anão (Mott, CNPGL 94-34-3 e CNPGL 92-198-7) em duas condições de umidade do solo: irrigado (I) e não-irrigado (NI). Foi observada diferença entre os tratamentos I e NI para todos os genótipos em relação à taxa fotossintética, condutância estomática, transpiração e déficit de pressão de vapor. O genótipo CNPGL 94-34-3 apresentou maior tolerância ao estresse hídrico, seguido pelos genótipos Mott e CNPGL 92-198-7. Todos os genótipos avaliados apresentaram, em condições ideais de umidade do...
Tipo: Pesquisa de campo Palavras-chave: Ciências Agrárias condutância estomática; Déficit de pressão de vapor; Fotoinibição; Fotossíntese; Transpiração Zootecnia stomatal conductance; Vapor pressure deficit; Photoinhibition; Photosynthesis; Transpiration.
Ano: 2009 URL: http://periodicos.uem.br/ojs/index.php/ActaSciAnimSci/article/view/8961
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Chlorophyll fluorescence varies more across seasons than leaf water potential in drought-prone plants Anais da ABC (AABC)
ROSADO,BRUNO H.P.; MATTOS,EDUARDO A. DE.
ABSTRACT Among the effects of environmental change, the intensification of drought events is noteworthy, and tropical vegetation is predicted to be highly vulnerable to it. However, it is not clear how tropical plants in drought-prone habitats will respond to this change. In a coastal sandy plain environment, we evaluated the response of six plant species to water deficits across seasons, the relationship between their morpho-physiological traits, and which traits would be the best descriptors of plants' response to drought. Regardless of leaf succulence and phenology, responses between seasons were most strongly related to chlorophyll fluorescence. In this study we have demonstrated that a better comprehension of how tropical species from drought-prone...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Drought; Functional traits; Plant-water relations; Photoinhibition; Seasonal habitats.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652016000200549
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Ecophysiology of tea Braz. J. Plant Physiol.
De Costa,W.A. Janendra M.; Mohotti,A. Janaki; Wijeratne,Madawala A..
Tea [Camellia sinensis (L.) O. Kuntze] is one of the most important beverage crops in the world. The major tea-growing regions of the world are South-East Asia and Eastern Africa where it is grown across a wide range of altitudes up to 2200 m a.s.l.. This paper reviews the key physiological processes responsible for yield determination of tea and discusses how these processes are influenced by genotypic and environmental factors. Yield formation of tea is discussed in terms of assimilate supply through photosynthesis and formation of harvestable sinks (i.e. shoots). The photosynthetic apparatus and partial processes (i.e. light capture, electron transport and carboxylation) of tea show specific adaptations to shade. Consequently, maximum light-saturated...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Climate change; Photoinhibition; Photosynthesis; Shoot growth; Temperature; Vapour pressure deficit; Water potential.
Ano: 2007 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000400005
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Effects of light stress on the growth of the epiphytic orchid Cattleya forbesii Lindl. X Laelia tenebrosa Rolfe Rev. Bras. Bot.
STANCATO,GIULIO C.; MAZZAFERA,PAULO; BUCKERIDGE,MARCOS S..
Considering the performance of CAM epiphytes under high levels of radiation or in shaded environments, with growth rate proportional to light intensity, the objective of this work was to evaluate the effects of long-term light stress on the growth of a Brazilian epiphytic orchid, Cattleya forbesii Lindl. X Laelia tenebrosa Rolfe. Two groups of plants were used in the first experiment, one under 90% (<FONT FACE=Symbol>@</FONT> 1,650 µmol.m-2.s-1) of Photosynthetically Active Radiation (PAR) and the other maintained under 22.5% (<FONT FACE=Symbol>@</FONT> 400 µmol.m-2.s-1). In the second experiment the diffusive resistance, transpiration rate and fluorescence levels were monitored for plants that were under 22.5% of PAR, under 90% and...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Photoinhibition; Storage; Orchids; Pseudobulb.
Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042002000200011
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Expression of Early Light Induced Protein in Grapevine and Pea, under Different Conditions and its Relation with Photoinhibition Chilean J. Agric. Res.
Berti,Maritza; Pinto,Manuel.
Early light induced proteins (ELIP) are a type of proteins which are expressed before than other chloroplast proteins in the presence of light. These proteins have been studied in a large number of annual species such as pea (Pisum sativum L.), barley (Hordeum vulgare L.) and Arabidopsis sp. In perennials plants the studies about ELIPs are very scarce. The possible photoprotective function of the ELIPs has motivated the interest in investigating the presence of this type of proteins in a perennial plant such as grapevine (Vitis vinifera L.) and if their characteristics differ from those found in annual plants. In this paper a comparative study was conducted on the ELIPs expression in grapevine and pea to investigate whether there are differences regarding...
Tipo: Journal article Palavras-chave: Photoinhibition; ELIPs induction; Abiotic stress; Vitis vinifera; Pisum sativum.
Ano: 2012 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000300011
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Expression of LHC Genes and their Relation to Photo-Oxidative Stress Tolerance Tolerance in Solanum lycopersicum L. and Solanum chilense (Dunal) Reiche Chilean J. Agric. Res.
Chilian,Javier; Verdugo,Isabel; Poblete,Fernando; Ruiz-Lara,Simón; Casaretto,José A; González,Enrique.
Simultaneous exposition to low temperature and high light radiation cause photoinhibition of photosynthetic apparatus, affecting the productivity and geographical distribution of agricultural crops. In several Solanaceous species, tolerance to low temperature stress in combination with high light has been associated with some stimulation in non-photochemical quenching (NPQ), which involved reorganization in light-harvesting complex (LHC) proteins. To study photosynthetic performance in Solanum lycopersicum L. and S. chilense (Dunal) Reiche, and to investigate transcriptional regulation of genes encoding LHC proteins and their involvement in the NPQ, plants of both species were exposed to low temperature (4 °C) and high light radiation (1300 /<mol m-2...
Tipo: Journal article Palavras-chave: Lipid-peroxidation; Photoinhibition; Photochemical quenching; Zeaxanthin.
Ano: 2011 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000400002
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Fotoinibição em três espécies do cerrado (Annona crassifolia, Eugenia dysenterica e Campomanesia adamantium ) na estação seca e na chuvosa Rev. Bras. Bot.
LEMOS FILHO,JOSÉ PIRES DE.
O objetivo deste estudo foi verificar a performance fotossintética e a ocorrência de fotoinibição em três espécies do cerrado, na estação seca e estação chuvosa. Os valores do rendimento quântico potencial do fotossistema II (Fv/Fm) após 1 hora de adaptação ao escuro, ao meio dia, foram inferiores a 0,8 para todas as espécies nas duas estações, caracterizando a presença da fotoinibição. Na estação seca, apesar das reduções observadas na condutância estomática, no rendimento quântico efetivo(DF/F`m) e na taxa aparente de transporte de elétrons (ETR), a saturação da fotossíntese foi similar à observada na estação chuvosa, para todas as espécies estudadas, aproximadamente 1500 mmol.m-2.s-1. Nesse nível de luz, o excesso relativo do fluxo de fótons de...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Photosynthesis; Photoinhibition; "cerrado" plants.
Ano: 2000 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042000000100005
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Maximizing microalgae productivity in a light-limited chemostat ArchiMer
Martinez, Carlos; Bernard, Olivier; Mairet, Francis.
Light supply is one of the most important parameters to be considered for enhancing microalgae growth in photobioreactors (PBR) with artificial light. However, most of the mathematical works do not consider incident light as a parameter to be optimized. In this work based on a simple model of light-limited growth, we determine optimal values for the dilution rate and the incident light intensity in order to maximize the steady-state microalgal surface productivity in a continuous culture. We also show that in optimal conditions there is a minimal initial microalgal concentration (and we give a simple expression to determine it) to guarantee the persistence of the population. Finally, in the context of enhancing microalgae productivity by reducing light...
Tipo: Text Palavras-chave: Dynamics and control; Industrial biotechnology; Photoinhibition; Biomass productivity; Microalgae; Photoacclimation; Chlorophyll.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00439/55091/56653.pdf
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Morphological and physiological adjustments of Brazilwood (Caesalpinia echinata Lam.) to direct solar radiation Braz. J. Plant Physiol.
Mengarda,Liana Hilda Golin; Milanez,Camilla Rozindo Dias; Silva,Diolina Moura; Aguilar,Marco Antonio Galeas; Cuzzuol,Geraldo Rogério Faustini.
This study aimed to characterize the alarm and resistance phases of stress of Caesalpinia echinata under intense irradiance in order to better define its position on forest succession. The alarm phase was identified by rapid reduction in the maximum quantum yield of PSII primary photochemical reactions (ΦP0 = FV/FM) and Performance Index (PIABS) followed by total leaf abscission in the first week of exposure to direct sunlight. The new leaves grown showed recovery of chlorophyll a parameters, increase in blade thickness, elongation of the palisade and spongy parenchymas, higher water content, and reduction of specific leaf area. These changes were associated with the osmoprotector of sucrose and antioxidative of raffinose effects, which indicate an...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Forest succession; Light stress; Photoinhibition; Leaf anatomy; Soluble carbohydrates.
Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202012000300003
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Photosynthesis and carbon gain under contrasting light levels in seedlings of a pioneer and a climax tree from a Brazilian Semideciduous Tropical Forest Rev. Bras. Bot.
Silvestrini,Milene; Válio,Ivany Ferraz Marques; Mattos,Eduardo Arcoverde de.
In this study we evaluated photosynthetic characteristics and patterns of biomass accumulation in seedlings of two tree species from a Semideciduous Tropical Forest of Brazil. Seedlings of Trema micrantha (L.) Blum. (pioneer) and Hymenaea courbaril (L.) var. stilbocarpa (Hayne) Lee &amp; Langenh. (climax) were grown for 4 months under low light (LL) (5%-8% of sunlight) and high light (HL) (100% of sunlight). Under HL, T. micrantha showed higher CO2 assimilation rates (A CO2) and light saturation than H. courbaril. Under LL, A CO2 were higher in H. courbaril. Under LL, total chlorophyll and carotenoid contents per unit leaf area were higher in H. courbaril. Chlorophyll a/b ratio was higher in T. micrantha under both light regimes. A CO2 and Fv/Fm ratio...
Tipo: Info:eu-repo/semantics/article Palavras-chave: CO2 assimilation; Growth response to light; Hymenaea courbaril; Photoinhibition; Trema micrantha.
Ano: 2007 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042007000300011
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Photosynthetic analyses of two native Atlantic Forest species in regenerative understory of eucalyptus plantation Braz. J. Plant Physiol.
Lage-Pinto,Frederico; Bernini,Elaine; Oliveira,Jurandi Gonçalves de; Vitória,Angela Pierre.
Gas exchange, chlorophyll afluorescence, and photosynthetic pigments of Xylopia sericeaA. St.-Hil. and Siparuna guianensis Aubl. were evaluated during the rainy season and the dry season (2009-2010) in three understories with different ecological conditions (irradiance, water availability, and temperature) located in the União Biological Reserve (known as REBIO União), at Rio de Janeiro State, a natural forest understory, eucalyptus understory under regeneration, and understory of eucalyptus plantation with 18-year-old trees that were removed 1 year before. The lowest values of Fv/Fm e Fm/Fo were observed in the exposed understory for both seasons, with lower values in the dry season, suggesting that reduced water availability potentializes the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Corymbia citriodora; Dehydration; Photoinhibition; Siparuna guianensis; Xylopia sericea.
Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202012000200003
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Photosynthetic Potential and Productivity of Common Beans under Herbicide Effect Planta Daninha
LIMA,G.R.; MACEDO,D.C.; BARROS,R.L.N.; MACHADO,A.F.L.; PIMENTEL,C..
ABSTRACT: The objective of this study was to evaluate the effects of the application of contact herbicides recommended for common bean crops, as for chlorophyll a fluorescence parameters, leaf soluble proteins content (LSPC) and productivity. The experiment was conducted on the field with five treatments, which were the application of the following herbicides: bentazon (720 g ha-1), fluazifop-p-butil (187.5 g ha-1), fomesafen (250 g ha-1) fluazifop-p-butil + fomesafen (187.5 + 250 g ha-1), and a manually weeded control treatment without herbicide application, in a randomized block design with four replications. Bentazon was the only herbicide causing significant reductions, but only until the first day after herbicide application (DAA), on the following...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Phaseolus vulgaris L.; Chlorophyll a fluorescence; Photosystems; Photoinhibition.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100291
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Response of spores and young gametophytes of Cyathea delgadii Sternb. (Cyatheaceae) and Blechnum brasiliense Desv. (Blechnaceae) to different light levels Acta Botanica
Hiendlmeyer,Rosane; Randi,Aurea Maria.
Light is a limiting factor for fern stablishment because it controls germination of light sensitive spores. The aim of this work was to study the effect of light levels on spore germination in two ornamental ferns native to the Atlantic forest, under natural conditions. Cyathea delgadii is a tree fern and Blechnum brasiliense, a subarborescent fern. The effect of light levels was analyzed in April and July/2003, in Florianópolis, Santa Catarina state, Brazil. Sterilized spores were sown in Erlenmeyer flasks containing mineral culture medium with macronutrients, iron, and benomyl 0.01%. The Erlenmeyer flasks were kept in 50 cm³ boxes covered with black shade netting, which gave 5, 22, 42, and 62% natural light. Irradiance and temperature were scored daily...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Ferns; Germination; Light levels; Photoinhibition; Spores.
Ano: 2007 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062007000400015
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Sugarcane yellow leaf virus infection leads to alterations in photosynthetic efficiency and carbohydrate accumulation in sugarcane leaves Trop. Plant Pathol.
Gonçalves,Marcos C.; Vega,Jorge; Oliveira,Jurandi G.; Gomes,Mara M. A..
Infection by Sugarcane yellow leaf virus (ScYLV) causes severe leaf symptoms in sugarcane (Saccharum spp.) hybrids, which indicate alterations in its photosynthetic apparatus. To gain an overview of the physiological status of infected plants, we evaluated chlorophyll a fluorescence and gas exchange assays, correlating the results with leaf metabolic surveys, i.e., photosynthetic pigments and carbohydrate contents. When compared to healthy plants, infected plants showed a reduction in potential quantum efficiency for photochemistry of photosystem (PSII) and alterations in the filling up of the plastoquinone (PQ) pool. They also showed reduction in the CO2 net exchange rates, probably as a consequence of impaired quantum yield. In addition, reductions were...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Luteoviridae; Carbon metabolism; Photoinhibition; Virus symptoms.
Ano: 2005 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-41582005000100002
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Theory of turbid microalgae cultures. ArchiMer
Martinez, Carlos; Mairet, Francis; Bernard, Olivier.
Microalgae can be cultivated in closed or open photobioreactors (PBR). In these systems, light rapidly decreases as it passes through the culture due to the turbidity of the medium. Thus, microalgae experiment different light intensities depending on their position in the medium. In this paper, we study theoretically how the growth rate of microalgae is affected by different factors; incident light intensity, form of the PBR, microalgae population density, turbidity of non-microalgae components, and light path-length of the reactor. We show that for different types of PBR the average growth rate is completely determined by the incident light intensity and the optical depth. In the case of vertical cylindrical PBRs illuminated from above (e.g. race-way or...
Tipo: Text Palavras-chave: Photobioreactor; Optical depth; Photoinhibition; Light limitation; Turbidity; Modelling.
Ano: 2018 URL: https://archimer.ifremer.fr/doc/00450/56133/57675.pdf
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