Consulta: subjectFacets:"Water potential"
Registros recuperados: 30
Data/hora: 09/06/2024 04:18:15

Procesos fisiológicos y contenido de polisacáridos estructurales en nopalito (Opuntia spp.) y su modificación por el potencial de agua del suelo
Provedor de dados: 32
Autores: García Ruiz, Mayra Teresa.
Se evaluaron los cambios de acidez titulable a lo largo de 24 h, de las yemas vegetativas con longitud media de 0.5 cm y nopalitos de 6 y 11 cm, de Opuntia ficus-indica de los cultivares Atlixco, Copena V1, Milpa Alta, Moradaza y Solferino, con riego. También se evaluó el efecto de la disminución del potencial de agua (ΨA) del suelo, por suspensión del riego durante 60 días, en condiciones de invernadero, en el potencial osmótico (ΨS ), liberación de electrolitos (o índice de daño membranal, Id) y contenido de polisacáridos estructurales de los nopalitos de esos cinco cultivares y una recolecta silvestre de O. streptacantha. La acidez de las yemas vegetativas y los nopalitos fluctuó entre 0.2 y 0.9 % a lo largo de las 24 horas del día, con las...
Tipo: Tesis
Palavras-chave: Acidez titulable; Potencial hídrico; Potencial osmótico; Polisacáridos; Maestría; Fisiología Vegetal; Tritable acidity; Water potential; Osmotic potential; Polysaccharides.
Ano: 2007
URL: http://hdl.handle.net/10521/1654

PHYSIOLOGICAL RESPONSES OF COFFEE TREE UNDER DIFFERENT IRRIGATION LEVELS
Provedor de dados: 70
Autores: Costa,Jéfferson de O.; Coelho,Rubens D.; Barros,Timóteo H. da S.; Fraga Júnior,Eusímio F.; Fernandes,André L. T.
ABSTRACT The plant water potential and the leaf temperature are physiological responses of the coffee tree that can be used as indicative of the irrigation management of this crop. There is a dependence between the leaf water potential with the potential matrix of the soil solution, however, the water potential levels found for the coffee tree show divergent relationships in the literature regarding the matrix potential. The objective of this study is to verify the water potential and leaf surface temperature in the coffee tree when submitted to different irrigation levels. The study was conducted in Piracicaba, SP, Brazil, using Coffea arabica species from Red Catuaí IAC 144 variety, the drip irrigation system was adopted and the management done by...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Coffea arabica; Leaf temperature; Water potential.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162018000500648

Different photoprotective responses under drought conditions of two predominant Chilean swamp forest species
Provedor de dados: 73
Autores: Bascuñán-Godoy,Luisa; Alcaíno,Claudia; Carvajal,Danny Eduardo; Sanhueza,Carolina; Montecinos,Sonia; Maldonado,Antonio.
Myrceugenia exsucca (DC.) O.Berg (Myrtaceae) and Luma chequen (Molina) A. Gray (Myrtaceae) are two predominants species from swamp forests of Chile. These species present differential microhabitat distribution across soil moisture and north-south precipitation gradients, with only L. chequen being commonly found in lower moisture sites. It is hypothesized that L. chequen has greater plasticity than M. exsucca in the attributes involved in photoprotection under drought conditions. To test this hypothesis: both species were exposed to short term drought treatment. A group of individuals was maintained irrigated (with &lt;img border=0 width=41 height=36 id="_x0000_i1084" src="http://fbpe/img/gbot/v70n2/art08-for1.jpg"...
Tipo: Journal article
Palavras-chave: Thermal dissipation; Water potential; Native plants; Myrtaceae family; Wetland plants.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432013000200008

Contribuicao hidrica do cerrado para as grandes bacias hidrograficas brasileiras.
Provedor de dados: 14
Autores: LIMA, J. E. F. W.; SILVA, E. M. da.
bitstream/CPAC-2009/24358/1/p2002_21.pdf
Tipo: Fôlder / Folheto / Cartilha (INFOTECA-E)
Palavras-chave: ECAGUA100; Brasil; Savanna.; Bacia Hidrográfica; Cerrado; Manejo de Água; Potencial Hídrico; Recurso Hídrico.; Brazil; Water potential; Water resources; Water management; Watersheds.
Ano: 2004
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/567621

Drought Research Priorities for the Dryland Tropics
Provedor de dados: 30
Autores: F.R.
Palavras-chave: Crops; Soil water; Transpiration (animals); Water balance; Weather hazards; Drought stress; Harvest index; Leaf area; Water potential.
Ano: 1988
URL: http://agropedia.iitk.ac.in/openaccess/?q=node/4045

Irrigation management in Latin America: present situation, problem areas and areas of potential improvement
Provedor de dados: 31
Autores: International Irrigation Management Institute (IIMI).
Tipo: Book
Palavras-chave: Irrigation management; Water potential; Irrigation systems; Social aspects; Economic aspects; Water users associations; Farm Management; Institutional and Behavioral Economics.
Ano: 1990
URL: http://purl.umn.edu/113951

Impact of management interventions on the performance of five irrigation schemes in Sri Lanka
Provedor de dados: 31
Autores: Imbulana,   K.A.U.S.; Merrey,   Douglas J.
This working paper is the outcome of a data collection process initiated under the advice of Dr. Shigeo Yashima of the International Irrigation Management Institute (IIMI). The objective of this data collection process was to make a preliminary assessment of irrigation performance in Sri Lanka using irrigation systems with different backgrounds to identify areas for further research.
Tipo: Working or Discussion Paper
Palavras-chave: Irrigation programs; Performance evaluation; Irrigation management; Intervention; Irrigation systems; Monitoring; Performance indexes; History; Farmers associations; Farmer participation; Farmer-agency interactions; Communication; Organizations; Water potential; Rice; Crop yield; Water supply; Land productivity; Rain; Data collection; Farm Management; Institutional and Behavioral Economics; Land Economics/Use.
Ano: 1995
URL: http://purl.umn.edu/113609

Impact of management interventions on the performance of five irrigation schemes in Sri Lanka
Provedor de dados: 31
Autores: Imbulana,   K. A. U. S.; Merrey,   D. J.
This working paper is the outcome of a data collection process initiated under the advice of Dr. Shigeo Yashima of the International Irrigation Management Institute (IIMI). The objective of this data collection process was to make a preliminary assessment of irrigation performance in Sri Lanka using irrigation systems with different backgrounds to identify areas for further research.
Tipo: Working or Discussion Paper
Palavras-chave: Irrigation programs; Performance evaluation; Performance indexes; Irrigation systems; Farmers associations; Farmer participation; Farmer-agency interactions; Water potential; Rice; Crop yield; Land productivity; Data collection; Crop Production/Industries; Farm Management; Land Economics/Use.
Ano: 1995
URL: http://purl.umn.edu/113605

Relações hídricas em espécies lenhosas no campus Pampulha/UFMG, Belo Horizonte, MG
Provedor de dados: 88
Autores: SILVA,BRUNO GUSMÃO; LEMOS FILHO,JOSÉ PIRES DE.
O presente trabalho objetivou avaliar as relações hídricas em função da demanda evaporativa e da densidade da madeira em Swietenia macrophylla King, Joannesia princeps Vell., Inga edulis Mart., Licania tomentosa (Benth.) Fritsch e Centrolobium tomentosum Guill. ex Benth. O potencial hídrico foi determinado com uma câmara de pressão e a condutância estomática, com porômetro de difusão na estação chuvosa, na estação seca e nas situações transicionais. J. princeps foi a espécie que apresentou maiores valores de potencial hídrico no "predawn" (psiPD &gt; - 0,25 Mpa), e I. edulis os menores valores (psiPD = - 1,5 MPa). J. princeps apresentou maiores valores de potencial hídrico durante o dia (psiMD &gt; - 1,5 MPa), e os menores valores foram observados em S....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Water potential; Conductance; Vapour pressure deficit; Wood density.
Ano: 2001
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042001000500006

Soil water energetic status and cowpea beans irrigated with saline water
Provedor de dados: 91
Autores: Oliveira,Wanderson J. de; Souza,Edivan R. de; Almeida,Brivaldo G. de; Silva,Ênio F. de F. e; Melo,Hidelblandi F. de; Leal,Lucas Y. C.
ABSTRACT The study of the water energetic status under saline condition and its impact on the development of cowpea is of extreme importance, since this crop is the food base in many parts of the world. An experiment was carried out in a greenhouse from March to May 2014 using the cultivar IPA 206 in Fluvisol collected in the municipality of Pesqueira, PE, Brazil. Waters with six levels of electrical conductivity (0; 2.5; 5; 7.5; 10; 12.5 dS m-1) formulated with NaCl and a salt mixture were used. The experiment was conducted in randomized blocks in a 6 x 2 factorial arrangement with four replicates, forming 48 experimental plots. The matric, osmotic and total potential of water in the soil, the osmotic, and water potential in the plant and atmospheric...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Water potential; Osmotic potential; Vigna unguiculata.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662016000800685

Water status and gas exchange of umbu plants (Spondias tuberosa Arr. Cam.) propagated by seeds and stem cuttings
Provedor de dados: 94
Autores: Lima Filho,José Moacir Pinheiro.
The experiment was carried out at the Embrapa Semi-Árido, Petrolina-PE, Brazil, in order to study the physiological responses of umbu plants propagated by seeds and by stem cuttings under water stress conditions, based on leaf water potential and gas exchange measurements. Data were collected in one-year plants established in pots containing 30 kg of a sandy soil and submitted to twenty-day progressive soil water deficit. The evaluations were based on leaf water potential and gas exchange data collection using psychrometric chambers and a portable infra-red gas analyzer, respectively. Plants propagated by seeds maintained a significantly higher water potential, stomatal conductance, transpiration and photosynthesis under decreasing soil water availability....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Water potential; Stomatal conductance; Transpiration; Photosynthesis; Root tubers.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452007000200032

Response mechanisms of Brachiaria brizantha cultivars to water deficit stress
Provedor de dados: 96
Autores: Santos,Patricia Menezes; Cruz,Pedro Gomes da; Araujo,Leandro Coelho de; Pezzopane,José Ricardo Macedo; Valle,Cacilda Borges do; Pezzopane,Cristiana de Gaspari.
Two cultivars of Brachiaria brizantha (Hochst ex. A. Rich) Stapf. (Syn. Urochloa) were evaluated for their adaptation to water deficit and the stress response mechanisms in a greenhouse experiment. The experimental design was in completely randomized blocks with a 2 × 2 × 4 factorial arrangement. The Marandu and BRS Piatã cultivars were evaluated under two water availability conditions, with or without water restriction. The harvests were carried out 0, 7, 14 and 28 days after the start of water restriction. For both cultivars, the water deficit stress caused a reduction in shoot biomass and leaf area and an increase in the percentage of roots in the deeper soil layers. The B. brizantha cv. Marandu reached critical levels of leaf water potential in a...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: BRS Piatã; Marandu; Osmotic potential; Water availability; Water potential.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982013001100001

Physiological responses and production of 'Syrah' vines as a function of training systems
Provedor de dados: 63
Autores: Favero,Ana Carolina; Amorim,Daniel Angelucci de; Mota,Renata Vieira da; Souza,Claudia Rita de; Regina,Murillo de Albuquerque.
Plant architecture and its interaction with agricultural practices and environmental constraints is determinant for grapevine canopy structure, which is related to carbon assimilation, bud fertility and fruit quality. In this context, this study evaluated the performance of field-grown 'Syrah' grapevines conducted by two management systems: Vertical Shoot Position (VSP) or a modified Geneva Double Curtain (GDC), in Pirapora, state of Minas Gerais, Brazil, during the winters of 2007 and 2008. The evaluations of leaf area, water relations and net CO2 assimilation were made at the end of the ripening period. Yield per vine and per hectare were estimated and mean berry weight and diameter, total soluble solids, pH and titratable acidity were evaluated during...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: CO2 assimilation; Canopy management; Water potential; Berry temperature; Fruit quality.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162010000300003

Water relations in seed biology
Provedor de dados: 63
Autores: Villela,F. A.
The water relations play a fundamental role in seed biology. Thus, the purpose of the present paper was to analyze the performance of water status in seed development and germination. The researches have suggested that the water potential of the seed or seed structures provides a better indicator of the seed water status than water content. The seed water status plays a regulatory role in seed development and germination.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Water status; Hydration levels; Water potential.
Ano: 1998
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90161998000500018

Germination of cotton cultivar seeds under water stress induced by polyethyleneglycol-6000
Provedor de dados: 63
Autores: Meneses,Carlos Henrique Salvino Gadelha; Bruno,Riselane de Lucena Alcântara; Fernandes,Pedro Dantas; Pereira,Walter Esfrain; Lima,Leonardo Henrique Guedes de Morais; Lima,Marleide Magalhães de Andrade; Vidal,Márcia Soares.
The physiological quality of cotton cultivar seeds (Gossypium hirsutum var. latifolium L.) was evaluated in laboratory by the simulation of water potentials with polyethyleneglycol-6000 (0.0; -0.2; -0.4; -0.6; -0.8 and -1.0 MPa), at 25ºC using germitest paper as substrate. A completely randomized design in a 4 × 6 factorial scheme with four replications of 50 seeds each was used. The studied variables were: germination percentage, first count of germination, germination velocity index, accelerated aging in water, electrical conductivity, humidity, vigor classification, radicle length and radicle/shoot length ratio. The effect of water stress on seed viability and on plantlet vigor was severe at potentials below -0.4 MPa. The 'CNPA 187 8H' cultivar was the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Gossypium hirsutum var. latifolium L.; PEG-6000; Vigor; Water potential.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162011000200001

Electrical conductivity and soybean seedling emergence
Provedor de dados: 63
Autores: Colete,Julio Cesar Fachini; Vieira,Roberval Daiton; Dutra,Alek Sandro.
Evaluation of soybean [Glycine max (L.) Merrill] seeds vigor and its relation with field seedling emergence can provide secure indicatives of seed physiological potential. The present research studied the relationship between the electrical conductivity test and the seedling emergence of soybean in field and laboratory. The field experiment was sown in November 26th, December 3td and 10th, 2000. Laboratory tests were performed using levels of water potential in the substrate (soil) -0.03; -0.2; -0.4; and -0.6 MPa. Fourteen seed lots, seven of 'Embrapa 48' and seven of 'BRS 133' soybean cultivars were used. Laboratory tests comprised seed water content determination, before and after the accelerated aging; germination and vigor tests (accelerated aging and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glycine max; Seed analysis; Water content; Vigor; Water potential.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162004000400006

Anatomical root variations in response to water deficit: wild and domesticated common bean (Phaseolus vulgaris L)
Provedor de dados: 48
Autores: Peña-Valdivia,Cecilia B; Sánchez-Urdaneta,Adriana B; Meza Rangel,Joel; Juárez Muñoz,Juana; García-Nava,Rodolfo; Celis Velázquez,Raquel.
Root anatomical responses to water deficit are diverse and regulation of water uptake strongly depends on plant anatomy. The ancestors of common bean (Phaseolus vulgaris L.) cultivars are the wild common beans. Because wild beans adapt and survive well in theon atural environment, it is hypothesized that wild common bean roots are less affected than those of domesticated beans at low substrate water potential (&amp;#968;W). A wild common bean accession from Chihuahua Mexico and cv. Bayomex were studied. Seedlings with a mean root length between 3 and 4 cm were maintained for 24 h in vermiculite at &amp;#968;W of -0.03 (well hydrated), -0.65, -1.48 and -2.35 MPa (partially dry). Ten anatomical characteristics of differentiation and cell division in root...
Tipo: Journal article
Palavras-chave: Endodermis; Protoderm; Seedlings; Water potential; Xylem.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602010000400006

Photosynthetic capacity and water use efficiency in sugarcane genotypes subject to water deficit during early growth phase
Provedor de dados: 52
Autores: Silva,Marcelo de Almeida; Jifon,John Lonfover; Santos,Claudiana Moura dos; Jadoski,Cleber Junior; Silva,Jorge Alberto Gonçalves da.
The objective of this study was to compare the gas exchange, photosynthetic capacity and water potential of sugarcane genotypes cultivated under water deficit conditions imposed during the initial growth phase. Experiments were performed in a greenhouse using two sugarcane genotypes namely: HoCP93-776 (drought susceptible) and TCP02-4587 (drought tolerant). Sixty days after planting, two different water treatments were applied (i.e., with or without water deficit). At 0,30 and 60 days after the treatment, gas exchange variables were evaluated for their relationship with water use, intrinsic instantaneous water use efficiency and instantaneous carboxylation efficiency. The SPAD index, photosynthetic pigments, water potential and relative water content in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Saccharum spp.; Photosynthesis; Stomatal conductance; Chlorophyll; Drought tolerance; Water potential.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132013000500004

Water osmotic absorption in Coleus blumei plants under salinity stress
Provedor de dados: 52
Autores: Sena,José Ozinaldo Alves de; Zaidan,Humberto Actis; Castro,Paulo Roberto de Camargo e.
Three month old Coleus blumei plants in pots were treated with different NaCl concentrations: 0.00, 0.25, 0.50 and 1.00%. To determine the water osmotic absorption, the plants had their stems cut at 10 cm from the soil surface. The remaining stems were linked to glass tubes by flexible rubber tubes. Readings of the water column level in the glass tubes were performed at each 30 minutes, corresponding to the water osmotic absorption, with a total of eleven readings. Other Coleus blumei, with the same age, received the NaCl concentrations, and were evaluated under field conditions in terms of transpiration and stomatal resistance. A randomized complete block analysis was used with five replications. An increase of osmotic absorption was verified for all...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Water relations; Water potential; Transpiration; Stomatal resistance.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132006000700001

Ecophysiology of tea
Provedor de dados: 61
Autores: 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

Ecophysiology of coconut palm under water stress
Provedor de dados: 61
Autores: Gomes,Fábio P.; Prado,Carlos H.B.A.
Coconut palm is of great social and economic importance for millions of people in the tropics and subtropics. Drought is one of the main environmental factors that limit coconut productivity. In this review, physiological and morphological data are presented in an integrated perspective to provide a holistic view of the behavior of coconut trees facing water deficit under both field and controlled conditions. Great capacity to produce homorhizic roots capable of searching continuously for water and nutrients and high protoplasmic tolerance in leaves allows the coconut tree to endure water deficit. High membrane stability, osmoprotection, osmoregulation and enhanced activity of antioxidant enzymes are characteristics often found in leaves of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cocus nucifera; Desiccation tolerance; Leaf gas exchange; Leaf water relations; Net photosynthesis; Osmotic potential; Water potential; Water-use efficiency.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000400008

Water relations and organic solutes production in four umbu tree (Spondias tuberosa) genotypes under intermittent drought
Provedor de dados: 61
Autores: Silva,Elizamar C.; Nogueira,Rejane J. M. C.; Vale,Fernando H. A.; Melo,Natoniel F. de; Araújo,Francisco P. de.
In order to evaluate changes in leaf water potential (ψw) and solute accumulation induced by intermittent drought, an research was performed under greenhouse conditions using four umbu tree genotypes (GBU 44, GBU 48, GBU 50 and GBU 68) and two water treatments (control and stressed by withholding water), with four replicates. The ψw was measured in four-hour intervals during a 24-hour period at the first stomatal closure and at the end of the experimental period. Carbohydrates, amino acids, protein and proline contents were also evaluated in leaves and roots. Significant differences were found in most of the studied parameters. The lower ψw hour was between 800 h and 1200 h. GBU 50 reduced significantly ψw in stressed plants at 800 h, while control plants...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Carbohydrates; Proline; Spondias tuberosa; Water potential.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202009000100006

Physiological response of oil palm interspecific hybrids (Elaeis oleifera H.B.K. Cortes versus Elaeis guineensis Jacq.) to water deficit
Provedor de dados: 61
Autores: Méndez,Yurany Dayanna Rivera; Chacón,Leonardo Moreno; Bayona,Cristihian Jarry; Romero,Hernán Mauricio.
Water supply is the main yield-limiting abiotic factor of oil palm in Colombia. To determine the effect of water deficit on the physiology of oil palm and to assess the tolerance degree to this condition, interspecific Elaeis oleifera versus Elaeis guineensis 'U1273', 'U1859', 'U1914', and 'U1937' hybrids were planted for 60 days in soil with different water potentials (-0.042, -0.5, -1.0, and -2.0 MPa) in a complete randomized factorial design with three replications. The water potential, osmotic adjustment molecules (total and reducing sugar content), gas exchange (photosynthesis rate, stomatal conductance, water use efficiency, and leaf respiration), and vegetative growth (height, bulb diameter, leaf area, number of leaves, total dry matter, and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ecophysiology; Growth; Stress; Tolerance; Water potential.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202012000400006

Ecophysiological studies of two andean forest contrasting species Abatia parviflora and Myrcianthes leucoxyla under Bogotá conditions, Colombia
Provedor de dados: 61
Autores: Colmenares-Trejos,Sara L.; Melgarejo,Luz Marina; Romero A.,Hernán Mauricio.
The physiological response of high Andean forest contrasting plants, Myrcianthes leucoxyla, a shadow-facultative heliophyte, and Abatia parviflora, a heliophyte, was studied during the transition from dry season to wet season in Bogotá. Light response curves (A-PAR), water potential (Ψw), transpiration rate (E), stomatal conductance (gs), leaf soluble protein content and peroxidase activity were measured in this study in a 48h cycle. The values for E, gs, Ψw and Ψw predawn for M. leucoxyla were 0.07 to 4.89 µg/cm s, 0.02 to 0.5 cm s-1, -0.025 to -1.05 MPa, and-0.1 MPa, respectively. For A. parviflora E, gs, Ψw and Ψw predawn were 0.47 to 12.27 µg/cm s, 0.17 to 1.42 cm s-1, -0.05 to -0.3 MPa and -0.075 MPa, respectively. A. parviflora presented a tendency...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: A-PAR curves; Gas exchange; Heliophyte; Shadow plant; Water potential.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202011000400008

Growth evaluation and water relations of Erythrina velutina seedlings in response to drought stress
Provedor de dados: 61
Autores: Silva,Elizamar Ciríaco da; Silva,Marcos F. A.; Nogueira,Rejane J. M. C.; Albuquerque,Manoel B.
Erythrina velutina Willd. (common name: mulungu) is a deciduous, heliophyte found in the semi-arid region of northeastern Brazil. To evaluate the growth and water relations of mulungu seedlings in soils with different degrees of moisture content, an experiment was carried out under greenhouse conditions using four water treatments (100%, 75%, 50% and 25% of the field capacity- FC). Predawn (Ψpdw) and midday leaf water potential (Ψmdw), relative water content (RWC), plant height, number of leaves, stem diameter, leaf area (LA), specific leaf area (SLA), leaf area ratio (LAR), dry matter in different organs, biomass partitioning and root:shoot ratio were evaluated. No differences were detected between treatments for Ψpdw after 30 days; however, at midday,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Biomass allocation; Dry matter; Leaf area; Root to shoot ratio; Relative water content; Water potential.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202010000400002

Variation of water potential and trunk diameter answer as sensitivity to the water availability in table grapes
Provedor de dados: 117
Autores: Silva-Contreras,Claudio; Sellés-Von Schouwen,Gabriel; Ferreyra-Espada,Raul; Silva-Robledo,Herman.
Variation in trunk diameter (TDV) has been proposed as an indicator of the water status of grape vines, with apparently contradictory results. In Vitis vinifera L. var. Crimson Seedless we evaluated the water potential (&amp;#936;), an indicator normally used to determine the water status of grapes, and TDV, comparing two irrigation treatments which restored 100% or 50% of the ETc, to compare the sensitivity of these two indicators to a decrease in soil water. Two evaluation periods of 23 d each were used, the first during the exponential growth phase and the second in the post-veraison period, when the trunk stops growing. In both periods TDV showed coefficients of variation greater than 25%, compared to the 7-10% recorded for water potential. However,...
Tipo: Journal article
Palavras-chave: Water potential; Variable displacement sensor; Sensitivity; Itis vinifera.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400001

Increased Growth and Changes in Wheat Mineral Composition through Calcium Silicate Fertilization under Normal and Saline Field Conditions
Provedor de dados: 117
Autores: Anser,Ali; Basra,Shahzad M.A; Hussain,Safdar; Iqbal,Javaid.
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Tipo: Journal article
Palavras-chave: Salt stress; Silicon; Wheat growth; K+:Na+; Water potential; Stomatal conductance.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100016

Analysis of Hydraulic Conductance Components in Field Grown, Mature Sweet Cherry Trees
Provedor de dados: 117
Autores: Oyarzún,Ricardo; Stöckle,Claudio; Whiting,Matthew.
As a necessary step towards understanding soil water extraction and plant water relationships, the components of hydraulic conductance (K) of mature sweet cherry (Prunus avium L.) trees were evaluated in situ based on a Ohm´s law analog method. In June 2004, K was determined for 10-yr-old ‘Bing’/‘Gisela® 5’ trees, from simultaneous measurements of whole canopy gas exchange and leaf (sunlit and shaded) and stem water potentials (&amp;#936;). Leaf water potential of sunlit leaves was lower than shaded leaves, reaching minimum values of ca. -2.3 MPa around 14:00 h (solar time). Average total hydraulic conductance was 60 ± 6 mmol s-1 MPa-1, presenting a slight decreasing trend as the season progressed. The analysis of tree K components showed that it was...
Tipo: Journal article
Palavras-chave: Plant water relations; Transpiration; Water potential; Whole-canopy gas exchange.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392010000100006

Effect water activity on in vitro mycelial growth of Neofusicoccum spp. infecting blueberry
Provedor de dados: 118
Autores: Latorre,Bernardo A; Díaz,Gonzalo A; Reed,María P.
Stem canker in blueberries (Vaccinium corymbosum L.) is a disease which is widely distributed around the world and of growing importance in Chile, associated with Neofusicoccum species. The purpose of the present work was to study the effects of water activity (a w) and temperature on mycelial growth in vitro of N. arbuti, N. australe and N. parvum, obtained from blueberries with symptoms of stem canker. According to the results obtained, 25 °C was the optimum temperature for mycelial growth of N. arbuti, N. australe and N. parvum. These species presented minimal growth at 35 °C and none at 0 and 5 °C. The effect of a w on mycelial growth was significant (P&amp;#8804;0.001) and varied with the species of Neofusicoccum and the temperature. At 25 °C, the...
Tipo: Journal article
Palavras-chave: Ecological determinants; Neofusicoccum arbuti; Neofusicoccum australe; Neofusicoccum parvum; Stem canker; Dieback; Vaccinium; Water potential.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202012000100019

Mitigating effect of salicylic acid and nitrate on water relations and osmotic adjustment in maize, cv. Lluteño exposed to salinity
Provedor de dados: 118
Autores: Escobar,Hugo; Bustos,Richard; Fernández,Felipe; Cárcamo,Henry; Silva,Herman; Frank,Nicolás; Cardemil,Liliana.
We analyzed the mitigating effect of NO3 - and salicylic acid (SA) on the detrimental effects of salt stress by studying the water status of plants of maize grown in Hoagland's medium with NaCl 100 mM as the saline component, to which SA and NO3 - were added in different concentrations as mitigating agents. We evaluated water potential &amp;#936;w, osmotic potential &amp;#936;s, relative water content (RWC), turgor potential (&amp;#936;p ), and the osmotic adjustment (OA) of leaves and roots. SA 0.5 mM mitigated the effects of salinity by increasing the &amp;#936;w of the leaf, the &amp;#936;sof theroot, the &amp;#936;pof the leaf, RWC and OA of the leaf; while NO3 was only effective in combination with SA, mitigating the effects of salinity by increasing...
Tipo: Journal article
Palavras-chave: Nitrate; Osmotic potential; Osmotic adjustment; Salinity mitigation; Salicylic acid; Water potential; Water relative content.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202010000300006