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| Registros recuperados: 35 | |
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| Souza,Daniely F. S. de; Pinto,João V. de N.; Costa,Deborah L. P.; Vieira,Igor C. de O.; Silva,Thieres G. F. da; Souza,Paulo J. de O. P. de. |
| ABSTRACT The objective of this study was to analyze the variations of the decoupling factor and the aerodynamic and stomatal conductances for cowpea subjected to different levels of water availability during the reproductive phenological stages of the crop. The study was conducted in the municipality of Castanhal located in the northeast of the state of Pará, Brazil, in an area planted with cowpea, in 2013, 2014 and 2015 with four irrigation treatments: T100 - replacement of 100% of the crop evapotranspiration (ETc); T50 - replacement of 50% ETc; T25 - replacement of 25% ETc; and T0 - without any replacement (without irrigation). The interaction between the crop and the atmosphere in water vapor exchange was estimated through the decoupling factor (Ω),... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Vigna unguiculata (L.) Walp; Decoupling factor; Aerodynamic conductance; Stomatal conductance. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662019001000725 |
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| Verryckt, Lore T.; Van Langenhove, Leandro; Ciais, Philippe; Courtois, Elodie A.; Vicca, Sara; Peñuelas, Josep; Stahl, Clément; Coste, Sabrina; Ellsworth, David S.; Posada, Juan M.; Obersteiner, Michael; Chave, Jérôme; Janssens, Ivan A.. |
| Measuring leaf gas exchange from canopy leaves is fundamental for our understanding of photosynthesis and for a realistic representation of carbon uptake in vegetation models. Since canopy leaves are often difficult to reach, especially in tropical forests with emergent trees up to 60 m at remote places, canopy access techniques such as canopy cranes or towers have facilitated photosynthetic measurements. These structures are expensive and therefore not very common. As an alternative, branches are often cut to enable leaf gas exchange measurements. The effect of branch excision on leaf gas exchange rates should be minimized and quantified to evaluate possible bias. We compared light‐saturated leaf net photosynthetic rates measured on excised and intact... |
| Tipo: Text |
Palavras-chave: Branch cutting; Canopy physiology; French Guiana; Gas exchange; Photosynthesis; Rainforest; Stomatal conductance. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00613/72466/71949.pdf |
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| Streck,Nereu Augusto. |
| The reduction of crop growth and yield in dry areas is largely due to stomatal closure in response to dry soil, which decreases photosynthesis. However, the mechanism that causes stomatal closure in a drying soil is a controversial issue. Experienced and respected plant physiologists around the world have different views about the primary sensor of soil water shortage in plants. The goal of this review is to present a chronological synthesis about the evidence of the possible candidates for the mechanism by which plants sense a drying soil. Hydraulic signals in the leaves as the mechanism that causes stomatal closure dominated the view on how plants sense a drying soil during the 70s and the early 80s. In the middle 80s, studies suggested that stomatal... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil water; Plant water; Water stress; Stomatal conductance. |
| Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782004000200039 |
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| Rakocevic, Miroslava; Sturion, José Alfredo; Medrado, Moacir José Sales; Lavoranti, Osmir José; Mosele, Sérgio Henrique; Valduga, Alice Tereza. |
| The aims of this study were to estimate the genetic parameters for 59 half-sib progenies of maté under runing for formation, and to evaluate the ecophysiological properties for four progenies (P15, P18, P41 e 47) and two controls (P61 and P62), components of one maté breeding experiment combining rovenances and progenies, established in Erechim, RS. The ecophysiological properties (stomatal onductance (gs) - mol m-2s-1, net photosynthesis (A) - μmol CO2 m-2s-1, and transpiration (E) -mmol H2O - s-1) were measured during one year in five epochs (from September 2002 to August 2003). The variance omponents, genetic and phenotypic parameters and genetic values (for data of foliar mass collected in runing of formation) were obtained using a... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Genetic value; Heritability; Photosynthesis; Stomatal conductance; Transpiration. Condutância estomática; Fotossíntese; Herdabilidade; Transpiração; Valor genético.. |
| Ano: 2011 |
URL: http://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/229 |
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| Mejía-de Tafur,María Sara; Riaño-Herrera,Néstor Miguel; Urrego-Mesa,John Byron; Ibarra-Espinosa,Dora Mónica; Zapata-Duque,Claudia Marcela. |
| Abstract Two outdoor trials were conducted in the department of Valle del Cauca, Colombia, in contrasting climatic conditions, to evaluate the effect of soil water availability on the gas exchange of four elite genotypes of Eucalyptus grandis as follows: 28-3, 18-3, 24A-5 and 19-1, respectively. One trial was conducted on the campus of the Universidad Nacional de Colombia located in Palmira, at 994 m.a.s.l. with an average temperature of 23.5°C (maximum of 31°C, minimum of 18°C), and 76% relative humidity (RH). The second trial was conducted at the nursery of Carton de Colombia S.A., located in Restrepo, at 1450 m.a.s.l. with an average temperature 18°C (maximum of 26°C, minimum of 12°C) and 80% RH. A split-plot design with four replicates was used.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Water stress; Waterlogging; Stomatal conductance; Photosynthesis; Transpiration. |
| Ano: 2017 |
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122017000400549 |
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| Zheng,Ming; Bai,Yungang; Zhang,Jianghui; Liu,Hongbo; Ding,Ping. |
| ABSTRACT In grape, high temperatures and low humidity prolong midday depression of foliar photosynthesis and dramatically reduce fruit yield. In this study, we explored the effects of various mist micro-spray treatments on grape photosynthesis at a test site in Shanshan County (N, 42.91°; E, 90.30°), Turpan, Xinjiang, China. We tested four different mist micro-spray durations including 1 h (WP1), 2 h (WP2), 3 h (WP3), and 0 h (CK). WP1, WP2, and WP3 affected canopy air temperature and humidity for 5 h, 7 h, and 9 h, respectively. At 12:30, WP1, WP2, and WP3 had the strongest cooling effect and altered temperature by −5.12 °C, −5.09 °C, and −5.17 °C respectively. The relative chlorophyll content was higher in the upper than the lower canopy leaves. There... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Air temperature; Chlorophyll; Photosynthesis; Stomatal conductance; Transpiration rate. |
| Ano: 2021 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162021000100039 |
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| Dalmolin,Ândrea Carla; Dalmagro,Higo José; Lobo,Francisco de Almeida; Antunes Junior,Mario Zortéa; Ortíz,Carmen Eugenia Rogríguez; Vourlitis,George Louis. |
| Vochysia divergens Pohl (commonly known as cambara) is a pioneer tree species that is native to the Amazon Basin but has been invading the seasonally flooded wetlands of the Brazilian Pantanal, forming monospecific communities. The physiological aspects associated with cambara invasion, including the effects of flooding and shading on growth and leaf gas exchange, are unknown but may shed light on why cambara is able to invade this novel habitat so rapidly. Thus, we conducted a manipulative experiment to quantify the effects of shading and flooding on the growth, gas exchange and leaf nutrient content of V. divergens saplings. Based on previous research we hypothesized that (1) experimental flooding would have no effect on the growth and gas exchange of V.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cambara; Physiological stress; Photosynthesis; Plant ecophysiology; Stomatal conductance; Tropical wetlands. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202012000200001 |
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| Silveira,Helbert Rezende de Oliveira; Souza,Kamila Rezende Dázio de; Alves,Jose Donizeti; Santos,Meline de Oliveira; Andrade,Cínthia Aparecida; Bomfim,Sandro Costa. |
| Irrigation has enhanced coffee production in several regions of Brazil. However, with the increase in irrigated crop areas, problems related to the frequent and poorly planned usage of irrigation may arise. Since there are few studies related to the physiological alterations in coffee plants exposed to water excess, we evaluated the effects of waterlogging on metabolism and partitioning of carbohydrates, levels of photosynthetic pigments and gas exchange in seedlings of two commercial coffee cultivars (Mundo Novo and Catuaí). After acclimation, seedlings with eight pairs of fully expanded leaves were cultivated under three water availability conditions: field capacity, intermittent waterlogging and continuous waterlogging. Gas exchange and the levels of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Water excess; Photosynthesis; Reducing sugars; Stomatal conductance; Water efficiency use.. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542015000200138 |
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| Lima Filho,José Moacir Pinheiro. |
| A study was carried out at Embrapa Semi-Árido, Petrolina-PE, Brazil, aiming to understand the gas exchange process of the umbu tree (Spondias tuberosa Arr. Cam.) in the dry and rainy seasons. Stomatal conductance, transpiration, photosynthesis and internal CO2 concentration were obtained with a portable infrared gas analyzer (IRGA). During the dry season the umbu tree showed a much lower stomatal conductance early in the morning, as soon as the vapor pressure deficit increased, apparently affecting CO2 assimilation more than transpiration. The highest values were detected around 6:00 am but decreased to the lowest points between 10:00 am and 2:00 pm. During the rainy season, however, stomatal conductance, transpiration and photosynthesis were significantly... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Spondias tuberosa; Stomatal conductance; Transpiration; Photosynthesis; CO2 internal concentration. |
| Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452004000200006 |
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| Alvarez,Rita de Cássia Félix; Crusciol,Carlos Alexandre Costa; Nascente,Adriano Stephan; Rodrigues,João Domingos; Habermann,Gustavo. |
| The objective of this work was to evaluate gas exchange rates, plant height, yield components, and productivity of upland rice, as affected by type and application time of plant growth regulators. A randomized block design, in a 4x2 factorial arrangement, with four replicates was used. Treatments consisted of three growth regulators (mepiquat chloride, trinexapac-ethyl, and paclobutrazol), besides a control treatment applied at two different phenological stages: early tillering or panicle primordial differentiation. The experiment was performed under sprinkler-irrigated field conditions. Net CO2 assimilation, stomatal conductance, plant transpiration, and water-use efficiency were measured four times in Primavera upland rice cultivar, between booting and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Oryza sativa; Net photosynthesis; Stomatal conductance; Transpiration; Water-use efficiency. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2012001000007 |
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| Tucci,Maria Luiza Sant'anna; Modolo,Valéria Aparecida; Erismann,Norma de Magalhães; Machado,Eduardo Caruso. |
| The close relationship between the chlorophyll-meters readings and the total chlorophyll and nitrogen contents in leaves, has allowed their evaluation both in annual and perennial species. Besides, some physiological events such as the CO2 assimilation have also been estimated by chlorophyll meters. This work was carried out aiming to evaluate the gas exchanges of peach palms as a function of the chlorophyll SPAD-Meter readings. Three year-old peach palms from Yurimaguas, Peru were studied in Ubatuba, SP, Brazil, spaced 2 x 1 m in area under a natural gradient of organic matter which allowed four plots to be considered, according to the peach palms leaves colors, from light yellow to dark green. The SPAD readings and the stomatal frequency of leaflets were... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bactris gasipaes Kunth; CO2 assimilation; Stomatal conductance. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452011000500033 |
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| Scambato,Agustina A.; Echeverria,Mariela; Sansberro,Pedro; Ruiz,Oscar A.; Menéndez,Ana Bernardina. |
| The present work was aimed at testing the hypothesis that mycorrhizal Prosopis alba, an economically important tree species worldwide, presents increased salt-tolerance compared with non-mycorrhizal ones and at gaining insight into the possible mechanisms underlying that improvement. For this purpose, a randomized complete block experiment with two factors: mycorrhizal treatments with or without the arbuscular fungus Glomus intraradices and two salinity levels, 0 and 200 mM NaCl was performed. Plant growth in P. alba plants colonized by G. intraradices was less affected by salinity than that in non-arbuscular mycorrhizal (AM) plants, indicating that mycorrhizal colonization turned P. alba more tolerant to salinity. Photosynthesis was reduced by salinity in... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Photosynthesis; Salinity; Stomatal conductance; Transpiration ratio; Proline. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202010000400008 |
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| Dias,Ana S.; Lidon,Fernando C.; Ramalho,José C.. |
| In heat stressed genotypes of Triticum aestivum L. (Sever and Golia) and Triticum turgidum subsp. durum (Acalou and TE 9306), chosen according to its genetic background diversity, Ca and Mg accumulations were correlated with its photosynthetic performance. It was found that with high temperatures the concentrations of Ca increased in the shoots, whereas the accumulation of Mg augmented only in bread wheat genotypes. Under heat stress, the pattern of electrolytes release in Golia and Acalou remained similar, but the extrusion rates became higher in Sever. During grain filling, the levels of total chlorophylls decreased in the heat stressed genotypes (excepting in Sever). In all the Triticum genotypes, stomatal conductance and the net carboxilation rate... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Triticum aestivum L.; Triticum turgidum subsp. durum; Net photosynthesis; Nutrients uptake and translocation; Stomatal conductance. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202009000200005 |
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| CAMPOSTRINI,ELIEMAR; YAMANISHI,OSVALDO KIYOSHI. |
| Four papaya genotypes, two from the Solo group (Sunrise Solo TJ and Improved Sunrise Solo line 72/12) and two from the Formosa group (Tainung 02 and Know You 01) grown in ultisol under field conditions in Macaé, RJ, Brazil, were used in this study. Two different effective depths (ED) were determined in the area using a penetrographer with average soil moisture of 11.2%. The area with ED of 0.35 m with a maximum pressure of 4.12 MPa for penetration was defined as an area with restriction (WR) to root growth, while, the area with minimum ED of 0.60 m and a pressure lower than 2.30 MPa as an area with no restriction (NR). The net CO2 assimilation rate (A), stomatal conductance (g s), leaf temperature (Tl), intercellular partial pressure of CO2 (c i) and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Carica papaya L.; Photosynthesis; Leaf temperature; Stomatal conductance; Intrinsic water use efficiency. |
| Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-31312001000200002 |
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| CAMPOSTRINI,ELIEMAR; YAMANISHI,OSVALDO KIYOSHI; MARTINEZ,CARLOS A.. |
| In this research, was used four papaya (Carica papaya L.) genotypes: three from the 'Solo ( Sunrise Solo TJ, Sunrise Solo 72/12 and Baixinho de Santa Amália) group and one from the 'Formosa' group (Know-You 01). They were grown in plastic pots containing a sandy-clay-loam soil subjected to pH correction and fertilization, under greenhouse conditions. Throughout the experimental period plants were subjected to periodic irrigation to maintain the soil humitidy around field capacity. The experiment was conducted 73 days after sowing. In all genotypes, leaf gas exchange characteristics were determined. The net photosynthetic rate (A, mumol m-2 s-1 ), stomatal conductance (g s mol m-2 s-1), leaf temperature (T I, 0C) and intercellular carbon dioxide... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Photosynthesis; Carica papaya; Stomatal conductance; Leaf temperature. |
| Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452001000300014 |
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| Rakocevic, Miroslava; Medrado, Moacir José Sales; Lavoranti, Osmir José. |
| A preliminary study was developed on leaf gas exchange properties of males and females in yerbamate (Ilex paraguariensis St. Hil.), planted in open growth conditions. The photosynthesic photon flux density (PPFD) on leaf level, stomatal conductance (gs), net photosynthesis (A), transpiration (E), and leaf temperature (Tl) was measured during the biennial production period: in the summer during the fruit ripening when there is a pause in its growth (January, February), spring sprouting (November) and autumn sprouting (March, Jun). The measurements have been taken in different tree crown positions (inside, exterior and tips). First indications of sex physiological dimorphism in yerba-mate have been shown. Conductance was superior on female plants, with... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Light; Photosynthesis; Stomatal conductance; Temperature; Transpiration Condutância estomática; Fotossíntese; Luz; Temperatura; Transpiração. |
| Ano: 2010 |
URL: http://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/127 |
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| Registros recuperados: 35 | |
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