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| Registros recuperados: 45 | |
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| PEREZ MARTINEZ,Laura Victoria; MELGAREJO,Luz Marina. |
| Gulupa, Passiflora edulis Sims (Passifloraceae), is an important fruit due to its organoleptic and nutritional characteristics and its demand in the international market; however, very few studies have been conducted for studying its Ecophysiology. Until now, this crop has spread throughout the country through empirical knowledge without data that indicate the zones that are more suitable for its cultivation. For this reason, gas exchange, chlorophyll fluorescence (photosystem II operating efficiency and maximum quantum efficiency of photosystem II photochemistry) and leaf water potential were measured in three different locations of Cundinamarca department (Chia [2610 m a.s.l., 14 °C], Granada [2230 m a.s.l., 15 °C] and Tena [2090 m a.s.l., 17 °C]), whose... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chlorophyll fluorescence; Crop; Horticulture; Passion fruit; Photosynthesis; Plant physiology; Water. |
| Ano: 2015 |
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-548X2015000100019 |
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| JAIMEZ,Ramon Eduardo; AMORES PUYUTAXI,Freddy; VASCO,Alfonso; Gastón LOOR,Rey; TARQUI,Omar; QUIJANO,Grisnel; JIMENEZ,Juan Carlos; TEZARA,Wilmer. |
| ABSTRACT Cacao (Theobroma cacao L.) breeding programmes in Ecuador have focused on obtaining high-yield clones with improved disease resistance. Cacao clones should also have photosynthetic characteristics which support increased productivity. Regarding the weather conditions at the coast of Ecuador, where most of the year there are overcasts and low air evaporative demand, there is the possibility to grow cacao without overhead shade. This study focused on the photosynthetic response at two different photosynthetic photon flux densities (PPFD) of Ecuadorian cacao clones. Seven-year old cacao clones were evaluated: eight clones of Nacional type and two commercial clones (CCN 51 and EET 103), used as controls. All clones showed an increase of 35 % on... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cacao yield; Chlorophyll fluorescence; CO2 assimilation rate; Gas exchange. |
| Ano: 2018 |
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-548X2018000100095 |
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| Hampp,Rüdiger; Cardoso,Nelsa; Fleig,Mariana; Grüninger,Werner. |
| ABSTRACT The vitality of 64 lichen species (107 individual lichen thalli) growing under different light climates in an Araucaria forest in South Brazil was analyzed by chlorophyll fluorescence. Study sites were grouped according to their local light availability under full sunlight (about 2200 µmol m-2 s-1): 1 = low light, up to 20 µmol m-2 s-1; 2 = medium light, 20 to 100 µmol m-2 s-1; and 3 = high light, more than 100 µmol m-2 s-1. Maximum quantum yield of photosystem II, as shown by Fv/Fm of dark-adapted samples, was mainly between 0.3 and 0.7, with extremes of below 0.1 and up to 0.85. On average, yields were highest with low light availability (0.66). Groups 1 and 2 were not significantly different from each other, but groups 1 and 3, as well as... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Araucaria forest; Chlorophyll fluorescence; Heat dissipation; Lichens; PAM fluorometer; Photosynthetic yield. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062018000200188 |
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| Frosi,Gabriella; Harand,Wolfgang; Oliveira,Marciel Teixeira de; Pereira,Silvia; Cabral,Simone Pereira; Montenegro,Abelardo Antônio de Assunção; Santos,Mauro Guida. |
| ABSTRACT The effects of water deficit on physiological and biochemical variables of young plants of two tropical woody species, Pachira aquatica and Sterculia foetida, and their recovery abilities were measured. Leaf water potential, gas exchange and selected carbon metabolism components were measured in a greenhouse experiment with control, moderate and severe water deficit treatments. Under severe drought stress, gas exchange and chlorophyll fluorescence decreased in both species compared to their respective controls. After rehydration, P. aquatica and S. foetida showed a partial and full recovery of the measured variables, respectively. In addition, a decrease and an increase in photosynthetic pigments were observed for P. aquatica and S. foetida,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chlorophyll fluorescence; Climate changes; Gas exchange; Semiarid; Water deficit. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062017000200153 |
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| Ribeiro,Rafael Vasconcelos; Santos,Mauro Guida dos; Pimentel,Carlos; Machado,Eduardo Caruso; Oliveira,Ricardo Ferraz de. |
| Low water availability and high temperatures occur under field conditions and we hypothesize that the critical temperature for photochemical damage (TC) in common bean (Phaseolus vulgaris L.) plants is increased by the occurrence of previous water deficit in a genotype-dependent manner. Five common bean cultivars A320, A222, Carioca, BAT477 and Ouro Negro were evaluated. Thirty days after seedlings emergence, one group of plants was exposed to water deficit for ten days and rehydrated and another one was maintained well hydrated during the experimental period. The minimum chlorophyll fluorescence (FO) was monitored in leaf discs exposed to temperatures ranging from 25 to 45 oC and the TC values estimated. The previous water deficit did not affect TC, which... |
| Tipo: Info:eu-repo/semantics/report |
Palavras-chave: Chlorophyll fluorescence; Hardening; Heat stress; Phaseolus vulgaris; Tolerance. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052015000400374 |
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| Bautista,Anna I.N.; Necchi Jr.,Orlando. |
| Three freshwater Rhodophyta species (Audouinella eugenea, A. hermannii and Compsopogon coeruleus) were tested as to their responses (photosynthesis, growth and pigment concentration) to two irradiances (low light, LL, 65 µmol m-2 s-1 and high light, HL, 300 µmol m-2 s-1) and two periods (short time, ST, 4 d, and long time, LT, 28 d). Higher growth rates were consistently observed at LL but significant differences were observed only for A. hermannii. Higher values of photoinhibition at LL were found for the three species, which is consistent with the dynamic photoinhibition as a reversible photoprotective mechanism against high irradiance. Light-induced decreases of effective quantum yield (EQY) were observed in the three species consisting of pronounced... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chlorophyll fluorescence; Growth; Irradiance; Photosynthesis; Pigment; Red algae. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000100003 |
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| Mengarda,Liana H. G.; Souza,Rogério L. F. de; Campostrini,Eliemar; Reis,Fabrício O.; Vendrame,Wagner A.; Cuzzuol,Geraldo R. F.. |
| The ecophysiological behavior of brazilwood (Caesalpinia echinata Lam.) plants was evaluated as affected by light quantity and quality. Nine-month-old plants were cultivated under 0%, 50%, and 80% artificial shading, and natural shading imposed by a closed canopy for a period of 392 days. At the end of that period growth parameters were measured, including relative growth rate (RGR), net assimilation rate (NAR), leaf area ratio (LAR), specific leaf mass (SLM) and root:shoot ratio (R:S). Higher leaf area, dry mass and RGR were obtained under 50% artificial shade. Under full sunlight (0% shade), growth was satisfactory showing higher R:S and SLM. Growth was inhibited under 80% artificial and natural shading indicating that C. echinata is not... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chlorophyll fluorescence; Gas exchange; Growth; Light stress; Shade; Tropical tree. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202009000100007 |
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| Miguel,Aurélio Antas; Oliveira,Luiz Edson Mota de; Cairo,Paulo Araquém Ramos; Oliveira,Davi Melo de. |
| This work proposed to investigate changes in the photosynthetic behavior during the leaf ontogeny of the during the leaf development. Up to the 32nd day of leaf age (stage B2), the net photosynthesis was negative due to the inefficiency of the photosynthetic system, and this fact was justified by the following factors: low chlorophyll content, less stomatal conductance, high rubber tree clones PB 235, RRIM 600 and GT 1, in Lavras, MG. The experiment was performed in 2004, between May and July, under field conditions, at the Universidade Federal de Lavras. During the leaf ontogeny, the following characteristics were evaluated: chlorophyll content, gaseous exchanges and chlorophyll fluorescence. The clones presented similar profiles of alterations in the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Rubber tree; Photosynthesis; Gaseous exchanges; Chlorophyll fluorescence. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542007000100014 |
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| Bown,Horacio E; Mason,Euan G; Clinton,Peter W; Watt,Michael S. |
| Chlorophyll fluorescence responses to a factorial combination of nitrogen (N) and phosphorus (P) supply were measured in five clones of Pinus radiata cultivated in a greenhouse over twenty-four months. Chlorophyll fluorescence measurements were taken at months six (5 clones, 182 plants), nine (2 clones, 68 plants) and eighteen (2 clones, 48 plants). Plant growth in stem diameter, height, leaf area, fascicle mass, length and diameter were found to significantly increase with N and, to a lesser extent, P additions; and these values were greatest when both N and P were combined. Plant growth and fascicle size also varied significantly across clones and were generally consistent with the genotypic growth responses that were observed in the field. Dark (Fv /... |
| Tipo: Journal article |
Palavras-chave: Chlorophyll fluorescence; Quantum efficiency of PSII; Electron transport; Genotype; Nutrient limitation. |
| Ano: 2009 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202009000300012 |
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| Deus,Bruna Corrêa da Silva de; Figueiredo,Fábio Afonso Mazzei Moura de Assis; Almeida,Luciana Venturotti Braun de; Ferraz,Tiago Massi; Martins,Amanda Oliveira; Rodrigues,Weverton Pereira; Viana,Leandro Hespanhol; Esteves,Barbara dos Santos; Campostrini,Eliemar. |
| ABSTRACT: New techniques in tropical regions such as use of transparent plastic covering (TPC), have been employed in grapes to avoid the wetting leaves and fruits, which can reduce the occurrence of fungal diseases, reduce the use of sprays, and reduce damage caused by hail and high winds. TPC may significantly affect the photosynthetic rates of grapevines cultivated in tropical regions, and thus have strong effects on plant productivity and improve fruit quality. However, in the North of Rio de Janeiro region there are lacks of studies related to TPC effects on photosynthetic capacity. The objective of this study was to evaluate the photosynthetic capacity in 'Niagara Rosada' vines grown under TPC and without transparent plastic covering (WTPC). The... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Photosynthesis; Chlorophyll fluorescence; Vitisla brusca; Covered system. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782016000600950 |
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| Registros recuperados: 45 | |
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