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| Barreto,Denize Caranhas de Sousa; Gonçalves,José Francisco de Carvalho; Santos Júnior,Ulysses Moreira dos; Fernandes,Andreia Varmes; Bariani,Adriana; Sampaio,Paulo de Tarso Barbosa. |
| The rosewood (Aniba rosaeodora Ducke) is a native tree species of Amazon rainforest growing naturally in acidic forest soils with reduced redox potential. However, this species can also been found growing in forest gaps containing oxide soils. Variations in the forms of mineral nitrogen (NO3- or NH4+) may be predicted in these different edaphic conditions. Considering that possibility, an experiment was carried out to analyze the effects of different NO3-:NH4+ ratios on the growth performance, mineral composition, chloroplastid pigment contents, photochemical efficiency photosystem II (PSII), and nitrate redutase activity (RN, E.C.1.6.6.1) on A. rosaeodora seedlings. Nine-month-old seedlings were grown in pots with a washed sand capacity of 7.5 kg and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chloroplastid pigments; Chlorophyll a fluorescence; Tree species. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672007000400008 |
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| Gonçalves,José Francisco de Carvalho; Santos Júnior,Ulysses Moreira dos. |
| We examine the hypothesis that the chlorophyll a fluorescence technique can be an efficient tool to support the selection of species adapted to high irradiance and therefore, suitable for use in initial rehabilitation projects of degraded areas. The experiment was conducted at the Pedro de Moura Operational Base, Amazonas, Brazil. The fluorescence transients were obtained using a portable fluorometer for leaves of Bombacopsis macrocalyx (Bm), Eugenia cumini (Ec), Iryanthera macrophyla (Im) and Senna reticulata (Sr), which were subjected to high irradiance between 12:00 am and 1:00 p.m. Using the OJIP test, the following were calculated: performance index (PI ABS), density of reaction centres per cross section (RC/CS), maximum efficiency of photosystem II... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Degraded areas; Energy flux; Performance index. |
| Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202005000300005 |
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| Gonçalves,José Francisco de Carvalho; Santos Júnior,Ulysses Moreira dos; Silva,José Ferreira da; Arruda,Murilo Rodrigues de; Bonates,Luiz Carlos de Matos; Fernandes,Andreia Varmes. |
| The objective of this work was to analyze gas exchange, photosynthetic characteristics, photochemical efficiency of photosystem II and anatomical characteristics of young plant leaves of two guarana (Paullinia cupana) clones (BRS-CG372RC and BRS-CG611RL) growing under open field. The variables of gas exchange and fluorescence of chlorophyll a were evaluated in mature leaves. The values of photosynthesis and transpiration found for BRS-CG372RC were 27% greater and 80% lesser than values found for BRS-CG611RL, respectively. The values of stomatal conductance found for the clones BRS-CG372RC and BRS-CG611RL were in the order of 224 and 614 mmol mm-2 s-1, respectively. The values of photorespiration, rate of carboxylation and rate electron transport were... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Paullinia cupana; Photosynthesis; Photochemical efficiency of photosystem II; Electron transport rate; Water use efficiency; Stomatal anatomy. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2006000300004 |
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