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Lima,Ana Lúcia da Silva; Zanella,Fábio; Schiavianto,Marlene Aparecida; Haddad,Claudia Regina Baptista. |
Prior to abscission, nutrients are redeployed from leaves and redistributed to other parts of the plant. Data comparing nutrient resorption to soil fertility and leaf life span remains controversial in the literature. We compared nitrogen (N) conservation mechanisms among four legume trees with different leaf life spans (Hymenaea courbaril L. var. stilbocarpa (Hayne) Lee et Lang., Lonchocarpus guilleminianus (Tul.) Malme, Enterolobium contortisiliquum (Vell.) Morong and Peltophorum dubium (Spreng.) Taub.), from a semideciduous tropical forest, remnant of the Atlantic Forest. We hypothesized that these mechanisms differ among the four species and are affected by their leaf life span and by the availability of N, both as a mineral in the soil and, in the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Leaf life span; Nitrogen fixation; Nitrogen resorption efficiency; Nitrogen resorption proficiency; Nitrogen-use efficiency. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062006000300012 |
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Zanella,Fábio; Watanabe,Tania Misae; Lima,Ana Lúcia da Silva; Schiavinato,Marlene Aparecida. |
The effects of drought and rehydration on Canavalia ensiformis (L.) D.C. (jack bean) plants were evaluated using the following gas exchange parameters: net carbon assimilation rate (A), stomatal conductance (g s), Ci/Ca ratio and transpiration rate (E); chlorophyll a fluorescence: Fv/Fm and Fv/F0 ratio. The plants were cultivated under greenhouse conditions and after 30 days from the emergence, irrigation was suspended in the plants submitted to drought, to obtain the following predawn leaf water potential (psipd): -0.40 MPa (control), -1.00 MPa (moderate drought) and -2.30 Mpa (severe drought). Afterwards, the gas exchange and fluorescence analysis were initiated , and 24 h after rehydration the same analyses were repeated. The A, E, g s and Ci/Ca values... |
Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Fluorescence; Moderate drought; Photosynthesis; Severe drought; Stomatal conductance. |
Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202004000300008 |
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Carvalho,Jimmy Elizio de; Zanella,Fabio; Mota,José Hortêncio; Lima,Ana Lúcia da Silva. |
Conduziu-se este estudo com o objetivo de avaliar o efeito de diferentes materiais de cobertura do solo na produtividade da alface (Lactuca sativa L. cv. Regina 2000). O delineamento experimental utilizado foi o de blocos casualizados, utilizando-se cinco tratamentos (palha de arroz, palha de café, Brachiaria brizantha L., serragem, testemunha sem cobertura morta) e quatro repetições. A produtividade foi avaliada pelo número de folhas por planta, acúmulo de massa fresca e massa seca. Verificou-se que todos os materiais empregados como cobertura, controlaram a infestação de plantas invasoras. Entretanto, verificou-se uma grande infestação na testemunha promovendo redução de produtividade. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Lactuca sativa; Cobertura morta; Plantas invasoras. |
Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542005000500003 |
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Lima,Ana Lúcia da Silva; Zanella,Fábio; Schiavinato,Marlene Aparecida; Haddad,Claudia Regina Baptista. |
In general, perennial species contain higher concentrations of certain secondary compounds, such as phenolics, lower levels of nitrogenous compounds, and greater specific leaf mass (SLM) than deciduous species. The aim of this study was to verify whether the comparative data reported in the literature regarding deciduous and evergreen species, also applies to four selected species of a semideciduous tropical forest (a remnant of the Atlantic Forest). The four species chosen for this study, each with apparently different leaf life spans, were two semideciduous (Hymenaea courbaril L. var. stilbocarpa (Hayne) Lee et Lang., and Lonchocarpus guilleminianus (Tul.) Malme, and two deciduous (Enterolobium contortisiliquum (Vell.) Morong., and Peltophorum dubium... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Leaf life span; Specific leaf mass; Total nitrogen; Tannins; Atlantic forest. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162006000100007 |
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