Leaf area index and yield of upland rice. I. Limiting levels
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Data de Publicação: | 2014 |
Outros Autores: | |
Tipo de documento: | Artigo |
Idioma: | por |
Título da fonte: | Pesquisa Agropecuária Brasileira (Online) |
Texto Completo: | https://seer.sct.embrapa.br/index.php/pab/article/view/13511 |
Resumo: | The relationship between leaf area index (LAI) and yield of upland rice was studied in 12 field experiments during five years, using IAC 47, a medium growth duration cultivar. There was great growth variation among experiments, with maximum LAI Ranging between 1.5 and 8.3, and leaf area duration (LAD) during reproductive stage ranging between 49 and 339 days. In the absence of environmental stresses, yield increased with LAI up to the level of 4,000 kg/ha at a LAI of 4.5. LAI levels below 2.0 minimized the risk of yield losses due to water stress, but yield potential was restricted to 1,500 kg/ha. Yield losses due to water stress during the reproductive stage were higher than 40% when LAI was higher than 3.0. LAI values higher than 6.0, associated with high rainfail and nebulosity during the reproductive stage, resulted in yields below 2,500 kg/ha. The possibility of using LAI as a factor of increase of mean upland rice yield in regions of both risky and favorable rainfail distribution is discussed. |
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Leaf area index and yield of upland rice. I. Limiting levelsÍndice de área foliar e produtividade do arroz de sequeiro. I. Níveis limitantesleaf area duration (LAD); yield potential; critical LAI; water stress.duração da área foliar (DAF); potencial produtivo; IAF crítico; deficiência hídrica.The relationship between leaf area index (LAI) and yield of upland rice was studied in 12 field experiments during five years, using IAC 47, a medium growth duration cultivar. There was great growth variation among experiments, with maximum LAI Ranging between 1.5 and 8.3, and leaf area duration (LAD) during reproductive stage ranging between 49 and 339 days. In the absence of environmental stresses, yield increased with LAI up to the level of 4,000 kg/ha at a LAI of 4.5. LAI levels below 2.0 minimized the risk of yield losses due to water stress, but yield potential was restricted to 1,500 kg/ha. Yield losses due to water stress during the reproductive stage were higher than 40% when LAI was higher than 3.0. LAI values higher than 6.0, associated with high rainfail and nebulosity during the reproductive stage, resulted in yields below 2,500 kg/ha. The possibility of using LAI as a factor of increase of mean upland rice yield in regions of both risky and favorable rainfail distribution is discussed.Foi estudada a relação entre o índice de área foliar (IAF) e a produtividade do arroz de sequeiro, durante cinco anos, em doze experimentos de campo, utilizando-se a cultivar de ciclo médio IAC 47. houve grande variação no crescimento da cultivar, tendo o máximo IAF variado de 1,5 a 8,3 e a duração da área foliar no período reprodutivo (DAFr) variado de 49 a 339 dias. Na ausência de estresses ambientais a produtividade cresceu com o IAF até o valor de 4,5, quando foi atingido um patamar em torno de 4.000 kg/ha. Valores de IAF inferiores a 2,0, apesar de minimizarem o risco de perda por deficiência hídrica, restringiram o potencial produtivo a 1.500 kg/ha. Quando o IAF foi superior a 3,0, a deficiência hídrica no período reprodutivo resultou em quebras de rendimento superiores a 40%. Quando valores de IAF superiores a 6,0 ocorreram, associados à alta pluviosidade e a dias encobertos no período reprodutivo, as produtividades foram inferiores a 2.500 kg/ha. São discutidas as implicações desses resultados e a possibilidade de utilização do IAF no aumento da produtividade média do arroz de sequeiro em regiões de alto risco de estiagens e em regiões favorecidas quanto à distribuição pluvialPesquisa Agropecuaria BrasileiraPesquisa Agropecuária BrasileiraPinheiro, Beatriz da SilveiraGuimarães, Elcio Perpétuo2014-04-17info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionapplication/pdfhttps://seer.sct.embrapa.br/index.php/pab/article/view/13511Pesquisa Agropecuaria Brasileira; v.25, n.6, jun. 1990; 863-872Pesquisa Agropecuária Brasileira; v.25, n.6, jun. 1990; 863-8721678-39210100-104xreponame:Pesquisa Agropecuária Brasileira (Online)instname:Empresa Brasileira de Pesquisa Agropecuária (Embrapa)instacron:EMBRAPAporhttps://seer.sct.embrapa.br/index.php/pab/article/view/13511/7675info:eu-repo/semantics/openAccess2014-04-17T14:34:39Zoai:ojs.seer.sct.embrapa.br:article/13511Revistahttp://seer.sct.embrapa.br/index.php/pabPRIhttps://old.scielo.br/oai/scielo-oai.phppab@sct.embrapa.br || sct.pab@embrapa.br1678-39210100-204Xopendoar:2014-04-17T14:34:39Pesquisa Agropecuária Brasileira (Online) - Empresa Brasileira de Pesquisa Agropecuária (Embrapa)false |
dc.title.none.fl_str_mv |
Leaf area index and yield of upland rice. I. Limiting levels Índice de área foliar e produtividade do arroz de sequeiro. I. Níveis limitantes |
title |
Leaf area index and yield of upland rice. I. Limiting levels |
spellingShingle |
Leaf area index and yield of upland rice. I. Limiting levels Pinheiro, Beatriz da Silveira leaf area duration (LAD); yield potential; critical LAI; water stress. duração da área foliar (DAF); potencial produtivo; IAF crítico; deficiência hídrica. |
title_short |
Leaf area index and yield of upland rice. I. Limiting levels |
title_full |
Leaf area index and yield of upland rice. I. Limiting levels |
title_fullStr |
Leaf area index and yield of upland rice. I. Limiting levels |
title_full_unstemmed |
Leaf area index and yield of upland rice. I. Limiting levels |
title_sort |
Leaf area index and yield of upland rice. I. Limiting levels |
author |
Pinheiro, Beatriz da Silveira |
author_facet |
Pinheiro, Beatriz da Silveira Guimarães, Elcio Perpétuo |
author_role |
author |
author2 |
Guimarães, Elcio Perpétuo |
author2_role |
author |
dc.contributor.none.fl_str_mv |
|
dc.contributor.author.fl_str_mv |
Pinheiro, Beatriz da Silveira Guimarães, Elcio Perpétuo |
dc.subject.por.fl_str_mv |
leaf area duration (LAD); yield potential; critical LAI; water stress. duração da área foliar (DAF); potencial produtivo; IAF crítico; deficiência hídrica. |
topic |
leaf area duration (LAD); yield potential; critical LAI; water stress. duração da área foliar (DAF); potencial produtivo; IAF crítico; deficiência hídrica. |
description |
The relationship between leaf area index (LAI) and yield of upland rice was studied in 12 field experiments during five years, using IAC 47, a medium growth duration cultivar. There was great growth variation among experiments, with maximum LAI Ranging between 1.5 and 8.3, and leaf area duration (LAD) during reproductive stage ranging between 49 and 339 days. In the absence of environmental stresses, yield increased with LAI up to the level of 4,000 kg/ha at a LAI of 4.5. LAI levels below 2.0 minimized the risk of yield losses due to water stress, but yield potential was restricted to 1,500 kg/ha. Yield losses due to water stress during the reproductive stage were higher than 40% when LAI was higher than 3.0. LAI values higher than 6.0, associated with high rainfail and nebulosity during the reproductive stage, resulted in yields below 2,500 kg/ha. The possibility of using LAI as a factor of increase of mean upland rice yield in regions of both risky and favorable rainfail distribution is discussed. |
publishDate |
2014 |
dc.date.none.fl_str_mv |
2014-04-17 |
dc.type.none.fl_str_mv |
|
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
https://seer.sct.embrapa.br/index.php/pab/article/view/13511 |
url |
https://seer.sct.embrapa.br/index.php/pab/article/view/13511 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.relation.none.fl_str_mv |
https://seer.sct.embrapa.br/index.php/pab/article/view/13511/7675 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Pesquisa Agropecuaria Brasileira Pesquisa Agropecuária Brasileira |
publisher.none.fl_str_mv |
Pesquisa Agropecuaria Brasileira Pesquisa Agropecuária Brasileira |
dc.source.none.fl_str_mv |
Pesquisa Agropecuaria Brasileira; v.25, n.6, jun. 1990; 863-872 Pesquisa Agropecuária Brasileira; v.25, n.6, jun. 1990; 863-872 1678-3921 0100-104x reponame:Pesquisa Agropecuária Brasileira (Online) instname:Empresa Brasileira de Pesquisa Agropecuária (Embrapa) instacron:EMBRAPA |
instname_str |
Empresa Brasileira de Pesquisa Agropecuária (Embrapa) |
instacron_str |
EMBRAPA |
institution |
EMBRAPA |
reponame_str |
Pesquisa Agropecuária Brasileira (Online) |
collection |
Pesquisa Agropecuária Brasileira (Online) |
repository.name.fl_str_mv |
Pesquisa Agropecuária Brasileira (Online) - Empresa Brasileira de Pesquisa Agropecuária (Embrapa) |
repository.mail.fl_str_mv |
pab@sct.embrapa.br || sct.pab@embrapa.br |
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1793416715142430720 |