Artificial defoliation during budding stage in sunflower
Autor(a) principal: | |
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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/15357 |
Resumo: | In order to quantify reductions in leaf area which can be tolerated by sunflower plants (Helianthus annuus L.), an experiment was carried out at the Estação Experimental Agronômica of Universidade Federal do Rio Grande do Sul, in Guaíba, RS, Brazil, during the 1982/83 growing season. Plants were defoliated in two dates during the budding stage: when inflorescence head was visible, but tightly surrounded by young leaves, and when inflorescence began to open, with ray florets visible. In each of those dates eight defoliation levels were applied: removal of the leaves of the upper, medium and lower thirds of plant, individually; combination of these levels two by two; removal of all leaves, and an undefoliated check. There were no signiticant differences between defoliation dates for grain yield, grain weight, grain number in heads and head diameter. However, plant height, dry weight of stem plus head, and leaf area index varied with defoliation dates. Ali defoliation levels decreased grain yield in relation to check, with reductions varying from 16 to 100%, except for treatments where leaves were removed from the lower third of the plant and from the medium third. The levels of leaf removal affected statistically all characteristics evaluated. |
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Artificial defoliation during budding stage in sunflowerDesfolhamento artificial durante a formação do botão floral do girassolHelianthus annuus L.; Conti-GH 7811 cultivarHelianthus annuus L.; cultivar Conti-GH 7811In order to quantify reductions in leaf area which can be tolerated by sunflower plants (Helianthus annuus L.), an experiment was carried out at the Estação Experimental Agronômica of Universidade Federal do Rio Grande do Sul, in Guaíba, RS, Brazil, during the 1982/83 growing season. Plants were defoliated in two dates during the budding stage: when inflorescence head was visible, but tightly surrounded by young leaves, and when inflorescence began to open, with ray florets visible. In each of those dates eight defoliation levels were applied: removal of the leaves of the upper, medium and lower thirds of plant, individually; combination of these levels two by two; removal of all leaves, and an undefoliated check. There were no signiticant differences between defoliation dates for grain yield, grain weight, grain number in heads and head diameter. However, plant height, dry weight of stem plus head, and leaf area index varied with defoliation dates. Ali defoliation levels decreased grain yield in relation to check, with reductions varying from 16 to 100%, except for treatments where leaves were removed from the lower third of the plant and from the medium third. The levels of leaf removal affected statistically all characteristics evaluated.Com o objetivo de quantificar reduções da área foliar que as plantas de girassol (Helianthus annuus L.) podem tolerar, foi desenvolvido um trabalho na Estação Experimental Agronômica da UFRS, em Guaíba, RS, em 1982/83. As plantas foram desfolhadas em duas épocas durante o estádio de formação do botão floral, quando a inflorescência era visível, porém firmemente circundada por folhas jovens, e quando estavam começando a abrir as flores radiais. Em cada época, foram aplicados oito níveis de desfolhamento: remoção das folhas do terço superior, médio e inferior, individualmente; combinações dos terços, dois a dois; remoção de todas as folhas, e testemunha sem remoção de folhas. Não se observaram diferenças significativas entre épocas de desfolhamento para rendimento, peso de grãos, número de grãos por capítulo e diâmetro de capítulo. Entretanto, a estatura de plantas, peso seco de caule + capítulo e IAF mantido na planta variaram com a época de desfolhamento. Todos os níveis de desfolhamento reduziram o rendimento de grãos em relação à testemunha, com decréscimos variando de 16 a 100%, exceto os tratamentos com remoção das folhas do terço inferior e remoção das folhas do terço médio. Os níveis de remoção de folhas afetaram estatisticamente todas as características avaliadas.Pesquisa Agropecuaria BrasileiraPesquisa Agropecuária BrasileiraSilva, Paulo Regis F. daFleck, Nilson G.Heckler, João C.2014-04-16info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionapplication/pdfhttps://seer.sct.embrapa.br/index.php/pab/article/view/15357Pesquisa Agropecuaria Brasileira; v.19, n.2, fev. 1984; 149-156Pesquisa Agropecuária Brasileira; v.19, n.2, fev. 1984; 149-1561678-39210100-104xreponame:Pesquisa Agropecuária Brasileira (Online)instname:Empresa Brasileira de Pesquisa Agropecuária (Embrapa)instacron:EMBRAPAporhttps://seer.sct.embrapa.br/index.php/pab/article/view/15357/9230info:eu-repo/semantics/openAccess2014-04-16T19:16:05Zoai:ojs.seer.sct.embrapa.br:article/15357Revistahttp://seer.sct.embrapa.br/index.php/pabPRIhttps://old.scielo.br/oai/scielo-oai.phppab@sct.embrapa.br || sct.pab@embrapa.br1678-39210100-204Xopendoar:2014-04-16T19:16:05Pesquisa Agropecuária Brasileira (Online) - Empresa Brasileira de Pesquisa Agropecuária (Embrapa)false |
dc.title.none.fl_str_mv |
Artificial defoliation during budding stage in sunflower Desfolhamento artificial durante a formação do botão floral do girassol |
title |
Artificial defoliation during budding stage in sunflower |
spellingShingle |
Artificial defoliation during budding stage in sunflower Silva, Paulo Regis F. da Helianthus annuus L.; Conti-GH 7811 cultivar Helianthus annuus L.; cultivar Conti-GH 7811 |
title_short |
Artificial defoliation during budding stage in sunflower |
title_full |
Artificial defoliation during budding stage in sunflower |
title_fullStr |
Artificial defoliation during budding stage in sunflower |
title_full_unstemmed |
Artificial defoliation during budding stage in sunflower |
title_sort |
Artificial defoliation during budding stage in sunflower |
author |
Silva, Paulo Regis F. da |
author_facet |
Silva, Paulo Regis F. da Fleck, Nilson G. Heckler, João C. |
author_role |
author |
author2 |
Fleck, Nilson G. Heckler, João C. |
author2_role |
author author |
dc.contributor.none.fl_str_mv |
|
dc.contributor.author.fl_str_mv |
Silva, Paulo Regis F. da Fleck, Nilson G. Heckler, João C. |
dc.subject.por.fl_str_mv |
Helianthus annuus L.; Conti-GH 7811 cultivar Helianthus annuus L.; cultivar Conti-GH 7811 |
topic |
Helianthus annuus L.; Conti-GH 7811 cultivar Helianthus annuus L.; cultivar Conti-GH 7811 |
description |
In order to quantify reductions in leaf area which can be tolerated by sunflower plants (Helianthus annuus L.), an experiment was carried out at the Estação Experimental Agronômica of Universidade Federal do Rio Grande do Sul, in Guaíba, RS, Brazil, during the 1982/83 growing season. Plants were defoliated in two dates during the budding stage: when inflorescence head was visible, but tightly surrounded by young leaves, and when inflorescence began to open, with ray florets visible. In each of those dates eight defoliation levels were applied: removal of the leaves of the upper, medium and lower thirds of plant, individually; combination of these levels two by two; removal of all leaves, and an undefoliated check. There were no signiticant differences between defoliation dates for grain yield, grain weight, grain number in heads and head diameter. However, plant height, dry weight of stem plus head, and leaf area index varied with defoliation dates. Ali defoliation levels decreased grain yield in relation to check, with reductions varying from 16 to 100%, except for treatments where leaves were removed from the lower third of the plant and from the medium third. The levels of leaf removal affected statistically all characteristics evaluated. |
publishDate |
2014 |
dc.date.none.fl_str_mv |
2014-04-16 |
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/15357 |
url |
https://seer.sct.embrapa.br/index.php/pab/article/view/15357 |
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/15357/9230 |
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.19, n.2, fev. 1984; 149-156 Pesquisa Agropecuária Brasileira; v.19, n.2, fev. 1984; 149-156 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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1793416658982797312 |