Effects of postgrazing residue on morphogenetic and structural characteristics of Tifton 85 pastures
Autor(a) principal: | |
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Data de Publicação: | 2016 |
Outros Autores: | , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Semina. Ciências Agrárias (Online) |
Texto Completo: | https://ojs.uel.br/revistas/uel/index.php/semagrarias/article/view/18189 |
Resumo: | The ideal time to start grazing is when pastures reach 95% light interception. The use of residual leaf area index (rLAI) to time the interruption of grazing under intermittent grazing has recently been studied in forage species in different climatic conditions in Brazil. However, studies evaluating the formation and development of leaves and tillers through morphogenetic and structural variables in functional rLAI are still lacking for Tifton 85 pastures. Therefore, the objective of this study was to evaluate the effects of varying rLAI in successive grazing cycles on morphogenetic and structural characteristics of Tifton 85 pasture grazed intermittently by sheep. Morphogenetic and structural characteristics were evaluated in three grazing cycles under three rLAI conditions (0.8, 1.6, and 2.4). The regrowth interval (time taken to return to 95% light interception) of pastures increased from 21.33 to 29.66 days with decreasing rLAI. The leaf appearance rate increased at a rate of 0.02 leaves tiller-1 day-1 and the number of live leaves per tiller increased by 0.41 with decreasing rLAI. Phyllochron, leaf elongation rate, final leaf length, leaf senescence rate, and stem elongation rate decreased linearly with decreasing rLAI. The number of live leaves per tiller was lower (7.97) in the third grazing cycle, probably owing to the higher senescence rate observed that same cycle, while the other variables had higher values. The 2.4 rLAI condition promotes excessive stem elongation, reduced leaf appearance, lower number of live leaves per tiller, and increased senescence of leaves, while the 0.8 and 1.6 rLAI conditions promote desirable morphogenetic and structural characteristics, which correlate directly with forage quality. In order to avoid excessive forage losses, grazing must occur preferentially by the end of March, when climatic conditions still support the appropriate development of the plants. |
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Semina. Ciências Agrárias (Online) |
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Effects of postgrazing residue on morphogenetic and structural characteristics of Tifton 85 pasturesEfeitos de resíduos pós-pastejo sobre características morfogênicas e estruturais de pastos de Tifton 85Grazing cyclesLeaves appearanceLight interceptionResidual leaf area indexStem elongation.Forage EvaluationAlongamento do colmoAparecimento de folhasCiclos de pastejoÍndice de área foliar residualInterceptação de luz.Avaliação de ForragensThe ideal time to start grazing is when pastures reach 95% light interception. The use of residual leaf area index (rLAI) to time the interruption of grazing under intermittent grazing has recently been studied in forage species in different climatic conditions in Brazil. However, studies evaluating the formation and development of leaves and tillers through morphogenetic and structural variables in functional rLAI are still lacking for Tifton 85 pastures. Therefore, the objective of this study was to evaluate the effects of varying rLAI in successive grazing cycles on morphogenetic and structural characteristics of Tifton 85 pasture grazed intermittently by sheep. Morphogenetic and structural characteristics were evaluated in three grazing cycles under three rLAI conditions (0.8, 1.6, and 2.4). The regrowth interval (time taken to return to 95% light interception) of pastures increased from 21.33 to 29.66 days with decreasing rLAI. The leaf appearance rate increased at a rate of 0.02 leaves tiller-1 day-1 and the number of live leaves per tiller increased by 0.41 with decreasing rLAI. Phyllochron, leaf elongation rate, final leaf length, leaf senescence rate, and stem elongation rate decreased linearly with decreasing rLAI. The number of live leaves per tiller was lower (7.97) in the third grazing cycle, probably owing to the higher senescence rate observed that same cycle, while the other variables had higher values. The 2.4 rLAI condition promotes excessive stem elongation, reduced leaf appearance, lower number of live leaves per tiller, and increased senescence of leaves, while the 0.8 and 1.6 rLAI conditions promote desirable morphogenetic and structural characteristics, which correlate directly with forage quality. In order to avoid excessive forage losses, grazing must occur preferentially by the end of March, when climatic conditions still support the appropriate development of the plants.O momento de iniciar o pastejo quando os pastos atingem 95% de interceptação luminosa e de interrupção do pastejo por meio de índices de área foliar residual (IAFr), em situação de pastejo intermitente, recentemente vem sendo estudado em espécies forrageiras em distintas condições climáticas do Brasil, porém, pesquisas avaliando a formação e desenvolvimento de folhas e perfilhos por meio das variáveis morfogênicas e estruturais em função de IAFr são ainda inexistentes em pastos de Tifton 85. Por isso, objetivou-se com este trabalho, avaliar os efeitos de IAFr dos pastos, em ciclos de pastejos sucessivos, sobre as características morfogênicas e estruturais de Tifton 85 pastejados de maneira intermitente por ovinos. Características morfogênicas e estruturais dos pastos foram avaliadas em três ciclos de pastejo em função de três IAFr (0,8; 1,6 e 2,4). O intervalo de rebrotação dos pastos aumentou de 21,33 para 29,66 dias com a diminuição do IAFr. A taxa de aparecimento de folhas aumentou 0,02 folhas perfilho-1dia-1 e o número de folhas vivas por perfilho aumentou 0,41 com a diminuição do IAFr. Filocrono, taxa de alongamento de folhas, comprimento final de folha, taxa de senescência foliar e taxa de alongamento do colmo decresceram linearmente com a diminuição do IAFr dos pastos. Somente o número de folhas vivas por perfilho foi menor (7,97) no terceiro ciclo de pastejo, provavelmente pela maior taxa de senescência observada naquele mesmo ciclo enquanto as demais variáveis apresentaram maiores valores. O IAFr 2,4 promove alongamento excessivo de colmos, aparecimento reduzido de folhas, menor número de folhas vivas por perfilho e maior senescência de folhas, enquanto os IAFr 0,8 e 1,6 promovem características morfogênicas e estruturais desejáveis, as quais se correlacionam diretamente á qualidade da forragem. Para evitar perdas excessivas de forragem, o pastejo deve ocorrer, preferencialmente, até final do mês de março, onde as condições climáticas ainda favorecem o adequado desenvolvimento das plantas.UEL2016-08-30info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionEmpirical ResearchPesquisa Empíricaapplication/pdfhttps://ojs.uel.br/revistas/uel/index.php/semagrarias/article/view/1818910.5433/1679-0359.2016v37n4p2043Semina: Ciências Agrárias; Vol. 37 No. 4 (2016); 2043-2052Semina: Ciências Agrárias; v. 37 n. 4 (2016); 2043-20521679-03591676-546Xreponame:Semina. Ciências Agrárias (Online)instname:Universidade Estadual de Londrina (UEL)instacron:UELenghttps://ojs.uel.br/revistas/uel/index.php/semagrarias/article/view/18189/19449http://creativecommons.org/licenses/by-nc/4.0info:eu-repo/semantics/openAccessSilva, Wilton LadeiraRuggieri, Ana CláudiaReis, Ricardo AndradeSilva Sobrinho, Américo GarciaMalheiros, Euclides Braga2022-11-30T16:54:06Zoai:ojs.pkp.sfu.ca:article/18189Revistahttp://www.uel.br/revistas/uel/index.php/semagrariasPUBhttps://ojs.uel.br/revistas/uel/index.php/semagrarias/oaisemina.agrarias@uel.br1679-03591676-546Xopendoar:2022-11-30T16:54:06Semina. Ciências Agrárias (Online) - Universidade Estadual de Londrina (UEL)false |
dc.title.none.fl_str_mv |
Effects of postgrazing residue on morphogenetic and structural characteristics of Tifton 85 pastures Efeitos de resíduos pós-pastejo sobre características morfogênicas e estruturais de pastos de Tifton 85 |
title |
Effects of postgrazing residue on morphogenetic and structural characteristics of Tifton 85 pastures |
spellingShingle |
Effects of postgrazing residue on morphogenetic and structural characteristics of Tifton 85 pastures Silva, Wilton Ladeira Grazing cycles Leaves appearance Light interception Residual leaf area index Stem elongation. Forage Evaluation Alongamento do colmo Aparecimento de folhas Ciclos de pastejo Índice de área foliar residual Interceptação de luz. Avaliação de Forragens |
title_short |
Effects of postgrazing residue on morphogenetic and structural characteristics of Tifton 85 pastures |
title_full |
Effects of postgrazing residue on morphogenetic and structural characteristics of Tifton 85 pastures |
title_fullStr |
Effects of postgrazing residue on morphogenetic and structural characteristics of Tifton 85 pastures |
title_full_unstemmed |
Effects of postgrazing residue on morphogenetic and structural characteristics of Tifton 85 pastures |
title_sort |
Effects of postgrazing residue on morphogenetic and structural characteristics of Tifton 85 pastures |
author |
Silva, Wilton Ladeira |
author_facet |
Silva, Wilton Ladeira Ruggieri, Ana Cláudia Reis, Ricardo Andrade Silva Sobrinho, Américo Garcia Malheiros, Euclides Braga |
author_role |
author |
author2 |
Ruggieri, Ana Cláudia Reis, Ricardo Andrade Silva Sobrinho, Américo Garcia Malheiros, Euclides Braga |
author2_role |
author author author author |
dc.contributor.author.fl_str_mv |
Silva, Wilton Ladeira Ruggieri, Ana Cláudia Reis, Ricardo Andrade Silva Sobrinho, Américo Garcia Malheiros, Euclides Braga |
dc.subject.por.fl_str_mv |
Grazing cycles Leaves appearance Light interception Residual leaf area index Stem elongation. Forage Evaluation Alongamento do colmo Aparecimento de folhas Ciclos de pastejo Índice de área foliar residual Interceptação de luz. Avaliação de Forragens |
topic |
Grazing cycles Leaves appearance Light interception Residual leaf area index Stem elongation. Forage Evaluation Alongamento do colmo Aparecimento de folhas Ciclos de pastejo Índice de área foliar residual Interceptação de luz. Avaliação de Forragens |
description |
The ideal time to start grazing is when pastures reach 95% light interception. The use of residual leaf area index (rLAI) to time the interruption of grazing under intermittent grazing has recently been studied in forage species in different climatic conditions in Brazil. However, studies evaluating the formation and development of leaves and tillers through morphogenetic and structural variables in functional rLAI are still lacking for Tifton 85 pastures. Therefore, the objective of this study was to evaluate the effects of varying rLAI in successive grazing cycles on morphogenetic and structural characteristics of Tifton 85 pasture grazed intermittently by sheep. Morphogenetic and structural characteristics were evaluated in three grazing cycles under three rLAI conditions (0.8, 1.6, and 2.4). The regrowth interval (time taken to return to 95% light interception) of pastures increased from 21.33 to 29.66 days with decreasing rLAI. The leaf appearance rate increased at a rate of 0.02 leaves tiller-1 day-1 and the number of live leaves per tiller increased by 0.41 with decreasing rLAI. Phyllochron, leaf elongation rate, final leaf length, leaf senescence rate, and stem elongation rate decreased linearly with decreasing rLAI. The number of live leaves per tiller was lower (7.97) in the third grazing cycle, probably owing to the higher senescence rate observed that same cycle, while the other variables had higher values. The 2.4 rLAI condition promotes excessive stem elongation, reduced leaf appearance, lower number of live leaves per tiller, and increased senescence of leaves, while the 0.8 and 1.6 rLAI conditions promote desirable morphogenetic and structural characteristics, which correlate directly with forage quality. In order to avoid excessive forage losses, grazing must occur preferentially by the end of March, when climatic conditions still support the appropriate development of the plants. |
publishDate |
2016 |
dc.date.none.fl_str_mv |
2016-08-30 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Empirical Research Pesquisa Empírica |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
https://ojs.uel.br/revistas/uel/index.php/semagrarias/article/view/18189 10.5433/1679-0359.2016v37n4p2043 |
url |
https://ojs.uel.br/revistas/uel/index.php/semagrarias/article/view/18189 |
identifier_str_mv |
10.5433/1679-0359.2016v37n4p2043 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
https://ojs.uel.br/revistas/uel/index.php/semagrarias/article/view/18189/19449 |
dc.rights.driver.fl_str_mv |
http://creativecommons.org/licenses/by-nc/4.0 info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
http://creativecommons.org/licenses/by-nc/4.0 |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
UEL |
publisher.none.fl_str_mv |
UEL |
dc.source.none.fl_str_mv |
Semina: Ciências Agrárias; Vol. 37 No. 4 (2016); 2043-2052 Semina: Ciências Agrárias; v. 37 n. 4 (2016); 2043-2052 1679-0359 1676-546X reponame:Semina. Ciências Agrárias (Online) instname:Universidade Estadual de Londrina (UEL) instacron:UEL |
instname_str |
Universidade Estadual de Londrina (UEL) |
instacron_str |
UEL |
institution |
UEL |
reponame_str |
Semina. Ciências Agrárias (Online) |
collection |
Semina. Ciências Agrárias (Online) |
repository.name.fl_str_mv |
Semina. Ciências Agrárias (Online) - Universidade Estadual de Londrina (UEL) |
repository.mail.fl_str_mv |
semina.agrarias@uel.br |
_version_ |
1799306072141332480 |