Tiller size/population density compensation in grazed Coastcross bermudagrass swards
Autor(a) principal: | |
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Data de Publicação: | 2001 |
Outros Autores: | , , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Scientia Agrícola (Online) |
Texto Completo: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162001000400002 |
Resumo: | Several compensatory mechanisms in pastures do not allow optimisation of responses from the processes of herbage production and utilisation. Compensation due to tiller size/density relationships is one of these mechanisms. This experiment evaluated this process for Coastcross bermudagrass and compared the responses to those reported for temperate forages. Treatments were "steady state" sward surface heights of 5, 10, 15, and 20 cm that were maintained from August, 1998, through July, 1999 by sheep grazing. The experimental design was a randomised complete block, replicated four times. Pasture responses were evaluated on four separate dates (15/12/1998, 25/01/1999, 07/04/1999 and 04/07/1999) with respect to: tiller population density, tiller weight, leaf mass and leaf area per tiller and herbage mass (biomass). Tiller volume, leaf area index (LAI), tiller leaf:stem ratio and tiller leaf area:volume ratio (R) were calculated. Simple regression analyses between tiller population density and tiller weight were also performed. Coastcross swards showed a tiller size/density compensation mechanism where high tiller population densities were associated with small tillers and vice-versa; except on the last evaluation. However, regression analysis revealed linear coefficients of -3.83 to -2.05, which are lower than the theoretical expectation of -3/2. The lower R values observed, when compared to those reported for perennial ryegrass, suggest that Coastcross swards optimised their LAI via clonal integration among tillers in contrast with tillers of cool-season grasses that respond more as individuals. However, this hypothesis has yet to be experimentally verified. |
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Tiller size/population density compensation in grazed Coastcross bermudagrass swardsCynodonLAItillermorphologySeveral compensatory mechanisms in pastures do not allow optimisation of responses from the processes of herbage production and utilisation. Compensation due to tiller size/density relationships is one of these mechanisms. This experiment evaluated this process for Coastcross bermudagrass and compared the responses to those reported for temperate forages. Treatments were "steady state" sward surface heights of 5, 10, 15, and 20 cm that were maintained from August, 1998, through July, 1999 by sheep grazing. The experimental design was a randomised complete block, replicated four times. Pasture responses were evaluated on four separate dates (15/12/1998, 25/01/1999, 07/04/1999 and 04/07/1999) with respect to: tiller population density, tiller weight, leaf mass and leaf area per tiller and herbage mass (biomass). Tiller volume, leaf area index (LAI), tiller leaf:stem ratio and tiller leaf area:volume ratio (R) were calculated. Simple regression analyses between tiller population density and tiller weight were also performed. Coastcross swards showed a tiller size/density compensation mechanism where high tiller population densities were associated with small tillers and vice-versa; except on the last evaluation. However, regression analysis revealed linear coefficients of -3.83 to -2.05, which are lower than the theoretical expectation of -3/2. The lower R values observed, when compared to those reported for perennial ryegrass, suggest that Coastcross swards optimised their LAI via clonal integration among tillers in contrast with tillers of cool-season grasses that respond more as individuals. However, this hypothesis has yet to be experimentally verified.Escola Superior de Agricultura "Luiz de Queiroz"2001-12-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162001000400002Scientia Agricola v.58 n.4 2001reponame:Scientia Agrícola (Online)instname:Universidade de São Paulo (USP)instacron:USP10.1590/S0103-90162001000400002info:eu-repo/semantics/openAccessSbrissia,André FischerSilva,Sila Carneiro daCarvalho,Carlos Augusto Brandão deCarnevalli,Roberta AparecidaPinto,Luiz Felipe de MouraFagundes,Jaílson LaraPedreira,Carlos Guilherme Silveiraeng2001-11-07T00:00:00Zoai:scielo:S0103-90162001000400002Revistahttp://revistas.usp.br/sa/indexPUBhttps://old.scielo.br/oai/scielo-oai.phpscientia@usp.br||alleoni@usp.br1678-992X0103-9016opendoar:2001-11-07T00:00Scientia Agrícola (Online) - Universidade de São Paulo (USP)false |
dc.title.none.fl_str_mv |
Tiller size/population density compensation in grazed Coastcross bermudagrass swards |
title |
Tiller size/population density compensation in grazed Coastcross bermudagrass swards |
spellingShingle |
Tiller size/population density compensation in grazed Coastcross bermudagrass swards Sbrissia,André Fischer Cynodon LAI tiller morphology |
title_short |
Tiller size/population density compensation in grazed Coastcross bermudagrass swards |
title_full |
Tiller size/population density compensation in grazed Coastcross bermudagrass swards |
title_fullStr |
Tiller size/population density compensation in grazed Coastcross bermudagrass swards |
title_full_unstemmed |
Tiller size/population density compensation in grazed Coastcross bermudagrass swards |
title_sort |
Tiller size/population density compensation in grazed Coastcross bermudagrass swards |
author |
Sbrissia,André Fischer |
author_facet |
Sbrissia,André Fischer Silva,Sila Carneiro da Carvalho,Carlos Augusto Brandão de Carnevalli,Roberta Aparecida Pinto,Luiz Felipe de Moura Fagundes,Jaílson Lara Pedreira,Carlos Guilherme Silveira |
author_role |
author |
author2 |
Silva,Sila Carneiro da Carvalho,Carlos Augusto Brandão de Carnevalli,Roberta Aparecida Pinto,Luiz Felipe de Moura Fagundes,Jaílson Lara Pedreira,Carlos Guilherme Silveira |
author2_role |
author author author author author author |
dc.contributor.author.fl_str_mv |
Sbrissia,André Fischer Silva,Sila Carneiro da Carvalho,Carlos Augusto Brandão de Carnevalli,Roberta Aparecida Pinto,Luiz Felipe de Moura Fagundes,Jaílson Lara Pedreira,Carlos Guilherme Silveira |
dc.subject.por.fl_str_mv |
Cynodon LAI tiller morphology |
topic |
Cynodon LAI tiller morphology |
description |
Several compensatory mechanisms in pastures do not allow optimisation of responses from the processes of herbage production and utilisation. Compensation due to tiller size/density relationships is one of these mechanisms. This experiment evaluated this process for Coastcross bermudagrass and compared the responses to those reported for temperate forages. Treatments were "steady state" sward surface heights of 5, 10, 15, and 20 cm that were maintained from August, 1998, through July, 1999 by sheep grazing. The experimental design was a randomised complete block, replicated four times. Pasture responses were evaluated on four separate dates (15/12/1998, 25/01/1999, 07/04/1999 and 04/07/1999) with respect to: tiller population density, tiller weight, leaf mass and leaf area per tiller and herbage mass (biomass). Tiller volume, leaf area index (LAI), tiller leaf:stem ratio and tiller leaf area:volume ratio (R) were calculated. Simple regression analyses between tiller population density and tiller weight were also performed. Coastcross swards showed a tiller size/density compensation mechanism where high tiller population densities were associated with small tillers and vice-versa; except on the last evaluation. However, regression analysis revealed linear coefficients of -3.83 to -2.05, which are lower than the theoretical expectation of -3/2. The lower R values observed, when compared to those reported for perennial ryegrass, suggest that Coastcross swards optimised their LAI via clonal integration among tillers in contrast with tillers of cool-season grasses that respond more as individuals. However, this hypothesis has yet to be experimentally verified. |
publishDate |
2001 |
dc.date.none.fl_str_mv |
2001-12-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162001000400002 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162001000400002 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1590/S0103-90162001000400002 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
text/html |
dc.publisher.none.fl_str_mv |
Escola Superior de Agricultura "Luiz de Queiroz" |
publisher.none.fl_str_mv |
Escola Superior de Agricultura "Luiz de Queiroz" |
dc.source.none.fl_str_mv |
Scientia Agricola v.58 n.4 2001 reponame:Scientia Agrícola (Online) instname:Universidade de São Paulo (USP) instacron:USP |
instname_str |
Universidade de São Paulo (USP) |
instacron_str |
USP |
institution |
USP |
reponame_str |
Scientia Agrícola (Online) |
collection |
Scientia Agrícola (Online) |
repository.name.fl_str_mv |
Scientia Agrícola (Online) - Universidade de São Paulo (USP) |
repository.mail.fl_str_mv |
scientia@usp.br||alleoni@usp.br |
_version_ |
1748936457978904576 |