Germination constraints of dicarpic cypselae of Bidens pilosa L.
Autor(a) principal: | |
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Data de Publicação: | 2019 |
Outros Autores: | |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UNESP |
Texto Completo: | http://dx.doi.org/10.1590/1519-6984.178222 http://hdl.handle.net/11449/187594 |
Resumo: | Bidens pilosa L. is a heterocarpic weed species with two cypselae types that present morpho-physiological differences, being the peripheral type smaller and slower to germinate than the central one. We aimed to verify how the germination mechanism varied between types. We focused on two mechanisms: (1) pericarp constraints (physical and chemical) and (2) hormonal stimulation (Abcisic acid [ABA] and Gibberellin [GA]). Both cypselae types are physically constrained by the pericarp, for when it is excised both seed types increase their germination, but behavioral differences still remain. The pericarp of the peripheral type also has chemical inhibitors that effectively inhibited germination of the intact central cypsela. To test the hormonal effects, we focused on the ABA:GA control. Both cypselae responded to an exogenous ABA concentration gradient, however there is no variation between types on the sensitivity to it. Also, both cypselae types were indifferent to Fluridone (ABA inhibitor), which indicates that the dormancy is not maintained by de novo ABA synthesis. Cypselae types had different sensitivity to an exogenous GA3 gradient, the central type being more sensitive to the treatment than the peripheral one. But when the endogenous GA synthesis was blocked by Paclobutrazol, both types responded equally to same GA3 concentrations. This indicates that endogenous GA synthesis may be related to differences observed on germination of cypselae types. To conclude, seed types differ on their growth potential to overcome the pericarp resistance: while the inhibitor in the peripheral pericarp reduces growth potential, GA increases it. |
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Germination constraints of dicarpic cypselae of Bidens pilosa L.Restrições a germinação de cipselas dicárpicas de Bidens pilosa L.Heteromophic diasporesHormonal controllingPericarp inhibitionBidens pilosa L. is a heterocarpic weed species with two cypselae types that present morpho-physiological differences, being the peripheral type smaller and slower to germinate than the central one. We aimed to verify how the germination mechanism varied between types. We focused on two mechanisms: (1) pericarp constraints (physical and chemical) and (2) hormonal stimulation (Abcisic acid [ABA] and Gibberellin [GA]). Both cypselae types are physically constrained by the pericarp, for when it is excised both seed types increase their germination, but behavioral differences still remain. The pericarp of the peripheral type also has chemical inhibitors that effectively inhibited germination of the intact central cypsela. To test the hormonal effects, we focused on the ABA:GA control. Both cypselae responded to an exogenous ABA concentration gradient, however there is no variation between types on the sensitivity to it. Also, both cypselae types were indifferent to Fluridone (ABA inhibitor), which indicates that the dormancy is not maintained by de novo ABA synthesis. Cypselae types had different sensitivity to an exogenous GA3 gradient, the central type being more sensitive to the treatment than the peripheral one. But when the endogenous GA synthesis was blocked by Paclobutrazol, both types responded equally to same GA3 concentrations. This indicates that endogenous GA synthesis may be related to differences observed on germination of cypselae types. To conclude, seed types differ on their growth potential to overcome the pericarp resistance: while the inhibitor in the peripheral pericarp reduces growth potential, GA increases it.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Centro Multidisciplinar da Barra Universidade Federal do Oeste da Bahia – UFOB, Avenida 23 de Agosto, s/nLaboratório de Fotomorfogênese de Plantas Departamento de Botânica Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” – UNESP, Avenida 24-A, 1515Laboratório de Fotomorfogênese de Plantas Departamento de Botânica Instituto de Biociências Universidade Estadual Paulista “Júlio de Mesquita Filho” – UNESP, Avenida 24-A, 1515CNPq: 147810/2010-8Universidade Federal do Oeste da Bahia – UFOBUniversidade Estadual Paulista (Unesp)Souza-Filho, P. R.M.Takaki, M. [UNESP]2019-10-06T15:41:17Z2019-10-06T15:41:17Z2019-01-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article383-394application/pdfhttp://dx.doi.org/10.1590/1519-6984.178222Brazilian Journal of Biology, v. 79, n. 3, p. 383-394, 2019.1678-43751519-6984http://hdl.handle.net/11449/18759410.1590/1519-6984.178222S1519-698420190003003832-s2.0-85064722620S1519-69842019000300383.pdfScopusreponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengBrazilian Journal of Biologyinfo:eu-repo/semantics/openAccess2023-11-02T06:07:06Zoai:repositorio.unesp.br:11449/187594Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462024-08-05T16:42:10.863074Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false |
dc.title.none.fl_str_mv |
Germination constraints of dicarpic cypselae of Bidens pilosa L. Restrições a germinação de cipselas dicárpicas de Bidens pilosa L. |
title |
Germination constraints of dicarpic cypselae of Bidens pilosa L. |
spellingShingle |
Germination constraints of dicarpic cypselae of Bidens pilosa L. Souza-Filho, P. R.M. Heteromophic diaspores Hormonal controlling Pericarp inhibition |
title_short |
Germination constraints of dicarpic cypselae of Bidens pilosa L. |
title_full |
Germination constraints of dicarpic cypselae of Bidens pilosa L. |
title_fullStr |
Germination constraints of dicarpic cypselae of Bidens pilosa L. |
title_full_unstemmed |
Germination constraints of dicarpic cypselae of Bidens pilosa L. |
title_sort |
Germination constraints of dicarpic cypselae of Bidens pilosa L. |
author |
Souza-Filho, P. R.M. |
author_facet |
Souza-Filho, P. R.M. Takaki, M. [UNESP] |
author_role |
author |
author2 |
Takaki, M. [UNESP] |
author2_role |
author |
dc.contributor.none.fl_str_mv |
Universidade Federal do Oeste da Bahia – UFOB Universidade Estadual Paulista (Unesp) |
dc.contributor.author.fl_str_mv |
Souza-Filho, P. R.M. Takaki, M. [UNESP] |
dc.subject.por.fl_str_mv |
Heteromophic diaspores Hormonal controlling Pericarp inhibition |
topic |
Heteromophic diaspores Hormonal controlling Pericarp inhibition |
description |
Bidens pilosa L. is a heterocarpic weed species with two cypselae types that present morpho-physiological differences, being the peripheral type smaller and slower to germinate than the central one. We aimed to verify how the germination mechanism varied between types. We focused on two mechanisms: (1) pericarp constraints (physical and chemical) and (2) hormonal stimulation (Abcisic acid [ABA] and Gibberellin [GA]). Both cypselae types are physically constrained by the pericarp, for when it is excised both seed types increase their germination, but behavioral differences still remain. The pericarp of the peripheral type also has chemical inhibitors that effectively inhibited germination of the intact central cypsela. To test the hormonal effects, we focused on the ABA:GA control. Both cypselae responded to an exogenous ABA concentration gradient, however there is no variation between types on the sensitivity to it. Also, both cypselae types were indifferent to Fluridone (ABA inhibitor), which indicates that the dormancy is not maintained by de novo ABA synthesis. Cypselae types had different sensitivity to an exogenous GA3 gradient, the central type being more sensitive to the treatment than the peripheral one. But when the endogenous GA synthesis was blocked by Paclobutrazol, both types responded equally to same GA3 concentrations. This indicates that endogenous GA synthesis may be related to differences observed on germination of cypselae types. To conclude, seed types differ on their growth potential to overcome the pericarp resistance: while the inhibitor in the peripheral pericarp reduces growth potential, GA increases it. |
publishDate |
2019 |
dc.date.none.fl_str_mv |
2019-10-06T15:41:17Z 2019-10-06T15:41:17Z 2019-01-01 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://dx.doi.org/10.1590/1519-6984.178222 Brazilian Journal of Biology, v. 79, n. 3, p. 383-394, 2019. 1678-4375 1519-6984 http://hdl.handle.net/11449/187594 10.1590/1519-6984.178222 S1519-69842019000300383 2-s2.0-85064722620 S1519-69842019000300383.pdf |
url |
http://dx.doi.org/10.1590/1519-6984.178222 http://hdl.handle.net/11449/187594 |
identifier_str_mv |
Brazilian Journal of Biology, v. 79, n. 3, p. 383-394, 2019. 1678-4375 1519-6984 10.1590/1519-6984.178222 S1519-69842019000300383 2-s2.0-85064722620 S1519-69842019000300383.pdf |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Brazilian Journal of Biology |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
383-394 application/pdf |
dc.source.none.fl_str_mv |
Scopus reponame:Repositório Institucional da UNESP instname:Universidade Estadual Paulista (UNESP) instacron:UNESP |
instname_str |
Universidade Estadual Paulista (UNESP) |
instacron_str |
UNESP |
institution |
UNESP |
reponame_str |
Repositório Institucional da UNESP |
collection |
Repositório Institucional da UNESP |
repository.name.fl_str_mv |
Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP) |
repository.mail.fl_str_mv |
|
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1808128688194060288 |