Ontogenia do óvulo e da semente de espécies de Cuspidaria e Tynanthus (Bignonieae: Bignoniaceae)

Detalhes bibliográficos
Autor(a) principal: Lozasso, Jessyca Alyne
Data de Publicação: 2016
Tipo de documento: Dissertação
Idioma: por
Título da fonte: Repositório Institucional da UFU
Texto Completo: https://repositorio.ufu.br/handle/123456789/17604
http://doi.org/10.14393/ufu.di.2016.137
Resumo: Recent studies of molecular phylogeny changed significantly the circunscription of various genera of Bignonieae-Bignoniaceae. In a later taxonomic treatment, one of its biggest genera, Arrabidaeae, considered polyphyletic, was the circunscription changed and had its species distributed in the genera Cuspidaria, Fridericia, Tanaecium and Xylophragma. Given the great conservatism of the embryological features of angiosperms, this study aimed to analyze the ovule and seed ontogeny of C. sceptrum (= Arrabidaea sceptrum), C. convoluta and Tynanthus micranthus in search of characters that support the molecular data that allowed the inclusion of Arrabidaea species in Cuspidaria, as well as that can distinguish the Cuspidaria species from his sister's group, Tynanthus. In addition to establish comparisons with Fridericia platyphylla (= Arrabidaea brachypoda), adopted as an external group. The anatropous, unitegmic tenuinucellate ovules, with an endothelium and a hypostase, and with a regular meiosis forming a linear tetrad and developing a Polygonum megagametophyte, are in accordance to the observed in earlier studies of Bignoniaceae species. The ovule primordia rising in zones II and III of the placentae differ from the previously described for other Bignoniaceae. The studied species share the origin of the integument only in the dermal layer with the tribe Jacarandeae, differing from the species of Tabebuia alliance. Cuspidaria and Fridericia species have only a series of ovules per placentae, while T. micranthus has two series of ovules per placentae, proving to be a useful feature to distinguish Cuspidaria from Tynanthus. The absence of fleshy crests placentae and the presence of an integument extension at the micropylar pole of the ovule are shared by Cuspidaria species and F. platyphylla, indicating that they can be more widely distributed in the clade Arrabidaea and allies, although they are absent in T. micranthus. The chalazal haustorium of the endosperm of the three studied species has four cells and it is shared with species of the most basal tribes of the family, Jacarandeae and Tecomeae, but differs from the finds for the Tabebuia alliance and Paleotropical clades, being an important character to distinguish tribes or higher clades. The presence of a membranous envelope composed by an endosperm with a late differentiation and by the endothelium seems to be a synapomorphy for Bignoniaceae and its ontogeny corresponds to the described in recent works. Although the late differentiated endosperm is present in the mature seed, it is scarce, not being the main source of nutrients 4 during germination, so that the seed is characterized as exalbuminous. The integument extension at the micropylar pole of the ovule did not follow the seed expansion, indicating that its function should be restricted to the floral anthesis and could favor the ovule penetration by the pollen tube. The analysis of the morphology of the hilum showed that Cuspidaria species have oval hilum, while Tynanthus species have linear hilum, with some exceptions, indicating the need for additional studies of this feature. Thus, although the results of this study are useful to distinguish Tynanthus and Cuspidaria species, they can not be used to support the new circunscription of Cuspidaria sceptrum (= Arrabidaea sceptrum).
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spelling Ontogenia do óvulo e da semente de espécies de Cuspidaria e Tynanthus (Bignonieae: Bignoniaceae)Ovule and seed ontogeny in species of Cuspidaria and Tynanthus (Bignonieae: BignoniaceaeBotânicaBignoniaceaOntogeniaMegasporogêneseOntogenia do óvuloOntogenia da sementeMegasporogenesisOvule ontogenySeed ontogenyCNPQ::CIENCIAS BIOLOGICAS::BOTANICARecent studies of molecular phylogeny changed significantly the circunscription of various genera of Bignonieae-Bignoniaceae. In a later taxonomic treatment, one of its biggest genera, Arrabidaeae, considered polyphyletic, was the circunscription changed and had its species distributed in the genera Cuspidaria, Fridericia, Tanaecium and Xylophragma. Given the great conservatism of the embryological features of angiosperms, this study aimed to analyze the ovule and seed ontogeny of C. sceptrum (= Arrabidaea sceptrum), C. convoluta and Tynanthus micranthus in search of characters that support the molecular data that allowed the inclusion of Arrabidaea species in Cuspidaria, as well as that can distinguish the Cuspidaria species from his sister's group, Tynanthus. In addition to establish comparisons with Fridericia platyphylla (= Arrabidaea brachypoda), adopted as an external group. The anatropous, unitegmic tenuinucellate ovules, with an endothelium and a hypostase, and with a regular meiosis forming a linear tetrad and developing a Polygonum megagametophyte, are in accordance to the observed in earlier studies of Bignoniaceae species. The ovule primordia rising in zones II and III of the placentae differ from the previously described for other Bignoniaceae. The studied species share the origin of the integument only in the dermal layer with the tribe Jacarandeae, differing from the species of Tabebuia alliance. Cuspidaria and Fridericia species have only a series of ovules per placentae, while T. micranthus has two series of ovules per placentae, proving to be a useful feature to distinguish Cuspidaria from Tynanthus. The absence of fleshy crests placentae and the presence of an integument extension at the micropylar pole of the ovule are shared by Cuspidaria species and F. platyphylla, indicating that they can be more widely distributed in the clade Arrabidaea and allies, although they are absent in T. micranthus. The chalazal haustorium of the endosperm of the three studied species has four cells and it is shared with species of the most basal tribes of the family, Jacarandeae and Tecomeae, but differs from the finds for the Tabebuia alliance and Paleotropical clades, being an important character to distinguish tribes or higher clades. The presence of a membranous envelope composed by an endosperm with a late differentiation and by the endothelium seems to be a synapomorphy for Bignoniaceae and its ontogeny corresponds to the described in recent works. Although the late differentiated endosperm is present in the mature seed, it is scarce, not being the main source of nutrients 4 during germination, so that the seed is characterized as exalbuminous. The integument extension at the micropylar pole of the ovule did not follow the seed expansion, indicating that its function should be restricted to the floral anthesis and could favor the ovule penetration by the pollen tube. The analysis of the morphology of the hilum showed that Cuspidaria species have oval hilum, while Tynanthus species have linear hilum, with some exceptions, indicating the need for additional studies of this feature. Thus, although the results of this study are useful to distinguish Tynanthus and Cuspidaria species, they can not be used to support the new circunscription of Cuspidaria sceptrum (= Arrabidaea sceptrum).Fundação de Amparo a Pesquisa do Estado de Minas GeraisDissertação (Mestrado)Estudos recentes de filogenia molecular alteraram de forma significativa a circunscrição de diversos gêneros de Bignonieae-Bignoniaceae. Em um tratamento taxonômico posterior, um de seus maiores gêneros, Arrabidaeae, considerado polifilético, teve sua circunscrição alterada e suas espécies distribuídas nos gêneros Cuspidaria, Fridericia, Tanaecium e Xylophragma. Dado o grande conservadorismo das características embriológicas de angiospermas, o presente trabalho teve como objetivo analisar a ontogenia do óvulo e da semente de C. sceptrum (= Arrabidaea sceptrum), C. convoluta e Tynanthus micranthus em busca de caracteres que corroboram os dados moleculares que permitiram a inclusão de espécies de Arrabidaea em Cuspidaria, bem como que possam distinguir as espécies de Cuspidaria de seu grupo irmão, Tynanthus. Além de estabelecer comparações com Fridericia platyphylla (= Arrabidaea brachypoda) adotada como um grupo externo. Os óvulos anátropos, unitegumentados, tenuinucelados com presença de endotélio e hipóstase diferenciada, a meiose regular, com formação de uma tétrade linear e desenvolvimento do megagametófito do tipo Polygonum, seguem de acordo com o que foi observado nas espécies de Bignoniaceae anteriormente estudadas. A elevação dos primórdios de óvulos através de divisões celulares nas zonas II e III da placenta difere do já descrito para as demais Bignoniaceae. As espécies estudadas compartilham o fato de o tegumento ter sido originado apenas pela camada epidérmica com a tribo Jacarandeae, diferindo das espécies de Tabebuia alliance. As espécies de Cuspidaria e Fridericia possuem apenas uma série de óvulos por placenta, enquanto T. micranthus apresenta duas séries por placenta, demonstrando ser uma característica útil para distinguir Cuspidaria de Tynanthus. A ausência de cristas placentíferas carnosas e presença de um prolongamento na região micropilar do óvulo são compartilhadas pelas espécies de Cuspidaria e F. platyphylla, indicando que possam ser mais amplamente distribuídas no clado Arrabidaea and allies, embora estejam ausentes em T. micranthus. O haustório calazal do endosperma das três espécies estudadas possui quatro células e esse caráter é compartilhado com espécies das tribos mais basais da família, Jacarandeae e Tecomeae, mas difere do encontrado para os clados Tabebuia alliance e Paleotropical clade, sendo um caráter importante para diferenciar tribos ou clados superiores. A presença de um envoltório membranáceo composto por endosperma diferenciado tardiamente e endotélio 2 parece ser uma sinapomorfia para Bignoniaceae e sua ontogenia corresponde ao descrito em trabalhos mais recentes. Embora o endosperma diferenciado tardiamente esteja presente na semente madura, ele é escasso, não sendo a principal fonte de nutrientes durante a germinação, de forma que a semente é caracterizada como exalbuminosa. O prolongamento do tegumento na região micropilar não acompanha a expansão da semente, indicando que sua função deve estar restrita à antese floral podendo favorecer a penetração do óvulo pelo tubo polínico. A análise da morfologia do hilo demonstrou que as espécies de Cuspidaria possuem hilos arredondados, enquanto as de Tynanthus possuem hilos lineares, com algumas exceções que indicam a necessidade de estudos adicionais para esta característica. Dessa forma, embora os resultados deste estudo sejam úteis para separar espécies Tynanthus e Cuspidaria, eles não podem ser utilizados para corroborar a nova circunscrição de Cuspidaria sceptrum (= Arrabidaea sceptrum).Univerdade Federal de UberlândiaBrasilPrograma de Pós-graduação em Biologia VegetalSampaio, Diana Salleshttp://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4739632H8Bittencourt Júnior, Nelson Sabinohttp://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4784911Z5Marzinek, Julianahttp://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4700020U5Lozasso, Jessyca Alyne2016-08-05T17:24:43Z2016-08-05T17:24:43Z2016-02-25info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfLOZASSO, Jessyca Alyne. Ontogenia do óvulo e da semente de espécies de Cuspidaria e Tynanthus (Bignonieae: Bignoniaceae). 2016. 123 f. Dissertação (Mestrado em Biologia Vegetal) - Universidade Federal de Uberlândia, Uberlândia, 2016. DOI http://doi.org/10.14393/ufu.di.2016.137https://repositorio.ufu.br/handle/123456789/17604http://doi.org/10.14393/ufu.di.2016.137porinfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UFUinstname:Universidade Federal de Uberlândia (UFU)instacron:UFU2020-09-24T22:17:25Zoai:repositorio.ufu.br:123456789/17604Repositório InstitucionalONGhttp://repositorio.ufu.br/oai/requestdiinf@dirbi.ufu.bropendoar:2020-09-24T22:17:25Repositório Institucional da UFU - Universidade Federal de Uberlândia (UFU)false
dc.title.none.fl_str_mv Ontogenia do óvulo e da semente de espécies de Cuspidaria e Tynanthus (Bignonieae: Bignoniaceae)
Ovule and seed ontogeny in species of Cuspidaria and Tynanthus (Bignonieae: Bignoniaceae
title Ontogenia do óvulo e da semente de espécies de Cuspidaria e Tynanthus (Bignonieae: Bignoniaceae)
spellingShingle Ontogenia do óvulo e da semente de espécies de Cuspidaria e Tynanthus (Bignonieae: Bignoniaceae)
Lozasso, Jessyca Alyne
Botânica
Bignoniacea
Ontogenia
Megasporogênese
Ontogenia do óvulo
Ontogenia da semente
Megasporogenesis
Ovule ontogeny
Seed ontogeny
CNPQ::CIENCIAS BIOLOGICAS::BOTANICA
title_short Ontogenia do óvulo e da semente de espécies de Cuspidaria e Tynanthus (Bignonieae: Bignoniaceae)
title_full Ontogenia do óvulo e da semente de espécies de Cuspidaria e Tynanthus (Bignonieae: Bignoniaceae)
title_fullStr Ontogenia do óvulo e da semente de espécies de Cuspidaria e Tynanthus (Bignonieae: Bignoniaceae)
title_full_unstemmed Ontogenia do óvulo e da semente de espécies de Cuspidaria e Tynanthus (Bignonieae: Bignoniaceae)
title_sort Ontogenia do óvulo e da semente de espécies de Cuspidaria e Tynanthus (Bignonieae: Bignoniaceae)
author Lozasso, Jessyca Alyne
author_facet Lozasso, Jessyca Alyne
author_role author
dc.contributor.none.fl_str_mv Sampaio, Diana Salles
http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4739632H8
Bittencourt Júnior, Nelson Sabino
http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4784911Z5
Marzinek, Juliana
http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4700020U5
dc.contributor.author.fl_str_mv Lozasso, Jessyca Alyne
dc.subject.por.fl_str_mv Botânica
Bignoniacea
Ontogenia
Megasporogênese
Ontogenia do óvulo
Ontogenia da semente
Megasporogenesis
Ovule ontogeny
Seed ontogeny
CNPQ::CIENCIAS BIOLOGICAS::BOTANICA
topic Botânica
Bignoniacea
Ontogenia
Megasporogênese
Ontogenia do óvulo
Ontogenia da semente
Megasporogenesis
Ovule ontogeny
Seed ontogeny
CNPQ::CIENCIAS BIOLOGICAS::BOTANICA
description Recent studies of molecular phylogeny changed significantly the circunscription of various genera of Bignonieae-Bignoniaceae. In a later taxonomic treatment, one of its biggest genera, Arrabidaeae, considered polyphyletic, was the circunscription changed and had its species distributed in the genera Cuspidaria, Fridericia, Tanaecium and Xylophragma. Given the great conservatism of the embryological features of angiosperms, this study aimed to analyze the ovule and seed ontogeny of C. sceptrum (= Arrabidaea sceptrum), C. convoluta and Tynanthus micranthus in search of characters that support the molecular data that allowed the inclusion of Arrabidaea species in Cuspidaria, as well as that can distinguish the Cuspidaria species from his sister's group, Tynanthus. In addition to establish comparisons with Fridericia platyphylla (= Arrabidaea brachypoda), adopted as an external group. The anatropous, unitegmic tenuinucellate ovules, with an endothelium and a hypostase, and with a regular meiosis forming a linear tetrad and developing a Polygonum megagametophyte, are in accordance to the observed in earlier studies of Bignoniaceae species. The ovule primordia rising in zones II and III of the placentae differ from the previously described for other Bignoniaceae. The studied species share the origin of the integument only in the dermal layer with the tribe Jacarandeae, differing from the species of Tabebuia alliance. Cuspidaria and Fridericia species have only a series of ovules per placentae, while T. micranthus has two series of ovules per placentae, proving to be a useful feature to distinguish Cuspidaria from Tynanthus. The absence of fleshy crests placentae and the presence of an integument extension at the micropylar pole of the ovule are shared by Cuspidaria species and F. platyphylla, indicating that they can be more widely distributed in the clade Arrabidaea and allies, although they are absent in T. micranthus. The chalazal haustorium of the endosperm of the three studied species has four cells and it is shared with species of the most basal tribes of the family, Jacarandeae and Tecomeae, but differs from the finds for the Tabebuia alliance and Paleotropical clades, being an important character to distinguish tribes or higher clades. The presence of a membranous envelope composed by an endosperm with a late differentiation and by the endothelium seems to be a synapomorphy for Bignoniaceae and its ontogeny corresponds to the described in recent works. Although the late differentiated endosperm is present in the mature seed, it is scarce, not being the main source of nutrients 4 during germination, so that the seed is characterized as exalbuminous. The integument extension at the micropylar pole of the ovule did not follow the seed expansion, indicating that its function should be restricted to the floral anthesis and could favor the ovule penetration by the pollen tube. The analysis of the morphology of the hilum showed that Cuspidaria species have oval hilum, while Tynanthus species have linear hilum, with some exceptions, indicating the need for additional studies of this feature. Thus, although the results of this study are useful to distinguish Tynanthus and Cuspidaria species, they can not be used to support the new circunscription of Cuspidaria sceptrum (= Arrabidaea sceptrum).
publishDate 2016
dc.date.none.fl_str_mv 2016-08-05T17:24:43Z
2016-08-05T17:24:43Z
2016-02-25
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
dc.type.driver.fl_str_mv info:eu-repo/semantics/masterThesis
format masterThesis
status_str publishedVersion
dc.identifier.uri.fl_str_mv LOZASSO, Jessyca Alyne. Ontogenia do óvulo e da semente de espécies de Cuspidaria e Tynanthus (Bignonieae: Bignoniaceae). 2016. 123 f. Dissertação (Mestrado em Biologia Vegetal) - Universidade Federal de Uberlândia, Uberlândia, 2016. DOI http://doi.org/10.14393/ufu.di.2016.137
https://repositorio.ufu.br/handle/123456789/17604
http://doi.org/10.14393/ufu.di.2016.137
identifier_str_mv LOZASSO, Jessyca Alyne. Ontogenia do óvulo e da semente de espécies de Cuspidaria e Tynanthus (Bignonieae: Bignoniaceae). 2016. 123 f. Dissertação (Mestrado em Biologia Vegetal) - Universidade Federal de Uberlândia, Uberlândia, 2016. DOI http://doi.org/10.14393/ufu.di.2016.137
url https://repositorio.ufu.br/handle/123456789/17604
http://doi.org/10.14393/ufu.di.2016.137
dc.language.iso.fl_str_mv por
language por
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 Univerdade Federal de Uberlândia
Brasil
Programa de Pós-graduação em Biologia Vegetal
publisher.none.fl_str_mv Univerdade Federal de Uberlândia
Brasil
Programa de Pós-graduação em Biologia Vegetal
dc.source.none.fl_str_mv reponame:Repositório Institucional da UFU
instname:Universidade Federal de Uberlândia (UFU)
instacron:UFU
instname_str Universidade Federal de Uberlândia (UFU)
instacron_str UFU
institution UFU
reponame_str Repositório Institucional da UFU
collection Repositório Institucional da UFU
repository.name.fl_str_mv Repositório Institucional da UFU - Universidade Federal de Uberlândia (UFU)
repository.mail.fl_str_mv diinf@dirbi.ufu.br
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