Estudios evolutivos del desarrollo en tallos fósiles de Corystospermaceae (Corystospermales, Spermatopsida)

Evolutionary developmental studies in fossil stems of Corystospermaceae. A methodological critera to study the development of permineralized stems is proposed, which is applied in the analysis of the evodevo patterns of Corystospermaceae axes, the most important Mesozoic seed fern family in gondwani...

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Detalles Bibliográficos
Autor principal: Bodnar, Josefina
Formato: Articulo
Lenguaje:Español
Publicado: 2012
Materias:
Botánica
Heterochrony
Heterotopy
Ontogeny
Pteridosperms
Trunks
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/84408
Aporte de:
SEDICI (UNLP) de Universidad Nacional de La Plata
id I19-R120-10915-84408
record_format dspace
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Español
topic Botánica
Heterochrony
Heterotopy
Ontogeny
Pteridosperms
Trunks
spellingShingle Botánica
Heterochrony
Heterotopy
Ontogeny
Pteridosperms
Trunks
Bodnar, Josefina
Estudios evolutivos del desarrollo en tallos fósiles de Corystospermaceae (Corystospermales, Spermatopsida)
topic_facet Botánica
Heterochrony
Heterotopy
Ontogeny
Pteridosperms
Trunks
description Evolutionary developmental studies in fossil stems of Corystospermaceae. A methodological critera to study the development of permineralized stems is proposed, which is applied in the analysis of the evodevo patterns of Corystospermaceae axes, the most important Mesozoic seed fern family in gondwanic Triassic paleofloras. This group accounts for an excellent case study because their stems are preserved permineralized, showing cellular and histological details, and it is possible to examine their whole ontogeny in a single individual since the cells of the secondary xylem and phloem are produced in successive layers retaining permanently their position. In the ontogenetic studies of pteridosperms, regulating mechanisms of development must be discerned comparing with ontogenies of comparable living plants. This extrapolation is possible since it is known that regulating processes of secondary growth are homologous in all lygnophytes. Most of corystosperm axes present a dissected secondary vascular cylinder, and tissues with unusual development and position, which is caused by four classes of cambial deviations: 1-differential activity throughout the stem circumference; 2-remnant activity; 3-inverse or centripetal cambium; and 4-successive inverse and/or normal cambia (poyxyly). The origin of these cambium deviations is intimately linked to heterotopic events, including neoheterotopy and homeosis. By comparison with living plant studies, it is theorized that homeotic genes implied with these events could be those related to the beginning of cambial activity, cell differentiation, and vascular bundle arrangement.
format Articulo
Articulo
author Bodnar, Josefina
author_facet Bodnar, Josefina
author_sort Bodnar, Josefina
title Estudios evolutivos del desarrollo en tallos fósiles de Corystospermaceae (Corystospermales, Spermatopsida)
title_short Estudios evolutivos del desarrollo en tallos fósiles de Corystospermaceae (Corystospermales, Spermatopsida)
title_full Estudios evolutivos del desarrollo en tallos fósiles de Corystospermaceae (Corystospermales, Spermatopsida)
title_fullStr Estudios evolutivos del desarrollo en tallos fósiles de Corystospermaceae (Corystospermales, Spermatopsida)
title_full_unstemmed Estudios evolutivos del desarrollo en tallos fósiles de Corystospermaceae (Corystospermales, Spermatopsida)
title_sort estudios evolutivos del desarrollo en tallos fósiles de corystospermaceae (corystospermales, spermatopsida)
publishDate 2012
url http://sedici.unlp.edu.ar/handle/10915/84408
work_keys_str_mv AT bodnarjosefina estudiosevolutivosdeldesarrolloentallosfosilesdecorystospermaceaecorystospermalesspermatopsida
AT bodnarjosefina evolutionarydevelopmentalstudiesinfossilstemsofcorystospermaceae
bdutipo_str Repositorios
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