Consulta: subjectFacets:"Exine"
Registros recuperados: 4
Data/hora: 13/06/2024 04:36:38

Palynotaxonomy of the genus Gladiopappus (Dicomeae, Asteraceae) with special emphasis on the exine ultrastructure and mesoapertures
Provedor de dados: Naturalis Digital Academic Repository
Autores: Pereira Coutinho, A.; Sá da Bandeira, D.; Currais, L.; Soukiazes, E.; Ortiz, S.
The pollen morphology of Gladiopappus vernonioides was studied with transmission (TEM) and scanning (SEM) electron microscopy and with light microscopy (LM). An Anthemoid pattern of exine ultrastructure was found. The pollen morphology of Gladiopappus supports the inclusion of this genus in the tribe Dicomeae and subtribe Dicominae but not in the Mutisieae s.str. The apertural system of G. vernonioides includes a mesoaperture that intersects the foot layer and the upper layer of the endexine, a condition already pointed out for several tribes of Asteroideae (Helenieae, Gnaphaliinae, Heliantheae, Inuleae, Senecioneae) and Carduoideae (Cardueae, Dicomeae). It is suggested that the existence of an intermediate aperture could characterize the apertural system...
Tipo: Article / Letter to the editor
Palavras-chave: Dicomeae; Exine; LM; Mutisieae; Pollen; SEM; TEM.
Ano: 2018
URL: http://www.repository.naturalis.nl/record/655821

Pollen morphology of Senecio bergii (Asteraceae), with special attention to the mesoaperture
Provedor de dados: Phyton: Revista Internacional de Botánica Experimental
Autores: Montes,B; Murray,MG.
Palynological studies contribute to understanding the taxonomy, phylogeny and ecology of the Asteraceae and other families. In this study, pollen morphology and ultrastructure of the exine of Senecio bergii Hieron. were studied using light, scanning and transmission electron microscopy. The pollen of this species is prolate-spheroidal, it has a Senecioid pattern on the exine and an apertural system composed of three apertures (ecto-, meso- and endoapertures). This pollen type is defined as tricolpororate due to the triple apertural system. This is the first description of the ultra-structure of the apertural system of the pollen of Argentine species of Senecio. The presence of mesoapertures and the description of the ultrastructure of the pollen of Senecio...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Senecio; Pollen; Exine; Mesoaperture; Ultrastructure.
Ano: 2015
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1851-56572015000100027

Comparative pollen morphological analysis in the subgenera Passiflora and Decaloba
Provedor de dados: Anais da Academia Brasileira de Ciências
Autores: SOARES,TALIANE L.; JESUS,ONILDO N.; SOUZA,EVERTON H.; ROSSI,MÔNICA L.; OLIVEIRA,EDER J.
ABSTRACT The genus Passiflora is the most diversified of the Passifloraceae, and its palynology presents wide morphological variability. The objective of the study was to evaluate the pollen morphology of 18 Passiflora species in order to identify informative pollinic characteristics to contribute to the taxonomic classification of the genus. The morphology of the pollen grains and the exine structure were investigated using light microscopy and scanning electron microscopy. Differences in the pollen morphology were found in the studied species, mainly in terms of shape, pollen aperture and ornamentation pattern of the exine. Most of the species belonging to the subgenus Passiflora presented ornamented 6-syncolpate pollen grains with an oblate-spheroidal...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Passifloraceae; Pollen grains; Scanning electron microscopy; Exine; Morphological characterization.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652018000502381

Reproductive studies in ipecac (Psychotria ipecacuanha (Brot.) stockes; Rubiaceae): pollen development and morphology
Provedor de dados: Brazilian Archives of Biology and Technology
Autores: Souza,Margarete Magalhães; Martins,Ernane Ronie; Pereira,Telma Nair Santana; Oliveira,Luiz Orlando de.
The aim of this work was to carry out the reproductive studies on Brazilian accessions of ipecac, Psychotria ipecacuanha. It presented heterostyly, with brevistylous and longistylous flowers. The pollen development was observed from the sections of the anthers embedded in resin. Anther development was normal as usually observed in dicotyledones, displaying four layers: outer epidermis, endothecium, middle layer and inner tapetum. The pollen was bicellular and filled with starch at the microspore stage. Pollen morphology was studied using SEM, which showed pollen polymorphism within and between the two floral morphs. Five types of pollen with reticulate or perforate exine were identified. The characteristics showed that the sexual process was as important...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ipecac; Heterostyly; Anther anatomy; Microsporogenesis; Exine.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132008000500015