Microspore Morphology of Isoetes Species (Lycophyta) from Southern South America

Microspores of the 24 species of Isoetes that grow in southern South America were analyzed under a light microscope and scanning electron microscope. The microspores are monolete, elliptic in polar view, 30–40 µm long, and 20–25 µm wide. A background with various characteristics is seen on each surf...

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Detalles Bibliográficos
Autores: Macluf, Carmen Cecilia, Morbelli, Marta Alicia, Giudice, Gabriela Elena
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2006
País:Argentina
Institución:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/135356
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/135356
Access Level:acceso abierto
Palabra clave:Botánica
Sud América
Isoetes
Microsporas
Morfología
Escultura
Descripción
Sumario:Microspores of the 24 species of Isoetes that grow in southern South America were analyzed under a light microscope and scanning electron microscope. The microspores are monolete, elliptic in polar view, 30–40 µm long, and 20–25 µm wide. A background with various characteristics is seen on each surface. A supra-laesural expansion is present. The perispore is ornamented and has a perforated background. In section, it has a lacunose structure. The exospore is smooth, and it has a compact structure in section. The studied species could be divided into three groups by their perispore ornamentation: equinate, rugulate, and tuberculate. Microspore size was positively correlated with increasing ploidy level, and larger microspores were associated with terrestrial habitats. A convergence in ornamentation was found between spores produced by the studied species and those that grow in regions outside of the area under study.