Sporophyte morphology and gametophyte development of the fern Blechnum sprucei (Pteridophyta: Blechnaceae)
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منابع مشابه
Sporophyte morphology and gametophyte development of the fern Blechnum sprucei (Pteridophyta: Blechnaceae).
The fern Blechnum sprucei grows in Mesoamerica (Costa Rica) and South America, from Colombia to Bolivia, SE and centre of Brazil, Paraguay and Argentina. It is a distinctive, somewhat vulnerable, mostly orophilous species. Fresh and dry herbarium material was used for this study. Herbarium material for anatomical studies comes from CTES, BA, LP, MA, SI and UC (Holmgren et al. 1990). Selected re...
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The nutrition of the sporophyte in Sphaerocarpos and liverworts in general has long been controversial . It has not yet been determined whether the chloroplasts in the sporophyte capsule do, in fact, photosynthesize or whether the carbohydrates stored as starch are translocated to the sporophyte from the gametophyte which is known to be photosynthetic and to which the sporophyte remains attache...
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Biometry of stomata in Blechnum species (Blechnaceae) with some taxonomic and ecological implications for the ferns.
Morphological stomatal traits, such as size, form and frequency, have been subject of much literature, including their relationships with environmental factors. However, little effort have focused on ferns, and very few in the genus Blechnum. Stomatal length, width and frequency (as stomatal index) of a number of specimens of fourteen Neotropical species of Blechnum were measured in adult pinna...
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Leaves are lateral determinate structures formed in a predictable sequence (phyllotaxy) on the flanks of an indeterminate shoot apical meristem. The origin and evolution of leaves in vascular plants has been widely debated. Being the main conspicuous organ of nearly all vascular plants and often easy to recognize as such, it seems surprising that leaves have had multiple origins. For decades, m...
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ژورنال
عنوان ژورنال: Revista de Biología Tropical
سال: 2007
ISSN: 2215-2075,0034-7744
DOI: 10.15517/rbt.v56i4.5777