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Full-Text Articles in Life Sciences
The Operculum In Pollen Of Monocotyledons, Carol A. Furness, Paula J. Rudall
The Operculum In Pollen Of Monocotyledons, Carol A. Furness, Paula J. Rudall
Aliso: A Journal of Systematic and Floristic Botany
Within monocotyledons, monosulcate pollen is the predominant type and probably represents the plesiomorphic condition, but considerable variation occurs in sulcus morphology. An operculum is an exine thickening that covers most of an aperture. Monocot opercula are usually associated with sulci, although they can occur in ulcerate apertures, as in Poaceae. There are several other aperture types closely related to the monosulcate-operculate type, and confusion occurs in the palynological literature between monosulcate-operculate, pontoperculate, disulculate, disulcate, and zona-aperturate (zonasulculate or zonasulcate) pollen. Transmission electron microscopy (TEM) was used to determine the distribution of the thick apertural intine and to accurately identify these …
Aperture Pattern And Microsporogenesis In Asparagales, Sophie Nadot, Laurent Penet, Leanne D. Dreyer, Arlette Forchioni, Adrienne Ressayre
Aperture Pattern And Microsporogenesis In Asparagales, Sophie Nadot, Laurent Penet, Leanne D. Dreyer, Arlette Forchioni, Adrienne Ressayre
Aliso: A Journal of Systematic and Floristic Botany
The aperture pattern of pollen grains is a character defined as the number, shape, and position of apertures. Although this character is highly variable in angiosperms, two states are particularly widespread. Pollen grains with one polar aperture occur frequently in basal angiosperms and monocots while tricolpate pollen is a synapomorphy of the eudicots. Many morphological characters are the result of a compromise between selective forces (acting on morphology) and developmental constraints (limiting the range of possible morphologies). To investigate what are the respective roles of development and selection in the determination of aperture pattern in angiosperms, we have chosen to …
Morphological And Palynological Investigation On Silene Gigantea L. Var. Gigantea And Silene Behen L. (Caryophyllaceae) Distributed In Western Anatolia And Northern Cyprus, Kemal Yildiz
Turkish Journal of Botany
A comparative investigation was carried out on the morphology and palynology of Silene gigantea L. var. gigantea and Silene behen L. species of the family Caryophyllaceae distributed in Western Anatolia and Northern Cyprus. An examination conducted on S. gigantea var. gigantea revealed that the calyx length in Western Anatolian specimens was shorter than that of those from Northern Cyprus, that the basal petal blades of the Western Anatolian specimens did not have any ligula while those from Northern Cyprus did, and that the petal blades belonging to the specimens from Northern Cyprus demonstrated less clefting as compared to those from …