Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves

La Plata, Argentina

Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves

La Plata, Argentina

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Passarelli L.M.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves | Tur N.M.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves
Revista de Biologia Tropical | Year: 2010

Pollen morphology of neotropical species of Podostemum is described for the first time with light (LM) and scanning electronic microscopes (SEM), using pollen dehydration by critical point. Herbarium specimens under study are P. comatum, P. distichum, P. muelleri and P. rutifolium. Pollen grains are dispersed in dyads. Observed with LM, dyads range from 21 to 31μm in lengh and 12 to 18μm wide. individual pollen grains are radially symmetrical spheroidal to subprolate, and have a tricolpate aperture. The exine is tectate, psilate, with an infratectal structure formed by simple columella under the tectum. With SEM, an abundant pollen surface coat is observed all over the pollen grains, mainly in the two grains dyad contact zone. This pollen coat would protect the grains from dehydration because the environments in which these plants grow have important water variation and pollination is not zoophilic. The shared dyad wall shows bridges that partially fusion the exines, forming calymate dyads. Some dyads bear the apertures aligned between grains and some not. The transverse condition of the aperture or aperture in "L" that occurs in the four studied species is described for the first time. it is interpreted as a trend of the genus to espiroaperture. This change in the aperture would be associated with phenology because it is a genus with very short flowering and anthesis, generally a day of anthesis in the dry season. The spiroaperture increases the chances of germination sites and would also have a harmomegata role in an environment with water changes favoring the reproductive success.Walls have a microechinate sculpture, with or without pads at the base of the microechinae. Size of ornamental processes differs, and the colpus membrane has similar ornamentation to that of the non apertural wall, but with larger processes. individual morphology of pollen grains is similar to that described for other family genera as Apinagia and Mourera. During previous stages of anthesis, the presence of cross tetrads was observed, also a new contribution for this genus.


Gonzalez G.E.,University of Buenos Aires | Prada C.,Complutense University of Madrid | Rolleri C.H.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves
Gayana - Botanica | Year: 2010

A new chromosome count on Blechnum hastatum, together with the study of the ontogeny and development of the leptosporangia of this taxon, and of B. occidentale is carried out here. Adult leptosporangia of other taxa of the genus Blechnum, such as those of B. australe subsp. auriculatum, B. glandulosum and B. mochaenum subsp. mochaenum are also compared. In relation with the cytology of B. hastatum, 33 bivalents at diakinesis were counted, indicating that it is a diploid with a chromosome number 2n=66, which coincides with a previous count, and also places the taxon in the sequence of basic chromosome numbers known for the genus, ie x=33, which seems to be the most frequent. The ontogeny of the leptosporangia was studied for the first time in B. hastatum and B. occidentale. The sporangia initiate from a single initial epidermal cell, which may belong to the commissural area or to the indusia; they develop a long pedicel with three rows of long or short cells, short cells being the most common condition found in B. hastatum, while long cells were seen in B. occidentale. The pedicels are at their maximum length before the capsule ripens. The stomium usually bears no more than 6-8 cells in all species, with a labiate aperture. The capsules have an indurated vertical annulus, that reach the base of the capsule, and have up to 14 cells in B. australe subsp. auriculatum and B. glandulosum, up to 18 in B. hastatum and up to 21 in B. mochaenum subsp. mochaenum and B. occidentale; the number of indurate cells may be a new useful diagnostic trait in the genus.


Rolleri C.H.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves | Martinez O.G.,National University of Salta | Prada C.,Complutense University of Madrid
Botanica Complutensis | Year: 2010

Huperzia reflexa and Lycopodiella cernua are recorded for the first time for the northwest of Argentina; along with the new records, the characters of the leaf morphology and spores are analyzed, and updated descriptions and geographical distribution of both taxa are also given. Three of the four genera of the Lycopodiaceae are present so far in the area: Huperzia, Lycopodium and Lycopodiella, and the number of species come to nine. To facilitate the recognition of all taxa, this paper also includes a key for their determination.


Gabriel Y Galan J.M.,Complutense University of Madrid | Prada C.,Complutense University of Madrid | Rolleri C.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves | Ainouche A.,French National Center for Scientific Research | Vicent M.,Complutense University of Madrid
Turkish Journal of Botany | Year: 2013

Blechnaceae is an important leptosporangiate family (9-10 genera, about 250 species). It is monophyletic and distributed mainly in tropical America and Australasia. Among the species 80% belong to Blechnum, a genus with a very complex taxonomy and uncertain internal relationships. In terms of American diversity, the results of morphological studies have arrived at 8 informal groups. Molecular works on this genus are scarce, and there is no information for the majority of American species. The main objective of this work was to evaluate whether the groups proposed to organise the diversity of American of Blechnum are consistent with a molecular analysis. We sequenced 2 chloroplastic regions from species representing all of the groups. In our molecular analysis most of the informal groups were maintained as well supported clades. Only 2 species, B. brasiliense and B. spicant, appear to be isolated from their alleged relatives. Combining our molecular results with previous morphological knowledge, we propose the recognition of 4 lineages: 1) B. serrulatum, 2) B. spicant, and 3) core Blechnum, which represents a large clade that can be divided into core Blechnum I (arborescent species, cordatoids, and B. brasiliense) and core Blechnum II (epiphytic species and herbaceous terrestrials, both monomorphic and dimorphic groups). © TÜBİTAK.


Dedomenici A.C.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves | Leveratto D.,National University of La Plata | Ringuelet J.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves | Passarelli L.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves
Botanica Complutensis | Year: 2011

A study of the pollen present in honey from an apiary located in the area of the Depresion del Salado, Buenos Aires, Argentina, in order to observe the plants used by Apis meilifera L. in an environment that has been affected by periodic floods that changed the vegetation, and making comparisons with existing data. Thirty one pollen types belonging to fifteen botanical families were identified. All samples were monofloral of Lotus tenuis with high percentages, above 50%. The results show significant variation respect to previous data on resources used by the honeybee in this area. It makes a new contribution to knowledge of the floral origin of honey from the region that will affect their commercial value.


Baran E.J.,National University of La Plata | Rolleri C.H.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves
Revista Brasileira de Botanica | Year: 2010

Frond samples of the eusporangiate ferns Marattiaceae genera Angiopteris, Christensenia, Danaea and Marattia were investigated by infrared spectroscopy, under different experimental conditions. The results confirmed the previously reported accumulation of biogenic silica (SiO2) in tissues of these ferns and also showed, for the first time, the presence of calcium oxalate in this group of plants, probably as weddellite. The ability to biomineralize SiO2, to produce and accumulate biogenic silica, is suggested now to be a general family trait of the Marattiaceae.


Baran E.J.,National University of La Plata | Gonzalez-Baro A.C.,National University of La Plata | Ciciarelli M.M.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves | Rolleri C.H.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves
Revista de Biologia Tropical | Year: 2010

Plant biominerals are not always well characterized, although this information is important for plant physiology and can be useful for taxonomic purposes. In this work, fresh plant material of seven wild neotropical species of genus Canna, C. ascendens, C. coccinea, C. indica, C. glauca, C. plurituberosa, C. variegatifolia and C. fuchsina sp. ined., taken from different habitats, were studied to characterize the biominerals in their internal tissues. For the first time, samples from primary and secondary veins of leaves were investigated by means of infrared spectroscopy, complemented with X-ray powder diffractometry and scanning electron microscopy. The spectroscopic results, supported by X-ray powder diffractometry, suggest that the calcium oxalate is present in the form of whewellite (CaC2O4×H2O) in all the investigated samples. It is interesting to emphasize that all IR spectra obtained were strongly similar in all species studied, thus indicating an identical chemical composition in terms of the biominerals found. In this sense, the results suggest that the species of Canna show similar ability to produce biogenic silica and produce an identical type of calcium oxalate within their tissues. These results can be an additional trait to support the relationship among the families of Zingiberales.


De Las Mercedes Ciciarelli M.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves | Rolleri C.H.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves | Dubox M.C.G.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves
Botanica Complutensis | Year: 2010

Cannafuchsina is a name proposed to designate a new species of the genus Canna. The species grows in wild, dense colonies, which individuals bear large, intense fuchsia colored flowers, that reproduce sexually; plants thrive in humid, riverside coastal areas and small wetlands from Buenos Aires and Santa Fe Provinces, Argentina. After the study of their phenology and morphology, conclusions are that normal pollen grains and fruits are produced, and seed develops naturally in wild and in vim conditions. The individuals of C.fuchsina resembles others belonging to the C. × generalis group, both in some vegetative and floral characters, such as the presence of wide staminodia. However, the name C.fuchsina must be applied only to the wild individuals that bear fuchsia colored flowers, since C. × generalis refers to a wide, not well characterized variety of taxa, with flowers of different colors and sizes. The characters of C.fuchsina are consistent with those of similar individuals with fuchsia colored flowers from United States and Australia, also linked to the group C. × generalis. C.fuchsina is considered the result of naturalization, after the introduction and spread of the group said, as ornamentals, since establish independent breeding colonies. A detailed description of the species, its morphology and ecology are given; the affinities with other wild species of Canna, and the importance of new characters in the systematics of the genus are also discussed.


Ciciarelli M.M.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves | Passarelli L.M.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves | Rolleri C.H.,Laboratorio Of Estudios Of Anatomia Vegetal Evolutiva Y Sistematica Leaves
Revista de Biologia Tropical | Year: 2010

The morphology of pollen grains of eight taxa of Canna, C. ascendens, C. coccinea, C. compacta, C. glauca, C. indica, C. paniculata, C. variegatifolia and C. fuchsina, an unpublished new species, were studied using light and scanning electronic microscopes. We used the Wodehouse technique on samples of 20 grains per specimen to measure the intine with a light microscope; and the density of spines (in 400μm2 fields) with scanning electronic microscopy. Pollen grains are spherical, echinate, omniaperturate. The sporoderm presents a very thin exine cov ering a thicker intine. Corrugate micro-perforate, sub-reticulate, rugate, rugulate, striate to folded, micro-striate, micro-granulate, and smooth types of the external surface of the sporoderm were found. The spines consist of exine, partially to completely covered by tryphine. The two-layered intine is the thicker part of the wall. Echinate ornamentation is a generic character in Canna, but size, surface and color of pollen walls, and density and shape of spines, are diagnostic for species. Pollen morphology supports the view of C. indica and C. coccinea as different species. Canna fuchsina grows in wild, dense colonies, in humid riverside forests from Buenos Aires and Santa Fe Provinces, Argentina; its characters suggest relationships with a not well known group of taxa, some of them hybrids, such as C. x generalis. However, as these plants showed normal, well formed grains, close to those of C. coccinea, that germinate over the stigmatic surfaces in fresh flowers, we decided to include their pollen in this study.

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