Search results for "Botanica"
showing 10 items of 1665 documents
Distribution, ecology, vegetation and conservation survey on the relictual population ofCarex panormitanaGuss. (Cyperaceae) in Sicily (Italy)
2013
We report the results of research on the Carex panormitana Guss. (Cyperaceae) population in Sicily, carried out within its locus classicus at the Oreto River (Palermo). The survey led to a morphological, biological and autoecological characterization, to the definition of the current distribution in the site, to an estimate of the number of individuals and to an analysis of its conservation status. The risk status was also assessed and the species was ascribed to the category Critically Endangered (CR), in accordance with the CR B1ab (ii, iii, v) and EN C1 IUCN criteria. Moreover, the phytosociological survey carried out on the meso-hygrophilous vegetation in which the species is dominant a…
Esperienze finalizzate alla gestione conservativa dei boschi di faggio in Sicilia
2009
Con riferimento ai boschi di faggio del Parco naturale dei Nebrodi, in Sicilia, vengono esposti i risultati di un particolare intervento di conversione di un ceduo in fustaia. Il metodo prescelto è quello della matricinatura intensiva con rilascio del materiale di risulta triturato sul posto.
Reviewing the identity of the Maltese Polypodium (Polypodiaceae) – new evidence from morphology and flow cytometry
2020
The first record of Polypodium from Gozo (Maltese Islands) was described as a new endemic taxon, Polypodium vulgare subsp. melitense, based on its unique set of morphological characters. It was treated as a novelty and designated as a subspecies of P. vulgare mainly due to the lack of paraphyses, the presence of 10–16 annular cells, and a mean spore length of 64 μm. The fern was reassessed by us employing a more rigid morphological analysis and the application of flow cytometry. The absence of paraphyses was confirmed, but the number of annular cells (5–11) and the spore length (70–79 μm) differed from the previous study. These and other morphological traits, the phenology (leaf-shedding in…
New records of Characeae for Sicily (Italy)
2018
During the last year, the first two authors continued their survey of the scarcely known Characeae flora of the island of Sicily: plants were collected in different periods, habitats and areas of the island, and identifications – made on fresh material – were based mainly on Mouronval et al. (2015). We had the opportunity to include here some results deriving from the visit in Sicily made by Klaus van de Weyer in March 2018. Roman Romanov identified some specimens and revised some identifications. Data for Sicily are basically limited to more than one hundred years old reports; data for the national Flora have been completed with recent reports for Sardinia (cf. the work made by Ralf Becker…
22nd Meeting of the Group of European Charophytologists (GEC), Palermo, Italy 17-21 September 2018, Programme & Abstracts
2018
Pre-Linnaean illustrations as original material of Linnaean Chara names (Characeae)
2018
Wood (1960) investigated about the types of the four names of Characeae published by Linnaeus (1753) in his Species Plantarum. He focussed on the herbarium specimens forgetting the images mentioned in the protologues. Here we list and present the pre-Linnaean illustrations that have to be considered “original material” (according to the International Code of Nomenclature) for the mentioned names. Chara tomentosa L. - Wood (1960) defined the specimen 1088.1 in the herbarium LINN as “holotype”, actually it is a lectotype (as well reported in The Linnaean Plant Name Typification Project, http://www.nhm.ac.uk/ our-science/data/linnaean-typification) because of the two different figures cited in…
Charophytes for description and monitoring of inland waters in Sicily
2017
The island of Sicily, in the center of the Mediterranean basin, is a well-known biodiversity hotspot (Médail & Quézel, 1997). Unfortunately, the knowledge of its charophyte flora is absolutely unsatisfactory. The few available data derive from some scattered phytosociological works and some articles published more than 100 years ago. According to the last national synthesis (Bazzichelli & Abdelahad, 2009) a total of 19 Charophytes species should occur in the island, distributed in 4 genera: Chara L. (11), Nitella Agardh (5), Tolypella (A. Braun) A. Braun (2) and Lamprothamnium J. Groves (1). However an updated list of the species occurring in the island, together with their distribu…
Combination of linear and nonlinear multivariate approaches effectively uncover responses of phytoplankton communities to environmental changes at re…
2022
The response of a community to environmental changes is either linear or non-linear, so that they can be investigated approximately by linear or nonlinear models. At community level, redundancy analysis (RDA) and canonical correspondence analysis (CCA), and Mantel test and Generalized Dissimilarity Modelling (GDM) are two pairs of fundamental multivariate approaches. Thus, it is necessary to determine how they are used for a given group of communities or a metacommunity. In the present study, we explored the applications of the two pairs of commonly used multivariate methods for the analysis of tropical phytoplankton communities. Phytoplankton were collected from 60 tropical reservoirs in s…
Taxonomic Identity, Geographic Distribution, and Commercial Exploitation of the Culinary-Medicinal Mushroom Pleurotus nebrodensis (Basidiomycetes)
2016
An updated overview of the outcome of studies conducted on the culinary-medicinal mushroom Pleurotus nebrodensis is presented by placing emphasis on the clarification of the taxonomic identity of P. nebrodensis and other related taxa possessing entirely white to cream basidiomes, which grow in association with different plants of the family Apiaceae. Cultivation techniques, quality of the product sold and sales price, as well as nutritional and medicinal aspects are discussed. Taking also into consideration the high economic importance of P. nebrodensis, it is essential to proceed with the verification of the commercial strains currently available in the international market under the name …
Enhancer blocking activity located near the 3′ end of the sea urchin early H2A histone gene
1997
The sea urchin early histone repeating unit contains one copy of each of the five histone genes whose coordinate expression during development is regulated by gene-specific elements. To learn how within the histone repeating unit a gene-specific activator can be prevented to communicate with the heterologous promoters, we searched for domain boundaries by using the enhancer blocking assay. We focused on the region near the 3′ end of the H2A gene where stage-specific nuclease cleavage sites appear upon silencing of the early histone genes. We demonstrated that a DNA fragment of 265 bp in length, defined as sns (for silencing nucleoprotein structure), blocked the enhancer activity of the H2A…