Search results for "sistematica"

Variabilità morfologica e ultrastrutturale delle cipsele delle specie siciliane di Helichrysum (Asteraceae)

2014

Si riportano i risultati di uno studio sui caratteri morfologici e ultrastrutturali delle cipsele dei taxa siciliani di Helichrysum e sulla variabilità esistente con lo scopo di valutarne l'uso a fini tassonomici. Campioni di diaspore, relativi a 23 accessioni di 12 diversi taxa, sono stati sottoposti a esame macro-micromorfologico e ultrastrutturale al SEM. I dati sono stati elaborati statisticamente mediante ANOVA e varie analisi multivariate (AFD, ACP, CAG).

WOODIV, a database of occurrences, functional traits, and phylogenetic data for all Euro-Mediterranean trees

2021

Trees play a key role in the structure and function of many ecosystems worldwide. In the Mediterranean Basin, forests cover approximately 22% of the total land area hosting a large number of endemics (46 species). Despite its particularities and vulnerability, the biodiversity of Mediterranean trees is not well known at the taxonomic, spatial, functional, and genetic levels required for conservation applications. The WOODIV database fills this gap by providing reliable occurrences, four functional traits (plant height, seed mass, wood density, and specific leaf area), and sequences from three DNA-regions (rbcL, matK, and trnH-psbA), together with modelled occurrences and a phylogeny for all…

Seeds vitality and fungal contamination in Abies nebrodensis

2022

Seeds of Abies nebrodensis were subjected to laboratory tests aimed to detect fungal contaminants and to obtain xenobiotic-free seedlings, by the use of different surface sterilising agents. Moreover, hot water at 60°C was used to suppress any fungal microorganisms colonizing the inner tissues. Alternaria alternata, Aspergillus flavus and Stemphylium vesicarium were the most frequent fungal contaminants. Non-contaminated seeds showed germination values ranging from 0 to 36.4% depending on the applied sterilization protocol. Further analyses will be carried out to establish the influence of these fungi on the seed germination process and their relationship with seedlings of A. nebrodensis.

Shedding light on typical species: Implications for habitat monitoring

2021

Habitat monitoring in Europe is regulated by Article 17 of the Habitats Directive, which suggests the use of typical species to assess habitat conservation status. Yet, the Directive uses the term “typical” species but does not provide a definition, either for its use in reporting or for its use in impact assessments. To address the issue, an online workshop was organized by the Italian Society for Vegetation Science (SISV) to shed light on the diversity of perspectives regarding the different concepts of typical species, and to discuss the possible implications for habitat monitoring. To this aim, we inquired 73 people with a very different degree of expertise in the field of veget…

Genetic Variability and Taxonomical Considerations about Six Species of European Cardueline Finches (Aves, Passeriformes)

1997

Abstract Electrophoretic patterns of seven enzyme systems and two nonenzymatic proteins, albumin and haemoglobin, representing 13 loci, have been investigated in six species of cardueline finches with Palearctic distribution. A new locus, SOD-3, has been characterized in this subfamily. The two nonenzymatic proteins turned out to be the best genetic markers. From the analysis of the genetic distances it emerges that the mean values between species are higher than those reported for other groups of birds. However, the same results were obtained for other species of the same subfamily native to North America. In both cases this result is probably due to a classification that disagrees with th…

Sustainable gardens: an evaluation tool for management and planning strategies.

2014

An evaluation tool was defined in order to manage gardens considering the six main directives of sustainability, from plant collections to public awareness and fruition.

STUDI TASSONOMICI SU ADENOSTYLES ALPINA (ASTERACEAE) IN ITALIA MERIDIONALE

Adenostyles Cass., è un genere endemico europeo, appartenente alla la tribù delle Senecioneae, e fa parte del cosidetto ‘gruppo Quadridentato’ insieme ai generi Caucasalia B. Nord., Dolichorrhiza (Pojark.) Galushko, Iranecio B. Nord. e Pojarkovia Askerova. Esso è prevalentemente distribuito in tutto il territorio alpino, ma il suo areale si estende anche alla Spagna settentrionale, Corsica (Francia) e lungo tutta la catena appenninica in Italia, comprese le montagne della Calabria e della Sicilia, Balcani e, dubitativamente, in Grecia. Nel presente studio vengono presentati i risultati sugli studi tassonomici effettuati sui taxa appartenenti al gruppo di Adenostyles alpina (Asteraceae) pres…

An inventory of the names of vascular plants endemic to Italy, their loci classici and types

2015

The census of the loci classici of 1,400 Italian endemic vascular plants (i.e. not thriving elsewhere with the exception of Corsica and Malta) is here presented and described. The effective place of publication of accepted names, basionyms and homotypic synonyms were identified and critically verified. This often resulted in some change in authorship attribution and, in seven cases, in validation problems (Asperula cynanchica var. lactea var. nov., A. lactea comb. nov., Biscutella laevigata subsp. raffaelliana subsp. nov., Ferulago nodosa subsp. geniculata comb. & stat. nov., Limonium tineoi comb. nov., L. usticanum sp. nov., Noccaea torreana comb. nov.). The geographic information on t…

Micromorphological approach to the systematics of Mediterranean Isoëtes species (Isoëtaceae, Lycopodiophyta): analysis of the megaspore surface

2012

Megaspore ornamentation is one of the few morphological characters used in the taxonomy of the genus Isoëtes. In the present work, we test the application of this character for distinguishing some Isoëtes species occurring in the Mediterranean: Isoëtes sicula, which according to some authors should be included as a variety in I. histrix, and the recently described I. todaroana, whose affinity with other taxa is currently unknown. Two additional species (I. duriei, I. velata) were also included in the analysis. The megaspores were studied using scanning electron microscopy combined with energy-dispersive X-ray spectroscopy and chemical treatment. In all species, the megaspore surface is cove…

A reassessment of the sections of the genus Cytisus Desf. (Cytiseae, Leguminosae)

2006

Recent morphological and molecular research on Cytisus and allied genera has produced a great deal of new data relevant to systematics, which have not yet been incorporated into a consistent classification system of the genus. We have compared and evaluated recently published cladograms and phenograms based on morphological and molecular (nuclear and plastid DNA) characters. The genus Cytisus sensu lato, including Calicotome, Chamaecytisus, Chronanthus, and Lembotropis, appears to be monophyletic. A subdivision of the genus Cytisus in 13 sections is presented; one species, C. tribracteolatus, remains incertae sedis. A new section (C. sect. Dendrocytisus) and two new combinations for taxa in…