Osservazioni sulle strategie riproduttive dei taxa appartenenti al gruppo di Limonium articulatum (Plumbaginaceae)

Limonium articulatum (Plumbaginaceae) e le specie affini costituiscono un gruppo tassonomico riconosciuto da diversi autori che si rinviene lungo le coste della Corsica, Sardegna e dell’Arcipelago Toscano. In concomitanza con indagini morfometriche, sono state condotte osservazioni sulla biologia riproduttiva di queste specie su materiale d’erbario. Nelle specie a più ampia distribuzione, L. articulatum e L. contortirameum, si sono osservate solo combinazioni autoincompatibili. Lo stesso in L. caprarie, L. corsicum, L. strictissimum e L. tarcoense. In L. coralliforme, L. dolcheri, L. florentinum, L. tibulatium e L. ursanum sono state osservate combinazioni autofertili. Non si sono verificati casi di combinazioni autofertili e combinazioni auto-incompatibili nello stesso taxon

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) presenti in Italia meridionale. In particolare, per le 12 popolazioni campionate, sono state condotte analisi morfometriche su 29 caratteri divisi in 21 quantitativi continui, 5 quantitativi discreti e 3 qualitativi e sono state analizzati i rapporti filogenetici utilizzando 2 marcatori nucleari (nrITS e nrETS) e un marcatore plastidiale (ndhF-rpl32). Inoltre il presente studio, si propone di chiarire l’esatta consistenza dell’unica popolazione di A. alpina subsp. nebrodensis, taxon endemico puntiforme delle Madonie (Sicilia), il monitoraggio in campo e la ricerca di ulteriori popolamenti all’interno del territorio madonita e nel restante territorio Siciliano. I risultati ottenuti hanno permesso di confermare che A. alpina subsp. nebrodensis, è fortemente a rischio di estinzione essendo ad oggi, conosciuto un unico individuo. Inoltre, è stato possibile estendere l’areale di A. alpina subsp. macrocephala, ritenuta finora esclusiva dell’Aspromonte, anche alla Sila ed escludere la presenza A. alpina subsp. alpina e di A. alliariae in Italia meridionale e tutte le segnalazioni precedenti di questi taxa sono da riferire ad A. australis, endemica dell’Italia meridionale. Infine viene ridefinito lo status di A. australis, considerando come sottospecie di A. alpina e sono state costruite chiavi dicotomiche per il riconoscimento dei taxa del gruppo di A. alpina, realizzando per ognuno di essi una scheda descrittiva.Adenostyles Cass., is a genus endemic to Europe belonging to the tribe Senecioneae and to the “group quadridentate” with Caucasalia B. Nord., Dolichorrhiza (Pojark.) Galushko, Iranecio B. Nord. and Pojarkovia Askerova. It is distributed in the whole Alpine territory but its distribution extends also to N Spain, Corse (France) and along the whole Apennine chain in Italy until Calabria and Sicily, in the Balkans and, dubitatively, in Greece. In this study the results of taxonomic studies done on the taxa belonging to the group of Adenostyles alpina (Asteraceae) occurring in S Italy are presented. In particular, for the 12 surveyed populations, morphologic analyses on 29 characters (21 quantitative continuous, 5 quantitative discrete and 3 qualitative) and their phylogenetic relations have been analysed using 2 nuclear (nrITS and nrETS) and a plastidial marker (ndhF-rpl32). In addition this study aims to survey the single known population of A. alpina subsp. nebrodensis, punctual endemic to the Madonie, in Sicily, and to search in the field further populations in the Madonie and in the rest of Sicily. The results obtained confirmed that A. alpina subsp. nebrodensis is critically endangered due to the fact that a single individual still exists. It has been possible to extend the distribution range of A. alpina subsp. macrocephala, up to now considered exclusive to Aspromonte, to Sila and to exclude the occurrence of A. alpina subsp. alpina and of A. alliariae in S Italy and refer their previous records to A. australis, endemic to S Italy. Finally, the taxonomic status of A. australis is reconsidered as subspecies of A. alpina and new dichotomous key have been realized for the identification of the taxa belonging to the A. alpina group. A descriptive form for each of the considered taxa is proposed

A new species of Isatis (Brassicaceae) from the Pollino National Park (Basilicata, S Italy)

A new species, Isatis raimondoi (Brassicaceae) is described from Mt Alpi in the Pollino National Park (Basilicata, Southern Italy). Its relationships with the other species of Isatis occurring in Italy are examined

First record of Euphorbia graminea (Euphorbiaceae) in Italy

Euphorbia graminea Jacq. (Euphorbiaceae), a species native from Central America through northern South America, from Northern Mexico to Peru, has been found naturalized near Palermo (Sicily). This is the first record for Italy and Europ

ANALISI DELLO STATO TENSIONALE IN RESINE EPOSSIDICHE SOTTOPOSTE AD INVECCHIAMENTO IDROTERMICO MEDIANTE TECNICA FOTOELASTICA

In questo lavoro si è analizzato lo stato tensionale che nasce in sistemi epossidici DGEBA quando sono sottoposti ad invecchiamento idro-termico, tramite la tecnica fotoelastica a trasmissione, basata sul metodo a variazione di fase di Compensazione di Tardy. I provini, monitorati ad intervalli di tempo regolari durante i processi di assorbimento e desorbimento di acqua, sono stati osservati al polariscopio circolare. La tecnica ha permesso di analizzare, sia qualitativamente, sia quantitativamente, lo stato tensionale indotto dal non uniforme “swelling” durante l’intero processo di invecchiamento. Inoltre, lo studio ha analizzato anche provini criccati di tipo Single Edge Notched Bending; l’analisi fotoelastica ha evidenziato come all’apice della cricca si crea un sistema di frange fotoelastiche peculiari, influenzato dalla presenza della singolarit

Water diffusion and swelling stresses in highly crosslinked epoxy matrices

The present work investigates the swelling induced stresses arising in two epoxy systems during water uptake. The analysed systems are two epoxy resin based on DGEBA monomer and DGEBF monomer respectively, both fully cured by DDS amine. The systems achieve different cross-link density degrees, and are characterised by high glass transition temperatures ranging between 200 and 230 °C. Both epoxies have been conditioned in deionized water baths at two different temperatures (50 °C and 80 °C). A desorption process at room temperature in a dry airborne environment was performed after saturation. Dynamic Mechanical Thermal Analysis, carried out at the various stages of hydrothermal conditioning, has allowed to characterise the modifications occurring in the network structures during aging. Photoelastic Stress Analysis is adopted to monitor the evolution of stresses on rectangular beam samples during absorption and desorption of water. Correlation of water uptake, dynamic mechanical behaviour and transitory stress fields, has allowed to make some assumptions about the influence of the epoxy network on the swelling behaviour

Taxonomic remarks on Isatis tinctoria (Brassicaceae) from Pollino National Park (Basilicata, Italy)

Isatis L. (Brassicaceae) is an Eurasian genus including 79 species (1). It is one of the most difficult cruciferous genera (2). Some species, in fact, are highly polymorphic in fruit morphology, the structures that provide the most diagnostic characters (3). In addition, due to the extreme variability in all morphological characters, the limits of many species are uncertain (4). Most if not all diagnostic characters used in earlier classifications are very variable and because of the unreliability of vegetative and floral characters it is difficult or impossible to identify many specimens when mature fruits are missing (5). The patterns of variation suggest that hybridisation may be widespread (4). Moreover, intermediate specimens are rather frequent, even between some taxa that are morphologically easily recognisable (4). In Italy, according to Conti & al. (6), Isatis is represented by 3 species: I. apennina Grande (= I. allioni P.W.Ball), endemic to Italy and France (south-west Alps and central Apennine), I. praecox Kit., an European taxon restricted to Lombardia, and I. tinctoria L., an Asiatic species widespread in central and south Italy. Floristic investigations in the Pollino National Park (on the Lucanian side) led to the discovery of a little population referable to I. tinctoria. However, a comparative study of the plants showed that they differ in many relevant characters. The fact that this Lucanian population has morphological dissimilarities involves its critical revision that could bring to a new taxonomic delimitation

Notulae to the Italian alien vascular flora 6

In this contribution, new data concerning the distribution of vascular flora alien to Italy are presented. It includes new records, confirmations, exclusions, and status changes for Italy or for Italian administrative regions of taxa in the genera Acalypha, Acer, Canna, Cardamine, Cedrus, Chlorophytum, Citrus, Cyperus, Epilobium, Eucalyptus, Euphorbia, Gamochaeta, Hesperocyparis, Heteranthera, Lemna, Ligustrum, Lycium, Nassella, Nothoscordum, Oenothera, Osteospermum, Paspalum, Pontederia, Romulea, Rudbeckia, Salvia, Sesbania, Setaria, Sicyos, Styphnolobium, Symphyotrichum, and Tradescantia. Nomenclature and distribution updates, published elsewhere, and corrigenda are provided as supplementary material

Notulae to the Italian native vascular flora: 10

In this contribution, new data concerning the distribution of native vascular flora in Italy are presented. It includes new records, confirmations, exclusions, and status changes to the Italian administrative regions for taxa in the genera Artemisia, Chaetonychia, Cirsium, Cynanchum, Genista, Hieracium, Iberis, Melica, Misopates, Myosotis, Thalictrum, Trifolium, Utricularia, Veronica, and Vicia. Nomenclatural and distribution updates, published elsewhere, and corrigenda are provided as supplementary material

Notulae to the Italian native vascular flora: 5.

In this contribution, new data concerning the distribution of native vascular flora in Italy are presented. It includes new records and confirmations to the Italian administrative regions for taxa in the genera Allium, Arabis, Campanula, Centaurea, Chaerophyllum, Crocus, Dactylis, Dianthus, Festuca, Galanthus, Helianthemum, Lysimachia, Milium, Pteris, and Quercus. Nomenclature and distribution updates, published elsewhere, and corrections are provided as supplementary material