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Viola sect. Melanium, the so-called pansy, is an allopolyploid morphologically well-defined lineage of ca. 110 perennial and annual species in the northern hemisphere, characterized by markedly complex genomic configurations. Five annual pansies occur in Italy, four of which are morphologically very similar and belong to the informal 'V. tricolor species complex': V. arvensis (2n = 34), V. hymettia (2n = 16), V. kitaibeliana (2n = 16), and V. tricolor (2n = 26). Their field recognition is difficult and reflects a long-debated taxonomy often resulting in doubtful records in field inventories and across European herbaria. The current lack of comprehensive intra- and interspecific comparative studies and a relative scarcity of appropriate genetic markers coupled with unambiguous cytological descriptions are hindering clear taxa circumscription and phylogenetic inferences within this group. In this work, we tested DNA sequence variation of three highly variable plastid markers and High-Throughput Sequencing (HTS) of the nuclear ribosomal 5S-IGS region in an attempt to decipher species identity within the V. tricolor species complex and to obtain an insight on their genome organization and evolution. Our results document the close relationships within this species group, a reliable molecular resolution for V. tricolor, and the common ancestry of V. arvensis and the poorly differentiated V. kitaibeliana and V. hymettia. Evidence of an important inter-population geographical divergence was recorded in V. tricolor and V. arvensis, pointing at the existence of different eco-cytotypes within these entities. Overall diversity patterns and the occurrence of two to four differently diverging 5S-IGS lineages are discussed in the light of the acknowledged taxonomy and genomic evolutive trajectories of sect. Melanium. [ABSTRACT FROM AUTHOR]

The assessment of the ecosystem state is fundamental to understand the success of ecological rehabilitation, especially in the long term. We aim to evaluate the rehabilitation success of a unique Mediterranean dune system site along the Tyrrhenian coast of Italy which underwent a dune consolidation intervention and species planting at the beginning of the twentieth century after the destruction of the natural ecosystem. We used three nearby non‐rehabilitated protected coastal sites with different degrees of disturbance as reference sites encompassing different potential rehabilitation outcomes of the target site. To assess the overall result of the intervention, we used several plant characteristics and measured taxonomic and functional beta‐diversity between all sites. We compared the proportions of typical and ruderal species of dune habitat types across sites. We further used the species–area relationship to examine if the number of observed species in our sites differed from the expected. Our analyses revealed that the rehabilitated site was taxonomically and functionally more similar to the least disturbed site. We suggest that plant characteristics arising from botanical inventories can be fruitfully used in rehabilitation assessment as they value the taxonomic and functional species diversity at the community scale. We conclude that plant characteristics compared across sites are useful tools in ecosystem state assessment if they reflect the ecological functions and conservation values of the natural ecosystems. [ABSTRACT FROM AUTHOR]

This integrated study provides new insights into pollen and seed morphology and pollen heteromorphism of four closely related annual taxa of Viola sect. Melanium. The plant material, both fresh and dried, was collected in Italy and studied using light and scanning electron microscope. Palynological data for V. hymettia together with a detailed comparative analysis of seed morphology and micromorphology of the four species are reported for the first time. Results of this work highlight some pollen and seed features as useful diagnostic characters. The pollen size proves to be of diagnostic value to easily separate V. kitaibeliana, having the smallest pollen grains, from the others, especially from V. arvensis with the largest ones. Exine ornamentation is microreticulate, showing no relevant differences among species. We can partially confirm the diagnostic value of the prevailing pollen morph as it can be useful only for V. arvensis (five-aperturate) versus V. tricolor and V. hymettia (four-aperturate). The macro- and micromorphology of seeds provide additional useful distinguishing characters. Particularly, seed size was found to be a good delimitating character, especially to distinguish V. kitaibeliana (with the smallest seeds) from V. arvensis, and easy to be measured with no need of particular equipment. [ABSTRACT FROM AUTHOR]

Aim As a consequence of multiple cycles of deforestation and reforestation, most forest landscapes in Europe consist of a complex mosaic of patches of different successional ages. Despite the biogeographical distinctiveness of the Mediterranean region, studies on the effects of forest age on plant species diversity and composition are almost lacking for this area. This paper evaluates the influence of forest successional age on plant species richness and composition in various forest types of Mediterranean Italy. Location The Natura 2000 network of Siena Province, Tuscany, Italy. Methods Occurrence data on vascular plant species in 208 forest plots were obtained from a larger data set sampled with a stratified random design. The forest successional age of each plot was quantified through a series of historical maps. Species richness and composition were related to the age of the forest by means of GIS techniques and univariate and multivariate statistical analyses. Results Total species richness markedly decreased with increasing successional age due to a significant decrease in the richness of open-habitat species which was not matched by increasing richness of mature forest species. Successional age was the key factor in controlling species richness, while local environmental properties emerged as the main factors shaping community composition. The different forest types showed different temporal trends of species richness and composition and different hierarchies of explanatory factors. Main conclusions Forest successional age emerged as an important factor affecting both species richness and composition, even within the same forest type. Thus, the classification and prioritization of Mediterranean forests exclusively based on present physiognomy or environmental variables causes loss of information about species richness and composition; this could be detrimental for biodiversity conservation. [ABSTRACT FROM AUTHOR]

The article presents the study of Germplasm Bank of Tuscia Botanic Garden and Herbarium Tuscia University, Viterbo-Italy (UTV) on the conservation of pteridophytes such as Osmunda regalis or Royal Fern. The study uses exsiccata from localities within the National Park of Tuscan Archipelago while spores for control tests were from a population within Monterano Regional Nature Reserve. It says that spores collected from exsiccata has low germination compared to the control germination percentage.

The high morphological variability of Viola arvensis may hinder the proper identification of the closely related species with an implication for biodiversity surveys. Variation in floral and vegetative morphology was explored in V. arvensis, compared to V. kitaibeliana, based upon 14 wild Italian populations, to provide new insights into their diagnostic features. Species were characterized using 32 morphological descriptors assessed on 272 flowers and as many leaves and scored as quantitative and categorical variables. Statistical methods, including Linear Discriminant Analysis (LDA), were applied to test species delimitation. Data highlighted variations in sepal size, petal size, leaves shape, stylar dark spot, and pollen magazine higher within V. arvensis than between V. arvensis and V. kitaibeliana. LDA partitioned the V. arvensis samples into two distinct clusters; no clear distinction was found between the cluster combining individuals from grasslands and V. kitaibeliana. The separation of V. arvensis and V. kitaibeliana from V. tricolor, included as a reference, was noticeable. Correlations were found in all species between the flower/leaf position on the stem and some floral and vegetative features. The shape and margin of the lower sepal, the stylar flap, and the lamina margin and apex were diagnostic in field identification. The results support the recognition of an undescribed V. arvensis eco-phenotype linked to seminatural dry grasslands, easily distinguishable from the field-grown type of V. arvensis but hardly distinguishable from the dwarf pansy. Data further corroborate the assumption of general deep-rooted confusion in ascribing poorly developed individuals of V. arvensis to the rare and locally threatened V. kitaibeliana, leading to potential implications for its conservation. [ABSTRACT FROM AUTHOR]

Based on critical examination of both fresh and dried specimens and a morphometric analysis of herbarium specimens we performed a comparative study of the three closely related Gastridium (Poaceae, Tribe: Poeae, Subtribe: Agrostidinae) species G. ventricosum, G. phleoides and G. scabrum collected in Italy. The study aimed to provide new diagnostic tools to improve the taxonomy of the genus and confirm species delimitation. Variation in floral morphology in the three species was explored using seven quantitative and ten qualitative characters measured on 318 spikelets, both awned and unawned. Statistical methods, including principal components analysis (PCA) and non‐metric multidimensional scaling (NMDS), were used. Numerical analyses showed a general distinctness of spikelets and florets, consistent with the three studied species, and revealed among and within species variation patterns in both spikelet types. Accordingly, the most informative quantitative characters appeared to be the width and length of glumes and the length of awns, useful to distinguish G. phleoides which has the narrowest glumes and longer awns than the other species, while G. scabrum has the widest glumes. The most informative qualitative characters appeared to be the presence/absence of thick hairs or minute tubercles on the upper side of the lemma. The autonomy of the three studied species was confirmed. The taxonomic significance of the results is briefly discussed, and notes on the species distribution are included. Some nomenclatural and taxonomic notes on G. scabrum, of which literature still showed evidence of a general unawareness, are provided. [ABSTRACT FROM AUTHOR]

• We compared FQA metrics, Ellenberg values (EIVs), life forms, and chorotypes. • FQAI, EIVs, life forms and chorotypes failed to highlight environmental quality. • Median Coefficients of conservatism (CCs) and Adjusted FQAI were effective. • Median CCs were the best trade-off between effectiveness and simplicity. Vascular plants are good environmental indicators. Thus, floristic inventories have a high potential in environmental management since they reflect the current and past status of the environment. In this study, we used the flora of a suburban riverscape in central Italy to test the performance of the Floristic Quality Assessment (FQA) approach, an expert-based evaluation technique. Ten expert botanists assigned coefficients of conservatism (CC) to 382 plant species. We found statistically significant differences between the values assigned to the inventoried flora by botanical experts. In spite of this, the analysis of pseudo multivariate dissimilarity-based standard errors of CC values assigned by the different experts revealed that, in our case, an assessment by a minimum of five botanists allows characterizing the flora with a stable level of precision. We used the distance from agricultural and urban surfaces as a proxy of anthropogenic disturbance to divide the area around the river in four belts of increasing disturbance. The disturbance gradient was mirrored by median CC values and by the Adjusted Floristic Quality Assessment Index (Adjusted FQAI). Conversely, the Floristic Quality Assessment Index (FQAI), which is based on CC values and on the number of native species, showed increasing values with increasing disturbance. Comparing the performance of median CC values to Ellenberg Indicator Values (EIVs), life forms, and chorotypes, we revealed that the last three indicators may be ineffective in highlighting the conservation status of the environment. We suggest that the use of the median CC values may be a simpler and effective alternative to the calculation of indices in FQA, when the adequacy of the number of experts in minimizing the variability of CC values is a posteriori verified. [ABSTRACT FROM AUTHOR]