Checklist of Ornamental Trees, Shrubs, and Succulents of Apulia (Southern Italy).

In this study we focused on the need to fill a knowledge gap among Italian botanical studies namely that of ornamental species census. In particular, we addressed one of the regions in southern Italy with less knowledge in the field of such studies and with an obvious presence of non-native species. A widespread census of the Apulian territory was carried out between 2021 and 2024 in both urban and suburban areas including street trees, parks, and private and historic gardens. The inventory of ornamental trees, shrubs, and succulents of Apulia (southern Italy) was carried out in six provinces, i.e., Bari, Barletta-Andria-Trani, Brindisi, Foggia, Lecce, and Taranto. The checklist comprises 287 taxa (including 265 species, 6 varieties, 5 subspecies, and 11 forms) included in 179 genera belonging to 78 families. We evaluated the number of taxa per families and genera, the presence of each taxa in the provinces of Apulia, the number of taxa per occurrence status, growth forms, geographical origin, and the number of native and alien taxa and also the artificial hybrids. Remarks of the most significant taxa and evaluation of geographical distribution in Italy were also taken into consideration. A large number of surveyed taxa (51.74%) are comprised in the list reported in the recent study on allochthonous vascular flora in Italy with a marked prevalence of Neophyte Casual Alien and Neophyte Naturalized Alien species.

Beyond the Scent: New Evidence about Micromorphological, Phytochemical and Biological Features of Plumeria rubra 'Tonda Palermitana' (Apocynaceae).

Plumeria rubra L. is an ornamental Caribbean plant widely known for its ethnobotanical uses and pharmacological activities. The 'Tonda Palermitana' cultivar, on which no data are to date available, is commonly cultivated in Sicily. The aim of our study was to characterize the micro-morphological features of leaves and flowers of this cultivar by light and Scanning Electron Microscopy and to investigate the phytochemical profile and the biological properties of their food-grade extracts (LE and FE, respectively) by LC-DAD-ESI-MS analysis and different in vitro assays. Numerous branched laticifers were observed, and their secretion contained alkaloids and lipophilic compounds as confirmed by histological analyses. Phytochemical analyses showed the presence of alkaloids (9%), terpenoids (13%) and fatty acids (6%), together with a very abundant presence of iridoids (28%) and polyphenols (39%). The most notable biological activity of both extracts appears to be the antioxidant one, showing half-inhibitory concentrations (IC50) about 5 times lower than those detected in anti-inflammatory assays (383.74 ± 5.65 and 232.05 ± 2.87 vs. 1981.23 ± 12.82 and 1215.13 ± 10.15, for FE and LE, respectively), with LE showing the best, and statistically significant (p < 0.001), biological activity. These results allow us to speculate promising nutraceutical and cosmeceutical applications for this old Sicilian cultivar.

Main Poisonous and Allergenic Plant Species in Sicilian Gardens and Parks: Applications and Recommendations for Use.

This study identified the most common poisonous and allergenic plants occurring in Sicilian gardens and parks. Based on a survey conducted at 100 sites, a list was drawn up that reports the main biological and toxicological characteristics and ornamental uses of these plants. A total of 137 taxa were recorded, of which 108 were poisonous and 32 were allergenic. The most represented families were the Solanaceae, Moraceae, Apocynaceae and Fabaceae. The most represented geographical contingents were the European and the Mediterranean. A large number of toxic and allergenic plants recorded in Sicilian parks and gardens cause gastrointestinal disorders, 21 of which are deadly poisonous. Based on the results, actions for the management of existing gardens and the construction of new ones are discussed. The importance of environmental education for the population starting from school age is stressed. These recommendations aim to preserve cultivated biodiversity and, at the same time, protect human and pet health.

New Alien Plant Taxa for Italy and Europe: An Update.

Despite the wide amount of scientific contributions published on alien plant species, their diffusion dynamics, and their interactions with native taxa, it is increasingly difficult to slow down their spreading and their negative impact on habitats. Last recent years, in fact, a sharp rise in the number of new alien plant taxa introduced in Italy and Europe has been recorded. The aim of this work is to investigate most of the Italian territory in order to verify whether this alarming trend is still underway. Specimen collections and/or observations of alien plants have been performed in as many as 12 Italian regions. All the collected specimens are stored in public or private herbaria. Taxa have been identified according to the literature from the countries of origin of the investigated taxa, while the nomenclature followed the current international references. Updates on 106 taxa are reported. In particular, among 117 new records, 89 are first records, 27 are changes to status and there is 1 extinction. Seven new taxa for Italian alien flora are reported, two of which are new to Europe. The administrative regions with the highest number of records are Calabria (48), Sardegna (17) and Sicilia (15). Five of the surveyed taxa, for the first time, have been considered invasive aliens to Italian territory. The unfrequent amount of original results provided by this work, over the simple importance of data itself, proves how floristic investigation, still today, represents one of the most effective tools in broadening the current knowledge about alien taxa and their dynamics.

Seed germination and vegetative and in vitro propagation of Hieracium lucidum subsp. lucidum (Asteraceae), a critically endangered endemic taxon of the Sicilian flora.

Hieracium lucidum subsp. lucidum is a critically endangered endemic taxa of the Sicilian flora. It is a relict of the Tertiary period surviving on the cliffs of Monte Gallo (NW-Sicily). This research focused on finding the best protocols for seed germination and vegetative and in vitro propagation to contribute to ex situ conservation. Seed germination tests were carried out using constant temperatures of 15 °C, 20 °C and 25 °C in continuous darkness and an alternating temperature of 30/15 °C (16 h/8 h, light/dark). The seeds had no dormancy, and a high germination capacity (70-95%) was obtained at all tested thermoperiods. The possibility of vegetative propagation of the taxon was evaluated through the rooting capacity of stem cuttings treated or not treated with indole-3-butyric acid (IBA). All cuttings were treated with IBA rooted within 2 months, while only 50% of the untreated cuttings were rooted within a longer time. An efficient protocol for rapid in vitro propagation from leaf portions was developed. The response of explants was tested on hormone-free Murashige and Skoog (MS) basal medium and MS enriched with different types of cytokinins: 6-Benzylaminopurine (BAP) and meta-Topolin (mT) in combination with naphthaleneacetic acid (NAA) and 2,4-Dichlorophenoxyacetic acid (2,4-D) at the same concentration. The combination of mT (2 mg L-1) and 2,4-D (1 mg L-1) in the medium was the most effective and showed the highest percentage of callus induction and the mean number of regenerated shoots. The maximum rate of root regeneration and the maximum number and length of roots were obtained on hormone-free MS and MS enriched with IBA at concentrations of 1 mg L-1. From the results obtained, it can be concluded that H. lucidum subsp. lucidum can be successfully propagated using one of the tested techniques, subject to the availability of the material for reproduction.

The Influence of Pedo-Climatic Conditions on the Micromorphological, Phytochemical Features, and Biological Properties of Leaves of Saponaria sicula Raf.

Saponaria sicula Raf. grows in Sicily, Sardinia, and Algeria on limestone cliffs and volcanic sands 1300-2500 m above sea level. The aim of the present study was to investigate how the pedo-climatic conditions influence the micromorphological, phytochemical, and biological properties of Sicilian S. sicula leaves collected in the Madonie Mountains (SsM) and on Etna Mt (SsE). Micromorphological investigations revealed that leaves from SsM had a higher amount of calcium oxalate druses in the mesophyll and a more intense blue-green staining with Toluidine blue O, indicating a higher content of polyphenols. These data were confirmed by phytochemical analyses carried out on hydroalcoholic extracts, which showed a higher content of total phenols (8.56 ± 0.57 g GAE/100 g DE) and flavonoids (6.09 ± 0.17 g RE/100 g DE) in SsM. Sixty-four compounds were identified by LC-DAD-ESI-MS analysis with propelargonidin dimer as the most abundant compound (10.49% and 10.19% in SsM and SsE, respectively). The higher polyphenol content of SsM leaves matches also with their biological activity, identifying SsM extract as the strongest plant complex (IC50 2.75-477.30 µg/mL). In conclusion, the present study experimentally demonstrates that not only climatic differences but also soil characteristics affect the micromorphological, phytochemical, and biological features of this plant species.

Micropropagation of Endemic Endangered Taxa of the Italian Flora: Adenostyles alpina subsp. macrocephala (Asteraceae), as a Case Study.

The conservation of endangered, rare, and endemic plant species is based on in situ and ex situ conservation strategies. When in situ conservation alone is not sufficient to guarantee the survival of the species, ex situ techniques are adopted in support. This study aimed to develop an efficient micropropagation protocol for Adenostyles by evaluating the effect of different plant growth regulators on leaf explants. Adenostyles alpina subsp. macrocephala (Asterace) is a perennial herbaceous plant endemic to Calabria (Southern Italy). The genus Adenostyles includes three species confined to the mountains of the Mediterranean and southern Europe. For callus induction, media supplemented with different concentrations of Benzylaminopurine (BAP) (0.5, 1, 2, and 3 mg L-1), Naphthaleneacetic Acid (NAA) (1 mg L-1), and 2,4-Dichlorophenoxyacetic Acid (2,4-D) (1 mg L-1) were tested. Shoot regeneration and proliferation were obtained in media supplemented with BAP (1, 2, and 3 mg L-1) and NAA (1 mg L-1). Root induction was obtained in media supplemented with IBA (0.25, 0.50, and 1 mg L-1) and NAA (0.25, 0.50, and 1 mg L-1). Statistically significant differences in callus induction and shoot regeneration were observed between the various media tested. The medium containing Murashige and Skoog (MS) supplemented with 3 mg L-1 of BAP and 1 mg L-1 of NAA showed the highest percentage of callus induction and increased shoot regeneration. The regenerated shoots showed more effective root induction in the hormone-free MS medium and in the presence of Indole-3-Butyric Acid (IBA) at concentrations of 0.25, 0.50, and 1 mg L-1. These results can be used as a basis for the preparation of a micropropagation protocol for different taxa of Adenostyles, as well as other species of Asteraceae specialized to the Mediterranean mountain habitat.

A new species within the Centaureabusambarensis complex (Asteraceae, Cardueae) from Sicily.

Background: The Centaureabusambarensis group is made up by eight species endemic to Sicily. We statistically evaluated a population found on the Nebrodi Mountain (NE Sicily) to verify if the observed morphological differences with the already known taxa justified the description of a new one. It resulted in being sufficiently distinct to deserve recognition at the species level. New information: Centaureavaldemonensis, a new species endemic to Sicily is described and illustrated here. It is confined to the Nebrodi Mountains (NE Sicily). The distinction of this taxon from the others belonging to the C.busambarensis complex has been supported with the aid of statistical analyses on morphological characters. The differences with the related taxa are discussed.

Pharmacognostic approach to evaluate the micromorphological, phytochemical and biological features of Citrus lumia seeds.

This study evaluated the micro-morphology as well as the chemical and biological features of Citrus lumia seeds. The cream-colored pyriform seed showed a woody coat covered by a thick layer of mucilage and an embryo with two large cotyledons rich in oil bodies. Hydroxycinnamic acid glycosides and flavonoids are the most abundant compounds in methanol and ethyl acetate extracts (ME and EAE), respectively. Conversely, fatty acids and α-tocopherol represent the main bioactive compounds in the hexane extract (HE). ME showed the most promising antioxidant and anti-inflammatory activities already in cell-free assays. These results were confirmed by experiments carried out on human primary cells. Indeed, ME showed the best inhibitory activity against heat-induced haemolysis and ROS formation in erythrocytes. Moreover, the same order of potency (ME > EAE > HE) was observed also on peripheral blood mononuclear cells, in which the seed extracts were able to decrease TNF-α and IL-6 release after LPS-induced inflammation.

Comparison of different methods to assess the distribution of alien plants along the road network and use of Google Street View panoramas interpretation in Sicily (Italy) as a case study.

The survey by foot in the field is compared to the survey from a car, the photo-interpretation of Google Street View (GSV) panoramas continuously and at intervals of 1.5 km and the photo-interpretation of Google Earth aerial images on a 10 km stretch of road in Sicily. The survey by foot was used as reference for the other methods. The interpretation of continuous GSV panoramas gave similar results as the assessment by car in terms of the number of species identified and their location, but with lower cost. The interpretation online of aerial photos allowed the identification of a limited number of taxa, but gave a good localisation for them. Interpretation of GSV panoramas, each of 1.5 km, allowed the recognition of twice as many taxa as the interpretation of aerial photos and taking half the time, but did not allow a complete localisation. None of these methods alone seems sufficient to carry out a complete survey. A mixture of different techniques, which may vary according to the available resources and the goal to be achieved, seems to be the best compromise. To further test the capabilities of the survey using the interpretation of GSV panoramas every 1.5 km along the roads, we proceeded to study the alien plants along 3500 km of the road network on the island of Sicily. This survey identified only 10% of the known species for the region, but allowed us to trace the distribution of invasive species whose distribution is currently poorly recorded.