Genetic structure in the paleoendemic and endangered Petagnaea gussonei (Spreng.) Rauschert (Saniculoideae, Apiaceae) and implications for its conservation
Our investigation aims to understand the genetic structure and evolutionary history of Petagnaea gussonei, an ancient and endangered species belonging to the Saniculoideae subfamily (Apiaceae). It is paleoendemic to Sicily, with a small number of populations in the Nebrodi Mountains. A total of seven chloroplast microsatellite repeat loci and 12 AFLP primer combinations were used to screen 115 individuals corresponding to 17 populations. The ratio of seed to pollen flow was also calculated using the modified Ennos equation. A relatively high level of genetic diversity was detected with AFLPs (e.g., 0.045 < H < 0.278), and a moderate variation was also found using cpSSRs (0 < Hk < 0.667). Tw…
A further analysis of secretory structures of some taxa belonging to the genus Hypericum (Clusiaceae) in relation to the leaf vascular pattern
This work extends knowledge about the distribution of secretory structures (black nodules, translucent glands, and type A and B secretory canals) to other species of the genus Hypericum L., as only H. perforatum L. appears to have been widely investigated. Moreover, the current study was extended to include leaf vascular patterns. In the species studied, a possible correlation between the presence of black nodules and a particular biological form, that of hemicryptophytes scapose perennials such as H. perfoliatum L., H. perforatum L., H. pubescens Boiss., H. tetrapterum Fr., and H. triquetrifolium Turra, was noted. These black nodules are not present in H. androsaemum L. and H. hircinum L.,…
Multivariate analysis of sites using water invertebrates and land use as indicators of the quality of biotopes of Mediterranean relic plant (Petagnaea gussonei, Apiaceae)
Petagnaea gussonei is a rhizomatous, perennial scapose hemicryptophyte species belonging to a monospecific genus of Apiaceae. It lives only along woodland rivulets and is a Tertiary relic localized in the restricted area of the Nebrodi Mountains (NE Sicily, Italy). Ecological indicators have been employed to understand the status of eight localities (intermittent rivulets) where the species occurs. In order to evaluate both the rivulets' water-quality and landscape use, index of anthropisation (Ia), water fleas bioassay (TU), and analyses of water macroinvertebrates have been employed. The results obtained for the level of toxicity exclude the presence of macropollutants (TU < 0.001), where…
Composition of the essenthial oil of Petagnaea gussonei (Sprengel) Rauschert, a relict species from Sicily (Southern Italy).
The essential oil from leaves, stems and roots of Petagnaea gussonei (Sprengel) Rauschert ( = Petagnia saniculifolia Guss.), endemic to the Nebrodi Mountains (Sicily, Italy), has been analysed by the gas chromatography–mass spectrometry (GC–MS) system on two fused-silica capillary columns of different polarities. A total of 94 components were identified. Quantitative and qualitative differences were found among the analysed parts. The principal compounds from the leaves oil were found to be (w/w%) germacrene D (19.9%), γ-muurolene (7.96%) and caryophyllene oxide (6.85%), while in the oil from stems hexadecanoic acid (23.40%), germacrene D (18.50%) and (Z,Z)-9,12-octadecadienoic acid (13.20%…
Leaf and stem anatomy in eight Hypericum species (Clusiaceae).
Abstract - Foliar micromorphology, epicuticular wax morphology and anatomical features of leaves and stem, particularly secondary xylem, were examined with light microscopy, general and histochemical staining and scanning electron microscopy in eight Hypericum species. Outer tegument tissue and type of secondary xylem are determining characteristics. Secondary xylem is ring-porous in H. perforatum, H. perfoliatum, H. tetrapterum, H. triquetrifolium, H. androsaemum and H. hircinum. In H. aegypticum and H. pubescens xylem is diffuse-porous, which is considered to be a more primitive type. These characteristics may be considered an additional criterion for species identification.
What do leaf anatomy and micromorphology tell us about the psammophilous Pancratium maritimum (Amaryllidaceae) in response to sand dune conditions?
Abstract The present study aimed at verifying the morphological variation in leaf traits among different populations of Pancratium maritimum (sea daffodil) and the correlation between leaf diversity and climate conditions at different sites. Eleven populations of P. maritimum from Mediterranean coastal sand dunes were investigated with respect to leaf surface micro-morphology, leaf anatomy, and vascular pattern. Morphometric analysis was based on 29 quantitative foliar parameters. One-way analysis of variance (ANOVA), principal component analysis (PCA), discriminant function analysis (DFA), and clustering by Ward’s method were used for the statistical evaluation. Results revealed a rather u…
A contribution to the characterization of Ruppia drepanensis (Ruppiaceae), a key species of threatened Mediterranean wetlands
To elucidate the taxonomic status of Ruppia drepanensis Tineo ex Guss. (Alismatales, Ruppiaceae), we performed morphological analysis and DNA barcoding of historical materials (including the lectotype) and fresh samples (including those from a recently discovered population near the locus classicus in Sicily, Italy). We conclude that R. drepanensis is a separate species, closely related to R. spiralis L. ex Dumort., that occurs in temporary inland waters from the western to central sectors of the Mediterranean region. We also highlight the importance of vouchers and the need to link molecular investigations to field, ecological, and morphological investigations.
Phylogenetic and biogeographical inferences for Pancratium (Amaryllidaceae), with an emphasis on the Mediterranean species based on plastid sequence data
The phylogenetics and biogeography of Pancratium (Amaryllidaceae) were investigated, with a focus on the Mediterranean and adjacent areas, with the aim of contributing new information towards a better understanding of the evolutionary history of the genus and the taxonomic placement of P. linosae and P. hirtum. To address these questions, we sequenced four plastid DNA markers: the ndhF and rbcL genes, the trnL(UAA)-trnF(GAA) intergenic spacer and the trnL(UAA) intron, analysing them using parsimony, likelihood and Bayesian approaches. The results show that the relationships among the majority of the species are resolved; however, the relationships of one of the major clades of the genus are…