Rapid adaptation of seed germination requirements of the threatened Mediterranean species Malcolmia littorea (Brassicaceae) and implications for its reintroduction

Malcolmia littorea (Brassicaceae) is a threatened species growing in the coastal sandy dunes of the west-Mediterranean basin. In this study, the seed germination and seedling emergence requirements of this species were investigated in the only remaining native population in Italy. The highest germination percentage was achieved in darkness with scoring under safe green light at 5–10 °C. Seedling emergence was highest when seeds were buried between 1 and 10 mm in depth. The results suggest that germination and seedling emergence are adapted to Mediterranean coastal habitats by employing a common mechanism of light-inhibited germination and by germinating at cooler temperatures before the onset of the summer drought. Seeds were also collected from plants cultivated at a botanical garden and from plants reintroduced by sowing or by transplanting. For those populations, germination was maximal between 10–25 °C, suggesting that the thermal germination behaviour may be affected by the maternal environment of seed production within one generation. It is suggested to use seeds produced in the same environment to which they will be used for the reintroduction of this species.     

HYDROGEN SULPHIDE AND EPIPHYTIC LICHEN VEGETATION: A CASE STUDY ON MT. AMIATA (CENTRAL ITALY)

A survey aimed at studying the effects of hydrogen sulphide (H₂S) on epiphytic lichen vegetation was carried out at Acquapassante (Mt. Amiata, Central Italy). In 1992, lichen vegetation was surveyed using a sampling grid of ten units, on 18 chestnut trees along a transect from a chimney emitting H₂S toc. 200 m in the direction of the prevailing winds. A Lichen Biodiversity Index (LBI) was calculated as the sum of the frequencies of all species present within the grid. The same survey was repeated five years later. Concentration Analysis was applied to describe the data structure, and Procrustes Analysis was used to verify the congruence between the ordinations of 1992 and 1997. The statistically significant linear and non-linear regressions found between environmental variables (distance of relevés from the chimney, bark pH, lichen biomass of selected foliose and fruticose species, total sulphur content ofEvernia prunastri,Hypogymnia physodes,Parmelia sulcataandRamalina fastigiata) and the position of the relevé points on the ordination axes suggest that species distribution along the transect is related to differences in H₂S tolerance. However, some crustose species (Lecanoracf.conizaeoides,L. salignaandScoliciosporum umbrinum) should be probably excluded from the computation of the LBI for monitoring purposes, as their optimum is in the immediate vicinity of the H₂S source.     

Genetic structure of expanding wolf (Canis lupus) populations in Italy and Croatia,and the early steps of the recolonization of the Eastern Alps

After centuries of range contraction and demographic declines wolves are now expanding in Europe, colonizing regions from where they have been absent for centuries. Wolf colonizing the western Alps originate by the expansion of the Italian population. Vagrant wolves of Italian and Dinaric-Balkan origins have been recently observed in the Eastern Alps. In this study we compared the genetic structure of wolf populations in Italy and Croatia, aiming to identify the sources of the ongoing recolonization of the Eastern Alps. DNA samples, extracted from 282 Italian and 152 Croatian wolves, were genotyped at 12 autosomal microsatellites (STR), four Y-linked STR and at the hypervariable part of the mitochondrial DNA control-region (mtDNA CR1). Wolves in Croatia and Italy underwent recent demographic bottlenecks, but they differ in genetic diversity and population structure. Wolves in Croatia were more variable at STR loci (N_A = 7.4, H_O = 0.66, H_E = 0.72; n = 152) than wolves in Italy (N_A = 5.3, H_O = 0.57, H_E = 0.58; n = 282). We found four mitochondrial DNA (mtDNA CR1) and 11 Y-STR haplotypes in Croatian wolves, but only one mtDNA CR1 and three Y-STR haplotypes in Italy. Wolves in Croatia were subdivided into three genetically distinct subpopulations (in Dalmatia, Gorski kotar and Lika regions), while Italian wolves were not sub-structured. Assignment testing shows that the eastern and central Alps are recolonized by wolves dispersing from both the Italian and Dinaric populations. The recolonization of the Alps will predictably continue in the future and the new population will be genetically admixed and very variable with greater opportunities for local adaptations and survival.     

Life-history traits and habitat preferences of colonizing plant species in long-term spontaneous succession in abandoned gravel–sand pits

The following question was asked: Species of what traits and ecological demands are the best and the least successful colonizers in the course of succession in disused gravel–sand pits?Abandoned gravel–sand pits (36) were studied in the Czech Republic. Together 224 phytosociological relevés were recorded in 5 m×5 m plots in all available seral stages ranging in age from 1 to 75 years. Complete lists of species occurring in (semi-)natural habitats were surveyed up to a distance of 100 m from each relevé. The colonization success of each species was expressed by an index between 0 and 1 which was obtained as the ratio of the number of relevés with species present in a pit/the number of relevés with the species occurrence in their surroundings. Species characteristics were taken from available databases. Data were elaborated by ordination analysis and regression tree analysis. Generally, the best colonizers of gravel–sand pits were hydrophytes with the ability to vegetatively reproduce. In particular, at the beginning of succession, anemochorous species played the most important role. Stress tolerant species, possessing light diaspores, were typical of nitrogen poor and acidic habitats. Later, sciophilous and nitrophilous species of mesic habitats increased in importance. They have heavier diaspores, and are mostly phanerophytes or geophytes, often with the ability to vegetatively reproduce as well as exhibiting higher demand for pH. Plant functional traits were recognized as powerful tools to predict the colonization success of plants available in the local species pool. They may help predict vegetation succession in various human-disturbed sites and thus be used in various restoration programmes.     

The return of the Iberian wild goat Capra pyrenaica to Portugal: From reintroduction to recolonization

The Iberian wild goat (Capra pyrenaica) is an endemic species of the Iberian Peninsula. Of the four generally accepted subspecies (Capra pyrenaica victoriae, C.p. hispanica, C.p. pyrenaica, C.p. lusitanica) only two subsist (C.p. victoriae, C p. hispanica). The subspecies once found in Portugal, C. p. lusitanica, became extinct in the 19th century. However, the reintroduction of the C. p. victoriae in north-west Spain, led to the natural recolonization of this subspecies into Portugal. Knowledge of the Iberian wild goat in Portugal is still limited, making it difficult to evaluate the major conservation/management needs. To fill this gap, here we describe the historical distribution of the Iberian wild goat in Portugal and summarize the available information on the reintroduction and recolonization process of this species. Additionally, we used line itinerary survey (2011–2012), coupled with Distance Sampling, to estimate current densities, range and population structure of the Iberian wild goat distribution in Portugal. The Iberian wild goat density is 2.78/100 ha (95% CI: 1,72–4,50; CV: 18,36%) and the abundance is of 576 (CI 95%: 356–930; CV: 18,36%). The distribution data shows that the population is divided in three nuclei: 1- Serra do Gerês (13,840 ha); 2–Serra Amarela (1235 ha); 3–Castro Laboreiro (343 ha), in a total area of 15,418 ha. Iberian wild goat population in Portugal has greatly increased in the last years, both in number and distribution range. The demographic data shows a potential for increase in the next years but our current ecological background knowledge still remains limited. Iberian wild goat management will benefit from a long-term project including public awareness, scientific research and management solutions.     

Behavioral and mortality responses of the bivalves Scrobicularia plana and Cerastoderma edule to temperature,as indicator of climate change's potential impacts

Temperature is one of the most important abiotic factors affected by climate change. It determines physiological processes, ecological patterns and establishes the limits of geographic distribution of species. The induced thermal stress frequently results in physiological and behavioral responses and, in extreme cases, may lead to mortality episodes. Scrobicularia plana and Cerastoderma edule behavioral and mortality responses to temperature were evaluated. Specimens were sampled in the Mondego estuary (Portugal), acclimated and exposed to different temperature treatments (5–35 °C). Individual activity and mortality were registered during 120 h laboratory assays. Both species showed a thermal optimum for their activity (S. plana: 15–23 °C; C. edule: 20–23 °C), and survival was mainly affected by high temperature (S. plana: LC50_120 h = 28.86 °C; C. edule: LC50_120 h = 28.01 °C), with 100% mortality above critical values (≥32 °C). Results further indicated that both species are more affected the higher the temperature and the longer the exposure time. This study indicates that the occurrence of extreme climatic events, especially heat waves, may be particularly impairing for these species.     

Does salt stress increase the ability of the exotic legume Acacia longifolia to compete with native legumes in sand dune ecosystems?

Sand dune ecosystems are one of the areas most affected by the introduction of invasive species which represents a threat for biodiversity conservation. Their invasion patterns and spread may depend on their salinity tolerance, besides other factors. To test this hypothesis, we investigated the effects of salt stress on seed germination and on the activity of antioxidant enzymes (catalase, CAT; ascorbate peroxidase, APX; peroxidase, POX; and glutathione reductase, GR) in two legume species, an invasive, Acacia longifolia (Andrews.) Willd., and a native, Ulex europaeus (L.), very common in the sand dunes of the coast of Portugal. Salt stress was induced by adding NaCl at different concentrations, 0, 50, 100 and 200 mM, for 15 days. Results showed that the highest germination percentages were obtained in distilled water (control) and that, with increasing salt concentration, seed germination was delayed and decreased in both species. Inhibition of germination was higher in the native species, only 3% of seeds germinated at 100 mM and no seeds germinated at 200 mM NaCl. In the invasive species, the reduction was higher at 200 mM NaCl (16%). Considering the coefficient of germination velocity, a decrease in both species with increasing NaCl concentration was observed. The CAT and GR activities decreased in A. longifolia with increasing salinity. In turn, APX activity significantly increased as NaCl concentration increased while the POX activities declined at the highest NaCl concentration. On the other hand, at 50 mM NaCl lower activity of CAT and APX and higher GR and POX were found in U. europaeus. In both species, protein content increased as NaCl concentration increased. In addition, it seems that APX activities play an essential role in the scavenging reactive oxygen species (ROS). These results suggest that the seeds of the invasive legume A. longifolia are more tolerant to salinity than the native legume U. europaeus, and seem better equipped to handle the physiological stress of high salinity, which may contribute to its invasive ability in sand dunes.     

The breeding management affects fresh and cryopreserved semen characteristics in Melopsittacus undulatus

Melopsittacus undulatus is a companion parrot worldwide diffused. Many parrots are considered endangered or vulnerable. The preservation of semen is crucial in endangered species, thus, M. undulatus could be a good model to study sperm characteristics and semen cryopreservation in these other endangered parrots. In this study the effect of the breeding management (males bred in promiscuous aviary or in couple) on sperm characteristics (motility, membrane integrity and morphometry) of fresh and cryopreserved semen was evaluated. The computer-assisted sperm analysis (CASA) revealed a significant effect of the husbandry method on semen characteristics in budgerigars: male housed in couple with the female in individual cages allowed the higher results in term of both semen quantity and sperm quality. Total and progressive motility were significantly higher in males bred in couple (68.7 ± 8.9% and 54 ± 15.9%, respectively) than in promiscuous aviary (48.3 ± 15.1% and 24.4 ± 12.4%, respectively), such as sperm velocity (average path velocity, straight line velocity, and curvilinear velocity). The type of sperm movement (amplitude of lateral head displacement, beat cross frequency, straightness, and linearity), sperm membrane integrity and morphometry parameters seemed not affected by the husbandry method. The standardization of a CASA procedure for the semen analysis in M. undulatus allow further studies on parrot semen manipulation and cryopreservation, but the method used for the breeding of the male could have a significant effect on the semen quality.     

Systematics and biogeography of the Neotropical genus Mabuya,with special emphasis on the Amazonian skink Mabuya nigropunctata (Reptilia,Scincidae)

Phylogenetic analyses using up to 1532 base pairs (bp) of mitochondrial DNA from 106 specimens of Neotropical Mabuya, including 18 of the 19 recognized South American and Mesoamerican species, indicate that most species of the genus are monophyletic, including M. nigropunctata that had previously been reported to be paraphyletic. The present results shows that this species includes three highly divergent and largely allopatric lineages restricted to occidental, meridional, and oriental Amazonia. Our dataset demonstrates that previous claims regarding the paraphyletic status of M. nigropunctata and the phylogenetic relationships within this species complex based on the analysis of three mitochondrial and four nuclear genes (approx. 5000 bp) were erroneous and resulted from two contaminated cytochrome b sequences.The phylogenetic results indicate that diversification in the Neotropical genus Mabuya started approximately in the Middle Miocene (15.5–13.4 Ma). The divergence dates estimated for the Mabuya nigropunctata species complex suggest that the major cladogenetic events that produced the three main groups (occidental (oriental + meridional)) occurred during the Late Miocene. These estimations show that diversification within the M. nigropunctata species complex was not triggered by the climatic changes that occurred during the Pleistocene, as has been suggested by several authors. Rather, our data support the hypothesis that the late tertiary (essentially Miocene epoch) was a period that played a very important role in the generation of biological diversity in the Amazonian forests.Speciation between Mabuya carvalhoi, endemic to the coastal mountain range of Venezuela, and M. croizati, restricted to the Guiana Shield, occurred during the Middle Miocene and may have been as the result of a vicariant event produced by the formation of the present day Orinoco river drainage basin and the consequent appearance of the Llanos del Orinoco, which acted as a barrier to dispersal between these two species. The split between M. bistriata and M. altamazonica and between the occidental and (meridional + oriental) clades of M. nigropunctata fits very well with the biogeographic split between the eastern and western Amazon basins reported for several other taxa.     

A phytosociological survey of the Corynephorus canescens (L.) Beauv. communities of Italy

Abstract

In Italy, Corynephorus communities are distributed along the medium course of the Ticino river and Sesia river and the internal sand dunes of Lomellina (through the Vercelli, Novara and Pavia provinces); these stations represent the southern limit of European distribution of this habitat. A phytosociological study was carried out to gain better knowledge of their composition; of their affinity or diversity against the central European communities; of their distribution and of the main threats to their conservation. Original and literature relevés (114) were elaborated producing a cluster analysis; correspondence analysis (CA), principal component analysis and Kruskal–Wallis test were carried on to characterize the clusters of relevés taking into consideration biological forms, chorological groups, Ellenberg indicator values and floristic groups. Italian Corynephorus communities can be attributed to the following syntaxa: Spergulo vernalis-Corynephoretum canescentis, Spergulo vernalis-Corynephoretum canescentis cladonietosum, Spergulo vernalis-Corynephoretum canescentis silenetosum nutantis and Spergulo vernalis-Corynephoretum canescentis artemisietosum campestris. Italian Corynephorus communities are included in the Habitat 2330 of the EU Habitat Directive. They are threatened by different factors (such as restricted areas of occurrence, alien plant invasion and natural dynamics) and they need to be managed if we want to conserve them.     

How far a protected area contributes to conserve habitat species composition and population structure of endangered African tree species (Benin,West Africa)

The Pendjari Biosphere Reserve located in the Sudanian zone of Bénin, is a protected area well managed, but mainly aimed at wild animal conservation. This study assessed its effectiveness to conserve habitat species composition and population structure of three endangered African tree species: Afzelia africana Sm., Pterocarpus erinaceus Poir. and Khaya senegalensis (Desv.) A. Juss. We randomly sampled 120 plots in the protected and surrounding unprotected habitats by inventorying plant species. For the three target species, we estimated adult and juvenile densities and recorded size classes. According to floristic composition four habitats groups were recognized in relation to human disturbance, vegetation type, and moisture. These were protected savannas, unprotected savannas, old fallows and gallery forests. The estimated adult densities of A. africana were similar between protected (14 ± 1.2 tree/ha) and unprotected savannas (17 ± 0.9 tree/ha) while for P. erinaceus the adult density was significantly higher in protected (12 ± 3.7 tree/ha) than in unprotected savannas (5 ± 1.9 tree/ha). Estimated adult density of K. senegalensis was also significantly higher in protected gallery forest (40 ± 5.8 tree/ha) than in unprotected one (29 ± 4.8 tree/ha). Juvenile densities of A. africana, K. senegalensis and P. erinaceus were higher in protected habitats than in unprotected ones but the difference was not significant. Skewness coefficient indicated that populations of investigated trees were declining in their protected habitats. However, in the case of A. africana and K. senegalensis populations seemed to be mostly threatened in the protected area. We concluded that although the studied protected area is effective to conserve some habitats species compositions, protection is not sufficient to guarantee future conservation of some threatened tree species.     

Avian fossil assemblages at the onset of the LGM in the eastern Alps: A palaecological contribution from the Rio Secco Cave (Italy)

The avian fossil assemblages from the late Pleistocene deposits of the Rio Secco Cave (north-eastern Italy) is presented herein. We studied the layers that date back to the end of MIS3 and the beginning of MIS2, which also contain evidence of Gravettian frequentation dated to 33.5–30 ka cal BP. The systematic analysis revealed the presence of 18 species and other supraspecific taxa that supported palaeoenvironmental reconstructions. Taxa indicate that, at the onset of LGM, site surroundings were characterised by conifer or mixed forests, open grasslands, slow-flowing water bodies and mountain meadows with rocky outcrops, as indicated by Lagopus muta. Today, this environment is found above the tree line (beyond 1500–2000 m) and cannot be detected near the site, located at 580 m asl. Noteworthy, is also the finding of the second Italian late Pleistocene fossil record of Picus canus.     

Vibrio aestivus sp. nov. and Vibrio quintilis sp. nov., related to Marisflavi and Gazogenes clades,respectively

Two new Vibrio species, Vibrio aestivus and Vibrio quintilis, are described after a polyphasic characterization of strains M22^T, M61 and M62^T, isolated from seawater collected off a beach on the East coast of Spain (Valencia). All three strains are Gram negative, mesophilic, slightly halophilic, fermentative rods. V. aestivus (M22^T = CECT 7558^T = CAIM 1861^T = KCTC 23860^T and M61 = CECT 7559 = CAIM 1862 = KCTC 23861) is oxidase positive, reduces nitrates to nitrites, is negative for Voges Proskauer, arginine dihydrolase and indole and non hydrolytic on most substrates tested. The 16S rRNA gene sequences of M22^T and M61 are most similar to Vibrio marisflavi (97.1–97.2%) but phylogenetic analysis using NJ, MP and ML methods display Vibrio stylophorae (96.2% similarity) as sibling species. The three species form a deep clade in the genus Vibrio. Average Nucleotide Identity (ANI) values, determined as a measure of overall genomic resemblance, confirmed that strains M22^T and M61 are members of the same species, different to V. marisflavi CECT 7928^T.V. quintilis (M62^T = CECT 7734^T = CAIM 1863^T = KCTC 23833^T) is aerogenic, arginine dihydrolase and Voges Proskauer positive, oxidase negative and unable to reduce nitrate, traits shared by most species in the Gazogenes clade. It is unpigmented and does not grow on TCBS Agar. 16S rRNA gene similarities to its nearest species, Vibrio aerogenes and Vibrio mangrovi, are 97.6% and 96.0% respectively. Strain M62^T and V. aerogenes CECT 7868^T display ANI values well below the 95% boundary for genomic species.     

Population structure and genetic diversity of Dysosma versipellis (Berberidaceae), a rare endemic from China

Dysosma versipellis (Berberidaceae) is an endangered and endemic species in China. To provide scientific foundation for formulating conservation strategies, we sampled six extant populations of this species and assessed the levels and patterns of genetic diversity using ISSR markers (11 primers). Of 144 bands detected 57.64% were polymorphic, but on average only 20.72% were polymorphic within populations. Our results revealed a low level of intraspecific genetic diversity (at population level: H_pop = 0.082, H_B = 0.177, SI = 0.1194; at species level: H_pop = 0.207, H_B = 0.378, SI = 0.3069). A high level of genetic differentiations among populations was detected based on Nei's genetic diversity analysis (60%), AMOVA analysis (65%), and Bayesian analysis (53%). The low levels of heterozygosity and high genetic differentiation observed in D. versipellis may be the consequence of low rate of natural recruitment, clonal growth, gene drift, and habitat fragmentation. Based on this, we suggest that in situ conservation be an important and practical measure for maintaining the genetic diversity of this species. Ex situ conservation should sample from different populations across the distribution range of the species to conserve high genetic diversity.     

Modelling geographic distribution and detecting conservation gaps in Italy for the threatened beetle Rosalia alpina

Presence-only models can aid conservation and management of threatened, elusive species. We developed a Maxent model for the rare cerambycid beetle Rosalia longicorn Rosalia alpina L. in Italy and neighbouring regions and identified the variables best explaining the species’ occurrence on a large scale. Once successfully validated, we used the model to (a) evaluate the current degree of fragmentation of R. alpina range in Italy; and (b) quantify the amount of the Italian territory with the highest probability of beetle presence within the existing national conservation areas (Natura 2000 network, parks and reserves). Low (<0.5) probability scores of R. alpina presence corresponded to 89% of the total area considered, whereas high scores (>0.9) covered only 2.5%. R. alpina was predicted to occur mostly in broadleaved deciduous forest at 1000–1700 m a.s.l. with warm maximum spring temperatures and May and November precipitation >80 mm. We found a high degree of fragmentation; gaps were mainly covered with farmland or other unsuitable habitat. Over 52% of potential habitat is unprotected. While the Natura 2000 network protects 42% of potential habitat, parks and reserve covers less than 29%. To preserve R. alpina, we urge to create, or restore, forest corridors to bridge the otherwise impermeable gaps our model detected and grant protection to the still largely unprotected area of the Italian territory e.g. by including it in further Natura 2000 sites. Models such as ours may also help focus field surveys in selected areas to save resources and increase survey success.     

Germination et croissance des plantules de hêtre (Fagus sylvatica) sous contraintes climatiques et allélopathiques

Recruitment is a key process for forest sustainability, especially in warm margin of distribution area. The influence of climate (temperate or warm), of soil water availability, and of allelopathic interactions from different forest species have been tested on the germination of Fagus sylvatica in controlled climatic conditions. Germination rates of non-dormant Fagus seeds were improved by relatively warm temperatures (20 °C), but reversibly stopped under heat constraint (27 °C). The relative growth rate of Fagus seedlings was better under temperate climatic conditions. Foliar extracts of Hedera helix showed the highest allelopathic effect on Fagus recruitment, especially in temperate conditions. Our results suggest a limitation of Fagus recruitment in warm margin of its distribution area, and a modulation of recruitment success according to the identity of plant neighbourhood.     

The influence of abiotic stress and phenotypic plasticity on the distribution of invasive Alternanthera philoxeroides along a riparian zone

Relatively few studies have compared invasibility and species invasiveness among microhabitats within communities, synchronously. We surveyed the abundance and performance of non-native Alternanthera philoxeroides (Mart.) Griseb. (alligator weed), its co-occurring native congener, Alternanthera sessilis (L.) DC. (sessile joyweed), and other species in a wetland community along a riparian zone in southeast China to test the hypotheses that: i) degree of invasion differs between different types of microhabitats within the community; and ii) microhabitat types that differ in invasibility also differ in soil resource availability or in sediment characteristics likely to affect resource availability; iii) phenotypic plasticity of A. philoxeroides may play a key role in its adaptation to diverse habitats as can be concluded from its extremely low genetic diversity in China. The study riparian zone comprises different types of microhabitats including wet abandoned field, swamp, marsh dunes and gravel dunes. Consistent with these hypotheses, cover of A. philoxeroides was high in abandoned fields (73 ± 2.9%) and swamps (94 ± 1.3%), which had high soil nutrients and water availability. On the contrary, cover of native A. sessilis was relatively high in marsh dunes and grave dunes, which had coarse gravel surfaces, low soil nutrients and low water availability. A. philoxeroides showed greater morphological plasticity in response to habitat variation. In abiotically harsh habitats, stems had limited growth, and were prostrate with weak adventitious roots at nodes, forming thin, scattered patches. In the two richer habitats, the highly branched plants spread over the water or soil surface, supporting dense stronger leaf-bearing stems which grew vertically. The growth pattern of A. sessilis among microhabitats did not exhibit significant variations. These results suggest that morphological plasticity and microhabitat types with high soil resources may facilitate invasions of A. philoxeroides.     

Pharmacological properties and in vitro shoot production of Barleria argillicola – A critically endangered South African species

Barleria argillicola Oberm. is a critically endangered species, endemic to a small area in the KwaZulu-Natal Province, South Africa. Animals are known to forage on this plant species, suggesting its therapeutic or nutraceutical potential. This study investigated the antibacterial, acetylcholinesterase inhibition, antioxidant and phytochemical properties of this species with a view to exploring its medicinal potential. The possibility of in vitro propagation as a conservation strategy was also examined. Dichloromethane extract showed a good antibacterial activity (with minimum inhibitory concentration less than 1 mg/ml) against all the tested micro-organisms. Methanol extract exhibited a stronger antibacterial activity against the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa than the Gram-positive bacterium Staphylococcus aureus. Extracts obtained from the aerial parts and roots demonstrated a dose-dependent acetylcholinesterase inhibition and antioxidant activities. Higher iridoid, flavonoid and condensed tannin contents were recorded in the aerial parts compared to the roots although the total phenolic content was higher in the roots. The highest in vitro shoot proliferation of 4.60 ± 0.51 and 4.0 ± 0.47 shoots per explant was achieved using shoot-tip and single nodal explants respectively, after four weeks of culture in Murashige and Skoog medium supplemented with 5 μM benzyladenine riboside (BAR). Further supplementation of the medium with naphthalene acetic acid (NAA) or indole butyric acid (IBA) concentrations did not significantly increase shoot proliferation.     

Support vector machines to model presence/absence of Alburnus alburnus alborella (Teleostea,Cyprinidae) in North-Western Italy: Comparison with other machine learning techniques

Alburnus alburnus alborella is a fish species native to northern Italy. It has suffered a very sharp decrease in population over the last 20 years due to human impact. Therefore, it was selected for reintroduction projects. In this research project, support vector machines (SVM) were tested as possible tools for building reliable models of presence/absence of the species. A system of 198 sites located along the rivers of Piedmont in North-Western Italy was investigated. At each site, 19 physical-chemical and environmental variables were measured. We verified that performances did not improve after feature selection but, instead, they slightly decreased (from Correctly Classified Instances [CCI] = 84.34 and Cohen's k [k] = 0.69 to CCI = 82.81 and k = 0.66). However, feature selection is crucial in identifying the relevant features for the presence/absence of the species. We then compared SVMs performances with decision trees (DTs) and artificial neural networks (ANNs) built using the same dataset. SVMs outperformed DTs (CCI = 81.39 and k = 0.63) but not ANNs (CCI = 83.03 and k = 0.66), showing that SVMs and ANNs are the best performing models, proving that their application in freshwater management is more promising than traditional and other machine-learning techniques.     

Selection by climatic regime and neutral evolutionary processes in holocentric chromosomes (Carex gr. laevigata: Cyperaceae): A microevolutionary approach

The holocentric structure promotes chromosome rearrangements by fission, fusion, translocation, and inversion, which have been thought to promote differentiation and speciation. The Carex laevigata group (Cyperaceae) comprises four species: two restricted endemics from the western Mediterranean (Carex camposii, 2n = 72, and Carex paulo-vargasii, 2n = 74–75), and two more widespread species, found mostly in Western Europe (C. laevigata, 2n = 69–84, and Carex binervis, 2n = 72–74). We tested the selection for chromosome number by climatic variables by controlling for the non-independence of the data using generalized linear mixed model (GLMM). We obtained chromosome counts as well as DNA sequences for the 5′ trnK intron and the trnV-ndhC intergenic spacer in the chloroplast genome from 181 individuals from 53 populations representing these four species. We also climatically characterized the sites where the 53 populations were found using the WorldClim database. Our results show that the best predictor of chromosome number variation is the climatic environment rather than neutral evolutionary processes like founder events and migration patterns. These results support the adaptive value of the holocentric chromosomes and their role in promoting differentiation and eventually speciation.