The effects of lead (Pb) stress on plant growth and physiological processes may depend on other environmental stresses coinciding. Knowledge of the response of shade-loving plants to stresses, particularly the relationship between Pb stress and light stress, is lacking. The effects of single and combined Pb and light stress on the growth and physiological parameters of Polystichum setiferum and Polystichum setiferum ‘Proliferum’ ferns were evaluated under glasshouse conditions. Treatments comprised control (80% shade, ~111 μmol m−2 s−1 photosynthetic photon flux density, PPFD), light stress (100% full sunlight, ~525 μmol m−2 s−1 PPFD), 1000 mg dm−3 Pb solution applied to plants under shade and light stress conditions. Under full sunlight, plants had damaged leaves and reduced leaf biomass, and underground parts of the plants had levels of photosynthetic pigments, reducing sugars and total flavonoids. The Pb stress decreased plant growth, reducing sugars, and free amino acids content, and at the same time increased chlorophyll content in P. setiferum and total polyphenols and flavonoid content in P. setiferum ‘Proliferum’. The combined stress of Pb and full sunlight reduced plant growth and the accumulation of pigments, reducing sugars, and free amino acids without affecting the levels of secondary metabolites. P. setiferum plants accumulated more Pb than P. setiferum ‘Proliferum.’ The fern P. setiferum ‘Proliferum’ was more tolerant to abiotic stresses than the fern P. setiferum. This study provided new insights into the response of shade-loving ornamental plants to single and combined Pb and light stress.

Abstract During field studies in 2019 in the Beskid Śląski mountain range in southern Poland, one individual morphologically resembling Polystichum setiferum was found. Nuclear DNA content analysis confirmed the species identity. The new stand of P. setiferum corresponds to historical literature reports and herbarium specimens from the Czech Republic and Poland, and extends the northeastern limit of the distribution of this species. As the historical stands in both countries have not been confirmed, the newly discovered stand is at present strongly isolated, as the nearest extant locations of P. setiferum in Austria, southern Hungary, and western Romania are nearly 500 km away. Therefore, this unique stand deserves special attention and protection.

This paper summarizes the phytosociological characteristics of scree forests (Tilio tomentosae-Fraxinetum orni) found in the Villány Hills, SW Hungary.The studied stands grow within the belt of oakhornbeam forests on northerly slopes covered with stony soil.They are under relatively strong sub-Mediterraneam climatic influence as attested by the occurrence of several Aremonio-Fagion and Quercion farnetto species : Asperula taurina, Doronicum orientale, Helleborus odorus, Lathyrus venetus, Lonicera caprifolium, Lunaria annua, Polystichum setiferum, Primula vulgaris, Rosa arvensis, Ruscus aculeatus, Ruscus hypoglossum, Scutellaria altissima, Tamus communis and Tilia tomentosa.The distribution of character species proportions is similar to that in the scree forests in the Mecsek Hills, with the exception of Quercetea pubescentispetraeae s.l. as well as Fagetalia and Tilio-Acerenion species that play a more and a less significant role, respectively.Syntaxonomically, this community is best assigned to the "Polysticho setiferi-Acerenion pseudoplatani Borhidi & Kevey 1996" suballiance.

Leaf mass per area (LMA) is one of the key features that correlates with the ecological performance both of seed plants and ferns. For ferns LMA is at the lower end of the range for seed plants and increases with leaf longevity. Data concerning morphological and anatomical traits of ferns and their relationship with LMA are quite limited. The objectives of this study were to (1) break down LMA into anatomical components; and (2) analyze the trade-offs between anatomical and morphological leaf traits, which determine LMA variations for three evergreen ferns. Seven morphological and 16 anatomical leaf traits of Polystichum setiferum, Polypodium interjectum and Asplenium scolopendrium growing outdoors in the Botanical Garden of Rome were analyzed using light microscopy. LMA was not significantly different between the considered species (4.55±0.55, 4.34±0.47, 4.28±0.41 mg cm−2 respectively) and it was in the range of other evergreen fern species. The morphological and anatomical structure of all species was significantly different and reflected environmental adaptation of species to their natural habitats. In particular, total lamina thickness was163±16.1 μm (P. setiferum), 244±33.7 μm (P. interjectum) and 336±32.2 μm (A. scolopendrium); leaf tissues density ranged from 127±16.9 mg cm−3 (A. scolopendrium) to 277±37.1 mg cm−3 (P. setiferum); intercellular air space varied between 23.2±2.07% (P. interjectum) and 41.8±1.61% (A. scolopendrium). The overall results highlight that LMA is an integral feature that can be obtained by different anatomical structure.

The endocrine disruptor nonylphenol induces sublethal toxicity in vascular plant development at environmental concentrations: A risk for riparian plants and irrigated crops?

Development of cost-effective strategies for environmental monitoring of irrigated areas in Mediterranean regions: Traditional and new approaches in a changing world

New microbioassays based on biomarkers are more sensitive to fluvial water micropollution than standard testing methods

I present the results of a phytosociological analy-sis of 50 samples of oak-hornbeam forests on sand (Fraxino pannonicae-Carpinetum), which grow in the southwestern part of Hungary in Inner Somogy. The habitat of these forests is un-der slight influence of groundwater, which manifests itself in the species composition of these forests. The forests differ sharply from the oak-hornbeam forests (Helleboro dumetorum-Carpin-etum) growing on loess in the neighbouring Zselic. The species composition somewhat resembles that of hardwood gallery for-ests on sand (Knautio drymeiae-Ulmetum), beech woods on sand (Leucojo verno-Fagetum), and oak-hornbeam forests along the Dráva River (Veronico montanae-Carpinetum). The Fagetalia elements in its understorey (Actaea spicata, Astran-tia major, Dentaria enneaphyllos, Oxalis acetosella, etc.) are probably relics of the Beech I. phase (2500 and 800 B.C.) of the Holocene, when the climate was more humid and less ex-treme. It also hosts species typical of the Aremonio-Fagion alli-ance (pl. Carex strigosa, Cyclamen purpurascens, Doronicum orientale, Erythronium dens-canis, Knautia drymeia, Polysti-chum setiferum, Primula vulgaris, Ruscus aculeatus, Tamus communis, Tilia tomentosa), whereby it exhibits a moderate sub-Mediterranean character.

Preliminary data suggest that venlafaxine environmental concentrations could be toxic to plants

Populations established by long-distance colonization are expected to show low levels of genetic variation per population, but strong genetic differentiation among populations. Whether isolated populations indeed show this genetic signature of isolation depends on the amount and diversity of diaspores arriving by long-distance dispersal, and time since colonization. For ferns, however, reliable estimates of long-distance dispersal rates remain largely unknown, and previous studies on fern population genetics often sampled older or non-isolated populations. Young populations in recent, disjunct habitats form a useful study system to improve our understanding of the genetic impact of long-distance dispersal. Microsatellite markers were used to analyse the amount and distribution of genetic diversity in young populations of four widespread calcicole ferns (Asplenium scolopendrium, diploid; Asplenium trichomanes subsp. quadrivalens, tetraploid; Polystichum setiferum, diploid; and Polystichum aculeatum, tetraploid), which are rare in The Netherlands but established multiple populations in a forest (the Kuinderbos) on recently reclaimed Dutch polder land following long-distance dispersal. Reference samples from populations throughout Europe were used to assess how much of the existing variation was already present in the Kuinderbos. A large part of the Dutch and European genetic diversity in all four species was already found in the Kuinderbos. This diversity was strongly partitioned among populations. Most populations showed low genetic variation and high inbreeding coefficients, and were assigned to single, unique gene pools in cluster analyses. Evidence for interpopulational gene flow was low, except for the most abundant species. The results show that all four species, diploids as well as polyploids, were capable of frequent long-distance colonization via single-spore establishment. This indicates that even isolated habitats receive dense and diverse spore rains, including genotypes capable of self-fertilization. Limited gene flow may conserve the genetic signature of multiple long-distance colonization events for several decades.

Comparative evaluation of acute toxicity by Vibrio fischeri and fern spore based bioassays in the follow-up of toxic chemicals degradation by photocatalysis

BackgroundPrevious studies on the reproductive biology of ferns showed that mating strategies vary among species, and that polyploid species often show higher capacity for self-fertilization than diploid species. However, the amount of intraspecific variation in mating strategy and selfing capacity has only been assessed for a few species. Yet, such variation may have important consequences during colonization, as the establishment of any selfing genotypes may be favoured after long-distance dispersal (an idea known as Baker's law).ResultsWe examined intra-and interspecific variation in potential for self-fertilization among four rare fern species, of which two were diploids and two were tetraploids: Asplenium scolopendrium (2n), Asplenium trichomanes subsp. quadrivalens (4n), Polystichum setiferum (2n) and Polystichum aculeatum (4n). Sporophyte production was tested at different levels of inbreeding, by culturing gametophytes in isolation, as well as in paired cultures with a genetically different gametophyte. We tested gametophytes derived from various genetically different sporophytes from populations in a recently planted forest colonized through long-distance dispersal (Kuinderbos, the Netherlands), as well as from older, less disjunct populations.Sporophyte production in isolation was high for Kuinderbos genotypes of all four species. Selfing capacity did not differ significantly between diploids and polyploids, nor between species in general. Rather selfing capacity differed between genotypes within species. Intraspecific variation in mating system was found in all four species. In two species one genotype from the Kuinderbos showed enhanced sporophyte production in paired cultures. For the other species, including a renowned out crosser, selfing capacity was consistently high.ConclusionsOur results for four different species suggest that intraspecific variation in mating system may be common, at least among temperate calcicole ferns, and that genotypes with high selfing capacity may be present among polyploid as well as diploid ferns. The surprisingly high selfing capacity of all genotypes obtained from the Kuinderbos populations might be due to the isolated position of these populations. These populations may have established through single-spore colonization, which is only possible for genotypes capable of self-fertilization. Our results therewith support the idea that selection for selfing genotypes may occur during long-distance colonization, even in normally outcrossing, diploid ferns.

Studies on the biogeography and population genetics of the widespread European rock ferns Asplenium scolopendrium, A. trichomanessubsp. quadrivalens, Polystichum setiferum, and P. aculeatumwould potentially yield interesting new insights into the colonization capacities of ferns. Markers with sufficient resolution for detailed genetic studies are, however, not yet available. Using genome screening with intersimple sequence repeat (ISSR) primers, a total of 16 different microsatellite markers were isolated and characterized for the four species. Some of these markers could be exchanged within each congeneric pair. The developed primer sets will be very useful for analyses of the biogeography and population genetics of some widespread calcicole ferns. The observed cross-amplification rates suggest a high potential for application on additional species from the same genera.

Six French ferns were investigated for volatile organic compounds (VOC) by GC-MS using organic solvent extraction. Seventy-seven VOC biosynthesized from the shikimic, lipidic and terpenic pathways, including isoprenoid derivatives, were identified from these putative natural resources. Asplenium trichomanes subsp. trichomanes contained mainly polyketides with an oily or waxy odor. (E)-2-Hexenal and (Z)-3-hexenol, responsible for the "green odor", were found in high contents in Polystichum setiferum, Dryopteris dilatata and Phegopteris connectilis. In the last, 7.4% of coumarin with a cut hay scent was highlighted from the volatile fraction. (E)-3-Hexenoic acid and (E)-2-hexenoic acid, both with herbal and fruity notes, were identified in Gymnocarpium dryopteris and Pteridium aquilinum. 1-Octen-3-ol, well-known for its mushroom-like odor, was abundant in all analyzed French ferns. While the "fougère" fragrance is claimed by the perfumers to be a fantasy scent, coumarin, (E)-2-hexenal, (Z)-3-hexenol and 1-octen-3-ol are the main odorous components of the perfumes belonging to the fougère accord family. This suggests that the fougère scent from the perfumers' imagination is a natural fragrance.

The development of suitable biomarker-based microbioassays with model species with ecological relevance would help increase the cost-efficiency of routine environmental monitoring and chemical toxicity testing. The anti-inflammatory drug diclofenac has been widely reported in the environment but ecotoxicological data are scarce. The aim of this work is to assess the acute and chronic sublethal toxicity of diclofenac in relevant taxa of aquatic and riparian ecosystems (the fish Danio rerio and the fern Polystichum setiferum). Reliable biomarkers of cell viability (mitochondrial activity), plant physiology (chlorophyll), growth (DNA content) or oxidative damage (lipid peroxidation) were assessed as sensitive endpoints of toxicity. DNA quantification shows that diclofenac induces acute lethal phytotoxicity at 24 and 48h (LOECs 30 and 0.3μgl(-1), respectively). Hormetic effects in mitochondrial activity in spores of Polystichum setiferum mask lethality, and adverse effects are only observed at 48h (LOEC 0.3μgl(-1)). In chronic exposure (1week) LOEC for DNA is 0.03μgl(-1). Mitochondrial activity shows a strong hormetic stimulation of the surviving spore population (LOEC 0.3μgl(-1)). Little changes are observed in chlorophyll autofluorescence (LOEC 0.3μgl(-1)). A very short exposure (90min) of zebrafish embryos induces a reduction of lipid peroxidation at 0.03μgl(-1). Environmental concentrations of diclofenac can be deleterious for the development of significant populations of sensitive individuals in aquatic and riparian ecosystems.

Does forest fragmentation affect the same way all growth-forms?

We investigated the mechanism of antheridial dehiscence in ferns for the first time using fluorescence microscopy as well as scanning and transmission electron microscopy. The mechanism leading to antheridial dehiscence in Polystichum setiferum, Asplenium trichomanes and A. onopteris was found to depend on the different cellulose contents of the inner and outer walls of the ring cells detected with calcofluor white stain and the Thiery test. The extremely low cellulose content of the ring cell walls facing spermatozoids made them less mechanically resilient than external wall cells. When the ring cells absorbed water they expanded only into the antheridial cavity, pushing the gametes against the cap cell, which detached from the ring cell below and enabled spermatozoid release. The newly released spermatozoids were spherical bodies covered in cellulose fibrils. The significance of cellulose fibrils could be to isolate the gametes from each other, to reinforce the electron transparent material and to protect the gamete from pressure created by the ring cells during release.

Les bois d’aulne sont les forêts riveraines les plus diffusées au long des principaux fleuves de l’Italie péninsulaire. Dans beaucoup de sites de l’Italie centrale et méridionale on peut observer, même au long des cours d’eau mineurs, d’intéressants fragments de forêts qui ne sont pas encore entièrement compromis par l’action humaine. Cette étude relève l’importance du secteur Tyrrhénien de l’Italie centrale, au niveau floristique aussi qu’à celui végétationnel, et met en relief le rôle phytogéographique des vallons en tant qu’habitats utiles à la conservation des entités rares. Ce travail décrit les caractères physiognomiques, coenologiques et syntaxonomiques des fragments de forêts qui se trouvent au long de nombreux fleuves du Latium volcanique du nord (Tolfa). Ici, comme dans tout le territoire de la Maremma toscane et du Latium, on a plusieurs peuplements d’entités rares à l’échelle régionale et nationale (Osmunda regalis, Blechnum spicant, Polystichum setiferum, Dryopteris filix-mas et Athyrium filix-foemina) qui confirment l’existence de coenoses riveraines en état de bonne conservation. La présence de nombreuses entités intéressantes nous permet d’assigner les coenoses étudiées à l’association Polysticho-Alnetum glutinosae (alliance Osmundo-Alnion), un syntaxon riche en fougères hygrophiles qui montre la forte ressemblance avec les autres bois d’aulne avec fougères relevés en plusieurs sites de la Méditerranéen occidentale.

In this paper, the turkey oak forest fragments occurring in the Zákány Hills of SW Hungary are described and characterized based on 10 phytosociological samples. The stands grow on pebbly hilltops covered with loess. Their species composition features subcontinental-submediterranean and Illyrian influences: Anemone trifolia, Castanea sativa, Peucedanum verticillare, Polystichum setiferum, Primula vulgaris, Tamus communis. These forests are identified with the association Asphodelo-Quercetum roboris occurring in the sand hills and pebble hills in Transdanubia. Although to some degree these fragments represent transitional stands to the surrounding oak-hornbeam forests (Anemoni trifoliae-Carpinetum), they clearly differ in species composition. The association is classified into the suballiance Quercenion farnetto Kevey in Kevey et Borhidi 2005 within the alliance Quercion farnetto I. Horvat 1954.

Leaf hydraulic architecture and water relations of three fern species were measured. The species selected were adapted either to deeply shaded (Woodwardia radicans), moderately shaded (Dryopteris affinis) or moderately sunny (Polystichum setiferum) habitats, as confirmed by microclimatic measurements performed in the field. Leaf water potential (Ψleaf) was lower and leaf conductance to water vapour (gL) was higher in P. setiferum than in the shade-adapted ferns. Leaf osmotic potential and water potential at the turgor loss point were lower in the sun-adapted species than in the other ferns. Leaf hydraulic resistance (Rleaf) was lowest in P. setiferum and Rleaf was correlated with gL across species. Low Rleaf was coordinated with low rachis hydraulic resistance (Rrachis). Low values of Rrachis in P. setiferum were not due to the presence of wide xylem conduits as checked on the basis of anatomical measurements, but to increased radial permeability of vascular bundles. This was a consequence of the absence of endodermis surrounding the vascular bundles in P. setiferum, which was observed in the rachis of shade-adapted species. We conclude that hydraulic adjustment of fern fronds is a key component of adaptation of pteridophytes to contrasting light habitats.