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The performance of seedlings is crucial for the survival and persistence of plant populations. Although drought frequently occurs in floodplains and can cause seedling mortality, studies on the effects of drought on seedlings of floodplain grasslands are scarce. We tested the hypotheses that drought reduces aboveground biomass, total biomass, plant height, number of leaves, leaf area and specific leaf area (SLA), and increases root biomass and root-mass fraction (RMF) and that seedlings from species of wet floodplain grasslands are more affected by drought than species of dry grasslands. In a greenhouse study, we exposed seedlings of three confamilial pairs of species (Pimpinella saxifraga, Selinum carvifolia, Veronica teucrium, Veronica maritima, Sanguisorba minor, Sanguisorba officinalis) to increasing drought treatments. Within each plant family, one species is characteristic of wet and one of dry floodplain grasslands, confamilial in order to avoid phylogenetic bias of the results. In accordance with our hypotheses, drought conditions reduced aboveground biomass, total biomass, plant height, number of leaves and leaf area. Contrary to our hypotheses, drought conditions increased SLA and decreased root biomass and RMF of seedlings. Beyond the effects of the families, the results were species-specific (V. maritima being the most sensitive species) and habitat-specific. Species indicative of wet floodplain grasslands appear to be more sensitive to drought than species indicative of dry grasslands. Because of species- and habitat-specific responses to reduced water availability, future drought periods due to climate change may severely affect some species from dry and wet habitats, while others may be unaffected.

In stressful and harsh environments, safe sites for seedling recruitment may be created by nurse plants, which accumulate propagules and subsequently facilitate the establishment of individuals. The main goal of the presented studies focused on observations of seedling recruitment in small and large tussocks of Deschampsia caespitosa derived from patches of unmanaged Molinietum caeruleae meadows situated along the successional gradient and dominated by small meadow species (Patch I), by macroforbs (Patch II), or overgrown by trees and shrubs (Patch III). The studies showed that, irrespective of patch character, Serratula tinctoria, Selinum carvifolia, Lysimachia vulgaris and Filipendula ulmaria are among the best colonizers of Deschampsia caespitosa tussocks. The gradual decrease in number of species and offspring abundance along the successional gradient may be connected with a prolonged period of water stagnation accelerating the development of fungal pathogens, a major cause of mortality for ...

The dynamics of many plant populations essentially depend upon seed and seedling stages, and a persistent seed bank may give species an opportunity to disperse through time. Seed burial is a decisive prelude to persistence and may strongly influence seed-bank dynamics. The fate of buried seeds depends on species-specific traits, environmental conditions and possibly also burial mode. We tested seed germination, seedling emergence and growth of the co-occurring herbaceous flood-meadow speciesArabis nemorensis,Galium wirtgenii,Inula salicina,Sanguisorba officinalisandSelinum carvifoliain response to the experimental manipulation of burial depth (0, 1, 2, 4, 8, 12 cm) and substrate type (sand, clay). Increasing burial depth led to decreased germination, emergence and growth in all species studied, and seedling growth differed significantly between substrate types. The responses of species differed on an individual basis, but also showed a higher-ranking pattern based on seed size. Larger-seeded species were able to emerge from greater depths and experienced less depth-mediated growth inhibition than smaller-seeded species, which, in turn, had higher survival rates during burial and were less likely to experience fatal germination. Based on these results, we suggest that herbaceous flood-meadow species have developed two different seed-size based strategies for coping with the extreme recruitment conditions prevailing in flood meadows, the balance of which seems to be maintained by disturbance events.

International audience; Evaluating the consequences of the decline of threatened species on their population genetic structure is crucial for establishing effective conservation strategies in the strongly fragmented landscapes of Central Europe. Laserpitium prutenicum is a bi- to perennial forb occurring in intermittently wet meadows and light oak forests throughout central to eastern and south-eastern Europe. During the past 70 years, the western limit of its distributional range retracted dramatically, the number of populations decreased and the remaining populations faced a considerable increase of fragmentation. To study the effects of this decline on the genetic diversity of L. prutenicum, we conducted an AFLP study on 20 populations from Germany, Poland and the Czech Republic. For comparison, we collected the same data on Selinum carvifolia, a taxonomically related and both ecologically and morphologically similar species, which is still more common in the study area. Both species showed similarly weak spatial genetic structuring and intermediate genetic diversities. We attribute this result to the loss of habitat being faster than the loss of genetic diversity in smaller and fragmented populations. Depending on the ecological characteristics of a species, even a gradual disappearance is not necessarily accompanied by any detectable effect at the population genetic level ("silent goodbye"). In the case of L. prutenicum, habitat preservation should be given priority over all other conservation measures.

Germination and dormancy breaking requirements were studied in Selinum carvifolia (L.) L. and Angelica sylvestris L. (Apiaceae). Seeds of these two species have an underdeveloped embryo and are morpho-physiologically dormant. The embryo does not start to grow until physiological dormancy is broken by cold stratification. Incubating seeds at fluctuating temperatures in the light, after cold stratification, had a stimulating effect on embryo growth and seed germination. Seeds of S. carvifolia and A. sylvestris have non-deep simple morphophysiological dormancy (MPD), since gibberellic acid (GA3) could substitute for cold stratification. This is the first report of non-deep simple MPD that is broken by cold stratification in the Apiaceae. Under natural conditions, physiological dormancy is broken by low temperature conditions during winter. Embryo growth and germination occur in a short time interval when temperatures start rising in early spring. Due to the fact that multiple environmental signals regulate dormancy, seedling emergence in these species is timed very accurately in spring.

Changes in the relative availability of essential nutrients such as nitrogen, phosphorus, and potassium can be associated with changes in the species composition of wetland vegetation, but responsible mechanisms are not always clear. This study examines how the relative supply of N and P influences the composition of mixtures of four herbaceous wetland species (Carex flava, Centaurea angustifolia, Lycopus europaeus and Selinum carvifolia). Mixtures were grown in sand fertilised with nutrient solutions containing N and P in varying proportions (N:P mass ratios of 1.7–135) and total amounts (‘overall supply’, geometric mean of N and P supply). The total above-ground biomass of the mixtures after 11 weeks of growth depended mainly on overall nutrient supply, but also on the N:P supply ratio; it was maximal at a N:P supply ratio of 15 with high overall nutrient supply, 45 with intermediate, and 135 with low nutrient supply. The relative contributions of the four species to total above-ground biomass as well as the root weight ratio differed significantly among nutrient treatments. Treatment effects mostly remained significant when biomass was used as covariate to account for differences in productivity. With increasing N:P supply ratio, the contribution of C. flava increased, while the contribution of L. europaeus and the root weight ratio tended to decrease. These differences were unrelated to interspecific differences in biomass N and P concentrations since L. europaeus had lower concentrations of both N and P than C. flava. Differences in the rates of N and P uptake were apparently most important in this short-term experiment and probably due to differences in biomass allocation to roots. The results also show that the effects of N:P supply ratios should always be investigated at several levels of overall nutrient supply since the two factors interact with each other. Veranderungen der relativen Verfugbarkeit wichtiger Nahrstoffe wie Stickstoff, Phosphor und Kalium in Feuchtgebieten konnen mit Veranderungen der Artenzusammensetzung der Vegetation verbunden sein, doch die verantwortlichen Mechanismen sind nicht immer offensichtlich. Hier wurde untersucht, wie das Verhaltnis von N- zu P-Versorgung die Zusammensetzung (Biomasseanteile) von Mischungen aus vier Feuchtgebietsarten (Carex flava, Centaurea angustifolia, Lycopus europaeus und Selinum carvifolia) beeinflusst. Die Mischungen wurden in Quarzsand kultiviert und mit N und P in unterschiedlichen Verhaltnissen (Massenverhaltnisse von 1.7–135) und Gesamtmengen (geometrisches Mittel von N- und P-Menge) versorgt. Die gesamte oberirdische Biomasse nach elf-wochigem Wachstum hing hauptsachlich von der Gesamtversorgung ab, aber auch vom N:P-Verhaltnis; sie war am hochsten wenn das N:P-Verhaltnis bei hoher Gesamtversorgung 15 war, bei mittlerer Gesamtversorgung 45 und bei niedriger Gesamtversorgung 135. Die Biomasseanteile der vier Arten sowie der Wurzelanteil hingen von den Behandlungen ab. Die Behandlungseffekte blieben zum grosten Teil signifikant wenn die Biomasse als Kovariable verwendet wurde, um den Einfluss von Produktivitatsunterschieden auszuschliesen. Mit zunehmendem N:P-Verhaltnis nahm der Biomasseanteil von C. flava zu, wahrend der Anteil von L. europaeus und der Wurzelanteil abnahmen. Diese Verschiebungen hingen nicht mit unterschiedlichen Nahrstoffkonzentrationen in der Biomasse zusammen, da sowohl die N- als auch die P-Konzentration bei L. europaeus niedriger war als bei C. flava. Demnach waren Unterschiede bei der N- und P-Aufnahme entscheidend, und diese lagen vermutlich an unterschiedlichen Wurzelanteilen. Die Ergebnisse zeigen auch, dass der Einfluss der relativen Verfugbarkeit von N und P stets bei mehreren Gesamtgaben untersucht werden sollte, da die Wirkung der zwei Faktoren voneinander abhangt.

This preliminary study examined the arbuscular mycorrhizal (AM) status of native plant species in the Molinia meadows of Folusz in the Kujawy region, Poland. Root samples from ten plant species characteristic of Molinia meadows ( Betonica officinalis , Dianthus superbus , Galium boreale , Inula salicina , Ostericum palustre , Sanguisorba officinalis , Selinum carvifolia , Serratula tinctoria , Silaum silaus , and Succisa pratensis ) were collected in August 2014. Root colonization by AM fungi was considered an indicator of symbiosis development. AM was found in all plant species examined. The frequency of mycorrhizal structures ranged between 68% and 99%. The intensity of mycorrhizal colonization in roots varied with the plant species, ranging between 3.9% ( O. palustre ) and 40.1% ( B. officinalis ). To our knowledge, this is the first study to examine the mycorrhizal status of three species: D. superbus , O. palustre , S. carvifolia . Because AM colonization depends on plant genotype and environmental factors, further studies should examine seasonal variability in plant root colonization and the compositions of AM fungal communities, which may serve as indicators of site conditions

The paper presents characteristics of a meadow community with Trollius europaeus , threats posed to the community, and proposals for active protection thereof. The study was carried out in the “Łąki w Komborni” Natura 2000 site (PLH 180042) in the Podkarpacie Province (SE Poland). In 2015, 20 releves were taken with the Braun-Blanquet method and they are presented in a synthetic table. Additionally, the number of clumps, the number of flowering shoots per clump, and the height of flowering shoots were determined. The community with Trollius europaeus was classified into the alliance Molinion caeruleae with Selinum carvifolia , Galium boreale , Succisa pratensis , Betonica officinalis , Gladiolus imbricatus , and Carex tomentosa as characteristic species. Scrub species, in particular Filipendula ulmaria , had a substantial share, which indicated long-term abandonment of land use. The community also comprised rush species ( Carex gracilis , Phragmites australis ) and a numerous group of species from the order Arrhenatheretalia (e.g. Geranium pratense , Alchemilla monticola , Galium mollugo , Arrhenatherum elatius ) and the class Molinio-Arrhenatheretea (e.g. Lathyrus pratensis , Alopecurus pratensis , Ranunculus acris , Poa pratensis ). Abandonment of extensive land use leading to progressive secondary succession is the major threat to phytocoenoses with Trollius europaeus . To preserve meadows with Trollius europaeus , active protection involving mowing and removal of biomass is recommended.

Selinum carvifolia (Linnaeus) Linnaeus, Species Plantarum, ed. 2, 1: 350. 1762, typ. cons. "Habitat in Sibiriae campis a Jacco ad Obium, in Germania." RCN: 1960. Basionym: Seseli carvifolia L. (1753). Lectotype (Reduron & Jarvis in Jarvis & al., Regnum Veg. 127: 87. 1993): [icon] " Angelica tenuifolia " in Rivinus, Ordo Pl. Fl. Pentapetal.: t. 18. 1699. Generitype of Selinum Linnaeus (1762), nom. cons. Current name: Selinum carvifolia (L.) L. (Apiaceae). Note: Selinum Linnaeus (1762), nom. cons. against Selinum Linnaeus (1753), nom. rej., Published as part of Jarvis, Charlie, 2007, Chapter 7: Linnaean Plant Names and their Types (part S), pp. 806-877 in Order out of Chaos. Linnaean Plant Types and their Types, London :Linnaean Society of London in association with the Natural History Museum on page 838, DOI: 10.5281/zenodo.291971