Blechnum Spicant Research Articles

Comparative analysis of mycorrhizal communities associated with Struthiopteris spicant (L.) Weiss across Europe and North America.

Ferns constitute the second largest group of vascular plants. Previous studies have shown that the diversity and composition of fern communities are influenced by resource availability and water stress, among other factors. However, little is known about the influence of these environmental factors on their biotic interactions, especially regarding the relationship between mycorrhizal fungi and ferns. The present study compares the mycorrhizal communities associated with 36 populations of Struthiopteris spicant L. Weiss across Europe and North America. This species exhibits a great tolerance to variations in light, nutrient, and pH conditions, and it can survive with and without mycorrhizae. With the aim of determining which environmental factors impact the composition and abundance of the root-associated fungal communities in this species, we used an ITS-focused metabarcoding approach to identify the mycorrhizal fungi present and analyzed the influence of climatic and edaphic variables at global and regional scales. We encountered striking differences in the relative abundance of arbuscular mycorrhizal fungi (AMF) between S. spicant populations at both spatial levels. We recorded a total of 902 fungal ASVs, but only 2- 4% of the total fungal diversity was observed in each individual, revealing that each fern had a unique fungal community. Light availability and the interactive action of pH and soil nitrogen concentration showed a positive influence on AMF relative abundance, explaining 89% of the variance. However, environmental factors could only explain 4- 8% of the variability in AMF community composition, indicating that it might be determined by stochastic processes. These results support the hypothesis that ferns may be more independent of mycorrhization than other plant groups and interact with fungi in a more opportunistic manner.

Facultative mycorrhization in a fern (Struthiopteris spicant L. Weiss) is bound to light intensity

BackgroundThe establishment of mycorrhizal relationships between a fungus and a plant typically enhances nutrient and water uptake for the latter while securing a carbon source for the fungus. However, under a particular set of environmental conditions, such as low availability of light and abundant nutrients in the soil, the resources invested in the maintenance of the fungi surpass the benefits obtained by the host. In those cases, facultative mycorrhizal plants are capable of surviving without symbiosis. Facultative mycorrhization in ferns has been overlooked until now. The present study measured the response of Struthiopteris spicant L. Weiss, and its root-associated fungi to different levels of light and nutrient availability in terms of growth, mycorrhizal presence, and leaf nutrient content. This fern species exhibits a great tolerance to variable light, nutrient, and pH conditions, and it has been found with and without mycorrhizae. We conducted a greenhouse experiment with 80 specimens of S. spicant and three factors (Light, Phosphorus, and Nitrogen) resulting in eight treatments.ResultsWe found a significant influence of the factor light on fungal community composition, plant biomass, and nutrient accumulation. Departing from a lack of colonization at the initial stage, plants showed a remarkable increment of more than 80% in the arbuscular mycorrhizal fungi (AMF) richness and abundance in their roots when grown under high light conditions, compared with the ones in low light. We also observed an upward trend of C:P and C:N ratios and the above- and belowground biomass production when AMF abundance increased. Furthermore, the compositional analysis of the whole fungal communities associated with S. spicant roots revealed clear differences among low-light and high-light treatments.ConclusionsThis study is the first to investigate the importance of light and nutrient availability in determining fern-AMF relationships. We confirmed that Struthiopteris spicant is a facultative mycorrhizal plant. The composition and diversity of AMF found in the roots of this fern are strongly influenced by light and less by nutrient conditions. Our study shows that ferns respond very sensitively to changes in environmental factors, leading to shifts in the associated mycorrhizal communities.

Blechnum spicant (Blechnaceae) in the Ukrainian flora

The article contains data about the historical and current distribution patterns of Blechnum spicant (Blechnaceae) in Ukraine. This species is quite common in the Carpathian Mountains but is very rare in other regions of Ukraine. Until recently, there were only two known localities of B. spicant in the Western Forest-Steppe (within the Podolian Upland) and only one in Crimea. We discovered one new locality of B. spicant in the Polissian (Polesian) Lowland, in Volyn Region. The article provides phytosociological and topographic data on the Polissian population. This population consists of two sub-populations, which are located not far from each other. Both of them were found in an immature birch-pine forest aged approximately 20 years, in an area of former agricultural lands. We summarise the data on the general distribution of B. spicant in Ukraine. The article also provides phytosociological, biotopic and populational information on localities of B. spicant.

UNDERSTORY RESPONSE TO RESTORATION ALTERNATIVES IN A SEQUOIA SEMPERVIRENS (CUPRESSACEAE) FOREST

The use of mechanical thinning as a restoration tool in second-growth Sequoia sempervirens (D.Don) Endl. forests is becoming increasingly common, yet little is known about how this treatment affects understory plant communities. The shade tolerant herbaceous species common to the Coast Redwood forest are known to be sensitive to disturbance and may provide a metric for assessing the recovery of the plant community as a whole. Stratified random sampling was used to compare understory composition in old-growth reference stands, naturally recovering forests (57–65 years old), and sites treated with variable density thinning (65 years old; 10–12 years post thinning) in Redwood National Park. Pairwise permutational multivariate analysis of variance (PerMANOVA) indicated greater abundance of native herbs, and lower abundance of non-natives, in old-growth and naturally recovering second-growth compared to thinned stands. Non-metric multidimensional scaling suggested that un-thinned sites were more similar to old-growth than thinned sites in regard to understory composition and abundance, and indicator species analysis returned a suite of indicator species shared between naturally recovering plots and old-growth plots (Pteridium aquilinum (L.) Kuhn; Trillium ovatum Pursh; Dryopteris arguta (Kaulf.) Maxon; Blechnum spicant (L.) Roth; Vaccinium ovatum Pursh; Gaultheria shallon Pursh; Rubus spectabilis Pursh; Rhododendron macrophyllum D.Don ex G.Don), while thinned plots shared only one indicator species with old-growth (Goodyera oblongifolia Raf.). In addition, both old-growth and naturally recovering un-thinned second-growth sites were dominated by residual species, while thinned plots were dominated by invader species.

Understory evapotranspiration rates in a coast redwood forest

AbstractIn forests where the overstorey canopy has been disturbed by timber harvest or other means, evapotranspiration (ET) by the understorey may be the main flux of water back to the atmosphere. However, little research has been apportioned to directly measuring understorey water use, and the technology to do so is thus limited. Here, we used a portable chamber to quickly and directly measure understorey ET by measuring the water flux from the soil and vegetation enclosed by the chamber. This method was used in a third‐growth coast redwood forest to measure ET rates from individuals of five species commonly found in the understorey: Sequoia sempervirens (coast redwood) sprouts, Notholithocarpus densiflorus (tanoak) sprouts, Vaccinium ovatum (evergreen huckleberry) sprouts, Polystichum munitum (sword fern) and Struthiopteris spicant (deer fern). Measurements were conducted in four small watersheds which were harvested to varying intensities ranging from 0% to 75% targeted reduction in preharvest overstory basal area. Mean understorey ET rate was highest in the watershed with the lowest residual basal area (x̅ = 0.036 ± 0.024 mm/h) and lowest in the unharvested control watershed (x̅ = 0.013 ± 0.0078 mm/h). Multiple regression modelling on resprouting species indicated that the difference in ET rate between watersheds was related to soil and light resources. These results imply that understorey water use can be significant, particularly in harvested watersheds, and should be quantified at the landscape scale.

Correction to: The Struthiopteris spicant (Blechnaceae, Polypodiopsida) complex in Western Europe, with proposals for taxonomic and nomenclatural changes

Due to an unfortunate error, the citation of the holotype specimen for the new taxon Struthiopteris spicant var. pradae is incorrectly stated as MACB 10654, when it should be MACB 110654.

The Struthiopteris spicant (Blechnaceae, Polypodiopsida) complex in Western Europe, with proposals for taxonomic and nomenclatural changes

Struthiopteris spicant is a medium-sized, dimorphic fern that occurs mainly in Western Europe and Western North America. The species is quite variable, with several forms differing in frond sizes and degree of dimorphism. In addition to the typical plant, in Europe two other varieties are recognized: the Iberian S. s. var. homophyllum includes plants up to 20 cm, monomorphic or subdimorphic, with fragmented cenosori; the Icelandic S. s. var. fallax comprises very small plants up to 5 cm, monomorphic, with isolated sori. Outstanding questions remain about hybridization among the different forms, their taxonomic status, and the relations between different populations. The present work aims to study additional morphological and anatomical features of the S. spicant complex in Western Europe using a statistical approach, to resolve the taxonomic position of the different forms. We observed traits ranging from the rhizome scales to the spores and used one-way ANOVA to test for significant differences between all varieties and PCA to determine whether plants assigned to different varieties can be classified statistically into distinct groups. We detected significant differences in several of the analysed traits among the varieties in the complex. Qualitative differences in pinna anatomy and epidermal cells also help segregation of the varieties considered. Our results allowed us to propose a new specific status for the Icelandic endemic var. fallax and a new endemic Spanish variety, S. s. var. pradae.

Typification of Blechnum spicant var. fallax Lange (Blechnaceae)

<em>Blechnum spicant</em> var. <em>fallax</em> Lange is a fern taxon endemic to Iceland where it occurs in the vicinity of hot springs on geothermally heated soils. The taxon was first described by a Danish botanist Johan Martin Christian Lange in 1880 on the basis of plant material collected by Christian Grønlund in Iceland. Because its holotype was not designated in the protologue, we examined the extant original material including illustrations from <em>Flora Danica</em> and a single plant on sheet C10021769 (deposited in C) that was the basis for the respective plate. We select this specimen as the lectotype of <em>Blechnum spicant</em> var. <em>fallax</em>.

New combinations in Struthiopteris spicant for the European flora

Delimitation of genera in Blechnaceae Newman (1844: 8), a subcosmopolitan fern family with ca. 250 species, has remained uncertain for a long time. During the last decade, evidence has been accumulating about the polyphyletism within Blechnum Linnaeus (1753: 1077) (e.g. Shepherd et al. 2007, Rothfels et al. 2012, Gabriel y Galán et al. 2013, Perrie et al. 2014). Recent molecular studies (Gasper et al. 2016a) lead to an updated classification attempting to put morphological characters into a natural, phylogenetic relation (Gasper et al. 2016b). Because of these changes, the species most people associate with the genus Blechnum, B. spicant (Linnaeus 1753: 1066) Roth (1794: 56), is now treated under Struthiopteris Scopoli (1754: 25).

Proteomic approaches to sexual development mediated by antheridiogen in the fern Blechnum spicant L.

This report is intended to compare proteomic profiles between female and male gametophytes of Blechnum spicant L. For this purpose, female gametophytes were obtained from spores germinated on Murashige and Skoog medium (1962), and the male ones by culturing 30-day-old gametophytes on the same medium supplemented with extract derived from mature gametophytes, which exhibits anteridiogen effect. Proteins were extracted using the phenolic method, and after two-dimensional gel electrophoresis, 581 spots were detected in Coomassie stained gels within the 3-11 pH range and 10-100 kDa Mr ranges. Quantitative and qualitative differences in spot intensity between both types of gametophytes were found. The induction of male gametophytes by antheridiogens was correlated to a global increase in stress and defence-related pathways, which affect flavonoid signaling and cell division, while reducing protein biosynthesis, photosynthesis, and other energy-related pathways, reflecting how stressed are the gametophytes during the induction process. This is the first proteomic study that examines proteins associated to sexual development in the gametophyte of the fern B. spìcant.

Mating System inBlechnum spicantandDryopteris affinisssp.affinisCorrelates with Genetic Variability

The monilophytes Blechnum spicant (L.) Sm. and Dryopteris affinis ssp. affinis (Lowe) Fraser-Jenkins show different reproductive strategies under in vitro conditions. While B. spicant exhibits asexual and sexual reproduction, with an antheridiogen system promoting outcrossing, D. affinis ssp. affinis reproduces only asexually through apogamy. Individuals of several populations of these species, collected in Principado de Asturias (Spain), were analyzed to test the influence of their mating system in the genetic variability displayed by each species. This study shows that the genetic diversity assessed in populations of each species collected in situ is in concordance with that expected according to their reproductive system previously observed in vitro. The genetic diversity found in D. affinis ssp. affinis was low and most of genetic variation can be attributed to differences among localities. This result indicates high fixation of the detected alleles within each locality, as expected for a clonal reproductive system. In the sexual species B. spicant the genetic diversity was higher. Our results confirm the importance of reproduction system in the genetic diversity present in populations of these fern species making essential to consider the definition and study of reproductive system and the associated consequences in the design of successful conservation actions.

Biodiversity of Volatile Organic Compounds from Five French Ferns

Five French ferns belonging to different families were investigated for volatile organic compounds (VOC) by GC-MS using organic solvent extraction. Fifty-five VOC biosynthesized from the shikimic, lipidic and terpenic pathways including monoterpenes, sesquiterpenes and carotenoid-type compounds were identified. The main volatile compound of Adiantum capillus-veneris L. (Pteridaceae) was (E)-2-decenal with a plastic or "stink bug" odor. The volatile profiles of Athyrium filix-femina (L.) Roth (Woodsiaceae) and Blechnum spicant (L.) Roth (Blechnaceae) showed similarities, with small amounts of isoprenoids and the same main volatile compounds, i.e., 2-phenylethanal (odor of lilac and hyacinth) and 1-octen-3-ol (mushroom-like odor). The main volatile compound of Dryopteris filix-mas (L.) Schott (Dryopteridaceae) was (E)-nerolidol with a woody or fresh bark note. Polyketides, as acylfilicinic acids, were mainly identified in this fern. Oreopteris limbosperma (Bellardi ex. All.) J. Holub (Thelypteridaceae), well-known for its lemon smell, contained the highest biodiversity of VOC. Eighty percent of the volatiles was issued from the terpenic pathway. The main volatiles were (E)-nerolidol, alpha-terpineol, beta-caryophyllene and other minor monoterpenes (for example, linalool, pinenes, limonene, and gamma-terpinen-7-al). It was also the fern with the highest number of carotenoid-type derivatives, which were identified in large amounts. Our results were of great interest underlying new industrial valorisation for ferns based on their broad spectrum of volatiles.

Phytosociology and phytogeography of fragmented Alnus glutinosa forests in a Tyrrhenian district (Central Italy)

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.

Protected plant species of forest, lakes and peatbogs in the Western Part of the Drawskie Lakeland

Protected plant species of forest, lakes and peatbogs in the Western Part of the Drawskie Lakeland A floristic study of forest communities, lakes, and peatbogs of the western part of the Drawskie Lakeland was carried out in 2006-2008. The study revealed the presence of numerous valuable plant species. More than 400 floristic lists were compiled. Plant surveys were conducted with the aid of the ATPOL square grid system. To increase the accuracy of the surveys, the basic ATPOL squares (10x10 km) were additionally subdivided into smaller ones of 1x1 km. The area of study was found to support 416 plant species, including protected ones: 17 species strictly protected (e.g., Blechnum spicant, Dactylorhiza incarnata, Drosera rotundifolia, Lycopodium annotinum, Utricularia intermedia) and 12 under partial protection (e.g., Frangula alnus, Menyanthes trifoliata, Ononis spinosa, Ribes nigrum, Viburnum opulus). The list of protected plants contains one species (Lobelia dortmanna) included in the Polish Red Book of Plants.

Flora and vegetation in the catchment area of the stream “La Bolza” in the Merse valley (Siena, southern Tuscany)

Summary This study illustrates the results of a floristic and phytosociological study conducted in a small portion (375 ha) of the Merse valley. Following a brief description of the geomorphologic and climatic aspects, the bryological and vascular flora is presented, obtained through floristic field studies and bibliographic data. The bryological flora includes 25 moss species including Sphagnum subnitens and S. capillifolium, which are of interest from a conservationist viewpoint, and 5 liverworts; the vascular flora comprises 252 species (belonging to 68 families and 186 genera); there are only three endemic entities but many species considered as rare or of interest, including Anagallis minima, Blechnum spicant, Carex viridula, Dryopteris dilatata, Erythronium dens-canis, Juncus bulbosus, Osmunda regalis and Radiola linoides, thus highlighting the phytogeographical relevance of this biotope. Chorological analysis highlighted the dominance of eurosiberian and boreal elements. The principal vegetation types sampled can be ascribed to the following alliances: Cicendio filiformis-Solenopsion laurentiae (Isoetetalia, Isoeto-Nanojuncetea), Osmundo-Alnion and Alnion incanae (Populetalia albae, Querco-Fagetea), Erythronio dens-canis-Quercion petraeae and Teucrio siculi-Quercion cerridis (Quercetalia-pubescen- ti-petraeae, Querco-Fagetea), Sarothamnion scoparii (Cytisetalia scopario-striati, Cytisetea scopario-striati). There are three habitats of Community interest: alluvial forests with Alnus glutinosa (code 91EO), woods of Castanea sativa (code 9260) and rare short-lived small coenoses of Isoeto-Nanojuncetea (code 3130).

The effect of cytokinins on growth and sexual organ development in the gametophyte of Blechnum spicant L.

In this study, we report the role of exogenous and endogenous cytokinins on growth and sexual organ development in the fern Blechnum spicant L. Spore-derived gametophytes (SG) were cultured in full-strength Murashige and Skoog (1962) liquid medium supplemented with (a) 4.44 μMN6-benzyladenine (BAP), (b) a crude extract from mature female gametophytes, and (c) 4.44 μM BAP in combination with the crude extract from mature gametophytes, respectively. Both BAP and the crude extract delayed the gametophyte development, and this effect was increased when they were added together. With respect to sexual organ development, BAP inhibited the sexual organ formation, while the crude extract favored antheridia formation; however, when added together, the percentage of antheridia decreased. The endogenous level of the cytokinins cis-zeatin (cZ), cis-zeatin-riboside (cZR), dihydrozeatin (DHZ), dihydrozeatin riboside (DHZR), isopentenyl adenine (iP), isopentenyl adenosine (iPR), isopentenyl-9-glucoside (iP9G), trans-zeatin (tZ), and trans-zeatin riboside (tZR) were analyzed in female and male gametophytes of B. spicant L. The endogenous levels of cytokinins tZ, cZ, DHZ, cZR, iP, and iPR were higher in female gametophytes than in male gametophytes, with the endogenous iP and iPR content being increased more than 300 and 400 times, respectively.

Effort to reconstruct past population history in the fern Blechnum spicant

Our aim was to evaluate the potential of existing herbarium collections in reconstructing the past population history of the rediscovered clone of the regionally extinct Blechnum spicant by comparing it with herbarium material from previous sites of occurrences in Finland and elsewhere in northern Europe, as well as to reveal the genetic and geographic relationship among the samples. We detected a total of nine polymorphic sites within the three sequenced regions, two SCAR markers developed now for B. spicant and the chloroplast trnL-trnF spacer, totalling 763 bp. Despite low variability, the phylogeographic analysis revealed the presence of some geographic pattern among the samples, of which all except one represented herbarium samples of up to 100 years of age. The rediscovered clone of B. spicant proved to represent the prevalent genotype occurring in northern Europe. The studied sequences were neutral in terms of evolution. It is apparent that existing herbarium collections are useful resources for a range of evolutionary and population studies.

The rust fungi (Uredinales) on ferns in South Africa

The rust fungi (Uredinales, basidiomycota) occuring on ferns (Pteridophyta) in South Africa are described, illustrated and keyed out. All species belong to the pucciniastraceous genera Milesina (M. blechni), Uredinopsis (U. pteridis) or to the related uredinial anamorph genus Milesia (M. nervisequa, M. cf. magellanica, M. silvae-knysnae). Milesia silvae-knysnae on Polystichum pungens is new to science; it probably belongs to the teleomorph genus Milesina. Milesina blechni is reported from South Africa for the first time on the new hosts Blechnum punctulatum and Rumohra adiantoides; it has hitherto been known only from the Northern Hemisphere on Blechnum spicant. Rust specimens collected on Asplenium aethiopicum and A. rutifolium were tentatively assigned to Milesia magellanica which has been known so far only from southern Chile. Hyalopsora neocheilanthis, Milesina neoexigua and M. neovogesiaca are proposed as new names for Hyalopsora cheilanthis, Milesia exigua and M. vogesiaca. It is discussed that the pucciniastraceous fern rusts could have reached South Africa either by migration (M. blechni) or by long-distance air dispersal. In the absence of their gametophyte hosts, species of Abies (Pinaceae), the rusts have to propagate in South Africa by urediniospores infecting fern to fern.

Gibberellins and antheridiogen on sex in Blechnum spicant L.

The role of gibberellins (GAs) in determining sex in the gametophyte of the fern Blechnum spicant L. was studied through (a) the effect of exogenous GA(4+7) and GA3 (b) quantitation of the endogenous levels of GA1, GA3, GA4, GA7, GA9, and GA20 in male and female gametophytes, and (c) the effect of flurprimidol, a GAs biosynthesis inhibitor of the steps of oxidation of ent-kaureno to ent-kaurenoic acid. Our results show that GA(4+7) had a slight effect of inducing either male or female sexual organs, antheridia and archegonia, respectively. The endogenous GAs content was not significantly different between sexes, but the GA4, GA7, and GA20 levels were raised above those of the other GAs in both sexes. Neither antheridiogen biosynthesis nor antheridia formation was inhibited by flurprimidol. Gametophytes regenerated from homogenized mature gametophytes (HG) show a different physiological behavior than spore-derived gametophytes. In the first case, gametophytes are males and synthesize antheridiogen before they attain maturity, in contrast to what occurs in spore-derived gametophytes which are females and synthesize antheridiogen when mature.

Growth and gender in the gametophyte of Blechnum spicant L

The growth and gender in the gametophyte of Blechnum spicant L. were strongly affected by its origin, spore or mature homogenized gametophytes, and also by the addition of plant growth regulators to the culture medium. Spore-derived gametophytes cultured in Murashige and Skoog liquid medium were females and heart-shaped, whereas those derived from mature homogenized gametophytes were shorter and male or asexual (1:3) because of the release of antheridiogen to the culture medium. In the latter, maleness was especially increased by the addition of BA. This cytokinin is a strong inductor of maleness in homogenized cultures; however, even though BA influenced sexual organ formation in spore-derived gametophytes, it does not change the␣female sexual pattern that these gametophytes have. Separate male and female populations of gametophytes were obtained in this work.