Coping with extremes: Responses of Quercus robur L. and Fagus sylvatica L. to soil drought and elevated vapour pressure deficit.

Climate change, particularly droughts and heat waves, significantly impacts global photosynthesis and forest ecosystem sustainability. To understand how trees respond to and recover from hydrological stress, we investigated the combined effects of soil moisture and atmospheric vapour pressure deficit (VPD) on seedlings of the two major European broadleaved tree species Fagus sylvatica (FS) and Quercus robur (QR). The experiment was conducted under natural forest gap conditions, while soil water availability was strictly manipulated. We monitored gas exchange (net photosynthesis, stomatal conductance and transpiration rates), nonstructural carbohydrates (NSC) concentration in roots and stomatal morphometry (size and density) during a drought period and recovery. Our comparative empirical study allowed us to distinguish and quantify the effects of soil drought and VPD on stomatal behavior, going beyond theoretical models. We found that QR conserved water more conservatively than FS by reducing transpiration and regulating stomatal conductance under drought. FS maintained higher stomatal conductance and transpiration at elevated VPD until soil moisture became critically low. QR showed higher intrinsic water use efficiency than FS. Stomata density and size also likely played a role in photosynthetic rate and speed of recovery, especially since QR with its seasonal adjustments in stomatal traits (smaller, more numerous stomata in summer leaves) responded and recovered faster compared to FS. Our focal species showed different responses in NSC content under drought stress and recovery, suggesting possible different evolutionary pathways in coping with stress. QR mobilized soluble sugars, while FS relied on starch mobilization to resist drought. Although our focal species often co-occur in mixed forests, our study showed that they have evolved different physiological, morphological and biochemical strategies to cope with drought stress. This suggests that ongoing climate change may alter their competitive ability and adaptive potential in favor of one of the species studied.

Investigating the impact of temperature on growth rate of the root rot fungus, Gymnopus fusipes.

Gymnopus fusipes is an understudied root rot pathogen associated with multiple tree species and is linked to episodes of oak decline across the United Kingdom and Europe. Although the reported distribution of G. fusipes is broad, many observations rely solely on visual identification of fruiting bodies, which can be unreliable, and lack confirmation by molecular and/or isolation data to verify this broad ecological range. Given the paucity of information regarding the true ecological distribution of G. fusipes, it is difficult to predict and model the potential distribution of the species under both current and future climate scenarios. In this study, to determine the growth capabilities of G. fusipes across a range of ecologically relevant temperatures, five geographically diverse isolates of G. fusipes were grown at five different temperatures ranging from 4-37°C, to determine the optimal temperature for G. fusipes growth, and to establish whether geographically diverse isolates exhibit local adaptation to temperature tolerance. Incubation temperature had a significant effect on G. fusipes growth rate, with 25°C representing the optimum (P<0.001). Isolates had differing growth rates at each of the temperatures, with an isolate from the UK having the highest overall growth rate across all five temperatures tested (P<0.001), and at the optimum, increased by a mean value of over 4915 mm2. Local adaptation to temperature tolerance was not found in the isolates tested. These data demonstrate the optimal incubation temperature for future laboratory studies on G. fusipes and provide the first data on the growth rate of this pathogen across ecologically relevant climate ranges that may inform land managers, modellers, and policy makers in predicting the current and potentially future geographical limits of this widespread root rot pathogen.

A large-scale assessment of eastern whip-poor-will (Antrostomus vociferus) occupancy across a gradient of forest management intensity using autonomous recording units.

Conservationists spend considerable resources to create and enhance wildlife habitat. Monitoring how species respond to these efforts helps managers allocate limited resources. However, monitoring efforts often encounter logistical challenges that are exacerbated as geographic extent increases. We used autonomous recording units (ARUs) and automated acoustic classification to mitigate the challenges of assessing Eastern Whip-poor-will (Antrostomus vociferus) response to forest management across the eastern USA. We deployed 1263 ARUs in forests with varying degrees of management intensity. Recordings were processed using an automated classifier and the resulting detection data were used to assess occupancy. Whip-poor-wills were detected at 401 survey locations. Across our study region, whip-poor-will occupancy decreased with latitude and elevation. At the landscape scale, occupancy decreased with the amount of impervious cover, increased with herbaceous cover and oak and evergreen forests, and exhibited a quadratic relationship with the amount of shrub-scrub cover. At the site-level, occupancy was negatively associated with basal area and brambles (Rubus spp.) and exhibited a quadratic relationship with woody stem density. Implementation of practices that create and sustain a mosaic of forest age classes and a diverse range of canopy closure within oak (Quercus spp.) dominated landscapes will have the highest probability of hosting whip-poor-wills. The use of ARUs and a machine learning classifier helped overcome challenges associated with monitoring a nocturnal species with a short survey window across a large spatial extent. Future monitoring efforts that combine ARU-based protocols and mappable fine-resolution structural vegetation data would likely further advance our understanding of whip-poor-will response to forest management.

Evaluation of the Colonization of Plants from Five Quercus Taxa Native to Greece by Tuber aestivum (Ascomycota, Pezizales).

Fungi of the genus Tuber are famous for their hypogeous ascomata (truffles), many of which possess noteworthy organoleptic properties. T. aestivum shows a wide geographic distribution, has many plant symbionts and is well adapted to various climatic conditions. In this study, five Quercus taxa native to Greece (i.e., Q. coccifera, Q. ilex, Q. ithaburensis subsp. macrolepis, Q. pubescens and Q. trojana subsp. trojana) were inoculated with spore suspensions obtained from a single ascoma of T. aestivum. The fungal colonization of oak roots was evaluated at three, seven and 12 months after inoculation; the respective colonization rates for each time period were as follows: low to medium (17-41%) for Q. pubescens, Q. ithaburensis subsp. macrolepis and Q. trojana subsp. trojana, medium to relatively high (58-80%) for Q. ithaburensis subsp. macrolepis, Q. ilex, Q. pubescens and Q. trojana subsp. trojana, and medium to high (45-87%) for all oak species examined. Positive correlations were assessed between the number of colonized root tips and the total root tips number, but no significant differences were detected between the inoculated plants and the respective control as regards plant growth. The ectomycorrhizae formed by T. aestivum with Q. ithaburensis subsp. macrolepis and Q. trojana subsp. trojana are described for the first time. The outcome of the study evidences the feasibility of generating the seedlings of various indigenous oak species (covering a large range of diverse habitats) successfully inoculated with autochthonous truffles to be readily used for cultivation purposes.

A Strategy for Studying Epigenetic Diversity in Natural Populations: Proof of Concept in Poplar and Oak.

These last 20 years, several techniques have been developed for quantifying DNA methylation, the most studied epigenetic marks in eukaryotes, including the gold standard method, whole-genome bisulphite sequencing (WGBS). WGBS quantifies genome-wide DNA methylation but has several inconveniences rendering it less suitable for population-scale epigenetic studies. The high cost of deep sequencing and the large amounts of data generated prompted us to seek an alternative approach. Restricting studies to parts of the genome would be a satisfactory alternative had there not been a major limitation: the need to select upstream targets corresponding to differentially methylated regions (DMRs) as targets. Given the need to study large numbers of samples, we propose a strategy for investigating DNA methylation variation in natural populations, considering the structural complexity of the genomes with their size and their content in unique as coding regions versus repeated regions as transposable elements. We first identified regions of highly variable DNA methylation in a representative subset of genotypes representative of the biological diversity in the population by WGBS. We then analysed the variations of DNA methylation in these targeted regions at the population level by Sequencing Capture Bisulphite (SeqCapBis). The entire strategy was then validated by applying it to another species. Our strategy was developed as a proof of concept on natural populations of two forest species: Populus nigra and Quercus petraea.

Can mixing Quercus robur and Quercus petraea with Pinus sylvestris compensate for productivity losses due to climate change?

The climate change scenarios RCP 4.5 and RCP 8.5, with a representative concentration pathway for stabilization of radiative forcing of 4.5 W m-2 and 8.5 W m-2 by 2100, respectively, predict an increase in temperature of 1-4.5° Celsius for Europe and a simultaneous shift in precipitation patterns leading to increased drought frequency and severity. The negative consequences of such changes on tree growth on dry sites or at the dry end of a tree species distribution are well-known, but rarely quantified across large gradients. In this study, the growth of Quercus robur and Quercus petraea (Q. spp.) and Pinus sylvestris in pure and mixed stands was predicted for a historical scenario and the two climate change scenarios RCP 4.5 and RCP 8.5 using the individual tree growth model PrognAus. Predictions were made along an ecological gradient ranging from current mean annual temperatures of 5.5-11.4 °C and with mean annual precipitation sums of 586-929 mm. Initial data for the simulation consisted of 23 triplets established in pure and mixed stands of Q. spp. and P. sylvestris. After doing the simulations until 2100, we fitted a linear mixed model using the predicted volume in the year 2100 as response variable to describe the general trends in the simulation results. Productivity decreased for both Q. spp. and P. sylvestris with increasing temperature, and more so, for the warmer sites of the gradient. P. sylvestris is the more productive tree species in the current climate scenario, but the competitive advantage shifts to Q. spp., which is capable to endure very high negative water potentials, for the more severe climate change scenario. The Q. spp.-P. sylvestris mixture presents an intermediate resilience to increased scenario severity. Enrichment of P. sylvestris stands by creating mixtures with Q. spp., but not the opposite, might be a right silvicultural adaptive strategy, especially at lower latitudes. Tree species mixing can only partly compensate productivity losses due to climate change. This may, however, be possible in combination with other silvicultural adaptation strategies, such as thinning and uneven-aged management.

Rhytidome- and cork-type barks of holm oak, cork oak and their hybrids highlight processes leading to cork formation.

BACKGROUND: The periderm is basic for land plants due to its protective role during radial growth, which is achieved by the polymers deposited in the cell walls. In most trees, like holm oak, the first periderm is frequently replaced by subsequent internal periderms yielding a heterogeneous outer bark made of a mixture of periderms and phloem tissues, known as rhytidome. Exceptionally, cork oak forms a persistent or long-lived periderm which results in a homogeneous outer bark of thick phellem cell layers known as cork. Cork oak and holm oak distribution ranges overlap to a great extent, and they often share stands, where they can hybridize and produce offspring showing a rhytidome-type bark. RESULTS: Here we use the outer bark of cork oak, holm oak, and their natural hybrids to analyse the chemical composition, the anatomy and the transcriptome, and further understand the mechanisms underlying periderm development. We also include a unique natural hybrid individual corresponding to a backcross with cork oak that, interestingly, shows a cork-type bark. The inclusion of hybrid samples showing rhytidome-type and cork-type barks is valuable to approach cork and rhytidome development, allowing an accurate identification of candidate genes and processes. The present study underscores that abiotic stress and cell death are enhanced in rhytidome-type barks whereas lipid metabolism and cell cycle are enriched in cork-type barks. Development-related DEGs showing the highest expression, highlight cell division, cell expansion, and cell differentiation as key processes leading to cork or rhytidome-type barks. CONCLUSION: Transcriptome results, in agreement with anatomical and chemical analyses, show that rhytidome and cork-type barks are active in periderm development, and suberin and lignin deposition. Development and cell wall-related DEGs suggest that cell division and expansion are upregulated in cork-type barks whereas cell differentiation is enhanced in rhytidome-type barks.

Do Mesocarnivores Respond to the Seasonality in Management Practices in an Agroforestry Landscape?

In the Mediterranean, we find a mosaic of natural and cultural landscapes, where a variety of forest management practices created intermediate disturbance regimes that potentially increased biodiversity values. Nonetheless, it is essential to understand the species' long-term response to the dynamic management in agroecosystems, since the species tolerance to disturbance can change throughout the life cycle. Mammalian carnivores can be sensitive to human disturbance and are an essential part of ecosystems due to their regulatory and community structuring effects. We investigated the spatial response of five mesocarnivores species to spatially- and temporally- varying management practices in an agroforestry landscape. More specifically, we assessed the mesocarnivores' temporal changes in space use by implementing multi-season occupancy models in a Bayesian framework, using seasonal camera-trapping surveys for a 2-year period. All species had a weak response of local extinction to forestry management and livestock grazing pressure. For forest-dwelling species, occupancy was higher where productivity of perennial vegetation was high, while colonization between seasons was positively associated with vegetation cover. For habitat generalist species, we found that occupancy in the wet season increased with the distance to cattle exclusion plots. Most of these plots are pine stands which are subject to forestry interventions during winter. During the 2-year period we found seasonal fluctuations in occupancy for all species, with an overall slight decrease for three mesocarnivore species, while for the two forest-dwelling species there was an increase in occupancy between years. The weak species response to management practices supports the importance of traditional management for upholding a diverse mesocarnivore community in agroforestry systems but could also reflect these species' ecological plasticity and resilience to disturbance.

Adsorption of Pb, Cu, and Ni Ions on Activated Carbon Prepared from Oak Cupules: Kinetics and Thermodynamics Studies.

Agricultural residue-activated carbon and biochar, inexpensive and environmentally friendly adsorbent materials, have recently received significant research attention. This study investigated the potential use of oak cupules in activated carbon form to remove widespread heavy metals (Pb2+, Cu2+, and Ni2+) from wastewater. The oak-activated carbon was prepared from oak cupules and activated with phosphoric acid. Oak-activated carbon was characterized using FTIR, BET analysis, energy-dispersive X-ray spectrometry (EDS), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The Freundlich, Langmuir, and Temkin isotherm models were used to assess the equilibrium data. The impact of various parameters, including pH effect, temperature, adsorbent dose, and contact time, was estimated. The Freundlich model was the most agreeable with Pb2+ adsorption by oak-based activated carbon, and Langmuir was more compatible with Cu2+ and Ni2+. Under optimum conditions, the average maximum removal was 63% Pb2+, 60% Cu2+, and 54% Ni2+ when every ion was alone in the aqueous solution. The removal was enhanced to 98% Pb2+, 72% Cu2+, and 60% Ni2+ when found as a mixture. The thermodynamic model revealed that the adsorption of ions by oak-based activated carbon is endothermic. The pseudo-second-order kinetic best describes the adsorption mechanism in this study; it verifies chemical sorption as the rate-limiting step in adsorption mechanisms. The oak-activated carbon was effective in removing Pb2+, Cu2+, and Ni2+ from wastewater and aqueous solutions.

Immediate Impacts of Wildfires on Ground-dwelling macroinvertebrate Communities under Stones in Mediterranean Oak Forests.

Wildfires are considered a major disturbance to forest ecosystems in the Mediterranean countries of Southern Europe. Although ground-dwelling macroinvertebrates are crucial to many soil functions, there is a fundamental lack of understanding of how wildfires impact this community in the immediate term and of the role of stones in their survival. Hence, in the present study we assessed the immediate effects of wildfires in the ground-dwelling macroinvertebrate community found under stones by comparing communities in burnt and non-burnt Mediterranean oak forests. Our results revealed that stones allowed the survival of many taxa in the burnt area. However, abundance, richness, diversity, and equitability per stone were significantly lower at the burnt than unburnt sites. Furthermore, the results also showed that richness and abundance increased significantly with increasing stone depth and area, both at the burnt and unburnt sites. Significant changes at the trophic level were observed in the burnt area comparing to the unburnt, particularly a decline in predators. No significant differences were identified concerning habitat associations among taxa. Overall, this study stressed the role of stones as microhabitats and refuge for the ground-dwelling macroinvertebrate community during wildfires.

Oak Leaves as a Raw Material for the Production of Alcoholic Fermented Beverages.

This study aimed to point out the possible use of oak leaves (Q. petraea) in the production of fermented alcoholic beverages. Parameters such as antioxidant capacity, total phenolic content, phenolics and sugars were determined using spectrophotometric and chromatographic methods. pH values were also determined, and in the final product with a fermentation length of 85 days, the alcohol content was determined and sensory analysis performed. The antioxidant capacity of the beverage was lower compared to the infusions before fermentation, and its highest values were recorded in the leaf samples, in which the highest values of phenolic compounds and the total phenolic content were also recorded. A decrease in the content of total phenolics was recorded with the increasing length of fermentation in beverage samples. However, the fermentation process had a positive effect on the contents of some phenolic substances such as catechin, gallic acid and gallocatechin. Sensory analysis showed a higher acceptability of the fermented beverage without the addition of orange, which could be caused by the higher sugar content in these samples. Oak leaves therefore represent a suitable raw material for the production of a fermented alcoholic beverage, without the need to enrich the taste with other ingredients.

De novo transcriptome assembly of the oak processionary moth Thaumetopoea processionea.

OBJECTIVES: The oak processionary moth (OPM) (Thaumetopoea processionea) is a species of moth (order: Lepidoptera) native to parts of central Europe. However, in recent years, it has become an invasive species in various countries, particularly in the United Kingdom and the Netherlands. The larvae of the OPM are covered with urticating barbed hairs (setae) causing irritating and allergic reactions at the three last larval stages (L3-L5). The aim of our study was to generate a de novo transcriptomic assembly for OPM larvae by including one non-allergenic stage (L2) and two allergenic stages (L4 and L5). A transcriptomic assembly will help identify potential allergenic peptides produced by OPM larvae, providing valuable information for developing novel therapeutic strategies and allergic immunodiagnostic assays. DATA: Transcriptomes of three larval stages of the OPM were de novo assembled and annotated using Trinity and Trinotate, respectively. A total of 145,251 transcripts from 99,868 genes were identified. Bench-marking universal single-copy orthologues analysis indicated high completeness of the assembly. About 19,600 genes are differentially expressed between the non-allergenic and allergenic larval stages. The data provided here contribute to the characterization of OPM, which is both an invasive species and a health hazard.

Meta-analysis of livestock effects on tree regeneration in oak agroforestry systems.

Livestock grazing occupies over a quarter of terrestrial land and is prevalent to agroforestry ecosystems, potentially affecting the survival, growth, and density of trees' early developmental stages, such as seeds, seedlings, and saplings. To address the effects of livestock on tree recruitment in the face of ongoing debates about their impacts, we conducted a 33-year meta-analysis in Quercus-dominated agroforestry systems. Our analysis revealed a consistently negative effect of livestock on oak acorns, seedlings, and saplings. Significantly, livestock body size influenced oak regeneration, with small-sized livestock, notably sheep and goats, having a more pronounced negative impact compared to mixed-size systems, mainly involving cattle and sheep. The effects of small-sized livestock were markedly detrimental on acorn survival and seedling/sapling density, although no studies eligible for meta-analysis examined large livestock impacts on acorns. Overall, mixed-size livestock systems, often involving cattle and sheep, lessen the negative effects. Our findings indicate that the body size and foraging behaviors of livestock should be considered for the ecological sustainability of the tree component in agroforestry systems. While protective measures have long been integral to well-managed agroforestry systems, our results underscore the importance of integrating diverse livestock sizes and applying specific protective strategies, particularly for acorns and saplings, to further refine these practices. Future research should expand to underrepresented regions and livestock types to refine global agroforestry management practices.

Dendroremediation of soil contaminated by mining sludge: A three-year study on the potential of Tilia cordata and Quercus robur in remediation of multi-element pollution.

The vast amounts of mining and metallurgical wastes containing unimaginable quantities of toxic metal(loid)s require searching for managed ways. The study aimed to long-term assess the growth, elements accumulation (As, Cd, Hg, In, Mn, Mo, Pb, Sb, Sn, Ti, Tl, Zn) and proline content in 2-year-old Tilia cordata Mill. and Quercus robur L. seedlings growing under 1 and 3% extremely polluted mining sludge (MS) after 1, 2 and 3 years. Both species were able to grow efficiently without significant differences resulting from the impact of MS. The overall rise was higher for T. cordata than for Q. robur. The accumulation ability for As, Hg, In, Mn, Mo, Pb, Ti, and Zn in the whole plant was significantly higher for T. cordata, while Cd, Sb, Sn and Tl did not differ considerably between species. The highest content was found for As, Mn and Zn (68.7, 158, and 157 mg per plant, respectively) for T. cordata after 3 years of growth. The calculated Bioconcentration Factors were the highest for Cu (1.23), In (6.86), and Zn (38.4) for Q. robur, as well as for As (1.55), Hg (3.24), Mn (32.8), Mo (1.64) and Ti (18.0) for T. cordata after 3 years. The highest Translocation Factors were observed for In (1.35) and Sn (1.25) after 3 years, as well as for Mn (2.72, 3.38, and 3.03 after 1, 2, and 3 years) for Q. robur seedlings. The proline content was higher for Q. robur, regardless of which organ was examined, and the differences increased with the time of the experiment and the amount of MS addition (possibly more sensitive to stress). Young T. cordata seedlings show much greater potential than Q. robur. This is the first time that a demonstration of the high potential of long-living trees in multi-element MS remediation has been described.

Naturally diverse plant communities do not resist invasion by the strong competitor, Microstegium vimineum.

PREMISE: Theory predicts and empirical studies have shown that ecologically manipulated communities with high species diversity are resistant to invasion, but do these predictions and results hold true when applied to highly competitive invaders in natural communities? Few studies of diversity-mediated invasion resistance have measured both invasion resistance and invader impact in the same study. METHODS: We used a two-year field experiment to test: (1) diversity-mediated competitive resistance to patch expansion by the grass, Microstegium vimineum; and (2) the competitive effect of M. vimineum on resident plant diversity. We examined responses of M. vimineum to two native plant density-reduction treatments that had opposite effects on species diversity: (1) reducing species richness via the removal of rare species; and (2) reducing dominance by reducing the density of the dominant resident species. We examined the effects of M. vimineum reduction by pre-emergent herbicide on resident diversity in the second year of the study. RESULTS: Neither rare species removal nor dominant species reduction significantly increased M. vimineum density (relative growth rate). The pre-emergent herbicide dramatically reduced M. vimineum in year 2 of the study, but not most resident plants, which were perennials and indirectly benefited from the herbicide at a more productive site, presumably due to reduced competition from M. vimineum. CONCLUSIONS: Diversity-mediated resistance did not effectively deter invasion by a highly competitive invader. In the case of M. vimineum and at more productive sites, it would appear that nearly complete removal of this invader is necessary to preserve plant species diversity.

Effect of Oak Powdery Mildew on Ascorbate-Glutathione Cycle and Other Antioxidants in Plant-Erysiphe alphitoides Interaction.

Erysiphe alphitoides is a species of powdery mildew responsible for the major foliar disease of oak trees, including Quercus robur. Infection with E. alphitoides leads to a reduction in the growth of the trees and in their ability to survive. This paper reports on the biochemical changes characteristic of defence responses in oak leaves with different infection area sizes, collected in July, August, and September during three growing seasons. The study highlights the effect of E. alphitoides infection on changes in the ascorbate-glutathione cycle, phenolic compound profile, and metal content (mineral distribution). Visible symptoms of pathogen infection appeared gradually in July, but the most intense biochemical plant responses in oak leaves were detected mainly in August and September. These responses included increased ascorbate-glutathione enzyme activities, phenolic compounds, and metal contents. In addition, microscopic analyses revealed a strong fluorescence signal of lignin in the epidermis of pathogen-infected leaves. The involvement of the studied compounds in the basic defence mechanisms of oak against E. alphitoides infection is discussed in the paper.

Soil Parameters and Forest Structure Commonly Form the Microbiome Composition and Activity of Topsoil Layers in Planted Forests.

Soil bacterial communities play a remarkable role in nutrient cycling, significantly affecting soil organic material content, soil fertility, and, in an indirect way, plant succession processes. Conversely, vegetation type influences microbial soil life. The present study compared the bacterial microbiome composition, diversity and catabolic activity profile of topsoil samples collected under three different forest types (a twice-coppiced black locust stand, a young, naturally reforested, and a middle-aged mixed pedunculate oak stand) planted on former arable land in the early 20th century. Diversity indices determined during 16S ribosomal RNA sequencing-based metagenome analysis indicated that the black locust stand had the highest soil bacterial community diversity. At the phylum level, Acidobacteriota, Actinobacteriota, Proteobacteria, Verrucomicrobiota, Bacteroidota, and Gemmatimonadota were the most abundant taxa in the forest soils. Concerning soil parameters, redundancy analysis revealed that pH had the highest impact on bacterial community structure and pH, and soil organic carbon content on the samples' respiration patterns. As for catabolic activity, the recently clearcut oak forest showed the lowest substrate-induced respiration, and citrate was the main driver for the inter-stand variability of microbial activity. Our results confirm that soil parameters and forest type influence the composition and functioning of the soil bacterial microbiome.

Plant Dermatitis.

Plant dermatitis is a common pathology that plagues those who work and recreate in the North American outdoors. The most common plant family to cause dermatitis is the Toxicodendron genus, which includes the plants known by the common names of poison ivy, poison oak, and poison sumac. While mortality is usually quite low for this pathology, the incidence and prevalence of the disease leads to substantial healthcare burden and financial implications across the population. The mainstays of treatment have focused on prevention, corticosteroids, and antihistamines.

Restoration age affects microbial-herbaceous plant interactions in an oak woodland.

In degraded ecosystems, soil microbial communities (SMCs) may influence the outcomes of ecological restoration. Restoration practices can affect SMCs, though it is unclear how variation in the onset of restoration activities in woodlands affects SMCs, how those SMCs influence the performance of hard-to-establish woodland forbs, and how different woodland forbs shape SMCs. In this study, we quantified soil properties and species abundances in an oak woodland restoration chronosequence (young, intermediate, and old restorations). We measured the growth of three woodland forb species when inoculated with live whole-soil from young, intermediate, or old restorations. We used DNA metabarcoding to characterize SMCs of each inoculum treatment and the soil after conditioning by each plant species. Our goals were to (1) understand how time since the onset of restoration affected soil abiotic properties, plant communities, and SMCs in a restoration chronosequence, (2) test growth responses of three forb species to whole-soil inoculum from restoration sites, and (3) characterize changes in SMCs before and after conditioning by each forb species. Younger restored woodlands had greater fire-sensitive tree species and lower concentrations of soil phosphorous than intermediate or older restored woodlands. Bacterial and fungal soil communities varied significantly among sites. Forbs exhibited the greatest growth in soil from the young restoration. Each forb species developed a unique soil microbial community. Our results highlight how restoration practices affect SMCs, which can in turn affect the growth of hard-to-establish forb species. Our results also highlight that the choice of forb species can alter SMCs, which could have long-term potential consequences for restoration success.

Taxonomy and pathogenicity of fungi associated with oak decline in northern and central Zagros forests of Iran with emphasis on coelomycetous species.

Oak decline is a complex disorder that seriously threatens the survival of Zagros forests. In an extensive study on taxonomy and pathology of fungi associated with oak decline in the central and northern part of Zagros forests, 462 fungal isolates were obtained from oak trees showing canker, gummosis, dieback, defoliation, and partial or total death symptoms. Based on inter-simple sequence repeat (ISSR) fingerprinting patterns, morphological characteristics, and sequences of ribosomal DNA (28S rDNA and ITS) and protein coding loci (acl1, act1, caM, tef-1α, rpb1, rpb2, and tub2), 24 fungal species corresponding to 19 genera were characterized. Forty percent of the isolates were placed in eight coelomycetous species from seven genera, namely, Alloeutypa, Botryosphaeria, Cytospora, Didymella, Gnomoniopsis, Kalmusia, and Neoscytalidium. Of these, four species are new to science, which are introduced here as taxonomic novelties: Alloeutypa iranensis sp. nov., Cytospora hedjaroudei sp. nov., Cytospora zagrosensis sp. nov., and Gnomoniopsis quercicola sp. nov. According to pathogenicity trials on leaves and stems of 2-year-old Persian oak (Quercus brantii) seedlings, Alternaria spp. (A. alternata, A. atra, and A. contlous), Chaetomium globosum, and Parachaetomium perlucidum were recognized as nonpathogenic. All coelomycetous species were determined as pathogenic in both pathogenicity trials on leaves and seedling stems, of which Gnomoniopsis quercicola sp. nov., Botryosphaeria dothidea, and Neoscytalidium dimidiatum were recognized as the most virulent species followed by Biscogniauxia rosacearum.