Search Results (34)

The quantity, quality, and accumulation rate of plant litter play a key role in forest floor flammability and, by extension, fire regimes. The varying foliage properties of different tree species also determine litter’s decomposition and its accumulation on the forest floor. The removal of litter by soil fauna, i.e., bioturbation, depends on both the dominant tree species and the successional stage of the forest stand. This research involved laboratory mesocosm experiments aiming to determine the effects of litter quality and earthworm activity on the flammability of the forest floor material at different successional ages. The mesocosms simulated the planting of four tree species (the broadleaf species Alnus glutinosa (L.) Gaertn. (Black alder) and Quercus robur L. (English oak) and the conifers Picea omorika (Pančić) Purk. (Serbian spruce) and Pinus nigra J.F. Arnold (Austrian pine)) at a reclamation site near Sokolov (NW Czechia). The mesocosms contained litter from these different tree species, placed directly on overburden soil (immature soil) or on well-developed Oe and A layers (mature soil), inoculated or not inoculated with earthworms, and incubated for 4 months. The surface material in the mesocosms was then subjected to simulated burn events, and the fire path and soil temperature changes were recorded. Burn testing showed that litter type (tree species) and soil maturity significantly influenced flammability. Pine had longer burning times and burning paths and higher post-burn temperatures than those of the other tree species. The immature soil with earthworms had significantly shorter burning times, whereas in the mature soil, earthworms had no effect. We conclude that earthworms have a significant, immediate effect on the litter flammability of immature soils. Full article

Rehmannia glutinosa (RG), a fundamental herb in traditional Chinese medicine belonging to the Orobanchaceae family, has been widely used for centuries due to its diverse therapeutic properties, including promoting blood circulation, enhancing immunity, managing diabetes, reducing inflammation, and supporting kidney function. Despite its traditional significance, scientific studies on RG’s therapeutic mechanisms remain limited, and its underlying pharmacological pathways are not extensively elucidated. This study employed network pharmacology and molecular docking to identify RG’s active compounds and investigate their therapeutic potential in allergy, anemia, diabetes, and menopause. From an initial pool of 122 compounds, 50 bioactive compounds were screened based on bioavailability and drug-likeness, resulting in 40 active compounds and 11 target proteins closely associated with these conditions. Key active compounds identified included iridoid glycosides (rehmaglutin A, B, C, D, jioglutin A, B, C, jioglutolide) and other bioactive molecules such as caffeic acid, geraniol, 5-hydroxytryptamine, melatonin, and rhodioloside. Molecular docking technology was employed to verify the stable binding of target proteins with active compounds. Protein–protein interaction (PPI) analysis revealed that RG’s core target proteins are central to pathways regulating inflammation, cell survival, apoptosis, and immune response. Enrichment analyses demonstrated that RG’s target proteins intersect significantly with pathways including the AGE-RAGE signaling pathway in diabetic complications, IL-17, HIF-1 signaling, and neuroactive ligand-receptor interactions, all of which are essential in managing diabetes and menopause symptoms. These findings underscore RG’s multi-target therapeutic potential, particularly in modulating immunity, metabolism, and inflammation. This study highlights RG’s potential as a therapeutic agent and provides a framework for future research to further elucidate its mechanisms and support the development of targeted drugs based on RG’s active compounds. Full article

The priority habitat 91E0*, consisting of alluvial forests with Alnus glutinosa (L.) Gaertn. and Fraxinus excelsior L., represents a vital ecosystem along Europe’s riverbanks and floodplains. In Greece, the alluvial forests of the Nestos Delta are particularly notable for their unique composition and ecological importance. The present study aimed to assess woody species’ regeneration status and diversity in the priority habitat 91E0* in Nestos, Greece. In the studied area, 13 plant species belonging to 12 genera from 10 families were recorded. The most numerous families were Salicaceae (23.07%) and Moraceae (15.38%). The regeneration index (IR) for Amorpha fruticosa L. and Acer negundo L. exhibited a substantial decline, decreasing from 31.75 and 21.12 cm m⁻² to 2.07 and 2.6 cm m⁻², respectively. This intervention created space for expanding native tree species such as Cornus sanguinea L., Morus alba L., and Populus alba L. The results demonstrate that the regeneration of P. alba L. is currently the most extensive (31.1%) in the alluvial forest, with C. sanguinea L., M. alba L., and A. glutinosa (L.) Gaertn. also showing significant regeneration. In contrast, the regeneration of F. angustifolia Vahl remains very limited (0.21 cm m⁻²), indicating the necessity for targeted restoration efforts. Full article

Ethnographic sources from Finland and Estonia in the 18th to early 20th centuries often mention alder bark as a dye source. The bark of grey alder (Alnus incana) and black alder (Alnus glutinosa) was used to dye wool and linen yarns reddish, paint leather red, and darken linen fishing nets. These recipes were simple folk craft and are not represented in dye books. Combining various sources, a selection of ethnographic and historical recipes was reconstructed through dyeing experiments to deepen the knowledge of alder bark dyeing practices and to recreate a colour palette based on past recipes. To understand the properties of the alder bark dye, the dyed textile samples were tested according to the ISO standards for washing, rubbing, and light fastness, and colour was recorded with the CIELab values. Our results show that it was possible to obtain different shades of brown, reddish brown, and dark brown. The colour fastness of dyed wool samples was moderate or good. Slight colour changes in the washed samples compared to the untreated ones were observed, which can be due to the standard’s heavily alkaline detergent. Full article

Retinal ischemic disorders present significant threats to vision, characterized by inadequate blood supply oxygen–glucose deprivation (OGD), oxidative stress, and cellular injury, often resulting in irreversible injury. Catalpol, an iridoid glycoside derived from Rehmannia glutinosa, has demonstrated antioxidative and neuroprotective effects. This study aimed at investigating the protective effects and mechanisms of catalpol against oxidative stress or OGD in vitro and retinal ischemia in vivo, focusing on the modulation of key biomarkers of retinal ischemia, including HIF-1α, vascular endothelial growth factor (VEGF), angiopoietin-2, MCP-1, and the Wnt/β-catenin pathway. Cellular viability was assessed using retinal ganglion cell-5 (RGC-5) cells cultured in DMEM; a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed. H₂O₂ (1 mM)/OGD was utilized. Vehicle or different catalpol concentrations were administered 15 min before the ischemic-like insults. The Wistar rat eyes’ intraocular pressure was increased to 120 mmHg for 60 min to induce retinal ischemia. Intravitreous injections of catalpol (0.5 or 0.25 mM), Wnt inhibitor DKK1 (1 μg/4 μL), anti-VEGF Lucentis (40 μg/4 μL), or anti-VEGF Eylea (160 μg/4 μL) were administered to the rats’ eyes 15 min before or after retinal ischemia. Electroretinogram (ERG), fluorogold retrograde labeling RGC, Western blotting, ELISA, RT-PCR, and TUNEL were utilized. In vitro, both H₂O₂ and OGD models significantly (p < 0.001/p < 0.001; H₂O₂ and OGD) induced oxidative stress/ischemic-like insults, decreasing RGC-5 cell viability (from 100% to 55.14 ± 2.19%/60.84 ± 4.57%). These injuries were insignificantly (53.85 ± 1.28% at 0.25 mM)/(63.46 ± 3.30% at 0.25 mM) and significantly (p = 0.003/p = 0.012; 64.15 ± 2.41%/77.63 ± 8.59% at 0.5 mM) altered by the pre-administration of catalpol, indicating a possible antioxidative and anti-ischemic effect of 0.5 mM catalpol. In vivo, catalpol had less effect at 0.25 mM for ERG amplitude ratio (median [Q1, Q3] 14.75% [12.64%, 20.48%]) and RGC viability (mean ± SE 63.74 ± 5.13%), whereas (p < 0.05 and p < 0.05) at 0.5 mM ERG’s ratio (35.43% [24.35%, 43.08%]) and RGC’s density (74.34 ± 5.10%) blunted the ischemia-associated significant (p < 0.05 and p < 0.01) reduction in ERG b-wave amplitude (6.89% [4.24%, 10.40%]) and RGC cell viability (45.64 ± 3.02%). Catalpol 0.5 mM also significantly protected against retinal ischemia supported by the increased amplitude ratio of ERG a-wave and oscillatory potential, along with recovering a delayed a-/b-wave response time ratio. When contrasted with DKK1 or Lucentis, catalpol exhibited similar protective effects against retinal ischemia via significantly (p < 0.05) blunting the ischemia-induced overexpression of β-catenin, VEGF, or angiopoietin-2. Moreover, ischemia-associated significant increases in apoptotic cells in the inner retina, inflammatory biomarker MCP-1, and ischemic indicator HIF-1α were significantly nullified by catalpol. Catalpol demonstrated antiapoptotic, anti-inflammatory, anti-ischemic (in vivo retinal ischemia or in vitro OGD), and antioxidative (in vitro) properties, counteracting retinal ischemia via suppressing upstream Wnt/β-catenin and inhibiting downstream HIF-1α, VEGF, and angiopoietin-2, together with its decreasing TUNEL apoptotic cell number and inflammatory MCP-1 concentration. Full article

Rehmannia glutinosa is an important medicinal herb; but its long-term cultivation often leads to continuous cropping problems. The underlying cause can be attributed to the accumulation of and alterations in root exudates; which interact with soil-borne pathogens; particularly Fusarium oxysporum; triggering disease outbreaks that severely affect its yield and quality. It is therefore crucial to elucidate the mechanisms by which root exudates induce F. oxysporum CCS043 outbreaks. In this study; the genome of F. oxysporum CCS043 from R. glutinosa’s rhizosphere microbiota was sequenced and assembled de novo; resulting in a 47.67 Mb genome comprising 16,423 protein-coding genes. Evolutionary analysis suggests that different F. oxysporum strains may adapt to the host rhizosphere microecosystem by acquiring varying numbers of specific genes while maintaining a constant number of core genes.The allelopathic effects of ferulic acid; verbascoside; and catalpol on F. oxysporum CCS043 were examined at the physiological and transcriptomic levels. The application of ferulic acid was observed to primarily facilitate the proliferation and growth of F. oxysporum CCS043; whereas verbascoside notably enhanced the biosynthesis of infection-related enzymes such as pectinase and cellulase. Catalpol demonstrated a moderate level of allelopathic effects in comparison to the other two. Furthermore; 10 effectors were identified by combining the genomic data. Meanwhile; it was found that among the effector-protein-coding genes; ChiC; VRDA; csn; and chitinase exhibited upregulated expression across all treatments. The expression patterns of these key genes were validated using qRT-PCR. Transient overexpression of the two effector-encoding genes in detached R. glutinosa leaves provided further confirmation that ChiC (GME8876_g) and csn (GME9251_g) are key effector proteins responsible for the induction of hypersensitive reactions in R. glutinosa leaf cells. This study provides a preliminary indication that the use of allelochemicals by F. oxysporum CCS043 can promote its own growth and proliferation and enhance infection activity. This finding offers a solid theoretical basis and data support for elucidating the fundamental causes of fungal disease outbreaks in continuous cropping of R. glutinosa and for formulating effective mitigation strategies. Full article

Induced resistance (IR) based on elicitors application aims to strengthen plant defenses, rather than directly targeting pathogens. These compounds are less toxic than conventional pesticides and are useful in reducing their use. Strategies based on COS–OGA, Swinglea glutinosa, and low copper doses were tested in this three-year (2021–2023) field investigation against grapevine downy (DM) and powdery (PM) mildew. Their effectiveness was compared to copper, sulfur, untreated, and water-sprayed plants in a naturally infected vineyard. Combined treatments provided higher levels of protection. COS–OGA at 2 L ha⁻¹ combined with low copper doses and an adjuvant protected canopy and production from both DM and PM at the same level as copper and farm application (based on copper and sulfur). In favorable seasons, 2023 for DM and 2022 for PM, this strategy reduced the DM McKinney Index compared to untreated plants by 74% and 39% on leaves and bunches, respectively. Reductions observed for PM were 85% on leaves and 46% on bunches. S. glutinosa showed reductions only in one assessment against PM on bunches. This work validates IR-based DM and PM management strategies under field conditions and paves the way toward concrete reduction in copper and sulfur use in vineyards. Full article

Alnus glutinosa plays a crucial role in flood control, riverbank stabilization, and water purification. Recognized for its ecological significance, it is listed in the Red Book of Kazakhstan. This study investigated the genetic variability of A. glutinosa populations in Kazakhstan, analyzing 78 trees from seven populations in the Bayanaul mountain forest massif and the northern Turgay regions using 12 SSR markers. The study identified an average of 6.3 alleles and 2.783 effective alleles, as well as observed and expected heterozygosities of 0.570 and 0.562, respectively, reflecting genetic diversity. Among the populations, KS1 (northern Turgay) and PVL3 (Bayanaul) displayed the highest diversity, while PVL5 (Bayanaul) showed slightly lower diversity. The analysis of molecular variance results indicated that 86% of the genetic diversity occurred within populations, with 14% attributed to differences between populations. A UPGMA tree based on Nei’s genetic distance revealed three distinct clusters, suggesting geographically structured genetic variability in A. glutinosa populations. Full article

Background/Objectives: Rehmannia glutinosa, a highly valuable medicinal plant in China, is encountering severe replant disease. Replant disease represents a complex stress driven by multiple principal factors (RDFs), including allelochemicals, microbes, and their interactions. miRNAs are recognized as key regulators of plant response to stresses; however, their specific roles within RDFs are not entirely clear. Methods: This study builds six RDF treatments, comprising R. glutinosa continuously planted (SP), normally planted (NP), and NP treated with ferulic acid (FA), Fusarium oxysporum (FO), and a combination of FA with FO (FAFO). sRNA-seq technology was used to identify crucial miRNAs in response to diverse RDFs. Results: In total, 30 sRNA datasets were generated from the SP, NP, FA, FO, and FAFO samples. A total of 160 known and 41 novel miRNAs (RgmiRNAs) were identified in the R. glutinosa genome based on the sRNA database. Abundance analysis revealed that RgmiRNAs in SP exhibited a distinct expression profile in comparison with others. Of these, 124, 86, 86, and 90 RgmiRNAs were differentially expressed in SP, FA, FO, and FAFO compared with NP. Target analysis indicated that RgmiRNAs downregulated in both SP and RDFs impede the organism growth of R. glutinosa. RgmiRNAs upregulated in SP can disrupt root formation and nutrient metabolism, in which, two RgmiR398 were uniquely expressed in SP. It was confirmed to target RgCSD genes. The expression patterns of RgmiR398 and RgCSD indicated that replant disease induces the oxidative damage of R. glutinosa through RgmiR398. Conclusions: RgmiRNA profiling under RDFs provides a theoretical basis for the further clarification of RgmiRNA function in replant disease. Full article

Planting nitrogen-fixing plants in post-mining sites and similar degraded areas is a common approach to speed up soil development and buildup of the nitrogen pool in soil organic matter. The aim of this study was to explore if slower growth of alder seedlings in initial post-mining sites results from adverse soil conditions or lack of microbial symbionts. To address this question, we sampled young soil (age 15 years) and more developed soil (age 70 years) from heaps after coal mining near Sokolov (Czech Republic). Soil samples were sterilized and not inoculated or inoculated with arbuscular mycorrhizal fungi (AMF) or AMF + Frankia, followed by planting with alder (Alnus glutinosa) seedlings germinated and precultured under sterile conditions. The effect of soil age on alder growth appeared to be non-significant. The only significant growth effect was seen with Frankia inoculation, implicating this inoculum as a key factor in later succession in post-mining soils. When the soil was fully inoculated, alder biomass was higher in developed soil supplied with iron (Fe) and phosphorus (P), indicating that iron and phosphorus availability may affect alder growth. In young soil, alder growth was highest with a combination of iron, phosphorus, and sulfur (S), and a positive effect of sulfur in young soil may correspond with a reduced, alkaline soil pH and increased phosphorus and iron availability. Full article

The youcai mosaic virus (YoMV) can infect a diverse array of crop species, such as Raphanus sativus, Brassica napus, Solanum nigrum, and Rehmannia glutinosa, causing substantial economic damage. This study aimed to develop a rapid, sensitive, and economical diagnostic method for YoMV. We successfully expressed and purified the recombinant His-CP^YoMV-YZ protein in E. coli BL21, which was used to immunize New Zealand White rabbits, generating high-titer polyclonal antibodies (PAb-CP^YoMV-YZ). Additionally, a serological-based reverse transcription loop-mediated isothermal amplification (S-RT-LAMP) assay was refined, combining serological and molecular detection techniques to enhance practicality. Utilizing PAb-CP^YoMV-YZ, we developed four techniques for detecting YoMV: Western blot, dot immunoblotting assay, enzyme-linked immunosorbent assay (ELISA), and S-RT-LAMP. YoMV isolates from various regions and hosts were analyzed. The results indicated that PAb-CP^YoMV-YZ was highly effective in detecting YoMV across a range of hosts and isolates from diverse regions. This study fills an important gap in the serological detection of YoMV and provides a practical tool for on-site diagnosis and control of YoMV infection. Full article

This study used the DNA of Bacillus amyloliquefaciens Ba168 as a template to amplify the flagellin BP8-2 gene and ligate it into the fusion expression vector pCAMBIA1300-35S-EGFP after digestion for the construction of the expression vector pCAMBIA1300-EGFP-BP8-2. Next, using Nicotiana benthamiana as receptor material, transient expression was carried out under the mediation of Agrobacterium tumefaciens C58C1. Finally, the transient expression and subcellular localisation of flagellin BP8-2 protein were analysed using the imaging of co-transformed GFP under laser confocal microscopy. The results showed that flagellin BP8-2 was localised in the cell membrane and nucleus, and the RT-PCR results showed that the BP8-2 gene could be stably expressed in tobacco leaf cells. Furthermore, there was stronger antiviral activity against tobacco mosaic virus (TMV) infection in Nicotiana glutinosa than in BP8-2 and ningnanmycin, with an inhibitory effect of 75.91%, protective effect of 77.45%, and curative effect of 68.15%. TMV movement and coat protein expression were suppressed, and there was a high expression of PR-1a, PAL, and NPR1 in BP8-2-treated tobacco leaf. These results suggest that flagellin BP8-2 inhibits TMV by inducing resistance. Moreover, BP8-2 has low toxicity and is easily biodegradable and eco-friendly. These results further enrich our understanding of the antiviral mechanisms of proteins and provide alternatives for controlling viral diseases in agriculture. Full article

Alder yellows (ALY) phytoplasma (16SrV-C) is associated with ALY, a disease of several Alnus (alder) species in Europe and A. rubra in North America. In all affected species, the symptoms are similar. However, latent infections are common. ALY phytoplasma includes different strains which may be occasionally transmitted to grapevines leading to some grapevine yellows diseases. In the current study, visual symptom assessment and PCR-based methods using universal and group-specific phytoplasma primers were used to update and extend knowledge on the occurrence, impact, and genetic diversity of ALY phytoplasma in declining and non-symptomatic A. glutinosa and A. cordata trees in the Basilicata and Campania regions of southern Italy. ALY phytoplasma was detected in 80% of alder trees examined. In symptomatic trees, no other cause of disease was observed. More than half of alder trees that tested phytoplasma-positive proved to be latently infected. A considerable genetic variability was observed among the newly recorded ALY phytoplasma strains in southern Italy in almost of the genes examined. These included 16S rRNA, 16S/23S rDNA spacer region, ribosomal protein rpsV (rpl22) and rpsC (rps3), map, imp, and groEL genes. Eleven new genotypes were identified at map gene sequence level. However, the genetic differences observed were not related to plant host species, geographical origin, and symptoms shown by infected alder trees. Also, this study indicates that ALY phytoplasma is more widespread than previously thought. Full article

Alnus riparian communities are important for ecological stability. Data on Alnus species were gathered from herbaria and literature, revealing that 54.39% of the information refers to Alnus glutinosa, 39.42% to Alnus incana, and 6.18% to Alnus pubescens. This information highlights the widespread occurrence of A. glutinosa and A. incana, as described in distribution maps, contrasting with the more limited range of the hybrid A. pubescens. Principal component analysis (PCA), utilizing standardized factors, was carried out on 217 relevés of the communities of the studied species. In these relevés, we identified a total of 169 plant species, categorized as herbaceous (83%), trees (11%), and shrubs (6%). Three distinct forest communities, Stellario nemorum-Alnetum glutinosae, Alnetum incanae, and Telekio speciosae-Alnetum incanae, emerged from relevé groups. The distribution maps of the three taxa were overlaid on maps of the region’s protected areas, revealing a substantial presence of these taxa within the protected zones. The research aims to highlight the sustainability and conservation importance of Alnus communities in the Romanian Carpathians, to contribute to ongoing conservation efforts and promote the viability and resilience of these ecologically important wetland habitats. Full article

Floral nectar is mainly a reward in the form of food for pollinators. Its composition plays an important role when pollinators choose their food. Several studies have shown that the popularity of flowers with nectar is influenced by the concentration and ratio of sugars. Here, we present the nectar chemical composition with regard to three main sugars and their concentrations in correlation with abiotic factors for the plant species Salvia pratensis L. and Salvia glutinosa L. through their 2023 flowering season. We sampled nectar using microcapillaries at three different times during the day on sites in nature. Our results show that nectar production in both species is the highest at around 12 a.m. The abiotic factor that affects nectar production in both species is the soil temperature, while UVB radiation does not influence nectar production. Air temperature and air humidity affect the nectar production of S. glutinosa, while soil humidity affects nectar production in S. pratensis. The most represented sugar in S. glutinosa nectar is sucrose, while S. pratensis nectar has more glucose and fructose. Our results show that UVB radiation has an effect on the sucrose level, although it does not have any direct effect on nectar productivity. Full article