Populus Nigra Research Articles

Modelling Differently Defined Dominant Stand Diameters of Monospecific Forest Plantations

Quadratic mean diameter is a widely used stand parameter present in the stand inventory summaries, while the top stand diameter is rarely reported in the literature, mainly in relation to dominant stand height. Since the dominant stand height is usually determined from the tree height-diameter curve of the stand, it is important how the top tree assemblage, used to estimate dominant diameter, is defined. The main objective of our study was to assess the bias between differently defined dominant diameter estimates for monospecific plantations of various species, to model the dominant diameter as a function of quadratic mean diameter and other relevant stand variables, and to estimate its goodness-of-fit in predicting dominant diameter and dominant height.We used data records gathered in sample plots in monospecific plantations of four tree species: Scots pine, Black pine, black locust and hybrid black poplar. We calculated the quadratic and arithmetic mean diameters of the 20% thickest trees in the plots, and the quadratic and arithmetic mean diameters of the trees, whose number corresponded to the 100 thickest trees per hectare. For each dataset, we analyzed the range and the distribution of the relative deviations calculated for each pair of dominant diameter estimates. For the Black pine plantations, regression models were developed for the two dominant diameter definitions, whose values differed most. Their goodness-of-fit was assessed from model efficiency and error statistics. The same model derivation procedure, applied to the Scots pine data, was followed by substitution of the predicted dominant diameter into a height-diameter model to assess the goodness-of-fit of the dominant height predictions.The differences between the arithmetic and quadratic means, estimated from the same subsample of trees, did not exceed 2% in all cases. However, dominant stand diameters calculated as averages of differently defined largest tree collectives differed by as much as 35%. Regardless of its definition, the dominant stand diameter was adequately predicted by a function of the quadratic mean diameter alone or considering stand basal area as a second predictor. The models showed very good accuracy of model efficiency above 0.92, average absolute error below 8%, with 90% of the relative errors less than 15%. The predicted dominant diameter value can be used in a height-diameter model to estimate with confidence the dominant stand height of a monospecific forest plantation, allowing the forecast of the stand attributes based on dominant trees when only average stand variables are known.

Pollarding May Relieve Drought Stress in Black Poplars

Pollarding has historically been used in broadleaf tree species across European woodlands. However, despite pollarding enhances vigor growth in the short term, it is still unclear how long this effect lasts and whether it can alleviate drought stress in seasonally dry regions. We compared the radial growth and wood δ13C (13C/12C), a proxy of intrinsic water-use efficiency (iWUE), of trees pollarded 10 and 20 years ago in two black poplar (Populus nigra L.) riparian stands located in North Eastern Spain and subjected to different ecohydrological conditions. We also assessed if pollarded trees showed different leaf phenology as compared with uncut trees of coexisting white poplar (Populus alba L.) trees. The relationships between growth, climate variables, drought severity and river flow were quantified. Pollarded and uncut trees showed a similar leaf phenology with a trend towards earlier leaf unfolding as springs become warmer. Pollarding increased growth rates by 54% (ratio between trees pollarded 10 and 20 years ago, respectively), but this enhancement was transitory and lasted ca. 10 years, whereas wood δ13C decreased −5%. The growth of black poplar increased in response to high precipitation in the previous winter, cool wet conditions, and a higher river flow in summer. Pollarding improves growth and relieves drought stress.

Removal of metaldehyde and acetamiprid by extracted cellulose from biomass incorporated with copper after acetylation

The presence of pesticides in water have reached to an alarming level in some parts of the world and have caused deteriorating effects on human health. Reclamation of portable water from such contaminants have become mandatory. Scientists around the world are trying to devise new methods of water purification. The target can be achieved either by limiting the use of pesticides for agriculture purposes or by devising unique methods for their recoveries from contaminated water. In this context, herein cellulose has been extracted from Populus nigra, subjected to acetylation using acetic acid in the acidic medium (sulfuric acid). The modified acetylated cellulose was treated with Cu-based salt to enable the metallic combination. The prepared sorbent was characterized by UV, SEM, EDX, XRD, and FTIR techniques. Two insecticides; metaldehyde and acetamiprid in synthetic waste-water solution were subjected for adsorption on the modified sorbent in a series of experiments to evaluate the impact of contact time, sorbent dosage, pH, and temperature. Optimum conditions established in a series of experiments such as 80 and 60 min of contact time for acetamiprid and metaldehyde respectively, pH of 8 and 9 (slightly basic) correspondingly for the mentioned pesticides, and a 0.08 g adsorbent dosage were used in the estimation of kinetics and isothermal parameters. The kinetic data successfully followed the pseudo-second-order kinetic model whereas, the isothermal data was found to be best fitted by Langmuir isotherm model in the case of acetamiprid and by Freundlich in the case of metaldehyde. The regeneration study was performed for both the pesticides showing more than 70 % removal capabilities of fabricated adsorbent after three consecutive cycles. The prepared adsorbent could be a better alternative of commercial activated carbon however, further experiments are encouraged to investigate the full environmental application spectrum of the fabricated sorbent.

Tissue ontogeny and chemical composition influence bacterial biodiversity in the wood and shoot tip of Populus nigra.

Plant-microbe interactions significantly influence plant growth dynamics and adaptability. This study explores the impact of metabolites on microbial biodiversity in shoot tips and wood of Populus nigra under greenhouse conditions, using high-throughput sequencing and metabolite profiling. Branches from P. nigra were harvested, rooted, and transplanted into pots for growth. After 3 months, tissue samples from shoot tips and wood were collected, and metabolites extracted and analysed using GC-MS and LC-MS. Genomic DNA was extracted and subjected to high-throughput sequencing for bacterial biodiversity profiling. Both datasets were analysed using bioinformatic and statistical pipelines. Metabolite profiling indicated that shoot tips had a higher relative abundance of primary and secondary metabolites, including sugars, fatty acids, organic acids, phenolic acid derivatives and salicinoids, while wood was enriched in flavonoids. Bacterial biodiversity also differed significantly between these tissues, with Clostridiales, Bacteroidales and Bacillales dominating in shoot tips, associated with rapid growth and anaerobic fermentation, while wood tissues were characterized by diazotrophs from Rhizobiales, Sphingomonadales and Frankiales. PCoA clustering confirmed tissue-specific microbial differences. Functional analysis revealed an enrichment of fundamental cellular processes in shoot tips, while wood exhibited pathways related to degradation and mortality. Metabolite profiling revealed significant variations in primary and secondary metabolites, highlighting their influence on microbial biodiversity across plant tissues. The dominance of specific bacterial orders and distinct functional pathways in each tissue suggests a tailored microbial response to the unique environments of shoot tips and wood.

Prediction of surface roughness at the machining of densified wood surfaces

ABSTRACT In this research, modeling and interpretation of the effects of the machining parameters on surface roughness (Rz) using artificial neural networks (ANN) and analysis methods (MLP, LVQ and Taguchi Design analysis) werw studied. Black poplar (Populus nigra) was selected as the experimental material. Specimens, which were transversal densified by a thermo-mechanical (TM) process at 0%, 20% and 40% compression ratios. The densified wood was processed at 1000, 1500 and 2000 mm/min feed speeds and in 12,000, 15,000, and 18,000 rpm rotation speeds in a CNC machine by using two different cutters. Rz surface-roughness values were measured. The modeling of Rz with artificial neural networks (ANN) is discussed. While 97% success was achieved in the classification made with multilayer perceptron (MLP) in estimating Rz, this success rate is 100% in the classification made with learning vector quantization (LVQ). MLP and LVQ are operations in the MATLAB R2019b software. Taguchi values were compared with the experimental data results, it was seen that the MSE value was 4.6%, the MAE value was 1.8%, and the RMSE value was 2.1%. These results showed that the presented models can accurately determine the appropriate parameters for the desired Rz. The prediction results and presented models can be applied for targeted industrial applications.

Improving Carbon Sequestration in Wetlands Using Native Poplar Genotypes for Reforestation Purposes

From the early 2000s, many forestation projects were carried out in the flooding areas of the Po River to preserve abandoned or damaged riverbanks and establish natural populations of Populus nigra L. for species conservation and future seed collection activities. Different clones of P. nigra, belonging to a collection of the Centre for Forestry and Wood (CREA-FL), were planted. The group named ‘POBIA’ comprises 35 selected clones chosen for their survival ability and fast growth. After plantation and a few essential cultural inputs, four establishments were left undisturbed. This study highlights the survival, growth, and performance results of the ‘POBIA’ group compared to other not-selected clones. The ‘POBIA’ clones showed a higher survival than the not-selected clones. Moreover, the ‘POBIA’ groups showed a significantly higher C sink performance in three of four establishments, reaching 278.6 t ha−1 of CO2 obtained in thirteen years in one site. The management of ‘POBIA’ clones in reforestation projects agrees with the EU recommendations for a vital ecosystem service.

Can Multiscale Thermal Infrared Imaging Help Validate and Monitor Water Stress in Alluvial Forests?

ABSTRACTAlluvial forests are sensitive to drought induced by climate change and exacerbated by altered flow regimes. Our ability to detect and map their sensitivity to drought is crucial to evaluate the effects of climate change and adjust management practices. Therefore, we explore the potential of multiscale thermal infrared imagery (TIR) to diagnose their sensitivity to droughts. In summer 2022, we sampled leaves and phloem on Populus nigra trees from two sites with contrasted hydrological connectivity along the Ain River (France) to investigate the seasonality of water stress and act as ground truth for airborne TIR images. To map forest sensitivity to drought, we used TIR data from four airborne campaigns and Landsat archives over a larger spatial and temporal extent. Field data showed that stress conditions were reached for both sites but were higher in the site with lower groundwater connectivity, which was also the case for individual tree crown temperatures. At the forest plot scale, canopy temperature was linked to forest connectivity for two of four TIR campaigns, with higher values in the more degraded reaches. Landsat data were used to locate the areas of the riparian forest impacted by a historical drought event and monitor their recovery and proved useful to identify trends. TIR data showed promising results to help detect and map tree water stress in riparian environments. However, stress is not detected in all TIR campaigns, demonstrating that one‐shot TIR acquisitions alone are not enough to diagnose stress and complementary in‐field eco‐physiological measurements are necessary.

Physical, mechanical, and thermal properties of heat-treated poplar and beech wood

Air-dried density, weight loss (WL), impact bending strength (IBS), Shore-D hardness, and thermal conductivity values were determined for heat-treated poplar (Populus nigra L.) and beech (Fagus orientalis Lipsky) wood and compared with those for untreated samples. The test samples were heat-treated at 140, 160, 180, and 200 °C for 2 h. The results showed that density decreased and WL increased with increasing temperature for all temperatures. Additionally, during the heat treatment, the IBS increased in beech wood samples at 140 °C, but at higher temperatures, these values gradually decreased in both wood species. The highest decline in IBS values, found at a temperature of 200 °C, was 66.5% for beech and 55.7% for poplar. The Shore-D hardness of both wood species increased after heat treatment and regarding beech wood, the hardness increasing rate at temperature at 140 °C, 160 °C, 180 °C and 200 °C, 8.94%, 14.19%, 8.27% and 11.7%, respectively according to control samples. Regarding poplar wood, hardness increasing rates were 6.20% at 140 °C, 4.41% at 160°C, 5.88% at 180°C and 5.31% at 200°C according to control samples. The thermal conductivity of poplar and beech wood samples decreased after heat treatment, except for samples heat treated at 160 °C.

Removal of metaldehyde pesticide from aquatic media using modified cellulose obtained from Populus nigra plant, as potential adsorbent

Abstract In this study modified cellulose based adsorbent was prepared from Populus nigra plant, and used for elimination of metaldehyde (herbicide) from model waste water. The adsorbent was characterized through analytical technique such as FTIR, SEM, EDX and XRD for structural adsorption related parameters. The results of SEM showed the suitability of the material to be used as adsorbent and FTIR showed successful crosslinking of polyvinyl alcohol into cellulose structure. In order to get maximum reclamation benefits from adsorbent it was subjected to a number of tests evaluating the effect of metaldehyde concentration, sorbent dose, contact time, initial pH of solution and temperature. The maximum removal of 70 % was achieved under conditions of 80 mg/L metaldehyde concentration, 60 min contact time, pH of 8, 0.08 g sorbent dosage, and room temperature (25 °C). The Langmuir isotherm model with correlation coefficients of 0.9855 and maximum adsorption capacity recorded was 8.32 mg/g, while excellent agreement was shown by kinetic data with pseudo second order kinetic model with R 2 = 0.9876. Thermodynamic study indicated enthalpy change (ΔH° = −129 kJ/mol) to be negative, entropy change (ΔS° = 161.7 j/mol) positive, and the Gibbs free energy (ΔG) as negative showing that the process to be exothermic and feasible/spontaneous with an increase of randomness at solid liquid interface. The finding indicated that modified cellulose could be used as an efficient adsorbent for removal of metaldehyde from model waste water. However, further validation with other pollutants will be helpful in checking reproducibility of the present findings.

Unraveling the difference of sensitivity to ozone between non-hybrid native poplar and hybrid poplar clones: A flux-based dose-response analysis

Poplars are economically important tree crops and biologically important model plants, which are known to be sensitive to ozone (O3). Although surface O3 is considered as a significant global environmental issue because of its phytotoxicity and greenhouse effect, the knowledge of the dose-response (DR) relationships in poplars for the assessment of O3 risk is still limited. Hence, this study aimed at collecting data of studies with manipulative O3 exposures of poplars within FACE (Free Air Concentration Enhancement) and OTC (Open-Top Chamber) facilities. The datasets contain studies on hybrid poplar clones and a non-hybrid native poplar (Populus nigra L.) reporting both AOT40 (Accumulated exposure Over a Threshold of 40 ppb) and POD1 (Phytotoxic Ozone Dose above a threshold of 1 nmol m−2 Projected Leaf Area [PLA] s−1) to compare exposure- and flux-based indices. As a result, linear regression analysis showed that the flux-based POD1 was better than the exposure-based AOT40 to explain the biomass response of poplars to O3. From the DR relationships, a critical level (CL) of 5.7 mmol m−2 POD1 has been derived corresponding to 4% biomass growth reduction for hybrid poplar clones, which can be considered very sensitive to O3, while the non-hybrid native poplar was less sensitive to O3 (CL: 10.3 mmol m−2 POD1), although the potential risk of O3 for this taxon is still high due to very high stomatal conductance. Moreover, the different experimental settings (OTC vs. FACE) have affected the AOT40-based DR relationships but not the POD1-based DR relationships, suggesting that poplar responses to O3 were principally explained by stomatal O3 uptake regardless of the different experimental settings and exposure patterns. These results highlight the importance of the flux-based approach, especially when scaling up from experimental datasets to the O3 risk assessment for poplars at the regional or global scale.

Artificial Neural Network–based Prediction Model to Minimize Dust Emission in the Machining Process

BackgroundDust generated during various wood-related activities, such as cutting, sanding, or processing wood materials, can pose significant health and environmental risks due to its potential to cause respiratory problems and contribute to air pollution. Understanding the factors influencing dust emission is important for devising effective mitigation strategies, ensuring a safer working environment, and minimizing environmental impact. This study focuses on developing an artificial neural network (ANN) model to predict dust emission values in the machining of black poplar (Populus nigra L.), oriental beech (Fagus orientalis L.), and medium-density fiberboards. MethodsThe multilayer feed-forward ANN model is developed using a customized application built with MATLAB code. The inputs to the ANN model include material type, cutting width, number of blades, and cutting depth, whereas the output is the dust emission. Model performance is assessed through graphical and statistical comparisons. ResultsThe results reveal that the developed ANN model can provide adequate predictions for dust emission with an acceptable level of accuracy. Through the implementation of the ANN model, the study predicts intermediate dust emission values for different cutting widths and cutting depths, which are not considered in the experimental work. It is observed that dust emission tends to decrease with reductions in cutting width and cutting depth. ConclusionThis study introduces an alternative approach to optimize machining-process conditions for minimizing dust emissions. The findings of this research will assist industries in obtaining dust emission values without the need for additional experimental activities, thereby reducing experimental time and costs.

PeHSFA3 is essential for the heat-stress response of Populus × euramericana

Heat shock transcription factors (HSFs) are crucial regulators in the responses of plants to heat stress, but their mechanisms of action in trees are unclear. We identified an HSFA gene, PeHSFA3, in Populus × euramericana (Populus deltoides × Populus nigra), which was highly responsive to heat. Its protein product was in both the cytoplasm and the nucleus. Stably overexpressing PeHSFA3 in poplar enhanced heat tolerance, improved photosynthetic capacity, increased antioxidant enzyme activities, reduced reactive oxygen species (ROS) levels, and upregulated antioxidant-related genes such as SODF2, SODCP, PER46–1, PER46–2, and PER31 under heat stress. Conversely, suppressing the PeHSFA3 gene by Virus-induced gene silencing (VIGS) in Populus × euramericana decreased its heat tolerance. qRT-PCR analysis demonstrated that PeHSFA3 enhances the expression of several heat-protective genes, including small heat-shock protein genes (HSP22C, HSP21–5, HSP18.1, HSP16A, HSP16B, HSP26.5–1, and HSP26.5–2) and ATG8. Transcriptomic analysis suggested that the activation of glutathione metabolic pathways contributes to PeHSFA3-mediated heat tolerance. Our findings reveal that PeHSFA3 mediates resistance to heat stress in poplar and could be used to enhance the thermotolerance of poplar.

A strategy for studying epigenetic diversity in natural populations: proof of concept in poplar and oak.

In the 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 bisulfite 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 as targets. Given the need to study large numbers of samples, we propose a strategy for investigating DNA methylation variation in natural populations, taking into account the structural complexity of genomes, their size, and their content in unique coding regions versus repeated regions as transposable elements. We first identified regions of highly variable DNA methylation in a 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 bisulfite (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.

Use of Spinning Rollers for Surface Densification of Wood

In this study, softwood cedar of Lebanon (Cedrus libani A.Rich.) and hardwood black poplar (Populus nigra L.), turned into cylinders by turning, were subjected to a surface densification process. Densification was carried out on the lathe using the spinning roller designed and manufactured for this purpose. Hardness, brightness and roughness (Rz) measurements were carried out on undensified and densified regions of the cylindrical solid wood materials. An increase in hardness and brightness and a decrease in roughness values occurred under all densification conditions. The highest surface hardness values occurred in cedar of Lebanon at 0.081 mm/rev feed, 200 rpm spindle speed, and 1 mm densification depth. On densified wood surfaces, as the feed from the densification parameters increases, the hardness decreases, and as the densification depth increases, the hardness increases-. The effect of surface densification parameters on the gloss and roughness results of the samples shows no linear effect in terms of experimental parameters. In both species, lower spring back was obtained at low depth of densification.

PRELIMINARY STUDY OF DEPENDENCE OF SMOKE AND CARBON MONOXIDE EMISSION ON HEAT RELEASE RATE FROM FAST-GROWING WOOD SPECIES

The aim of this paper is to create the model for prediction of carbon monoxide release rate (CORR) and smoke production rate (SPR) from heat release rate (HRR) of fast-growing wood species. The model is independent on wood species, thus is suitable for all fast-growing wood species. Three wood species hybrid poplar J-105 (Populus nigra × P. maximowiczii A. Henry), white willow (Salix alba L.) and black locust (Robinia pseudoacacia L.) were used for universal model creation. The heat release rate, smoke production rate and carbon monoxide release rate have been measured at three heat fluxes (25, 35 and 50 kW.m-2) by the cone calorimeter. The average values of CORR and SPR for all investigated wood species were 0.051 g.m-2.s-1 and 0.086 m2.m-2.s-1, respectively. Both dependencies of SPR and CORR on HRR have shown similar trends during the ignition phase (unstable trend) and during the intense burning phase (roughly linear increasing with HRR). The main difference was shown during the steady state phase (dependency of SPR on HRR is stable while dependency of CO on HRR is highly unstable). The results also proved a significant impact of wood density on these dependencies, thus, the neural network for prediction of SPR, CORR from HRR was applied. The coefficients of determination R2 for trained neural networks, for both SPR and CORR, were achieved in the range from 0.96 to 0.97

High-resolution methylome analysis uncovers stress-responsive genomic hotspots and drought-sensitive transposable element superfamilies in the clonal Lombardy poplar.

DNA methylation is environment-sensitive and can mediate stress responses. In trees, changes in the environment might cumulatively shape the methylome landscape over time. However, because high-resolution methylome studies usually focus on single environmental cues, the stress-specificity and long-term stability of methylation responses remain unclear. Here, we studied the methylome plasticity of a Populus nigra cv. 'Italica' clone widely distributed across Europe. Adult trees from different geographic locations were clonally propagated in a common garden experiment and exposed to cold, heat, drought, herbivory, rust infection, and salicylic acid treatments. Whole-genome bisulfite sequencing revealed stress-induced and naturally occurring DNA methylation variants. In CG/CHG contexts, the same genomic regions were often affected by multiple stresses, suggesting a generic methylome response. Moreover, these variants showed striking overlap with naturally occurring methylation variants between trees from different locations. Drought treatment triggered CHH hypermethylation of transposable elements, affecting entire superfamilies near drought-responsive genes. Thus, we revealed genomic hotspots of methylation change that are not stress-specific and that contribute to natural DNA methylation variation, and identified stress-specific hypermethylation of entire transposon superfamilies with possible functional consequences. Our results underscore the importance of studying multiple stressors in a single experiment for recognizing general versus stress-specific methylome responses.

Biomass yield and metal phytoextraction efficiency of Salix and Populus clones harvested at different rotation lengths in the field experiment

BackgroundPhytoextraction belongs to environmentally well-accepted remediation technologies to remove metals from contaminated soils. Due to long-time requirement, sufficient data for proper phytoextraction evaluation are missing. Four clones of fast-growing trees: two willow species (S1), Salix viminalis L. (Salix schwerinii E.L.Wolf × S. viminalis) × S. viminalis) and (S2)—Salix smithiana (Salix × smithiana Willd.), and two poplar clones (P1), Populus Max-4 (Populus nigra L. × Populus maximowiczii A. Henry) and (P2) Wolterson (P. nigra L.) were cultivated under field conditions at medium-to-high Cd and Pb, and low Zn soil contamination to assess trees’ long-term ability of biomass production and removal of potentially toxic elements (PTEs). The biomass yield and PTE uptake were measured during 8 years of regular growth under three rotation lengths: four harvests following 2-year periods (4 × 2y), two harvests in 4-year periods (2 × 4y), and one harvest representing 8 years of growth (1 × 8y).ResultsIn most cases, the highest annual dry biomass yield was achieved with a 2 × 4y rotation (P1 = 20.9 t ha−1 y−1, S2 = 18.4 t ha−1y−1), and the yield decreased in order 2 × 4y > 1 × 8y > 4 × 2y of harvesting periods. Only clone S1 showed a different pattern. The differences in biomass yield substantially affected the PTE phytoextraction. The greatest amount of Cd and Zn was removed by willow S2, with the highest biomass yield, and the strongest ability to accumulate PTEs. With 2 × 4y rotation, S2 removed a substantial amount of Cd (9.07%) and Zn (3.43%) from the topsoil horizon (0–20 cm) and 5.62% Cd and 2.04% Zn from horizon 20–40 cm; phytoextraction rate was slightly lower for 1 × 8y rotation. The poplar P1 removed the most Pb in the 1 × 8y rotation, but the overall Pb phytoextraction was negligible. The results indicated that lignin and cellulose contents increased, and hemicellulose content decreased with increased concentrations of Cd, Pb and Zn in poplars wood.ConclusionsThe data confirmed that phytoextraction over longer harvest periods offered promising results for removing Cd from medium- to high-level contaminated soils; however, the ability of Pb removal was extremely low. The longer harvest period should be more economically feasible.Graphical

Wound healing potential of a formula based on Populus nigra L. flower buds extract with anti-inflammatory activity

Ethnopharmacological relevanceWound healing is a complex and dysnamic process supported by a myriad of cellular events that are tightly coordinated to repair efficiently damaged tissue. Populus nigra L. (Salicaceae) flower buds are traditionally used in the treatment of dermatitis, upper respiratory tract infections, rheumatism and wounds. Aim of the studyThe aim of this study was to assess the wound healing potential of black poplar ointment containing 10 or 20 % of Populus nigra ethanolic flower buds extract using the excision model in rats. Materials and methodsTwo ointments (10 and 20 %) were prepared from Populus nigra flower buds ethanolic extract and topically applied on the area of excised skin of the rats for either 14 or 20 days. Morphological, macroscopic, histological and biochemical parameters were evaluated. ResultsThe results showed that the extract contained high amounts of total phenols (89.5 ± 7.7 mg caffeic acid equivalent/g of extract) and hydrolysable tannins (142.05 ± 2.55 mg tannic acid equivalent/g of extract), in correlation with strong DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity and beta-carotene bleaching with values of 96.31 ± 3.42 and 85.27 ± 1.79 %, respectively. Anti-inflammatory potential was illustrated by lipoxygenase and cyclooxygenase inhibition (52.80 ± 0.2 and 53.88 ± 2.55 %, respectively). Treatment with Populus nigra ointment (10 and 20 %) promoted wound contraction of 97.37 ± 1.19 and 97.28 ± 0.91 %, respectively. The antioxidant marker enzymes, catalase (0.10 ± 0.001; 0.08 ± 0.003 U/mg protein) and superoxide dismutase (363.34 ± 24.37; 317.82 ± 53.83 U/mg protein) activities in the granulation tissues were upgraded with respective treatments of 10 or 20 % ointment. Concurrently, the myeloperoxidase activity (2.21 ± 1.01; 2.13 ± 0.75 U/mg protein) was repressed, indicating anti-inflammatory potential, when compared to untreated, standard and excipient groups. Moreover, a significant increase in respective levels of hydroxyproline (p < 0.001) (28.05 ± 1.20; 25.29 ± 1.17 μg/mg tissue) and hexosamine (p < 0.05) (20.18 ± 1.21; 18.95 ± 1.98 μg/mg tissue) was triggered, reflecting a high regeneration of collagen in the scarred tissue. Histological examination of treated skin tissue revealed higher rates of re-epithelialization, lower neutrophils infiltration and re-vascularization in comparison to the control group. ConclusionGiven that the 10 % ointment was the optimal concentration, our findings offer an efficient drug formula for wound healing.

Sustainable Afforestation Strategies: Hybrid Multi-Criteria Decision-Making Model in Post-Mining Rehabilitation

This article describes an effective approach for selecting suitable plant species for afforestation in post-mining rehabilitation. The research was conducted in the Western Black Sea region of Turkey. The aim of the research is to perform accurate criteria weighting and species prioritization for afforestation in post-mining degraded areas. This helps to ensure consistent conditions for the future use of the site as a forest, sustainability of nature, and selection of appropriate species adapted to the difficult post-mining conditions. In this study, which is a multi-criteria decision-making problem (MCDM), the weights of the criteria were determined by stepwise weight assessment ratio analysis (SWARA), and the priority ranking of the species was determined by the analytic hierarchy process (AHP). Analyses were carried out with 10 afforestation criteria and five tree species. According to the analysis, the top three ranked criteria are Economic Efficiency &gt; Carbon Stock and Credit &gt; Reducing Afforestation Cost. The five species’ priority ranking is Robinia pseudoacacia L. (0.456) &gt; Alnus glutinosa subsp. glutinosa (0.248) &gt; Populus nigra subsp. nigra (0.146) &gt; Salix alba L. (0.103) &gt; Quercus robur subs. robur (0.048). The hybrid approach is expected to increase the effectiveness of post-mining rehabilitation works.

The genome sequence of black poplar, Populus nigra subsp. betulifolia L., 1753 (Salicaceae)

We present a genome assembly from an individual Populus nigra subsp. betulifola (black poplar; Tracheophyta; Malpighiales; Salicaceae). The genome sequence is 413.2 megabases in span. Most of the assembly (99.73%) is scaffolded into 19 chromosomal pseudomolecules. Mitochondrial and plastid genomes were also assembled. Three mitochondrial assemblies have lengths of 281.85, 335.57 and 186.15 kilobases, and the plastid genome has a length of 156.37 kilobases.