Eucalyptus Camaldulensis Research Articles

Abstract Background Vector control strategies have predominantly relied on the use of synthetic chemicals, leading to the widespread of resistance among malaria vector populations. This growing resistance has prompted increased interest in alternative control methods, particularly those based on plant-derived essential oils (EOs). The present study investigates the insecticidal efficacy of five essential oils against field populations of Anopheles gambiae sensu lato from Burkina Faso. The objective was also to assess the current distribution and frequency of resistance-conferring mutations within these mosquito populations. Methods Essential oils were extracted from Cymbopogon citratus , Cymbopogon nardus , Eucalyptus camaldulensis , Lippia multiflora , and Ocimum americanum plants by hydrodistillation, and their chemical composition was analyzed by gas chromatography coupled with mass spectrometry (GC–MS). The insecticidal activity of the EOs was evaluated on Anopheles gambiae complex populations collected from fifteen localities, following the WHO tube bioassay protocol. Species identification in Anopheles complex was carried out by PCR. Molecular assays targeting specific resistance genes, particularly the knockdown resistance ( kdr ) L1014F mutation, were conducted using allele-specific PCR. The KD effect and mortality rates induced by each EO were recorded. Results GC–MS analysis revealed among the 5 EOs samples tested, monoterpenes were the dominant compounds. The KD effects of Cymbopogon citratus , Cymbopogon nardus and Lippia multiflora were more pronounced in all the study areas. The comparative analysis of knockdown times at 50% and 95% (KDT50 and KDT95) highlights significant differences in efficacy between the tested essential oils and permethrin. Overall, the essential oils exhibited significantly lower KDT values than permethrin, indicating a faster and potentially more effective action against Anopheles gambiae populations. Moreover, L. multiflora induced a rate of mortality of 100% in mosquitoes from fifteen localities. Statistical analysis revealed significant differences in mortality rates among the EOs tested. The potent insecticidal activity observed is likely due to the major terpenoid compounds present in these EOs. Among the mosquito populations analyzed, Anopheles arabiensis was predominant and exhibited high phenotypic resistance to pyrethroids in multiple locations. Conclusion The EOs of Cymbopogon citratus , Cymbopogon nardus , and Lippia multiflora could be used as alternatives where pyrethroid resistance in malaria vectors has been established. These findings support the potential integration of these plant-derived oils into environmentally sustainable vector management strategies in Burkina Faso.

Glycaspis brimblecombei Moore is an invasive insect pest that primarily targets Eucalyptus species, with a particular preference for Eucalyptus camaldulensis. The mechanism of host selection involves the recognition of host volatiles by odorant binding proteins (OBPs), which play crucial roles in various insect behaviors, including intersexual communication, oviposition, and interactions with host plants. The objective of this study was to identify the phytochemicals responsible for this host preference. The chemical composition of the essential oil extracted from the infested leaves of E. camaldulensis Dehnh. was analyzed using gas chromatography-mass spectrometry, revealing a total of 66 compounds that accounted for approximately 97.218% of the total oil. The major components identified were p-Cymene (29.78%), β-Phellandrene (15.55%), and Crypton (9.34%). Among the 66 volatiles detected, nine compounds, including Farnesol, Nirolidol, (Z,Z)-Farnesal, (Z,E)-Farnesal, Valerenol, β-Cubebene, cis-Linaloloxide, trans-Linalool oxide, and L-Linalool, exhibited the lowest Gibbs free energy (ΔG) values, ranging from -7.74 to -6.84kcal/mol and favorable interactions with the hydrophobic cavity of the OBP CcapOBP22. Molecular dynamics simulations indicated that the docked models with (Z,E)-Farnesal, cis-Linaloloxide, and β-Cubebene were flexible and stable. This study may inform future pest management strategies targeting G. brimblecombei.

Floodplain forests in the Queensland Murray–Darling Basin (QMDB) have experienced significant recruitment challenges following multiple droughts, including the Millennium Drought (1997–2009). This study investigated the impact of the rare triple-dip La Niña event (2020–2022) on floodplain tree recruitment patterns for river red gum (Eucalyptus camaldulensis Dehnh.) and coolibah (Eucalyptus coolabah Blakely & Jacobs). Field assessments across QMDB’s three water catchment areas showed recruitment at 34% of plots. Days since last flood (P = 0.04) was significantly associated with recruitment density, whereas bankfull exceedance floods showed a marginally positive effect on recruitment density (P = 0.080), and total days of exceedance had a marginally negative influence on recruitment density (P = 0.06). Open woodland and woodland areas with low canopy cover exhibited significantly higher recruitment rates (P = 0.001 and P = 0.021) compared to forests. Low native fauna grazing pressure showed strong association with increased recruitment (P = 0.007); during wet conditions, abundant grass cover diverted browsing pressure on seedlings. Demographic analysis demonstrated improved reverse J-curve distributions for both species compared with previous assessments, suggesting that this triple-dip event recruitment episode may help restore juvenile cohorts. Findings suggest that although flooding appears to contribute to recruitment through site preparation and seed dispersal, sustained rainfall appears crucial for seedling survival. These results have important implications for environmental water management, highlighting that infrequent but significant recruitment episodes may be sufficient for maintaining sustainable populations over the extended lifespans of these species, while demonstrating the limits of direct management interventions.

Native plantations foster phylogenetic cohesion while nonnative plantations promote higher species turnover in understory vegetation in subtropical managed forest.

Medicinal herbs are used to treat numerous diseases all over the world. This study investigates the enzyme inhibitory potential, antioxidant properties, and phytochemical composition of methanolic extracts from Cinnamomum verum, Nerium oleander, Laurus nobilis, and Eucalyptus camaldulensis leaves. These plants, known for their healing properties, were tested to determine how effectively they inhibit α-amylase and α-glucosidase. These essential enzymes help break down carbohydrates, and their antioxidant capacities were evaluated using DPPH and ABTS assays. Phytochemical profiling revealed significant levels of phenolics (26.44–63.56 mg GAE/g), flavonoids (6.09–37.56 mg QE/g), and tannins (12.98–34.80 mg TAE/g), with E. camaldulensis and L. nobilis exhibiting the highest phenolic content. Methanolic extracts of L. nobilis and N. oleander demonstrated the strongest inhibition of α-amylase (0.586 ± 0.015 and 0.564 ± 0.0001 mmol acarbose/g) and α-glucosidase (7.570 ± 0.107 and 8.242 ± 0.113 mmol acarbose/g), outperforming synthetic controls. Antioxidant activity correlated with phenolic content, with E. camaldulensis showing the lowest IC50 in DPPH (8.83 µg/mL) and L. nobilis in ABTS (30.32 µg/mL). These findings highlight the therapeutic promise of these plants as natural sources of enzyme inhibitors and antioxidants, supporting their use in oxidative stress-related disorders. The study underscores the significance of plant-derived bioactive compounds in developing safer, cost-effective pharmaceuticals and functional foods.

Final conditioning of 25mm thick dried E. camaldulensis lumber was carried out in small capacity batch drying kiln in laboratory, and the elastic (EL) strain and mechano-sorptive (MS) strain was analyzed by slicing method. Mean moisture content(MC) of boards increases 2.5-3.0%, while surface MC increases from 9.8% to 14.2% and center MC always keeps at 12.3% or so. Difference of each slice oven-dried length, through the thickness of the board decreases with the going on of conditioning. Compressive EL strain in the surface decreases significantly during the first 9h of conditioning, and tensile EL strain in the center doesn’t change significantly with the going on of conditioning. Compressive EL strain of sub-surface is greater than that of surface during middle and final period of conditioning, so reverse stress gradient is formed. Casehardened surface is softened by moisture picking-up and then complementary shrinkage makes EL strain and MS strain decrease, but because of the effect of drying history, the change of MS strain lags behind that of MC.

Two new acylated chromone glucosides eucamalduside D (1) and eucamalduside E (2) together with twelve known compounds were isolated from the leaves of Eucalyptus camaldulensis var. obtusa. The structures of new compounds 1 and 2 were established through 1D and 2D NMR, and HRESI-MS and their stereochemistry was established by measuring optical rotation of methyl esters and sugars obtained by methanolysis and hydrolysis respectively. Ursolic acid lactone (5) showed good immunosuppressant activity in luminol-based chemiluminescence assay performed on whole blood, neutrophils and macrophages with IC50 values of 1.74 ± 0.4, 3.1 ± 0.2 and 6.53 ± 1.59 µg/mL, respectively, while cypellocarpin Ca (13) exhibited moderate decrease in T-lymphocyte proliferation with IC50 of 6.2 ± 0.8 µg/mL.

Tree height varies across environments, with taller individuals found in cool, moist habitats and shorter trees in drier regions. Within species, trees can exhibit height variation due to environmental factors such as drought-induced dieback. A key question is what drives changes in leaf structure with increasing height-whether some trait values cannot be produced under the developmental conditions at treetops or whether differences arise because natural selection favors particular trait values at different canopy positions. Some hypotheses suggest that increasing height imposes "limits" on mature leaf traits, making some structural changes developmentally inevitable. However, selection could also favor structural changes within wide fields of developmentally possible trait configurations. We examined leaf epidermal cell size distributions in Bursera simaruba and Eucalyptus camaldulensis from seedlings to maximum tree heights in situations in which seedlings to adults were all exposed to full sun and thus had all "sun" leaves. We found that in general cell sizes increased, variance remained high, and distributions did not systematically shift with height. These results indicate that, rather than reflecting a developmental inability to produce certain leaf epidermal cell sizes at greater heights, the patterns we observed are better explained by selection simply favoring some cell sizes from among the many that development can produce.

Agroforestry, the deliberate integration of trees with agricultural crops, represents a sustainable land-use strategy that strengthens rural livelihoods and ecological resilience. By expanding tree cover and meeting rising timber and fuelwood needs, it provides both economic and environmental benefits. Diversifying farm income, improving ecosystem services, and enhancing climate adaptability further highlight its value. This study investigates the current status of agroforestry and its socioeconomic effects on farmers in Sub-Division Darazinda, District Dera Ismail Khan, Khyber Pakhtunkhwa, Pakistan. Results indicate that about 20-30 % of local farmers engage in agroforestry—primarily through Agri-Silviculture and boundary planting—motivated by financial returns and environmental considerations. Predominant species such as Eucalyptus camaldulensis (roughly 40-60 % of trees) and Dalbergia sissoo (5-15 %) generate annual earnings of Rs. 60,000-100000 per hectare. Additional income, estimated at Rs. 5,000-15,000 per hectare, is derived from non-timber products such as fodder from Acacia nilotica. Overall, agroforestry in Darazinda emerges as a practical pathway to sustainable development, advancing both livelihood security and climate goals. Nevertheless, its wider adoption is hindered by policy shortcomings, market constraints, technical limitations, and socioeconomic challenges.

The invasive tomato leafminer Tuta absoluta has recently caused heavy losses to tomato growing areas around the world including Pakistan. Considering its significant damage potential, it is essential to conduct experiments using locally available botanicals and synthetic insecticides. Therefore, studies were conducted at a farmer’s field in the district Shaheed Benazir Abad, Sindh, Pakistan during complete tomato season of 2023-24. Synthetic insecticides, i.e., Tracer 450SC ® (Spinosad 480 g/L), Belt 480 SC ® (Flubendiamide 480 g/L), Novastar 56EC ® (Bifenthrin 5%+ Abamectin 0.6%), Talstar 10EC ® (Bifenthrin), and Trigard 750 g/kg ® (Cyromazine) and botanical insecticides, i.e., Neem (Azadirachta indica A. Juss.), Tobacco (Nicotiana tabacum L.), Datura, (Datura stramonium L.), Peppermint (Mentha piperita L.), and Eucalyptus (Eucalyptus camaldulensis Dehn.), along with untreated control were evaluated against T. absoluta During both sprays, synthetic insecticides were found to be comparatively more effective than botanicals, with Flubendiamide and Spinosad being the two most effective insecticides. The effectiveness of all insecticides was comparatively better in the second spray than first spray. After one week of the two sprays, the maximum infestation reduction on tomato leaves and fruits was recorded with Flubendiamide (73.34% and 85.60%, respectively), followed by Spinosad (70.58% and 83.57%, respectively), whereas Eucalyptus and Datura were the least effective insecticides. Among botanicals, Neem resulted in a maximum corrected reduction in T. absoluta infestation on tomato leaves (52.33%) and fruits (55.20%). Due to the effectiveness of insecticides in reducing T. absoluta infestation, a significant effect on tomato fruit yield was also observed as maximum yield was recorded with Flubendiamide (433.40 ± 5.46 maunds per acre) and Spinosad (420.80 ± 3.20 maunds per acre) treatments, whereas neem (389.60 ± 4.86 maunds per acre) gave maximum yield among botanicals. Therefore, it is recommended that due to the better performance of Flubendiamide and Spinosad, they should be included in the integrated management of T. absoluta infestation in tomatoes, whereas Neem can also be used as botanical insecticide due to its effectiveness against it.

Abstract Eucalyptus (Eucalyptus camaldulensis Dehnh.) is an important exotic species in northern Nigeria commonly used for poles and timber. Sustainable management of this resource would require quantifying its volume. Stem taper equations are one of the main and most efficient methods for estimating stem volume to any merchantable limit of a species. There is currently no taper equation for Eucalyptus species in Nigeria. Therefore, this study developed taper equations for E. camaldulensis in northern Nigeria. Data for this study were obtained from a private plantation in Jalingo Local Government Area, Taraba State, Nigeria. 68 trees were felled and sectioned into 1-m bolt across the stem to a merchantable limit of 5 cm, which were used as the fitting dataset. An additional 22 trees were felled and used to validate the taper equations for stem volume estimation. Seven taper equations were initially fitted to the dataset using nonlinear least squares. The best taper equation was then refitted using a nonlinear mixed-effects approach and calibrated using diameters of one to five sections from the butt end. The taper equations were numerically integrated to obtain the stem volume, which was compared with empirical volume equations. The result shows that the Kozak (Can J For Res 27(5): 619–629. 10.1139/x97-011, 1997) equation, which included eight parameters, provided the best fit for predicting section diameters for under and over bark. The mixed-effects taper equation (NLME-TE) explained most stem diameter variations in the fitting dataset (pseudo-R 2: 0.986–0.987; RMSE: 0.547–0.578 cm) without substantial residual trends. The validation showed that the prediction accuracy of the integrated NLME-TE improved as the number of sectional diameter measurements increased, with at least a 35% reduction in volume estimate error. For practical implementation, two calibration sectional diameter measurements taken from the butt end per tree are recommended. This approach would reduce measurement effort and cost while improving model performance.

Threshold depth for girdling-induced mortality in Eucalyptus camaldulensis: a predictive approach for invasive species management.

This study was conducted in 2021 in the Department of Plant Protection, Faculty of Agriculture, University of Damascus, and in the fields of Qatana region. Alcoholic and aqueous extracts of tobacco, Nicotiana tabacum L., eucalyptus, Eucalyptus camaldulensis D., chinaberry, Melia azedarach L. and aerial parts of amaranth, Tagetes patula L. were evaluated for the control of cochineal scale insect, Dactylopius opuntiae Cockerell (Hemiptera, Dactylopiidae) and compared with chemical insecticides: chlorpyrifos, dimethoate, and lambda-cyhalothrin, and Sycro (mineral oil). The results obtained showed that the aqueous extracts of the tested plants at concentrations of 2.5 and 5.0% had moderate to low effect against the different stages of the cochineal scale insect, D. opuntiae. Whereas alcoholic extracts at a concentration of 5.0% were highly effective against males and nymphs of the insect, and the effectiveness increased with time after treatment. The average effectiveness rate for the leaves extract of tobacco, chinaberry, amaranth, and eucalyptus plants reached 51.18, 46.25, 39.65 and 32.50% for males; 38.25, 27.15, 25.21 and 20.32% for nymphs, 5 days after spraying, respectively. Whereas the effectiveness of alcoholic extracts was moderate on female insects. On the other hand, both dimethoate and chlorpyrifos pesticides had the highest effectiveness on males, nymphs, and females of the cochineal scale insect, with significant difference with the rest of the treatments. Whereas the pesticide Lambda-cyhalothrin and mineral oil had a medium effect on the instars of the insect. The results also showed that the effectiveness rate gradually increased with increasing concentration and exposure period. Accordingly, alcoholic extracts of tobacco and astragalus can be recommended for the control of the cochineal scale insect as natural and safe pesticides. Keywords: Insecticides, Dactylopius opuntiae, plant extracts, chinaberry, tobacco.

Remediation of heavy metal pollution is essential for safeguarding ecological integrity and public health. The present work aimed to prepare a novel biochar from Eucalyptus Camaldulensis leaves (EC-biochar) for the effective removal of Cd2+ and Pb2+ cations, as representative heavy metals, from aqueous solutions. The adsorption performance of Cd2+ and Pb2+ cations by EC-biochar was assessed by varying different operating parameters (e.g. pH, temperature, EC-biochar dose, adsorption time, and adsorbate concentration). The maximum removal efficiencies of Pb2+ (83.8%) and Cd2+ (89.6%) ions were achieved at pH 4.5. The pseudo-second order and Langmuir isotherm models satisfactorily predict the adsorption of Pb2+ and Cd2+ cations onto EC-biochar. The negative values of ΔG° and ΔH° demonstrated that the adsorption process is spontaneously feasible and exothermic. It is also worth pointing out that the regeneration/reuse study revealed that the as-prepared EC-biochar maintained an excellent adsorption performance after five reuse cycles, demonstrating its suitable reusability. These findings demonstrate that the EC-biochar can serve as an inexpensive, effective and recyclable adsorbent for treating heavy metal-laden effluents.

This study evaluated dosage limits of Eucalyptus camaldulensis, Hibiscus sabdariffa and Morinda lucida leaf, stem and root aqueous extracts on haematological parameters of 140 albino rats grouped into ten of five replications in a completely randomized design. Aqueous extract of 75 g, 100 g, and 125 g of three parts of the three plants were prepared separately by boiling with 1 L of water for 1 h. 1 mg/kg of the extracts was administered on the rats once daily for 30 days. Distilled water served as control. Weights of the rats were estimated while heamatological parameters were determined using ELISA kits. Pack cell volume (45.33%), mean cell haemoglobin concentration (34.11 g/dL) and mean cell haemoglobin (19.00 Pg) were higher in rats dosed 125 g/L H. sabdariffa leaf extract. Similar significant increase was observed in haemoglobin (16.12 g/dL) and red blood cell (8.97 × 1012/L) of the rats dosed 125 g/L H. sabdariffa stem extract, as well as white blood cell (30.23 × 109/L) in rats dosed with M. lucida stem aqueous extract.100 g/L of H. sabdariffa extracts improved weights and haeamatology of the rats, hence, the dosage is recommended.

Afforestation with River red gum (Eucalyptus camaldulensis) drives biotic homogenization in coastal sand dunes

Physical and morphological characterization of eucalyptus wood (Eucalyptus camaldulensis Dehnh.) from seaside windbreaks belts in Central Italy

Eucalyptus species are valuable for timber, pulp, and essential oil production. A laboratory study was conducted which shows the percentage frequency of the fungal isolates in Modibbo Adama University and was calculated based on the total number of isolates obtained from the four different locations. The results showed varying levels of abundance for the four identified fungal species: Rhizopus nigricans was isolated in 2 out of 14 samples, resulting in a percentage frequency of 14.2%. Aspergillus flavus had the second-highest occurrence, being isolated in 5 out of 14 samples, with a percentage frequency of 35%. Penicillium notatum was the least frequent, isolated in just 1 out of 14 samples, giving a percentage frequency of 7.1%. Aspergillus brasiliensis was the most abundant species, isolated in 6 out of 14 samples, accounting for 42.8% of the total isolates. The results of this study highlight the prevalence of fungal pathogens associated with Eucalyptus camaldulensis in the Modibbo Adama University area. Aspergillus brasiliensis and Aspergillus flavus were the most commonly found fungi, indicating that these species may play a significant role in the degradation of Eucalyptus leaves and other tissues. Rhizopus nigicans and Penicillium notatum were less frequent but still present, suggesting their contribution to the overall fungal biodiversity within the study area. This research demonstrates the need for further investigation into the pathogenicity of these fungi, their potential impact on Eucalyptus trees, and the development of management strategies to mitigate fungal infections.

Quantification of tree biomass in the tropics is a time-consuming activity, especially the measurement of certain biomass components, such as the tree height, diameter at various part of the tree stem. This study assessed the Quantification of aboveground biomass and carbon sequestration potentials of Eucalyptus cameldulensis specie at Dayi Plantation, Katsina State, Nigeria. The plantation was stratified into three different age series (1989, 1990 and 1991). In each stratum, a non-destructive approach was adopted and (5) sample plots of 50 x 50m were laid across each of the three (3) age series. All standing trees were marked, numbered and their attribute such as diameter at breast height (DBH), diameter at three different position (bottom, middle and top) and height (HT) were measured and recorded. A constant value of wood density (0.58) was obtained from the web. A total number of 1,349 tree stands were recorded for the entire plantation and the total quantity of 25,295 kg/ha AGB was estimated for the plantation, the estimated carbon stock is 12,647.5 kg/ha and the sequestered carbon, which represents the amount of carbon dioxide absorbed and stored by the ecosystem over time is 46,374.17 kg/ha. Conclusively, it is believed that the result of this study serve as input to forest managers, researchers and policy makers in planning and management of Eucalyptus camaldulensis in the state or region with similar environmental conditions.

Influence of Eucalyptus camaldulensis Dehnh on the growth, productivity and physiology of three associated crops in the Sudano-Sahelian zone of Burkina Faso, West Africa