Search Results (827)

In 2019, bacterial canker caused by Pseudomonas syringae pv. actinidiae was first identified in Actinidia arguta. This disease has led to significant yield reduction, plant mortality, and substantial economic losses in A. arguta cultivation. Its emergence poses a novel challenge to the sustainable global production of kiwifruit. Currently available treatments for bacterial canker caused by P. syringae pv. actinidiae are scarce. Moreover, the environmental toxicity of copper-based compounds and emerging antibiotic resistance issues necessitate the development of eco-friendly control strategies. Disease management strategies based on biocontrol bacteria have shown broad application prospects. In this study, the isolate CHHM-1 with significant antagonistic activity against P. syringae pv. actinidiae was isolated from the rhizosphere soil of healthy A. arguta. It was identified as Pseudomonas koreensis through 16S rRNA gene and whole-genome sequencing. Genomic analysis revealed that the isolate CHHM-1 harbors various genes related to biocontrol, plant growth promotion, and antibiotic resistance, suggesting strong environmental adaptability and functional potential. Furthermore, the strain exhibited multiple plant growth-promoting traits, such as nitrogen fixation, phosphate solubilization, siderophore production, and synthesis of indole-3-acetic acid (IAA). In vitro antagonism assays confirmed the strong antagonistic activity of the isolate CHHM-1 against P. syringae pv. actinidiae. A dual-culture plate assay showed an average inhibition zone of 4.36 cm, while preventive application on plants significantly reduced lesion length to 1.3 mm (vs. 6.2 mm control) in shoots and lesion area to 10% (vs. 80% control) in leaf discs. Further antibacterial tests revealed that its inhibitory mechanism is attributed to secreted antimicrobial substances. These findings provide a promising candidate for developing novel biopesticides to combat P. syringae pv. actinidiae variants, reduce chemical dependency, and foster sustainable A. arguta production. Full article

Plant growth-promoting bacteria (PGPB) have a wide range of applications in agriculture and environmental management. They act as biostimulants and biofertilizers to enhance crop quality and yields in a more sustainable way. The present research aimed at isolating three active strains from the arid rhizosphere soil to act as biofertilizer. The plant growth-promoting features were evaluated in vitro and their implementation on pepper growth and yield were assessed and measured. Regarding IAA and ammonia production, the three designated isolates (P21, P22-1 and P58) showed patterns of high IAA production, producing 154.47 µg/mL, 155.03 µg/mL, and 188.65 µg/mL, respectively. Furthermore, considerable amounts of ammonia were detected in the supernatant of peptone water medium after 72 h of growth. Isolate P21 produced the maximum amount and generated 17.38 μmol/mL, whereas both P22-1 and P58 displayed lower amounts (15.47 and 15.92, respectively), without significant differences. P-solubilization efficacy calculated 18.7% (isolate P21), 64% (isolate P22-2), and 54% (isolate P58) when compared with un-inoculated medium. The molecular identification by 16S rRNA displayed that the three isolates belonged to Pseudomonas alkylphenolica strain P21 (PX257452), Pantoea agglomerans strain P22-1 (PX257453), and Pantoea brenneri strain P58 (PX257454). Applying the selected strains with sweet pepper in the presence of rock phosphate (RP) was assessed under greenhouse conditions. Three treatments (adding bacterial suspension at 0, 10 and 20 days after transplanting) from P21, P22-1, and P58 strains revealed that P21(3), P21(2), P22-1(3), and P58(3) treatments are considered the most promising treatments related to plant height, root length, leaf area, number of leaves per plant, leaf P-uptake, and stem P-uptake in addition to total plant P-uptake. In addition, the PCA biplot showed that MSP (mono-super phosphate), P22-1(3), and P58(3) are closely associated with high phosphorus uptake, indicating their effectiveness in enhancing phosphorus absorption by solubilizing insoluble forms. Eventually, PGPB will help the environment by improving soil fertility and structure, decreasing the need for toxic chemical fertilizers, and improving ecosystem health overall. Full article

Mercury, a global pollutant with both persistence and high toxicity, has remained a focal point in environmental science research over the past half-century. As a key pathway in the terrestrial mercury cycle, plants actively assimilate gaseous elemental mercury (Hg⁰) through leaf stomata, constituting a critical pathway for terrestrial mercury cycling. The litterfall mercury concentration serves as a biological indicator to quantify vegetation’s mercury interception capacity, providing essential data for global mercury cycle modelling. To investigate this, 15 sampling sites throughout the country were selected, and litterfall was collected monthly for 12 consecutive months to determine the litterfall amount, composition, and leaf mercury dynamics. The results revealed that annual litterfall production ranged from 1.10–8.56 t·hm⁻², with leaf components dominating (45.58%–89.11%). Furthermore, three seasonal litterfall patterns emerged: unimodal, bimodal, and irregular. Regarding mercury, the mercury concentration in leaf litter exhibited a certain seasonal variation trend, with the mercury content in leaves in most areas being higher in autumn and winter. Specifically, the mercury concentration in litterfall showed a significant negative correlation with latitude and a significant positive correlation with air temperature, precipitation, and litterfall amount (p < 0.05). Additionally, the concentration of Hg in dying leaves exhibited some geographical variations. Full article

To provide a scientific basis for pest control, this study evaluated the insecticidal activity of novaluron against the fall armyworm (Spodoptera frugiperda) and diamondback moth (Plutella xylostella). The leaf-dip method determined the toxicity of novaluron to second-instar larvae, while corn leaves and cabbage treated with sublethal (LC₁₀) and median lethal concentrations (LC₅₀) of novaluron were used to feed the larvae. Enzyme-linked immunosorbent assays (ELISA) measured the activities of detoxifying enzymes [carboxylesterase (CarE), cytochrome P450 (P450), glutathione S-transferase (GST), and acetylcholinesterase (AChE)] and ecdysteroid (Ecd) levels in the pests after 24 and 48 h of treatment. Results indicated that after 24 h, AChE was involved in diamondback moth metabolism and CarE activity was inhibited. After 48 h, P450 and GST participated in fall armyworm detoxification, whereas P450 and GST were active in diamondback moth detoxification, with other enzyme activities normalizing. Novaluron also altered Ecd levels in both pests. These results demonstrate differing detoxification mechanisms in fall armyworm and diamondback moth, likely due to their unique physiological and ecological traits, and support the potential use of novaluron in pest management strategies. Full article

The overuse of pesticides has raised serious food-safety and environmental concerns. Carbon dots (CDs) can act as biostimulants by enhancing photosynthesis, thereby promoting plant growth and stress tolerance. However, their roles in plant pesticide detoxification remain unclear. This study synthesized nitrogen-doped carbon dots (N-CDs) with strong blue fluorescence, excellent biocompatibility, and no cytotoxicity observed in HEK 293T cells. The N-CDs were synthesized from 1.025 g citric acid and 0.379 g urea, producing particles with a size of around 2.42 nm and abundant hydrophilic groups. When applied to tomato plants, N-CDs (especially at 150 mg·L⁻¹) significantly reduced chlorothalonil (CHT) residues affecting tomato, by up to 66%. Importantly, N-CDs also improved tomato plant growth, reversing the negative effects of CHT on key parameters such as height, leaf area, and biomass. Indeed, under CHT conditions, N-CDs significantly reduced the contents of malondialdehyde, superoxide, and hydrogen peroxide. In contrast, N-CDs significantly increased the activities of superoxide dismutase, peroxidases, catalase, and ascorbate peroxidase to 117.57%, 158.53%, 162.79%, and 152.23%, respectively. Notably, N-CDs dramatically changed the glutathione pool for tomato detoxification. Overall, this study synthesized the non-cytotoxic N-CDs that not only promote tomato growth but also alleviate CHT toxicity by strengthening the tomato’s antioxidant defense system. Full article

This study explores the anticancer, antioxidant, and phytochemical activities of Laurus nobilis L. ethanolic leaf extract. The extract demonstrated selective cytotoxicity against four human cancer cell lines, showing strong cytotoxic effect against ovarian (ES2), head and neck (SAS), and colorectal (HT-29) cancer cells, with IC₅₀ values ranging from 3.8 ± 0.3 to 4.4 ± 0.6 µg/mL. Notably, it exhibited only moderate inhibition of the MDA-MB-231 breast cancer cell line (IC₅₀ = 18.5 ± 0.8 µg/mL), possibly reflecting intrinsic differences in cell line sensitivity. Importantly, the extract showed low toxicity toward normal human fibroblasts (HDF), with an IC₅₀ value exceeding 100 µg/mL, indicating a favorable selectivity profile. The flow cytometry analysis showed that the extract caused cell death and stopped the cell cycle in both SAS and ES2 cancer cell lines. In SAS cells, extract treatment significantly increased apoptotic cells (21.1% ± 0.3%) compared to the control (6.3% ± 0.4%), along with G2 phase accumulation, indicating G2 arrest. Similarly, in ES2 cells, apoptosis increased (16.2% ± 1.3% vs. control 8.1% ± 1.0%), and a significant cell accumulation in the S phase was observed, suggesting disruption of cell cycle progression. Antioxidant screenings showed impressive dose-dependent DPPH radical scavenging activity (25–2000 µg/mL), although less potent than ascorbic acid (2.6 µg/mL). UPLC-QTOF/MS phytochemical analysis revealed various phenolic constituents, such as flavonoids and phenolic acids, and an inferred association with the recorded bioactivities. This preliminary work indicates that L. nobilis extracts may act as natural anticancer and antioxidant agents; however, it was limited to in vitro testing with non-standardized samples, underscoring the need for further research to validate and extend these findings for future applications. Full article

Terrestrial cross-boundary inputs of leaf litter serve as a critical foundation for secondary productivity in freshwater ecosystems. The regulatory mechanisms of tannins in leaf litter on degradation rates under submerged conditions remain unclear. This study employed leaf litter from low-tannin plants Osmanthus fragrans (A) and Canna glauca (B) as decomposition substrates, with the high-tannin species Myriophyllum verticillatum (C) incorporated to adjust tannin levels. A 140-day hydroponic degradation experiment was conducted under controlled temperature and dark conditions, which included four mixed litter treatments with a gradient of tannin additions (AB as the control, 0 g; ABC1: 0.5 g; ABC2: 2.5 g; ABC3: 4.5 g) along with two single-species treatments (A and B). The following results were found: (1) Low tannin levels (ABC1) promoted degradation rates of A and B (increased by 1.33–12.70%), whereas high tannin (ABC3) inhibited decomposition (decreased by 6.21–6.82%). (2) Tannin–protein complexes reduce nitrogen bioavailability and inhibit nitrification, thereby disrupting the nitrogen cycle in aquatic systems. In ABC3, total nitrogen content in A and B litter increased by 17.69–26.46% compared to AB, with concurrent 59.29% elevation in water NH₄⁺-N concentration. (3) High tannin induced dominance of oligotrophic stress-resistant bacterial communities (e.g., Treponema) through nutrient limitation and toxicity stress; however, their low metabolic efficiency reduced overall decomposition efficiency. Research reveals that the ecological benefits of plant secondary metabolites outweigh their nutritional quality attributes. Full article

In order to develop a new environmentally friendly microbial herbicide for the field of weed control, this study used the metabolite butyl hydroxybenzoate (BP) of the HY-02 strain of Alternaria as the research object. The BP emulsion formula was determined to be a mixture of BP, methanol, and Tween-20 in a ratio of 1:1:2 g/mL. The seed germination inhibition effect, the phytotoxicity of living plants, crop safety, and the field effect of the emulsion were studied. Research has found that adding 0.75% BP emulsion to the seed culture medium inhibits the germination of weed seeds such as Amaranthus retroflexus L., Malva verticillata L. var., and Chenopodium album L. While Brassica campestris L. seeds were unaffected, Triticum aestivum L and Hordeum vulgare L. stem and leaf growth were inhibited. Cucumis sativus L., Lactuca sativa L. var. asparagina, Spinacia oleracea L., and Capsicum annuum L. seeds are significantly inhibited, with germination rates below 20%. We sprayed 0.75% BP emulsion onto live potted plants; among the weeds, the incidence of Amaranthus retroflexus L., Lepyrodiclis holosteoides, Thlaspi arvense L, Galium spurium L., Malva verticillata L. var. Crispa, Chenopodium album L., and Avena fatua L reached 100%. The Pisum sativum L. and Triticum aestivum L. crops were not affected (NS), and they had slight plant height inhibition and slight susceptibility (LS) to highland Hordeum vulgare L. and peppers. They were highly phytotoxicity to Cucumis sativus L. and Spinacia oleracea L. Some plant leaves became infected and died, with incidences of 85% and 82%, respectively. The field experiment showed that after diluting the BP emulsifiable concentrate, the seedling stage spray was inoculated into the Triticum aestivum L. field, and it was found that the BP emulsifiable concentrate at the concentration of 1.00%~0.75% had a herbicidal effect on weeds such as Chenopodium album L., Elsholtzia densa Benth, and Amaranthus retroflexus L. in the Triticum aestivum L. field, and it was safe for Triticum aestivum L. crops in the field. These results indicate that BP emulsion could be developed into a new environmentally friendly microbial herbicide for field application in grass (Triticum aestivum L. and Hordeum vulgare L.) crops. At the same time, BP’s excellent antibacterial, low-toxicity, hydrolysis, and other effects can promote diversification in herbicide development. Full article

Background/Objectives: Allophylus edulis, known as “vacum”, is popularly used in Brazil for treating inflammatory diseases, though no scientific evidence supports the anti-inflammatory activity of its leaf infusion. This study aimed to assess the chemical composition, antioxidant and anti-inflammatory properties of the lyophilized infusion (ILAE) of A. edulis leaves, as well as the pharmacological effects of its hydromethanolic fraction (HMf) and the isolated compound vitexin 2″-O-rhamnoside (AE-1). Histochemical analyses of the leaves and in silico toxicity prediction of AE-1 were also performed. Methods: Fresh leaves were used for histochemical analysis and preparation of ILAE. The infusion was fractionated into n-hexane (Hf), ethyl acetate (EAf), and HMf fractions. Total phenols, flavonoids, flavonols, tannins, and antioxidant activity were determined by spectrophotometric methods. AE-1 was obtained from HMf through chromatographic methods and was evaluated by the ProTox model in relation to toxicity predictions (in silico). Anti-inflammatory effects of ILAE (3, 30, 100 mg/kg), HMf (3, 30 mg/kg), and AE-1 (3 mg/kg) were evaluated in carrageenan-induced paw edema, pleurisy, and CFA-induced inflammation in mice. Results: ILAE and its fractions were rich in total phenols (≤177 mg GAE/g) and showed potent antioxidant activity. Histochemical analysis revealed leaf secretory structures. AE-1 showed no hepatotoxic, carcinogenic, mutagenic, or cytotoxic effects in silico. All doses of ILAE and HMf reduced edema, hyperalgesia, and leukocyte migration. ILAE (30 mg/kg), HMf (30 mg/kg), and AE-1 (3 mg/kg) reduced CFA-induced inflammatory responses. Conclusions: ILAE contains polyphenolic compounds with antioxidant, anti-inflammatory, and antihyperalgesic properties, supporting the traditional use of A. edulis and its potential in inflammation-related therapies. Full article

Heavy metal pollutants and organic contaminants often co-exist in the environment, posing significant ecological risks due to their combined toxicity. Phytoremediation, a plant-based biotechnology, offers a promising solution for pollutant removal. This study investigated the potential cadmium (Cd) removal capacity of Narrow Crown Black-Cathay poplar (Populus × canadensis Moench × Populus simonii Carr. f. fastigiata Schneid.) under combined Cd-phenol stress. The results showed that the combined stress synergistically inhibited the photosynthetic physiological characteristics, with an inhibition rate up to 54.0%, significantly higher than that under single stress (p < 0.05). Cd accumulation varied markedly among plant organs, following the order: root (ranging from 4000.2 to 9277.0 mg/kg) > stems (ranging from 96.0 to 383.6 mg/kg) > leaf (ranging from 10.3 to 40.1 mg/kg). Phenol enhanced Cd absorption and enrichment in the roots by up to 1.8 times but reduced its translocation to aboveground parts by 37.8–40.0%. Notably, at low Cd concentrations, the Cd removal efficiency under combined stress (26.0%) was substantially higher than under single Cd stress (6.6%). In contrast, biomass, tolerance index, and root–shoot ratio were slightly affected in all treatments (p > 0.05). These findings demonstrate that Narrow Crown Black-Cathay poplar is a suitable candidate for the short-term remediation of Cd in environments co-contaminated with cadmium and phenol. Full article

Alkanna tinctoria (L.) Tausch is a valuable medicinal plant known for its root-derived hydroxynaphthoquinone enantiomers, alkannin/shikonin (A/S), which exhibit significant pharmaceutical and cosmeceutical potential. However, its limited natural distribution and overharvesting pose conservation challenges, necessitating sustainable cultivation and extraction strategies. The application of Natural Deep Eutectic Solvents (NaDESs) has garnered significant attention as sustainable alternatives to conventional solvents. However, their toxicity in living plant systems remains largely unexplored. This study presents the successful establishment of an ex situ hydroponic cultivation system using the nutrient film technique (NFT) to grow A. tinctoria under greenhouse conditions. The system promoted plant acclimatization, vigorous root development, and initial production of A/S derivatives. In parallel, the toxicity evaluation of a bio-based NaDES, LeG_5_20 (levulinic acid–glucose, 5:1, with 20% water), applied as a circulating medium, was assessed. Physiological stress responses of the plants to NaDES circulation were assessed through non-destructive measurements, including stomatal resistance, photosynthetic and transpiration rates, and sub-stomatal CO₂ concentration. Short-term (24 min) exposure to NaDES showed no significant adverse effects, while longer exposures (4–8 h) induced marked stress symptoms and loss of leaf area. These findings demonstrate the feasibility of integrating green hydroponic systems with eco-friendly extraction solvents and provide a framework for further optimization of plant age, solvent exposure time, and system design to enable sustainable metabolite recovery without plant destruction. Full article

The intensive use of chemical pesticides has significantly impacted the environment and human health, encouraging the search for more sustainable and environmentally safe pest management strategies. In this context, botanical pesticides emerge as a promising solution, distinguished by their natural origin and lower toxicity. Although botanical insecticides have demonstrated their potential, these solutions are still little explored in scientific and technological terms, representing an expanding field to develop safer agricultural biological pesticides. The Meliaceae family, especially the Trichilia genus, has been recognized for its richness in bioactive compounds with insecticidal potential. However, Trichilia claussenii remains little studied, despite its occurrence in Brazilian ecosystems. Therefore, this article aims to analyze the information on the botanical and phytochemical characteristics and bioinsecticidal activity of T. claussenii, aiming to highlight its potential as a natural resource for biological pest control. The leaf and fruit extracts of T. claussenii revealed the presence of bioactive metabolites. The group of terpenes is highlighted, notable for their role in the chemical defense of plants and for their recognized insecticidal activity. In the leaf extract, terpenes were the most abundant class, representing 46.3% of the total identified. In the fruit extract, terpenes were also prominent, although to a lesser extent (34.5%). Additionally, a phytochemical screening of the aqueous leaf extract indicated the presence of coumarins, flavonoids, and alkaloids, compounds commonly associated with insecticidal activity. By consolidating this knowledge, we aim to encourage new research and the development of a botanical bioinsecticide based on this species. Full article

Background/Objectives: Dipsaci Radix (Dipsacus asper) and Phlomidis Radix (Phlomoides umbrosa) are both traditional medicines used in Korea and China for various bone-associated diseases. However, the two are misused due to similarities in name and appearance. Additionally, D. japonicus root frequently contaminates Dipsaci Radix in Korean herbal markets. Methods: We examined morphological plant traits and performed a DNA barcoding analysis using ITS2 and matK sequences to differentiate between these three species. The effects of root extracts on bone resorption and osteoclast differentiation, measured as tartrate-resistant acid phosphatase (TRAP)-positive cell formation, were evaluated using mouse (5 weeks male ICR mice) bone marrow-derived macrophages. Cytotoxicity assays were conducted to assess extract safety. Results: Phlomoides umbrosa is easily distinguished by its verticillaster inflorescences and 2-labiate corollas. Dipsacus asper and D. japonicus, which share globose inflorescences, are distinguishable by flower color and leaf lobation. The ITS2 and matK sequences clearly differentiated the three species, with haplotype analysis supporting their genetic distinctiveness, enabling robust species discrimination. All three extracts decreased osteoclastic bone resorption and inhibited TRAP-positive cell formations in a dose-dependent manner. Only the D. japonicus extract demonstrated toxicity. Conclusions: This integrative study provides the current scientific names of the original species and proposes their use in the Korean Herbal Pharmacopoeia. Moreover, a reasonable molecular method for authenticating medicinal materials is suggested. Dipsacus japonicus shows promise as an additional origin species in the Korean Pharmacopoeia. However, processing methods that reduce toxicity must be discovered. Full article

Pollution from heavy metals represents one of the most important threats to crops. Among these, Nickel (Ni) represents a dangerous element, strictly related to anthropic activity and easily accumulated in plants. In this study, effects of high levels (1 mM) of Ni²⁺ were investigated in barley (Hordeum vulgare L. cv. Nure) grown hydroponically, inducing a severe reduction in plant growth, as well as genotoxic damage. Moreover, stress affects photosynthesis, inducing a decrease in Fv/Fm and ΦPSII and an increase in D1 protein and RuBisCO (RbcL) abundance to compensate for the loss of photosynthetic efficiency. Changes were observed in carbon metabolism, with increases in phosphofructokinase, glyceraldehyde-3P dehydrogenase-NAD⁺, and pyruvate kinase expression confirmed by increased proteins and activities. Notably, there was an evident rise in PEP carboxylase activity, presence, and expression. This increase boosts the TCA cycle (increased fumarase) and supports photorespiration. Evident rises were observed also for glucose-6P dehydrogenase activity and presence. Ni²⁺ stress induced an evident increase in enzymes involved in nitrogen metabolism: particularly, the chloroplastic GS2/Fd-GOGAT cycle and N assimilation through the cytosolic glutamate dehydrogenase reaction were enhanced. These results design a specific stress-responsive metabolism by diverting the synthesis of N-compounds through alternative C/N assimilation pathways to counteract the effects of Ni²⁺ toxicity. This study depicts a diversion of the main C/N metabolism network towards an increase in leaf N assimilation, using carbon skeletons from dark CO₂ fixation under high Ni²⁺ stress. These results may provide possible targets for the improvement of heavy metal tolerance in cereals. Full article

The present study is part of the efforts to develop a micropropagation protocol for Arracacia xanthorrhiza, focusing on improving in vitro establishment, reducing senescence, and balancing plant growth regulators. To control bacterial contamination during culture initiation, ampicillin and tetracycline were tested using impregnated paper disks. Ampicillin at 100 mg·L⁻¹ achieved 92.4% survival and reduced bacterial contamination to 25.2%, compared to 65.6% in the untreated control, confirming its effectiveness as a low-cost and non-toxic solution. Senescence reduction was evaluated through the addition of activated charcoal and silver nitrate (AgNO₃); the latter, at 26 µM, significantly enhanced explant survival, reduced leaf senescence, and promoted shoot and sprout formation. Three plant growth regulators—6-benzylaminopurine (BAP), kinetin (KIN), and meta-topolin (mT)—were tested at multiple concentrations. Meta-topolin at 1 µM produced 3.5 sprouts and 7.2 leaves per plant, demonstrating three times greater biological activity than BAP and optimal morphogenetic response. The integration of antimicrobial control, ethylene inhibition, and cytokinin optimization resulted in a reliable and scalable protocol for A. xanthorrhiza micropropagation. As a concluding remark, these findings provide a practical and efficient framework for clean plant production, with direct applications in conservation, breeding, and commercial propagation of this underutilized Andean crop, while highlighting the need for further validation across genotypes. Full article