Plant based natural products as potential ecofriendly and safer biopesticides: A comprehensive overview of their advantages over conventional pesticides, limitations and regulatory aspects

Artemisia annua L. essential oil-loaded chitosan nanoparticles: synthesis, characterization, in-vitro release kinetics, and acetylcholinesterase inhibition as a mode of action against plant-parasitic nematodes

This study aimed to develop Artemisia annua oil-loaded chitosan nanoparticles (AANPs) and evaluate their efficacy as bio-nematicide against M. incognita. The direct application of essential oils is limited by poor stability, volatility, and low water solubility. Nanoencapsulation improves their stability and bioavailability. AANPs were synthesized via ionic gelation, achieving 50 % Encapsulation efficiency and 25 % Loading capacity. DLS, SEM-EDX, FTIR, and XRD characterized spherical nanoparticles (90.34 nm) and successful encapsulation. TGA/DTG indicated improved thermal stability. Phytochemical analysis of AAO identified (E)-β-Farnesene (12.09 %), Germacrene D (11.68 %), and Camphor (11.66 %) as main constituents. In vitro release studies demonstrated that 67.4 % of the oil was released in acidic conditions within 48 h. AANPs inhibited egg hatching by 61.47 % and 71.56 % at 3000 μg/mL and 5000 μg/mL doses respectively. Larvicidal activity of AANPs reached 88.67 % at 5000 μg/mL, compared to 100 % mortality by commercial nematicide Nimitz. AChE inhibition assay yielded an IC₅₀ of 1.844 μg/mL for AANPs compared to Physostigmine. Molecular docking revealed Germacrene D as a key inhibitor, with a docking score of -6.8 kcal/mol. AANPs showed improved nematicidal and AChE-inhibition. This study demonstrates that nanoencapsulation enhances the stability, efficacy, and controlled release of AAO, offering a promising eco-friendly alternative for nematode management.

Interactive Effects of Temperature and Ateleia glazioviana Baill (Fabaceae) Toxicity on Aedes aegypti (Diptera: Culicidae) Mosquito Life-History Traits

Understanding the complex interplay between environmental factors and mosquito populations is crucial for effective vector-borne disease control. In this study, we investigated the combined effects of temperature and Ateleia glazioviana toxicity on the development and survival of Aedes aegypti, utilizing artificial microcosms. The first experiment used A. aegypti eggs, with microcosms varying by room temperature (18 °C and 25 °C) and exposure to A. glazioviana leaves, either without prior incubation or with a 14-day pre-incubation period. The second experimental design involved introducing larvae, with microcosms varying by room temperature (18 °C and 25 °C) and exposure to A. glazioviana leaves after a 14-day incubation period. For both experiments, we used only ultra-pure water and food for the control. Our results demonstrate that plant leachate toxicity had a more pronounced effect than temperature, with increased toxicity levels driving higher larval mortality rates. This reduction in competition among surviving larvae led to the development of larger individuals, consistent with the temperature-size rule. Notably, the impact of leachate toxicity was most significant when A. aegypti was exposed during the egg stage. Additionally, we observed that elevated temperatures were linked to increased wing asymmetry and reduced body size, suggesting heightened developmental instability under environmental stress. These findings have important implications for biological control strategies, emphasizing the need for pre-emptive measures before oviposition. Moreover, they challenge the commonly held assumption that temperature alone is the dominant factor shaping A. aegypti populations in Neotropical regions, highlighting the complex role of other ecological stressors.

CaMKK as a Potential Target for the Natural Product Insecticide Cytisine against Megoura japonica Matsumura

Cytisine, a botanical compound, has strong contact activity against a variety of aphids. However, the target and mechanism of its aphidicidal action remain unclear. In this study, the biochemical characteristics of cytisine against Megoura japonica were tested, and the potential target proteins of cytisine were identified, and further verified by fluorescence quenching and molecular docking. Cytisine can affect the activity of Ca2+, Mg2+-ATPase, and Na+, K+-ATPase, with inhibitory rates of 50.00% and 65.22%, respectively. Sixty-eight and fifty-one major binding proteins were identified by drug affinity responsive target stability (DARTS) and cellular thermal shift assay and mass spectrometry (MS-CETSA), respectively. 125 up-regulated and 68 down-regulated genes were obtained by transcriptome sequencing. By combining the candidate target genes of transcriptomics with the potential target proteins of DARTS and MS-CETSA, CaMKK and PPP2R3B were speculated as potential target proteins. The molecular docking results showed that the binding energies of cytisine to CaMKK and PPP2R3B were -6.61 kcal/mol and -6.53 kcal/mol. The fluorescence intensity of CaMKK protein decreased by 28.50, 34.86, 39.68, 51.00, 55.16, 73.99, and 83.29% after different concentrations of cytisine treatment. This research proved that CaMKK is the potential target of cytisine, providing a new target resource for the creation of new pesticides.

A Potent Plant-Derived Chitinase: Structural Informatics and Insecticidal Activity against Helicoverpa armigera

Helicoverpa armigera (cotton bollworm) is a globally distributed lepidopteran pest that causes estimated annual agricultural losses exceeding 5 billion USD. While chemical pesticides remain the primary control strategy, their prolonged use has led to significant environmental contamination, development of widespread insecticide resistance, and non-target organism toxicity. These limitations underscore the critical need for plant-derived biopesticides that offer target specificity, environmental biodegradability, and sustainable pest management solutions without promoting resistance development. Here, we elucidate the insecticidal potential of Nelumbo nucifera Chitinase (NnChi) against the insect H. armigera through structural informatics and in-vivo insecticidal bioassays. SDS-PAGE showed a single band of ~32 kDa, and LC-MS/MS analysis depicted a fragment of 10 amino acids with 100% identity with Family 19 Class I Chitinase of Mangifera indica. NnChi-predicted structure revealed its two domains (ChB D, Cat D) connected through linker region and docking analysis of both these domains with (GlcNAc)4 showing binding affinities of -5.6 kcal/mol and -7.0 kcal/mol, respectively. MD simulation (100 ns) showed that 4 residues (RQCR) of ChB D and 4 residues (NRIP) of Cat D contributed to binding with (GlcNAc)4. To the best of our knowledge, we are reporting the molecular interactions of both domains (ChB D and Cat D) with (GlcNAc)4 via simulation studies for the first time. These computational findings were further verified through insecticidal assay. Significant larval mortality of H. armigera was observed from 3rd-6th instar against 15 µg/g NnChi treatment. Among life cycle parameters, larval and pupal duration, adult eclosion, larval and pupal weight are significantly decreased in a concentration-dependent manner as compared to control. Our integrated structural-functional characterization demonstrates that NnChi exhibits significant insecticidal activity against Helicoverpa armigera. These findings establish NnChi as a promising biopesticide candidate worthy of further investigation.

Comprehensive In Vitro and In Silico Analysis of Antimicrobial and Insecticidal Properties of Essential Oil of Myrtus communis L. from Algeria

This study investigated the phytochemical composition and biological activities of Myrtus communis essential oil (EO) from Algeria, focusing on its antimicrobial, antifungal, and insecticidal properties using in vitro and in silico approaches. Gas chromatography-mass spectrometry (GC-MS) analysis identified myrtenyl acetate (57.58%), 1,8-cineole (17.82%), and α-terpineol (6.82%) as the major constituents. M. communis EO exhibited significant antibacterial activity, particularly against Staphylococcus aureus (13.00 ± 0.70 mm) and Salmonella typhimurium (13.00 ± 1.50 mm), with moderate inhibition of Bacillus subtilis (10 ± 1.00 mm) and Escherichia coli (9.00 ± 0.70 mm), while Pseudomonas aeruginosa showed resistance. The antifungal activity was notable against Fusarium oxysporum (16.50 ± 0.50 mm), Aspergillus fumigatus (11.00 ± 1.00 mm), and Penicillium sp. (9.00 ± 0.60 mm) but ineffective against Aspergillus niger. Insecticidal activity against Tribolium castaneum was evaluated using contact toxicity, fumigation toxicity, and repellent activity assays. The EO demonstrated potent insecticidal effects, with an LC50 value of 0.029 µL/insect for contact toxicity and 162.85 µL/L air for fumigation after 96 h. Additionally, the EO exhibited strong repellent activity, achieving 99.44% repellency at a concentration of 0.23 mg/cm2 after 24 h. Density functional theory (DFT) calculations provided insights into the molecular geometry and electronic properties of the key bioactive compounds. Molecular docking studies evaluated their binding affinities to bacterial enzymes (DNA gyrase, dihydrofolate reductase6, and Gyrase B) and insecticidal targets (acetylcholinesterase), revealing strong interactions, particularly for geranyl acetate and methyleugenol. These findings highlight M. communis EO as a promising natural antimicrobial and insecticidal agent, with potential applications in plant protection and biopesticide development.

Toxicity of Foeniculum vulgare essential oil, its main component and nanoformulation against Phthorimaea absoluta and the generalist predator Macrolophus pygmaeus

The encapsulation of essential oils (EOs) in nanostructured lipid carriers (NLCs) represents an innovative and advanced approach to improve their stability and efficacy. This study evaluated, for the first time, the toxicity of Foeniculum vulgare EO (FVO), its main component, and nanoformulation (FVO-NLC) on Phthorimaea absoluta and their side effects on generalist predator, Macrolophus pygmaeus. The obtained FVO-NLC had spherical and small (86.32 nm) particle sizes, and its encapsulation efficacy was greater than 98%. FTIR analysis revealed no significant chemical interaction between EO and NLC components. Trans-anethole (TAL) (66.22%) was identified as the key FVO component. The leaf dip method was used for bioassays. FVO-NLC and FVO showed a similar level of contact toxicity against P. absoluta with LC50 values of 5.57 and 5.44 µL/mL, respectively, while TAL had an LC50 value of 3.93 µL/mL. The lethality test revealed the slow and persistent release of FVO from FVO-NLC. Furthermore, the life table data were analyzed using the TWO SEX-MSChart program. Results indicated that all selected bio-insecticides at their LC50 values reduced fecundity and negatively affected biological and population growth parameters in target pest, and usage of them was proved to be harmless for the predator according to IOBC protocols.

Exploring synergistic insecticidal effects of binary mixtures of major compounds from six essential oils against Callosobruchus maculatus

The cowpea seed beetle, Callosobruchus maculatus, causes significant damage to stored grains of food legumes. Given the environmental and health hazards associated with synthetic fumigants and residual insecticides, there is an urgent need for safer alternatives. This study investigates the insecticidal potential of six different essential oils and their major components based binary mixtures activities against C. maculatus. The EOs were extracted by hydrodistillation and characterized by gas chromatography-mass spectrometry. The insecticidal activity of each EO was evaluated by fumigation in vitro. The major components of the EOs showing significant insecticidal activity (1,8-cineole, carvacrol, pulegone, and eugenol) were evaluated individually and in sublethal binary mixtures to determine synergistic effects at a 1:1 ratio. Notably, the EO of R. officinalis exhibited the highest fumigant toxicity, with an LC50 of 29.06 µl/l air in males and 44.27 µl/l air in females at 48 h. The major components were more potent than the complete EOs, particularly 1,8-cineole (males: LC50 = 17.83 µl/l air and females: LC50 = 28.08 µl/l air at 48 h) and pulegone (males: LC50 = 23.04 µl/l air and females: LC50 = 38.25 µl/l air at 48 h). Binary combinations of these compounds were even more effective than single compounds, particularly the eugenol and carvacrol mixture, which resulted in 76.67% mortality in males and 63.33% in females at 48 h, and the 1,8-cineole and carvacrol combination, which produced 70.00% mortality in males and 60.00% in females. Interestingly, males C. maculatus were more susceptible to the treatments than females. These results highlight the potential of natural fumigants as environmentally friendly solutions for seed preservation and sustainable pest management.

Marine and terrestrial biostimulant elicitors of tolerance to cold stress

The increasing frequency of adverse environmental events, driven by ongoing climate change, has intensified the search for new technological alternatives in crop production and plant protection. Thermal stress can limit plant adaptation and negatively impact metabolism, physiology, morphology, and yield. Cold stress in plants has been extensively studied and can affect various stages of plant's life cycle, from seed formation to development, causing damage to cell membranes, impairing cell division, and disrupting water absorption. Consequently, researchers have focused on mitigating the impacts of abiotic stress by investigating bioactive molecules and biostimulants derived from various organisms, which enhance tolerance mechanisms in plants. In aquatic environments, macro- and microalgae have emerged as key sources of plant elicitors, providing extractable molecules such as polysaccharides, polyamines, polyphenols, and amino acids that enhance plant defense responses. Similarly, certain terrestrial plants have shown potential as sources of biostimulant compounds. Thus, this study aims to highlight advancements in crop systems by emphasizing the potential of algae-based and terrestrial biostimulant elicitors in enhancing tolerance to cold stress. Ultimately, the goal is to improve understanding of promising biological models for food production, fostering innovative developments that can contribute to economically and ecologically sustainable technologies.

Role of plant growth-promoting rhizobacteria in sustainable agriculture: Addressing environmental and biological challenges

This review underscores the importance of plant growth-promoting rhizobacteria (PGPR), fostering sustainability to address various environmental and biological issues. PGPR helps crops withstand salinity, nutrient deficiencies, and drought stress while tackling agricultural threats. Sustainable agriculture has emerged as a response to the social and economic problems farming practices face. Plants encounter obstacles from biotic stressors such as bacteria, viruses, nematodes, arachnids, and weeds that impede their growth. Furthermore, PGPR enhances plant growth through improved nutrient absorption and defense against pests. Bacillus subtilis utilizes indirect methods to combat diseases and protect plants from various diseases and pests. Additionally, PGPR acts as a bio-fertilizer that mitigates drought stress effects on crops in various regions worldwide. This review proposes strategies to boost productivity and improve bio-inoculant efficiency under real-world conditions. PGPR demonstrates its role in combating threats by influencing plant defense mechanisms, initiating systemic resistance responses, and regulating gene expression related to pathogen detection and defense signaling pathways. It maintains a balanced root microbiome by suppressing harmful microbial proliferation while promoting beneficial microbial interactions. Despite the challenges posed by technology and ethical considerations surrounding their modification, integrating PGPR into farming methods holds promise for sustainable agriculture. Given the increasing impact of climate change, PGPR plays a crucial role in improving crop resilience, enhancing soil quality, and reducing dependence on synthetic agricultural inputs.

Evaluation of Selected Plant Essential Oils for Aphid Pest Control in Integrated Pest Management

Aphids are major agricultural pests, feeding on plant sap and transmitting viruses to economically important crops. The use of synthetic pesticides is increasingly restricted due to stricter regulations aimed at protecting both human and environmental health. To address this challenge, we investigated the potential of essential oils (EOs) extracted from rosemary (Salvia rosmarinus Spenn.), laurel (Laurus nobilis L.), and cypress (Cupressus sempervirens L.) as alternatives to synthetic insecticides, while ensuring compatibility with biological control strategies. The EOs were extracted via hydrodistillation, diluted in acetone, and tested against the aphid Myzus persicae and its natural predator, the hoverfly (Sphaerophoria rueppellii). Aphid mortality was dose-dependent, reaching 85% with rosemary EO, 83% with laurel, and 81% with cypress. In contrast, hoverfly larvae mortality remained low, with a maximum of 20%, which could largely be attributed to the solvent used in the assays. These promising results support further research to develop effective EO-based tools for integrated pest management.

Aromatic Herbs as a Source of Bioactive Compounds: An Overview of Their Antioxidant Capacity, Antimicrobial Activity, and Major Applications

Many aromatic herbs are conventionally used for flavoring various foods, but receive wide attention because of the variety of health-related properties. The aromatic herbs can be used either fresh or as dried powders and in the form of extracts, essential oils, or purified metabolites. In this review, the main functional properties, in terms of antioxidant and antimicrobial properties, and the applications of some of the commonly used aromatic herbs from the Lamiaceae family, are discussed. Herbs like oregano, rosemary, sage, thyme, summer savory, marjoram, and basil possess high levels of bioactive phytochemicals. They are particularly rich in phenolic acids, flavones, phenolic diterpenes, and flavanones, with various beneficial effects. The phytochemical profile of aromatic plants is highly influenced by genetic factors, environmental conditions, and their interaction. In cases of the extracts and essential oils, the extraction method has a strong effect on the final composition of the herb products. Most of the applications of these aromatic herbs are related to their antioxidant, antimicrobial, and flavoring properties. In particular, aromatic herb extracts and essential oils have multiple applications in fields like food, feed, pharmaceutical, cosmetics, biopesticides, and textile industries.

Microfluidic Array Enables Rapid Testing of Natural Compounds Against Xylella fastidiosa

The bacterial pathogen Xylella fastidiosa (Xf), which causes several plant diseases with significant economic impacts on agriculture and the environment, remains a challenge to manage due to its wide host range. This study investigated the in vitro antibacterial effects of natural compounds, including Trametes versicolor extract, clove essential oil, and the resistance inducer FossilⓇ, against X. fastidiosa subsp. fastidiosa using an antibacterial susceptibility testing (AST) method based on microfluidic channels. This novel method was compared with the traditional broth macrodilution method to assess its reliability and the potential advantages microfluidics offers. For each substance and test, both the ability to limit planktonic growth (reported as the minimum inhibitory concentration) and the ability to inhibit biofilm formation were evaluated. The results suggest that compared to the macrodilution method, microfluidic channels allow for a more rapid AST execution, use less material, and allow for real-time observation of bacterial behavior under a continuous flow of nutrients and antibacterial substances. All tested products demonstrated high antibacterial efficacy against Xf with the macrodilution method, yielding comparable results with microfluidic AST. These findings highlight the antimicrobial properties of the tested substances and establish the groundwork for applying this new technique to select promising eco-friendly products for potential future field applications in controlling Xf.

Multi-stimuli-responsive pectin-coated dendritic mesoporous silica nanoparticles with Eugenol as a sustained release nanocarrier for the control of tomato bacterial wilt

BACKGROUND

Environmentally responsive nanoscale biocide delivery system enhances smart, regulated, and synergistic biocide application with precise biocide release. In this study, pectin-modified dendritic mesoporous silica nanoparticles (DMSNs) was used as a carrier to successfully construct a microenvironment-responsive (pH, temperature and enzyme) eugenol nano-biocide delivery system for the control of Ralstonia solanacearum infection.

RESULTS

The results showed that the specific surface area, pore size and surface activity of DMSNs significantly influence the biocide loading of eugenol, and the biocide loading capability was up to 72.50%. Eu@DMSNs/Pec had significant pH and pectinase stimulating effects, with varying release amounts under different temperature conditions. Compared with eugenol alone, Eu@DMSNs/Pec significantly enhanced the efficacy of eugenol. DMSNs assisted eugenol to induce peroxidation damage, produce ROS (•O2-, •OH and 1O2), achieve synergistic antibacterial effects, and had better rain erosion resistance and foliar retention rate based on pectin wettability and adhesion. Eu@DMSNs/Pec-FITC showed demonstrated efficient transport characteristics in tomato roots, stems and leaves, which enhanced the control effect on tomato bacterial wilt. In addition, Eu@DMSNs/Pec exert minimal influence on tomato seed germination and root growth, and have low toxicity to non-target organisms such as earthworms. Therefore, Eu@DMSNs/Pec environment-responsive nano-controlled release nanocarrier can effectively achieve accurate biocide release and reduce biocide dosage.

CONCLUSION

This work not only provides a pectin-modified DMSNs-based eugenol nanoscale biocide delivery system in response to specific environmental conditions of R. solanacearum infection but also elucidates the eugenol biocide loading, selective release ability and antibacterial mechanism of the system.

Larvicidal Efficacy of Chloris virgata Extracts Against Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus with Insights into Mode of Action via Molecular Docking

The indiscriminate use of synthetic insecticides for mosquito control has resulted in significant challenges, such as environmental pollution and growing insecticide resistance. In response, there is increasing interest in eco-friendly alternatives like plant-based larvicides. This study assesses the larvicidal efficacy of Chloris virgate (Poales: Poaceae) extracts against Aedes aegypti (Diptera: Culicidae), Culex quinquefasciatus (Diptera: Culicidae), and Anopheles stephensi (Diptera: Culicidae), and investigates the bioactive chemical compounds responsible for this activity. Soxhlet individual extraction was performed using n-hexane, chloroform, and ethanol, and methanol solvents are used separately to extract bioactive compounds from C. virgata. This approach allows for the selective extraction of specific compounds based on their solubility in each solvent. The extracts were tested on fourth instar larvae, and lethal concentrations (LC50 and LC90) were calculated via probit analysis. The methanol extract exhibited the lowest LC50 and LC90 values against Culex quinquefasciatus, with LC50 at 80.11 ppm and LC90 at 176.22 ppm, suggesting higher toxicity and effectiveness in larvicidal activity. Methanol extracts significantly affected mosquito larvae midguts, causing cytoplasmic thinning, muscle fiber disorganization, and brush border disruption. Gas chromatography-mass spectrometry (GC-MS) analysis identified major compounds such as stigmasterol, campesterol, and γ-sitosterol. Campesterol, 4.alpha.,14-Dimethyl-5.alpha, and Lanosterol showed strong binding affinities with acetylcholine esterase (5X61), exhibiting multiple hydrophobic interactions with key residues, including TRP 441, TYR 282, and CYS 447. Campesterol also displayed significant binding to Sterol Carrier Protein-2 (1PZ4) and Odorant-Binding Protein (3OGN) with several hydrophobic interactions, achieving binding affinities of - 10.1 kcal/mol and - 9.7 kcal/mol, respectively. This study highlights the potential of C. virgata methanol extracts as a promising eco-friendly larvicide for mosquito population management.

Tick Control Strategies: Critical Insights into Chemical, Biological, Physical, and Integrated Approaches for Effective Hard Tick Management

Ticks and tick-borne diseases significantly impact animal health, public health, and economic productivity globally, particularly in areas where the wildlife-livestock interface complicates management. This review critically examines the current control strategies, focusing on chemical, biological, physical, and integrated pest management (IPM) approaches. Chemical acaricides, while effective, are increasingly challenged by resistance development and environmental concerns. Biological approaches, including natural predators and entomopathogenic fungi, and physical interventions, such as habitat modification, provide sustainable alternatives but require further optimization. IPM stands out as the most promising long-term solution, integrating multiple approaches to enhance efficacy while reducing environmental risks. Emerging innovations, such as nanotechnology-enhanced acaricides and next-generation vaccines, offer promising avenues for improved tick control. Addressing the complex challenges of tick management requires tailored strategies, interdisciplinary collaboration, and sustained research investment in both veterinary and public health contexts.

Chemical composition and bio-efficacy of agro-waste plant extracts and their potential as bioinsecticides against Culex pipiens mosquitoes

Mosquitoes are considered one of the most lethal creatures on the planet and are responsible for millions of fatalities annually through the transmission of several diseases to humans. Green trash is commonly employed in agricultural fertilizer manufacturing and microbial bioprocesses for energy production. However, there is limited information available on the conversion of green waste into biocides. This study investigates the viability of utilizing green waste as a new biopesticide against Culex pipiens mosquito larvae. The current study found that plant extracts from Punica granatum (98.4 % mortality), Citrus sinensis (92 % mortality), Brassica oleracea (88 % mortality), Oryza sativa (81.6 % mortality), and Colocasia esculenta (53.6 % mortality) were very good at killing Cx. pipiens larvae 24 h post-treatment. The LC50 values were 314.43, 370.72, 465.59, 666.67, and 1798.03 ppm for P. granatum, C. sinensis, B. oleracea, O. sativa, and C. esculenta, respectively. All plant extracts, particularly P. granatum extract (14.93 and 41.87 U/g), showed a significant reduction in acid and alkaline phosphate activity. Additionally, pomegranate extract showed a significant decrease (90 %) in field larval density, with a stability of up to five days post-treatment. GC-MS results showed more chemical classes, such as terpenes, esters, fatty acids, alkanes, and phenolic compounds. HPLC analysis revealed that the analyzed extracts had a high concentration of phenolic and flavonoid components. Moreover, there are many variations among these plants in the amount of each compound. The docking interaction showed a simulation of the atomic-level interaction between a protein and a small molecule through the binding site of target proteins, explaining the most critical elements influencing the enzyme's activity or inhibitions. The study's findings showed that the various phytochemicals found in agro-waste plants had high larvicidal activity and provide a safe and efficient substitute to conventional pesticides for pest management, as well as a potential future in biotechnology.

Plant Oil Nano-Emulsions as a Potential Solution for Pest Control in Sustainable Agriculture

The increasing demand for sustainable and eco-friendly pest control methods has led to a growing interest in the development of novel, plant-based pesticides. In this study, we investigated the potential of nano-emulsions containing plant oils (Portulaca oleracea, Raphanus sativus, and Rosmarinus officinalis) as a new approach for controlling three major pests: Aphis gossypii, Spodoptera littoralis, and Tetranychus urticae. Using ultrasonication, we prepared stable and uniform nano-emulsions characterized by thermodynamic properties, dynamic light scattering (DLS), and transmission electron microscopy (TEM). The results showed that the nano-emulsions were effective in controlling the three pests, with the most potent activity observed against Aphis gossypii. Our findings suggest that plant oil nano-emulsions have the potential to be used as a sustainable and eco-friendly alternative to traditional pesticides. The use of these nano-emulsions could provide a new approach to manage pest populations, reducing the environmental impact of pesticide use, and promoting sustainable agriculture.

Harnessing the power of cinnamon oil: A review of its potential as natural biopesticide and its implications for food security

The escalating concerns about the environmental and health impacts of synthetic pesticides have intensified the search for sustainable and effective alternatives. Cinnamon oil, derived from the bark of Cinnamomum species, has emerged as a promising candidate in this arena due to its potent biopesticidal properties. This review explores the multifaceted role of cinnamon oil in agricultural pest management, emphasizing its potential to contribute significantly to food security. We discuss the bioactive components of cinnamon oil, their modes of action against various pests, and the effectiveness of cinnamon oil formulations. The review also addresses the challenges associated with the consistency and efficacy of cinnamon oil, its regulatory landscape, and the economic considerations for its use on a larger scale. By integrating findings from recent studies, this review underscores the viability of cinnamon oil as a cornerstone in future sustainable agricultural practices, aiming to reduce dependency on chemical pesticides and enhance global food security.

Endemic Yucatan Peninsula Plants with Pesticidal Potential: Herbarium-Based Literature Review

Agricultural pests present a significant challenge to humanity, often managed through synthetic chemicals that, when misused, can cause irreversible harm to both the environment and human health. This study focuses on endemic plants from the Yucatán Peninsula in Mexico, particularly from the state of Campeche, to identify their historical uses and propose an updated list of species with pesticide potential in the region. We systematically reviewed specimens from the Center for Sustainable Development and Wildlife Management (CEDESU) herbarium and local databases. Of the 3084 specimens collected, 2524 (81.84%) were from Campeche. The collection encompasses 106 botanical families, 459 genera, and 747 species. The study identified 201 plant species from 48 taxonomic families that are endemic to the Yucatán Peninsula Biotic Province (YPBP), of which 123 species are exclusive to the Mexican Yucatán Peninsula (MYP), representing 61.19% of the endemic species. Campeche contains 134 species (66.66%), distributed across 96 genera and 43 families. Notably, 46.26% of the species (62 species) belong to the Mexican region, with 8 species (12.90%) exclusive to Campeche. The research revealed that 27.90% of the families and 19.79% of the genera present in the state have been the subject of previous scientific studies regarding their use as pesticides. The most extensively studied families were Euphorbiaceae and Fabaceae. However, there is a notable lack of research on endemic plants from the Yucatán Peninsula, underscoring the need for increased attention to these species. The identified genera and families contain chemical compounds with activity against significant pests, demonstrating substantial potential for the development of natural pesticides.

Bioassay-Guided Fractionation Networking for Discovery of Biofungicides from Cultivated Salvia canariensis

Considering the detrimental impacts of the current pesticides on the biotic components of the biosphere, the development of novel pesticides is vital. Plant-derived biopesticides have emerged as popular alternatives to create a safer and more sustainable agriculture model. This study aims to validate the previous bioguided fractionation of endemic Canary Islands sage, Salvia canariensis, as a potential source of botanical pesticides using a cultivation process. Accordingly, the bioassay-guided fractionation of the ethanolic extract of the leaves of cultivated S. canariensis on the phytopathogenic fungal mycelia of Botrytis cinerea, Fusarium oxysporum, and Alternaria alternata yielded six known terpenoids. Their abietane diterpenoid-type (1-5) and sesquiterpenoid (6) structures were established based on spectroscopic and spectrometric analysis. This strategy identified one abietane diterpenoid, salviol (5), as a potential candidate for the future development of biofungicides with similar potency towards the assayed phytopathogenic fungi to commercial fungicides. Salviol worked in a concentration-dependent manner. Overall, this study reinforces the potential of abietane-type diterpenoids as promising agrochemical lead compounds against infectious diseases caused by phytopathogenic fungi and validates the cultivation of S. canariensis as a potential source of plant-derived biopesticides.

Antifungal activity of paeonol against Botrytis cinerea by disrupting the cell membrane and the application on cherry tomato preservation

Botrytis cinerea may cause gray mold in fruits and vegetables. Paeonol, an active component of traditional Chinese medicine, could suppress various microbial growth. However, reports on its effect on B. cinerea have not yet been documented. In this paper, we demonstrated that paeonol completely inhibited B. cinerea growth at 250 mg/L, corroborated by the observation of irregular morphological alterations in B. cinerea exposed to paeonol. Notably, the investigation of the operating mechanism revealed that paeonol induced cell death by disrupting the cell membrane, potentially mediated by the interaction between paeonol and ergosterol from the membrane. Further studies indicated that paeonol decreased ergosterol content and the expression of certain genes involved in ergosterol biosynthesis was significantly downregulated. In addition, paeonol treatment reduced the gray mold of cherry tomatoes. Meanwhile, compared to the control treatment, paeonol treatment could reduce weight loss and maintain higher contents of total soluble solid (TSS) and ascorbic acid, leading to a higher quality of the stored cherry tomato. Together, the data indicate that paeonol was effective as an alternative agent targeting disrupting the cell membrane to control gray mold and prolong the shelf life of cherry tomatoes, suggesting that paeonol could be used as a natural antifungal compound during postharvest storage.

Bacillus thuringiensis (Bt)-based biopesticide: Navigating success, challenges, and future horizons in sustainable pest control

The global demand for food production is escalating, necessitating innovative approaches to mitigate pest-related crop losses. Conventional pest management using synthetic pesticides has several drawbacks, promoting the search for eco-friendly alternatives such as biopesticides. Among these, Bacillus thuringiensis (Bt)-based biopesticides have emerged as a promising option due to their specificity, sustainability, and safety. This article reviews the success and application of Bt as a biopesticide, analysing its environmental impacts, formulation strategies, marketing trends and associated challenges. The environment impact of Bt is multifaceted, influencing soil ecosystems, plant-associated habitats, and non-target organisms. It interacts dynamically with soil invertebrates and affects both aquatic and terrestrial ecosystems, demonstrating a complex ecological footprint. The market for Bt-based biopesticide is expanding, driven by their proven efficacy and eco-friendliness with projections indicating continued growth. Despite the promising market trends, regulatory hurdles and formulation complexities remain significant obstacles. Addressing these challenges require collaborative efforts to streamline processes and enhance market acceptance. Nonetheless, the future of Bt-based biopesticide appears promising. Ongoing research is focused on advanced formulations, expanding the range of targeted pests and fostering regulatory cooperation, underscoring the pivotal role of Bt-based biopesticide in sustainable agriculture.

β-Caryophyllene oxide inhibits lysine acetylation of histones in Fusarium proliferatum to block ribosomal biosynthesis and function

The natural bicyclic sesquiterpene, β-Caryophyllene oxide (BCPO), has demonstrated inhibitory activity against Fusarium species. While previous studies have documented its antifungal properties through various biochemical mechanisms, the role of BCPO in modulating epigenetic modifications of DNA via histone deacetylases (HDACs) has received comparatively less attention. The study aims to elucidate how BCPO inhibits Fusarium proliferatum by affecting histone acetylation. Our results indicate that BCPO enhances FPRO_01165 (FpSIR2) enzyme activity to 6.01 ng/min/mg, representing a 55.30 % increase. Molecular docking analysis and molecular dynamics simulation confirmed the interaction between BCPO and FpSIR2. Furthermore, high concentrations (HC) of BCPO significantly inhibited the growth of F. proliferatum, resulting in marked reductions in H3K9ac and H3K27ac modification levels. We conducted chromatin immunoprecipitation sequencing (ChIP-seq) to identify enrichments of H3K9ac and H3K27ac, while also obtaining transcriptomic data from the HC treatment group. Combined analyses revealed that decreased levels of H3K9ac and H3K27ac primarily affected ribosomal pathways in F. proliferatum, leading to downregulation of several ribosomal genes and their corresponding proteins, such as RPL4, RPS19, and RPS16. Our findings suggest that BCPO stimulates both the production and activity of FpSIR2, which subsequently inhibits histone lysine acetylation in F. proliferatum. This inhibition suppresses ribosome biosynthesis and function as well as overall growth in this pathogen. The property of BCPO to reduce acetylation provides new insights for developing highly efficient yet low-toxicity antifungal agents.

A bibliometric analysis of biopesticides in corn pest management: Current trends and future prospects

This bibliographic review paper presents a comprehensive analysis of the scholarly literature on biopesticides utilized in corn pest management, employing a bibliometric approach to identify current trends and prospects in the field. The growing demand for sustainable agricultural practices has fueled interest in biopesticides as effective alternatives to conventional chemical pesticides. By systematically examining relevant publications, this review synthesizes the collective knowledge on biopesticide applications in corn production, encompassing various types of biopesticides, their modes of action, efficacy against key corn pests, and environmental considerations. The study synthesizes recent advances in microbial, botanical, and biochemical biopesticides such as Bacillus thuringiensis, neem extracts, and linalool, highlighting their specificity, minimal environmental impact, and potential to reduce pest resistance. It delves into the modes of action, including insecticidal activity, feeding disruption, and pest reproduction inhibition. The review also outlines an integrated pest management (IPM) strategy that combines biopesticides with agronomic practices, including crop rotation, biological control agents, and resistant crop varieties. This combined approach aims to enhance pest suppression, improve yield sustainability, and reduce chemical pesticide reliance. The findings provide valuable insights into sustainable corn pest management practices, promoting environmental conservation and agricultural productivity. Ultimately, this review aims to provide researchers, policymakers, and practitioners with a valuable resource for understanding the current landscape of biopesticides in corn pest management and guiding future research directions toward sustainable crop protection strategies.

Advances on Bioactive Metabolites with Potential for the Biocontrol of Plant Pathogenic Bacteria

The increase in the world population, which will be almost 10 billion by 2050, will require considerable efforts to significantly increase food production. Despite the considerable progress made in agriculture, this need is becoming an emergency due to desertification, environmental pollution and climate changes. Biotic stresses, such as pathogenic bacteria and fungi, primarily contribute to significant losses in agricultural productivity and compromise food safety. These harmful agents are predominantly managed using large quantities of synthetic pesticides. However, this widespread use has led to substantial environmental pollution, increased pest resistance and toxic residues in agricultural produce, which subsequently enter the food supply, posing severe health risks to humans and animals. These challenges have significantly driven the advancement of integrated pest management strategies to reduce or eliminate synthetic pesticides. A practical and viable alternative lies in biopesticides-methods developed from natural products that are safe for human and animal health. This approach aligns with the strong demand from consumers and public authorities for safer pest control solutions. This review was focused on the isolation, chemical and biological characterization of natural products for the biocontrol of phytopathogenic bacteria and, in some cases, fungi with potential eco-friendly applications.

Assessment of unintentional acute pesticide poisoning among smallholder vegetable farmers in Trinidad and Jamaica

Poisoning caused by pesticides is widely recognized as a major public health problem among smallholder farmers and rural communities, including in the Caribbean. However, a lack of quality data impedes understanding of the problem and hampers the development of effective strategies for its management. To better understand the prevalence of unintentional acute pesticide poisoning (UAPP) in Trinidad and Tobago and Jamaica and the pesticides and practices involved, we conducted a cross-sectional survey of 197 and 330 vegetable farmers in Trinidad and Jamaica, respectively. The findings from this study revealed a high incidence of self-reported health effects from occupational pesticide exposure, with 48 and 16% of respondents, respectively, experiencing symptoms of UAPP within the previous 12 months. Furthermore, the substantial proportion of UAPP incidents were associated with a few highly hazardous pesticides (HHPs), particularly lambda-cyhalothrin, acetamiprid, and profenofos in Jamaica, and alpha-cypermethrin, paraquat and lambda-cyhalothrin in Trinidad. Given the well-documented adverse effects of these chemicals on human health, the results of this study should be of significant concern to health authorities in Jamaica and Trinidad. This clearly indicates an urgent need for improved regulation and safer alternatives to the use of HHPs, as well as the promotion of alternatives. We provide policy recommendations and identify alternatives to HHPs for tropical vegetable production.

Insecticidal activity of extracts of handroanthus impetiginosus on Plutella xylostella (Lepidoptera: plutellidae) larvae

Plutella xylostella is considered the main pest of cabbage in Brazil and the world, causing damage of up to 100%. Thus, this study evaluated the insecticidal activity of extracts obtained from the fruits, seeds, bark, leaves, and flowers of Handroanthus impetiginosus against the diamondback moth, P. xylostella larvae. The seed extract showed the highest mortality (97.0%) compared to the control treatment. The LC50 values indicated that the seed and flower extracts (0.01003 and 0.01288 mg/L respectively) assumed the highest toxicity to P. xylostella larvae after 24 h of exposure. The results of this study indicated that the seeds extract is the most promising toxic extract, with measured mortality of approximately 97.0% for P. xylostella larvae after 144 h of exposure in kale plants. Seed extract showed the best insecticidal activity. Thus, this extract can be applied to develop an insecticide based on H. impetiginosus seed.

Mrlac1, an extracellular laccase, is required for conidial morphogenesis as well as the well adaptability in field of Metarhizium rileyi

Acting as an extremely promising fungal pesticide, Metarhizium rileyi exhibits robust insecticidal activity against Lepidoptera pests, particularly the larvae. Though there is a slight delay in efficacy, biopesticides offer salient advantages over traditional chemical pesticide especially in environmental safety, cyclic infection and resistant inhibition. In this study, an exterior T-DNA was randomly inserted into the genome of M. rileyi, resulting in the acquisition of a mutant strain that displayed a colour transition from green to yellow within its conidia. The disruption of Mrlac1, a laccase, has been confirmed to attribute to the epigenetic alterations. Mrlac1 is a secreted protein harboring an N-terminal signaling peptide that undergoes in vivo synthesis and accumulates on the cell wall of M. rileyi. Targeted knock-out mutant exhibited alterations not just in conidia coloration, but significantly diminished capacity to withstand external stressors, particularly non-biological factors such as high humidity, Congo red exposure, and UV radiation. The disruptant suffered a constraint on hyphal polar growth, alteration in conidial surface structure, as well as noticeable increase in adhesion forces between conidia, the core infection factors. There is a remarkable diminution in virulence of Mrlac1 deletion variant against larvae of Spodoptera litura by topical inoculation, but not hemolymph injection. Our findings suggest that Mrlac1 acts as a positive regulator in the normal morphogenesis of fungal conidia, encompassing pigment production, inter-conidia adhesion, and conidial cell wall integrity, while the preservation of these structures holds paramount importance for the survival and infection of M. rileyi in the field.

Impact of plant monoterpenes on insect pest management and insect-associated microbes

The fight against insect pests primarily relies on the utilization of synthetic insecticides. However, improper application of these chemicals can lead to detrimental effects on both the environment and human health, as well as foster the development of insect resistance. Consequently, novel strategies must be implemented to address the challenges stemming from the prolonged use of synthetic insecticides in agricultural and public health environments. Certain strategies involve the combination of crop protectants, which not only enhance insecticidal effectiveness but also reduce application rates. Plant-based natural products emerge as promising alternatives for insect management. Monoterpenes, which are abundant plant compounds produced through the activation of various enzymes, have attracted significant attention for their effectiveness in insect control. Notably, they are prolific in fragrance-producing plants. This review explores the plant defense, insecticidal, and antimicrobial characteristics of monoterpenes against insect pests, shedding light on their potential modes of action and possibilities for commercialization. Emphasizing their role as targeted and environmentally safer, the review highlights the practical viability of monoterpenes within integrated pest management programs.

An Ecofriendly Nature-Inspired Microcarrier for Enhancing Delivery, Stability, and Biocidal Efficacy of Phage-Based Biopesticides

In pursuit of sustainable agricultural production, the development of environmentally friendly and effective biopesticides is essential to improve food security and environmental sustainability. Bacteriophages, as emerging biocontrol agents, offer an alternative to conventional antibiotics and synthetic chemical pesticides. The primary challenges in applying phage-based biopesticides in agricultural settings are their inherent fragility and low biocidal efficacy, particularly the susceptibility to sunlight exposure. This study addresses the aforementioned challenges by innovatively encapsulating phages in sporopollenin exine capsules (SECs), which are derived from plant pollen grains. The size of the apertures on SECs could be controlled through a non-thermal and rapid process, combining reinflation and vacuum infusion techniques. This unique feature facilitates the high-efficiency encapsulation and controlled release of phages under various conditions. The proposed SECs could encapsulate over 9 log PFU g-1 of phages and significantly enhance the ultraviolet (UV) resistance of phages, thereby ensuring their enhanced survivability and antimicrobial efficacy. The effectiveness of SECs encapsulated phages (T7@SECs) in preventing and treating bacterial contamination on lettuce leaves is further demonstrated, highlighting the practical applicability of this novel biopesticide in field applications. Overall, this study exploits the potential of SECs in the development of phage-based biopesticides, presenting a promising strategy to enhancing agricultural sustainability.

Natural Rubrolides and Their Synthetic Congeners as Inhibitors of the Photosynthetic Electron Transport Chain

Rubrolides are a family of naturally occurring 5-benzylidenebutenolides, which generally contain brominated phenol groups, and nearly half of them also present a chlorine attached to the butenolide core. Seven natural rubrolides were previously synthesized. When these compounds were tested against the model plant Raphanus sativus, six were found to exert a slight inhibition on plant growth. Aiming to exploit their scaffold as a model for the synthesis of new compounds targeting photosynthesis, nine new rubrolide analogues were prepared. The synthesis was accomplished in 2-4 steps with a 10-39% overall yield from 3,4-dichlorofuran-2(5H)-one. All compounds were evaluated for their ability to inhibit the whole Hill reaction or excluding photosystem I (PSI). Several natural rubrolides and their analogues displayed good inhibitory potential (IC50 = 2-8 μM). Molecular docking studies on the photosystem II-light harvesting complex II (PSII-LHCII supercomplex) binding site were also performed. Overall, data support the use of rubrolides as a model for the development of new active principles targeting the photosynthetic electron transport chain to be used as herbicides.

Binding of green tea epigallocatechin gallate to the arginine kinase active site from the brown recluse spider (Loxosceles laeta): A potential synergist to chemical pesticides

Loxosceles spp. spiders can cause serious public health issues. Chemical control is commonly used, leading to health and environmental problems. Identifying molecular targets and using them with natural compounds can help develop safer and eco-friendlier biopesticides. We studied the kinetics and predicted structural characteristics of arginine kinase (EC 2.7.3.3) from Loxosceles laeta (LlAK), a key enzyme in the energy metabolism of these organisms. Additionally, we explored (-)-epigallocatechin gallate (EGCG), a green tea flavonoid, as a potential lead compound for the LlAK active site through fluorescence and in silico analysis, such as molecular docking and molecular dynamics (MD) simulation and MM/PBSA analyses. The results indicate that LlAK is a highly efficient enzyme (K m Arg 0.14 mM, K m ATP 0.98 mM, k cat 93 s-1, k cat/K m Arg 630 s-1 mM-1, k cat/K m ATP 94 s-1 mM-1), which correlates with its structure similarity to others AKs (such as Litopenaeus vannamei, Polybetes pythagoricus, and Rhipicephalus sanguineus) and might be related to its important function in the spider's energetic metabolism. Furthermore, the MD and MM/PBSA analysis suggests that EGCG interacted with LlAK, specifically at ATP/ADP binding site (RMSD <1 nm) and its interaction is energetically favored for its binding stability (-40 to -15 kcal/mol). Moreover, these results are supported by fluorescence quenching analysis (K d 58.3 μM and K a 1.71 × 104 M-1). In this context, LlAK is a promising target for the chemical control of L. laeta, and EGCG could be used in combination with conventional pesticides to manage the population of Loxosceles species in urban areas.

Aloe vera-An Extensive Review Focused on Recent Studies

Since ancient times, Aloe vera L. (AV) has attracted scientific interest because of its multiple cosmetic and medicinal properties, attributable to compounds present in leaves and other parts of the plant. The collected literature data show that AV and its products have a beneficial influence on human health, both by topical and oral use, as juice or an extract. Several scientific studies demonstrated the numerous biological activities of AV, including, for instance, antiviral, antimicrobial, antitumor, and antifungal. Moreover, its important antidepressant activity in relation to several diseases, including skin disorders (psoriasis, acne, and so on) and prediabetes, is a growing field of research. This comprehensive review intends to present the most significant and recent studies regarding the plethora of AV's biological activities and an in-depth analysis exploring the component/s responsible for them. Moreover, its morphology and chemical composition are described, along with some studies regarding the single components of AV available in commerce. Finally, valorization studies and a discussion about the metabolism and toxicological aspects of this "Wonder Plant" are reported.

Production and characterization of Trichoderma asperellum chitinases and their use in synergy with Bacillus thuringiensis for lepidopteran control

BACKGROUND

Despite their known negative effects on ecosystems and human health, synthetic pesticides are still largely used to control crop insect pests. Currently, the biopesticide market for insect biocontrol mainly relies on the entomopathogenic bacterium Bacillus thuringiensis (Bt). New biocontrol tools for crop protection might derive from fungi, in particular from Trichoderma spp., which are known producers of chitinases and other bioactive compounds able to negatively affect insect survival.

RESULTS

In this study, we first developed an environmentally sustainable production process for obtaining chitinases from Trichoderma asperellum ICC012. Then, we investigated the biological effects of this chitinase preparation - alone or in combination with a Bt-based product - when orally administered to two lepidopteran species. Our results demonstrate that T. asperellum efficiently produces a multi-enzymatic cocktail able to alter the chitin microfibril network of the insect peritrophic matrix, resulting in delayed development and larval death. The co-administration of T. asperellum chitinases and sublethal concentrations of Bt toxins increased larval mortality. This synergistic effect was likely due to the higher amount of Bt toxins that passed the damaged peritrophic matrix and reached the target receptors on the midgut cells of chitinase-treated insects.

CONCLUSION

Our findings may contribute to the development of an integrated pest management technology based on fungal chitinases that increase the efficacy of Bt-based products, mitigating the risk of Bt-resistance development. © 2024 Society of Chemical Industry.

Discovery of Antibacterial Compounds against Xanthomonas citri subsp. citri from a Marine Fungus Aspergillus terreus SCSIO 41202 and the Mode of Action

Citrus canker, caused by Xanthomonas citri subsp. citri (Xcc), is a severe citrus disease. Currently, copper-containing pesticides are widely used to manage this disease, posing high risks to the environment and human health. This study reports the discovery of naturally occurring anti-Xcc compounds from a deep-sea fungus, Aspergillus terreus SCSIO 41202, and the possible mode of action. The ethyl acetate extract of A. terreus was subjected to bioassay-guided isolation, resulting in the discovery of eight anti-Xcc compounds (1-8) with minimum inhibitory concentrations (MICs) ranging from 0.078 to 0.625 mg/mL. The chemical structures of these eight metabolites were determined by integrative analysis of various spectroscopic data. Among these compounds, Asperporonin A (1) and Asperporonin B (2) were identified as novel compounds with a very unusual structural skeleton. The electronic circular dichroism was used to determine the absolute configurations of 1 and 2 through quantum chemical calculation. A bioconversion pathway involving pinacol rearrangement was proposed to produce the unusual compounds (1-2). Compound 6 exhibited an excellent anti-Xcc effect with a MIC value of 0.078 mg/mL, which was significantly more potent than the positive control CuSO4 (MIC = 0.3125 mg/mL). Compound 6 inhibited cell growth by disrupting biofilm formation, destroying the cell membrane, and inducing the accumulation of reactive oxygen species. In vivo tests indicated that compound 6 is highly effective in controlling citrus canker disease. These results indicate that compounds 1-8, especially 6, have the potential as lead compounds for the development of new, environmentally friendly, and efficient anti-Xcc pesticides.

Actinomycetes are a natural resource for sustainable pest control and safeguarding agriculture

Actinomycetes, a diverse group of bacteria with filamentous growth characteristics, have long captivated researchers and biochemists for their prolific production of secondary metabolites. Among the myriad roles played by actinomycete secondary metabolites, their historical significance in the field of biocontrol stands out prominently. The fascinating journey begins with the discovery of antibiotics, where renowned compounds like streptomycin, tetracycline, and erythromycin revolutionized medicine and agriculture. The history of biocontrol traces its roots back to the early twentieth century, when scientists recognized the potential of naturally occurring agents to combat pests and diseases. The emergence of synthetic pesticides in the mid-twentieth century temporarily overshadowed interest in biocontrol. However, with growing environmental concerns and the realization of the negative ecological impacts of chemical pesticides, the pendulum swung back towards exploring sustainable alternatives. Beyond their historical role as antibiotics, actinomycete-produced secondary metabolites encompass a rich repertoire with biopesticide potential. The classification of these compounds based on chemical structure and mode of action is highlighted, demonstrating their versatility against both plant pathogens and insect pests. Additionally, this review provides in-depth insights into how endophytic actinomycete strains play a pivotal role in biocontrol strategies. Case studies elucidate their effectiveness in inhibiting Spodoptera spp. and nematodes through the production of bioactive compounds. By unraveling the multifunctional roles of endophytic actinomycetes, this review contributes compelling narrative knowledge to the field of sustainable agriculture, emphasizing the potential of these microbial allies in crafting effective, environmentally friendly biocontrol strategies for combating agricultural pests.

Efficacy of Essential Oil Vapours in Reducing Postharvest Rots and Effect on the Fruit Mycobiome of Nectarines

Nectarines can be affected by many diseases, resulting in significant production losses. Natural products, such as essential oils (EOs), are promising alternatives to pesticides to control storage rots. This work aimed to test the efficacy of biofumigation with EOs in the control of nectarine postharvest diseases while also evaluating the effect on the quality parameters (firmness, total soluble solids, and titratable acidity) and on the fruit fungal microbiome. Basil, fennel, lemon, oregano, and thyme EOs were first tested in vitro at 0.1, 0.5, and 1.0% concentrations to evaluate their inhibition activity against Monilinia fructicola. Subsequently, an in vivo screening trial was performed by treating nectarines inoculated with M. fructicola, with the five EOs at 2.0% concentration by biofumigation, performed using slow-release diffusers placed inside the storage cabinets. Fennel, lemon, and basil EOs were the most effective after storage and were selected to be tested in efficacy trials using naturally infected nectarines. After 28 days of storage, all treatments showed a significant rot reduction compared to the untreated control. Additionally, no evident phytotoxic effects were observed on the treated fruits. EO vapors did not affect the overall quality of the fruits but showed a positive effect in reducing firmness loss. Metabarcoding analysis showed a significant impact of tissue, treatment, and sampling time on the fruit microbiome composition. Treatments were able to reduce the abundance of Monilinia spp., but basil EO favored a significant increase in Penicillium spp. Moreover, the abundance of other fungal genera was found to be modified.

Mentha spp. essential oils: toxicity to Alphitobius diaperinus, activity against poultry pathogenic bacteria, and Beauveria bassiana compatibility

The botanical insecticide market is growing because of limitations placed on the use of certain synthetic chemical insecticides. In this sense, the lesser mealworm Alphitobius diaperius (Coleoptera: Tenebrionidae) is the main poultry pest. The insect causes weight loss and damage to the digestive system of poultry, and it is a vector and reservoir of pathogens. Consequently, this study explored the following hypotheses: (i) essential oils (EOs) derived from Mentha spp. are toxic to A. diaperius; (ii) these EOs are compatible with Beauveria bassiana, the natural enemy of the poultry pest, that parasite A. diaperinus; (iii) these EOs also exhibit activity against bacteria that are pathogenic to poultry. In topical applications and ingestion tests, EOs from Mentha arvensis, Mentha spicata, and Mentha piperita were toxic to A. diaperinus. Chromatographic analyses revealed that menthol is the predominant compound in M. arvensis and M. piperita, whereas carvone is the major compound in M. spicata. Both (-)- and (+)-menthol, along with (-)- and (+)-carvone, underwent testing with A. diaperinus. Nevertheless, their activity was not as potent as those of the EOs, suggesting a possible synergistic and/or additive effect. The EOs did not have any adverse effects on the conidial germination, vegetative growth, or conidia production per colony of the entomopathogenic fungus B. bassiana. Consequently, these EOs are compatible with this natural enemy. The EO extracted from M. spicata exhibited significant toxicity against Staphylococcus aureus (ATCC 25923), whereas the remaining EOs displayed moderate toxicity against this bacterium. The EOs derived from Mentha spp., as assessed in this study, hold promise for the development of botanical insecticides tailored for the control of A. diaperinus. These insecticides are selective in favor of the natural enemy B. bassiana and can also serve as effective sanitizers, thanks to their antibacterial properties.

Neotropical Flora's Contribution to the Development of Biorational Products for Drosophila suzukii Control

Essential oils (EOs) produced by aromatic plants belonging to different families, such as Asteraceae, Lamiaceae, Lauraceae, Myrtaceae, and Piperaceae, are generally suggested as potential sources of new molecules with insecticidal activity. The EOs are constituted bioactive molecules that may have to control Drosophila suzukii (Matsumura), a serious economic invasive pest of small fruits worldwide. Currently, the control strategy against D. suzukii depends especially on treatment with synthetic insecticides. Due to impacts to human health and the environment, efforts have been made to seek efficient insecticides in chemical pest control. Thus, sixty-five oils extracted from plants were selected to find new alternative types of insecticides active against D. suzukii. The monoterpenes, such as limonene, α-pinene, 1,8-cineole, linalool, menthol, geranial, and neral, were the most representative, which stand out for their insecticidal efficiency. The OEs demonstrated to be used in the management of D. suzukii, thus being an effective strategy to control this pest, ensuring crop protection and agricultural sustainability. Therefore, the substitution by natural products or eco-friendly pesticides instead of synthetic pesticides represents a notable option to mitigate harmful effects on human health and the environment.

Bio-guided isolation of aromatic abietane diterpenoids from Salvia canariensis as biopesticides in the control of phytopathogenic fungi

BACKGROUND

Biofungicides arise as a promising alternative to the indiscriminate use of harmful synthetic fungicides in crop management.

RESULTS

The present study reports the bio-guided fractionation of an endemic plant from the Canary Islands, Salvia canariensis against the phytopathogens, Alternaria alternata, Botrytis cinerea, and Fusarium oxysporum. This procedure allowed identifying a series of diterpenoids with an abietane skeleton (1-5), which exhibited remarkable activity against the phytopathogenic fungi assayed. Their structures were established by means of spectroscopic and spectrometric methods, as well as comparison with reported data. Compounds 2 (carnosic acid), 4 (11-acetoxy carnosic acid) and 5 (11,12-diacetoxy carnosic acid) showed significant mycelium growth inhibition (%GI > 50 at 0.1 mg/mL concentration) on all the assayed fungi, and with a potency also higher than the positive control, Fosbel-Plus, a fungicide commonly used in agriculture. A preliminary structure-activity relationship is also discussed.

CONCLUSIONS

These findings underline the aromatic abietane diterpenoids as promising eco-friendly alternatives to conventional fungicides to use in integrated pest management. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Natural Pyrethrin-Induced Oxidative Damage in Human Liver Cells through Nrf-2 Signaling Pathway

Natural pyrethrins (NPs), one kind of bio-pesticide, have been widely used in organic agriculture and ecological environment studies. Studies have shown that NPs may affect the metabolism of rat liver and human hepatocytes; nevertheless, the toxic effects of NPs on the liver and the related mechanisms are still incompletely understood. In this research, we utilized three types of human liver cells to investigate the mechanism of NPs' induction of oxidative stress. The results showed that NPs exhibit noteworthy cytotoxic effects on human liver cells. These effects are characterized by the induction of LDH release, mitochondrial collapse, and an increased production of ROS and MDA content, subsequently activating the Kelch-like ECH-associated protein 1/Nuclear factor erythroid 2- related factor 2 (Keap1/Nrf-2) pathway. The ROS inhibitor N-acetyl-L-cysteine (NAC) can alleviate ROS/Nrf2-mediated oxidative stress. In addition, the siRNA knockdown of Nrf-2 exacerbated the injury, including ROS production, and inhibited cell viability. In summary, the ROS-mediated Keap1/Nrf-2 pathway could be an important regulator of NP-induced damage in human liver cells, which further illustrates the hepatotoxicity of NPs and thereby contributes to the scientific basis for further exploration.

3D Printing Technology: Role in Safeguarding Food Security

The rising threats to food security include several factors, such as population growth, low agricultural investment, and poor distribution systems. Consequently, food insecurity results from a confluence of issues, including diseases, processing limitations, and distribution deficiencies. Food insecurity usually occurs in vulnerable areas where certain technologies and traditional food safety testing are not a viable solution for foodborne disease detection. In this regard, 3D printing technologies and 3D printed sensors open the platform to produce portable, accurate, and low-cost sensors that address the gaps and challenges in food security. In this paper, we discuss the perspective role of 3D printed sensors in food security in terms of food safety and food quality monitoring to provide reliable access to nutritious, affordable food. In each section, we highlight the advantages of 3D printing technology in terms of cost-effectiveness, accuracy, accessibility, and reproducibility compared to traditional manufacturing methodologies. Recent developments in robotic technologies for mechanization, such as food handling with soft grippers, are also discussed. Lastly, we delve into the applications of advanced 3D printing technologies in agricultural monitoring, particularly the future of plant wearables, environmental sensing, and overall plant health monitoring.

Seeds of nonhost species as sources of toxic compounds for the cowpea weevil Callosobruchus maculatus (F.)

Cowpea weevil, Callosobruchus maculatus, is the primary pest of stored cowpea seeds. The management of this infestation currently relies on insecticides, resulting in environmental pollution and selection of insecticide-resistant pests. Consequently, research efforts are being devoted to identify natural insecticides as sustainable and environment friendly alternatives for the control of C. maculatus. In this study, we explore the toxic effects of the nonhost seeds Parkia multijuga, Copaifera langsdorffii, Ormosia arborea, Amburana cearensis, Lonchocarpus guilleminianus, Sapindus saponaria, and Myroxylon peruiferum, on the cowpea weevil C. maculatus. Notably, all nonhost seeds led to reductions between 60 and 100% in oviposition by C. maculatus females. Additionally, the larvae were unable to penetrate the nonhost seeds. Artificial seeds containing 0.05% to 10% of cotyledon flour were toxic to C. maculatus larvae. Approximately 40% of larvae that consumed seeds containing 0.05% of O. arborea failed to develop, in contrast to control larvae. Proteomic analysis of A. cearensis and O. arborea seeds identify revealed a total of 371 proteins. From those, 237 are present in both seeds, 91 were exclusive to O. arborea seeds, and 43 were specific to A. cearensis seeds. Some of these proteins are related to defense, such as proteins containing the cupin domain and 11S seed storage protein. The in silico docking of cupin domain-containing proteins and 11S storage protein with N-acetylglucosamine (NAG)4 showed negative values of affinity energy, indicating spontaneous binding. These results showed that nonhost seeds have natural insecticide compounds with potential to control C. maculatus infestation.

Identification and potential application of key insecticidal metabolites in Tilia amurensis, a low-preference host of Hyphantria cunea

Developing effective insecticidal strategies is an important means of reducing the spread and host plant damage by Hyphantria cunea. In this study, key metabolites with insecticidal activity against H. cunea were screened by targeted metabolomics in Tilia amurensis, a low-preference host plant. Subsequently, the potential of key metabolites that could be used as botanical pesticides was evaluated. The results showed that coumarin was the key insecticidal metabolite of T. amurensis and had a significant insecticidal effect and weight inhibition effect on H. cunea larvae. Coumarin treatment significantly decreased the larval nutrient content and the gene expression of rate-limiting enzymes in the glycolytic pathway and tricarboxylic acid cycle. A significantly enhanced detoxification enzyme activity (CarE and GST), antioxidant oxidase activity (SOD and CAT), non-enzymatic antioxidant levels (GSH), and total antioxidant capacity were observed in coumarin-treated larvae. Coumarin treatment resulted in a significant increase in the expression levels of detoxification enzyme genes (CarE1, CarE2, CarE3, GST2, and GST3) and antioxidant oxidase genes (SOD1, CAT1, and CAT2) in H. cunea larvae. Coumarin treatment significantly increased the levels of MDA and H2O2 in larvae but did not cause pathological changes in the ultrastructure of the larval midgut. Coumarin solution sprayed directly or as a microcapsule suspension formulation with coumarin as the active ingredient had significant insecticidal activity against the H. cunea larvae. Overall, coumarin, a key anti-insect metabolite identified from T. amurensis, can significantly inhibit the growth and survival of H. cunea larvae and has the potential to be developed as a botanical pesticide.

Comprehensive phytochemical profiles and antioxidant activity of Korean local cultivars of red chili pepper (Capsicum annuum L.)

Red chili pepper (Capsicum annuum L.), which belongs to the Solanaceae family, contains a variety of phytochemicals with health-promoting properties including capsaicinoids, phenolics and fatty acids. Red chili pepper is one of the most consumed vegetables in Korea and occupies the largest cultivated area among spices. In this study, the ethanolic extracts from two Korean local cultivars, namely Subicho and Eumseong, were analyzed using a hybrid trapped ion mobility Q-TOF mass spectrometer equipped with a UPLC system, and their phytochemical profiles were then compared with those of a common phytophthora disease-resistant cultivar called Dokbulwang, which is extensively used for red chili pepper powder in public spaces across Korea. Utilizing high-resolution ion-mobility Q-TOF MS analysis, 458 and 192 compounds were identified from the three different red chili peppers in positive and negative ion modes, respectively, by matching with a reference spectral library. Principal component analysis revealed clear distinctions among the three cultivars, allowing us to identify key phytochemical components responsible for discriminating the local cultivars from the public cultivar. Furthermore, the assessment of total flavonoid, phenolic, and antioxidant activity in the red pepper extracts, highlighted their diverse molecular and chemical profiles. Despite the higher total flavonoid and phenolic content values observed in the public cultivar, the radical scavenging rate was higher in the local cultivars, particularly in Subicho. This suggest the presence of stronger antioxidant compounds in the local cultivar, indicating their potential health benefits due to their rich content of bioactive compounds. Notably, the local cultivars exhibited significantly higher proportions of organic compounds (more than four times) and terpenoids (more than two times) compared to the public cultivar. Specifically, higher levels of five major capsaicinoid compounds were found in the local cultivars when compared to the public cultivar. The observed disparities in phytochemical composition and antioxidant activities indicate the molecular diversity present among these cultivars. Further exploration of the bioactive compounds in these local cultivars could prove invaluable for the development of native crops, potentially leading to the discovery of novel sources of bioactive molecules for various applications in health and agriculture.

Ethnobotanical study of medicinal plants used by the people of Mosop, Nandi County in Kenya

Background: Throughout the history, nature has provided mankind with most of their basic needs, which include food, shelter, medicine, clothes, flavours, scents as well as raw materials. Given that they are an integral part of cultural heritage, medicinal plants have played a significant role in human healthcare systems around the world. Investigating various biological resources for use as medicines requires ethnomedicinal studies. Methods: Data on utilization of ethnomedicinal plants from local healers in Kenya's Mosop Sub-County in Nandi County was documented through open-ended, semi-structured questionnaires. A number of quantitative indices, such as the Use Citation (UC), Informant Consensus Factor (ICF), Use Value (UV), Frequency of Citation (FoC) and Relative Frequency of Citation (RFC) were used to convey the potential medical benefits, vitality and variety of the ethnomedicine. Results: 102 informants provided information on 253 ethnomedicinal plant species, classified into 74 families. There were 249 native plant species identified, along with few exotic species: Senegalia senegal (L.) Britton, Persea americana Mill, Carica papaya L. and Solanum betaceum Cav. Of all recorded species, 32% and 27% were herbs and trees, respectively. Among plant parts, leaves were most frequently utilized (27%) and roots (26%), while decoctions (21%) were the most widely used formulations. The dominant family was Asteraceae, with 28 species, followed by Lamiaceae, with 19 species. The highest ICF value was 0.778 for a number of parasitic and infectious illnesses, including ringworms, athlete's foot rot, tetanus, typhoid, intestinal parasites, abscesses, malaria, and amoebiasis. The study's data validates the region's widespread use of traditional medicinal plant remedies. Conclusion: The current study will lay a foundation of knowledge for future research investigations. The abundance of knowledge regarding ethnomedicinal species and their medicinal applications will stimulate further phytochemical and pharmacological research, which could lead to the discovery of potentially significant pharmaceuticals.

Dissipation, Residue and Human Dietary Risk Assessment of Pyraclostrobin and Cyazofamid in Grapes Using an HPLC-UV Detector

Pyraclostrobin is a new broad-spectrum methoxyacrylic acid fungicide. Cyazofamid is a new selective foliar spray acaricide. Here, we studied the degradation rate and final residues of pyraclostrobin and cyazofamid in grape and evaluated their dietary risk to consumers. The average recoveries of pyraclostrobin ether ester, cyazofamid and cyazofamid metabolite (CCIM) in grapes were 84-94%, 92-98% and 99-104%, respectively. The relative standard deviations (RSDs) were 6.0-20.3%, 2.4-10.5% and 1.3-4.0%, respectively, and the LOQs were all 0.05 mg/kg. The digestion dynamics of the experimental sites were in accordance with the first-order kinetic equation. The degradation half-lives of pyraclostrobin ether ester and cyazofamid were 17.8 d-28.9 d and 4.3 d-7.8 d, respectively. The final residues of pyraclostrobin ether ester, cyazofamid and CCIM in grapes were <0.05-1.88 mg/kg, <0.05-0.31 mg/kg and <0.05-0.47 mg/kg, respectively. Using probability models, the total chronic risk values for pyraclostrobin and cyazofamid were calculated to be 0.112-189.617% and 0.021-1.714%, respectively. The results of the contribution analysis indicate that pyraclostrobin poses a much greater risk to Chinese consumers than cyazofamid, especially to children and adolescents, who have a significantly greater risk than adults. This suggests that more consideration should be given to the cumulative risk of compounds for vulnerable groups in the future.

Screening of Secondary Metabolites Produced by Nigrospora sphaerica Associated with the Invasive Weed Cenchrus ciliaris Reveals Two New Structurally Related Compounds

In the search for new alternative biocontrol strategies, phytopathogenic fungi could represent a new frontier for weed management. In this respect, as part of our ongoing work aiming at using fungal pathogens as an alternative to common herbicides, the foliar pathogen Nigrospora sphaerica has been evaluated to control buffelgrass (Cenchrus ciliaris). In particular, in this work, the isolation and structural elucidation of two new biosynthetically related metabolites, named nigrosphaeritriol (3-(hydroxymethyl)-2-methylpentane-1,4-diol) and nigrosphaerilactol (3-(1-hydroxyethyl)-4-methyltetrahydrofuran-2-ol), from the phytotoxic culture filtrate extract were described, along with the identification of several known metabolites. Moreover, the absolute stereochemistry of (3R,4S,5S)-nigrosphaerilactone, previously reported as (3S,4R,5R)-4-hydroxymethyl-3,5-dimethyldihydro-2-furanone, was determined for the first time by X-ray diffraction analysis. Considering their structural relationship, the determination of the absolute stereochemistry of nigrosphaerilactone allowed us to hypothesize the absolute stereochemistry of nigrosphaeritriol and nigrosphaerilactol.

Present status of insecticide impacts and eco-friendly approaches for remediation-a review

Insecticides are indispensable for modern agriculture to ensuring crop protection and optimal yields. However, their excessive use raises concerns regarding their adverse effects on agriculture and the environment. This study examines the impacts of insecticides on agriculture and proposes remediation strategies. Excessive insecticide application can lead to the development of resistance in target insects, necessitating higher concentrations or stronger chemicals, resulting in increased production costs and disruption of natural pest control mechanisms. In addition, non-target organisms, such as beneficial insects and aquatic life, suffer from the unintended consequences of insecticide use, leading to ecosystem imbalances and potential food chain contamination. To address these issues, integrated pest management (IPM) techniques that combine judicious insecticide use with biological control and cultural practices can reduce reliance on chemicals. Developing and implementing selective insecticides with reduced environmental persistence is crucial. Promoting farmer awareness of responsible insecticide use, offering training and resources, and adopting precision farming technologies can minimize overall insecticide usage.