Search Results (465)

The extensive use of pesticides has significant implications for public health and the environment. Breeding crop plants is the most effective and environmentally friendly approach to improve the plants’ resistance. However, it is time-consuming and costly, and it is sometimes difficult to achieve satisfactory results. Plants induce defense responses to natural elicitors by interpreting multiple genes that encode proteins, including enzymes, secondary metabolites, and pathogenesis-related (PR) proteins. These responses characterize systemic acquired resistance. Humic substances trigger positive local and systemic physiological responses through a complex network of hormone-like signaling pathways and can be used to induce biotic and abiotic stress resistance. This study aimed to assess the effect of humic substances on the activity of phenylalanine ammonia-lyase (PAL), peroxidase (POX), and β-1,3-glucanase (GLU) used as a resistance marker in various plant species, including orange, coffee, sugarcane, soybeans, maize, and tomato. Seedlings were treated with a dilute aqueous suspension of humic substances (4 mM C L⁻¹) as a foliar spray or left untreated (control). Leaf tissues were collected for enzyme assessment two days later. Humic substances significantly promoted the systemic acquired resistance marker activities compared to the control in all independent assays. Overall, all enzymes studied in this work, PAL, GLUC, and POX, showed an increase in activity by 133%, 181%, and 149%, respectively. Among the crops studied, citrus and coffee achieved the highest activity increase in all enzymes, except for POX in coffee, which showed a decrease of 29% compared to the control. GLUC exhibited the highest response to HS treatment, the enzyme most prominently involved in increasing enzymatic activity in all crops. Plants can improve their resistance to pathogens through the exogenous application of HSs as this promotes the activity of enzymes related to plant resistance. Finally, we consider the potential use of humic substances as a natural chemical priming agent to boost plant resistance in agriculture Full article

Glutathione S-transferases (GSTs) are phase II detoxification enzymes that display several enzymatic activities, including transferase, peroxidase, reductase, and isomerase functions, as well as non-enzymatic roles (e.g., serving as binding proteins). Their complex functionality lies in the biotransformation of xenobiotics (e.g., pesticides, drugs) and certain endogenous compounds, primarily metabolites produced by phase I detoxification enzymes. Several plant-derived compounds have been shown to modulate the activity and expression levels of these enzymes. Phytochemical activators of GSTs are potentially beneficial for detoxification in cases of exposure to various toxic compounds, whereas inhibitors of GSTs could have positive effects as adjuvant treatments for cancers that express high levels of GSTs associated with drug resistance. Full article

Restricting the use of chemical pesticides in forestry requires the search for alternative solutions. These could be volatile organic compounds produced by three investigated species of bacteria (Bacillus amyloliquefaciens (ex Fukumoto) Priest, B. subtilis (Ehrenberg) Cohn and B. thuringiensis Berliner), which inhibit the growth of the pathogen F. oxysporum Schltdl. emend. Snyder & Hansen in forest nurseries. The highest inhibition of fungal growth (70%) was observed with B. amyloliquefaciens after 24 h of antagonism test, which had a higher content of carbonyl compounds (46.83 ± 8.41%) than B. subtilis (41.50 ± 6.45%) or B. thuringiensis (34.62 ± 4.77%). Only in the volatile emissions of B. amyloliquefaciens were 3-hydroxybutan-2-one, undecan-2-one, dodecan-5-one and tetradecan-5-one found. In contrast, the main components of the volatile emissions of F. oxysporum were chlorinated derivatives of benzaldehyde (e.g., 3,5-dichloro-4-methoxybenzaldehyde) and chlorinated derivatives of benzene (e.g., 1,4-dichloro-2,5-dimethoxybenzene), as well as carbonyl compounds (e.g., benzaldehyde) and alcohols (e.g., benzyl alcohol). Further compounds were found in the interactions between B. amyloliquefaciens and F. oxysporum (e.g., $\alpha$-cubebene, linalool, undecan-2-ol, decan-2-one and 2,6-dichloroanisole). Specific substances were found for B. amyloliquefaciens (limonene, nonan-2-ol, phenethyl alcohol, heptan-2-one and tridecan-2-one) and for F. oxysporum (propan-1-ol, propan-2-ol, heptan-2-one and tridecan-2-one). The amounts of volatile chemical compounds found in B. amyloliquefaciens or in the bacterium–fungus interaction can be used for further research to limit the pathogenic fungus. In the future, one should focus on the compounds that were found exclusively in interactions and whose content was higher than in isolated bacteria. In order to conquer an ecological niche, bacteria increase the production of secondary metabolites, including specific chemical compounds. The results presented are a prerequisite for creating an alternative solution or supplementing the currently used methods of plant protection against F. oxysporum. Understanding and applying the volatile organic compounds produced by bacteria can complement chemical plant protection against the pathogen, especially in greenhouses or tunnels where plants grow in conditions that favour fungal growth. Full article

Endophytic bacteria inhabit plant tissues without damaging them and have specialized adaptation capabilities that allow them to establish themselves in this ecological niche. Endophytes produce numerous secondary metabolites with antimicrobial, anticancer, and pesticide properties, among others. In this study, endophytic bacteria were isolated and characterized from cocoa plants in a Brazilian municipality, with the view to evaluate their potential antagonistic activity on clinical bacterial strains. The isolates were identified through phenotypic analysis and molecular characterization. After bacterial isolation, it was possible to verify the presence of 11 different endophytic strains, with a bacterial load of up to 6.3 × 10³ CFU/g in each plant. The morphological and biochemical profile of the isolates varied. At the taxonomic level, these bacteria showed 99% similarity with the genera Microbacterium, Curtobacterium, Pseudomonas, Bacillus, Ralstonia, and Methylobacterium. The strains of the phylum Actinobacteria, which are known for producing natural bioactive compounds with high biotechnological potential, were effective in inhibiting Staphylococcus aureus ATCC and multidrug-resistant clinical strains. This work aims to expand knowledge about endophytes, with the aim of applying them in other sectors, such as the production of compounds against resistant human pathogens. Full article

The plant microbiome plays a crucial role in the health of the tea plant, while Bacillus thuringiensis (Bt) is widely utilized as a biological pesticide in tea gardens, promoting sustainable agricultural practices. However, the effects of Bt spraying on tea quality and the structure and function of the phyllosphere microbiome remain unclear. This study evaluated the effects of Bt spraying on tea quality, microbiome composition, diversity, and potential functions using tea leaf quality measurements and high-throughput sequencing of the 16S/ITS rDNA genes. Results showed that spraying Bt1 significantly increased the contents of free amino acids (by 15.27%), flavonoids (by 18.00%), soluble sugars (by 62.55%), and key compounds such as epicatechin gallate (by 10.50%), gallocatechin gallate (by 122.52%), and epigallocatechin gallate (by 61.29%), leading to improved leaf quality. Co-occurrence network analysis indicated that the community structure of both epiphytic and endophytic microbes became more complex after Bt treatment. The abundance of beneficial bacteria, such as Novosphingobium, Methylobacterium, and Sphingomonas, increased significantly, while pathogenic fungi like Aspergillus and Phyllosticta decreased. Functional prediction indicated enhanced amino acid metabolism, secondary metabolism, and carbohydrate metabolism, particularly the biosynthesis of flavonoids, which supports disease resistance and boosts secondary metabolite levels. Furthermore, Bt application reduced pathogenic fungi, enhancing the tea plant’s resistance to diseases. Overall, foliar spraying of Bt can positively alter the phyllosphere microbiome by enriching beneficial bacteria and improving metabolic functions, ultimately enhancing tea plant resistance and quality, and providing a scientific basis for sustainable pest management in tea cultivation. Full article

The widespread application of pesticides in agriculture has raised increasing concerns regarding their ecological impact, particularly in aquatic environments. Among these, α-cypermethrin, a highly active isomeric form of cypermethrin, has been extensively used due to its potent insecticidal efficacy and low mammalian toxicity. However, its toxicity to non-target aquatic organisms remains insufficiently understood at the metabolic level. In this study, a targeted metabolomics approach was employed to investigate the biochemical effects of α-cypermethrin in adult zebrafish. Acute toxicity was first determined to establish sublethal exposure concentrations (0.15 µg/L and 1.5 µg/L), followed by a 48 h exposure under a controlled flow-through system. GC-MS/MS-based analysis quantified 395 metabolites, and multivariate statistical models (principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA)) revealed clear dose-dependent metabolic alterations at two time points. Pathway analysis identified disruptions in glycolysis, glycerolipid metabolism, amino acid turnover, and glutathione pathways. Notably, glutamate depletion and associated reductions in GABA (4-Aminobutanoate) and TCA (Tricarboxylic acid) cycle intermediates suggest oxidative stress-induced metabolic bottlenecks. These results provide mechanistic insights into α-cypermethrin-induced toxicity and demonstrate the utility of metabolite-level biomarkers for environmental monitoring. This study contributes to a systems-level understanding of how sublethal pesticide exposure affects vertebrate metabolism, offering a basis for improved ecological risk assessment and pesticide regulation. Full article

Trichoderma spp., Metarhizium spp., and Bacillus spp. are commonly used as biocontrol microorganisms domestically and internationally. However, microbial pesticides currently prepared from single living microorganisms have problems such as a short shelf life, particularly under stressful environment conditions. Secondary metabolites produced from biocontrol microorganisms are comparatively stable when used under field conditions. This study screened the optimal combination of biocontrol metabolites, referred to as TMB, composed of culture filtrates from certain isolates of Trichoderma asperellum 10264, Bacillus subtilis S4-4-10, and Metarhizium anisopliae 3.11962 (1:4:1 (v/v)). RNA-seq analysis and transmission electron microscope observations were carried out to identify the major functions of the most effective culture filtrates against Magnaporthe oryzae (the pathogen causing rice blast disease) and Chilo suppressalis (an insect pest in rice cultivation). TMB was found to disrupt the midgut subcellular structure of C. suppressalis larvae and inhibit the expression of genes related to immunity, membrane components, protein synthesis, and other functions in C. suppressalis larvae and M. oryzae, thereby interfering with their normal growth, reproduction, and infection potential in rice. In addition, TMB was also able to promote rice growth and trigger host defense responses against infections by the target pests and pathogens. In summary, TMB generated different inhibitory activities against multiple targets in C. suppressalis and M. oryzae and induced plant immunity in rice. Therefore, it can be used as a new environmentally friendly agent or alternative to control rice pests and diseases. Full article

With the sustainable increase in agricultural productivity, the need for safer, environmentally friendly pesticide alternatives is also growing. Metabolites of microorganisms (bacteria, fungi, actinomycetes) are emerging as potential bioactive compounds for integrated pest and disease management. These compounds comprise amino acids, carbohydrates, lipids, organic acids, phenolics, peptides, alkaloids, polyketides, and volatile organic compounds. The majority of them have insecticidal, fungicidal, and nematicidal activities. In this review, the classifications, biosynthetic pathways, and ecological functions of primary and secondary metabolites produced by microorganisms are discussed, including their mechanisms of action, ranging from competition to systemic acquired resistance in host plants. The article highlights the importance of microbial genera (viz., Bacillus sp., Pseudomonas sp., Trichoderma sp., Streptomyces sp., etc.) in making chemicals and biopesticides for crop defense. We present the possible applications of microbial biosynthesis strategies and synthetic biology tools in bioprocess development, covering recent innovations in formulation, delivery, and pathway engineering to enhance metabolite production. This review emphasizes the significance of microbial metabolites in improving the plant immunity, yield performance, reduction in pesticide application, and the sustainability of an ecological, sustainable, and resilient agricultural system. Full article

The wine industry aims to reduce pesticide use by utilizing disease-resistant grape varieties, although their oenological potential remains underexplored. This study aimed to evaluate their oenological potential compared to traditional ones. Musts from resistant (Souvignier Gris, Sauvignac, Voltis, and Floreal) and traditional (Chardonnay, Sauvignon Blanc, and Viognier) varieties were fermented at laboratory scale with online CO₂ monitoring, and two yeasts were used to study varietal responses to yeast impact. Wines were analyzed for metabolites from central carbon metabolism, aromas (varietal thiols, ethyl esters, acetate esters, and higher alcohols), and phenolic compounds (hydroxybenzoic acids, hydroxycinnamic acids, flavan-3-ols, and flavonols) using (U)HPLC methods. Principal component analysis (PCA) of all variables revealed Souvignier Gris grouped with a Sauvignon Blanc sample, partially due to varietal thiols. PCA of aromas (PC1: 37.7%, PC2: 17.8%) showed that Souvignier Gris and Sauvignac exhibited similar behavior to Sauvignon Blanc. The heat map of 19 phenolics showed Sauvignac and Sauvignon Blanc clustered, with lower phenolic abundance. This preliminary work contributes to a detailed characterization of the oenological potential of these new varieties and constitutes an essential step in identifying which traditional and well-known varieties they resemble. This will then enable the recommendation of cellar itineraries adapted to their profile. Full article

Organophosphorus (OP) pesticides are a class of chemicals that are extensively used worldwide. The exposure to and use of organophosphates can be assessed by analyzing their metabolites and degradation products, such as dialkyl phosphate (DAP), dialkyl thiophosphate (DATP), and dialkyl dithiophosphate (DADTP). However, since these metabolites/hydrolysis products can result from the metabolism or breakdown of several organophosphorus pesticide families, they serve as nonspecific biomarkers and do not indicate the specific pesticide involved in exposure. In an earlier study, chemical derivatization using N-(2-(bromomethyl)benzyl)-N,N-diethylethanaminium bromide (CAX-B) was described to improve the signal intensity of numerous organophosphorus (OP) acids in liquid chromatography tandem mass spectrometry (LC-ESI-MS/MS) analysis. In the present study, CAX-B was employed to derivatize a set of seven phenolic compounds corresponding to the complementary portion of OP pesticides. The derivatization process using CAX-B was performed in acetonitrile with potassium carbonate at 50 °C for 30 min. LC-Orbitrap-ESI-MS/MS was used to analyze the resulting phenol derivatives and their fragmentation patterns were studied. Notably, the derivatized phenols were markedly more sensitive than the underivatized phenols when LC-ESI-MS/MS was used in MRM technique, without being affected by the sample matrix (soil or plant extracts). This derivatization technique aids in identifying OP pesticides, offers insights into their subfamily, and pinpoints a specific compound through the analysis of corresponding phenol derivative. Full article

Background: The toxicity of pesticides for fish in general and Rainbow Trout (Oncorhynchus mykiss) in particular is an important ecological indicator required by regulations, and it implies the use of a large number of fish. The number of animals needed would be even higher to evaluate metabolites and pesticide impurities. Considering ethical issues, the costs, and the necessary resources, the use of in silico models is often proposed. Aim of the study: We explore the use of advanced Monte Carlo methods to obtain improved results for models testing Rainbow Trout (Oncorhynchus mykiss) acute toxicity. Several versions of the stochastic Monte Carlo simulation of pesticide toxicity for Rainbow Trout, carried out using CORAL software, were studied. The set of substances was split into four subsets: active training, passive training, calibration, and validation. Modeling was repeated five times to enable better statistical evaluation. To improve the predictive potential of models, the index of ideality of correlation (IIC), correlation intensity index (CII), and coefficient of conformism of correlation prediction (CCCP) were applied. Main results and novelty: The most suitable results were observed in the case of the CCCP-based optimization for SMILES-based descriptors, achieving an R² of 0.88 on the validation set, in all five random splits, demonstrating consistent and robust modeling performance. The relationship of information systems related to QSAR simulation and new ideas is discussed, assigning a key role to fundamental concepts like mass and energy. The study of the mentioned criteria of predictive potential during the conducted computer experiments showed that even though they are all aimed at improving the predictive potential, their values do not correlate, except for the CII and the CCCP. This means that, in general, the information impact of the considered criteria has a different nature, at least in the case of the simulation of toxicity for Rainbow Trout (Oncorhynchus mykiss). The applicability domain of the model is specific for pesticides; the software identifies potential outliers by looking at rare molecular fragments. Full article

Phelipanche aegyptiaca is an obligate root-parasitic weed that parasitizes crop roots, threatening the safety of agricultural production. However, the molecular mechanisms underlying the formation of P. aegyptiaca haustorium remain largely unclear. Here, we employed transcriptomics to investigate the molecular events in P. aegyptiaca haustorium formation induced by indole-3-acetic acid. Our study revealed that during P. aegyptiaca haustorium formation, the cell proliferation activity at the tip of the radicle was highest during the young stage and then gradually declined. The differentially expressed genes upregulated during haustorium formation were mainly enriched in DNA replication and plant hormone signal transduction, while those that were downregulated were enriched in biosynthesis of secondary metabolites. Additionally, interfering with the auxin signal weakened the parasitic ability of P. aegyptiaca. These findings enhance our understanding of the mechanism of P. aegyptiaca haustorium formation and contribute to the targeted development of new pesticides for inhibiting P. aegyptiaca. Full article

Fungal phytopathogens employ effector proteins and secondary metabolites to subvert host immunity. Effector proteins have attracted widespread interest in infection, especially for unknown, unreported genes. However, the type of protein remains much less explored. Here, we combined transcriptome analysis and functional validation to identify virulence-associated genes in Fusarium graminearum during fungi infection. A unique secreted protein, FGSE02, was significantly upregulated in the early infection stage. Proteomic characterization revealed that the protein contains a functional signal peptide but lacks known domains. The transient expression of FGSE02 in Nicotiana benthamiana induced rapid cell death, while gene knockout stains reduced fungal virulence without affecting growth. Our findings highlight FGSE02 as a key virulence factor, offering potential targets for disease control. Taken together, the results of this study identify a pathogenic factor and provide new insights into the development of green pesticides. Full article

Despite the fact that organochlorine pesticides (OCPs) were banned many years ago, their residues are still present in the natural environment and pose a potential health risk to humans and animals. This study was undertaken to evaluate the effect of meat and bone meal (1.0, 2.0 and 3.0 t ha⁻¹ MBM) derived from animal by-products and used as fertilizer on the content of γ-HCH (γ-hexachlorocyclohexane), DDT (1,1,1-Trichloro-bis-2,2 [4-chlorophenyl]-ethane) and its metabolites (DDD, dichlorodiphenyldichloroethane and DDE, dichlorodiphenyldichloroethylene) in MBM, soil, and maize grain. A long-term small-area field experiment with MBM applied to maize grown in monoculture was conducted at the Agricultural Experiment Station in Tomaszkowo, Poland (53°71′ N, 20°43′ E) from 2014 to 2017. The concentration of γ-HCH in soil decreased gradually, whereas the levels of DDT and its metabolites continued to increase in successive years of the experiment. A minor increase in DDT accumulation in maize grain was also observed, particularly in treatments supplied with mineral fertilizers. Meat and bone meal affected grain contamination levels, and the highest MBM rates decreased the content of DDT metabolites in grain. The results of the study suggest that MBM could be a secondary source of OCPs in the agricultural environment and that their availability to plants varies depending on soil parameters and weather conditions. Full article

The Farm-to-Fork strategy, an essential component of the European Green Deal, aims to establish a sustainable and healthy food system. A crucial aspect of this strategy is reducing synthetic pesticide use by 50% by 2030. In this context, biocontrol is seen as a vital tool for achieving this goal. However, the upscaling of biocontrol faces several challenges, including technical and socio-economic issues and concerns regarding the legal status of biocontrol products. This article focuses on the Positive List, which includes indigenous and introduced species that have been established for use in EPPO countries and approved biological agents in some OECD countries. This article discusses microbial control agents and active substances derived from microbial metabolites, macro-agents, semi-chemicals, and plant-based compounds. It covers their origins, active substances, mechanisms of action against target pests, application methods, market availability, benefits, and potential environmental side effects. Additionally, it discusses the role of beneficial insects and mites as natural enemies in Integrated Pest Management (IPM) within the context of conservation methods. This article addresses the future of biological control, which largely relies on advancements in science to tackle two critical challenges: enhancing the reliability and effectiveness of biopreparations in field conditions and developing suitable formulations of biopesticides tailored to large-scale cultivation technologies for key crops. Full article