Potential Fungicides Research Articles

Fungal effector genes involved in the suppression of chitin signaling as novel targets for the control of powdery mildew disease via a nontransgenic RNA interference approach.

Chitin is a crucial component of fungal cell walls and an effective elicitor of plant immunity; however, phytopathogenic fungi have developed virulence mechanisms to counteract the activation of this plant defensive response. In this study, the molecular mechanism of chitin-induced suppression through effectors involved in chitin deacetylases (CDAs) and their degradation (EWCAs) was investigated with the idea of developing novel dsRNA-biofungicides to control the cucurbit powdery mildew caused by Podosphaera xanthii. The molecular mechanisms associated with the silencing effect of the PxCDA and PxEWCAs genes were first studied through dsRNA cotyledon infiltration assays, which revealed a ≈80% reduction in fungal biomass and a 50% decrease in gene expression. To assess the impact on powdery mildew disease control, in vitro and in planta assays were carried out in growth chamber and glasshouse experiments, with ≈50% reduction in disease symptoms after 8 days postinoculation (dpi) in leaf discs and 12 dpi in plants' leaves, respectively. This control was extended for 21 days when the dsRNAs were protected on the carbon dot nanocarriers. Additionally, the uptake of the dsRNAs by fungal spores was observed 12 h postapplication via confocal microscopy, and efficient processing of dsRNAs into siRNAs by the melon RNAi machinery was observed 24 h postspraying through sRNA-seq. This study highlights notable advancements in environmentally friendly disease management, and features the technological potential of RNA-based fungicides together with nanotechnology for cucurbit powdery mildew control. © 2025 Society of Chemical Industry.

The 24-kDa subunit of mitochondrial complex I regulates growth, microsclerotia development, stress tolerance, and virulence in Verticillium dahliae

BackgroundThe complete mitochondrial respiratory chain is a precondition for maintaining cellular energy supply, development, and metabolic balance. Due to the evolutionary differentiation of complexes and the semi-autonomy of mitochondria, respiratory chain subunits have become critical targets for crop improvement and fungal control. In fungi, mitochondrial complex I mediates growth and metabolism. However, the role of this complex in the pathogenesis of phytopathogenic fungi is largely unknown.ResultsIn this study, we identified the NADH: ubiquinone oxidoreductase 24-kDa subunit (VdNuo1) of complex in vascular wilt pathogen, Verticillium dahliae, and examined its functional conservation in phytopathogenic fungi. Based on the treatments with respiratory chain inhibitors, the mitochondria-localized VdNuo1 was confirmed to regulate mitochondrial morphogenesis and homeostasis. VdNuo1 was induced during the different developmental stages in V. dahliae, including hyphal growth, conidiation, and melanized microsclerotia development. The VdNuo1 mutants displayed variable sensitivity to stress factors and decreased pathogenicity in multiple hosts, indicating that VdNuo1 is necessary in stress tolerance and full virulence. Comparative transcriptome analysis demonstrated that VdNuo1 mediates global transcriptional effects, including oxidation and reduction processes, fatty acid, sugar, and energy metabolism. These defects are partly attributed to impairments of mitochondrial morphological integrity, complex assembly, and related functions. Its homologue (CgNuo1) functions in the vegetative growth, melanin biosynthesis, and pathogenicity of Colletotrichum gloeosporioides; however, CgNuo1 does not restore the VdNuo1 mutant to normal phenotypes.ConclusionsOur results revealed that VdNuo1 plays important roles in growth, metabolism, microsclerotia development, stress tolerance, and virulence of V. dahliae, sharing novel insight into the function of complex I and a potential fungicide target for pathogenic fungi.

Synthesis and anti-fungi/oomycetes activity of cuminic acid derivatives containing thiourea group for crop protection.

In search of novel natural product-based fungicides,twenty-four cuminic acid derivatives containing thiourea group were synthesized and characterized by 1H-NMR, 13C-NMR and HRMS spectra. The anti-fungi/oomycete activity bioassay showed that the some of the title compounds displayed moderate to good anti-fungi activity against Botryosphaeria dothidea (B. dothidea), Sclerotinia sclerotiorum (S. sclerotiorum) and Valsa mali (V. mali). Compound 4k exhibited the best in vitro anti-fungi activity toward V. mali. The in vivo experiment identified that 4k possessed considerable anti-V. mali protective and curative effect at 200 mg/L. Antifungal mechanism study showed that 4k could destroy morphology of V. mali mycelia, increase the cell membrane permeability, inhibit the dry weight of V. mali mycelia and led to the increase of reactive oxygen species(ROS) level. The phytotoxicity experiment revealed that compound 4k showed good safety on mung bean. This cuminic acid derivatives would be potential fungicide for controlling apple canker disease.

Synthesis and Antifungal Activity of 5-Trifluoromethyl-1,2,4-oxadiazole derivatives Containing Hydrazide Group as Potential Fungicides

To further investigate the potential fungicide with heterocyclic moiety, three new 5-trifluoromethyl-1,2,4- oxadiazole derivatives derivatives containing hydrazide group were designed, synthesized, and assayed for inhibitory activity against plant pathogenic fungi. Especially, compound 3a presented excellent in vitro antifungal activity against Valsa mali and Botryosphaeria dothidea, which was substantially stronger than chlorothalonil. In vivo antifungal assay revealed that compounds 3a and 3b exhibited prominent protective activity against soybean rust, which were at the same level with benzovindiflupyr. These results indicated that 5-trifluoromethyl-1,2,4-oxadiazole derivatives could be a potential fungicide lead.. KEYWORDS :5-trifluoromethyl-1,2,4-oxadiazole derivatives, Antifungal activity, Hydrazide.

Genomic Insights into the Bactericidal and Fungicidal Potential of Bacillus mycoides b12.3 Isolated in the Soil of Olkhon Island in Lake Baikal, Russia.

The dispersal of plant pathogens is a threat to the global economy and food industry which necessitates the need to discover efficient biocontrol agents such as bacteria, fungi, etc., inhibiting them. Here, we describe the Bacillus mycoides strain b12.3 isolated from the soil of Olkhon Island in Lake Baikal, Russia. By applying the co-cultivation technique, we found that the strain inhibits the growth of plant pathogens, such as the bacteria Xanthomonas campestris, Clavibacter michiganensis, and Pectobacterium atrospecticum, as well as the fungus Alternaria solani. To elucidate the genomic fundament explaining these activities, we leveraged next-generation whole-genome sequencing and obtained a high-quality assembly based on short reads. The isolate bore seven known BGCs (biosynthetic gene clusters), including those responsible for producing bacillibactin, fengycin, and petrobactin. Moreover, the genome contained insecticidal genes encoding for App4Aa1, Tpp78Ba1, and Spp1Aa1 toxins, thus implicating possible pesticidal potential. We compared the genome with the 50 closest assemblies and found that b12.3 is enriched with BGCs. The genomic analysis also revealed that genomic architecture corresponds to the experimentally observed activity spectrum implying that the combination of produced secondary metabolites delineates the range of inhibited phytopathogens Therefore, this study deepens our knowledge of the biology and ecology of B. mycoides residing in the Lake Baikal region.

Synthesis and Fungicidal Activity Evaluation of Novel Triazole Thione/Thioether Derivatives Containing a Pyridylpyrazole Moiety.

Compounds containing N-pyridylpyrazole motif have aroused interest and brought about research hotspots due to their highly-efficient insecticidal activity. The fungicidal potential of N-pyridylpyrazole derivatives has gradually been disclosed in recent years. To discover new agrochemicals with poly-heterocyclic features, a series of novel triazole thione/thioether derivatives containing pyridylpyrazole motif (8-11) was synthesized. The new compounds were identified by melting point, 1H-NMR, 13C NMR, 19F NMR, HRMS, and elemental analysis. The bioassays showed that most of the pyridylpyrazole-containing triazole thione Mannich bases possessed favorable in vitro fungicidal activity toward pathogenic fungi, such as Magnaporthe oryzae, Sclerotinia sclerotiorum, Botrytis cinerea and Fusarium verticillioides, and were comparable with those of the contrast compounds A and triadimefon. Some of them exhibited moderate to good in vivo fungicidal activity against S. sclerotiorum at 0.2 mg/mL (e. g. 8f control efficacy: 60.9±3.2 %). The SEM observation displayed that 8f might cause disruption of cell membrane and wall of S. sclerotiorum. Compounds 8a, 8c, 8f-8h, 8p and 9b can serve as promising new fungicidal agents to make further structural optimization. The findings in this article provide useful clue and guidance for the design and development of new poly-heterocyclic agrochemicals.

Ammonium Dinitramide as a Prospective N-NO2 Synthon: Electrochemical Synthesis of Nitro-NNO-Azoxy Compounds from Nitrosoarenes.

In this study, the electrochemical coupling of nitrosoarenes with ammonium dinitramide is discovered, leading to the facile construction of the nitro-NNO-azoxy group, which represents an important motif in the design of energetic materials. Compared to known approaches to nitro-NNO-azoxy compounds involving two chemical steps (formation of azoxy group containing a leaving group and its nitration) and demanding expensive, corrosive, and hygroscopic nitronium salts, the presented electrochemical method consists of a single step and is based solely on nitrosoarenes and ammonium dinitramide. The dinitramide salt plays the roles of both the electrolyte and reactant for the coupling. Despite the fact that many side reactions can be expected due to the redox-activity of both the reagents and target products, under optimized conditions the synthesis is performed in an undivided cell under constant current conditions with high current density and can be easily scaled up without a reduction in the product yield. Moreover, the synthesized nitro-NNO-azoxy compounds are discovered to be potent fungicides active against a broad range of phytopathogenic fungi.

L-Isoleucine-Derived Amide-hydrazide Compounds Evaluated as a Novel Potential Agricultural Fungicide.

Building upon previous structure-activity relationships about the fungicidal amide and hydrazide lead structures, 24 novel amide-hydrazide compounds were designed and synthesized with L-isoleucine as the initial skeleton to explore the impact of substituents in the hydrazide bridge on the fungicidal activity. Among these compounds, A5 exhibited excellent and broad spectrum inhibitory activity, along with satisfactory in vivo protective efficiency against R. solani at concentrations of 200 and 50 μg·mL-1. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations revealed that compound A5 induced significant morphological changes in the R. solani mycelium coupled with vacuole rupture and cytoplasmic inhomogeneity in cellular structures. Transcriptomic and metabolomic analyses indicated that, following A5 treatment, the differentially expressed genes and metabolites were significantly enriched in carbohydrate metabolism-related pathways as well as in lipid metabolism-associated pathways, including glycerophospholipid metabolism, steroid biosynthesis, arachidonic acid metabolism, and sphingolipid metabolism. Additionally, compound A5 demonstrated low toxicity to zebrafish, with survival rates of 100% and 60% at concentrations of 1 and 10 μg·mL-1, respectively, over a period of 7 days. The above results provide theoretical guidance for the development of novel green hydrazide fungicidal candidates.

Lac-based-biosynthesis of zinc–copper mixed metal oxide nanoparticles and evaluation of their antifungal activity against A.alternata and F. oxysporum

The use of animal-based sources for biosynthesis resonates with the growing market for sustainable and eco-friendly materials, but remains severely unexplored in comparison to plant-based and microbial sources. In this purview, shellac, a bioresin obtained from the Kerria lacca insect, is emerging as an ideal candidate for nanomaterial fabrication due to its abundant availability and anti-microbial properties. It is commonly available in the form of raw seed lac, (SL) and in the processed button lac (BL) form. Therefore, in the current study, the potential of shellac as a green agent for the synthesis of zinc-copper mixed metal oxide nanoparticles, and the anti-fungal activitiy of synthesized nanoparticles was investigated. Two types of zinc copper oxide nanoparticles were synthesized using button lac (ZnCu(BL)O) and seed lac (ZnCu(SL)O), and they were characterised using various techniques such as Powder X-Ray Diffraction (PXRD), Fourier Transform Infrared spectroscopy (FTIR) and Scanning Electron Microscopy-Energy Dispersive X-Ray (SEM-EDX) spectroscopy. PXRD pattern confirmed the hexagonal wurtzite structure of crystalline ZnCuO NPs. FTIR analysis elucidated the presence of functional groups that were potentially involved in the synthesis of MMO nanoparticles, and the formation of Zn–O and Cu–O bonds was suggested by appearance of bands at 559 cm−1 and 555 cm−1. The morphology and elemental composition of the MMONPs were examined using SEM-EDX techniques that revealed the formation of biosynthesized ZnCuO NPs as spherical agglomerates having uniform distribution of Zn, Cu, C and O throughout the material. Further, the antifungal activity of synthesized NPs was evaluated against F. oxysporum and A. alternata fungal pathogens. It was found that the biosynthesized nanoparticles exhibited significant fungicidal potential against both F. oxysporum and A. alternata. Furthermore, the antifungal results indicated that ZnCuSL-(O) NPs exhibited higher antifungal activity against both fungal strains than ZnCuBL-(O) NPs and chemically synthesized ZnCu-O NPs. Thus, ZnCuSL-(O) NPs and ZnCuBL-(O) NPs prepared using shellac may be considered as cost-effective and eco-friendly substitutes over traditional fungicides.

Antifungal Activity of Novel Isoindoline-2-Yl Putrescines as Potential Autophagy-Activated Fungicide.

The exacerbation of plant fungal diseases necessitates the development of new fungicides to prevent outbreaks. In this study, five novel isoindoline-2-yl putrescines (ISPs) were synthesized, and their synthetic procedures and gram-scale preparation were explored. When tested at 50 μg mL-1, ISPs did not significantly inhibit mycelial growth on agar plates. However, at 100 μg mL-1, they demonstrated remarkable in vivo efficacy in mitigating Botrytis cinerea infection, especially ISP3 showed curative and protective activities of 91.9 % and 92.6 %, respectively. Moreover, ISP3 also effectively halted lesion expansion of gray mold, Sclerotic rot, and Fusarium scabs, while inducing excessive malformed top mycelial branches of B. cinerea and Sclerotinia sclerotiorum, suppressing sclerotia formation in S. sclerotiorum, and triggering autophagic vacuolization with numerous autophagosomes in the mycelia of these fungi. Molecular docking revealed that ISP3 effectively bound to the active site of BcAtg3, forming hydrogen bonds with Ser279, Gly343, Asp370, and Asp13, along with establishing a stable salt bridge with Asp13. Furthermore, ISP3 possessed favorable ADMET properties. These findings highlight ISP3 as a promising antifungal candidate through autophagy activation.

Pathogen Composition and Fungicide Sensitivity in Rice Spikelet Rot Disease.

Rice spikelet rot disease (RSRD) is an emerging threat to rice crops, with sporadic but severe outbreaks in China in recent years. The composition of its pathogenic fungi has not been consistently identified, and chemical control methods remain unclear. This study aims to characterize the pathogen species responsible for RSRD and develop effective control strategies. Regional variations in disease symptoms and pathogen compositions were analyzed, which led to the identification of six novel pathogens, including Fusarium tanahbumbuense, Alternaria gaisen, Curvularia verruculosa, Curvularia brachyspora, Curvularia muehlenbeckiae, and Curvularia hominis. The pathogenic composition of RSRD exhibited considerable variation across different latitudes within China. Specifically, Alternaria spp. predominated in the Heilongjiang and Liaoning Provinces. Whereas Fusarium spp. and Curvularia spp. were more prevalent in the Hainan and Fujian Provinces. In contrast, Fusarium spp. and Alternaria spp. were the dominant pathogens in the Anhui and Jiangsu Provinces. Furthermore, an assessment of the sensitivity of these predominant pathogens to four chemical compounds was conducted, which led to the identification of potential fungicides for effective disease control. This research provides valuable insights into the pathogenic profile of RSRD across different regions and offers strategic recommendations for fungicide-based management of the disease.

Synthesis, Spectroscopy and Biological Studies of Copper and Silver Complexes Derived from 2-Substituted Amino Propanoic Acid

Synthesis of copper and silver complexes were prepared from novel Schiff base ligand. These synthesized ligand and their metal complexes were characterized by elemental analysis, FT-IR, 1H NMR, UV-Vis and Mass spectrometry. The coordination of amino nitrogen, phenolic oxygen, and carboxylato oxygen atoms is shown by the infrared spectra.The Schiff bases and its complexes were screened for their in vitro antibacterial and antifungal studies against the bacteria Pseudomonas Aeruginosa (PA, Gram -ve), Bacillus Cirroflagellosus (BC, Gram +ve), Penicillium Notatium (PN) and Aspergillus Niger (AN) strains. The results of the antibacterial investigation show that the copper and silver complexes possess more potent bactericide and fungicide properties than the ligand.

In silico modeling and experimental validation of 2-oxoimidazolidin-4-sulfonamides as low-toxicity fungicides against Phytophthora infestans

Phytophthora infestans control is a long-standing problem that has caused ongoing difficulties and brought limited success for over a century. Traditional methods, such as fungicides, have drawbacks including high cost, restrictions on organic farming, potential risks to the environment and human health, and the development of resistant strains. In this study, we employed cutting-edge computer-based techniques, including Quantitative Structure-Activity Relationship (QSAR) modeling and molecular docking simulations, to uncover new fungicidal compounds and gain insights into their specific mechanisms of action against P. infestans. QSAR modeling on the number of compounds tested as P. infestans inhibitors was performed using an interactive OCHEM web platform. The predictive ability of the developed classification models had a balanced accuracy (BA) of 77–85 % for the training set and BA = 89–93 % for the validation external test set. During the in vitro testing against P. infestans, thirteen synthesized 2-oxoimidazolidine-4-sulfonamides demonstrated inhibition rates, ranging from 23.6 % to 87.4 %. The fungicidal potential of six of these fungicides ranged from 79.3 % to 87.4 %, which is comparable to the activity of known fungicides. Acute toxicity results using the well-known aquatic marker Daphnia magna showed that the most active sulfonamides 3d, 3f, 3h, 3j, 3k, and 3l, with LC50 values ranging from 13.7 to 52.9 mg/L, are low-toxicity compounds. The molecular docking results demonstrated a potential mechanism of the antifungal action of the studied 2-oxoimidazolidin-4-sulfonamide derivatives via the inhibition of fungal CYP51, a sterol biosynthesis enzyme.

Synthesis and Antifungal Evaluation of Cinnamic Acid-Geraniol Hybrids as Potential Fungicides.

Cinnamic acid and geraniol are two well-known antifungal natural products and widely applied in food and cosmetics industries. To discover novel natural product-based fungicide candidates with more potent activity and good ecological compatibility for the management of plant diseases, a series of cinnamic acid-geraniol hybrids were prepared by means of molecular hybridization and their chemical structures were well confirmed by spectral analysis. The antifungal activities of the target compounds against three phytopathogenic fungi Fusarium graminearum, Gaeumannomyces graminis (Sacc.) Arx et Oliver var. tritici (Sacc.) Walker, and Valsa mali were evaluated. Among them, compounds 5 e and 5 f showed the remarkable antifungal activity against G. graminis with the EC50 values of 82.719 and 91.828 μg/mL, respectively; while compounds 5 f and 6 b exhibited the obvious antifungal activity against V. mali. It suggested that compound 5 f can be further optimized for the design of novel broad-spectrum fungicide molecules as the secondary lead compound. In addition, some interesting structure-antifungal activity relationships were obtained. This work will provide some reference and guidance for the further discovery of novel fungicide candidates based on cinnamic acid and geraniol.

New binary mixtures of fungicides against Macrophomina phaseolina: Machine learning-driven QSAR, read-across prediction, and molecular dynamics simulation

Quantitative Structure-Activity Relationship (QSAR) analysis greatly enhances the development and research of pesticides. This study employed Multiple Linear Regression (MLR), machine learning (ML), and read-across (RA) approaches to investigate the combined effects of binary mixtures of fungicides on Macrophomina phaseolina. Using the Fixed Ratio Ray Design (FRRD) method, 75 binary mixtures of six frequently used fungicides were generated, with many exhibiting additive interactions as indicated by the Concentration Addition (CA) and Independent Action (IA) models. The QSAR analysis revealed that Support Vector Regression (SVR) and Gaussian Process Regression (GPR) models were the most effective, outperforming the Least Squares Kernel (LSK), MLR, and RA methods. SVR achieved an outstanding R2 of 0.95 and Q2LMO of 0.81, whereas GPR demonstrated values of 0.93 and 0.81 for the same metrics. Internal and external validation confirmed the reliability and generalizability of these models, suggesting they could be applied to a wider array of data. Moreover, Molecular Dynamics (MD) simulations showed that the effects of the fungicides are linked to physiological mechanisms rather than intermolecular interactions within their formulations. This study establishes a robust framework for creating potent fungicide combinations that improve disease management efficacy while promoting environmental sustainability and reducing the chemical load to mitigate negative impacts.

Antimicrobial activities of modified and unmodified pectin obtained from peels of Irvingia gabonensis, Cola milleni, and Theobroma cacao on specific pathogenic organisms

The antibacterial and antifungal activities of ethanolic extracts of pectin derived from the peels of Theobroma cacao, Cola milleni, and Irvingia gabonensis were investigated against phytopathogenic bacteria and fungi. The agar diffusion method was employed to test the extracts against Staphylococus aureus, Pseudomonas aeroginosa, Chromobacterium violaceum, Streptococcus feacalis, Xanthomonas axonopodis, Erwinia carotovora, Sclerotium rulfsii, Pythophthora palmivora, and Pyricularia oryzae. Significant differences (p<0.05) were observed in all control groups. The extracts inoculated with Streptomycin exhibited the highest activity against all bacterial strains. Conversely, the unmodified extracts of pectin samples from cola, cocoa, and wild mango displayed the least inhibitory activity against the tested bacterial strains, while the modified extracts with Chloro Acetic Acid (CAA), Para Amino Benzoic Acid (PABA), and Para Nitro Benzoic Acid (PNBA) showed varying inhibitory effects. The control sample inoculated with Mancozeb demonstrated the highest zone of inhibition against all fungal strains in the three pectin samples. However, the modified pectin samples exhibited increased inhibitory effects compared to the unmodified pectin extract, although the results were closer to the control. The higher values of modified pectin can be attributed to the presence of modifying agents such as long-chain hydrocarbons, acetic acid, chloro compounds, carboxyl, benzene rings, amino groups, and nitro groups. The presence of secondary metabolites in the pectin samples may also contribute to the higher values observed in both modified and unmodified samples. Overall, the results indicate the fungicidal and bactericidal potential of the extracts against the tested organisms, suggesting their potential use as broad-spectrum antimicrobial agents.

Toxicity potential of a pyraclostrobin-based fungicide in plant and green microalgae models

ABSTRACT Pyraclostrobin-based fungicides play an effective role in controlling fungal diseases and are extensively used in agriculture. However, there is concern regarding the potential adverse effects attributed to exposure to these fungicides on non-target organisms and consequent influence exerted on ecosystem functioning. Thus, it is essential to conduct studies with model organisms to determine the impacts of these fungicides on different groups of living organisms. The aim of this study was to examine the ecotoxicity associated with exposure to commercial fungicides containing pyraclostrobin. The focus of the analysis involved germination and initial development of seedlings of 4 plant models (Lactuca sativa, Raphanus sativus, Pennisetum glaucum and Triticum aestivum), in addition to determining the population growth rate and total carbohydrate content in microalga Raphidocelis subcapitata. The fungicide pyraclostrobin adversely influenced growth and development of the tested plants, indicating a toxic effect. The fungicide exerted a significant impact on the initial development of seedlings of all model species examined with T. aestivum plants displaying the greatest susceptibility to pyraclostrobin. Plants of this species exhibited inhibitory effects on both aerial parts and roots when treated with a concentration of 4.75 mg/L pyraclostrobin. In addition, the green microalga R. subcapitata was also significantly affected by the fungicide, especially at relatively high concentrations as evidenced by a reduction in total carbohydrate content. This commercial fungicide demonstrated potential phytotoxicity for the tested plant models and was also considered toxic to the selected microalgae, indicating an ecotoxic effect that might affect other organisms in aquatic environments.

Novel Essential Oil-Based Thiosemicarbazone Compounds as Potential Fungicides in Controlling Postharvest Diseases of Citrus Fruit.

To develop novel fungicides for controlling postharvest fungal diseases in citrus fruits, 12 essential oil (EO)-based thiosemicarbazones compounds, termed hydrazine-carbothioamide, were prepared according to the condensation method. In vitro assays showed that compound 13j exhibited the strongest antifungal activity (minimum inhibitory concentration [MIC] = minimum fungicidal concentration [MFC] = 0.0125 mg/mL) against Penicillium digitatum. An in vivo study revealed that 5 × MFC of compound 13j can effectively mitigate the green mold incidence of citrus fruit inoculated with P. digitatum, as well as fruit rot during natural storage, at a level comparable to that of the chemical fungicide prochloraz. Throughout this process, fruit quality was maintained. The hemolysis assay showed that these thiosemicarbazone compounds have good biocompatibility and that their safety is comparable to that of prochloraz. The antifungal activity of compound 13j was attributed to membrane damage, as confirmed using scanning electron microscopy (SEM), Calcofluor white (CFW) staining, propidium iodide (PI) staining, Fourier transform-infrared (FT-IR) spectroscopy, optical density (OD)260, and relative conductivity assays. Collectively, our results indicate that compound 13j can be used as an antifungal agent to control the postharvest decay of citrus fruits.

Colchicine, Caffeine, Gramine, and Their Derivatives as Potential Herbicides, Fungicides, and Insecticides.

A preliminary in silico screening of 94 compounds, including colchicine, caffeine, gramine, and their derivatives, was conducted to identify potential herbicides, insecticides, and fungicides. Among the compounds tested, only gramine and its 13 derivatives exhibited potential activity. These compounds were further tested against eight species of insects, three species of weeds, and four species of fungi. All of the tested alkaloids were found to be ineffective as herbicides and insecticides, but they did exhibit some fungicidal activity. Four gramine derivatives showed some activity against Phytophthora infestans, Botrytis cinerea, Zymoseptoria tritici, and Fusarium culmorum.

Extraction and chemical constituents of the essential oils from Rosmarinus officinalis L. and Corymbia citriodora

The essential oils of Rosmarinus officinalis L. and Corymbia citriodora (Hook.) K.D.Hill & L.A.S.Johnson leaves have chemical constituents with fungicide potential. The objective of this work was to determine the yield and the main chemical compounds of the essential oils of these species. Plants of the two species were georeferenced and collected in municipalities of Rio Grande do Sul, and identified in the Botany Laboratory of UNIJUÍ. The essential oils were extracted by hydrodistillation and the yield was based on fresh vegetable mass. The analyses of the chemical constituents were determined by CG-MS. A yield of 0.49% was obtained for R. officinalis and of 1.54% for C. citriodora. Similar to other studies, the major constituents of rosemary essential oil were camphor, 1,8-cineol, canfene and α-pineno, and the ones of eucalyptus essential oil were citronelal, isopulegol and citronelol. It is concluded that the chemical constituents are similar to those reported in the literature and the essential oil yield of the species is low and dependent on external conditions.