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Pesticides are widely used to increase agricultural productivity, however, weak adhesion and deposition lead to low efficient utilization. Herein, we prepare a nanopesticide formulation (tebuconazole nanopesticides) which is leaf-adhesive, and water-dispersed via a rapid nanoparticle precipitation method, flash nanoprecipitation, using temperature-responsive copolymers poly-(2-(dimethylamino)ethylmethylacrylate)- b -poly(ε-caprolactone) as the carrier. Compared with commercial suspensions, the encapsulation by the polymer improves the deposition of TEB, and the contact angle on foliage is lowered by 40.0°. Due to the small size and strong van der Waals interactions, the anti-washing efficiency of TEB NPs is increased by 37% in contrast to commercial ones. Finally, the acute toxicity of TEB NPs to zebrafish shows a more than 25-fold reduction as compared to commercial formulation indicating good biocompatibility of the nanopesticides. This work is expected to enhance pesticide droplet deposition and adhesion, maximize the use of pesticides, tackling one of the application challenges of pesticides. Weak adhesion is a common hindrance to efficient utilization of pesticides in agricultural applications. Here, authors demonstrate leaf-adhesive tebuconazole nanopesticides which can be water-dispersed via flash nanoprecipitation using temperature-responsive copolymers PDMAEMA-b-PCL as the carrier.

Tebuconazole (TEB) is a fungicide widely used in vineyards and is a suspected teratogen for humans. The aim of this research was to identify urinary biomarkers and the best sampling time for the biological monitoring of exposure to TEB in agricultural workers. Seven vineyard workers of the Monferrato region, Piedemont, Italy, were investigated for a total of 12 workdays. They treated the vineyards with TEB for 1–2 consecutive days, one of them for 3 days. During each application coveralls, underwears, hand washing liquids and head coverings were used to estimate dermal exposure. For biomonitoring, spot samples of urine from each individual were collected starting from 24 h before the first application, continuing during the application, and again after the application for about 48 h. TEB and its metabolites TEB-OH and TEB-COOH were measured by liquid chromatography/triple quadrupole mass spectrometry. TEB contamination of coveralls and total dermal exposure showed median levels of 6180 and 1020  μ g. Urinary TEB-OH was the most abundant metabolite; its excretion rate peaked within 24 h after product application (post 24 h). In this time frame, median levels of TEB-OH and TEB-COOH ranged from 8.0 to 387.8  μ g/l and from 5.7 to 102.9  μ g/l, respectively, with a ratio between the two metabolites of about 3.5. The total amount of urinary metabolites (U-TEB eq ) post 24 h was significantly correlated with both TEB on coveralls and total dermal exposure (Pearson’s r =0.756 and 0.577). The amount of metabolites excreted in urine represented about 17% of total dermal TEB exposure. Our results suggest that TEB-OH and TEB-COOH in post-exposure urine samples are promising candidates for biomonitoring TEB exposure in agricultural workers.

A polybenzidine-modified Fe 3 O 4 @SiO 2 nanocomposite was successfully synthesized through a chemical oxidation method and employed as a novel sorbent in dispersive magnetic solid phase extraction (DMSPE) for the preconcentration and determination of three triazole fungicides (TFs), namely diniconazole, tebuconazole, and triticonazole in river water, rice paddy soil, and grape samples. The synthesis method involved a polybenzidine self-assembly coating on Fe 3 O 4 @SiO 2 magnetic composite. Characterization techniques such as FT-IR, XRD, FESEM, EDX, and VSM were used to confirm the correctness of the synthesized nano-sorbent. The target TFs were determined in actual samples using the synthesized nanocomposite sorbent in combination with gas chromatography–flame ionization detection (FID). Several variables were carefully optimized , including the sample pH, sorbent dosage, extraction time, ionic strength, and desorption condition (solvent type, volume, and time). Under the optimized experimental conditions, the method exhibited linearity in the concentration range 5–1000 ng mL −1 for triticonazole and 2–1000 ng mL −1 for diniconazole and tebuconazole. The limits of detection (LOD) for the three TFs were in the range 0.6–1.5 ng mL −1 . The method demonstrated acceptable precision with intra-day and inter-day relative standard deviation (RSD) values of less than 6.5%. The enrichment factors ranged from 248 to 254. Finally, the method applicability was evaluated by determining TFs in river water, rice paddy soil, and grape samples with recoveries in the range 90.5–106, indicating that the matrix effect was negligible in the proposed DMSPE procedure. Graphical Abstract

The agricultural triazole fungicide tebuconazole (TCZ) has been implicated in the emergence of azole resistance in human fungal pathogens, but its direct role in selecting resistance and tolerance in Candidozyma auris remains unclear. Here, we investigated whether laboratory exposure of a clade III clinical C. auris isolate to TCZ could induce cross−resistance to clinical antifungals. Among 17 agrochemicals tested, only TCZ exhibited intrinsic antifungal activity. Brief (48 h) exposure to sub-MIC TCZ (1 μg/mL) selected variants (6.9% frequency) with cross-resistance to TCZ and fluconazole, but full susceptibility to caspofungin. Exposure to supra-MIC TCZ (8-32 μg/mL) produced three phenotypic classes: Class 2 (TCZ−R, fluconazole−R) and Class 3 (TCZ−R, fluconazole−R, plus tolerance to caspofungin and micafungin). The frequency of Class 3 increased dose-dependently from 23% to 50% as TCZ concentration rose. RNA-Seq revealed that both classes overexpressed MDR1, TAC1b, UPC2 and FKS1, but Class 2 showed broad ergosterol pathway upregulation, whereas Class 3 exhibited restricted ergosterol activation but downregulation of the sole chitinase gene CHT1 (5.17−fold), a known mechanism of echinocandin tolerance. Unlike the CRS−MIS phenomenon in Candida glabrata, our Class 3 adaptors displayed equal tolerance to both caspofungin and micafungin. Collectively, these findings demonstrate that, in a clade III clinical isolate of C. auris under the tested laboratory conditions, laboratory exposure to an agricultural triazole can rapidly select for clinically relevant azole cross−resistance and echinocandin tolerance in C. auris, suggesting that environmental fungicide use may inadvertently compromise the efficacy of last−line antifungals.

Graphite carbon nitride (g-C 3 N 4 ) is a two-dimensional nano-sheet with electronic properties, which shows unique characteristics with high chemical and thermal stability in its structure. The functionalization of these compounds through covalent bonding is an important step towards significantly improving their properties and capabilities. To achieve this goal, a novel strategy for the covalent functionalization of Fe 3 O 4 @g-C 3 N 4 with thiamine hydrochloride (vitamin B1) via cyanuric chloride (TCT), which is a divalent covalent linker, was presented. The efficiency of Fe 3 O 4 @gC 3 N 4 @Thiamine as a heterogeneous organic catalyst in the synthesis of spirooxindole-pyran derivatives and 2-amino-4 H -pyran under solvent-free conditions was evaluated and the yields of high-purity products were presented. In addition, easy recycling and reuse for seven consecutive cycles without significant reduction in catalytic activity are other features of this catalyst. Moreover, the performance of the prepared sorbent in the microextraction technique (herein, magnetic solid phase extraction) was studied. The tebuconazole was selected as the target analyte. The target analyte was extracted and determined by HPLC–UV. Under the optimum condition, the linear range of the method (LDR) was estimated in the range of 0.2–100 μg L −1 (the coefficient of determination of 0.9962 for tebuconazole). The detection limit (LOD) of the method for tebuconazole was calculated to be 0.05 µg L −1 . The limit of quantification (LOQ) of the method was also estimated to be 0.16 µg L −1 . In order to check the precision of the proposed method, the intra-day and inter-day relative standard deviations (RSD%) were calculated, which were in the range of 1.5- 2.8%. The method was used for the successful extraction and determination of tebuconazole in tomato, cucumber, and carrot samples.

Modern agricultural practices rely on synthetic fungicides to control plant disease, but the application of these fungicides has raised concerns regarding human and environmental health for many years. As a substitute, environmentally friendly fungicides have been increasingly introduced as alternatives to synthetic fungicides. However, the impact of these environmentally friendly fungicides on plant microbiomes has received limited attention. In this study, we used amplicon sequencing to compare the bacterial and fungal microbiomes in the leaves of powdery mildew-infected cucumber after the application of two environmentally friendly fungicides (neutralized phosphorous acid (NPA) and sulfur) and one synthetic fungicide (tebuconazole). The phyllosphere α-diversity of both the bacterial and fungal microbiomes showed no significant differences among the three fungicides. For phyllosphere β-diversity, the bacterial composition exhibited no significant differences among the three fungicides, but fungal composition was altered by the synthetic fungicide tebuconazole. While all three fungicides significantly reduced disease severity and the incidence of powdery mildew, NPA and sulfur had minimal impacts on the phyllosphere fungal microbiome relative to the untreated control. Tebuconazole altered the phyllosphere fungal microbiome by reducing the abundance of fungal OTUs such as Dothideomycetes and Sordariomycetes, which included potentially beneficial endophytic fungi. These results indicated that treatments with the environmentally friendly fungicides NPA and sulfur have fewer impacts on the phyllosphere fungal microbiome while maintaining the same control efficacy as the synthetic fungicide tebuconazole.

Head blight, which is caused by mycotoxin-producing fungi of the genus Fusarium, is an economically important crop disease. We assessed the potential of host-induced gene silencing targeting the fungal cytochrome P450 lanosterol C-14 alpha-demethylase (CYP51) genes, which are essential for ergosterol biosynthesis, to restrict fungal infection. In axenic cultures of Fusarium graminearum, in vitro feeding of CYP3RNA, a 791-nt double-stranded (ds)RNA complementary to CYP51A, CYP51B, and CYP51C, resulted in growth inhibition [half-maximum growth inhibition (IC50) = 1.2 nM] as well as altered fungal morphology, similar to that observed after treatment with the azole fungicide tebuconazole, for which the CYP51 enzyme is a target. Expression of the same dsRNA in Arabidopsis and barley rendered susceptible plants highly resistant to fungal infection. Microscopic analysis revealed that mycelium formation on CYP3RNA-expressing leaves was restricted to the inoculation sites, and that inoculated barley caryopses were virtually free of fungal hyphae. This inhibition of fungal growth correlated with in planta production of siRNAs corresponding to the targeted CYP51 sequences, as well as highly efficient silencing of the fungal CYP51 genes. The high efficiency of fungal inhibition suggests that host-induced gene-silencing targeting of the CYP51 genes is an alternative to chemical treatments for the control of devastating fungal diseases.

Resistance to triazoles in Aspergillus fumigatus has been reported in azole-naive patients in Europe, Asia, Australia and North America. This resistance has been linked to fungicide-driven mutations in the cyp51A gene and its promoter region. We investigated the presence of environmental azole-resistant A. fumigatus strains related to the use of azole fungicides in Colombia. Soil samples were collected from flower beds, flower fields and public gardens from the outskirts, suburbs and city centre of Bogotá. Out of the 86 soil samples taken, 17 (19.8%) grew A. fumigatus of whom eight (9.3%) contained 40 strains able to grow on azole-containing itraconazole and/or voriconazole supplemented media. All but one triazole-resistant strains were isolated from soil samples collected from flower fields and flower beds (39/40). Importantly, the majority had the TR 46 /Y121F/T289A, TR 34 /L98H, and TR 53 molecular resistance mechanisms and one azole resistant strain had a wild-type cyp51A gene. Soil samples from flower fields and beds contained 4 azole fungicides (penconazole, difenoconazole, tetraconazole and tebuconazole) above the limit of detection. Our findings underline the need for extensive investigations to determine azole-resistant A. fumigatus prevalence in both clinical and environmental samples in other regions of Latin America.

Carbendazim (MBC) (methyl-2-benzimidazole carbamate) and tebuconazole (TBZ) ((RS)-1-(4-chlorophenyl)-4,4-dimethyl-3-(1H-1,2,4-triazol-1-ylmethyl)pentan-3-ol) are widely used in agriculture for the prevention and control of fungal diseases. Solid lipid nanoparticles and polymeric nanocapsules are carrier systems that offer advantages including changes in the release profiles of bioactive compounds and their transfer to the site of action, reduced losses due to leaching or degradation and decreased toxicity in the environment and humans. The objective of this study was to prepare these two types of nanoparticle as carrier systems for a combination of TBZ and MBC and then investigate the release profiles of the fungicides as well as the stabilities and cytotoxicities of the formulations. Both nanoparticle systems presented high association efficiency (>99%), indicating good interaction between the fungicides and the nanoparticles. The release profiles of MBC and TBZ were modified when the compounds were loaded in the nanoparticles and cytotoxicity assays showed that encapsulation of the fungicides decreased their toxicity. These fungicide systems offer new options for the treatment and prevention of fungal diseases in plants.

ObjectiveChildren from agricultural families are often para-occupationally exposed to pesticides. We associated urinary biomarkers of pesticide exposure with relative telomere length (rTL) and mtDNA copy number (mtDNA-cn) in 270 5-year-old children from agricultural families who participated in the Infants’ Environmental (ISA) birth cohort.MethodsWe repeatedly measured biomarkers of pesticide exposure in maternal urine during pregnancy and in children’s urine at 5-years. rTL and mtDNA-cn were determined in children’s saliva, relative to a single-copy hemoglobin beta gene, using real-time PCR. We associated log10 transformed mean urinary biomarker concentrations with log10 transformed rTL and mtDNA-cn, using separate multivariate linear regression and generalized additive models, and adjusted for possible confounders.ResultsExposure to fungicides and 2,4-D was associated with changes in rTL and mtDNA-cn. Higher prenatal hydroxy-thiabendazole was associated with shorter rTL, while current 2,4-D was associated with longer rTL:%-change-in-β (95%CI) = -0.19 (-0.36, -0.02) and = 0.38 (0.01, 0.75) per tenfold increase in exposure, respectively. In addition, prenatal hydroxy-pyrimethanil was slightly associated with mtDNA-cn: β =0.33 (-0.05, 0.70) and 2,4-D was non-linearly associated with mtDNA-cn (estimated degrees of freedom of smoothed beta = 2.78, p=0.04), while current urinary ethylene thiourea (biomarker of mancozeb) and hydroxy-tebuconazole were associated with decreased and increased mtDNA-cn:%-change-in-β (95%CI) = -0.84 (1.71, 0.05) and 0.71 (0.01, 1.40), respectively. Biomarkers of pyrethroid and chlorpyrifos exposure were not associated with rTL or mtDNA-cn.ConclusionsPrenatal and childhood exposure to fungicides and 2,4-D may alter rTL and mtDNA-cn, which is of concern as shorter TL may reflect an increased risk of age-related diseases. Longer TL might reflect changes in cellular aging, including increased cellular mutation risks. Finally, increased mtDNA-cn indicates compensation for oxidative stress, while decreased levels reflect oxidative stress.