azoxystrobin and pyrimethanil

Continuous fungicide spraying is required to eliminate fungal pathogens on grapes. However, this practice is associated with several risks, including contamination and environmental imbalance, as well as toxicity to operators and the induction of resistance in pathogens. In addition, a strong correlation has been reported between the presence of fungicides and the occurrence of issues during alcoholic fermentation, resulting in negative impacts on the sensory quality of the final products. Numerous studies have evaluated residue concentrations of phytosanitary products in grapes, juices, and wines, and a significant number of studies have assessed the impact of different agrochemicals on bioprocesses. However, a review compiling the key results of these studies is currently lacking. This review incorporates results obtained in the last decade from research on the presence of fungicide residues, including azoxystrobin, boscalid, captan, copper, fenhexamid, folpet, pyraclostrobin, pyrimethanil and tebuconazole, and their effects on fermentation kinetics. Practical solutions to mitigate these problems, both in vineyards and industry, are also presented and discussed. This review highlights the constant high fungicidal agent concentrations (greater than 1 or 2 mg L

Topics: Fermentation; Food Contamination; Fungicides, Industrial; Humans; Pyrimidines; Saccharomyces cerevisiae; Strobilurins; Triazoles; Wine

The aim of this study was to investigate the bioaccessibility of pesticide residues in blueberries (commercial and sample from controlled field trial) from Serbia, involving the presence of a complex food matrix and to assess the potential risk to human health. The presence of nine active substances (azoxystrobin, boscalid, fludioxonil, cyprodinil, pyrimethanil, pyridaben, pyriproxyfen, acetamiprid and thiametoxam) in initial blueberry samples was determined in concentration range from 5.15 μg/kg for thiametoxam to 187 μg/kg for azoxystrobin. Clothianidin, metabolite of thiametoxam, was not detected in any blueberry sample. However, after in vitro digestion, the content of initially detected pesticides residues was significantly decreased or it was below limit of quantification resulting in the total bioaccessibility of about 15%. Azoxystrobin, pyrimethanil and fludioxonil was quantified in digestive juice at concentrations which were about 81%, 37% and 10% less than the inital concentration, respectively. The presence of food matrix during digestion of blueberries even more severely reduced concentration of pesticide residues (total bioaccessibility was about 7%) compared to digestion without the food matrix. Only azoxystrobin was quantified after digestion with food matrix in concentration of 27 μg/kg in sample from controlled field trial and detected in two commercial samples but below the limit of quantification. Furthermore, chronic risk assessment indicated that risk is acceptable for the health of different human subpopulation groups. The current study on pesticides residues, most commonly applied on blueberries, provides for the first time an insight into their bioaccessibility under conditions that mimic physiological environment of human digestive tract.

Topics: Blueberry Plants; Dioxoles; Food Contamination; Fruit; Humans; Pesticide Residues; Pyrimidines; Pyrroles; Serbia; Strobilurins

Plant protection products (PPPs) have been found increasingly in the environment. They pose a huge threat to bees, contributing to honeybee colony losses and consequently to enormous economic losses. Therefore, this field investigation was designed to determine whether their active ingredients (AIs) were transferred from raspberry plants to beehives located in the immediate neighbourhood of the crop and to what extent they were transferred. Every week for 2 months, samples of soil, raspberry leaves, flowers and fruits, worker bees, honeybee brood, and honey were collected and analysed for the presence of propyzamide, chlorpyrifos, iprodione, pyraclostrobin, boscalid, cypermethrin, difenoconazole, azoxystrobin, and pyrimethanil residues. Five of these substances were found in the worker bee bodies. Chlorpyrifos, applied to only the soil through the irrigation system, also was detected in the brood. A small amount of boscalid was noted in the honey, but its residues did not exceed the maximum residue level. For chlorpyrifos, boscalid, and pyrimethanil, a positive correlation between the occurrence of PPPs in the crops and the beehives was found. Statistical methods confirmed that the application of PPPs on a raspberry plantation, as an example of nectar-secreting plants, was linked to the transfer of their AIs to beehives.

Topics: Animals; Bees; Benzamides; Biphenyl Compounds; Chlorpyrifos; Crops, Agricultural; Fruit; Honey; Insecticides; Niacinamide; Pesticide Residues; Plant Leaves; Poland; Pyrethrins; Pyrimidines; Rubus; Strobilurins

Botrytis fruit rot, caused by Botrytis cinerea, is one of the most important strawberry diseases worldwide, and fungicide applications are often used to manage the disease in commercial production. Isolates of B. cinerea were collected from conventional and organic strawberry fields in four Brazilian States from 2013 to 2015 and their sensitivity to the main single-site mode-of action fungicides used in Brazil was tested. Resistance to azoxystrobin, iprodione, pyrimethanil, and thiophanate-methyl was found and values for effective concentration that inhibited mycelial growth by 50% were higher than 71.9, 1.2, 5.0, and 688 µg/ml, respectively, regardless the production system. Resistance to these fungicides was observed in 87.5, 76.6, 23.4, and 92.2% of isolates from conventional fields and 31.4, 22.9, 14.3, and 51.4% of isolates from organic fields, respectively. Moreover, frequencies of isolates with multiple fungicide resistance to the four active ingredients were 20.6 and 2.8% whereas 6.3 and 27.8% were sensitive to the four fungicides for conventional and organic areas, respectively. Molecular analyses of the cytochrome b, β-tubulin, and bos1 genes revealed the presence of G143A; E198A; and I365 N/S, Q369P, or N373S mutations, respectively, in resistant isolates of B. cinerea. Field rates of fungicides sprayed preventively to inoculated strawberry fruit failed to control disease caused by the respective resistant isolates.

Topics: Aminoimidazole Carboxamide; Botrytis; Brazil; Drug Resistance, Fungal; Fragaria; Fruit; Fungicides, Industrial; Hydantoins; Plant Diseases; Pyrimidines; Strobilurins; Thiophanate

Gray mold caused by Botrytis cinerea is an emerging postharvest disease affecting stored mandarin fruit in California. To develop effective control programs, fungicide sensitivities to four citrus postharvest fungicides were determined. One hundred B. cinerea isolates each in 2015 and 2016 were obtained from decayed fruit collected within packinghouses and tested for resistance to the fungicides. Sensitivity to azoxystrobin was examined based on the point mutation in the cyt b gene using PCR, while resistance to fludioxonil, pyrimethanil, and thiabendazole was examined on fungicide-amended media. For azoxystrobin, 83 and 98% of the isolates were resistant in 2015 and 2016, respectively. For pyrimethanil, 71 and 93% were resistant in 2015 and 2016, respectively. For thiabendazole, 63 and 68% were resistant in 2015 and 2016, respectively. No fludioxonil resistance was detected in both years. Five fungicide-resistant phenotypes were detected, and the most common phenotype was triple resistance to azoxystrobin, pyrimethanil, and thiabendazole, accounting for 59 and 65% in 2015 and 2016, respectively. Of the 200 B. cinerea isolates, 5, 23.5, and 62% were resistant to one, two, or three classes of fungicides, respectively. Inoculation tests were conducted to evaluate if the fungicides at label rates controlled various resistant phenotypes on fruit. Most fungicides failed to control gray mold on mandarin fruit inoculated with the respective fungicide resistant phenotypes. Our results suggest that alternative control methods need to be integrated into existing decay control programs to target this emerging disease on mandarin fruit.

Topics: Botrytis; California; Citrus; Dioxoles; Drug Resistance, Fungal; Fruit; Fungicides, Industrial; Phenotype; Plant Diseases; Pyrimidines; Pyrroles; Strobilurins; Thiabendazole

A simple and accurate procedure was developed for the determination of seven fungicides, azoxystrobin (AZO), diphenyl (DP), fludioxonil (FLUDI), imazalil (IMZ), o-phenylphenol (OPP), pyrimethanil (PYRI) and thiabendazole (TBZ), in citrus fruits. The citrus fruit sample was extracted with acetonitrile and cleaned up with a graphite carbon/aminopropyl silanized silica gel solid-phase extraction cartridge using acetonitrile-toluene (3 : 1, v/v) as the eluent. Triphenylene was used as an internal standard (I.S.) at the concentration of 0.5 μg/mL. The sample solution was subjected to GC-MS utilizing the matrix-matched standard solution method. The recoveries of AZO, FLUDI, IMZ, OPP, PYRI and TBZ spiked in domestic citrus fruits (Satsuma mandarin) at the level of 0.01-10.0 μg/g were 72.8-104% and the limits of quantification were 0.01 μg/g. The recoveries of DP spiked in domestic citrus fruits at the level of 0.01-70.0 μg/g were 70.8-80.4% and the limit of quantification was 0.01 μg/g. The proposed method was applied to the determination of fungicides in citrus fruits purchased in various markets.

Topics: Biphenyl Compounds; Citrus; Dioxoles; Food Analysis; Fungicides, Industrial; Gas Chromatography-Mass Spectrometry; Imidazoles; Methacrylates; Pyrimidines; Pyrroles; Strobilurins; Thiabendazole

The extreme specificity of immunoaffinity chromatography (IAC) columns coupled to the high sensitivity of ion mobility spectrometry (IMS) measurements makes this combination really useful for rapid, selective, and sensitive determination of a high variety of analytes in different samples. The capabilities of the IAC-IMS coupling have been highlighted under three different scenarios: (i) multiclass residue analysis using a single IAC column, (ii) multiclass residue analysis using stacked IAC columns, and (iii) isomer analysis. In the first case, the determination of three strobilurin fungicides - azoxystrobin, picoxystrobin, and pyraclostrobin - in water and strawberry juice was considered, obtaining limits of quantification (LOQs) from 11 to 63μgL(-1). Recoveries from 96 to 106% for water, and from 67 to 104% for strawberry juice were obtained. In the second case, anilinopyrimidine compounds, including two analytes with similar drift time, were selectively retained in different IAC columns and analyzed after independent elution in commercial wine samples by IMS. LOQ values of 16, 14 and 12μgL(-1) were obtained for pyrimethanil, mepanipyrim, and cyprodinil, respectively. The obtained recoveries for wine samples spiked with 25 and 100μgL(-1) were from 82 to 123%. Additionally, the stacked IAC columns concept was applied to the separation of Z and E isomers of azoxystrobin that were selectively retained in specific IAC columns and quantified by IMS. Recoveries between 91 and 94% were obtained for both isomers in water samples.

Topics: Acrylates; Carbamates; Chromatography, Affinity; Fragaria; Fruit and Vegetable Juices; Fungicides, Industrial; Methacrylates; Pyrazoles; Pyridines; Pyrimidines; Sensitivity and Specificity; Stereoisomerism; Strobilurins; Water; Wine

An in-syringe demulsified dispersive liquid-liquid microextraction (ISD-DLLME) technique was developed using low-density extraction solvents for the highly sensitive determination of the three trace fungicides (azoxystrobin, diethofencarb and pyrimethanil) in water samples by high performance liquid chromatography-mass spectrometry chromatography-diode array detector/electrospray ionisation mass spectrometry. In the proposed technique, a 5-mL syringe was used as an extraction, separation and preconcentration container. The emulsion was obtained after the mixture of toluene (extraction solvent) and methanol (dispersive solvent) was injected into the aqueous bulk of the syringe. The obtained emulsion cleared into two phases without centrifugation, when an aliquot of methanol was introduced as a demulsifier. The separated floating organic extraction solvent was impelled and collected into a pipette tip fitted to the tip of the syringe. Under the optimal conditions, the enrichment factors for azoxystrobin, diethofencarb and pyrimethanil were 239, 200, 195, respectively. The limits of detection, calculated as three times the signal-to-noise ratio (SN(-1)), were 0.026 μg L(-1) for azoxystrobin, 0.071 μg L(-1) for diethofencarb and 0.040 μg L(-1) for pyrimethanil. The repeatability study was carried out by extracting the spiked water samples at concentration levels of 0.02 μg mL(-1) for all the three fungicides. The relative standard deviations varied between 4.9 and 8.2% (n=5). The recoveries of all the three fungicides from tap, lake and rain water samples at spiking levels of 0.2, 1, 5 μg L(-1) were in the range of 90.0-105.0%, 86.0-114.0% and 88.6-110.0%, respectively. The proposed ISD-DLLME technique was demonstrated to be simple, practical and efficient for the determination of different kinds of fungicide residues in real water samples.

Topics: Chromatography, High Pressure Liquid; Emulsions; Environmental Monitoring; Fungicides, Industrial; Limit of Detection; Liquid Phase Microextraction; Mass Spectrometry; Methacrylates; Methanol; Pesticide Residues; Phenylcarbamates; Pyrimidines; Reproducibility of Results; Strobilurins; Toluene; Water Pollutants, Chemical

To provide an assessment of the occurrence of fungicides in water resources, the US Geological Survey used a newly developed analytical method to measure 33 fungicides and an additional 57 current-use pesticides in water samples from streams, ponds, and shallow groundwater in areas of intense fungicide use within three geographic areas across the United States. Sampling sites were selected near or within farms using prophylactic fungicides at rates and types typical of their geographic location. At least one fungicide was detected in 75% of the surface waters and 58% of the groundwater wells sampled. Twelve fungicides were detected including boscalid (72%), azoxystrobin (51%), pyraclostrobin (40%), chlorothalonil (38%) and pyrimethanil (28%). Boscalid, a carboxamide fungicide registered for use in the US in 2003, was detected more frequently than atrazine and metolachlor, two herbicides that are typically the most frequently occurring pesticides in many large-scale water quality studies. Fungicide concentrations ranged from less than the method detection limit to approximately 2000 ngL(-1). Currently, limited toxicological data for non-target species exists and the environmental impacts are largely unknown. The results of this study indicate the importance of including fungicides in pesticide monitoring programs, particularly in areas where crops are grown that require frequent treatments to prevent fungal diseases.

Topics: Biphenyl Compounds; Carbamates; Environmental Monitoring; Fungicides, Industrial; Groundwater; Idaho; Maine; Methacrylates; Niacinamide; Nitriles; Pyrazoles; Pyrimidines; Strobilurins; Water Pollutants, Chemical; Wisconsin

Although there is some evidence regarding the effect of solarization and biosolarization on pesticide degradation, information is still scarce. The aim of this study was to determine the effect of these disinfection techniques on the degradation of eight fungicides (azoxystrobin, kresoxin methyl, tebuconazole, hexaconazole, triadimenol, cyprodinil, pyrimethanil and fludioxonil) commonly used in pepper crops under greenhouse cultivation. Seventy-five 17-L pots filled with clay-loam soil were placed in a greenhouse during the summer season and then contaminated with the studied fungicides. Treatments consisted of different disinfection treatments, including a control without disinfection, solarization and biosolarization. For the solarization and biosolarization treatments, low-density polyethylene film was used as cover. Five pots per treatment were sampled periodically up to 90d after the beginning of each treatment and fungicide residues were analyzed by GC/MS. The results showed that both solarization and biosolarization enhanced fungicide dissipation rates with regard to the control treatment, an effect which was attributed to the increased soil temperature. Most of the fungicides studied showed similar behavior under solarization and biosolarization conditions. However, triadimenol was degraded to a greater extent in the biosolarization than in the solarization treatment, while fludioxonil behaved in the opposite way. The results confirm that both solarization and biosolarization contribute to pesticide dissipation and can therefore be considered alongside other soil disinfection techniques, as a bioremediation tool for pesticide-polluted soils.

Topics: Dioxoles; Environmental Restoration and Remediation; Fungicides, Industrial; Hot Temperature; Methacrylates; Phenylacetates; Photochemical Processes; Pyrimidines; Pyrroles; Soil; Soil Pollutants; Strobilurins; Triazoles

ABSTRACT Fungicide resistance was identified in natural populations of Penicillium digitatum, the causal agent of green mold of citrus, to two of three new postharvest fungicides before their commercial use. Using a new air-sampling method where large populations of the pathogen in citrus packinghouses were exposed to agar plates with a continuous, wide-range fungicide concentration gradient, isolates with reduced sensitivity to fludioxonil or pyrimethanil were obtained. Resistance frequencies to fludioxonil and pyrimethanil were calculated as 9.5 x 10(-7) to 1.5 x 10(-5) and 7.3 x 10(-6) to 6.2 x 10(-5), respectively. No isolates resistant to azoxystrobin were detected. Isolates with reduced sensitivity to fludioxonil or pyrimethanil were also obtained in laboratory selection studies, where high concentrations of conidial mixtures of isolates sensitive to the three fungicides were plated onto agar amended with each fungicide at 10 microg/ml. Isolates obtained from fludioxonil selection plates in laboratory and packinghouse experiments were placed into two categories based on mycelial growth: moderately resistant isolates had 50% effective concentration (EC(50)) values of 0.1 to 0.82 microg/ml and highly resistant isolates had EC(50) values > 1.5 microg/ml. Isolates resistant to pyrimethanil all had EC(50) values >8 microg/ml. Representative isolates of the two categories with reduced sensitivity to fludioxonil varied widely in their virulence and sporulation capacity as measured by the incidence of decay and degree of sporulation on inoculated fruit, respectively, whereas pyrimethanil-resistant isolates were mostly similar to the wild-type isolate. Fungicide sensitivity characteristics for isolates from fludioxonil and pyrimethanil selection plates remained stable after passages on nonamended agar, and disease could not be controlled after treatment with the respective fungicides. Types of fungicide resistance were visualized on thiabendazole- (TBZ) and imazalil-amended selection plates that were exposed in packinghouses where resistance to these fungicides was known to occur. The qualitative, single-site resistance to the benzimidazole TBZ was visualized by two distinct subpopulations in regard to fungicide sensitivity, whereas the quantitative, multi-site resistance to the demethylation inhibitor imazalil was apparent as a continuous density gradient of colonies along the fungicide concentration gradient. Types of resistance could not be assigned to fl

Topics: Air Microbiology; Citrus; Dioxoles; Drug Resistance, Multiple, Fungal; Fungicides, Industrial; Methacrylates; Penicillium; Pyrimidines; Pyrroles; Selection, Genetic; Strobilurins

Residues of the pesticides azoxystrobin, fenhexamid and pyrimethanil were determined in strawberry after field treatment. The effect of 'home' washing with tap water and a commercially available vegetable detergent on residue levels was also studied. After treatment, azoxystrobin and pyrimethanil residues on strawberry were on average 0.55 and 2.98 mg kg(-1), respectively, values below the maximum residue level (MRL) fixed by the European Union (2.0 and 5 mg kg(-1), respectively), while fenhexamid residues were on average 2.99 mg kg(-1), which is very close to the MRL of 3.0 mg kg(-1), but some samples were over the MRL. Thereafter, all residues declined, with a half-life of about 8 days (azoxystrobin and fenhexamid) and 4.8 days (pyrimethanil). Washing the fruit with tap water reduced the residues of azoxystrobin and fenhexamid but did not affect pyrimethanil residues. Finally, when fruits were washed with a commercial detergent, greater amounts were removed (about 45% of azoxystrobin and pyrimethanil and 60% of fenhexamid).

Topics: Acrylates; Amides; Food Contamination; Food Handling; Fragaria; Fruit; Fungicides, Industrial; Half-Life; Methacrylates; Pesticide Residues; Pyrimidines; Strobilurins

The disappearance of azoxystrobin, pyrimethanil, cyprodinil, and fludioxonil on tomatoes in greenhouse was studied. At the preharvest interval, except for cyprodinil, the pesticide residues were below the MRL fixed in Italy. The mechanism of disappearance studied with model systems shows that the decrease in residues was due to codistillation and photodegradation in pyrimethanil, to photodegradation in fludioxonil, and to evaporation and codistillation in cyprodinil. Azoxystrobin residues were stable during all experiments.

Topics: Acrylates; Agriculture; Dioxoles; Fungicides, Industrial; Methacrylates; Pesticide Residues; Photochemistry; Pyrimidines; Pyrroles; Solanum lycopersicum; Strobilurins; Sunlight