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Ramularia leaf spot of barley, caused by Ramularia collo-cygni has become a serious disease threat to barley production. By inducing necrotic lesions, the disease expiates the onset of leaf senescence, which can result in significant grain yield and quality losses. In addition to surviving between seasons in trash, stubble and volunteers, R. collo-cygni can be transmitted from seed to emerging seedlings. As a potential additional means of transmission it may also pose a risk for the spread of specific traits such as fungicide resistance. In the present study, we screened Irish barley seed stocks harvested in the years 2015–2017 for the presence of R. collo-cygni using qPCR, and subsequently using an amplicon sequencing assay screened for the presence of alleles in the SDHC gene of R. collo-cygni associated with SDHI resistance. Over the three year period > 60% of the samples screened had detectable levels of R. collo-cygni present. In a subsample of these five alleles associated with resistance (SDHC—N87S, G91R, H145R, R152M and H153R) were detected. The prevalence of the key alleles C-N87S and C-H146R remained stable over the three year period, and was similar to that detected amongst an isolate collection established in 2022. [ABSTRACT FROM AUTHOR]

Plasmopara viticola is controlled by fungicides with different modes of action, which include zoxamide. Zoxamide was developed in 1998 by Dow AgroSciences LIC (Indianapolis, IN) and has been commercialized since 2001 by Rohm and Haas Company. This fungicide is highly effective against oomycetes, used for foliar application in vine crops, potato, and other vegetables to control oomycete-induced diseases. Zoxamide acts by causing mitotic arrest by binding to β-tubulin, inhibiting tubulin polymerization and cell division of the pathogen. In the past three decades, the management of fungicide resistance has emerged as a significant concern for both growers and regulatory authorities; this is primarily due to the substantial increase in resistance, in terms of occurrence and spread, towards most fungicide groups. The monitoring of the effectiveness of fungicides is the only way to accurately identify as soon as possible the onset of resistance. In this study, we were interested in tracking the changes in the sensitivity of zoxamide to P. viticola populations collected during a 6-year monitoring (2017–2022) in two Italian locations: the autonomous province of Trento and the autonomous region of Friuli-Venezia Giulia. Bioassays on leaf discs were carried out, and EC50 and MIC values were elaborated. From our results, zoxamide showed for a long period of time high sensitivity, but over the last years we observed a change, as in 2022 most of the samples tested in these two regions showed MIC > 100 mg L−1. [ABSTRACT FROM AUTHOR]

The management of Asian soybean rust (ASR) involves a combination of cultural and chemical strategies. Phakopsora pachyrhizi-resistant isolates to fungicides have emerged, harboring point mutations in the CYP51, CYTB, and SDH genes. These mutants have advantages in regions extensively utilizing site-specific fungicides. However, the dynamics of selection within a single season remain poorly understood. Thus, this study aimed to investigate the potential selection of mutants following four fungicide applications of commercial mixtures (DMI, QoI, and SDHI), in contrast to untreated control plots. Disease progression and fungicide efficacy were also assessed. In the regions of Arapoti, Castro, Ponta Grossa in Paraná, and Itaberá in São Paulo, mutations on SDH, CYTB, and CYP51 genes were identified, leading to reduced sensitivity to SDHI, QoI, and DMI fungicides. F120L + Y131H mutations in the CYP51 gene were found in Arapoti and Ponta Grossa, and Y131F + K142R + I147T mutations in the CYP51 gene were identified in Itabera-SP. Population from Arapoti had the F129L mutation in the CYTB gene, with a high frequency (> 80%) in treated and untreated plots in Castro and Ponta Grossa. The C-I86F mutation in the SDH gene was detected in all municipalities, exhibiting statistical significance in Arapoti-PR compared to unthread control. In Itaberá, Arapoti, and Ponta Grossa disease severity reached 80% in untreated controls, while fungicides demonstrated efficacies of ranging from 50 to 90%. Importantly, all detected mutations were less frequent in untreated controls, underscoring the significance of anti-resistance management strategies. [ABSTRACT FROM AUTHOR]

Barley crops are at risk of being attacked by several leaf diseases. Net blotch, brown rust, Rhynchosporium and Ramularia leaf spot are among the most widespread and can cause severe attack and yield losses. Two trial protocols targeting Ramularia and net blotch, respectively, have been tested in several countries in 2021 and 2022. Ramularia trials were situated in Germany, Ireland, Scotland, and Denmark. The net blotch trials were placed in Denmark, Belgium, the UK, Germany, Finland, and France. In the two protocols, 12–13 different fungicide solutions including co-formulations of DMIs, SDHIs, QoIs, and multi-site inhibitors have been tested to compare efficacy and yield responses. Against Ramularia leaf spot, the fungicides were applied at GS 47–51 and against net blotch at GS 37–45. In six trials, the efficacy against Ramularia leaf spot was scored. The results showed a superior control from the co-formulation fluxapyroxad + metyltetraprole (78–100% control), but also solo mefentrifluconazole and the mixtures fluxapyroxad + mefentrifluconazole performed well (average 74–76% control). The mixture fluxapyroxad + metyltetraprole provided the best yield increase followed by Ascra Xpro. Folpet as a solo solution was inferior. Following the net blotch protocol, only three trials developed enough disease to rank the different fungicides; however, in five trials ranking against brown rust was also possible. Most treatments gave very good control of net blotch, and brown rust (> 80% control). The mixture fluxapyroxad + metyltetraprole delivered the best control against all diseases overall. Average yield responses from eight trials showed very similar increases from the tested fungicides. [ABSTRACT FROM AUTHOR]

The aim of the study was to provide information on the fungicide sensitivity of grape powdery mildew (Erysiphe necator) to some of the modes of action used for grape powdery mildew control with a focus on Europe. QoIs: most samples analysed in this study showed high values of the G143A mutation, which leads to low field performance of QoIs. Therefore, QoIs have lost their strength on grape powdery mildew control. DMIs: European wide sensitivity studies indicated that DMIs are only slightly and differently affected by the mutation Y136F, being frequently detected in the pathogens' cyp51 gene. Mefentrifluconazole was recently developed for grape powdery mildew control, and its sensitivity is even not affected by this mutation. APKs: resistance towards aryl-phenyl-ketones (APKs) has also been reported in various regions in Europe, and monitoring studies showed a heterogenous distribution from a sensitive situation towards populations with higher APK resistance. SDHIs: adaptation of Erysiphe necator to succinate dehydrogenase inhibitors (SDHI) is more recent and quite complex because different mutations can be found in the B and C-subunits of the SDH gene which have different effects on SDHIs. Different mutation pattern in different geographical regions have been found which could be the result of different SDHI use. Therefore, the implementation of resistance management strategies, including the use of various modes of action in alternation and mixture, are recommended for a sustainable disease management in grapes. [ABSTRACT FROM AUTHOR]

Picarbutrazox is the active ingredient of Vayantis®, a novel seed treatment fungicide developed by Syngenta and discovered by Nippon Soda. Vayantis® received registration from the US EPA in 2021. Picarbutrazox is a systemic fungicide and belongs to the tetrazolyloximes chemical group of fungicides, and its mode of action is still unknown (FRAC group U17). Picarbutrazox targets oomycete plant pathogens and controls diseases caused by Pythium, Phytophthora, and downy mildews. Picarbutrazox is in a new mode-of-action group with no known cross-resistance to other oomycete compounds. The sensitivity to Picarbutrazox of 528 isolates belonging to 40 different Pythium species was determined in vitro. Pythium isolates were collected from infected plants including corn, soybean, cotton, and other crops from 17 different states. Pythium isolates were also obtained from collections kept at universities. Isolates were identified at the species level using morphological and molecular tools. Mycelial growth inhibition was quantified using the following Picarbutrazox concentrations: 0, 0.00001, 0.0001, 0.001, 0.01, and 0.1 mg/L. All the species of Pythium tested were sensitive to Picarbutrazox. The sensitivity distribution (EC50 values) across all the Pythium species tested had a mean sensitivity of 0.000376 mg ai/L. The Picarbutrazox sensitivity of 40 species of Pythium species has been documented, and results demonstrate the high in vitro intrinsic activity of this fungicide to control Pythium species. The high potency of Picarbutrazox to control Pythium diseases in corn, soybeans, cotton, and other crops has also been demonstrated under field conditions when used as a seed treatment. Picarbutrazox, with its novel mode of action, will contribute to the management of potential fungicide resistance issues developed by other fungicide products controlling Pythium, including mefenoxam and ethaboxam. [ABSTRACT FROM AUTHOR]

Four new modes of action, oxathiapiprolin, fluopicolide, mandipropamid, and ethaboxam, have or are pending registrations on multiple tree crops in the USA including avocado, citrus, almond (and other tree nuts), and stone fruits to be used in sustainable anti-resistance rotation and mixture programs for managing Phytophthora diseases. All four fungicides are highly toxic in vitro against species of Phytophthora from different tree crops. Efficacy of foliar applications of oxathiapiprolin and mandipropamid for the management of citrus brown rot persisted for over 10 weeks. Still, residues could be removed to non-detectable levels by postharvest washing and brushing of fresh-market fruit. The four fungicides were highly effective in reducing root rot and crown/trunk cankers on tree crops and demonstrated acropetal systemic movement through the xylem after soil application and absorption by almond, citrus, and cherry roots. This was substantiated by reduced lesion size in stem inoculations of potted trees that were treated by soil applications or by in vitro bioassays and HPLC–MS–MS analyses of root, stem, and leaf extracts. Using an adapted Bromilow model that is based on the partition coefficient logP that indicates the lipo- or hydrophilicity and the acid dissociation constant pKa, mobility of ethaboxam, fluopicolide, mandipropamid, and oxathiapiprolin in plants was predicted, and this was supported by our studies. Mandipropamid and a mandipropamid–oxathiapiprolin pre-mixture are now registered as foliar applications for managing citrus brown rot, whereas oxathiapiprolin and fluopicolide are registered, and ethaboxam is pending registration as soil applications to control citrus root rot. Oxathiapiprolin has also been registered for soil use on almond and other nut crops, as well as avocado, and soil applications of mandipropamid are planned to be restricted to nursery use of multiple crops. [ABSTRACT FROM AUTHOR]

Efficient grapevine downy mildew control necessitates the implementation of anti-resistance strategies to ensure the ongoing efficacy of available substances and optimal disease control. With the gradual disappearance of multi-site fungicides from the market, reliance on single-site fungicides poses a long-term risk of selecting strains resistant to multiple modes of action. Challenges in disease management encompass selecting optimal spray programs and monitoring field population sensitivity. This study evaluated the efficacy of anti-resistance strategies, including two single-site fungicides (mandipropamid and oxathiapiprolin), on disease control and fungicide sensitivity through a combination of field trials and laboratory tests for the biological and molecular characterization of the pathogen populations over a three-year period (2019–2021). Mandipropamid, a cellulose synthase inhibitor, is used since a long time for downy mildew control, while oxathiapiprolin, an OxySterol Binding Protein homologue Inhibitor, was introduced recently. Field trials demonstrated effective disease control, even in the presence of mandipropamid-resistant strains (with G1105S/V mutations in PvCesA3) and revealed a pronounced selection and spread of resistance to both fungicides in the vineyard where disease pressure was higher. Characterizing pathogen strains remained a significant obstacle in sensitivity monitoring, hindering precise determination of resistance frequencies related to fungicide programs. Traditional techniques, in fact, lack the resolution required for high-throughput isolation and characterization of resistant individuals. To address this challenge, we propose utilizing flow cytometry and fluorescence-activated cell sorting on field sporangia populations, a method able to determine both the number of resistant isolates and isolate pathogen strains in a single assay. [ABSTRACT FROM AUTHOR]

Antifungal activity of newly synthesized submicrometer particles of the CsTeMoO6 complex metal oxide was studied. They were found to inhibit spore germination of active micromycete degraders of industrial materials both in the dark and under illumination. Illumination increased the fungicidal activity of the studied compounds due to their photocatalytic activity. This is the first report on production of micromycete-resistant composites of a number of polymers containing the complex metal oxides CsTeMoO6 and RbTe1.5W0.5O6. Upon addition of the studied complex oxides into the composition of the previously micromycete-sensitive materials, the latter were found to exhibit micromycete resistance both in the dark and under illumination. Treatment with light resulted in a more pronounced antifungal effect. [ABSTRACT FROM AUTHOR]

Rosa roxburghii (R. roxburghii) is a unique, edible, medicinal fruit rich in vitamin C found in Southwest China. Triadimefon (TDF) is a triazole fungicide that is widely used to control powdery mildew in R. roxburghii. To assess the safety of TDF in R. roxburghii, an LC-MS/MS method was developed for the simultaneous quantification of TDF and its major metabolite, triadimenol (TDN) in R. roxburghii. Both TDF and TDN showed high correlation coefficients (>0.999) for the solvent- and matrix-matched calibrations. The recovery rates of TDF and TDN in R. roxburghii ranged from 90.18% to 100.42%, with a relative standard deviation (RSD) of 1.25%–9.22%. The limit of quantification (LOQ) was 0.01 mg·kg−1. The half-life of TDF in R. roxburghii was between 2.74 and 3.07 days, with terminal residues ranging from < LOQ to 1.84 mg·kg−1. Recommended maximum residue limits (MRLs) and safe pre-harvest intervals (PHIs) for TDF in R. roxburghii were 0.5 mg·kg−1 and 21 days, respectively. This study provides essential data for TDF's safe and judicious use in R. roxburghii production. [ABSTRACT FROM AUTHOR]

Plenodomus lingam (Leptosphaeria maculans) and P. biglobosus (L. biglobosa) are fungi causing Phoma leaf spot/stem canker, an international damaging disease of oilseed rape (Brassica napus) and other brassicas. In Europe, fungicides used for disease management are mainly sterol 14α‐demethylase (CYP51) inhibitors (DMIs/azoles); quinone‐outside inhibitors (QoIs) and succinate dehydrogenase inhibitors (SDHIs) are also used. Decreased DMI sensitivity has emerged in Australian and eastern European P. lingam populations and is mediated by CYP51 promoter inserts resulting in target site overexpression. In this study using in vitro sensitivity testing, we report decreased DMI (prothioconazole‐desthio, mefentrifluconazole) sensitivity in modern western European P. lingam isolates (collected 2022–2023) compared to older baseline (1992–2005) isolates. Around 85% of modern western European P. lingam isolates collected, for which the CYP51 promoter region was sequenced, carried a promoter insert, but target site alterations were not detected. Six different CYP51 promoter inserts were identified, most commonly a 237 bp fragment of the Sahana transposable element. Inserts were associated with an approximately 3‐ to 10‐fold decrease in sensitivity to the DMIs tested. In contrast to P. lingam, PCR screening revealed CYP51 promoter inserts were absent in modern western European P. biglobosus isolates (2021–2023). Combined data indicate P. lingam isolates lacking an insert were similarly (or slightly more) sensitive to the DMIs tested for P. biglobosus, whereas those carrying an insert were slightly less sensitive than P. biglobosus. No evidence for substantive sensitivity shifts to the QoI (pyraclostrobin) or SDHI (boscalid) fungicides tested was obtained for either Plenodomus species. [ABSTRACT FROM AUTHOR]

Wheat sharp eyespot, mainly caused by Rhizoctonia cerealis, is a soil-borne fungal disease. Since the mid-1990s, it has gradually risen from a minor disease to a major one in the Huang-Huai wheat-growing region. Resistant strains of common fungicides have emerged. The inhibitory activity of newly commercialized succinate dehydrogenase inhibitors (SDHIs) against R. cerealis has not been reported yet. In this study, three strains of R. cerealis (ZMDBY-9, JZWZ-8, and ZMDBY-6) were selected to determine the inhibitory activity of ten SDHIs fungicides including carboxin, flutolanil, thifluzamide, boscalid, isopyrazam, fluxapyroxad, benzovindiflupyr, fluopyram, pydiflumetofen and pyraziflumid, using mycelial growth rate method. Homology modeling and molecular docking were used to investigate the binding modes between RcSDH bcd and these ten SDHIs fungicides as well as analyze the correlation between binding energy and inhibitory effect. The results obtained from the mycelial growth rate method showed that benzovindiflupyr and fluxapyroxad exhibited higher inhibition effects with mean EC50 values less than 0.1 mg/L; while fluopyram and pydiflumetofen displayed weaker inhibitory activities with mean EC50 values greater than 1 mg/L; for the mean EC50 values of other six fungicides ranged from 0.1 to 0.6 mg/L. Molecular docking results indicated that among these ten SDHIs fungicides, those containing pyrazole-4-carboxamide structure possessed better inhibitory activities against R.cerealis and had lower binding energy. There was a certain correlation between the inhibitory activities and binding energies of seven fungicides: fungicides with stronger inhibition often had lower binding energies. The research findings of this study provide references for the application of SDHI fungicides in the chemical control of wheat sharp eyespot and the compound design based on succinate dehydrogenase. [ABSTRACT FROM AUTHOR]

Myosins constitute a class of functional proteins that are widely found in eukaryotic organisms and play important roles in the process of various life activities in the cells of living organisms. In addition, myosins derived from phytopathogenic fungi significantly also have significant impacts on the growth and development of fungi and their pathogenicity. In light of these characteristics, more and more researchers are directing their attention towards the development of pesticides targeting myosin. Designing inhibitors based on myosins from phytopathogenic fungi to develop fungicides with novel mechanisms of action will be an important tool for preventing and controlling plant diseases, thereby ensuring food security. This paper focuses on the research progress of myosins and their inhibitors in phytopathogenic fungal and mainly reviews the structural features and biochemical functions, as well as myosin inhibitor fungicides reported in recent years, which can provide a reference for the discovery of myosin target-directed lead compounds of phytopathogenic fungi and the rational design of the active molecules of new pesticides. [ABSTRACT FROM AUTHOR]

Azole-resistant Aspergillus fumigatus (ARAf) fungi have been found inconsistently in the environment in Denmark since 2010. During 2018-2020, nationwide surveillance of clinical A. fumigatus fungi reported environmental TR34/L98H or TR46/Y121F/T289A resistance mutations in 3.6% of isolates, prompting environmental sampling for ARAf and azole fungicides and investigation for selection of ARAf in field and microcosmos experiments. ARAf was ubiquitous (20% of 366 samples; 16% TR34/L98H- and 4% TR46/Y121F/T289A-related mechanisms), constituting 4.2% of 4,538 A. fumigatus isolates. The highest proportions were in flower- and compost-related samples but were not correlated with azole-fungicide application concentrations. Genotyping showed clustering of tandem repeat-related ARAf and overlaps with clinical isolates in Denmark. A. fumigatus fungi grew poorly in the field experiment with no postapplication change in ARAf proportions. However, in microcosmos experiments, a sustained complete (tebuconazole) or partial (prothioconazole) inhibition against wild-type A. fumigatus but not ARAf indicated that, under some conditions, azole fungicides may favor growth of ARAf in soil. [ABSTRACT FROM AUTHOR]

Phytoseiids are an essential group of predators that feed on phytophagous mites. Studies on the detrimental impacts of plant protection chemicals on phytoseiids are crucial for their successful utilization as biocontrol agents. In the present study, the toxicity and side effects of fungicides on the predatory mite Neoseiulus longispinosus (Evans) (Acari: Phytoseiidae) were examined fed on Tetranychus urticae Koch (Acari: Tetranychidae) in tomato under laboratory conditions. Gravid females of N. longispinosus were exposed to fungicides using the leaf dip method for 48 hours. Results showed that the fungicide metalaxyl + mancozeb caused the highest mortality of 60%, followed by mancozeb (52.50%), copper oxychloride (35%), and thiophanate methyl (17.50%). Additionally, residual toxicity from metalaxyl + mancozeb and mancozeb treatments significantly affected the biological and life table parameters of the predatory mite. However, the effects of the other two fungicides were moderate to negligible, implying that the application of metalaxyl + mancozeb and mancozeb could negatively impact the biological performance of N. longispinosus in tomato fields. [ABSTRACT FROM AUTHOR]

Fungal diseases in Brazilian regions with tropical and subtropical climates reduce the production potential of corn crops. The use of fungicides is one of the strategies to maintain productivity. This study evaluated the agronomic performance and grain quality of corn hybrids associated with the preventive use of fungicides in subtropical environments. Six experiments were conducted in Santa Maria-RS, São Vicente do Sul-RS, and Frederico Westphalen-RS during two sowing seasons. The experiment was conducted in a randomized complete block design with a split-plot arrangement, in which the main plot consisted of two levels of the fungicide factor (with and without) and the sub-plot consisted of six levels of corn hybrids (AG9025, AS1730, P3016, MG300, DKB230, and FEROZ). A total of 216 experimental plots were evaluated for grain productivity, and eight plants per plot were evaluated for other traits, totaling 1,728 evaluated plants. Therefore, environmental conditions influence the interaction between the factors of fungicide use and hybrid cultivar positioning, with no significant interaction in years with a water deficit. Early sowings in subtropical environments indicate better agronomic performance and a lower percentage of moldy grains regardless of the cultivation location, contributing to grain quality. [ABSTRACT FROM AUTHOR]

Bumble bees are declining across the globe. The causes of this decline have been attributed to a variety of stressors, including pesticides. Fungicides are a type of pesticide that has been understudied in the context of bumble bee health. As a result, fungicides are often applied to flowering plants without consideration of pollinator exposure. Recent work demonstrates that fungicides have sublethal effects in bumble bees, but little is known about how much fungicide it takes to cause these sublethal effects. To address this gap in the literature, we fed microcolonies of the common eastern bumble bee (Bombus impatiens CressonHymenoptera: ApidaeHymenoptera: ApidaeHymenoptera: ApidaeHymenoptera: Apidae) pollen contaminated with a range of fungicide concentrations. We chose these concentrations based on the range of fungicide concentrations in pollen and nectar that were reported in the literature. Results revealed that later-stage pupae and newly emerged males are potentially sensitive to fungicide exposure, showing smaller size and reduced fat reserves at intermediate levels of contamination. Compared to the control, intermediated levels of fungicide-contaminated pollen led to increased pupal mortality and delayed male emergence. Contrary to expectations, higher fungicide levels did not exhibit a linear relationship with negative impacts, suggesting nuanced effects. Because body size and emergence timing are important aspects of bumble bee reproductive behavior, results have implications for mating success, potentially disrupting colony development. [ABSTRACT FROM AUTHOR]

Florida's strawberry industry is currently valued at $511 million annually but faces challenges from pathogens and arthropod pests especially Tetranychus urticae Koch (twospotted spider mite) and Scirtothrips dorsalis Hood (chilli thrips). Predatory mites, particularly Neoseiulus cucumeris Oudemans, Neoseiulus californicus McGregor, and Amblyseius swirskii Athias-Henriot, play a crucial role in pest management. However, there are concerns regarding how these biological control agents are affected by fungicides used in current pathogen management strategies. This study assessed the residual effects of commonly used fungicides in strawberries on the survival, feeding, and oviposition of these predatory mites. Commercially sourced predatory mites were reared on S. dorsalis larvae, and gravid female predators placed on fungicide treated strawberry leaf discs in a Munger cell for 120 h. Fungicides tested included two formulations of Captan, hydrogen peroxide + peroxyacetic acid, cyprodinil + fludioxonil, tetramethylthiuram disulfide, cyflufenamid and a control. All fungicides tested had an impact on the survival, feeding, and oviposition of the predators. Among the fungicide treatments, the lowest predator survival was observed in the cyprodinil + fludioxonil treatment, while the highest was observed in the hydrogen peroxide + peroxyacetic acid and tetramethylthiuram disulfide treatments. In all treatments, feeding and oviposition greatly varied among predators; specifically, N. cucumeris and A. swirskii had the lowest prey consumption, while N. californicus had the highest. These findings highlight the potential incompatibility between fungicides and predatory mites and demonstrate the need for the development of a fungicide rotation program tailored to the different susceptibilities of predators to fungicides. [ABSTRACT FROM AUTHOR]

BACKGROUND: Grapevine downy mildew, caused by Plasmopara viticola, is an economically important disease in Australia and worldwide. The application of fungicides is the main tool to control this disease. Frequent fungicide applications can lead to the selection of resistant P. viticola populations, which has negative impacts on the management of the disease. Identification of resistance and its prevalence is necessary to inform resistance management strategies. RESULTS: A total of 86 P. viticola isolates were collected between 2017 and 2022 from vineyards in 15 growing regions across Australia for four fungicide groups; phenylamide (PA, group 4), carboxylic acid amide (CAA, group 40), quinone outside inhibitor (QoI, group 11) and quinone outside inhibitor stigmatellin binding type (QoSI, group 45). Decreased phenotypic sensitivity was detected for all four groups, and resistance to metalaxyl‐M (PA) and pyraclostrobin (QoI), was detected. Genetic analysis to detect the G143A (QoI) and G1105S (CAA) mutations using amplicon‐based sequencing was performed for 239 and 65 isolates collected in 2014–2017 and 2017–2022, respectively. G143A was detected in 8% and 52% of isolates, respectively, with strong association to phenotypic resistance. However, G1105S was not detected in any isolates. CONCLUSION: Plasmopara viticola isolates in Australia with resistance to at least two fungicide groups have been detected, therefore it is necessary to adopt resistance management strategies where resistance has been detected. Vineyards should continue to be monitored to improve management strategies for downy mildew. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Garlic is one of the most popular spices in the world and the second most widely cultivated Allium species next to the onion. Garlic production is reduced due to many biotic and abiotic factors, among which white rot disease caused by Stromatinia cepivora (Berk.) Whetzel causes severe yield losses. The study was conducted to evaluate the combined effects of chemical fungicides and garlic varieties on the epidemic development of white rot disease. The experiment was conducted at Chefanen Kebele using three garlic varieties and three chemicals during the 2019 and 2020 seasons. The experimental design was a randomized complete block with three replicates. The application of Apron Star 42, a commercial fungicide containing Thiametoxam 20%, Metalaxyl-M 20% and Difenconazole 2%, significantly reduced the white rot disease on all varieties as compared to the untreated local variety. Bishoftu Nech and MM-98 varieties exhibited fast emergence as compared to the local variety, consequently increasing the yield and yield components of garlic. The application of Apron Star 42, significantly increased yield parameters compared to the untreated control. The significant effect and the negative correlations of days to maturity, growth parameters, yield, and yield components with disease parameters indicated that the white rot disease had a very crucial impact on garlic yield. Application of Apron Star 42 to improved garlic varieties is recommended to reduce the severity of white rot infections and to increase garlic production in the study area. [ABSTRACT FROM AUTHOR]

In wheat and barley, Fusarium head blight is mainly caused by Fusarium graminearum, and its control is based on the agricultural practices of not leaving crop residues in the field, growing phytopathogenic fungi-resistant varieties, biological control, and chemical treatment, including using fungicides. Here, we investigated the antifungal and antimycotoxigenic activities of Massoia essential oil (MEO) and C10 Massoia lactone (C10) on Fusarium graminearum KACC 41047. Because DMSO, which was used as a solvent in this study, exhibited antifungal activity at 5% in a fungal growth medium, it was used in the antifungal and antimycotoxigenic experiments at 0.05%. Three assays were used to investigate the antifungal activities of MEO and C10, which exhibited potent antifungal activity in the agar dilution assay, with complete fungal growth inhibition at 100 mg/L. At 5–50 mg/L, MEO and C10 suppressed deoxynivalenol and 15-acetyl-deoxynivalenol production by >50% by downregulating the Tri10 gene, which expresses trichodiene synthase. MEO and C10 might be potent antifungal agents for F. graminearum control with less toxicological concerns because they are GRAS chemicals. [ABSTRACT FROM AUTHOR]

Triadimefon, a type of triazole systemic fungicide, has been extensively used to control various fungal diseases. However, triadimefon could lead to severe environmental pollution, and even threatens human health. To eliminate triadimefon residues, a triadimefon-degrading bacterial strain TY18 was isolated from a long-term polluted site and was identified as Enterobacter hormaechei. Strain TY18 could grow well in a carbon salt medium with triadimefon as the sole nitrogen source, and could efficiently degrade triadimefon. Under triadimefon stress, a total of 430 differentially expressed genes (DEGs), including 197 up-regulated and 233 down-regulated DEGs, were identified in strain TY18 using transcriptome sequencing (RNA-Seq). Functional classification and enrichment analysis revealed that these DEGs were mainly related to amino acid transport and metabolism, carbohydrate transport and metabolism, small molecule and pyrimidine metabolism. Interestingly, the DEGs encoding monooxygenase and hydrolase activity acting on carbon–nitrogen were highly up-regulated, might be mainly responsible for the metabolism in triadimefon. Our findings in this work suggest that strain E. hormaechei TY18 could efficiently degrade triadimefon for the first time. They provide a great potential to manage triadimefon biodegradation in the environment successfully. [ABSTRACT FROM AUTHOR]

This review will give an insight into the interactions of serum albumins, which are proteins found in the blood, with fungicides. There are molecular interactions between several fungicides and two serum albumin proteins: human serum albumin (HSA) and bovine serum albumin (BSA). The main objective of this review is to through some light on the interactions of the fungicides with serum albumins and to highlight their toxicity level. The interactions of serum albumins with fungicides are complex and can be affected by the properties of the proteins themselves. This review provides valuable insight into the interactions between serum albumins and fungicides, which can help to know the efficacy and mechanism of fungicides and may help in designing new fungicides with low or no toxicity. [ABSTRACT FROM AUTHOR]

[Objective] This study aims to realize the simultaneous determination of fungicide residues in vegetables and fruits. [Methods] A liquid chromatography-tandem quadrupole composite linear ion TRAP-mass spectrometry (LC-QTRAP-MS/MS) method was established for the simultaneous determination of fungicide residues in fruits and vegetables. The samples were salted out with sodium acetate and anhydrous magnesium sulfate in an acetonitrile solution containing 0.1% acetic acid, magnesium sulfate, ethylenediamine-n-propyl silanized silica gel (PSA), octadecylsilane bonded silica gel (HC-C18) and multi-walled carbon nanotubes (MWCNTs) were used for purification. Mass spectrometry was conducted utilizing the enhanced ion scanning mode (MRM-IDA-EPI) and spectral library retrieval technology. The compounds were quantified using an external standard approach, comparing the retention time, ion pairs, and EPI spectral library retrieval. [Results] The 43 kinds of fungicides had a good linear relationship in the mass concentration range of 0.2~5.0 μg/L and 2.5~50.0 μg/L (R2>0.99). The limit of detection (LOD) was 0.1~5.0 μg/kg, and the limit of quantification (LOQ) was 0.4~10.0 μg/kg. The recoveries of the 43 kinds of fungicides were 65.1%～119.8% at three concentration levels, and the relative standard deviations were 0.8%～13.0%. [Conclusion] The established method is rapid, simple, and highly qualitative, and can be used for the screening, confirming and quantitative detection of 43 kinds of fungicides in fruits and vegetables.

Among the vegetables, tomato is one of the economically important vegetables even at the global level. The nutritional and health benefits of tomato are so numerous to the extent that it has gained so much value in Africa due to its low-cost cultivation and contribution to livelihoods. However, Fusarium oxysporum lycopersici (FOL) and drought have been identified as potential threats to tomato production in Nigeria. To manage these challenges, one of the approaches is to identify Nigerian tomato cultivars that can exhibit resistance to FOL and drought. This study therefore investigates four Nigeria tomato cultivars; NGB00714, NGB00715, NGB00725 and NGB00740 to ascertain their resistance attributes to FOL and drought. Prior to their evaluation, Petri - dish seed germination bioassay was used in-vitro to assess the germination potentials of the tomato seeds. NGB00725 had the best germination, followed by NGB00714 and NGB00740 while the least was NGB00715. Using the Petri - dish in-vitro blotter technique, each tomato seed cultivar was separately exposed to FOL spores and FOL metabolites under drought stress induced by polyethyleneglycol (PEG-6000). Cultivar NGB00725, followed by NGB00740 exhibited resistance to FOL under PEG-induced drought stress based on their seed germination potentials. Bioprospecting resistant Nigeria tomato cultivars in this study is an indication of sustainable production of tomatoes in Nigeria against FOL under drought stress.

The production of oak seedlings in intensive crops involves the modification of natural conditions, namely the degree of humidity, through artificial irrigation, which favors the appearance of the pathogen Erysiphe alphitoides, responsible for the Oak Powdery Mildew (OPM) disease. Thus, it is necessary to identify new substances and technologies to control OPM. In this sense, new products approved by the European Union (EU) and Forest Stewardship Council (FSC) were identified, both synthetic and, a great novelty, biological (based on chito-oligosaccharides-oligogalacturonans: COS-OGA). In order to quantify the results, a correlation was made with climatic factors, by sampling data related to temperature and relative humidity with Data Logger devices. The obtained results suggest that OPM has a high virulence in the temperature range of 20 to 30 °C; at a relative humidity above 75%. The data obtained from the field experiments show that the synthetic products controlled OPM with an effectiveness between 70% and 95%, and the biological product behaved almost similarly, between 60% and 90%, which creates high opportunities for environmentally friendly control of forest pathogens.

Dithiocarbamates (DTCs) are nonsystemic, protective fungicides used all over the world to protect fruits, vegetables, and herbs from several fungal infections. Hence, it is very important to detect and quantify their residue in food. In this work, a rapid and sensitive protocol has been validated for the determination of DTCs subclasses, ethylenebisdithiocarbamate (EBDC) and propylenebisdithiocarbamate (PBDC) fungicides in fruits, vegetables, and herbs. The method was based on the decomposition of EBDC and PBDC in an alkaline medium followed by methylation into dimethyl ethylenebisdithiocarbamate (EBDC-dimethyl) and dimethyl propylenebisdithiocarbamate (PBDC-dimethyl), respectively. This was followed by applying citrate buffer acetonitrile-based QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation technique. The method validation was performed according to the European quality control guidelines (SANTE/12682/2019). The precision and trueness of the method were determined from recovery experiments on six replicates of spiked blank samples at 0.01, 0.05, and 0.1 mg/kg for each commodity. The mean recoveries of EBDC-dimethyl and PBDC-dimethyl ranged from 79–119% and 74–120%, respectively. The RSD value for both analytes was in the range of 2–20. The only exception was PBDC-dimethyl in fennel matrix at 0.01 mg/kg. The limit of quantification of the method was 0.01 mg/kg with the exception of PBDC-dimethyl in fennel, which was 0.05 mg/kg. [ABSTRACT FROM AUTHOR]

The rational use of chemical fungicides in chilli pepper (Capsicum annuum L.) for controlling Phytophthora capsici Leo. should include molecules that promote induced systemic resistance in the plant. The study objective was to assess how the application of fungicides, bio-controllers and resistance inducers affects bioactive compounds production and oxidative metabolism in pepper plants when inoculated with P. capsici zoospores. Statistical analyses show significant differences in total flavonoids, total phenols and salicylic acid concentrations in plants treated with Trichoderma harzianum, Acibenzolar-S-Methyl (ASM) and phosphonic acid. In addition, the application of ASM and Bacillus subtilis showed the highest values of antioxidant capacity. On the other hand, ASM application favoured increases in superoxide dismutase and phenyl ammonium lyase activity with values of 4.42 ± 0.016 (units · min−1 · g−1) and 3.90 ± 0.22 U · g−1, respectively. However, hydrogen peroxide production was similar to that of phosphonic acid treatments. Similarly, plants treated with B. subtilis and Metalaxyl-M showed increases in peroxidase enzyme activity with values ranging from 2.86 ± 0.05 to 4.52 ± 0.02 (μmol · [mg protein]−1 · min−1). Likewise, phosphonic acid-treated plants exhibited high catalase enzyme activity with values ranging from 2.38 ± 0.032 μmol H2O2 · min−1 · g−1 to 4.30 ± 0.024 μmol H2O2 · min−1 · g−1. The complementary use of products with biological and resistance-inducing functions could help to mitigate the environmental impacts that occur due to the use of chemical fungicides for controlling P. capsici on chilli pepper. [ABSTRACT FROM AUTHOR]

Over the past decades, concern has been increasing over reported declines in aboveground biodiversity on farmland. In many regions, data on the toxicity of pesticides to honeybees (Apis mellifera), but not wider nontarget arthropod (NTA) data, are required for pesticide registration. In Europe, the effects of pesticides on NTAs and honeybees have been the subject of regulatory risk assessment for more than 30 years, resulting in a large database. Although insecticides may be expected to affect NTA populations, solely identifying insecticidal modes of action for further NTA testing would result in redundancy among low‐risk testing products and may also exclude other modes of action with potential effects in the field. This study assessed whether the honeybee acute risk assessment could provide any indication of the potential impact and recovery time of NTAs in cropped areas at the field scale and, if so, how it might be used in a tiered testing approach. The hazard quotients (HQs; foliar application rate/LR50) were derived for 151 active substances (32% insecticides, 28% fungicides, 38% herbicides, 2% plant growth regulators) for which toxicity data for established EU Tier 1 NTA indicator species (Typhlodromus pyri, Aphidius rhopalosiphi) and application rate data were available. These HQs were compared with published NTA HQ thresholds indicating the time to recovery of NTA populations and communities in field studies (>1 to >12 months). Using the same application rate data, honeybee acute risk quotient (RQ) and HQ were also determined and compared with NTA HQs and honeybee regulatory thresholds. These comparisons demonstrated that, where required, the current regulatory honeybee acute RQ of 0.4 or honeybee HQ of 50 can provide an efficient screening tier to target NTA testing at those products and uses with potential effects in the field where recovery may exceed 12 months. Integr Environ Assess Manag 2024;20:2326–2333. © 2024 SETAC Key Points: Comparison of the 151 nontarget arthropod (NTA) hazard quotients (HQs) with the honeybee acute risk quotients (RQs) and HQs revealed that the current honeybee thresholds (RQ 0.4 or HQ 50) can provide an efficient screening tier to target any NTA testing at those product and use rates with potential effects in the field where recovery may exceed 12 months.Such an approach is also applicable with mixture products and off‐crop, with the relevance of the NTA HQ thresholds potentially being more widely addressed by assessing whether taxa identified in EU field studies encompass the traits of taxa within a region or of a particular species of interest. [ABSTRACT FROM AUTHOR]

BACKGROUND: Peach brown rot caused by Monilinia fructicola severely affects the quality and yield of peach, resulting in large economic losses worldwide. Methyl benzimidazole carbamate (MBC) fungicides and sterol demethylation inhibitor (DMI) fungicides are among the most applied chemical classes used to control the disease but resistance in the target pathogen has made them risky choices. Timely monitoring of resistance to these fungicides in orchards could prevent control failure in practice. RESULTS: In the current study, we developed methods based on recombinase polymerase amplification (RPA) and CRISPR/Cas12a systems to detect MBC and DMI resistance based on the E198A mutation in the β‐tubulin (MfTub2) gene and the presence of the Mona element in the upstream region of the MfCYP51, respectively. For MBC resistance, RPA primers were designed that artificially incorporated PAM sites to facilitate the CRISPR/Cas12a reaction. Subsequently, specific tcrRNAs were designed based on the E198A mutation site. For the detection of the Mona element, we designed RPA primers M‐DMI‐F2/M‐DMI‐R1 that in combination with crRNA1 detected 'Mona' and distinguished resistant from sensitive strains. CONCLUSION: Both methods exhibited high sensitivity and specificity, requiring only a simple isothermal device to obtain results within 1 h at 37 °C. The FQ‐reporter enabled visualization with a handheld UV or white light flashlight. This method was successfully used with purified DNA from lab cultures and crude DNA from symptomatic fruit tissue, highlighting its potential for on‐site detection of resistant strains in orchards. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Utilizing fungicides to protect crops from diseases is an effective method, and novel eco‐friendly plant‐derived fungicides with high efficiency and low toxicity are urgent requirements for sustainable crop protection. RESULT: Two series of rosin‐based fungicides (totally 35) were designed and synthesized. In vitro fungicidal activity revealed that Compound 6a (Co. 6a) effectively inhibited the growth of Valsa mali [median effective concentration (EC50) = 0.627 μg mL−1], and in vivo fungicidal activity suggested a significant protective efficacy of Co. 6a in protecting both apple branches (35.12% to 75.20%) and apples (75.86% to 90.82%). Quantum chemical calculations (via density functional theory) results indicated that the primary active site of Co. 6a lies in its amide structure. Mycelial morphology and physiology were investigated to elucidate the mode‐of‐action of Co. 6a, and suggested that Co. 6a produced significant cell membrane damage, accelerated electrolyte leakage, decreased succinate dehydrogenase (SDH) protein activity, and impaired physiological and biochemical functions, culminating in mycelial mortality. Molecular docking analysis revealed a robust binding energy (ΔE = −7.29 kcal mol−1) between Co. 6a and SDH. Subsequently, biosafety evaluations confirmed the environmentally‐friendly nature of Co. 6a via the zebrafish model, yet toxicological results indicated that Co. 6a at median lethal concentration [LC50(96)] damaged the gills, liver and intestines of zebrafish. CONCLUSION: The above research offers a theoretical foundation for exploiting eco‐friendly rosin‐based fungicidal candidates in sustainable crop protection. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Environmental microorganisms are major contributors to the development and spread of disease. Chemical disinfection can inhibit pathogens and play a preventive role against diseases. In agriculture, prolonging the floating time of chemical pesticides in the air has a positive effect on the control of airborne diseases. However, the interaction of chemical pesticides with airborne pathogens is not yet known. RESULTS: Here, triazole fungicide was transformed into stable smoke aerosols in order to assess the feasibility of employing phase transition release pesticides for air disinfection. The phase transition had a minimal impact on hexaconazole (Hexa) and myclobutanil (Mycl), with their smoke formation rates remaining consistently >90%. In microscopic morphology, triadimenol (Tria) and epoxiconazole (Epox) are solid, and tebuconazole (Tebu), Hexa, Mycl and difenoconazole (Dife) are liquid. Liquid smoke has advantages over solid smoke in the inhibition of environmental pathogens. The floatability and spatial distribution of fungicide aerosol were optimized by the combination of smoke particles with different properties, so that the fungicide aerosol could meet the conditions of practical application. In practical applications, smoke exhibits a gentler deposition process at the target interface compared to spray, along with a more homogeneous distribution of fungicides. Moreover, fungicide smoke demonstrates superior control efficacy and leaves behind lower residual amounts on fruit. CONCLUSION: In conclusion, the implementation of fungicide phase transition as a smoke aerosol offers a viable approach to effectively suppress pathogen aerosols and enhance the control of airborne diseases. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

We studied combined suspension compositions prepared by liquid-phase mechanical treatment based on the fungicides difenoconazole, tebuconazole, imazalil, fludioxanil, thiabendazole, prochloraz, sedoxan and the insecticides thiamethoxam, imidacloprid, plant growth regulators Enershanse, which showed a wide range of biological activity in field conditions. It was established that the main indicators of the quality of the final product - the nature of the grain, the amount of protein and gluten, glassiness, and the quality of gluten - depended on the fungicidal and insecticidal effects on the phytosanitary condition of winter wheat crops. All studied drugs had a protective effect. They contributed to the disinfection of winter wheat seeds from seed and soil pathology and harmful insects of the early period of plant development. It was found that for effective treatment of winter wheat seeds, it is best to use insectofungicidal preparations containing several components of different chemical classes. It was found that pre-sowing treatment of winter wheat seeds with a suspension composition of thiamethoxam + sedaxan + fludioxonil + tebuconazole in the form of Vibranse Integral, suspension concentrate provided the greatest increase in grain yield by 0.49 t/ha (7.3%) with a control yield of 6.74 t/ha. The use of this drug ensures a particularly high protein content in the grain (16.07%) and gluten (36.8%) of the first quality group. We have established diverse positive effects of the drug Vibranse Integral, manifested in enhancing the growth processes of the root system due to the presence of the sedaxane molecule, the purpose of which is aimed at the formation of a healthy and well-developed root system, increasing the stress resistance of plants to abiotic factors, and the manifestation of a good protective effect in relation to soil and seed infections. We determined the lowest, relative to other studied drugs, yield (6.17 t/ha) from the use of a suspension composition of thiamethoxam (262.5 g/l) + difenoconazole (25 g/l) + fludioxonil (25 g/l (Celest Top), but the grain was of high quality. All other seed protectants occupied an intermediate position between the above-mentioned drugs.

Apple leaf blotch, a disease that is caused by the fungus Diplocarpon coronariae (also known as Marssonina coronaria) is a serious apple tree pathogen in areas with optimal conditions for its development. The fungus mainly attacks the leaves of apple trees, resulting in defoliation, which indirectly affects fruit size and color, yield and development of the apple tree shoots. In this experiment, the effectiveness of selected fungicides was tested (Sercadis – active ingredient fluxapyroxad, Belanty – active ingredient mefentrifluconazole, Topas 100 EC – active ingredient penconazole, Delan 700 WDG – active ingredient dithianon, Bellis – active ingredient boscalid and pyraclostrobin, Geoxe 50 WG – active ingredient fludioxonil, Kumulus WG – active ingredient sulphur, Cyflamid 50 EW – active ingredient cyflufenamid) for inhibiting the growth of D. coronariae using the pathogen colony cultivation method on PDA medium with addition of the fungicide. The best results were achieved by fungicides Topas 100 EC, Bellis, Sercadis and Belanty with the effectiveness of 98–100 %. Lower growth reduction was shown by Delan 700 WDG with an efficiency of 68 %. Kumulus WG, Geoxe 50 WG and Cyflamid 50 EW limited the growth of the pathogen with a reduced efficiency of 37, 22 and 15 %, respectively. There was no effect of these fungicides on growth reduction of some fungal strains.

AbstractThe main focus of this study was to create a stable and efficient nanoemulsion (NE) using Callistemon citrinus essential oil (EO). Various factors affecting the NE’s stability were optimized including oil %, Tween 80%, time of sonication, and its accelerated stability was examined. The research also considered the antibacterial, antifungal, and larvicidal effects of the optimized NE (B10). The optimum NE stood out for its stability, featuring a particle size of 33.15 ± 0.32 nm. Analysis via IR spectroscopy confirmed successful EO encapsulation in B10. The formulation remained stable for six months, with B10 showing significantly higher antibacterial and antifungal potency compared to the pure oil. When samples were subjected to tests against Fusarium oxysporum, B10 exhibited a MIC value of 62.5 mg/mL, whereas the pure oil showed a MIC value of 250 mg/mL. This indicates that the B10 formulation was 50 times more effective than the EO. In terms of antibacterial activity against Escherichia coli, the MIC value was 0.256 mg/mL for B10 and 4 mg/mL for the EO. Also, pure oil and B10 displayed larvicidal effects against Chilo suppressalis (Walker) larvae, with B10 eliminating 95.2% of larvae in 48 h. Overall, stable and optimum C. citrinus NE with its strong antimicrobial qualities, shows promise as an effective fungicide and insecticide. [ABSTRACT FROM AUTHOR]

Intensive use of pesticides is among the main drivers of biodiversity loss, especially of insects. Here, field concentrations of chemical synthetic pesticides were measured in soil and carabid beetles in a vineyard (VP) and olive grove (OP), in two consecutive years. The aim was to determine if active ingredients in pesticides applied in the field accumulate in carabids and how this correlates with treatment intensity. Carabids and soil samples were collected at a vineyard and olive grove in Zadar County in Croatia, soil in 2018 and 2019 and carabids in 2019. Both were under integrated pest management (IPM), with a total of 34 pesticides applied, between January and August in the two years of this study. Using LC-MS/MS, a broad range of pesticides, mainly fungicides, was detected in the soil and carabids. In soil samples, boscalid (0.047 mg/kg), mandipropamid (0.08 mg/kg), fluopyram (0.09 mg/kg), cyprodinil (0.09 mg/kg) and tebuconazole (0.13 mg/kg) were detected in the highest amounts. In addition, nine substances were detected in carabids, with valiphenalate (0.048 mg/kg), difenoconazole (0.051 mg/kg) and azoxystrobin (0.064 mg/kg) in the highest concentrations. Bioaccumulation factor (BAF) indicated the accumulation of valiphenalate, metalaxyl-M, spiroxamine and difenoconazole in carabids. Data measured directly in the field revealed the accumulation of pesticides in carabids, which indicates they could be good bioindicators in IPM and contribute to a better understanding of the distribution of pesticides in Mediterranean agroecosystems. [ABSTRACT FROM AUTHOR]

Phthalide, benzoxazole, and chromene are important heterocyclic skeletons with extensive biological activities. In order to develop novel potential antifungal agents, twenty-two benzoxazole/chromene-containing phthalide derivatives were prepared, and their fungicidal activity against nine common plants pathogenic fungi were evaluated in vitro. The EC50 values indicated that compound Z-4b displayed superior antifungal activity against P. oryzae (11.0 μg/mL), F. solani (8.5 μg/mL), P. capsici (27.8 μg/mL), V. mali (3.1 μg/mL) and A. brassicae (4.3 μg/mL) strains, which was more potent than the two commercialized fungicides hymexazol and chlorothalonil. In addition, the structure-activity relationship analysis demonstrated that the combination site of oxazolamide with phthalide has an important effect on antifungal activity. This research offers a potential compound for the development of novel agricultural fungicides. [ABSTRACT FROM AUTHOR]

Background and Objective: The use of pesticides poses serious risks to the health of living organisms. Knowing the type and amount of pesticide use can provide a good information base for managing potential risks from pesticide consumption. This study was carried out with the main objective of determining the types and amounts of pesticides used on agricultural land in East Azarbaijan Province in 2021. Materials and Methods: Information about the pesticides have been gathered and analyzed by referring to the Agricultural Jihad Organization and other relevant authorities. Calculations related to the amount of pesticides used per unit area were made using the total area of agricultural lands in the province. Results: Considering the frequency, 403 kinds of pesticides are used in the following order: Herbicides > Insecticides > Fungicides > Acaricides > Others > Disinfectants. Consdidering total consumption of 2873730 kg pesticides, the order based on the amount is: Insecticides > Herbicide > Fungicides > Miscellaneous > Acaricides and Disinfectants based on the amount. The total ratio of pesticides used to pesticides distributed through the official (government) channel is 2.51. The minimum, maximum, and mean consumption values in counties are 0.4, 21.4, and 4.21 ± 5.33 kg/ha, respectively, and for province is 2.38 kg/ha. There is a correlation between the amount of pesticide applied and the number of farmers and traders. Conclusion: The consumption of pesticides in the province is higher than the world average. Appropriate management of pesticides is required from the viewpoints of environment and health protection. [ABSTRACT FROM AUTHOR]

The dieback disease is caused by the phytopathogen Lasiodiplodia theobromae that affects farmer's production; it is characterized by its ability to survive through pycnidia and chlamydospores in soil and crop residues, it spreads to plant tissues to remain endophytic until the host crop becomes vulnerable by mechanical damage or nutrient deficiency leading to death of young branches, mummification and fruit rot. Due to the persistent mode of L. theobromae, the research focused on the simultaneous depuration of strains of the phytopathogen isolated from banana and raspberry with the objective of detecting the mycelial growth rate against fungicides of different mode of action, establishing by means of a toxicity scale at one of the concentrations 10; 1; 0,1; 0,01 and 0,001 µg mL-1 as efficient with propiconazole, mancozeb, iprodione, difenoconazole and cyproconazole, respectively in their order. There was 100% growth inhibition with propiconazole and difenoconazole at a concentration of 10 µg mL-1 that allows them to be effective fungicides in the control of the phytopathogen, while mancozeb, iprodione and cyproconazole were harmless to L. theobromae, because they allowed its mycelial growth in the research. [ABSTRACT FROM AUTHOR]

Background: Mold contamination in post‐harvest grain storage degrades grain quality and produces mycotoxins, causing economic losses and health issues. This study evaluated the inhibitory effects of six essential oils (cinnamon, clove, eugenol, orange terpenes, oregano, and thyme oil) on total and specific mold genera growth using potato dextrose agar (PDA) and selective media plates, respectively, at different concentrations of EOs (0–0.8 mg/mL). The antifungal index (AI) of each treatment were measured after 7 days incubation at 22°C. The fungicidal activity of EOs in stored organic corn grains was tested using a simulated fumigation method, and the aflatoxin contents in the corn grains were determined biweekly for 6 weeks. Results: Results indicate that the tested EOs, except orange terpenes, significantly inhibited mold growth. Overall, eugenol demonstrated the highest effectiveness against total mold growth with cinnamon oil following closely behind. The cinnamon oil also consistently showed highest AI and lowest IC50 (0.065 mg/mL) against the growth of Aspergillus and Penicillium followed by clove oil with IC50 being 0.12 mg/mL. The Fusarium spp. was more sensitive to EOs, particularly cinnamon oil (IC50 = 0.006 mg/mL), and eugenol and oregano oil (IC50 = 0.01 mg/mL). In the simulated fumigation tests, cinnamon, oregano, and thyme oils at 0.05 mL/25 g corn significantly inhibited the mold growth and aflatoxin production at water activity 0.85, and temperature 25 and 35°C over a period of 42 days storage. Conclusion: The EOs tested in this study except orange terpenes can potentially serve as alternatives to toxic synthetic fungicides/fumigants for organic corn grain protection during storage. [ABSTRACT FROM AUTHOR]

• Twenty kinds of AFs in the lower reaches of the Yangtze River were analyzed. • Spatiotemporal distribution and fate in the urban water cycle. • Assessment of ecological risk and dietary exposure. Azole fungicides (AFs) play an important role in the prevention and treatment of fungal diseases in agricultural crops. However, limited studies are addressing the fate and ecological risk of AFs in the urban water cycle at a large watershed scale. To address this gap, we investigated the spatiotemporal distribution and ecological risk of twenty AFs in the lower reaches of the Yangtze River across four seasons. Carbendazim (CBA), tebuconazole (TBA), tricyclazole (TCA), and propiconazole (PPA) were found to be the dominant compounds. Their highest concentrations were measured in January (188.3 ng/L), and November (2197.1 ng/L), July (162.0 ng/L), and November (1801.9 ng/L), respectively. The comparison between wastewater treatment plants (WWTPs) effluents and surface water suggested that industrial WWTPs are major sources of AFs in the Yangtze River. In particular, TBA and PPA were found to be the most recalcitrant AFs in industrial WWTPs, while difenoconazole (DFA) was found to be the most potent pollutant in municipal WWTPs, with an average removal rate of less than 60%. The average risk quotient (RQ) for the entire AFs was 6.45 in the fall, which was higher than in January (0.98), April (0.61), and July (0.40). This indicates that AFs in surface water posed higher environmental risks during the dry season. Additionally, the exposure risk of AFs via drinking water for sensitive populations deserves more attention. This study provides benchmark data on the occurrence of AFs in the lower reaches of the Yangtze River, and offers suggestions for better reduction of AFs. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Chickpea (Cicer arietinum L.) is the most important leguminous crop around the world. Fusarium wilt incited by Fusarium oxysporum f. sp. ciceris is a major biotic constraint in chickpea production. The present investigation was undertaken to evaluate the efficacy of plant extracts, fungicides and bio-agents against Fusarium oxysporum f. sp. ciceris under in vitro and field conditions. Methods: Plant extracts and fungicides were evaluated using poison food technique while antagonistic activity of bio-agents was studied using dual culture technique under in vitro conditions. Field trials were conducted to evaluate the efficacy of different plant extracts, fungicides and bio-agents against Fusarium wilt at Experimental Area of Plant Pathology, CCS HAU, Hisar. Result: Among thirteen plant extracts evaluated in vitro, neem leaves extract was found to be the most effective in inhibiting mycelial growth of F. oxysporum f. sp. ciceris followed by datura leaves’ and garlic cloves’ extract which were statistically at par. Out of six plant extracts tested against Fusarium wilt under field conditions, seed treatment with extracts of neem and datura leaves at 10% concentration were most effective and curtailed the wilt incidence by 39.02 and 34.14% along with 7.55 and 6.83% enhanced seed yield. Among fungicides, carbendazim 50 WP was the most toxic fungicide in restricting colony diameter of the pathogen with the least EC50 and EC90 values of 1.28 and 15.24 ppm a.i. followed by azoxystrobin 23 SC with corresponding values of 1.57 and 49.16 ppm a.i., respectively. Seed treatment with carbendazim 50 WP and azoxystrobin 23 SC were superior over other treatments and provided 88.41 and 85.98% reduction in disease incidence along with 12.85 and 10.99% higher seed yield over control. Among the bio-agents tested, T. viride and T. harzianum gave the best results in suppressing the pathogen growth in vitro and in minimizing the disease incidence coupled with improvement in seed yield under field conditions. The present study has provided chemical and non-chemical measures for integrated management of chickpea wilt [ABSTRACT FROM AUTHOR]

We evaluated the effects of fungicides on strawberry powdery mildew (PM) fungus, Podosphaera aphanis, using an electrostatic technique. Thirty-six fungicides were sprayed on single colonies of P. aphanis on leaves of strawberry seedlings (Fragaria × ananassa Duchesne ex Rozier). Colony development varied depending on the tested fungicides. Particularly, pyraziflumid, triflumizole, triforine, polyoxin, sodium hydrogen carbonate + copper wettable powder, and flutianil + mepanipyrim were highly effective for reducing colony development. P. aphanis colonies were histochemically stained to observe the morphological characteristics of fungal cells forming normal and abnormal conidiophores. Abnormal conidiophores were classified into seven types based on their morphological and cytological characteristics. Finally, asexual conidia were collected from single P. aphanis colonies on the leaves spray-treated with fungicides using a dielectrically polarized insulator plate (electrostatic spore collector); conidia attracted to the insulator plates were counted using a high-fidelity digital microscope. Most tested fungicides highly inhibited the production and/or germination of asexual conidia. The germination of asexual conidia was observed only in thiophanate-methyl (methyl benzimidazole carbamates fungicides; MBC fungicides) and azoxystrobin (quinone outside inhibitors; QoI fungicides). Assessing with the electrostatic technique, we clarified that P. aphanis has developed resistance to both thiophanate-methyl and azoxystrobin. Thus, the methodological assessment analyzing the colony development and the number of conidia released from single colonies will be helpful information for screening effective fungicides. [ABSTRACT FROM AUTHOR]

Late blight (LB) caused by Phytophthora infestans (Mont.) de Bary, is one of the most destructive diseases of potato and tomato worldwide. Globally, application of fungicide is an effective approach for potato LB management. Isolates of P. infestans were collected from different fields in Egypt and characterized using microsatellite markers and mitcondrial DNA. Twelve fungicides were applied in vitro to test their control P. infestans isolates. Nine potato cultivars were evaluated under artificial inoculation. Field trials were conducted to evaluate the efficacy of applied fungicides to LB management and potato productivity at El-Behera governorate in two seasons. Our results revealed that collected isolates of P. infestans were A1 mating type, 23_A1 clonal lineage and Ia/IR1 mitcondrial DNA. Furthermore, potato cultivar Burren was highly resistant and recorded the lowest area under disease progress curve (AUDPC). On the other hand, cultivars Alaska, Spunta, Lady Rosita and Mondial were highly susceptible and revealed the highest AUDPC values. In vitro, all fungicide applications inhibited linear growth of P. infestans isolates (EG-Pi1 and EG-Pi2). For field trial, Equation-Pro, and Consonto were the most effective fungicides in respect of LB management where lowest disease severity and AUDPC were recorded in both prophylactically and curatively during two seasons. Moreover, potato tuber production significantly increased with Equation -- Pro application. The results of this study provided crucial information for potato breeding programs and crop improvement as well as successful management strategy for late blight challenge. [ABSTRACT FROM AUTHOR]

One of the most common fungicides, Thiophanate-methyl (TM), has been extensively used to prevent fusarium wilt disease. Understanding the kinetic behavior of the TM-fungicide in the greenhouse soil was aimed at the current research. The findings demonstrated that TMfungicide goes through the pseudo-first-order model (PFO), which results in a rate constant K= 0.421 minutes-1. As a result, TM-fungicide needs 16.46 minutes-1 to degrade 50% of the initial concentration. The power function for TM-fungicide ranged from -1.826 to 0.0360 minutes-1, and the distribution coefficient was 6.5 mL g-1. Regarding the adsorption of Langmuir and Freundlich, TM-fungicide is more fitting to the Freundlich with the aF = 25.73 and the bF = 0.078 compared to the Langmuir model. The TM-fungicide starts to release to the soil after 4-5 hours, achieving extensive, effective control of the soil pests, Moreover, TM-fungicide is highly mobile in the soil based on the current conditions. [ABSTRACT FROM AUTHOR]

Propineb is a widely used protective fungicide in farmland. To investigate the effects of propineb on cadmium (Cd) accumulation and the physiological characteristics of wheat seedlings under Cd stress, we performed a hydroponic experiment with artificially added Cd. The results indicated that the application of propineb leads to a decrease in Cd accumulation in the shoots of wheat. During the low-Cd treatment experiment, propineb caused Cd to transfer from the soluble component to the cell wall. In terms of the chemical morphological distribution of Cd in wheat seedlings, propineb reduced the proportions of ethanol extracted state and deionized water extracted state, whereas the proportions of acetic acid extracted state and hydrochloric acid extracted state increased. The photosynthetic rate of wheat seedlings significantly increased, but there was no significant effect on the chlorophyll content. Foliar application of propineb increased the O2− clearance rate and hydrogen peroxide content in the wheat. However, the catalase content decreased. This study indicates that the application of propineb could decrease Cd accumulation in wheat seedlings and partially improve the physiological functions of plants. This study provides useful information for studying the effects of pesticides on Cd accumulation in crops and the physiological characteristics of Cd stress. [ABSTRACT FROM AUTHOR]