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Ridomil Gold SL (45.3% a.i. mefenoxam) is a widely used chemical fungicide for the control of oomycetes. However, its impact on fungal communities remains unexplored. Therefore, the goal of this study was to examine the effects of mefenoxam on the temporal dynamics of fungal taxonomic and functional diversities during carrot cultivation under four treatment groups: mefenoxam application with and without Pythium inoculation, and untreated control groups with and without Pythium inoculation. Our in vitro sensitivity assay showed that the maximum recommended concentration of mefenoxam, 0.24 ppm, did not suppress the mycelial growth of P. irregulare. At 100 ppm, mycelial growth was only reduced by 11.4%, indicating that the isolate was resistant to mefenoxam. MiSeq sequencing data revealed transient taxonomic variations among treatments 2 weeks post-treatment. Mortierella dominated the fungal community in the mefenoxam-Pythium combination treatment, as confirmed through PCR using our newly designed Mortierella-specific primers. Conversely, mefenoxam-Pythium combination had adverse effects on Penicillium, Trichoderma, and Fusarium, and decrease the overall alpha diversity. However, these compositional changes gradually reverted to those observed in the control by the 12th week. The predicted ecological functions of fungal communities in all Pythium and mefenoxam treatments shifted, leading to a decrease in symbiotrophs and plant pathogen functional groups. Moreover, the community-level physiological profiling approach, utilizing 96-well Biolog FF microplates, showed discernible variations in the utilization of 95 diverse carbon sources among the treatments. Notably, arbutin, L-arabinose, Tween 80, and succinamic acid demonstrated a strong positive association with Mortierella. Our findings demonstrate that a single application of mefenoxam at its recommended rate triggers substantial taxonomic and functional shifts in the soil fungal community. Considering this impact, the conventional agricultural practice of repeated mefenoxam application is likely to exert considerable shifts on the soil ecosystem that may affect agricultural sustainability.

[Objective] To screen out the effective pesticides against Colletotrichum gloeosporioide. [Method]Seven fungicides were selected to carry out toxicity test and field efficacy test. [Result]The toxicity test results showed that the 4 d-EC50 of 35% Difenoconazole·Pyraclostrobin SC, 30% Pyraclostrobin·Tebuconazole SC, 30% Pyraclostrobin·Flusilazole EC, 40% Difenoconazole SC, 25% Pyraclostrobin SC, 430 g / L Tebuconazole SC and 40% Flusilazole EC against Colletotrichum gloeosporioide were 0. 194 0, 0. 078 8, 0. 097 8, 0. 445 0, 0. 218 0, 0. 165 0, and 0. 146 0 mg / L, respectively;in the field efficacy test, the control effect of 7 pesticides on Colletotrichum gloeosporioide of fig leaves was as follows:30% Pyraclostrobin·Tebuconazole SC had the best control effect at 2 000 times, with a control effect of 92. 76%±2. 96%. 30% Pyraclostrobin·Flusilazole EC had the second best control effect at 2 000 times, with a control effect of 89. 54%±2. 41%. There was no significant difference between the two. The control effect of other pesticides at 2 000 times was over 80%. 30% Pyraclostrobin·Tebuconazole SC had a control effect of over 80% at 3 000 times, while the control effect of the remaining treatments was poor. The control results of 7 pesticides on Colletotrichum gloeosporioide of fig fruit were as follows:30% Pyraclostrobin·Tebuconazole SC had the best control effect at 2 000 times liquid, reaching 86. 22% ± 3. 87%, 30% Pyraclostrobin·Flusilazole EC had a control effect of 83. 69% ± 1. 59% at 2 000 times liquid, 430 g / L Tebuconazole SC had a control effect of 81. 68% ± 2. 01% at 2 000 times liquid, and the control effect in other treatments was lower than 80%. [Conclusion]The results showed that the 30% Pyraclostrobin·Tebuconazole SC and 30% Pyraclostrobin·Flusilazole EC had good control effects on fig anthracnose at a concentration of 2 000 times, and could be extended to the prevention and control of anthracnose in fig planting areas in Guangxi region. [ABSTRACT FROM AUTHOR]

AbstractSupervised field trial studies were conducted to understand dissipation kinetics and harvest time residues of a combination product of fluxapyroxad and pyraclostrobin in cumin plant/leaves and seeds at different locations in India. The results showed initial accumulation of fluxapyroxad at the levels of 15.4 and 20.2 mg kg−1 and pyraclostrobin at the level of 21.2 and 33.4 mg kg−1 in cumin leaves/plant in Anand, Gujarat. Fluxapyroxad and pyraclostrobin followed zero-order and first-order dissipation kinetics in cumin plant/leaves samples respectively. The residues translocated to cumin seeds. As the hazard quotient (HQ) was <1 in all cases consumer health risk may be negligible. [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]

The objective of this study was to determine the best method to establish optimal timing of fungicide applications on corn (Zea mays), soybean (Glycine max), and bean plants (Phaseolus vulgaris), by comparing results based on the calendar versus agrometeorological data. The experimental design was arranged in randomised blocks with three treatments and eight repetitions. Treatments consisted of control (without application of fungicides), application of fungicides based on the calendar (after establishing the need for chemical control, sprays occurring at intervals of 15 days), or by indication of the AgroDetecta™ programme (based on agrometeorological data). The variables evaluated were: disease incidence and severity, area under the disease progress curve (AUDPC), income components, and economic return. Among the integrated disease management tools investigated, it was concluded that chemical control improves crop health and yield for corn, soybean, and bean plants, especially when timing of treatment application is based on the calendar. The programme AgroDetecta™ showed promise as a decision-making tool for the best timing to spray, but requires adjustments for commercial use. [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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

This work aims at improving the proven protocol for doubled haploid production in wheat. This procedure has some deficits, for example, microbial infection of ears as well as of the nutrient culture medium. In the present study, the potential effect of sterilization by detached tiller culture fungicides of ears as well as of nutrient medium to control microbial infection, and its effect on the formation of caryopses and embryos (CFF, EFF) was studied. In a further experiment, the UV‐light was used as physical sterilant for the nutrient medium. All of the fungicides and their concentrations studied were found to be effective to control infection on ears except the concentration 0.05% tilt. 0.1% tilt gave the highest CFF (79.5%) followed by 0.1% Bayleton (78.0%). The lowest CFF was recorded in control treatment (48.8%). Among Bavistin treatments, the 0.2% Bavistin gave maximum CFF (68.5%) as well as EFF (29.1%) followed by 0.1% Bavistin (64.9%, 23.7%). The higher concentration of tilt (0.2%) showed detrimental effects on EFF (17.5%). Bavistin in tiller culture nutrient medium reduced infection in medium and was shown to improve CFF and EFF (67.4%, 29.8%). [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]

Fusarium root rot is usually classified as an extremely destructive soilborne disease. From 2020 to 2021, Fusarium root rot was observed in production areas and seriously affected the yield and quality of Scutellaria baicalensis in Shanxi Province, China. Based on morphological characteristics and combined analysis of the internal transcribed spacer region of ribosomal DNA and translation elongation factor 1 -alpha sequences. 68 Fusarium isolates obtained in this work were identified as E oxysporum (52.94%), F. acuminatum (20.59%), F. solani (16.17%). F. proliferatum (5.88%), F. incarnation (2.94%), and F. brachygibbosum (1.47%). In the pathogenicity tests, all Fusarium isolates could infect S. baicalensis roots, presenting different pathogenic ability. Among these isolates, F. oxysporum was found to have the highest virulence on S. baicalensis roots, followed by F. acuminatum, F. solani, F. proliferatum. F. brachygibbosum, and F. incarnation. According to fungicide sensitivity tests, Fusarium isolates were more sensitive to fludioxonil and difenoconazole, followed by carbendazim, thiophanate-methyl, and hymexazol. In brief, this is the first report of Fusarium species (F. oxysporum, F. acuminatum, F. solani, F. proliferatum, F. incamarum, and F. brachygibbosum) as causal agents of root rot of S', baicalensis in Shanxi Province, China. The fungicide sensitivity results will be helpful for formulating management strategies of baicalensis root rot. [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]

The conclusions of the EFSA following the peer review of the initial risk assessment carried out by the competent authority of the rapporteur Member State, Spain, for the pesticide active substance difenoconazole are reported. The context of the peer review was that requested by the European Commission following the submission and evaluation of confirmatory information with regard to the consumer risk assessment. The conclusions were reached on the basis of the evaluation of the representative uses of difenoconazole as a fungicide on pome fruit, carrot, wheat, barley, triticale, rye and oats. The reliable endpoints concluded as being appropriate for use in regulatory risk assessment, derived from the available studies and/or literature in the dossier peer reviewed, are presented. Concerns were not identified. [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]

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]

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]

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]

Cymoxanil (CYM) is a widely used synthetic acetamide fungicide, but its biochemical mode of action remains elusive. Since CYM inhibits cell growth, biomass production, and respiration in Saccharomyces cerevisiae, we used this model to characterize the effect of CYM on mitochondria. We found it inhibits oxygen consumption in both whole cells and isolated mitochondria, specifically inhibiting cytochrome c oxidase (CcO) activity during oxidative phosphorylation. Based on molecular docking, we propose that CYM blocks the interaction of cytochrome c with CcO, hampering electron transfer and inhibiting CcO catalytic activity. Although other targets cannot be excluded, our data offer valuable insights into the mode of action of CYM that will be instrumental in driving informed management of the use of this fungicide. [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]

Sorghum northern anthracnose is a leaf disease affecting sorghum, which results in plant death and substantial yield loss. This study aimed to effectively understand the disease, clarify its biological characteristics, and evaluate the resistance of germplasm resources. A field sample was collected to isolate and purify the pathogen. The pathogen, identified as Kabatiella zeae Narita et Hiratsuka using both morphological and molecular techniques, was further confirmed as the causative agent of northern anthracnose of sorghum following Robert Koch's principles. The results revealed the optimal culture temperature to be 25 °C, preferred dark culture conditions, and the best growth on potato glucose agar medium with sucrose and L-leucine as the optimal carbon and nitrogen sources, respectively. A total of 138 sorghum germplasm resources were inoculated and evaluated using the isolated pathogen, with 20 lines (14.49%) exhibiting high resistance, 18 lines (13.04%) showing disease resistance, 27 lines (19.57%) demonstrating medium resistance, 37 lines (26.81%) being susceptible, and 36 lines (26.09%) classified as highly susceptible. The indoor fungicide screening was conducted through pathogen medium application, and enilconazole, pyraclostrobin, methylthiophanate, and flusilazole were screened for the best fungicide inhibition with a 100% inhibition rate compared with the control. This study provides reference for field pharmaceutical control in sorghum production. [ABSTRACT FROM AUTHOR]

Fungicides are pesticides that are frequently used in agriculture because of their action against fungal diseases. However, the widespread application of pesticides around the world raises environmental and public health concerns, since these compounds are toxic and can pose risks to ecosystems and human health. The aim of this study was to evaluate the phytotoxic, cytogenotoxic, and biochemical effects of azoxystrobin and carbendazim on Lactuca sativa L. and their physiological effects on Phaseolus vulgaris L. by analyzing the cell cycle and chromosomal and nuclear alterations in L. sativa; the biochemical effects of azoxystrobin and carbendazim on Phaseolus vulgaris L. and their physiological effects on Phaseolus vulgaris L. by analyzing the cell cycle and chromosomal and nuclear alterations in L. sativa; the biochemical effects by analyzing the activity of antioxidant enzymes in L. sativa; and the physiological effects by analyzing chlorophyll content and chlorophyll a fluorescence in P. vulgaris. It was observed that both fungicides were phytotoxic and cytotoxic, reducing root growth and the mitotic index, cytogenotoxic, increasing the occurrence of chromosomal alterations, as well as inducing oxidative stress and an increase in chlorophyll fluorescence emission and altered energy absorption in the plants used as a test system. In view of this, studies such as the one presented here indicate that the use of pesticides, even in small quantities, can lead to damage to the metabolism of plant organisms. [ABSTRACT FROM AUTHOR]

Downy mildew is a production limiting factor for Brazil's main onion producing region. In the present study we tested two management strategies, namely the utilization of a resistant cultivar and the implementation of a disease alert system. Our objective was to mitigate the frequency of systemic fungicide applications while concurrently sustaining optimal yield levels. By carrying out fungicide sprays only when the alert system indicated a severe risk and using the cultivar "SCS379 Robusta", it was possible to reduce the number of sprays from 11 (calendar) to 5 (alert system), maintaining statistically similar yields (32.58 tonnes/ha – calendar; and 30.76 tonnes/ha – alert system). The reduction in spray applications using an integrated management strategy reduced the cost of spraying by more than half from BRL 0.069/Kg to BRL 0.033/Kg. This study demonstrates that implementation of an integrated management strategy can reduce chemical use and cost without compromising the protection of onion using alert system and more susceptible varieties. [ABSTRACT FROM AUTHOR]

Background: Cotton (Gossypium hirsutum L.), adapted to tropical and subtropical regions of the world, is highly sensitive to low temperatures throughout its life cycle. The objective of this study was to evaluate the mitigating effects of different doses of animal-derived (0.25%, 0.50%, and 1.00% Isabion®), seaweed-based (0.165%, 0.330%, and 0.660% Proton®) biostimulants, as well as a copper (Cu)-containing fungicide application, on cotton cultivar Lazer seedlings at the four true leaves (V4) stage. The plants were exposed to a low temperature of 5 °C for 48 h, and the changes in morphological (seedling fresh and dry weight, plant height, and stem diameter) and physiological parameters (leaf temperature, chlorophyll content, relative water content, electrolyte leakage, and relative injury) were examined. Results: The results revealed that chilling stress reduced plant growth, while biostimulants helped protect the plants and overcome the adverse effects of chilling. Under chilling stress, there was a considerable reduction in seedling fresh weight (SFW), seedling dry weight (SDW), plant height (PH), stem diameter (SD), leaf temperature (LT), and relative water content (RWC). Cotton seedlings treated with the animal-derived biostimulants showed significantly enhanced SFW, SDW, PH, SD, LT, chlorophyll content (Chl), electrolyte leakage (EL), and relative injury (RI), although there were no positive changes in RWC. No significant differences in the morphological traits were observed among the doses of seaweed biostimulants. For SDW, PH, EL, and RI, the best results were obtained with the application of a fungicide containing copper. Conclusion: These results show the efficiency of the biostimulant and fungicide treatments in mitigating low-temperature stress in cotton seedlings. Applying a copper-containing fungicide to cotton seedlings helped to counteract the negative effects of low-temperature stress and to protect the plants from damage by maintaining electrolyte balance. Among the biostimulant applications, all levels of animal-derived biostimulant applications, as well as the 0.660% level of the seaweed-derived biostimulant, led to increased tolerance of cotton plants to chilling stress. [ABSTRACT FROM AUTHOR]

BACKGROUND: Peanut southern blight disease, caused by Sclerotium rolfsii, is a destructive soil‐borne fungal disease. The current control measures, which mainly employ succinate dehydrogenase inhibitors, are prone to resistance and toxicity to non‐target organisms. As a result, it is necessary to explore the potential of eco‐friendly fungicides for this disease. RESULTS: Fourteen novel phthalide compounds incorporating amino acid moieties were designed and synthesized. The in vitro activity of analog A1 [half maximal effective concentration (EC50) = 332.21 mg L−1] was slightly lower than that of polyoxin (EC50 = 284.32 mg L−1). It was observed that on the seventh day, the curative activity of A1 at a concentration of 600.00 mg L−1 was 57.75%, while the curative activity of polyoxin at a concentration of 300.00 mg L−1 was 42.55%. These results suggested that our compound exhibited in vivo activity. Peanut plants treated with A1 showed significant agronomic improvements compared to the untreated control. Several compounds in this series exhibited superior root absorption and conduction in comparison to the endothermic fungicide thifluzamide. The growth promotion and absorption‐conduction experiments demonstrated the reason for the superior in vivo activity of the target compound. Cytotoxic assays have demonstrated that this series of targeted compounds exhibit low toxicity levels toward human lo2 liver cells. CONCLUSION: Our results provide a new strategy for the design and synthesis of novel green compounds. Furthermore, the target compound A1 can serve as a lead for further development of green fungicides. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

To ensure ongoing sustainability, the modern agrochemical industry is faced with enormous challenges. These arise from provision of high‐quality food to increasing water use and environmental impact as well as a growing world population. The loss of previous agrochemicals due to consumer perception, changing grower needs and ever‐changing regulatory requirements is higher than the number of active ingredients that are being introduced into the crop protection market. Therefore, the development of novel agrochemicals is essential to provide improved efficacy and environmental profiles. In this context, the introduction of fluorine atoms and fluorine‐containing motifs into a molecule is an important method to influence its physicochemical properties. These include, for example, small difluoro‐ and trifluoromethyl, or trifluoromethoxy groups at aryl or heterocyclic aryl moieties but also fragments like 2,2,2‐trifluoroethoxycarbonyl, trifluoromethylsulfonyl, trifluoroacetyl, as well as the so far unusal rest like heptafluoro‐iso‐propyl. This review gives an overview of recent developments of fluorine‐containing pesticides launched over the past 7 years and describes a selection of current fluorine‐containing development candidates. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

As an evergreen shrub, Euonymus japonicus plays a crucial role in urban landscape construction, and its growth is affected by severe foliar anthracnose caused by Colletotrichum spp. However, the biodiversity of Colletotrichum species associated with anthracnose on E. japonicus remains undetermined. This study involved a two-year collection of E. japonicus leaf samples with typical anthracnose symptoms from 9 districts in Beijing, China. A total of 194 Colletotrichum isolates were obtained, and eight Colletotrichum species were subsequently identified using morphological characteristics and molecular identification with the ACT, GADPH, CHS, TUB2, and CAL genes, as well as the rDNA-ITS region. These species included Colletotrichum aenigma, C. fructicola, C. gloeosporioides, C. grossum, C. hebeiense, C. karstii, C. siamense, and C. theobromicola with C. siamense being the most prevalent (57%), followed by C. aenigma and C. theobromicola. Furthermore, C. fructicola, C. grossum and C. hebeiense are reported for the first time as causal agents of anthracnose on E. japonicus worldwide, and C. karstii is newly reported to be associated with E. japonicus anthracnose in China. Pathogenicity tests revealed that all tested isolates exhibited pathogenicity in the presence of wounds, emphasizing the need to avoid artificial or mechanical wounds to prevent infection in E. japonicus management. The EC50 values of five fungicides, namely difenoconazole, flusilazole, tebuconazole, hexaconazole, and prochloraz, were found to be less than 10 mg/L, indicating their strong potential for application. Notably, the EC50 of prochloraz was less than 0.05 mg/L for C. theobromicola. These findings offer valuable insights for the management of anthracnose on E. japonicus. [ABSTRACT FROM AUTHOR]

Fungal diseases cause substantial loss to agricultural crops, affecting both quantities and quality. Although several methods are used for preventing disease incidence, fungicides remain crucial for higher yields and better quality. But in the past, the efficacy of several fungicides has decreased due to increased cases of fungicide resistant. In our pursuit of new effective fungicides, we synthesised a series of twenty 2-Indazol-1-yl-chromen-4-one derivatives (6a- 6t). The characterization of synthesized compounds was performed by several spectroscopic methods including Infrared, Nuclear Magnetic Resonance (¹H and 13C) and HRMS. Out of 20 synthesised compounds, 19 (6b- 6t) were found to be novel. All synthesised indazolylchromones showed very good antifungal activity against Sclerotium rolfsii and Fusarium oxysporum. Among the tested compounds, 6t and 6f exhibited very good fungicidal activity against S. rolfsii with an ED50 of 10.10 mg L-1 and 16.18 mg L[sup -1], respectively. In case of Fusarium oxysporum compound 6f displayed good' activity with an ED50 value of 27.82 mg L-1. Molecular docking study was done to predict the binding sites of most active compounds, 6t and 6f with Cytochrome P450 14alpha -sterol demethylase (CYP51) enzyme using molsoft software. The acute toxicity predictions the of synthesized compounds for fish (LC50,96 Hr), daphnid (LC50, 48 Hr) and green algae (EC50, 96Hr) and the chronic toxicity predictions (ChV) were assessed using Ecological Structure Activity Relationship (ECOSAR) model. As per ECOSAR prediction, all the chemicals are inside AD and not missing predictions. [ABSTRACT FROM AUTHOR]

AbstractFusarium graminearum is the most important pathogen of maize and winter wheat in Canada, resulting in yield loss and mycotoxin contamination. Fungicides are essential to manage F. graminearum in cereal crops. Until pydiflumetofen became commercial, the only available fungicides were triazoles, limiting the potential to manage fungicide resistance. Fusarium graminearum isolates were surveyed from wheat, grain maize and overwintering maize stalks in southern Ontario. Chemotype and the baseline sensitivity to pydiflumetofen were determined in addition to sensitivity to common fungicides used to control F. graminearum. Fusarium graminearum has several strains producing different trichothecenes called chemotypes. In Ontario, 73.3% of the F. graminearum isolates were 3ANX chemotypes producing 7α-hydroxy, 15-deacetylcalonectrin, in addition to 15-acetyldeoxynivalenol and deoxynivalenol; the remaining isolates were 15ADON chemotypes producing only 15-acetyldeoxynivalenol and deoxynivalenol. Chemotype was not affected by isolate source (wheat grain, maize grain, maize stalks) nor by location. All isolates were sensitive to pydiflumetofen and fungicide products containing pydiflumetofen. The mean EC50 for isolates exposed to pydiflumetofen was 0.05 µg mL−1 (range 0.01–0.10 µg mL−1). The mean EC50 for isolates exposed to Miravis®Ace (containing pydiflumetofen and propiconazole), Miravis®Neo 300SE (containing pydiflumetofen, azoxystrobin and propiconazole), Caramba® (containing metconazole), Proline® (containing prothioconazole) and Prosaro (containing prothioconazole and tebuconazole) was 0.06, 0.13, 0.18, 0.05, 3.75 and 0.30 µg mL−1, respectively. These data will be useful in monitoring the development of fungicide resistance. [ABSTRACT FROM AUTHOR]

The practical utilization rates of conventional pesticide formulations by target organisms are very low, which results in the pollution of ecological environments and the formation of pesticide residues in agricultural products. Water-based nanopesticide formulations could become alternative and effective formulations to eventually resolve the main issues of conventional pesticide formulations. In this feature article, we describe the design concept of smart (stimuli-responsive) controlled-release nanopesticides, which are created toward hierarchical targets (pests, pathogens, and foliage) in response to multidimensional stimuli from physiological and environmental factors (such as sunlight) of target organisms and plants, for achieving enhanced insecticidal and fungicidal efficacies. The pore sizes and functionalities of metal–organic frameworks (MOFs) can be fine-tuned through the choice of metal-containing units and organic ligands. Tailor-made MOF nanoparticles with large microporous or mesoporous sizes, as well as good biocompatibility and high thermal, mechanical, and chemical durabilities, are used to load pesticides within these pores followed by coating of plant polyphenols and natural polymers for stimuli-responsive controlled pesticide release. This feature article highlights our works on smart controlled-release MOF-based nanopesticides and also includes related works from other laboratories. The future challenges and promising prospects of smart controlled-release MOF-based nanopesticides are also discussed. [ABSTRACT FROM AUTHOR]

Naturally occurring substances and their derivatives function as vital resources for pesticides that can be used in fields, such as insecticide production and fungicide development. As a botanical entity displaying multifaceted biological functions, wormwood has received thorough scrutiny across multiple sectors. The insect repellency potency combined with antibacterial and antifungal activities of wormwood position it as a potential candidate for prospective development into eco-friendly chemical pesticides. In this research, Wormwood essential oil was procured via ethanol water under ultrasonic scenarios and subsequently diluted with PEG 400 to formulate green chemical pesticides. The defensive efficacy of this green pesticide on plants was validated through 2 weeks of clustered plant growth experiments. Active constituents that exerted their effects were scrutinized by GC-MS. Furthermore, this green pesticide also displays efficacious effects on the prevention and management of aphids, exhibiting a dose-dependent relationship. 4-terpenol, eucalyptol, carvacrol, and L-borneol were identified by GC-MS as the predominant active constituents in this green chemical pesticide. Wormwood can be leveraged to develop green chemical pesticides, which can protect plants without contaminating the environment. [ABSTRACT FROM AUTHOR]

The identification and detection of pesticides is crucial to protecting both the environment and human health. However, it can be challenging to conveniently and rapidly differentiate between different types of pesticides. We developed a supramolecular fluorescent sensor array, in which calixarenes with broad-spectrum encapsulation capacity served as recognition receptors. The sensor array exhibits distinct fluorescence change patterns for seven tested pesticides, encompassing herbicides, insecticides, and fungicides. With a reaction time of just three minutes, the sensor array proves to be a rapid and efficient tool for the discrimination of pesticides. Furthermore, this supramolecular sensing approach can be easily extended to enable real-time and on-site visual detection of varying concentrations of imazalil using a smartphone with a color scanning application. This work not only provides a simple and effective method for pesticide identification and quantification, but also offers a versatile and advantageous platform for the recognition of other analytes in relevant fields. [ABSTRACT FROM AUTHOR]

Triazoles are compounds with various biological activities, including fungicidal action. They became popular through cholinesterase studies after the successful synthesis of the dual binding femtomolar triazole inhibitor of acetylcholinesterase (AChE, EC 3.1.1.7) by Sharpless et al. via in situ click chemistry. Here, we evaluate the anticholinesterase effect of the first isopropanol triazole fungicide mefentrifluconazole (Ravystar®), developed to overcome fungus resistance in plant disease management. Mefentrifluconazole is commercially available individually or in a binary fungicidal mixture, i.e., with pyraclostrobin (Ravycare®). Pyraclostrobin is a carbamate that contains a pyrazole ring. Carbamates are known inhibitors of cholinesterases and the carbamate rivastigmine is already in use for the treatment of Alzheimer's disease. We tested the type and potency of anticholinesterase activity of mefentrifluconazole and pyraclostrobin. Mefentrifluconazole reversibly inhibited human AChE and BChE with a seven-fold higher potency toward AChE (Ki = 101 ± 19 μM). Pyraclostrobin (50 μM) inhibited AChE and BChE progressively with rate constants of (t1/2 = 2.1 min; ki = 6.6 × 103 M−1 min−1) and (t1/2 = 1.5 min; ki = 9.2 × 103 M−1 min−1), respectively. A molecular docking study indicated key interactions between the tested fungicides and residues of the lipophilic active site of AChE and BChE. Additionally, the physicochemical properties of the tested fungicides were compared to values for CNS-active drugs to estimate the blood–brain barrier permeability. Our results can be applied in the design of new molecules with a lesser impact on humans and the environment. [ABSTRACT FROM AUTHOR]