Search

In order to discover better inhibitors of the complex III, 14 compounds were selected from the Specs database by the gradual filtering method and their antifungal activities in vitro were evaluated. The results showed that, at the concentration of 50 μg/mL, all of the 14 compounds exhibited the fungicidal activities against 5 phytopathogenic fungi, in cluding Sclerotinia sclerotiorum, Rhizoctonia solani, Phytophthora infestans, Fusarium oxysporum f. sp. vasinfectum and Botrytis cinerea. Among those 14 compounds, compound 9 against better activity than the commonly used fungicide azoxystrobin, and the EC50 value of the compound 9 against the aforementioned phytopathogenic fungi were 8.42, 74.89, 80.64, 96.17 and 32.94 μg/mL, respectively. To further investigate the molecular mechanism of compound 9, the molecular docking and molecular dynamics simulation were conducted. The result showed the compound 9 and azoxystrobin had similar binding conformation and both of them formed a hydrogen bond with Glu(C271) in the active site. This study on compound 9 provides more insight into the molecular mechanism of the complex III inhibition and sets the foundation for future researches. [ABSTRACT FROM AUTHOR]

An effective broad-spectrum fungicide, azoxystrobin (AZ), has been widely detected in aquatic ecosystems, potentially affecting the growth of aquatic microorganisms. In the present study, the eukaryotic alga Monoraphidium sp. and the cyanobacterium Pseudanabaena sp. were exposed to AZ for 7 days. Our results showed that 0.2–0.5 mg/L concentrations of AZ slightly inhibited the growth of Monoraphidium sp. but stimulated Pseudanabaena sp. growth. Meanwhile, AZ treatment effectively increased the secretion of total organic carbon (TOC) in the culture media of the two species, and this phenomenon was also found in a freshwater microcosm experiment (containing the natural microbial community). We attempted to assess the effect of AZ on the function of aquatic microbial communities through metabolomic analysis and further explore the potential risks of this compound. The metabonomic profiles of the microcosm indicated that the most varied metabolites after AZ treatment were related to the citrate cycle (TCA), fatty acid biosynthesis and purine metabolism. We thereby inferred that the microbial community increased extracellular secretions by adjusting metabolic pathways, which might be a stress response to reduce AZ toxicity. Our results provide an important theoretical basis for further study of fungicide stress responses in aquatic microcosm microbial communities, as well as a good start for further explorations of AZ detoxification mechanisms, which will be valuable for the evaluation of AZ environmental risk. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Abstract The applicant Syngenta submitted a request to the competent national authority in the United Kingdom to evaluate the confirmatory data that were identified for azoxystrobin in the framework of the MRL review under Article 12 of Regulation (EC) No 396/2005 as not available, and to consider new good agricultural practices (GAPs) for lettuces and other salad plants. To address the data gaps, new residue trials performed on open leaf varieties of lettuce supporting adjusted indoor, northern and southern GAPs, an assessment of the genotoxicity of the livestock metabolites L1, L4 and L9 and an assessment of the human dietary exposure to the livestock metabolites L1, L4 and L9 were submitted. The data gaps were considered partially addressed. The new information provided may require a revision (lowering) of the existing MRLs for lettuce and other salad plants and further risk management consideration for MRLs in animal commodities.

Application of pesticides during flowering of crops can result in exposure of pollinating insects such as honey bees, bumble bees and wild bees. In addition, residues of pesticides in bee products like honey may result from such applications. One of the overall goals of the German "FitBee" project was to determine the transport of plant protection products into the honey bee colony via individual bees and reduce the exposure to plant protection products by application technology approaches. One of these application technologies is DroplegUL, with which row crops can be sprayed underneath the canopy level, avoiding spray onto the blossoms. In the scope of the "FitBee" project (2011 to 2015), we conducted during five years semi-field experiments in Germany comparing conventional and DroplegUL spraying techniques regarding their implications to honeybee colony exposure. In this context, various trials were conducted in which residues in in-hive matrices (stored nectar, pollen) of bee colonies foraging on a model crop (oilseed rape) which was pesticide-treated with DroplegUL vs. conventional technology were measured.

Sclerotinia sclerotiorum (Lib.) de Bary is a plant pathogen with a wide host range, which causes significant yield and storage losses of edible roots and other plant products. Due to its ability to sclerotia formation, the efficient control of this pathogen is complicated. The study of five Bacillus strains (B. subtilis VKM B-3154D, VKM B-3155D, VKM B-3505D, VKM B-2998D, and B. amyloliquefaciens VKM B-3153D) showed their ability to produce polyene antibiotics suppressing the growth and development of plant pathogenic fungi. The maximum concentration of polyene compounds was revealed for B. subtilis VKM B-2998D. A high in vitro antifungal activity of a dry mycelium biomass (DMP) of Penicillium chrysogenum VKM F-4876D, B. subtilis VKM B-2998D, and their combination has been demonstrated in relation to S. sclerotiorum. A combined application of DMP (0.3 g/L) and azoxystrobin at low dosage (2.5 mg/L) showed a high suppressing activity towards S. sclerotiorum (100% growth inhibition) including inhibition of a sclerotia formation that may be useful for the development of efficient methods of crop protection against this plant pathogen. A high performance liquid chromatography (HPLC) analysis of DMP revealed the presence of mevastatin suggesting the mechanism of the DMP antifungal activity is based on the blocking of the ergosterol (the main component of fungal cell walls) biosynthesis. The results of the study provide a prerequisite to the development of biopreparations to control S. sclerotiorum, whose use may provide a reduction of concentrations of fungicides used in agriculture and the corresponding reduction of their negative xenobiotic impact on the environment and recovery of the ecological balance in the soil.

Fungicides often cause genotoxic stress and neurodevelopmental disorders such as autism (ASD). Fungicide-azoxystrobin (AZOX) showed acute and chronic toxicity to various organisms, and remained a concern for ill effects in developing neurons. We evaluated the neurotoxicity of AZOX in developing mouse brains, and observed prenatal exposure to AZOX reduced neuronal viability, neurite outgrowth, and cortical migration process in developing brains. The 50% inhibitory concentration (IC50) of AZOX for acute (24 h) and chronic (7 days) exposures were 30 and 10 μM, respectively. Loss in viability was due to the accumulation of reactive oxygen species (ROS), and inhibited neurite outgrowth was due to the deactivation of mTORC1 kinase activity. Pretreatment with ROS scavenger- N-acetylcysteine (NAC) reserved the viability loss and forced activation of mTORC1 kinase revived the neurite outgrowth in AZOX treated neurons. Intra-amniotic injection of AZOX coupled with in utero electroporation of GFP-labelled plasmid in E15.5 mouse was performed and 20 mg/kg AZOX inhibited radial neuronal migration. Moreover, the accumulation of mitochondria was significantly reduced in AZOX treated primary neurons, indicative of mitochondrial deactivation and induction of apoptosis, which was quantified by Bcl2/Bax ratio and caspase 3 cleavage assay. This study elucidated the neurotoxicity of AZOX and explained the possible cure from it.

Background: Fungicides impact on agriculture is reflected by the wide spread use of azoxustrobin (AZX) and metalxyl M, the active ingredients of premium fungicide used on more than 80 different crops. Objective: The present study aimed to investigate the hepato-renal-toxicity of premium fungicide on adult albino rats and focused on benefits of sesame oil in detoxification of toxicological effects of fungicides. Materials and methods: Thirty male albino rats allocated into five groups, -ve, +ve control and sesame oil groups. While the two other groups were treated with sesame oil before and after fungicide exposure daily by gavage for (28 days). Results: Exposure of male albino rats to Azoxystrobin fungicide resulted in liver and kidney injury as evidenced by increased liver and renal function bioindicator (ALT, AST, ALP, urea and creatinine)..Also, glutathione (GSH) was significantly decreases and malondialdhyde (MDA) was increased as oxidative stress biomarkers. In addition, degeneration of some tubular epithelial cells and hemorrhage in kidney and severe inflammatory cell infiltration in liver. Conclusion: The present study concluded that premium had induced functional and histological changes in liver and kidney male rats. Sesame oil successfully ameliorated the oxidative stress, hepatotoxicity and nephrotoxicity of fungicide. [ABSTRACT FROM AUTHOR]

In wheat, the increase in nitrogen use efficiency (NUE) and optimization of the nitrogen doses to be used are both very important aspects for improving sustainable and productive agriculture. The aim of this study was to investigate, under rainfed Mediterranean conditions, the influence of strobilurin treatment and N fertilization on durum wheat N use efficiency for yield (NUEy) and protein (NUEp) and on the contribution of their components, nitrogen uptake efficiency (UPE) and nitrogen utilization efficiency (NUtE). Two durum wheat cultivars (Saragolla and Sfinge) were grown for two years in field conditions under five nitrogen treatments (60 kg ha−1 N60; 90 and 120 kg ha−1 given two and three times; N90, N90T3, N120 and N120T3) comparing a control without strobilurin treatment (ST0) and one application of strobilurin (STaz). In Sfinge, STaz caused a decrease in UPE and NUEp and an increase in NUtE and NUEy. In Saragolla, the opposite behavior was observed. Moreover, strobilurin positively affected the contribution of UPE and negatively that of NUtE to NUEy only in Saragolla. Furthermore, strobilurin determined higher NUEy and NUEp values under most of the N treatments adopted in the drier year. With this study, we supported the hypothesis that in Mediterranean conditions, the possibility of reducing N rate application from 120 to 90 kg ha−1 with a strobilurin-based treatment, even in the absence of fungal diseases, could represent a useful agronomic strategy for durum wheat grown under drought conditions as those predicted under the ongoing climate change. [ABSTRACT FROM AUTHOR]

Biological control agents applied post-harvest may provide an effective way to manage leak of potatoes by competing with Pythium ultimum. The objective of this paper was to test the efficacy of various biological control agents and conventional post-harvest fungicides to manage leak. Two studies were performed with a Pseudomonas fluorescens triculture including desiccation tolerant variants of strains S11P12, P22Y05, and S22T04 in three formulations (a "fresh" triculture, dried on Kenite 700, or dried on Attapulgite clay) applied at a rate of 3.5 mL kg−1. A third study contained treatments of the P. fluorescens "fresh" triculture, triculture dried on Kenite, triculture dried on Kenite blended with a fungicide containing a three-way mixture of azoxystrobin, fludioxonil, and difenoconazole (Azo+Flu+Dfz, 0.033 mL kg−1), and triculture dried on Kenite rehydrated with nutrient broth Medium 1 blended with the same fungicide. Other treatments included Pseudomonas syringae (3.5 mL kg−1) in Studies 1 and 2, while hydrogen peroxide and peroxyacetic acid (0.042 mL kg−1), phosphorous acid (4.2 mL kg−1), and Azo+Flu+Dfz (0.033 mL kg−1) were used in all three studies. The three studies were each repeated twice using unwashed tubers (cv. 'Russet Burbank') that were wounded and inoculated with P. ultimum. After inoculation, tubers were treated, then stored at 21 C for four days prior to disease evaluation. In Study 1, none of the formulations of P. fluorescens triculture significantly controlled leak compared to the inoculated control; however, the "fresh" triculture formulation significantly decreased leak incidence by 24% in Study 2. In all three studies the three-way fungicide mixture Azo+Flu+Dfz resulted in lower leak incidence (1, 7, and 24%, in studies 1, 2, and 3 respectively) compared with the inoculated control (12, 37, and 50% leak incidence, in studies 1, 2, and 3 respectively). Study 3 showed the formulations of P. fluorescens strains were not effective in leak control but when combined with Azo+Flu+Dfz leak incidence significantly decreased compared to the inoculated control. The lowest leak incidence was seen when the triculture component of the fungicide mix was rehydrated with Medium 1 in Study 3. The P. fluorescens triculture formulations mixed with Azo+Flu+Dfz and rehydrated with Medium 1 had slightly higher bacterial counts than the "fresh" triculture and the triculture dried on Kenite, potentially indicating a greater activity level afforded by cell revival in dilute culture medium. P. syringae, phosphorous acid and hydrogen peroxide-peroxyacetic acid were ineffective in controlling leak in all three studies. The efficacy of the Azo+Flu+Dfz mixture appears promising for the management of leak in storage. The efficacy of P. fluorescens tricultures used alone was inconsistent in limiting leak incidence (only significant in 1 of 3 studies), and additional research and development may be warranted to realize its potential as biological control agent. [ABSTRACT FROM AUTHOR]

Saprolegniasis often cause a significant economic losses to fish hatchery and intensive fish industry. The treatment of saprolegnoid diseases with malachite green seems to have harmful effect and is considered as a mutagenic and carcinogenic substance. The teratogenic and carcinogenic potential of malachite green increased the necessity to find an effective alternative treatment to control the disease. In the present study, seven fungicides used in agriculture were investigated to control Saprolegnia parasitica and S. diclina in vitro. The antifungal activity of each fungicide was compared with that of malachite green as reference fungicide using food poisoning technique. Fish toxicity of the effective fungicides was performed to detect the most applicable fungicides in fish aquarium. Four of seven fungicides were found to be effective against the two saprolegnoid fungi. Azoxystrobin and metalaxyl were the most effective fungicides inhibited fungal growth of the two saprolegnoid fungi completely at concentration of 200 ppm and 250 ppm respectively while cyazofamid and etridiazole were moderately effective. Acute toxicity assay of the two effective fungicides showed metalaxyl was low toxic to fish with LC 50 of 360 ppm while azoxystrobin was 225 ppm. Hence, it was confirmed that 200 and 250 ppm of azoxystrobin and metalaxyl which completely inhibited mycelial growth of the saprolegniod fungi could be safely used for saprolegniasis control. These fungicides which proved to be effective and fishery safer may be applicable as a aquatic fungicides avoiding teratogenic and carcinogenic risk of malachite green. [ABSTRACT FROM AUTHOR]

Chilli (Capsicum annum) is the fourth most important vegetable crop in the world and first in Asia, Anthracnose (fruit rot and die back) caused by Colletotrichum capsici (Syd. Butler and Bisby) is prevalent throughout the chilli growing areas of India. Field experiments were carried out to study the effect of Azoxystrobin 120 + Tebuconazole 240 SC at the rate of 830, 676, and 520ml/ha along with other market fungicides on anthracnose disease of chilli caused by Colletotrichum capsici. Maximum control of C. capsici (15.93, 15.41 and 14.72 after first, second and third spray leaves and fruit respectively) was recorded with 249 g a.i. The fruit yield also has significantly increased recorded the maximum green chilli yield with 9.13 t/ha per cent yield increase over control. No phytotoxic effects such as leaf tip/surface injury, wilting, vein clearing necrosis, epinasty, hyponasty, fruit injury of azoxystrobin 25 SC were observed at the doses of 3320, 1660, and 830 ml/ha. The occurrence of natural enemies spiders, Dragon fly, Damsel fly and wasps population were not affected in the plots treated with Azoxystrobin 120 + Tebuconazole 240 SC @ 830 ml/ha. [ABSTRACT FROM AUTHOR]

Chilli (Capsicum annuum L.) is an important cash crop among the spices. powdery mildew is caused by Leveillula taurica (Lev.) Arn., is a major constraint in chilli production in India, causing heavy yield loss ranging from 14 to 20%. The present study was taken up with an aim to evaluate the Studies of Bioefficacy and phytotoxicity of Azoxystrobin 120 + Tebuconazole 240 SC against Powdery mildew (Leveillula taurica) in Chilli, Experimental findings indicate that efficacy of the fungicidal products of Azoxystrobin 120 + Tebuconazole 240 SC (249 gm/ha, 830ml/ha)to increase crop yield, and disease management of powdery mildew was observed more or less equal to Azoxystrobin 23 % EC, Tebuconazole 25.9 % EC, Myclobutanil 10 % WP and Difenoconazole 25 % EC (Market sample) Among the different doses of Azoxystrobin 120 + Tebuconazole 240 SC plants treated @ 830 ml/ha was recorded highest yield and lowest powdery mildew disease incidence followed by dose 676 ml/ha and 520 ml/ha. When compared to control. The occurrence of natural enemies spiders, Dragon fly, Damsel fly and wasps population were not affected in the plots treated with Azoxystrobin 120 + Tebuconazole 240 SC @ 830 ml/ha Phytotoxicity. The use of Azoxystrobin 120 + Tebuconazole 240 SC fungicide is found to be safe to chilli crop and none of the symptoms like chlorosis, necrosis, scorching, epinasty and hyponasty symptoms were recorded even at the highest dosage of treatment viz., 3320 ml/ha and up to 10 days of after I, II and III spraying. [ABSTRACT FROM AUTHOR]

Extensive disease oriented field surveys were conducted to record incidence and severity of banded leaf and sheath blight of maize in different maize growing districts of Punjab during Kharif seasons of 2015 and 2016. Mean disease occurrence of banded leaf and sheath blight was highest in Hoshiarpur (72.5%) followed by Rupnagar (70.1%) district during both the years. The highest mean disease incidence (11.3%) and severity (7.8%) were also recorded in Hoshiarpur district. Out of eight fungicides screened against Rhizoctonia solani, azoxystrobin 250 g/I +difenoconazole 125 g/I (Amistar Top 325 SC) and trifloxystrobin 25%+tebuconazole 50% (Nativo 75 WG) proved highly effective giving 87.4 and 84.7 per cent inhibition in colony growth respectively at 100 ppm and completely inhibited colony growth at 200 ppm. ED50 value calculated for these fungicides was less than 1 pg/ml. Minimum mean disease severity of 10.40 and 11.14 percent was recorded with 0.05% foliar spray of azoxystrobin 250 g/I +difenoconazole 125 g/I (Amistar Top 325 SC) (10.40%) and trifloxystrobin 25%+tebuconazole 50% (Nativo 75 WG) respectively. Azoxystrobin 250 g/I +difenoconazole 125 g/I (Amistar Top 325 SC) gave maximum mean grain yield of 31.3 q/acre with 80.73 per cent increase in yield over untreated control under field conditions. [ABSTRACT FROM AUTHOR]

French bean rust incited by Uromyces appendiculatus is particularly prominent in pencil type beans in mid hills of Himachal Pradesh. Effect of different systemic, non-systemic and combi fungicides were studied for the management of bean rust. Under in vitro conditions azoxystrobin, difenoconazole + azoxystrobin, pyraclostrobin + metiram, kresoxim - methyl, fluopyram + tebuconazole, trifloxystrobin + tebuconazole, propiconazole + difenoconazole resulted in cent per cent inhibition of urediniospore germination at 200 ppm concentration. Difenoconazole + azoxystrobin provided up to 96 h post-infection activity while non-systemic fungicides i.e. mancozeb and chalorothalonil were found least effective with <24 h post -infection activity under glasshouse conditions. For the management under field conditions four foliar sprays of azoxystrobin (0.1%) at 10 days interval was found most effective in reducing bean rust severity to 3.81% and increased green pod yield by >100%. For effective management of this devastating disease activities of various fungicides (strobilurins and EBI's) having different modes of action can be utilized in formulating a spray schedule. [ABSTRACT FROM AUTHOR]

Sugar beet is a major crop in Morocco and Cercospora leaf spot is one of its most important fungal diseases. In Morocco, thiophanate methyl (benzimidazole) and difenoconazole (demethylation inhibitor, DMI) have been used extensively in the management of Cercospora leaf spot. In this study, samples of Cercospora beticola Sacc were collected from four major production areas. The identification of all isolates was confirmed using a PCR test with specific primers. Radial mycelia growth of each isolate in unmodified potato dextrose agar medium was compared to mycelia growth in the same medium modified with thiophanate methyl (1, 5, 10 and 50 ppm) or the DMIs difenoconazole, epoxiconazole and tetraconazole (0.1, 0.5, 1, 5, 10 and 50 ppm) or the quinone outside inhibitors (QOIs) azoxystrobin and trifloxystrobin (1, 5, 10 and 50 ppm). The percentage of inhibition obtained was used for the half maximal effective concentration (EC50) calculation. All the isolates showed resistance to the thiophanate methyl molecule to different degrees. Three groups were identified: low resistance with EC50 less than 100 ppm, moderate resistance with EC50 between 100 and 1000 ppm, and very resistant with EC50 more than 1000 ppm. For difenoconazole, 41% of isolates were sensitive (EC50 < 0.05 ppm) and 59% were resistant, while for tetraconazole and epoxiconazole 6% were sensitive (EC50 < 0.01 ppm), 66.7 % had medium resistance (0.01 < EC50 < 1 ppm) and 27.3% were resistant (EC50 > 1 ppm). For QOIs, azoxystrobin was less effective for mycelial inhibition than trifloxystrobin, with 54.5% of isolates with resistance to azoxystrobin (EC50 > 100 ppm). [ABSTRACT FROM AUTHOR]

The applicant Syngenta submitted a request to the competent national authority in the United Kingdom to evaluate the confirmatory data that were identified for azoxystrobin in the framework of the MRL review under Article 12 of Regulation (EC) No 396/2005 as not available, and to consider new good agricultural practices (GAPs) for lettuces and other salad plants. To address the data gaps, new residue trials performed on open leaf varieties of lettuce supporting adjusted indoor, northern and southern GAPs, an assessment of the genotoxicity of the livestock metabolites L1, L4 and L9 and an assessment of the human dietary exposure to the livestock metabolites L1, L4 and L9 were submitted. The data gaps were considered partially addressed. The new information provided may require a revision (lowering) of the existing MRLs for lettuce and other salad plants and further risk management consideration for MRLs in animal commodities. [ABSTRACT FROM AUTHOR]

This study examined the effect of three synthetic fungicide, maneb "Manebe80®" chlorothalonil "Bravo®" and azoxystrobin "Ortiva®" on the incidence of ascochyta blight (AB) of chickpea caused by Ascochyta rabiei using three chickpea germplasm (ILC482, ILC484 and Flip 1025). The results, statisticaly reliable (C.V.< 20%), indicated the in vitro test of chemical control has significant effect at P0.01, on the mycelial growth of pathogen. All three fungicides caused important MGI% (Mycelial growth inhibition rate), which varied between 30 and 66%. There was a significant action induced by chlorothalonil fungicide (54 – 65%), followed closely by azoxystrobin (46 – 63%) and maneb (30 – 65%). In the in vivo test of chemical control for AB incidence by detached leaves showed a remarkable percentage of reduction in the severity of ascochyta blight varied between 20 and 80%. We noticed that the systemic fungicide like azoxystrobin can reduce the ascochyta blight severity (RDS%), with ranging between 71 and 80%, for other two contact fungicides (chlorothalonil and maneb), the mycelia growth inhibition rate was close to 50% (from 20 to 47%). These results indicated that the systemic fungicides, like azoxystrobin, have a significantly reduced the incidence and development of ascochyta blight disease in the susceptible cultivars (ILC1929, ILC263 and ILC484). [ABSTRACT FROM AUTHOR]

A method was developed for the simultaneous qualitative and quantitative determination of azoxystrobin and its relevant impurity (Z)-azoxystrobin using high performance liquid chromatography with diode array detector (HPLC-DAD) in suspension concentrate (SC) pesticide formulations, with the aim of the product quality control. Method validation was realized according to SANCO/3030/99 rev. 5. The proposed method was characterized by acceptable accuracy and precision. The repeatability expressed as ratio standard deviation (%RSD) to relative standard deviation (%RSDr) was lower than 1, whereas individual recoveries were in the range of 97–103% and 90–110% for azoxystrobin and (Z)-azoxystrobin, respectively. The limit of quantification (LOQ) for the impurity ((Z)-azoxystrobin) amounted to 0.3 µg mL−1 and was acceptable because it was lower than the maximum permitted level according to Commission Implementing Regulation (EU) No 703/2011 of 20 July 2011 for the active substance (azoxystrobin) being 25 g kg−1 of the azoxystrobin content found. The method described in this paper is simple, precise, accurate and selective as well as represents a new and reliable way of simultaneous determination of azoxystrobin and its relevant impurity in formulated products. [ABSTRACT FROM AUTHOR]

In Hungary, sunflower is the third most important arable crop, which has a lot of pathogenic fungi. One of these fungi is the Macrophomina phaseolina, which is a well-known fungus in all over the world, since this pathogen has more than 700 host plants. In Hungary, several host plants can be found as well. The M. phaseolina produces microsclerotia, which can survive in the soil and residues for almost 10 years. For now, there is no efficient treatment against this pathogen because of this fungus, since it is extremely resistant and cannot be destroyed easily. The only effective treatment against the fungus is genetic defence. In this study, three different fungicides were tested in vitro against the fungus. The Mirage (prochloraz) seemed to be the most effective fungicide as it completely arrested the hyphal growth. In contrast, the Amistar Xtra (azoxystrobin and ciprochonazol) has only a minor effect on the growth of M. phaseolina. Thirdly, the Retengo (pyrachlostrobin) arrested the hyhpal growth of the fungus with 71% at 100 ppm, in other words, the use of this fungicide seems promising. [ABSTRACT FROM AUTHOR]

Based on the reported isomorphism of azoxystrobin (AZO) solvates, five novel AZO solvates, including the dimethyl succinate solvate (AZO–DMS), ethyl butyrate solvate (AZO–EB), thiophene solvate (AZO–TP), furan solvate (AZO–FN), and 1,2-diethoxyethane solvate (AZO–DEE), were successfully designed and prepared experimentally. The single crystal structures of AZO–DMS and AZO–FN solvates were determined by single crystal X-ray diffraction. The properties of the five solvates were comprehensively characterized by powder X-ray diffraction and thermal analysis. The Hirshfeld surface analysis and intermolecular interactions of the AZO conformation in the crystal structures were investigated. This study demonstrates that the solvent molecular size is important for the formation of isomorphic AZO solvates. [ABSTRACT FROM AUTHOR]

Late wilt is a destructive disease of corn: outbreaks occur at the advanced growth stage and lead to severe dehydration of susceptible hybrids. The disease’s causal agent is the fungus Magnaporthiopsis maydis, whose spread relies on infested soils, seeds, and several alternative hosts. The current study aimed at advancing our understanding of the nature of this plant disease and revealing new ways to monitor and control it. Two field experiments were conducted in a heavily infested area in northern Israel seeded with highly sensitive corn hybrid. The first experiment aimed at inspecting the Azoxystrobin (AS) fungicide applied by spraying during and after the land tillage. Unexpectedly, the disease symptoms in this field were minor and yields were high. Nevertheless, up to 100% presence of the pathogen within the plant’s tissues was measured using the quantitative real-time PCR method. The highest AS concentration tested was the most effective treatment, and resulted in a 6% increase in cob yield and a 4% increase in A-class yield. In the second experiment conducted in the following summer of the same year in a nearby field, the disease outbreak was dramatically higher, with about 350 times higher levels of the pathogen DNA in the untreated plots’ plants. In this field, fungicide mixtures were applied using a dripline assigned for two coupling rows. The most successful treatment was AS and the Difenoconazole mixture, in which the number of infected plants decreased by 79%, and a 116% increase in crop yield was observed, along with a 41% increase in crop quality. Evaluation of the effectiveness of the treatments on the plants’ health using a remote, thermal infra-red sensitive camera supported the results and proved to be an essential research tool. [ABSTRACT FROM AUTHOR]

Azoxystrobin (AZ), pyraclostrobin (PYR) and coumoxystrobin (COU) exert negative impacts on Chlorella vulgaris. Thus, in this study, C. vulgaris was used to assess the respiratory toxicity of AZ, PYR and COU by determining the acute toxicity, complex III activity and ATP viability. The 96 h-EC50 values of AZ, PYR and COU for C. vulgaris were 1.85, 2.21 and 1.62 mg/L, respectively. AZ, PYR and COU exerted significant effects on complex III activity and ATP viability after exposure to 0.71, 1.01 and 1.08 mg/L of the fungicides. The binding potentials of AZ, PYR and COU toward ubiquinone were − 10.44, − 9.31 and − 12.98 kcal/mol, respectively, which had adverse effects on amino acids. These results provided new insight into the potential acute respiratory toxicity mechanisms of these strobilurin fungicides in algae. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the synergistic effect of five adjuvants on azoxystrobin was investigated. The surface tension, the critical micelle concentration (cmc) and the maximum retention (Rm) were determined. The control efficacy of azoxystrobin and adjvants were compared by pot experiment. The results showed that the five adjuvants could efficiently reduce the surface tension, and increase Rm value on plant leaves. Rm value of Silwet408 was 7.32 mg/cm2 on corn leaves. Rm value of Beidatong was 11.16 mg/cm2 on wheat leaves. The five adjuvants could dramatically increase the control efficacy of azoxystrobin against wheat powdery mildew, soybean rust and corn rust. In terms of corn rust, the synergistic effect of Maidao (EC50 value 0.016 mg/L) was the best one, followed by Beidatong (EC50 value 0.029 mg/L). With regard to wheat powdery mildew, the synergistic effect of NF-100 (EC50 0.009 mg/L) and Silwet408 (EC50 0.009 mg/L) were both good. As for soybean rust, the synergistic effect of Maidao (EC50 value 0.006 mg/L) and Silwet408 (EC50 value 0.007 mg/L) were good. All in all, Silwet408 and Maidao have good synergistic effect with azoxystrobinto three plant diseases. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The use of nanotechnology to enhance pesticide formulations holds the promise of reduced pesticide use, reduced mobility in soils, and overall improvements in agricultural practices while simultaneously maintaining yields. However, the toxicity of nano-enabled pesticides, including azoxystrobin (Az), has not been well studied compared with their conventional form. This study investigates both lethal and sub-lethal endpoints in zebrafish embryos up to 120 h post-fertilization (hpf) under either laboratory light or simulated UV light. The median lethal concentration (LC50) value of nano-enabled Az (nAz) was significantly lower than the conventional form (Az). Interestingly, artificial UV light significantly increased toxicity (decreased LC50) of both Az and nAz. Malformations were not observed but the remaining yolk sac volume was significantly increased in both types of Az at both light conditions. This decreased yolk consumption is in agreement with reduced oxygen consumption and heart rate. Catalase enzyme activity was only reduced to UV light while superoxide dismutase activity was significantly reduced by co-exposure of UV light, and either type of Az at a nominal concentration of 100 μg L−1. The co-exposure of Az at 100 μg L−1 and UV light significantly upregulated sod1, sod2, and gpx1b expression and both types of Az significantly reduced gpx1a expression. Lipid peroxidation was significantly increased in nAz and Az at 100 μg L−1 under laboratory light, while UV light induced even higher level of lipid peroxidation. The results will provide important information on the toxicity of nAz under ecologically realistic conditions. [ABSTRACT FROM AUTHOR]

Using LC–MS/MS, a rapid and sensitive method for the simultaneous determination of pyraclostrobin and azoxystrobin residues in banana matrices (leaf and whole banana) and soil was established. The samples were extracted using acetonitrile and purified through C18 dispersive solid‐phase extraction. The average recovery of the analytes in various matrices was in the range of 77.3%–103.9% with an RSD range of 0.9%–9.5%. The initial deposition amounts of pyraclostrobin and azoxystrobin at 2 h in the banana leaves of the mineral oil group were 1.43 and 1.31 times in Guangxi, and 2.10 and 1.81 times in Hainan for the water group, whereas those in the soil of the water group were 3.45 and 3.03 times in Guangxi, and 2.14 and 3.48 times in Hainan for the mineral oil group. The half‐lives in the leaves and soil of the mineral oil group were not remarkably different from those of the water group. The terminal residue of the analytes on the whole banana was <0.02 mg/kg at 14 days after application from the two sites. The results of this work may indicate and promote the safety of using pyraclostrobin and azoxystrobin in banana production, especially with mineral oil spray adjuvants. [ABSTRACT FROM AUTHOR]

BACKGROUND: Several diseases and insects may cause damage to the normal growth of cucumber. Azoxystrobin and meptyldinocap, because of their novel mode of action, are effective against pathogens that have developed reduced sensitivity to other fungicides. Azoxystrobin is persistent in various crops and environments. However, there is a lack of research on the dissipation of these two pesticides, especially meptyldinocap. RESULTS: Analytes could be quantified with decent recoveries of 90–101%, with relative standard deviations (RSDs) of 3.0–10.1%. The terminal residues of meptyldinocap and azoxystrobin in cucumber were all < limit of quantification (LOQ) (0.02 and 0.05 mg kg−1). The half‐lives of meptyldinocap and azoxystrobin were 0.8–1.1 and 1.2–2.8 days, respectively. The processing factors (PFs) for washing were all < 1, but the removal rate for washing was < 29.0%. Peeling had a significant effect on the removal of pesticide. The largest residue reductions were noticed through the pickling process, but special care should be taken regarding residues in the pickling solution as pesticides could transfer to them from cucumber. A more interesting finding was that the degradation of two pesticides was accelerated by the addition of calcium oxide. CONCLUSION: Pesticide residues on cucumber decreased after these processes. These results enable the health‐risks from dietary exposures to pesticide residues to be characterized. They enable maximum residue limits (MRLs) to be established for pesticide residues in food products. They also assist the optimization of food processing with regard to pesticide residue dissipation. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Rapeseed isolates of Sclerotinia sclerotiorum (Lib.) de Bary 1884 from the Nitra Region of Slovakia were investigated for their in vitro sensitivity to azoxystrobin and picoxystrobin; and for determining their EC50 value. The growth of S. sclerotiorum was evaluated on a PDA medium amended with the selected fungicide´s active ingredient at 4 different concentrations – 0.08, 0.83, 8.33, and 83.30 ppm. The overall mean EC50 values for azoxystrobin and picoxystrobin were 2.73 ppm and 3.12 ppm, respectively. The majority of the isolates had resistance factors up to 20, which suggests a shift in the S. sclerotiorum population sensitivity towards the resistance. [ABSTRACT FROM AUTHOR]

Stem-end rot caused by Lasiodiplodia theobromae is one of the most devastating diseases of papaya in northeastern Brazil. It is most effectively controlled by applications of fungicides, including site-specific fungicides at risk for resistance development. This study investigated the molecular mechanisms of reduced sensitivity to the QoI fungicide azoxystrobin and resistance to the MBC fungicide thiophanate-methyl in L. theobromae from Brazilian orchards. The EC 50 values for azoxystrobin in sixty-four isolates ranged from 0.36 μg/ml to 364.24 μg/ml and the frequency distribution of EC 50 values formed a multimodal curve, indicating reduced sensitivity to azoxystrobin. In detached fruit assays reduced sensitive isolates were not controlled as effectively as sensitive isolates at lowest label rate. Partial fragments were obtained from target genes β- tubulin (751 bp) and Cytb (687 bp) of isolates resistant to thiophanate-methyl and reduced sensitivity to azoxystrobin. Sequence analysis of the β- tubulin fragment revealed a mutation corresponding to E 198 K in all thiophanate-methyl-resistant isolates, while reduced sensitivity to axoxystrobin was not attributable to Cytb gene alterations. The target gene-based mechanism conferring resistance to thiophanate-methyl will likely be stable even if selection pressure subsides. However, the mechanism conferring reduced sensitivity to azoxystrobin is not based on target gene modifications and thus may not be as stable as other genotypes with mutations in Cytb gene. Unlabelled Image • Reduced sensitivity to azoxystrobin in Lasiodiplodia theobromae from papaya was observed. • Reduced sensitivity to azoxystrobin was not attributable to Cytb gene alterations. • Resistance to thiophanate-methyl was associated with E 198 K mutation in β-tubulin gene. • No-cross-resistance was found between azoxystrobin and thiophanate-methyl. [ABSTRACT FROM AUTHOR]

In this study, three potato cultivars with different drought resistance were used as the testing materials in potted-experiments. Azoxystrobin was used as the ditch treatment chemicals (A) before planting. The group with full irrigation was the control (CK, soil volume water content θw: 60%-70%). The drought group was the one with water stress treatment (D, θw: 30%-40%). The group (A-D) was treated by both drought and azoxystrobin. The physiological basis of the potato drought tolerance improvement induced by azoxystrobin was investigated by measuring leaf photosynthetic parameters, antioxidant enzyme activities, malondialdehyde (MDA) and proline content, potato yield per plant and tuber quality. The results showed that azoxystrobin could effectively enhance the photosynthetic rate and stomatal conductance of potato leaves. Under full irrigation conditions, application of azoxystrobin could increase the activities of CAT and APX, which played a role in the delay of the senescence of plants. Under drought stress conditions, the accumulation of MDA and proline content in leaves was reduced, resulting in an increase in drought tolerance of plants. Azoxystrobin respectively increased the yields of Qingshu No.9, Longshu No.6 and Atlantic by 30.74%, 59.87% and 5.90%, compared to those of the CK. And A-D treatment respectively increased the yields of Qingshu No.9, Longshu No.6 and Atlantic by 15.17%, 43.43% and 16.49%, compared to those of the D group. In addition, the comprehensive quality scores of A Qingshu No.9, Longshu No.6 and Atlantic respectively were 1.184, 2.856, 0.621, and A-D respectively were −1.112, −0.240, −0.349. It can be seen that azoxystrobin was beneficial to the improvement of potato tubers quality under drought stress. [ABSTRACT FROM AUTHOR]

Asian soybean rust is one of the most destructive diseases that can be found in this crop. It can be largely controlled by fungicide application. The objective was to assess the sensitivity of P. pachyrhizi isolates to fungicides. The tests were performed in a completely randomized design, with six replicates. The sensitivity of twelve isolates to site-specific and multisite fungicides at concentrations of 0.1; 1.0; 10.0, and 100.0 mg L-1, plus a control with absence of fungicide (0.0 mg L-1) was assessed. Soybean leaflets were immersed in the appropriate fungicide solutions, disposed in wet chambers in plastic boxes, and inoculated using each uredinia suspension of P. pachyhrizi (5.0 x 104 uredospores mL-1), separately. Boxes were incubated for 20 days at a temperature of 23°C and a 12-hour photoperiod. Next, the number of uredinia per cm² on the abaxial face of each leaflet was evaluated. The active ingredients prothioconazole, trifloxystrobin, fluxapiroxade, trifloxystrobin + prothioconazole, trifloxystrobin + bixafen + prothioconazole, azoxystrobin + benzovindiflupyr and azoxystrobin + benzovindiflupyr + diphenoconazole were highly fungitoxic for the majority of the isolates, with EC50 lower than 1.0 mg L-1. Diphenoconazole, azoxystrobin, andfenpropimorph were considered moderately fungitoxic for nine of the twelve isolates, with EC50 between 1 and 10 mg L-1. The multisites mancozeb and copper oxychloride presented EC50 responses classified as low toxic for the twelve isolates and eight for chlorothalonil (EC50 between 10 mg L-1 and 50 mg L-1). Site-specific fungicides showed high-to-moderate fungitoxicity to P pachyrhizi isolates, even as the multisites presented moderate-to-less toxic activity. [ABSTRACT FROM AUTHOR]

The objective of this work was to find practical procedures to overcome methodological drawbacks encountered during studies on sunflower downy mildew. Techniques for recovering living isolates of Plasmopara halstedii from the field and for the preservation of infected leaf samples for further molecular analysis were developed. A Polymerase Chain Reaction (PCR)-based test for the detection of P. halstedii in sunflower leaves and a method to remove azoxystrobin from fungicide-treated seeds are proposed. In situ-inoculations of pre-germinated seeds allowed the recovery of living isolates from the field. Three sample-preservation methods were evaluated (silica, heating and lyophilization) resulting in high yield and quality of the DNA extract. It was detected the presence of the pathogen in symptomless leaves through PCR using molecular markers based on expressed sequence tags. A treatment using sodium hypochlorite is recommended for the removal of azoxystrobin from fungicide treated seeds. [ABSTRACT FROM AUTHOR]

Aim: To reduce the contamination arising from abuse of commercial pesticide formulations, the coaxial electrospray (CES) method was used for one-step microencapsulation and spraying of pesticides. Methods: After optimisation of process parameters, polymeric microcapsules with different structures were fabricated as the carriers of azoxystrobin (AZS). For the resultant microcapsules, the sustained pesticide release was verified in vitro and the adhesion properties were investigated through a normalised rinsing test. Results: The maximum encapsulation efficiency of the fabricated AZS-loaded microcapsules was 99.14%. Compared to commercial AZS aqueous suspension, the microcapsules fabricated by the CES method exhibited improved sustained release performance of AZS, which could be readily controlled by adjusting the shell thicknesses. Moreover, highly enhanced adhesion performance was observed for the AZS-loaded microcapsules directly sprayed in CES process. Conclusions: The CES process is promising to be applied as a one-step microencapsulation and spraying technology for improving pesticide utilisation and reducing environmental pollution. [ABSTRACT FROM AUTHOR]

Extensive use of the fungicides azoxystrobin (AZ) and pyraclostrobin (PYR) can have negative effects on aquatic environments, but comprehensive studies on their effect on aquatic microbial communities are still lacking. We found that AZ and PYR could both inhibit the growth of Chlorella vulgaris, but PYR also inhibited Microcystis aeruginosa more strongly than did AZ. High-throughput sequencing analysis showed that AZ promoted the growth of Cyanobacteria in microcosms, and both PYR and AZ disturbed the ecological balance in the aquatic bacterial community and created distinct ecological risks. Our study suggests that the ecological risk of fungicides is complex, and fungicide use should be better managed to reduce potential risks to the environment. [ABSTRACT FROM AUTHOR]

Tebuconazole (TBZ) and azoxystrobin (AZX) are fungicides frequently used in rice cultivation. Despite protecting crops against fungal diseases, these compounds can contaminate the natural environments close to the crops, exerting negative effects on non-target organisms, the present study aimed to characterize the contamination by fungicides of a river that flows in an area dominated by rice cultivation in the north of the state of Santa Catarina, SC, Brazil. Concentrations of TBZ and AZX found in the field were used to evaluate their negative effects on development, biochemical biomarkers and histopatology of the liver of a native tadpole species, the hammerfrog (Boana faber). Tadpoles were exposed for 16 days to the lowest (1.20 μg/L) and highest (2.60 μg/L) concentration of TBZ, lowest (0.70 μg/L) and highest (1.60 μg/L) concentration of AZX, and the mix of both fungicides at lowest and highest concentration of each found in field analyses. Exposure to the lower TBZ concentration and both concentrations of the Mix accelerated the development of tadpoles. AZX caused an increase in the activities of glutathione S-transferase (GST), carboxylesterase (CbE) and glucose-6-phosphate dehydrogenase (G6PDH) in the liver, an increase in the levels of protein carbonyls (PC) in the liver and an increase in the activity of acetylcholinesterase (AChE) in muscle of tadpoles. TBZ, on the other hand, generated an increase in GST, G6PDH, PC and histopathological severity scores in liver and in muscle AChE activity. The effects were more intense in the groups exposed to the Mix of contaminants. No treatment altered brain AChE. The data showed that the fungicides from in rice cultivation found in natural aquatic environments around the crops pose risks to the health of the animals, compromising their metabolism and development. [Display omitted] • Azoxystrobin (AZX) and tebuconazole (TBZ) were found in aquatic environments close to rice crops. • Effects of exposure to AZX and TBZ in Boana faber tadpoles were evaluated. • AZX exposure resulted in oxidative stress. • TBZ exposure accelerated tadpole development, caused oxidative stress and hepatic lesions. • Exposure to mixtures of AZX and TBZ caused more pronounced effects in tadpoles. [ABSTRACT FROM AUTHOR]

A widely applied pesticide of azoxystrobin, is increasingly detected in the water environment. Concern has been raised against its potential detriment to aquatic ecosystems. It has been shown that exposure to azoxystrobin interfere with the locomotor behavior of zebrafish larvae. This study aims to investigate whether exposure to environmental levels of azoxystrobin (2 μg/L, 20 μg/L, and 200 μg/L) changes the behavior of male adult zebrafish. Herein, we evaluated behavioral response (locomotor, anxiety-like, and exploratory behaviors), histopathology, biochemical indicators, and gene expression in male adult zebrafish upon azoxystrobin exposure. The study showed that exposure to azoxystrobin for 42 days remarkably increased the locomotor ability of male zebrafish, resulted in anxiety-like behavior, and inhibited exploratory behavior. After treatment with 200 μg/L azoxystrobin, vasodilatation, and congestion were observed in male zebrafish brains. Exposure to 200 μg/L azoxystrobin notably elevated ROS level, MDA concentration, CAT activity, and AChE activity, while inhibiting SOD activity, GPx activity, ACh concentration, and DA concentration in male zebrafish brains. Moreover, the expression levels of genes related to the antioxidant, cholinergic, and dopaminergic systems were significantly changed. This suggests that azoxystrobin may interfere with the homeostasis of neurotransmitters by causing oxidative stress in male zebrafish brains, thus affecting the behavioral response of male zebrafish. [Display omitted] • Azoxystrobin exposure increased locomotor and anxiety-like behaviors of male zebrafish. • Azoxystrobin exposure inhibited exploratory behavior of male zebrafish. • Azoxystrobin exposure resulted in oxidative stress in male zebrafish brains. • Azoxystrobin exposure disturbed neurotransmitter homeostasis in male zebrafish brains. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Toxicología is the property of Asociacion Espanola de Toxicologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soil organisms are exposed to various pollutants during several generations. However standard toxicity tests are often based on exposure in only one generation. Research of multigenerational (MG) and transgenerational (TG) effects are still quite scarce, however evidence accumulates that effects observed in one generation can be significantly different in some of the following generations, with different effects observed. Some studies suggest adaptation to pollutants, while others report severe effects in following generations. Azoxystrobin is commonly used in the prevention and treatment of fungal diseases in a wide range of economically important crops. The main aim of this study was to assess the toxic effects of azoxystrobin (AZO) on F. candida over 3 generations through the application of biochemical and population level biomarkers. Results of reproduction tests showed a significant decrease in estimated EC 50 values, with EC 50 for F0 being estimated at 104.44 mg a.i. /kg D.W.soil and only 15.4 mg a.i. /kg D.W.soil for F1. In F1 a significant reduction in the number of juveniles was observed, and at AZO concentration of 50 mg a.i. /kg D.W and higher, F1 did not reproduce. Significant oxidative stress was observed in all generations, with increased SOD and lipid damage that slowly decreased in subsequent generations. Transgenerational effects were also observed, with a significantly reduced number of juveniles in F1 and significant oxidative stress and lipid damage in all generations. IBRv2 showed that F1 was most affected, followed by F0, and least affected was F3. When considering the whole body energy budget, F1 to F3 had significantly higher WBEB compared to F0, and a shift in proportion of energy reserves occurred in F1, where the proportion of lipids increased while protein decreased. Results of this research show that considering standard toxicity tests, risks for populations of soil organisms are possibly severely underestimated. Therefore, standard toxicity guidelines should be supplemented by multigenerational tests, when possible. [Display omitted] • Azoxystrobin caused oxidative stress in all generations • Estimated EC 50 (reproduction) significantly decreased in F1 compared to F0 • Extinction event occurred in F1 at higher azoxystrobin concentrations • Azoxystrobin caused multigenerational and transgenerational effects on F. candida • Transgenerational effects observed at environmentally relevant concentrations [ABSTRACT FROM AUTHOR]

Anthracnose, mainly caused by Colletotrichum truncatum , is a serious threat to soybean production worldwide. Azoxystrobin, a quinone outside inhibitor (QoI) fungicide, has long been frequently used in Thailand. As expected, its performance has decreased as the pathogen has developed fungicide resistance, mainly due to mutations in the target cytochrome b (cytb) gene. The substitution from glycine to alanine at codon 143 (G143A) is related to the azoxystrobin-completely resistant phenotype of C. truncatum. We thus used the G143A mutation as the reaction marker to develop a loop-mediated isothermal amplification (LAMP) method combined with hydroxynaphthol blue (HNB) for visual, simple, and rapid detection of azoxystrobin-resistant isolates of C. truncatum. Among four sets of primers designed, primer sets 1, 2, and 4 distinguished the isolate carrying the G143A mutation from wild-type isolate. Optimum conditions for the LAMP assay using primer set 4 were 63 °C for 80 min with a visible detection limit of 1 ng. Moreover, the LAMP assay was highly specific and accurate in tests of 125 isolates of C. truncatum from 13 fields in northern Thailand. This LAMP assay is highly efficient, simple, accurate for rapid field monitoring of azoxystrobin resistance in C. truncatum and implementing effective control measures. • Azoxystrobin resistance is mainly related to the G143A mutation in the cytb gene. • The G143A mutation was used as the marker for developing the LAMP assay. • The LAMP assay detected the azoxystrobin-resistant isolates within 80 min at 63 °C. • The detection limit of colorimetric LAMP was 1 ng of genomic DNA. • LAMP assay displayed high accuracy in tests of 125 isolates of C. truncatum. [ABSTRACT FROM AUTHOR]

Thailand is the leading producer and exporter of durians worldwide. Serious diseases in durians include root rot, stem rot, and fruit rot, which are caused by Phytophthora palmivora, P. nicotianae, and Pythium cucurbitacearum, respectively. Thai farmers have applied fungicides for more than 20 years to control rot, but it remains difficult to control. Thus, the monitoring of fungicide-resistance development in pathogens is important for disease management. Pathogens were isolated from naturally infected durians between 2016 and 2017 in southern Thailand. The sequences of the internal transcribed spacer (ITS) and 5.8S regions of rDNA were used for the identification of their species. Seventeen out of twenty isolates were confirmed to be P. palmivora. All the isolates were tested for mycelium-growth sensitivity to metalaxyl, azoxystrobin, and dimethomorph. The results showed that nine isolates were resistant to metalaxyl with the 50% effective concentration (EC50) higher than 100 mg L−1. By contrast, all the isolates were sensitive to both azoxystrobin and dimethomorph, with EC50 < 1 mg L−1. Metalaxyl-resistant isolates were not controlled (−25.6% to 22.2%) by the treatment of the detached leaves of ‘Monthong’ durian with 100 mg L−1 metalaxyl prior to inoculation, but all the metalaxyl-sensitive and moderately metalaxyl-resistant isolates were better controlled (33.0% to 62.6%). These results clearly indicate that metalaxyl-resistant strains are present in the populations of P. palmivora in Thailand.

In this work, the azoxystrobin removal in water by using a micro-size discharge array was investigated, and the removal efficiency can reach as high as 98.1% after 9 min plasma treatment as well as the energy utilization being only 0.73 g/(kW·h). Based on the relationship between the generation of gas bubbles and parameters of gas-liquid discharge, it was found that the variation of applied voltage, gas flow rate and initial solution temperature could cause particle number change, mass transfer rate change and the mass transfer time change, which significantly affected the practical applications at last. The experimental results indicated that when gas flow rate was 0.7 SLM (Standard Liter per Minute) and the initial solution temperature was 297 K with the applied voltage of 8 kV and discharge frequency of 6 kHz, the removal efficiency of azoxystrobin achieved maximum. Based on the analysis results of liquid mass spectrometry, the removal pathways of azoxystrobin were supposed by the decomposed by-products. Toxicity tests indicated that the decomposed products were safe and non-toxic. So, this study may reveal an azoxystrobin degradation mechanism and provide a safe, reliable and effective way for azoxystrobin degradation.

Background: Soil fumigation can change soil nutrient cycling processes by affecting soil beneficial microorganisms, which is a key issue for soil fertility. However, the effect of combined application of fumigant and fungicide on soil phosphorus (P) availability remains largely unclear. We investigated the effects of the fumigant chloropicrin (CP) and the fungicide azoxystrobin (AZO) on soil phosphatase activity and soil P fractions in ginger production using a 28-week pot experiment with six treatments: control (CK), a single application of AZO (AZO1), double applications of AZO (AZO2), CP-fumigated soil without AZO (CP), CP combined with AZO1 (CP + AZO1) and CP combined with AZO2 (CP + AZO2)., Results: AZO application alone significantly increased the soil labile P fractions (Resin-P + NaHCO 3 -Pi + NaOH-Pi) at 9 weeks after planting (WAP) but decreased the soil phosphatase activity at 28 WAP. CP fumigation significantly reduced the soil phosphatase activity but increased the proportions of soil labile P fractions (Resin-P + NaHCO 3 -Pi + NaHCO 3 -Po) to total P (TP) by 9.0-15.5% throughout the experiment. The combined application of CP and AZO had a synergistic effect on soil phosphatase activity and soil P fractions compared with a single application., Conclusion: Although AZO application and CP fumigation can increase soil available P in the short term, they might negatively affect soil fertility in the long run by inhibiting soil phosphatase activity. Soil microbial activities, especially microorganisms related to P cycling, may be responsible for the variations in soil P availability, but further research is needed. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)

Ultrasound as a green and efficient process gains special attention in wastewater treatment. The ultrasound-assisted degradation of azoxystrobin, methoxyfenozide, and propyzamide as widely used pesticides for vine treatment was investigated. A wide range of ultrasonic power (40 to 140 W) and a single frequency (20 kHz) were applied. Degradation experiments were carried out according to the parameters set by a central composite design (CCD) under response surface methodology (RSM) via JMP software. The treatment efficiency was quantified using degradation rates and hydrogen peroxide (H 2 O 2 ) measurements. Results indicated that the pesticide's degradation was negligible at 40 W but by increasing the power setting from 80 to 140 W, the degradation rate constants of azoxystrobin, methoxyfenozide, and propyzamide increased from 3.6 × 10 -2 min -1 to 0.2 min -1 , from 6.1 × 10 -2 min -1 to 0.3 min -1 , and from 3.1 × 10 -2 min -1 to 0.1 min -1 , respectively. The hydrogen peroxide (H 2 O 2 ) measurements confirmed this trend. Besides, electric energy per order of pollutant removal (EE/O) was also evaluated for the same treatment duration and results revealed that treatment conditions of 20 kHz and 140 W were the less energy-guzzling. Finally, profiles obtained with RSM illustrated linear degradation kinetics for azoxystrobin and propyzamide. Indeed, treatment efficiency increased when increasing both studied parameters. However, both linear and quadratic degradation kinetics occurred for methoxyfenozide degradation indicating a parameter threshold beyond which the trend is reversed. Overall, this study confirms the effectiveness of ultrasound for the degradation of pesticides in aqueous medium., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Aspergillus flavus infects peanuts and produces a mycotoxin called aflatoxin, a potent human carcinogen. In infected peanuts, it can also affect peanut seed quality by causing seed rot and reducing seed viability, resulting in low germination. In 2020, peanut seeds in Georgia had lower than expected germination and a high frequency of A. flavus contamination. A total of 76 Aspergillus isolates were collected from seven seed lots and their identity and in vitro reaction to QoI (quinone outside inhibitor) fungicide (azoxystrobin) were studied. The isolates were confirmed as A. flavus by morphological characteristics and a PCR (polymerase chain reaction)-based method using species-specific primers. In vitro, these isolates were tested for sensitivity to azoxystrobin. The mean EC50 values ranged from 0.12 to 297.22 μg/mL, suggesting that some isolates were resistant or tolerate to this fungicide. The sequences of cytochrome b gene from these isolates were compared and a single nucleotide mutation (36.8% isolates) was found as Cyt B G143A, which was associated with the total resistance to the QoIs. Another single mutation (15.8% isolates) was also observed as Cyt B F129L, which had been documented for QoI resistance. Therefore, a new major single mutation was detected in the A. flavus natural population in this study, and it might explain the cause of the bad seed quality in 2020. The high frequency of this new single nucleotide mutation exists in the natural population of A. flavus and results in the ineffectiveness of using azoxystrobin seed treatment. New seed treatment fungicides are needed.

Tea (Camellia sinensis), a globally cultivated beverage crop, is sensitive to drought, which can have an adverse effect on the yield and quality of tea. Azoxystrobin (AZ) is one kind of fungicide considered as an agent to relieve damage caused by stress. Initially, the response of tea plant to osmotic-gradient stress was evaluated using leaf disc assays with PEG-induced osmotic stress. The decline of the maximum quantum yield of PSII (Fv/Fm), actual photosynthetic efficiency of PS II (Y(II)), total chlorophylls, carotenoids, DPPH radical scavenging capacity, reducing power, total phenols, and the increase in MDA was observed in leaf discs treated with a gradient of PEG solutions (22.8, 33.2, 41.1% PEG, and blank). These results revealed that efficiency of photosystem II (PSII), photosynthetic pigments, and antioxidant ability in leaf discs were inhibited with an aggravated lipid peroxidation under PEG-induced osmotic stress, and indicated leaf disc assay with moderate PEG iso-osmotic condition would reflect a portion of tea plant response to drought stress. Therefore, the protective effect of AZ (0.125 and 1.25 g a.i. L−1) on tea plants suffering from drought was evaluated using leaf disc assays with 22.8% PEG iso-osmotic condition. Pretreatment of AZ (0.125 a.i. g L−1) reversed Fv/Fm, Y(II), DPPH radical scavenging capacity, and reducing power with reduced MDA in PEG-treated leaf discs, but photosynthetic pigments, total phenols, and ascorbate peroxidase activity were irresponsive to AZ. An Alleviated physiological damage in tea leaf with AZ applying was preliminarily revealed in this study. A Rapid screening of agents for tea plants against drought was developed to assist in the selection of protective agents.