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Peanut root rot, commonly referred to as rat tail or root rot, is caused by a range of Fusarium species. A strain of bacteria (named TG5) was isolated from crop rhizosphere soil in Mount Taishan, Shandong Province, China, through whole genome sequencing that TG5 was identified as Bacillus thuringiensis, which can specifically produce chloramphenicol, bacitracin, clarithromycin, lichen VK21A1 and bacitracin, with good biological control potential. Based on liquid chromatography tandem mass spectrometry metabonomics analysis and transcriptome conjoint analysis, the mechanism of TG5 and carbendazim inducing peanut plants to resist F. oxysporum stress was studied. In general, for peanut root rot caused by F. oxysporum, B. thuringiensis TG5 has greater advantages than carbendazim and is environmentally friendly. These findings provide new insights for peanut crop genetics and breeding, and for microbial pesticides to replace traditional highly toxic and highly polluting chemical pesticides. Based on the current background of agricultural green cycle and sustainable development, it has significant practical significance and broad application prospects. [ABSTRACT FROM AUTHOR]

Cucumber leaf spot (CLS), caused by Corynespora cassiicola, is a serious disease of greenhouse cucumbers. With frequent use of existing fungicides, C. cassiicola has developed resistance to some of them, with serious implications for the control of CLS in the field. With a lack of new fungicides, it is necessary to use existing fungicides for effective control. Therefore, this study monitored the resistance of C. cassiicola to three commonly used and effective fungicides, boscalid, trifloxystrobin, and carbendazim, from 2017 to 2021. The frequency of resistance to boscalid showed an increasing trend, and the highest frequency was 85.85% in 2020. The frequency of resistance to trifloxystrobin was greater than 85%, and resistance to carbendazim was maintained at 100%. Among these fungicides, strains with multiple resistance to boscalid, trifloxystrobin, and carbendazim were found, accounting for 32.00, 25.25, 33.33, 43.06, and 37.24%, respectively. Of the strains that were resistant to boscalid, 87% had CcSdh mutations, including seven genotypes: B-H278L/Y, B-I280V, C-N75S, C-S73P, D-D95E, and D-G109V. Also, six mutation patterns of the Ccß-tubulin gene were detected: E198A, F167Y, E198A&M163I, E198A&F167Y, M163I&F167Y, and E198A&F200C. Detection of mutations of the CcCytb gene in resistant strains showed that 98.8% were found to have only the G143A mutation. A total of 27 mutation combinations were found and divided into 14 groups for analysis. The resistance levels differed according to genotype. The development of genotypes showed a complex trend, increasing from 4 in 2017 to 13 in 2021 and varying by region. Multiple fungicide resistance is gradually increasing. Therefore, it is necessary to understand the types of mutations and the trend of resistance to guide the use of fungicides to achieve disease control. [ABSTRACT FROM AUTHOR]

Fusarium crown rot of wheat (FCR) is mainly caused by Fusarium pseudograminearum and is a major disease in the Huang-huai wheat growing region in China, leading to a potential yield loss. In order to evaluate the effect of pyraclostrobin on the growth of F. pseudograminearum and its control efficacy, the inhibitory activity of pyraclostrobin against the growth of F. pseudograminearum was studied, and field trials of pyraclostrobin against FCR was carried out. The results showed that pyraclostrobin had strong inhibitory effect on four growth stages of F. pseudograminearum. The EC50 value of pyraclostrobin to mycelial growth was 0.1168–10.3378 μg/mL with an average of (3.5348 ± 3.0044) μg/mL, and with the shortening of branch spacing, the branching number increased as well as the bending of the hyphal apex at the edge of the mycelia. The EC50 value of pyraclostrobin on conidial germination was 0.0052–0.2498 μg/mL with an average of (0.0782 ± 0.0504) μg/mL, and there was an increased chance that conidia will germinate from intermediate cells. The EC50 value of pyraclostrobin on germ tube elongation was 0.0244–0.0605 μg/mL, which could make the middle cells of the conidia to swell and become deformed, but the teratogenic effect on the germ tube was not obvious. Pyraclostrobin can delay conidia sporulation time and make the conidia cells enlarged and deformed. The EC50 value of sporulation was 0.0170–0.0225 μg/mL. The results of field trials in Xin'an County and Yichuan County of Luoyang City showed that compared with carbendazim, pyraclostrobin had higher control effect on FCR at the jointing stage and the filling stage, with the control effect being more than 50%. It also reduced the rate of white spikes of wheat at the milky stage, but the control effect of pyraclostrobin at the filling stage decreased. At the same time, pyraclostrobin soaking increased the plant height, stem girth and 1,000 grain weight of wheat. Pyraclostrobin could be used as an alternative fungicide in the integrated management of FCR. [ABSTRACT FROM AUTHOR]

BACKGROUND: Fusarium pseudograminearum is one of the dominant pathogens of Fusarium crown rot (FCR) worldwide. Unfortunately, no fungicides have yet been registered for the control of FCR in wheat in China. Pydiflumetofen, a new‐generation succinate dehydrogenase inhibitor, exhibits excellent inhibitory activity to Fusarium spp. A resistance risk assessment of F. pseudograminearum to pydiflumetofen and the resistance mechanism involved have not yet been investigated. RESULTS: The median effective concentration (EC50) value of 103 F. pseudograminearum isolates to pydiflumetofen was 0.0162 μg mL−1, and the sensitivity exhibited a unimodal distribution. Four resistant mutants were generated by fungicide adaption, which possessed similar or impaired fitness compared to corresponding parental isolates based on the results of mycelial growth, conidiation, conidium germination rate, and virulence determination. Pydiflumetofen showed strong positive cross‐resistance with cyclobutrifluram and fluopyram but no cross‐resistance with carbendazim, phenamacril, tebuconazole, fludioxonil, or pyraclostrobin. Sequence alignment revealed that pydiflumetofen‐resistant F. pseudograminearum mutants had two single‐point mutations of A83V or R86K in FpSdhC1. Molecular docking further confirmed that point mutation of A83V or R86K in FpSdhC1 could confer resistance of F. pseudograminearum to pydiflumetofen. CONCLUSION: Fusarium pseudograminearum shows an overall moderate risk of developing resistance to pydiflumetofen, and point mutation FpSdhC1A83V or FpSdhC1R86K could confer pydiflumetofen resistance in F. pseudograminearum. This study provided vital data for monitoring the emergence of resistance and developing resistance management strategies for pydiflumetofen. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The Fusarium head blight (FHB) caused by Fusarium graminearum is one of the most important diseases threatening wheat production in China. However, the triazole sterol 14α-demethylation inhibitor (DMI), prothioconazole, is known to exhibit high activity against F. graminearum. The current study indicated that three highly resistant laboratory mutants exhibited significantly (p < 0.05) altered growth and sporulation, although contrary to expectation, only one of the mutants exhibited reduced growth and sporulation, while the other two exhibited significant (p < 0.05) increases. Despite this, pathogenicity tests revealed that all of the mutants exhibited significantly (p < 0.05) reduced pathogenicity, indicating a substantial cost to fitness. Sequence analysis of the prothioconazole target protein, CYP51, of which F. graminearum has three homologues (FgCYP51A, FgCYP51B, and FgCYP51C), identified three mutations in the FgCYP51B sequence with a high likelihood of being associated with the observed resistance, as well as another three mutations in the FgCYP51B sequence, and two in the FgCYP51A sequence that are worthy of further investigation. Two of the prothioconazole-resistant mutants were also found to have several amino acid substitutions in their FgCYP51C sequences, and it was interesting to note that these two mutants exhibited significantly (p < 0.05) reduced pathogenicity compared to the other mutant. Expression analysis revealed that prothioconazole treatment (0.1 μg/mL) resulted in altered expression of all the FgCYP51 target genes, and that expression was also altered in the prothioconazole-resistant mutants compared to their wild-type parental isolates. Meanwhile, no evidence was found of any cross-resistance between prothioconazole and other commonly used fungicides, including carbendazim, pyraclostrobin, and fluazinam, as well as the triazole tebuconazole and the imidazole DMI prochloraz. Taken together, these results not only provide new insight into potential resistance mechanism in F. graminearum, and the biological characteristics associated with them, but also convincing evidence that prothioconazole can offer effective control of FHB. [ABSTRACT FROM AUTHOR]

Fluopyram, as a novel succinate dehydrogenase inhibitors (SDHIs) fungicide, was applied for controlling grey mould in China. In order to investigate the possible development of resistance development of Botrytis cinerea to fluopyram, Botrytis cinerea were collected from eight areas in Liaoning Province, and the sensitivities of these isolates were assessed by mycelium growth and the fitness and resistance mechanism of resistant isolates screened. The results showed that the sensitivity baseline of B. cinerea to fluopyram was (4.82 ± 1.49) μg/mL, and 5 low resistance isolates to fluopyram were detected. The fitness of resistant isolates showed a downward trend of several variables, such as mycelium growth, mycelium dry weight, sporulation and lesion diameter, which were significantly lower than those of sensitive isolates. Conidia germination did not differ significantly between sensitive and resistant isolates. There was no cross‐resistance between fluopyram and fludioxonil/boscalid/pyrimethanil/procymidone/carbendazim. The succinate dehydrogenase activity of resistant isolates was higher than that of sensitive isolates with fluopyram or not, and the inhibition of fluopyram on succinate dehydrogenase of sensitive isolates was greater than that of resistant isolates. Resistant isolates AS8 and AS14 carried the point mutation (N230I) in subunit B. These results provided that fluopyram belonged to a medium‐high resistance risk to B. cinerea. Information for managing resistance suggested that (1) the number of fluopyram applications should be limited to one per season and (2) fluopyram could be a valid alternative to fludioxonil, pyrimethanil, procymidone and carbendazim for the control of grey mould of tomato. [ABSTRACT FROM AUTHOR]

Fusarium pseudograminearum has been identified as a significant pathogen. It causes Fusarium crown rot (FCR), which occurs in several major wheat-producing areas in China. Chemical control is the primary measure with which to control this disease. In this study, transcriptome sequencing (RNA-Seq) was used to determine the different mechanisms of action of four frequently used fungicides including carbendazim, pyraclostrobin, tebuconazole, and phenamacril on F. pseudograminearum. In brief, 381, 1896, 842, and 814 differentially expressed genes (DEGs) were identified under the carbendazim, pyraclostrobin, tebuconazole, and phenamacril treatments, respectively. After the joint analysis, 67 common DEGs were obtained, and further functional analysis showed that the ABC transported pathway was significantly enriched. Moreover, FPSE_04130 (FER6) and FPSE_11895 (MDR1), two important ABC multidrug transporter genes whose expression levels simultaneously increased, were mined under the different treatments, which unambiguously demonstrated the common effects. In addition, Mfuzz clustering analysis and WGCNA analysis revealed that the core DEGs are involved in several critical pathways in each of the four treatment groups. Taken together, these genes may play a crucial function in the mechanisms of F. pseudograminearum's response to the fungicides stress. [ABSTRACT FROM AUTHOR]

In this study,the QuEChERSand high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS)was applied to determine thiophanate-methyl and its metabolite carbendazim residue in watercress. The average recoveries of both analytes in watercress ranged from 96.2% to 102.9% with relative standard deviation (RSD) less than 8.2%. The limit of quantification (LOQ)of method for both analytes was 0.01 mg/kg. The field trials were carried out in 2018 to monitor the residues of thiophanate-methyl and its metabolite in six main cultivation areas inwatercressof China. Thiophanate-methylrapidly dissipated and transformed to carbendazim under watercress field conditions with half-lives less than 2.12 d.Carbendazim also rapidly dissipated with half-lives of 2.76 and 3.77d at two experiment sites. The terminal residue of thiophanate-methyl,carbendazim and total thiophanate-methyl were lower than 14.5 mg/kg, 5.26 mg/kg and 13.3 mg/kg, respectively. In order to ensure the safety, the acute and chronic dietary intake risks were evaluated. The ADI%of thiophanate-methyl, carbendazim and total thiophanate-methyl ranged from 21.1% to 84.9% and their%ARfDranged from 2.1% to 19.2%, which suggested that thiophanate-methyl and carbendazim has a low risk for Chinese populations caused by application of thiophanate-methyl. [ABSTRACT FROM AUTHOR]

Peanut early leaf spot caused by Passalora arachidicola is serious fungal disease, which occurs in all production areas in China. Chemical control is the main method to prevent this disease. Nevertheless, it is easy to cause resistance, resurgence, residue problem (3R). Therefore, biological control is becoming the research hotspot for peanut early leaf spot control. 60 healthy peanut leaves were collected from major peanut production areas and were got for potential bacterial isolates. A total of 465 isolates were obtained. 22 strains showed differing levels of resistance against P. arachidicola. Among the antagonistic isolates, strain TL6 showed strongest inhibitory activity. It was identified as Bacillus amyloliquefaciens based on morphological characteristics, physiological and biochemical reactions as well as comparative analysis of its 16S rDNA sequence. The field control effect was above 69.17% after spraying the fermentation liquid of strain TL6. The field control effect of the strain TL6 fermentation liquid diluted 200 times and including the addition of 500 g/L carbendazim diluted 1000 times inhibited P. arachidicola by 81.33%. The combination of strain TL6 and carbendazim had a significant synergistic effect. Overall, strain TL6 showed promising potential commercial development and application in controlling peanut early leaf spot disease. [ABSTRACT FROM AUTHOR]

Carbendazim (CBDZ) is the most widely used fungicide in China. It is ubiquitous in environment and can induce oxidative stress in mammals, while data on occurrence of its metabolite in human urine are scarce, and the relationship between CBDZ and oxidative stress biomarkers (OSBs) in young children has not been examined. The aim of this study was to measure the concentrations of methyl 5-hydroxy-2-benzimidazolecarbamate (5-HBC, the main metabolite of CBDZ in urine) in 390 urine samples collected from 130 healthy young (< 6.6 years old) children from Shenzhen and Wuhan, in south and central China, respectively, and to evaluate the associations of 5-HBC with three selected OSBs (4-HNEMA, 8-OHG, and 8-OHdG, for lipid, RNA, and DNA, respectively). 5-HBC was found in 99.2% of the urine samples at concentrations ranging from below the method detection limit (< 0.005 ng/mL) to 10.9 ng/mL (median: 0.11 ng/mL). Moderate inter-day reproducibility was found for specific gravity-adjusted 5-HBC concentrations (intraclass correlation coefficient: 0.50). The urinary 5-HBC concentrations were significantly and positively associated with 4-HNEMA (p < 0.01). An interquartile range increase in urinary 5-HBC concentrations was associated with a 42.1% increase in 4-HNEMA, which implied that CBDZ exposure might be associated with lipid peroxidation in young children without occupational exposure. As far as we know, this pilot study is the first to report urinary 5-HBC and its associations with OSBs in children. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB), which is primarily caused by Fusarium graminearum, is a widespread and devastating disease of wheat. In the absence of resistant varieties, the control of FHB relies heavily on the application of fungicides, and the new generation SDHI fungicide, pydiflumetofen, has recently been registered in China for the control of FHB in wheat. The current study explored three genetically stable, highly resistant laboratory mutants (S2-4-2R, S27-3R, and S28-2R, with EC50 values of 25.10, 28.57, and 19.22 μg/mL, respectively) to investigate the potential risks associated with pydiflumetofen resistance. Although the mycelial growth of the mutants differed little compared to their parental isolates, the study found that the resistant mutants exhibited significantly reduced (p < 0.05) levels of sporulation and pathogenicity, which suggests a significant fitness cost associated with pydiflumetofen resistance in F. graminearum. Sequence analysis of the Sdh target protein identified numerous amino acid substitutions in the predicted sequences of the four subunits: FgSdhA, FgSdhB, FgSdhC, and FgSdhD. Indeed, the mutants were found to have a series of substitution in multiple subunits such that all three exhibited five identical changes, including Y182F in the FgSdhA subunit; H53Q, C90S, and A94V in FgSdhB; and S31F in FgSdhC. In addition, gene expression analysis revealed that all of the FgSdh genes had significantly altered expression (p < 0.05), particularly FgSdhA and FgdhC, which exhibited remarkably low levels of expression. However, the study found no evidence of cross-resistance between pydiflumetofen and tebuconazole, fludioxonil, prochloraz, fluazinam, carbendazim, pyraclostrobin, or difenoconazole, which indicates that these fungicides, either in rotation or combination with pydiflumetofen, could mitigate the risk of resistance emerging and provide ongoing control of FHB to ensure high and stable wheat yields. [ABSTRACT FROM AUTHOR]

Rice false smut (RFS), caused by Ustilaginoidea virens, is an important fungal disease of rice. In China, Methyl Benzimidazole Carbamates (MBCs), including carbendazim, are common fungicides used to control RFS and other rice diseases. In this study, resistance of U. virens to carbendazim was monitored for three consecutive years during 2018 to 2020. A total of 321 U. virens isolates collected from Jiangsu Province of China were tested for their sensitivity to carbendazim on PSA. The concentration at which mycelial growth is inhibited by 50% (EC50) of the carbendazim-sensitive isolates was 0.11 to 1.38 µg/mL, with a mean EC50 value of 0.66 μg/mL. High level of resistance to carbendazim was detected in 14 out of 321 isolates. The resistance was stable but associated with a fitness penalty. There was a statistically significant and moderate negative correlation (r= −0.74, p < 0.001) in sensitivity between carbendazim and diethofencarb. Analysis of the U. virens genome revealed two potential MBC targets, Uvβ1Tub and Uvβ2Tub, that putatively encode β-tubulin gene. The two β-tubulin genes in U. virens share 78% amino acid sequence identity, but their function in MBC sensitivity has been unclear. Both genes were identified and sequenced from U. virens sensitive and resistant isolates. It is known that mutations in the β2-tubulin gene have been shown to confer resistance to carbendazim in other fungi. However, no mutation was found in the Uvβ2Tub gene in either resistant or sensitive isolates. Variations including point mutations, non-sense mutations, codon mutations, and frameshift mutations were found in the Uvβ1Tub gene from the 14 carbendazim-resistant isolates, which have not been reported in other fungi before. Thus, these results indicated that variations of Uvβ1Tub result in the resistance to carbendazim in field isolates of Ustilaginoidea virens. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office 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.)

Top rot is a new fungal fruit disease in Rosa roxburghii production regions of southwest China. In this study, the pathogen of top rot disease in R. roxburghii fruits was firstly identified as Colletotrichum fructicola CXCDF-3 based on the pathogenicity, morphology, and multigene phylogenetic analysis. The biological property test results indicated that the optimal growth conditions of C. fructicola CXCDF-3 were 25 °C, pH 6.0~8.0, full light or darkness, D-(+) maltose, peptone, and PDA medium. Moreover, difenoconazole, tebuconazole, azoxystrobin, prothioconazole, thiophanate-methyl, prochloraz, carbendazim, and cyprodinil displayed superior toxicity activities to C. fructicola CXCDF-3 with EC50 values of 0.26, 0.64, 0.99, 2.15, 4.64, 4.89, 7.27, and 7.73 mg L−1, respectively. The field control efficacies of 80% tebuconazole water-dispersible granule (WG) 6000-fold liquid, 10% difenoconazole WG 5000-fold liquid, and 250 g/L azoxystrobin emulsifiable concentrate (SC) 1000-fold liquid against top rot disease of R. roxburghii fruits were 85.44%, 84.47%, and 83.50%, respectively. This study reports for the first time that the novel top rot disease in R. roxburghii is caused by C. fructicola and highlights that 80% tebuconazole WG, 10% difenoconazole WG, and 250 g/L azoxystrobin SC could be recommended for controlling top rot disease. [ABSTRACT FROM AUTHOR]

[Objective] Rice blast caused by Magnaporthe oryzae was one of the most destructive fungal diseases in rice production, which seriously threatens the safety of rice production in China. The study on the function of the transporter MoMfs2 encoding gene MoMFS2（MGG＿01301） in the growth, development and pathogenicity of M. oryzae provided a reference for the development of new fungicides. [Method] The deletion mutation of MoMFS2 was carried out using a knockout strategy and a series of biological phenotypes of the mutant were analyzed. [Result] The growth rate of the mutant was not different from that of the wild type on natural medium or synthetic medium, which indicated that MoMFS2 was not involved in the absorption and utilization of nutrition of M. oryzae. Moreover, the release rate of protoplast of the mutant was slow, the tolerance to cell wall stress congo red and SDS was significantly enhanced, which indicated that was involved in the response to cell wall stress and further speculated that it played an important role in cell wall integrity of M. oryzae. In addition, the mutant could not produce halo on CM medium containing Congo red and ABTS, and the secretion of extracellular laccase and peroxidase of the mutant was significantly decreased, indicating that MoMfs2 was involved in the secretion of extracellular laccase and peroxidase. On the other hand, the mutant was more sensitive to different types of fungicides (imidamide, carbendazim and pyrimethanil), which suggested that the mutant had reduced tolerance to fungicides, and speculated that MoMFS2 was involved in fungicidal efflux of M. oryzae. The pathogenicity of the mutant to rice and barley was no different from that of the wild type, indicating that MoMFS2 was not involved in pathogenicity of M. oryzae. [Conclusion] The transporter MoMfs2 was involved in the regulation of cell wall integrity, secretion of extracellular laccase and peroxidase and discharge of fungicides, but not in pathogenicity of M. oryzae. [ABSTRACT FROM AUTHOR]

[ Objective] The present paper aimed to identify the causal agents of Camptotheca acuminata leaf spot, and to test the inhibitory activity of different fungicides against the pathogen, so as to provide scientific evidence for the prevention and treatment of the leaf spot disease of C. acuminata. [ Method] The pathogen of the C. acuminata leaf spot was isolated by conventional tissue isolation method and subjected to pathogenicity test. Combining the morphology observation and rDNA-ITS sequence analysis, the pathogen was identified and the toxicity of 12 fungicides to the pathogen was determined by mycelial growth rate method.[ Result] A fungus was isolated from C. acuminata leaf spot in the Chinese Herb Garden of Guangxi Agricultural Vocational University, and the strain was named as XS-1. After pathogenicity test, morphological observation and molecular identification, it was confirmed that Corynespora cassiicola was the causal agent of the C. acuminate leaf spot, which is reported for the first time in China, and the disease was named as Corynespora leaf spot disease. The results of the inhibitory activity test showed that the selected 12 fungicides had a certain inhibitory effect on the growth of strain XS-1 mycelium. Among them, 20% difenoconazole and prochloraz ME had the strongest inhibitory effect with EC50 of 0.098 mg/L, followed by 20% penconazole EW, 50% carbendazim WP, 20% imazalil EW, 250 g/L propiconazole EC, 10% difenoconazole WG with EC50 of 0.3737, 0.4557, 0.4878, 0.5746 and 0.5956 mg/L, respectively.[ Conclusion] Based on pathogenicity test, morphology observation and rDNA-ITS sequence analysis, the pathogen causing C. acuminata leaf spot is identified as C. cassiicola. 20% difenoconazole and prochloraz ME, 20% penconazole EW, 50% carbendazim WP, 20% imazalil EW, 250 g/L propiconazole EC and 10% difenoconazole WG have strong inhibitory effect on the growth of strain XS-1 mycelium, and can be used as an important reference for the control of Corynespora leaf spot on C. acuminata in the field. [ABSTRACT FROM AUTHOR]

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui 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.)

Broussonetia papyrifera (L.) L'Hér. ex Vent. has considerable economic and ecological value and a long history of use in China. In this paper, root cuttings were used as the material to establish an efficient vegetative propagation of B. papyrifera. The results revealed that root segments with a diameter of 1.5~2.0 cm and a length of 20~30 cm were most suitable for shoot regeneration, as these segments had the highest adventitious shoot induction rates (93.3%), strongest adventitious shoots, and highest multiplication coefficients (7.07). With regard to the methods used for root burial, a horizontal burial at a depth of 1~3 cm yielded the best results, in this case, the adventitious shoot induction rate can reach 86.7%. The best substrate combination was perlite: peat: coconut chaff = 1:1:1 (v/v/v), wherein the adventitious shoot induction rate can reach 75.6%. The best sterilization method was mixing soil with carbendazim and soaking the root sections in carbendazim for 30 min, wherein the adventitious shoot induction rate can reach 77.8%. Adding 0.2 mg/L naphthaleneacetic acid (NAA) to 1/4 Hoagland nutrient solution significantly improved the rooting rate of adventitious shoots to 82.2%, and the survival rate of the acclimatized plants was more than 90.0%. [ABSTRACT FROM AUTHOR]

Rice blast caused by Magnaporthe oryzae in cultivated rice is a devastating fungal disease. The crop lost to rice blast is enough to feed more than 60 million people every year. At present, chemical control is still the primary measure to control rice blast. Pyraclostrobin is a methoxy acrylate fungicide, which has the characteristics of broad‐spectrum, high efficiency, environmental protection, and friendliness to non‐target organisms. Pyraclostrobin has been a good option for disease control in China. In this study, M. oryzae resistance to pyraclostrobin was evaluated. The pyraclostrobin‐resistant M. oryzae mutants were screened and the primary fitness parameters of resistant and sensitive strains were investigated. A total of nine pyraclostrobin‐resistant mutants were generated, which exhibited a mutation frequency of 3.46 × 10−4. The EC50 values of the mutants ranged from 2.2185 to 4.8946 μg/ml and resistant factors ranging from 467 to 4504. Biological character evaluations showed that all resistant mutants exhibited decreased fitness in mycelial growth rate, sporulation, and pathogenicity. Positive cross‐resistance was observed between pyraclostrobin and azoxystrobin or picoxystrobin, but not between pyraclostrobin and propiconazole or carbendazim. Sequence analysis of the partial fragment in cytb gene showed that there were two different point mutations in the nine resistant mutants. Seven mutants had a point mutation at position 427 (G to A transition), resulting in the conversion of glycine to serine (G143S). Two other mutants had a point mutation at position 428 (G to C transversion), resulting in the conversion of glycine to alanine (G143A). This mutation site is the main mechanism that has been reported to cause high resistance to QoI fungicides. Therefore, the G143A and G143S mutations found in this study could be the main reason for the mutant resistant to pyraclostrobin. [ABSTRACT FROM AUTHOR]

Wheat crown rot caused by Fusarium pseudograminearum has become an important soilborne disease and affects the quality and yield of wheat. In order to detect the sensitivity of F. pseudograminearum to fludioxonil in Henan Province, China, 105 isolates of F. pseudograminearum were collected from six cities in 2019. Sensitivity was determined by the mycelial growth rate method, then the methods of least-significant difference (LSD) and SPSS cluster were used for result analysis. The sensitivity of F. pseudograminearum to carbendazim and tebuconazole was determined and the correlation coefficient which existed between fludioxonil and the two fungicides, carbendazim and tebuconazole was analyzed. The results showed that the minimum inhibitory concentration (MIC) of fludioxonil was 0.240 0 μg/mL. The sensitivity frequency distribution was a continuous single peak curve, and the EC50 value ranged from 0.002 7 to 0.047 0 μg/mL. The average EC50 value of (0.026 3 ± 0.010 1) μg/mL, could be used as the sensitivity baseline of the pathogen to fludioxonil. The variance analysis results showed that the sensitivity of the different cities to fludioxonil was different, and the EC50 value ranged from 0.015 0 to 0.033 5 μg/mL. The maximum EC50 value of the isolate from Zhongmu County Zhengzhou City was 16.78 times bigger than the minimum value. Cluster analysis showed that there was no significant correlation between the sensitivity of isolates to fludioxonil and their geographical origin. The mean EC50 values of carbendazimand tebuconazole against the pathogens were (0.788 1 ± 0.315 3) μg/mL and (0.088 6 ± 0.145 3) μg/mL, respectively. There was no significant correlation between the sensitivity of the isolates to fludioxonil, carbendazim and tebuconazole. The results of greenhouse trials showed that the control efficacy of fludioxonil suspension seed coat agent could reach 58.00% (75.0 μg a.i/g) in 2020 and 63.69% (50.0 μg a.i/g) in 2021 when used to treat wheat as a seed dressing agent. The results of this study provide the basis for the rational use of fludioxonil in the control of wheat crown rot and provide information for monitoring the sensitivity of pathogenic fungi to fungicides. [ABSTRACT FROM AUTHOR]

BACKGROUND Carbendazim and epoxiconazole are widely applied to control anthracnose and sand bark fungal diseases in citrus. The residues of these two fungicides in citrus and their potential risk to consumers have generated much public concern. We therefore sought to investigate the dissipation, residue, and dietary risk assessment of carbendazim and epoxiconazole in citrus. RESULTS: The dissipation kinetics and residue levels of carbendazim and epoxiconazole in citrus under field conditions were measured using dispersive solid‐phase extraction and ultra‐high‐performance liquid chromatography–tandem mass spectrometry. The citrus samples were extracted with acetonitrile and purified by primary secondary amine sorbent. The mean recoveries of carbendazim and epoxiconazole ranged from 86.2 to 105.6% and relative standard deviations were ≤9.8%. The half‐lives of carbendazim and epoxiconazole in whole citrus ranged from 2.0 to 18.0 days. Hazard quotient (HQ) and risk quotient (RQ) models were applied to whole citrus for dietary exposure risk assessment based on the terminal residue test. Hazard quotients ranged from 0.066 to 0.134% and RQs from 18.48 to 82.12%. CONCLUSION: Carbendazim and epoxiconazole in citrus degraded rapidly following first‐order kinetics models. The dietary risk of exposure to both carbendazim and epoxiconazole through citrus, based on HQ and RQ, was acceptable for human consumption. This study indicates scientifically validated maximum residue limits in citrus, which are currently lacking for epoxiconazole in China. © 2021 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Wheat stem rot caused by Fusarium pseudograminearum has become the main disease in Huang-Huai wheat area, which poses a great threat to the stable and high yield of wheat. In order to detect the sensitivity to carbendazim of F. pseudograminearum causing wheat stembase rot in Henan Province, China, 90 isolates of were collected from 8 counties in 2019, the inhibitory activities of these isolates were determined by mycelial growth rate method. The results were analyzed by variance analysis and cluster analysis, and the sensitivity of tebuconazole and fludioxonil was also tested, to analyze the correlation efficient existed between carbendazim and the two fungicides, tebuconazole and fludioxonil. The results showed that the minimum inhibitory concentration of carbendazim was 2.4 μg/mL, the EC50 values ranged from 0.436 to 1.73 μg/mL, the maximum value was 3.98 times the minimum value, and the average EC50 value was (0.750 ± 0.291) μg/mL. The sensitivity frequency distribution map showed that although there were subpopulations with low sensitivity to multiple bacteria, there were still 61 strains tested within the corresponding main peak range, and the sensitivity frequency distribution was a continuous single peak curve, which could be used as the sensitivity baseline of the pathogen to carbendazim. The results of variance analysis showed that the sensitivity of the different county to carbendazim was less different, and the average EC50 value in different cities ranged from 0.604 μg/mL to 1.04 μg/mL, and the lowest and highest strains were Hongqi and Huixian from Xinxiang, respectively, with a difference of 1.72 times. The susceptibility of the strains to carbendazim was significantly different in the same city, and the difference of EC50 value was 3.98 times in Nanyang Neixiang. Cluster analysis showed that there was no significant correlation between the sensitivity of F. pseudograminearum to carbendazem in Henan Province and their geographical origin. There was no significant correlation between the sensitivity of wheat stem rot pathogen to carbendazim and its sensitivity to tebuconazole and fludioxonil. The results of greenhouse control showed that 50% carbendazim wettable powder can be used for wheat seed dressing treatment and the highest control efficacy on wheat stem rot up to 76.66% when the treatment dosage was 3.90 mg/g. The results of this study laid a theoretical foundation for the chemical control of wheat stem rot with carbendazim and provide important information for the sensitivity monitoring of pathogenic bacteria to fungicides. [ABSTRACT FROM AUTHOR]

Stem-end rot (SER) caused by Lasiodiplodia theobromae is an important disease of mango in China. Demethylation inhibitor (DMI) fungicides are widely used for disease control in mango orchards. The baseline sensitivity to difenoconazole of 138 L. theobromae isolates collected from mango in the field in 2019 was established by the mycelial growth rate method. The cross-resistance to six site-specific fungicides with different modes of action were investigated using 20 isolates randomly selected. The possible mechanism for L. theobromae resistance to difenoconazole was preliminarily determined through gene sequence alignment and quantitative real-time PCR analysis. The results showed that the EC50 values of 138 L. theobromae isolates to difenoconazole ranged from 0.01 to 13.72 µg/mL. The frequency of difenoconazole sensitivity formed a normal distribution curve when the outliers were excluded. Difenoconazole showed positive cross-resistance only with the DMI tebuconazole but not with non-DMI fungicides carbendazim, pyraclostrobin, fludioxonil, bromothalonil, or iprodione. Some multifungicide-resistant isolates of L. theobromae were found. Two amino acid substitutions (E209k and G207A) were found in the CYP51 protein, but they were unlikely to be related to the resistance phenotype. There was no alteration in the promoter region of the CYP51 gene. However, difenoconazole significantly increased the expression of the CYP51 gene in the resistant isolates compared to the susceptible isolates. These results are vital to develop effective mango disease management strategies to avoid the development of further resistance. [ABSTRACT FROM AUTHOR]

Peach is one of the popular and economically important fruit crops in China. Peach cultivation is hampered due to attacks of anthracnose disease, causing significant economic losses. Colletotrichum fructicola and Colletotrichum siamense belong to the Colletotrichum gloeosporioides species complex and are considered major pathogens of peach anthracnose. Application of different groups of fungicides is a routine approach for controlling this disease. However, fungicide resistance is a significant drawback in managing peach anthracnose nowadays. In this study, 39 isolates of C. fructicola and 41 isolates of C. siamense were collected from different locations in various provinces in China. The sensitivity of C. fructicola and C. siamense to some commonly used fungicides, i.e., carbendazim, iprodione, fluopyram, and propiconazole, was determined. All the isolates of C. fructicola collected from Guangdong province showed high resistance to carbendazim, whereas isolates collected from Guizhou province were sensitive. In C. siamense, isolates collected from Hebei province showed moderate resistance, while those from Shandong province were sensitive to carbendazim. On the other hand, all the isolates of C. fructicola and C. siamense showed high resistance to the dicarboximide (DCF) fungicide iprodione and succinate dehydrogenase inhibitor (SDHI) fungicide fluopyram. However, they are all sensitive to the demethylation inhibitor (DMI) fungicide propiconazole. Positive cross-resistance was observed between carbendazim and benomyl as they are members of the same methyl benzimidazole carbamate (MBC) group. While no correlation of sensitivity was observed between different groups of fungicides. No significant differences were found in each fitness parameter between carbendazim-resistant and sensitive isolates in both species. Molecular characterization of the β-tubulin 2 (TUB2) gene revealed that in C. fructicola, the E198A point mutation was the determinant for the high resistance to carbendazim, while the F200Y point mutation was linked with the moderate resistance to carbendazim in C. siamense. Based on the results of this study, DMI fungicides, e.g., propiconazole or prochloraz could be used to control peach anthracnose, especially at locations where the pathogens have already developed the resistance to carbendazim and other fungicides., Competing Interests: Declaration of competing interest The authors declare that they do not have any conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Fusarium graminearum is an important fungal pathogen causing Fusarium head blight (FHB) in wheat and other cereal crops worldwide. Due to lack of resistant wheat cultivars, FHB control mainly relies on application of chemical fungicides. Both fludioxonil (a phenylpyrrole compound) and phenamacril (a cyanoacrylate fungicide) have been registered for controlling FHB in China, however, fludioxonil-resistant isolates of F. graminearum have been detected in field. To evaluate the potential risk of dual resistance of F. graminearum to both compounds, fludioxonil and phenamacril dual resistant (DR) mutants of F. graminearum were obtained via fungicide domestication in laboratory. Result showed that resistance of the DR mutants to both fludioxonil and phenamacril were genetically stable after sub-cultured for ten generations or stored at 4 °C for 30 days on fungicide-free PDA. Cross-resistance assay showed that the DR mutants remain sensitive to other groups of fungicides, including carbendazim, tebuconazole, pydiflumetofen, and fluazinam. In addition, the DR mutants exhibited defects in mycelia growth, conidiation, mycotoxin deoxynivalenol (DON) production, and virulence Moreover, the DR mutants displayed increased sensitivity to osmotic stress. Sequencing results showed that amino acid point mutations S217L/T in the myosin I protein is responsible for phenamacril resistance in the DR mutants. Our results indicate that mutations leading to fludioxonil and phenamacril dual resistance could result in fitness cost for F. graminearum. Our results also suggest that the potential risk of F. graminearum developing resistance to both fludioxonil and phenamacril in field could be rather low, which provides scientific guidance in controlling FHB with fludioxonil and phenamacril. [Display omitted] • Laboratory induced fludioxonil and phenamacril double resistant (DR) mutants were obtained. • Double resistant (DR) mutants defect on fitness defined as mycelia growth, conidiation and virulence. • Osmotic stresses sensitivity and DON production were exhibited difference among DR mutants of F. graminearum. • The new type mutations were identified in DR mutants of F. graminearum. [ABSTRACT FROM AUTHOR]

Sclerotinia stem rot, caused by Sclerotinia sclerotiorum, is a devastating fungal disease in oilseed rape. Chemical control with fungicides is the primary method of controlling this disease. Metconazole is a demethylation inhibitor fungicide that has high activity against mycelial growth of phytopathogenic fungi. In this study, 119 isolates of S. sclerotiorum were collected from oilseed rape fields in different regions of Henan Province, China, in 2015 and 2016 prior to exposure to metconazole. The sensitivities of the S. sclerotiorum isolates to a range of concentrations of metconazole were determined based on mycelial growth inhibition in 90 cm Petri-dishes containing Potato dextrose Agar to which the fungicide was added. The 50% inhibition of mycelial growth (EC50) values of the S. sclerotiorum population to metconazole ranged from 0.0469 to 0.3912 µg mL− 1 and the mean EC50 value was 0.1875 ± 0.0058 µg mL− 1 (mean ± standard error). The frequency distribution range curve was unimodal with a narrow range. Spearman's rho (ρ) for the log10 of the EC50 values of 22 isolates of S. sclerotiorum between metconazole and carbendazim, dimethachlone, boscalid, fluazinam, and fludioxonil showed that there was no cross-resistance between metconazole and the other test fungicides. The results from this study provide important information for the control of Sclerotinia stem rot and sensitivity monitoring of S. sclerotiorum to metconazole in this area. [ABSTRACT FROM AUTHOR]

Colletotrichum fructicola is the major pathogen of anthracnose in tea-oil trees in China. Control of anthracnose in tea-oil trees mainly depends on the application of chemical fungicides such as carbendazim. However, the current sensitivity of C. fructicola isolates in tea-oil trees to carbendazim has not been reported. Here, we tested the sensitivity of 121 C. fructicola isolates collected from Guangdong, Guangxi, Guizhou, Hainan, Hunan, Jiangsu, and Jiangxi provinces in China to carbendazim. One hundred and ten isolates were sensitive to carbendazim, and 11 isolates were highly resistant to carbendazim. The growth rates, morphology, and pathogenicity of three resistant isolates were identical to those of three sensitive isolates, which indicates that these resistant isolates could form a resistant population under carbendazim application. These results suggest that carbendazim should not be the sole fungicide in control of anthracnose in tea-oil trees; other fungicides with different mechanisms of action or mixtures of fungicides could be considered. In addition, bioinformatics analysis identified two β-tubulin isotypes in C. fructicola : Cfβ 1 tub and Cfβ 2 tub . E198A mutation was discovered in the Cfβ 2 tub of three carbendazim-resistant isolates. We also investigated the functional roles of two β-tubulin isotypes. Cf Δ β 1 tub exhibited slightly increased sensitivity to carbendazim and normal phenotypes. Surprisingly, Cf Δ β 2 tub was highly resistant to carbendazim and showed a seriously decreased growth rate, conidial production, pathogenicity, and abnormal hyphae morphology. Promoter replacement mutant Cf Δ β 2 -2 ×β 1 showed partly restored phenotypes, but it was still highly resistant to carbendazim, which suggests that Cfβ 1 tub and Cfβ 2 tub are functionally interchangeable to a certain degree., Competing Interests: The author(s) declare no conflict of interest.

In this work, the toxicity of difenoconazole to Colletotrichum fructicola at different development stages and its indoor control efficacy were determined. The sensitive baseline of C. fructicola to difenoconazole at major pear cultivation areas in South China (Hubei, Anhui, Jiangxi, Jiangsu, Zhejiang and Fujian Province) was established. The conidia germination and germ tube elongation of six representative strains treated by difenoconazole were determined by spore germination rate method. And its indoor efficacy was tested using detached pear leaves. The sensitivity of 120 strains of C. fructicola to difenoconazole was determined by mycelial growth rate method. The results indicated that difenoconazole had high inhibitory activities against mycelial growth and germ tube elongation. However, the inhibition against conidia germination of C. fructicola was weak, with the average EC50 values of (0.33 ± 0.03) μg/mL, (2.61 ± 0.26) μg/mL and (29.87 ± 1.31) μg/mL, respectively. The protective and curative effects of 160 μg/mL difenoconazole to pear anthracnose were 92% and 79%, respectively. And those of 1 000 μg/mL carbendazim were 51% and 23%, respectively. 120 strains from major pear cultivation areas in South China were sensitive to difenoconazole, and the EC50 values were in the range of 0.27-1.12 μg/mL. The frequency curves of EC50 value was continuous and unimodal, and following the positive skewness distribution. Hence, the mean EC50 value (0.59 ± 0.02) μg/mL could be recognized as baseline sensitivities of C. fructicola to difenoconazole. The study laid the foundation for the evaluation and monitoring of the field resistance of C. fructicola to the difenoconazole, and provided a theoretical basis for the application of this fungicide to control pear anthracnose in the pear cultivation area. [ABSTRACT FROM AUTHOR]

Cucumber corynespora leaf spot, caused by Corynespora cassiicola , is the primary disease of cucumber leaves in greenhouses in China. Fludioxonil is a phenylpyrrole fungicide that inhibits C. cassiicola growth. We studied the sensitivity of 170 isolates of C. cassiicola to fludioxonil and evaluated resistance risk. All of the isolates were sensitive to fludioxonil. The EC 50 values ranged from 0.082 to 0.539 μg/mL with a mean of 0.207 ± 0.0053 μg/mL. Laboratory-created mutants with a high resistance factor to fludioxonil were genetically stable after 10 transfers and showed positive cross-resistance to iprodione and procymidone but not to azoxystrobin, carbendazim, pydiflumetofen, and prochloraz. There was no significant difference in mycelial growth and temperature adaptation between the mutant s and the sensitive isolates, except for pathogenicity and sporulation. The resistant isolates accumulated less glycerol than their parental isolates and were more sensitive to osmotic stress. The histidine kinase activity of the sensitive isolates was significantly inhibited compared to that of the resistant mutants. Sequence alignment of the histidine kinase gene CCos revealed that the mutants RTL4, RXM5, and RFS102 had point mutations at different sites that resulted in amino acid changes at G934E, S739F, and A825P in the CCos protein. The mutant RFS102 had an alanine deletion at site 824. After fludioxonil treatment, CCos expression by RFS20 was significantly lower than that of the parental isolate. Our findings demonstrate that C. cassiicola exhibits moderate resistance to fludioxonil. [Display omitted] • Fludioxonil has a strong inhibitory activity against Corynespora cassiicola. • The adaptability of the fludioxonil-resistant mutants in pathogenicity and osmotic stress decreased. • The resistance mechanism of fludioxonil is associated with the point mutation of CCos. [ABSTRACT FROM AUTHOR]

Cucumber leaf spot (CLS), caused by Corynespora cassiicola , is a serious disease of greenhouse cucumbers. With frequent use of existing fungicides, C. cassiicola has developed resistance to some of them, with serious implications for the control of CLS in the field. With a lack of new fungicides, it is necessary to use existing fungicides for effective control. Therefore, this study monitored the resistance of C. cassiicola to three commonly used and effective fungicides, boscalid, trifloxystrobin, and carbendazim, from 2017 to 2021. The frequency of resistance to boscalid showed an increasing trend, and the highest frequency was 85.85% in 2020. The frequency of resistance to trifloxystrobin was greater than 85%, and resistance to carbendazim was maintained at 100%. Among these fungicides, strains with multiple resistance to boscalid, trifloxystrobin, and carbendazim were found, accounting for 32.00, 25.25, 33.33, 43.06, and 37.24%, respectively. Of the strains that were resistant to boscalid, 87% had CcSdh mutations, including seven genotypes: B-H278L/Y, B-I280V, C-N75S, C-S73P, D-D95E, and D-G109V. Also, six mutation patterns of the Cc β -tubulin gene were detected: E198A, F167Y, E198A&M163I, E198A&F167Y, M163I&F167Y, and E198A&F200C. Detection of mutations of the CcCytb gene in resistant strains showed that 98.8% were found to have only the G143A mutation. A total of 27 mutation combinations were found and divided into 14 groups for analysis. The resistance levels differed according to genotype. The development of genotypes showed a complex trend, increasing from 4 in 2017 to 13 in 2021 and varying by region. Multiple fungicide resistance is gradually increasing. Therefore, it is necessary to understand the types of mutations and the trend of resistance to guide the use of fungicides to achieve disease control., Competing Interests: The author(s) declare no conflict of interest.

Gray mold caused by Botrytis cinerea has become an important limiting factor for tree peony production. Currently, chemical control is still the main means of managing the disease in China. The objective of this study was to test fungicides with different mechanisms of action in controlling B. cinerea on tree peony. The inhibitory efficacy of five fungicides on four asexual stages was measured in the petri dish containing culture medium amended with a tested fungicide at various concentrations. The results showed that carbendazim had the strongest inhibition effect against all four stages of B. cinerea, with the EC50 values of 0.1037, 0.0563, 0.5578, and 0.0797 mg·L-1, respectively. The inhibitory effect of diethofencarb was only slightly less than that of carbendazim on conidia production, germination, and germ tube elongation. The inhibitory effect of procymidone was second only to that of carbendazim on colony expansion. The results indicated that carbendazim and diethofencarb could be used as protective fungicides to spray in the early stage of disease occurrence to inhibit conidia germination and germ tube elongation, so as to reduce the infection rate of B. cinerea and prevent disease occurrence. Carbendazim, procymidone, and diethofencarb mainly inhibit the reinfection of B. cinerea by inhibiting the growth of mycelium and the production of conidia, so they could be used as control fungicides during the occurrence phase of the disease. [ABSTRACT FROM AUTHOR]

• NJC41 inhibited C. cassiicola mycelial growth and spore germination. • NJC41 showed high colonization ability in soybean pods. • NJC41 secreted antifungal phenethyl alcohol and competed for nutrients and space. • NJC41 reduced target spot symptoms in vivo. • The first method for the biocontrol of C. cassiicola in soybean is reported. Corynespora cassiicola is a hazardous fungal pathogen that causes target spot disease in soybean. Numerous resistant C. cassiicola strains have emerged during recent years, leading to uncontrolled spreads and enormous economic losses in several soybean production areas. For these reasons, new methods for the control of this pathogen are urgently needed. In this study, a new Meyerozyma caribbica strain, NJC41, was isolated from C. cassiicola -infected soybean plants in China and identified by ITS and LSU sequencing. NJC41 inhibited C. cassiicola mycelial growth, and showed high colonization ability in soybean pods, maintaining its population for one week. NJC41 produced antifungal phenethyl alcohol, which was detected at 44.6 μg/mL in NJC41 secretions, and competed for space and nutrients with C. cassiicola. Curative application of 1 × 109 cells/mL NJC41 reduced C. cassiicola symptoms by 47.1%, providing higher curative efficacy than commercial fungicide carbendazim (29.8% lesion length inhibition). This study reveals the first biocontrol method for the management of target spot disease in soybean. [ABSTRACT FROM AUTHOR]

• Dissipation of carbendazim in pickled cowpea was studied. • Half-life of carbendazim in pickled cowpea is less than 15 d. • Seven types of transformation products were detected using UPLC-HRMS/MS. • The main reactions in the pickled cowpea were identified as demethylation, hydroxylation and amination. • The biological toxicity and ecotoxicological information of the pickled cowpeas were evaluated. Carbendazim, a systemic fungicide, is one of the most commonly detected pesticides in cowpeas. Pickled cowpea is a fermented vegetable product with unique flavor favored in China. The dissipation and degradation of carbendazim were investigated in the pickled process. The degradation rate constant of carbendazim in pickled cowpeas was 0.9945 and the half-life of the carbendazim was 14.06 ± 0.82 d. Seven transformation products (TPs) were identified in the pickled process. Furthermore, the toxicity of some TPs show more harmful to three aquatic organisms (TP134) and rats (all the identified TPs) than carbendazim. And most of the TPs posed more development toxicity and mutagenicity than carbendazim. 4 out of 7 TPs were discovered in the real pickled cowpea samples. These results shed light on the degradation and biotransformation of the carbendazim in the pickled process, to better understand the potential health risk of pickled food and evaluate the environmental pollution. [ABSTRACT FROM AUTHOR]

This study was conducted to identify Fusarium spp. isolated from tomato plant in Iraq and China. A total of 12 isolates from Iraq (1-12) and four isolates from China (M1-M4) were used in this study. Based on Morphological characteristics (color, growth pattern, Macro and Micro-conidia shape) high differences between Fusarium isolates were found. Sensitivity test to the fungicide carbendazim revealed that one third of isolates(4/12) from Iraq had EC50 values over than 1000µg/ml indicated that many Iraqi isolates have developed resistance to carbendazim. Based on ITS sequences, Fusarium isolates were identified as follow, isolates 1, 3, 5, 6, 7, 10 were identified as Fusarium oxysporum, isolates 8, 11 as F. solani, isolates 12, M1 and M3 as F. moniliforme, isolates 2, M2 and M4 as F. proliferatum, F. chlamydosporum and F. kyushuense, respectively. [ABSTRACT FROM AUTHOR]

The rhizome of Belamcanda chinensis (belamcanda sinensis/Shegan) is an important traditional Chinese medicine, which is often used to treat lung diseases. However, soft rot disease seriously threatens the production of B. chinensis , causing its rhizomes to rot and the entire plant to die. Based on morphological characteristic and multigenic phylogenetic analyses of 16S rDNA, pel (pectate lyases encoding genes) and mdh (malic dehydrogenase encoding genes), the pathogenic isolates were identified as Dickeya fangzhongdai. One representative isolate SG-17 was selected for biological characteristics and pathogenicity tests analysis. The results showed that the optimum temperature and pH for SG-17 growth were 28 °C and pH 6, respectively. SG-17 caused typical soft rot symptoms on healthy B. chinensis plants, and produced symptoms of similar severity on Iris japonica (fringed iris) and Iris tectorum (iris), the other two species in Iridaceae family of economic and ornamental importance. Moreover, we also evaluated the impact of SG-17 on the contents of bioactive ingredients in B. chinensis rhizomes. The results show that the contents of tectorigenin and irigenin of B. chinensis rhizomes were increased significantly after infected with SG-17, while the contents of irisflorentin was decreased. As revealed by bactericides screen experiments, Ethylicin and Carbendazim · tetramethylthiuram disulfide exhibited good antibacterial activities, which could be used as the preferred agents for the control of soft rot of B. chinensis. As far as we know, this is the first report of Dickeya fangzhongdai causing soft rot on B. chinensis in the world. • This is the first report of soft rot disease of Belamcanda. chinensis caused by Dickeya fangzhongdai. • The optimum growth condition of D. fangzhongdai was at pH 6.0 and 28 °C. • Four bactericides showed good inhibition effects, among which Ethylicin showed significantly effective antibacterial ability. • The contents of tectorigenin and irigenin in rhizomes of infected by D. fanghzongdai were much higher than those in control groups. [ABSTRACT FROM AUTHOR]

Fusarium crown rot (FCR), primarily caused by Fusarium pseudograminearum , poses significant threats to cereal crops worldwide. Prothioconazole is a demethylation inhibitor (DMI) fungicide used to control FCR. However, the risk of resistance in F. pseudograminearum to prothioconazole has not yet been evaluated. In this study, the sensitivity of a total of 255 F. pseudograminearum strains obtained from Henan Province, China to prothioconazole were determined by the mycelial growth inhibition. The results showed that the effective concentration to 50% growth inhibition (EC 50) of these strains ranged from 0.4228 μg/mL to 2.5284 μg/mL, with a mean EC 50 value of 1.0692 ± 0.4527 μg/mL (mean ± SD). Thirty prothioconazole-resistant mutants were obtained out of six selected sensitive parental strains by means of fungicide taming. The resistant mutants exhibited defects in vegetative growth, conidia production, and pathogenicity on wheat seedlings compared to their parental strains. Under ion, cell wall, and temperature stress conditions but not osmotic stress, all the mutants exhibited decreased growth rates compared with their parental strains, which was consistent with the control treatment. Cross-resistance test showed that there was a cross-resistance relationship between prothioconazole and four DMI fungicides, including prochloraz, metconazole, tebuconazole and hexaconazole, but no cross-resistance was observed between prothioconazole and carbendazim, phenamacril, fludioxonil, or azoxystrobin. Although no site mutation occurred on Cyp51a and Cyp51b genes, the constitutive expression level of the Cyp51a gene was significantly increased in all mutants. After being treated with prothioconazole, the Cyp51a and Cyp51b genes were significantly increased in both the resistant mutants and their parents. These results suggested that the resistance to prothioconazole of the mutants may be attributed to the changes of the relative expression level of Cyp51a and Cyp51b genes. Taken together, these results could provide a theoretical basis for the scientific use of prothioconazole in the field and fungicide resistance management strategies. [Display omitted] • Baseline sensitivity of Fusarium pseudograminearum to prothioconazole was established. • The resistant mutants exhibited defects in vegetative growth, conidia production, and pathogenicity on wheat seedlings. • Under ion, cell wall, and temperature stress conditions, all the mutants exhibited decreased growth rates. • Prothioconazole have a cross-resistance with four DMI fungicides, and no cross-resistance with other fungicides. • The resistance of F. pseudograminearum to prothioconazole may be attributed to the expression of Cyp51a and Cyp51b genes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Seven fungicides with high detection frequencies (>85 %) were identified in three seasons. • Farmland density of controlled subbasin directly impact the spatial distribution of fungicides. • The reservoir affects fungicide transport, with retention effects in storage period. • Carbendazim is a substantial contributor to chronic ecological risk posed by fungicides. As an indispensable type of pesticide, fungicides have been somewhat neglected compared to insecticides and herbicides. Heavy fungicide application in agricultural regions may generate downstream ecological concerns via in-stream transport, and the reservoir complicates the process. Monitoring fungicide exposure and exploring reservoir effect on fungicide transport is the key to develop the downstream strategies of agricultural diffusion pollution control. Here, we investigated the exposure, spatiotemporal dynamics, and ecological risk of fungicides in a reservoir-regulated agricultural basin, located in the middle of the Yangtze River Basin, China. Seven fungicides were preliminarily identified and exhibited high detection frequencies (>85 %) in subsequent quantification of water samples from three sampling activities. The total concentration of fungicides ranged from 2.47 to 560.29 ng/L, 28.35 to 274.69 ng/L, and 13.61 to 146.968 ng/L in April, September, and November, respectively. Overall, the contamination levels of fungicides were in the ascending order of April < November < September. The spatial distribution of fungicides was closely associated with the dense of cultivated land, supporting its agricultural source. Furthermore, the reservoir plays a retention role in fungicides, alleviating ecological pressure downstream during the water storage period. Yet, due to the alternation of "source" and "sink" function of the reservoir, the contribution of Zijiang River to the fungicide load in the Yangtze River Basin still needs further attention. Although there is no acute risk posed by fungicides, even in the high-exposure scenario, the chronic ecological risk could not be ignored. Agricultural intensive regions, coupled with the reservoir, provide rather substantial chronic ecological concerns. Carbendazim has been designated as a priority pollutant that contributes significantly to cumulative chronic risk. Thus, we emphasize strengthening the supervision of fungicides in surface water and rationally restricting the use of carbendazim in agricultural operations. [ABSTRACT FROM AUTHOR]

The ascomycete fungus Sclerotinia sclerotiorum is a devastating necrotrophic plant pathogen with an unusually broad host range and worldwide distribution. The benzimidazole fungicide carbendazim has been widely used to control S. sclerotiorum in China for more than three decades and high levels of carbendazim resistance have been reported in eastern China. In this study, carbendazim sensitivity was assessed in a total of 5042 field isolates of S. sclerotiorum collected from different geographical regions of China from 2008 to 2013. Results showed that no carbendazim resistant isolates could be detected in northwestern and northeastern China. In 2013, 0.77% and 0.72% of the field isolates assayed were highly resistant to carbendazim in Hunan and Hubei provinces of central China, respectively. In Anhui province of eastern China, the frequencies of carbendazim resistance were 18.18%, 7.05% and 7.25% in 2008, 2011 and 2012, respectively. The decrease in frequency of carbendazim resistance in Anhui province from 2008 to 2012 was statistically significant ( P = 0.001). Nevertheless, no significant differences (P ≥ 0.16) were found in fitness parameters such as mycelial growth on PDA media, virulence to oilseed rape plants and oxalic acid production between carbendazim resistant and sensitive isolates. A negative cross resistance pattern was detected between carbendazim and diethofencarb. Mixture of carbendazim and diethofencarb (4:1) applied at 200 μg/mL provided 100% and 91.5% preventive efficacy against carbendazim resistant and sensitive isolates, respectively, and 87.1% and 81.7% curative efficacy against resistant and sensitive isolates, respectively. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) predominately caused by F. graminearum, is an economical devastating disease for grain cereal crops especially on wheat. The phenylpyrrole fungicide fludioxonil exhibits excellent activity against F. graminearum and has been registered to control FHB in China. In this study, 6 fludioxonil-resistant (FludR) isolates of F. graminearum were identified from 2910 isolates collected from wheat cultivated field in Jiang Su, An Hui and Henan province of China in 2020. The sensitivity assay showed that resistance factor (RF) of FludR isolates ranges from 170.73 to >1000. In comparison with fludioxonil-sensitive (FludS) isolates, all of FludR isolates showed fitness defects in terms of mycelial growth, conidiation and virulence. Under fludioxonil treatment condition, the glycerol accumulation was obviously increased in FludS isolates, but was slightly increased in FludR isolates. Four FludR isolates exhibited increased sensitivity to osmotic stresses. Moreover, there is no positive cross-resistance between fludioxonil and other fungicides including phenamacril, carbendazim and tebuconazole. When treated with fludioxonil, the phosphorylation level of Hog1 was significantly decreased in the four FludR isolates, which was in contrast to the observation in the FludS and two FludR isolates where phosphorylation level of Hog1 was increased. Sequencing assay showed that the mutations were identified in different domains in FgOS1, FgOS2 or FgOS4 in FludR isolates. This was first reported that biological and molecular characterizations of field isolates of F. graminearum resistant to fludioxonil. The results can provide scientific directions for controlling FHB using fludioxonil. [Display omitted] • Field fludioxonil-resistant isolates of F. graminearum were firstly identified in China. • Osmotic stresses sensitivity and phosphorylation level of Hog1 were exhibited difference among Fludioxonil-resistant isolates of F. graminearum. • The new type mutations were identified in Fludioxonil-resistant isolates of F. graminearum. [ABSTRACT FROM AUTHOR]

Botrytis cinerea , the fungal pathogen that causes grey mold in many crops, including the herbal medicinal plant ginseng (Panax ginseng), frequently exhibits multi-resistance. In this study, the sensitivity of 102 ginseng B. cinerea isolates collected from 11 ginseng growing regions in Jilin, Liaoning and Heilongjiang Provinces of China in 2018 and 2019 was examined. A total of 100%, 72.55% and 76.47% of the isolates were resistant to carbendazim (C), pyrimethanil (P) and iprodione (I), respectively. Four fungicide resistance patterns, including CRPRIR, CRPSIR, CRPRIS and CRPSIS, were identified, comprising 58.82%, 17.65%, 13.73% and 9.80%, respectively. The frequency and level of resistance of the isolates resistant to pyrimethanil and iprodione clearly varied among ginseng growing regions and lack significant cross-resistance. The geographic origins lacked any apparent correlation to pathogenicity, while the pathogenicity of isolates with the SC and M phenotypes was clearly higher than those with the SP phenotype. All the isolates resistant to carbendazim harbored a point mutation of E198A (Glu→Ala), E198V (Glu→Val), or E198K (Glu→Lys) at codon 198 in the β-tubulin gene, while isolates resistant to iprodione harbored a point mutation of I365S (Ile→Ser) or I365N (Ile→Asn) at codon 365, or point mutations of Q369P (Gln→Pro) + N373S (Asn→Ser) at codons 369 and 373 in the BcOS -1 gene. The patterns of point mutations in these genes closely correlated with the geographic origins, and the resistance of isolates that had the Q369P + N373S mutations was higher than those that had the I365S and I365N mutations. All these results provide a relatively clear understanding of the multi-resistance and molecular mechanism of B. cinerea isolates from ginseng growing regions in China. The variation in pathogenicity and the fungicide resistance of these isolates was revealed, which will help to establish a more effective strategy to control ginseng grey mold. • B. cinerea isolates from ginseng growing regions of China shown marked resistance to carbendazim, pyrimethanil and iprodione. • The pathogenicity of B. cinerea isolates was unrelated to their geographic origin but correlated with colonial phenotype. • E198A and E198V were predominated for carbendazim resistance, Q369P + N373S more resistant to iprodione than I365S and I365N. • The patterns of point mutations of B. cinerea isolates closely correlated with their geographic origins. [ABSTRACT FROM AUTHOR]

BACKGROUND Carbendazim has been used in the control of Fusarium head blight ( FHB) for more than 30 years in China. Thus, carbendazim-resistant ( CarR) populations of Gibberella zeae have developed in some areas. In this study, 9341 G. zeae isolates were collected from the ten main wheat-producing regions of China in the period from 2008 to 2012, and sensitivity to carbendazim was detected. RESULTS A high frequency of CarR isolates was observed in Zhejiang and Jiangsu provinces. CarR isolates were recovered from Anhui and Henan provinces in 2009 and 2012, respectively, but were not detected in the other six regions. Available ( F167Y, E198Q and F200Y) and newly developed ( E198L and E198K) allele-specific PCR assays were used to genotype field CarR isolates. The β-tubulin variants harbouring point mutation F167Y or E198Q accounted for >95% in CarR populations. Quantitative allele-specific real-time PCR assays were developed to determine the frequencies of five different β-tubulin variants present in populations of perithecia sampled from rice stubble. CONCLUSION CarR populations of G. zeae develop rapidly under the selection pressure of carbendazim. Real-time PCR assays detecting the resistance frequencies in populations of perithecia would provide useful information for FHB control and management of resistance. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: Fusarium head blight, one of the most damaging plant diseases in Jiangsu province of China, is a leading cause of economic loss and toxin accumulation in the crop, including nivalenol, deoxynivalenol and its acetylated derivatives. Disease control by carbendazim (MBC) has been applicated for many years, and the resistance frequency increased steadily. Furthermore, resistance may trigger toxin growth. Here, a total of 7261 isolates were collected throughout Jiangsu province from 2010 to 2012 to determine their sensitivity to MBC and trichothecene chemotypes. We studied the relevance between trichothecene chemotype and MBC-sensitivity, and found that the MBC-sensitive isolates occupied more NIV chemotype proportion up to date; 15-AcDON chemotype only existed in MBC-sensitive isolates; and most MBC-resistant isolates secreted 3-AcDON in chemotype. Besides, trichothecene production analyses indicated that MBC resistance increased 3-AcDON yield and percentage, especially site-directed mutants at codon 167 in the β2-tubulin gene. [Copyright &y& Elsevier]

Abstract: The adsorption and desorption of carbendazim and cadmium (Cd) in soils (burozem and phaeozem) typically distributed in northeastern China were investigated at two different temperatures, 25 and 40°C. The effects of interaction between carbendazim and Cd on their adsorption and desorption were also discussed. The results showed that the adsorption of carbendazim was exothermic with ΔHΘ values of −5.3kJ/mol for burozem and −33.6kJ/mol for phaeozem, while the adsorption of Cd was endothermic with ΔHΘ values of 43.2 and 37.4kJ/mol, respectively. Increasing the temperature from 25°C to 40°C could promote the desorption hysteresis of carbendazim, but decreased the desorption hysteresis of Cd. The coexistence of carbendazim and Cd promoted the adsorption of carbendazim but suppressed the adsorption of Cd and the effect was amplified as the temperature increased to 40°C. The adsorption amount of carbendazim at 25°C increased 11% for burozem and 4% for phaeozem respectively when the concentration of Cd was 50mg/L. This increased to 56% and 20% respectively when the temperature was increased to 40°C. When the concentration of carbendazim was 30mg/L, the amount of Cd adsorption decreased 13% for burozem and 5% for phaeozem at 25°C, and 33% and 14% at 40°C, respectively. [ABSTRACT FROM AUTHOR]

The article presents a study which uses point mutation to transform the ß-tubulin gene of Botrytis cinerea into Fusarium graminearum and identify if transformants were resistant to technical-grade carbendazim (MBC). It states that the Shenyang Academy of Chemistry and Industry in Shenyang, Liaoning Sheng, China has provided the MBC for testing. The results show that the gene could not manifest its effect in the F. graminearum due to the sensitivity of MBC transformants.

To provide scientific information for GAP of P. notoginseng and guiding the farmers and enterprises of Chinese medicine, dynamics of carbendazim residue in the Chinese medicinal herb, P. notoginseng and cultivated soil was studied at Wenshan County in 2008. The half lives of carbendazim in P. notoginseng were 5.92–6.82 day (soil), 6.71–6.77 day (fresh leaf), 3.29–3.93 day (fresh root), and 31.50–36.67 day (powder of the dry root) separately. Carbendazim residues in P. notoginseng were more stable during storage stage than growing stage. [ABSTRACT FROM AUTHOR]

Pyraoxystrobin is a new QoI fungicide developed in China. The present study was aimed at determining the baseline sensitivity of M. oryzae to pyraoxystrobin and investigating the potential resistance risk and resistance mechanism of pyraoxystrobin in M. oryzae. The results showed that the mean EC 50 of 109 M. oryzae isolates to pyraoxystrobin was 0.0094 μg/mL and the sensitivity exhibited a unimodal distribution. The established baseline sensitivity could provide critical data for monitoring sensitivity changes of M. oryzae to pyraoxystrobin in rice fields. The potential resistance risk was assessed by investigating the biological characteristics of the resistant mutants obtained by fungicide adaptation. The results indicated that the resistance risk of pyraoxystrobin in M. oryzae was medium to high with positive cross-resistance between pyraoxystrobin and azoxystrobin, but without cross resistance between pyraoxystrobin and carbendazim, isoprothiolane, and prochloraz. Further investigation revealed that the pyraoxystrobin-resistant mutants had a G143S mutation in the cyt b protein. Molecular docking confirmed that the G143S substitution conferred high resistance to pyraoxystrobin in M. oryzae. Collectively, the results of this study provided essential data for monitoring the emergence of resistance and developing resistance management strategies for pyraoxystrobin. [Display omitted] • Baseline sensitivity of M. oryzae to pyraoxystrobin was established. • The resistance risk of pyraoxystrobin in M. oryzae was medium to high. • The G143S mutation in cyt b conferred high resistance to pyraoxystrobin in M. oryzae. [ABSTRACT FROM AUTHOR]

The fungicide carbendazim and the insecticide chlorpyrifos are frequently used together to protect various fruit and vegetable crops in China. At high doses, carbendazim is a known carcinogen while chlorpyrifos has neurotoxic potential, but the combined toxicity of these two compounds has not been systematically investigated. In this study, we examined the separate and combined effects of these compounds on zebrafish embryonic development. The LC 50 values for carbendazim and chlorpyrifos at 96 h post-fertilization (hpf) were 0.89 mg/L and 3.83 mg/L, respectively. Carbendazim dose-dependently increased the spontaneous tail-wagging frequency of 24 hpf embryos, the hatching rate of 48 hpf embryos, and the mortality and deformity rate of 96 hpf embryos, while chlorpyrifos increased the heart rate of 48 hpf embryos as well as the mortality and deformity rate of 96 hpf embryos. Mixed exposure at an equipotent concentration ratio (Mix1) and at the ratio of maximum residue limits for typical fruits (apples) (Mix2) revealed significant synergistic effects on lethality at 96 hpf within the 0%–90% effect levels range. In contrast, there was an antagonistic effect of the equipotent concentration ratio on lethality in the 90%–100% concentration range, while the ratio at the maximum residue limits still showed a synergistic effect. Mix1 exhibited antagonism on hatching rate in the 0%–35% range and synergy in the 40%–100% range, while Mix2 had a synergistic effect on hatching rate in the 0%–35% range, an additive effect at 40%, and an antagonistic effect at >40%. Both mixtures had a synergistic effect on deformity rate over all concentration ranges. Carbendazim and chlorpyrifos demonstrate synergistic developmental toxicity, indicating that health and environmental risk assessments should be conducted for various combinations of these agents. • We examined carbendazim and chlorpyrifos toxicity in zebrafish embryos. • Both pesticides dose-dependently disrupted embryonic development. • In combination, toxicity was primarily synergistic across dose ranges and ratios. • Comprehensive health risk evaluation must consider these complex combined effects. [ABSTRACT FROM AUTHOR]

Although the carbendazim is widely used to manage spot blight in celery cultivation, information on residues identified is of interest. In this study, we examined the dissipation and residual amounts of carbendazim in celery and soil under different cultivation methods when using the suggested dose and ten times of that and the bioconcentration factor of carbendazim for celery. The results showed that when celery leaves were sprayed with the suggested dose, the half-lives in a celery field and greenhouse were 2.75 days and 3.29 days, respectively. When the soil matrix was sprayed with the recommended dose before cultivation, the half-lives of carbendazim residues were 16.86 days and 11.97 days. We also conducted a long-term dietary risk assessment using the corresponding criteria. The results showed that, in China, the use of carbendazim at a dose of 0.022 g/m 2 is safer and more reasonable when the harvest interval is 28 days., (© 2020. Springer Science+Business Media, LLC, part of Springer Nature.)

Fusarium head blight (FHB) is a worldwide devastating disease of wheat, caused primarily by species in the Fusarium graminearum (Fg) complex. In this study, we obtained 55 Fusarium isolates from wheat with FHB collected from seven provinces along the north of the Yangtze River. One additional phylogenetic species of Fg complex, Fusarium meridionale, was identified for the first time from China in addition to two known ones, Fusarium asiaticum and F.  graminearum. In addition, Fusarium acuminatum, distantly related to Fg complex, was for the first time identified in Northern China. Sensitivities of these isolates to carbendazim were examined and appeared to vary both within and between species. Mycotoxin genotype analyses indicated that F.  asiaticum isolates were potential 3-AcDON and NIV mycotoxin producers, while all F.  graminearum isolates might be 15-AcDON producers. These findings would provide useful information for developing management strategies for the control of FHB in Northern China. [ABSTRACT FROM AUTHOR]

Strawberry anthracnose caused by Colletotrichum species is an important disease that may cause significant economic losses. Based on multilocus sequence analyses and morphological characteristics, 64 isolates from strawberry anthracnose samples collected from nine Chinese provinces and municipalities were identified as three species: Colletotrichum fructicola (29 isolates), Colletotrichum siamense (23 isolates), and Colletotrichum nymphaeae (12 isolates). Isolates of C . siamense showed strong aggressiveness to fruit and leaves. Isolates of C . fructicola showed strong aggressiveness to crowns. Isolates of C . nymphaeae were weakly or not pathogenic to fruit, leaves, or crowns. Sensitivity to carbendazim was determined for a total of 75 isolates, including 11 previously preserved. Two isolates of C . siamense were highly resistant (HR) and 21 were moderately resistant (MR). Nine isolates of C . fructicola were sensitive (S), 24 were HR, and four were MR. All 15 isolates of C . nymphaeae were insensitive, and their mycelial growth was not completely inhibited on potato dextrose agar amended with 500 μg/ml carbendazim. Beta-tubulin ( TUB2 ) of representative isolates was amplified and sequenced, revealing a glutamic acid substituted by alanine at codon 198 in HR isolates of C . siamense and C . fructicola . MR isolates of C . siamense and C . fructicola had a point mutation at codon 200, causing a replacement of phenylalanine acid by tyrosine. No point mutation was detected at codons 50, 167, 198, 200, or 240 in TUB2 of C . nymphaeae insensitive isolates. Overall, this study revealed that C . fructicola was the dominant species causing anthracnose on strawberry and could improve the understanding of the management of fungicide resistance in Colletotrichum species on strawberry in China.