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Liu XY, Chaisiri C, Lin Y, Fu YP, Yin WX, Zhu FX, Li JB, Xiong B, Wu H, Xu A, Luo CX. Effective Management of Citrus Melanose Based on Combination of Ecofriendly Chemicals. Plant Dis 2023; 107:1172-1176. [PMID: 36222721 DOI: 10.1094/pdis-03-22-0513-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Citrus melanose, caused by the ascomycete fungus Diaporthe citri, is one of the most important diseases in China that affects not only the production but also the quality of citrus. In China, mancozeb is recommended to control melanose disease at the dose of 1.34 g/liter. However, it is widely applied in practice at the dose of 2.66 g/liter or even 4 g/liter, because reduced efficacy of the recommended dose was observed in regions severely damaged by melanose. In this study, some ecofriendly chemicals for melanose management were evaluated. First, the sensitivity to fungicides was screened in the laboratory based on the inhibition of mycelial growth and conidial germination of D. citri. Results showed that both quinone outside inhibitor (QoI) fungicides kresoxim-methyl and trifloxystrobin inhibited conidial germination of D. citri up to 100% at 0.1 μg/ml. The in vivo control efficacy on detached fruit indicated that treatments with elastic nanocopolymer film at 2 g/liter, mancozeb at 1 g/liter, and kresoxim-methyl at 0.1 g/liter significantly inhibited the infection process compared with the control treatment of mineral oil alone. In field trials, the efficacy of kresoxim-methyl at 0.1 g/liter and elastic nanocopolymer film at 2 g/liter mixed with mancozeb at 1 g/liter was equal to that of mancozeb at 2.66 g/liter. The use of mancozeb could be reduced greatly, and the newly developed fungicide combinations are more environmentally friendly due to the low toxicity of both QoI fungicides and elastic nanocopolymer film. The newly developed method with ecofriendly chemicals should play an important role in the management of citrus melanose in the future.
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Affiliation(s)
- X Y Liu
- Key Lab of Horticultural Plant Biology, Ministry of Education, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - C Chaisiri
- Key Lab of Horticultural Plant Biology, Ministry of Education, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Y Lin
- Hubei Key Laboratory of Plant Pathology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Y P Fu
- Hubei Key Laboratory of Plant Pathology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - W X Yin
- Hubei Key Laboratory of Plant Pathology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - F X Zhu
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - J B Li
- Nanfeng Citrus Research Institute, Nanfeng 344500, China
| | - B Xiong
- Nanfeng Citrus Research Institute, Nanfeng 344500, China
| | - H Wu
- Nanfeng Citrus Research Institute, Nanfeng 344500, China
| | - A Xu
- Nanfeng Citrus Research Institute, Nanfeng 344500, China
| | - C X Luo
- Key Lab of Horticultural Plant Biology, Ministry of Education, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Key Laboratory of Plant Pathology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
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Dong C, Hu J. Residue levels and dietary risk evaluation of prothioconazole-desthio and kresoxim-methyl in cucumbers after field application in twelve regions in China. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2023; 40:566-575. [PMID: 36976272 DOI: 10.1080/19440049.2023.2185459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
A commercial formulation called prothioconazole·kresoxim-methyl 50% water dispersible granule (WG), used to control the powdery mildew, is under registration for use on cucumbers. Therefore it is urgent to validate the reliability of the recommended good agricultural practices (GAP) conditions (187.5 g a.i. ha-1, three sprays with a 7-d interval, and a pre-harvest interval of 3 d) by conducting field trials in 12 regions in China, as required by national regulations, with a subsequent risk assessment. The residues of prothioconazole-desthio and kresoxim-methyl in field samples were determined using QuEChERS coupled with high-performance liquid chromatography - tandem mass spectrometry (HPLC-MS/MS). On the suggested pre-harvest interval (PHI, 3 d), the residual concentrations of prothioconazole-desthio (no maximum residue limit set in China) and kresoxim-methyl (maximum residue limit = 0.5 mg/kg) in cucumbers were 0.01-0.020 and 0.01-0.050 mg/kg, respectively. The acute risk quotients of prothioconazole-desthio in cucumbers were no higher than 0.079% for Chinese consumers. The chronic dietary risk quotient of kresoxim-methyl and of prothioconazole-desthio for different groups of consumers in China ranged from 2.3% to 5.3% and from 1.6% to 4.6%, respectively. Thus, prothioconazole·kresoxim-methyl 50% WG sprayed on cucumbers under the recommended GAP information can pose a negligible risk for Chinese consumers.
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Affiliation(s)
- Chao Dong
- Laboratory of Pesticide Residues and Environmental Toxicology, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, People's Republic of China
| | - Jiye Hu
- Laboratory of Pesticide Residues and Environmental Toxicology, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, People's Republic of China
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Vasilchenko AV, Poshvina DV, Semenov MV, Timofeev VN, Iashnikov AV, Stepanov AA, Pervushina AN, Vasilchenko AS. Triazoles and Strobilurin Mixture Affects Soil Microbial Community and Incidences of Wheat Diseases. Plants (Basel) 2023; 12:660. [PMID: 36771744 PMCID: PMC9919142 DOI: 10.3390/plants12030660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 01/18/2023] [Accepted: 01/30/2023] [Indexed: 06/18/2023]
Abstract
Pesticides are widely used in agriculture as a pest control strategy. Despite the benefits of pesticides on crop yields, the persistence of chemical residues in soil has an unintended impact on non-targeted microorganisms. In the present study, we evaluated the potential adverse effects of a mixture of fungicides (difenoconazole, epoxiconazole, and kresoxim-methyl) on soil fungal and bacterial communities, as well as the manifestation of wheat diseases. In the fungicide-treated soil, the Shannon indices of both fungal and bacterial communities decreased, whereas the Chao1 indices did not differ compared to the control soil. Among bacterial taxa, the relative abundances of Arthrobacter and Sphingomonas increased in fungicide-treated soil due to their ability to utilize fungicides and other toxic compounds. Rhizopus and plant-beneficial Chaetomium were the dominant fungal genera, with their prevalence increasing by 2-4 times in the fungicide-treated soil. The genus Fusarium, which includes phytopathogenic species, which are notably responsible for root rot, was the most abundant taxon in each of the two conditions but its relative abundance was two times lower in fungicide-treated soils, consistent with a lower level of disease incidence in plants. The prediction of metabolic pathways revealed that the soil bacterial community had a high potential for degrading various pollutants, and the soil fungal community was in a state of recovery after the application of quinone outside inhibitor (QoI) fungicides. Fungicide-treated soil was characterized by an increase in soil microbial carbon, compared with the control soil. Collectively, the obtained results suggest that the application of difenoconazole, epoxiconazole, and kresoxim-methyl is an effective approach for pest control that does not pose a hazard for the soil ecosystem in the short term. However, it is necessary to carry out additional sampling to take into account the spatio-temporal impact of this fungicide mixture on the functional properties of the soil.
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Affiliation(s)
- Anastasia V. Vasilchenko
- Laboratory of Antimicrobial Resistance, Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, 625003 Tyumen, Russia
| | - Darya V. Poshvina
- Laboratory of Antimicrobial Resistance, Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, 625003 Tyumen, Russia
| | - Mikhail V. Semenov
- Laboratory of Antimicrobial Resistance, Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, 625003 Tyumen, Russia
- Laboratory of Soil Carbon and Microbial Ecology, Dokuchaev Soil Science Institute, 119017 Moscow, Russia
| | - Vyacheslav N. Timofeev
- Scientific Research Institute of Agriculture for Northern Trans-Ural Region—Branch of Tyumen Scientific Centre SB RAS, 625003 Tyumen, Russia
| | - Alexandr V. Iashnikov
- Laboratory of Antimicrobial Resistance, Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, 625003 Tyumen, Russia
| | - Artyom A. Stepanov
- Laboratory of Antimicrobial Resistance, Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, 625003 Tyumen, Russia
| | - Arina N. Pervushina
- International Integrated Research Laboratory for the Study of Climate Change, Land Use and Biodiversity, Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, 625003 Tyumen, Russia
| | - Alexey S. Vasilchenko
- Laboratory of Antimicrobial Resistance, Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, 625003 Tyumen, Russia
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Man Y, Wang W, Mao L, Zhu L, Zhang Y, Zhang L, Jiang H, Liu X. Degradation of Kresoxim-Methyl in Different Soils: Kinetics, Identification of Transformation Products, and Pathways Using High-Resolution-Mass-Spectrometry-Based Suspect and Non-Target Screening Approaches. J Agric Food Chem 2022; 70:16146-16155. [PMID: 36515273 DOI: 10.1021/acs.jafc.2c07488] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
This study investigated the degradation of strobilurin fungicide kresoxim-methyl (KM) in three typical agricultural soils from China by aerobic and anaerobic degradation experiments, focusing on degradation kinetics of KM, identification of transformation products (TPs), and prediction of toxicity end points via in silico approaches. KM showed a pronounced biphasic degradation in different soils and could rapidly degrade, with DT50 of <3 days. Four TPs were identified by high-resolution mass spectrometry (HRMS), and three of them have never been reported before. Possible degradation pathways of KM in soil were proposed, including hydrolysis, oxidation, and reduction, and the main mechanism involved in the biodegradation of KM was the hydrolysis of methyl ester regardless of aerobic or anaerobic conditions. The results of toxicity evaluation indicated that some TPs are more toxic than KM and may have a developmental toxicity and mutagenicity, and further risk assessment should be carried out.
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Affiliation(s)
- Yanli Man
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China
| | - Wei Wang
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China
| | - Liangang Mao
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China
| | - Lizhen Zhu
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China
| | - Yanning Zhang
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China
| | - Lan Zhang
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China
| | - Hongyun Jiang
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China
| | - Xingang Liu
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China
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Martin PL, Krawczyk T, Pierce K, Thomas C, Khodadadi F, Aćimović SG, Peter KA. Fungicide Sensitivity of Colletotrichum Species Causing Bitter Rot of Apple in the Mid-Atlantic U.S.A. Plant Dis 2022; 106:549-563. [PMID: 34353127 DOI: 10.1094/pdis-06-21-1142-re] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Apple growers in the Mid-Atlantic region of the U.S.A. have reported increased losses to bitter rot of apple. We tested the hypothesis that this increase is because the Colletotrichum population has developed resistance to commonly used single-mode-of-action (single-MoA) fungicides. We screened 220 Colletotrichum isolates obtained from 38 apple orchards in the Mid-Atlantic region for resistance to 11 fungicides in Fungicide Resistance Action Committee (FRAC) groups 1, 7, 9, 11, 12, and 29. Eleven (5%) of these isolates were resistant to FRAC group 1 with confirmed β-tubulin E198A mutations, and two (<1%) were also resistant to FRAC group 11 with confirmed cytochrome-b G143A mutations. Such low frequencies of resistant isolates indicate that fungicide resistance is unlikely to be the cause of any regional increase in bitter rot. A subsample of isolates was subsequently tested in vitro for sensitivity to every single-MoA fungicide registered for apple in the Mid-Atlantic U.S.A. (22 fungicides; FRAC groups 1, 3, 7, 9, 11, 12, and 29), and 13 fungicides were tested in field trials. These fungicides varied widely in efficacy both within and between FRAC groups. Comparisons of results from our in vitro tests with results from our field trials and other field trials conducted across the eastern U.S.A. suggested that EC25 values (concentrations that reduce growth by 25%) are better predictors of fungicide efficacy in normal field conditions than EC50 values. We present these results as a guideline for choosing single-MoA fungicides for bitter rot control in the Mid-Atlantic U.S.A.
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Affiliation(s)
- Phillip L Martin
- Fruit Research and Extension Center, Department of Plant Pathology and Environmental Microbiology, The Pennsylvania State University, Biglerville, PA 17307
| | - Teresa Krawczyk
- Fruit Research and Extension Center, Department of Plant Pathology and Environmental Microbiology, The Pennsylvania State University, Biglerville, PA 17307
| | - Kristen Pierce
- Fruit Research and Extension Center, Department of Plant Pathology and Environmental Microbiology, The Pennsylvania State University, Biglerville, PA 17307
| | - Catherine Thomas
- Fruit Research and Extension Center, Department of Plant Pathology and Environmental Microbiology, The Pennsylvania State University, Biglerville, PA 17307
| | - Fatemeh Khodadadi
- Alson H. Smith Jr. Agricultural Research and Extension Center, School of Plant and Environmental Sciences, Virginia Polytechnic Institute and State University, Winchester, VA 22602
| | - Srđan G Aćimović
- Alson H. Smith Jr. Agricultural Research and Extension Center, School of Plant and Environmental Sciences, Virginia Polytechnic Institute and State University, Winchester, VA 22602
| | - Kari A Peter
- Fruit Research and Extension Center, Department of Plant Pathology and Environmental Microbiology, The Pennsylvania State University, Biglerville, PA 17307
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Noguerol-Pato R, Fernández-Cruz T, Sieiro-Sampedro T, González-Barreiro C, Cancho-Grande B, Cilla-García DA, García-Pastor M, Martínez-Soria MT, Sanz-Asensio J, Simal-Gándara J. Dissipation of Fungicide Residues during Winemaking and Their Effects on Fermentation and the Volatile Composition of Wines. J Agric Food Chem 2016; 64:1344-1354. [PMID: 26808836 DOI: 10.1021/acs.jafc.5b05187] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The effects of four fungicides commonly used for the control of fungal diseases in vines and grapes in the course of winemaking were tested. The concentration of fungicide residues was monitored throughout the process to establish their kinetics of dissipation. In all cases the percentages of dissipation were >68%, which shows the detoxificant effect of the winemaking process. On the other hand, the effect of the fungicide residues on the aroma composition of Tempranillo red wines was tested. To evaluate possible modifications on the aroma profile of wines, seven odorant series (ripe fruits, fresh fruits, lactic, floral, spicy, vinous, and herbaceous) were built from the odor activity values (OAVs) obtained for each volatile compound. Ripe fruits and fresh fruits were the major aromatic attributes in all Tempranillo red wines. These two odorant series registered the highest variations in their total OAVs with respect to the control wine, especially with the application of boscalid + kresoxim-methyl into vines, leading to a decrease in the ripe fruit and fresh fruit nuances of the resulting wines. Moreover, when the effect of these fungicides on the aroma of Tempranillo red wines was compared throughout two years (2012 and 2013), wines elaborated from grapes treated in the field with boscalid + kresoxim-methyl in 2013 displayed the highest variation in aroma profile with respect to control wine.
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Affiliation(s)
- Raquel Noguerol-Pato
- Nutrition and Bromatology Group, Analytical and Food Chemistry Department. Faculty of Food Science and Technology, University of Vigo , E-32004 Ourense, Spain
| | - Tania Fernández-Cruz
- Nutrition and Bromatology Group, Analytical and Food Chemistry Department. Faculty of Food Science and Technology, University of Vigo , E-32004 Ourense, Spain
| | - Thais Sieiro-Sampedro
- Nutrition and Bromatology Group, Analytical and Food Chemistry Department. Faculty of Food Science and Technology, University of Vigo , E-32004 Ourense, Spain
| | - Carmen González-Barreiro
- Nutrition and Bromatology Group, Analytical and Food Chemistry Department. Faculty of Food Science and Technology, University of Vigo , E-32004 Ourense, Spain
| | - Beatriz Cancho-Grande
- Nutrition and Bromatology Group, Analytical and Food Chemistry Department. Faculty of Food Science and Technology, University of Vigo , E-32004 Ourense, Spain
| | - Diego-Augusto Cilla-García
- Analytical Chemistry Group, Chemistry Department, Faculty of Sciences, University of La Rioja , E-26006 Logroño, Spain
| | - María García-Pastor
- Analytical Chemistry Group, Chemistry Department, Faculty of Sciences, University of La Rioja , E-26006 Logroño, Spain
| | - María-Teresa Martínez-Soria
- Analytical Chemistry Group, Chemistry Department, Faculty of Sciences, University of La Rioja , E-26006 Logroño, Spain
| | - Jesús Sanz-Asensio
- Analytical Chemistry Group, Chemistry Department, Faculty of Sciences, University of La Rioja , E-26006 Logroño, Spain
| | - Jesús Simal-Gándara
- Nutrition and Bromatology Group, Analytical and Food Chemistry Department. Faculty of Food Science and Technology, University of Vigo , E-32004 Ourense, Spain
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Kim E, Moon JK, Choi H, Kim JH. Probabilistic Exposure Assessment for Applicators during Treatment of the Fungicide Kresoxim-methyl on an Apple Orchard by a Speed Sprayer. J Agric Food Chem 2015; 63:10366-10371. [PMID: 26492351 DOI: 10.1021/acs.jafc.5b03217] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Probabilistic exposure and risk assessment of kresoxim-methyl were conducted for agricultural applicators during preparation of spray suspension and application with a speed sprayer on an apple orchard. The preparation and application of 1000 L of spray suspension were repeated 30 times. Several exposure matrices, including patches, cotton gloves, socks, masks, and XAD-2 resin, were used to measure the potential exposure for workers. The analytical methods were fully validated to guarantee the precision and accuracy of analysis. The exposure amount on hands for mixer/loader was 0.7 mg [95% confidence interval (CI) from 0.02 to 2.4], taking 0.0005% (95% CI from 1.2 × 10(-5) to 0.001) of total prepared active ingredient. During application of kresoxim-methyl, the amount of dermal exposure was 17.5 mg (95% CI from 9.3 to 28.9), corresponding to 0.010% (95% CI from 0.006 to 0.017) of total applied active ingredient. The major exposure parts of the body were thighs and shins, with correlation coefficients of 0.53 and 0.43, respectively. The inhalation exposure during application were estimated as 6.8 ng (95% CI from 0.4 to 17.0), being 0.04% (95% CI from 0.004 to 0.06) of the dermal exposure. The calculated absorbable quantities of exposures for mixer/loader and applicator were 2.1 × 10(-4) mg/day (95% CI from 5.0 × 10(-6) to 7.2 × 10(-4)) and 2.3 mg/day (95% CI from 1.2 to 3.8), respectively. For risk assessment, the margin of safety of all working activities was much higher than 1, indicating that the possibility of risk to kresoxim-methyl was unlikely.
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Affiliation(s)
- Eunhye Kim
- Department of Agricultural Biotechnology, Seoul National University , Seoul 151-742, Republic of Korea
| | - Joon-Kwan Moon
- Department of Plant Life and Environmental Sciences, Hankyong National University , Ansung 456-749, Republic of Korea
| | - Hoon Choi
- Division of Food and Environmental Sciences, Wonkwang University , Iksan 570-749, Republic of Korea
| | - Jeong-Han Kim
- Department of Agricultural Biotechnology, Seoul National University , Seoul 151-742, Republic of Korea
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Stević M, Tamaš N, Miletić N, Vukša P. Different toxicity of the strobilurin fungicides kresoxim-methyl and trifloxistrobin to Venturia inaequalis isolates from Serbia. J Environ Sci Health B 2015; 50:633-637. [PMID: 26079336 DOI: 10.1080/03601234.2015.1038952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Sensitivity of monosporial isolates of V. inaequalis, originated from apple orchards previously exposed (commercial and experimental) and those originated from location where fungicides had never been used (wild type), to strobilurin fungicides kresoxim-methyl and trifloxistrobin was investigated in this study. The experiments were carried out in laboratory using in vitro and in vivo methods. Mycelia growth inhibition on PDA medium with kresoxim-methyl and trifloxistrobin was monitored and sensitivity parameters (EC50 values) were determined using probit analysis. The isolates sensitivity in vivo was tested on apple seedlings using inoculation method. The EC50 values were ranging from 0.066-2.033 and 0.011-0.323 µg mL(-1) for kresoxim-methyl and trifloxistrobin, respectively. The wild type of isolates showed a normal susceptibility to kresoxim-methyl and trifloxistrobin, while isolates originated from experimental and commercial orchard where those fungicides had been used extensively, showed significantly lower sensitivity to the both strobilurin fungicides. The isolate that showed the resistance to kresoxim-methyl and trifloxistrobin in vitro test, also showed reduced sensitivity in vivo test and could not been controlled satisfactory by fungicide concentrations that are commercially used, as well as by double higher, after apple seedlings inoculation.
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Affiliation(s)
- Milan Stević
- a Faculty of Agriculture, University of Belgrade , Belgrade-Zemun , Serbia
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