[Objective] The aim was to research prevention effects of 25％ azoxys trobin suspending agent to cucumber downy mildew.[Method] The test,including control group and four treatment groups with 450,600,and 750 g/hm2 25...[Objective] The aim was to research prevention effects of 25％ azoxys trobin suspending agent to cucumber downy mildew.[Method] The test,including control group and four treatment groups with 450,600,and 750 g/hm2 25％ azoxystrobin suspending agents,and 80％ mancozeb wettable powder,was carried out in 2012 and 2013 consecutively to test the prevention effects of 25％ azoxystrobin suspending agent to cucumber downy mildew.[Result] The prevention effects were significant of 25％ azoxystrobin suspending agent to cucumber downy mildew in the range of 70.0％-83.6％,and it is recommended 25％ azoxystrobin suspending agent at 600 g/hm2 be spread before plants diseased or in initial stage.In the whole stage,it was spread once every 7 d,totaling 3 times.[Conclusion] The research provides references for wide application of 25％ azoxystrobin suspending agent in production.展开更多
The hydrolysis reaction of azoxystrobin in a methanol solution was studied, obtaining a novel compound 3,3-dimethoxy-2-（2-（6-methoxy pyrimidin-4-yloxy）phenyl） propanoic acid. The hydrolysis reaction may be helpful...The hydrolysis reaction of azoxystrobin in a methanol solution was studied, obtaining a novel compound 3,3-dimethoxy-2-（2-（6-methoxy pyrimidin-4-yloxy）phenyl） propanoic acid. The hydrolysis reaction may be helpful to explaining the degradation mechanism of azoxystrobin in soil or plant, which is also a method for further study on metabolism in vitro. The crystal structure was confirmed by 1H NMR and MS and determined by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 8.5662（2）, b = 10.5074（6）, c = 10.9849（7）, α = 62.8370（10）, β = 73.2170（10）, γ = 73.3100（2）o, C16H18N2O6, Mr = 334.32, V = 828.09（9）3, Z = 2, Dc = 1.341 g/cm3, F（000） = 352, μ = 0.104 mm-1, S = 1.075, the final R = 0.0665 and wR = 0.1593 for 2083 observed reflections with I 2σ（I） and 220 variable parameters. The crystal analysis shows that the hydrolysis product contains two rings, and a one- dimensional chain structure is formed via the intermolecular hydrogen bond O（1）–H（101）···N（2）.展开更多
Analytical method for the residues of strobilurins azoxystrobin and pyraclostrobin in blueberries was developed. Fungicide residues were determined by solid-phase microextraction (SPME) cou-pled to gas chromatography ...Analytical method for the residues of strobilurins azoxystrobin and pyraclostrobin in blueberries was developed. Fungicide residues were determined by solid-phase microextraction (SPME) cou-pled to gas chromatography with micro-electron capture detector. The effect of pH values and fiber coatings were studied. The SPME fiber coating selected was 100 μm PDMS. The method is selective with adequate precision and high accuracy and sensitivity. Recoveries ranged within the 100% - 106% range for azoxystrobin, and 96% - 106% range for pyraclostrobin;and detection and quantification limits were 2.0 and 6.0 μg/kg for azoxystrobin, and 26.0 and 86.0 μg/kg for py-raclostrobin, respectively. Statistical parameters indicated the occurrence of matrix effect;con-sequently calibration was performed on spiked samples. Degradation of azoxystrobin and pyra-clostrobin was studied in blueberry fields located in Concordia, Argentina, with fruits from Emerald and Jewel varieties. The degradation of these fungicides in both blueberry varieties studied followed a first order rate kinetics, and the half-life for azoxystrobin was 11.6 and 17.8 days for Emerald and Jewel cultivars;and for pyraclostrobin was 5.5 and 8.0 days, respectively.展开更多
Azoxystrobin acts as an inhibitor of electron transport by binding to the Qo center of cytochrome b （cyt b）. Resistance to azoxystrobin was usually caused by the point mutation of cyt b gene or by the induction of a...Azoxystrobin acts as an inhibitor of electron transport by binding to the Qo center of cytochrome b （cyt b）. Resistance to azoxystrobin was usually caused by the point mutation of cyt b gene or by the induction of alternative respiration. Oxygen consumption test for mycelia of Colletotrichum capsici showed that azoxystrobin inhibited mycelial respiration within 12 h; however, as time went on, the respiration of the mycelia recovered when the mycelia were treated with azoxystrobin and salicylhydroxamic acid （SHAM, a known inhibitor of alternative respiration）, and the oxygen consumption of the mycelia could not be inhibited. Meanwhile, cytochrome b （cyt b） gene expression increased with the recovery of mycelial respiration. The increased cyt b gene expression might play a role in the development of resistance to azoxystrobin in C. capsici.展开更多
An effective broad-spectrum fungicide,azoxystrobin(AZ),has been widely detected in aquatic ecosystems,potentially affecting the growth of aquatic microorganisms.In the present study,the eukaryotic alga Monoraphidium s...An effective broad-spectrum fungicide,azoxystrobin(AZ),has been widely detected in aquatic ecosystems,potentially affecting the growth of aquatic microorganisms.In the present study,the eukaryotic alga Monoraphidium sp.and the cyanobacterium Pseudanabaena sp.were exposed to AZ for 7 days.Our results showed that 0.2–0.5 mg/L concentrations of AZ slightly inhibited the growth of Monoraphidium sp.but stimulated Pseudanabaena sp.growth.Meanwhile,AZ treatment effectively increased the secretion of total organic carbon(TOC)in the culture media of the two species,and this phenomenon was also found in a freshwater microcosm experiment(containing the natural microbial community).We attempted to assess the effect of AZ on the function of aquatic microbial communities through metabolomic analysis and further explore the potential risks of this compound.The metabonomic profiles of the microcosm indicated that the most varied metabolites after AZ treatment were related to the citrate cycle(TCA),fatty acid biosynthesis and purine metabolism.We thereby inferred that the microbial community increased extracellular secretions by adjusting metabolic pathways,which might be a stress response to reduce AZ toxicity.Our results provide an important theoretical basis for further study of fungicide stress responses in aquatic microcosm microbial communities,as well as a good start for further explorations of AZ detoxification mechanisms,which will be valuable for the evaluation of AZ environmental risk.展开更多
Background:Cultivation of red dragon fruit(Hylocereus polyrhizus)in Indonesian orchards is hampered by anthracnose and stem canker.A mixture of azoxystrobin 200 g/L+difenoconazole 125 g/L is recommended in supporting ...Background:Cultivation of red dragon fruit(Hylocereus polyrhizus)in Indonesian orchards is hampered by anthracnose and stem canker.A mixture of azoxystrobin 200 g/L+difenoconazole 125 g/L is recommended in supporting the obligated integrated pest management.For the consumer safety,dietary intake of the residues from fresh edible part should be assessed;therefore,information on correct dissipation pattern of the applied pesticide is required.Materials and Methods:Field residue trials in Indonesian highland(West Java)and coastal area(Special Region of Yogyakarta)were done at recommended dose was 0.151 kg ai/ha azoxystrobin and 0.094 kg ai/ha difenoconazole,three times at 10 days interval.Whole fruit samples were collected at 70%-100%ripeness at−1,0,1,3,7,10,and 14 days after last application,processed and determined its residue as soon as possible.Result and Discussion:Photoisomerization of azoxystrobin was observed at Day 0,especially in coastal area;however,it has been dissipated to below lowest validated level in the following day.At Day 0,3%-5%of the deposited azoxystrobin and difenoconazole penetrate into the flesh;however,most residues(95%-97%)were retained in peel,and dissipated in prolonged day.The dissipation pattern was non-linear.The dissipation data were better fit with bi-exponential double-first-order in parallel than single first-order kinetics model.The DT50 of both azoxystrobin and difenoconazole was 3 days.At harvest time,seventh day,only azoxystrobin residue was detected in flesh at 0.006 mg/kg;therefore,the long-term dietary risk was 0 per cent acceptable daily intake.Conclusion:Fresh red dragon fruit is safe to consume.展开更多
文摘[Objective] The aim was to research prevention effects of 25％ azoxys trobin suspending agent to cucumber downy mildew.[Method] The test,including control group and four treatment groups with 450,600,and 750 g/hm2 25％ azoxystrobin suspending agents,and 80％ mancozeb wettable powder,was carried out in 2012 and 2013 consecutively to test the prevention effects of 25％ azoxystrobin suspending agent to cucumber downy mildew.[Result] The prevention effects were significant of 25％ azoxystrobin suspending agent to cucumber downy mildew in the range of 70.0％-83.6％,and it is recommended 25％ azoxystrobin suspending agent at 600 g/hm2 be spread before plants diseased or in initial stage.In the whole stage,it was spread once every 7 d,totaling 3 times.[Conclusion] The research provides references for wide application of 25％ azoxystrobin suspending agent in production.
基金Supported by the Science and Technology Project of Zhejiang Province (Nos. 2008C02007-3 and 2009C21014)
文摘The hydrolysis reaction of azoxystrobin in a methanol solution was studied, obtaining a novel compound 3,3-dimethoxy-2-（2-（6-methoxy pyrimidin-4-yloxy）phenyl） propanoic acid. The hydrolysis reaction may be helpful to explaining the degradation mechanism of azoxystrobin in soil or plant, which is also a method for further study on metabolism in vitro. The crystal structure was confirmed by 1H NMR and MS and determined by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 8.5662（2）, b = 10.5074（6）, c = 10.9849（7）, α = 62.8370（10）, β = 73.2170（10）, γ = 73.3100（2）o, C16H18N2O6, Mr = 334.32, V = 828.09（9）3, Z = 2, Dc = 1.341 g/cm3, F（000） = 352, μ = 0.104 mm-1, S = 1.075, the final R = 0.0665 and wR = 0.1593 for 2083 observed reflections with I 2σ（I） and 220 variable parameters. The crystal analysis shows that the hydrolysis product contains two rings, and a one- dimensional chain structure is formed via the intermolecular hydrogen bond O（1）–H（101）···N（2）.
文摘Analytical method for the residues of strobilurins azoxystrobin and pyraclostrobin in blueberries was developed. Fungicide residues were determined by solid-phase microextraction (SPME) cou-pled to gas chromatography with micro-electron capture detector. The effect of pH values and fiber coatings were studied. The SPME fiber coating selected was 100 μm PDMS. The method is selective with adequate precision and high accuracy and sensitivity. Recoveries ranged within the 100% - 106% range for azoxystrobin, and 96% - 106% range for pyraclostrobin;and detection and quantification limits were 2.0 and 6.0 μg/kg for azoxystrobin, and 26.0 and 86.0 μg/kg for py-raclostrobin, respectively. Statistical parameters indicated the occurrence of matrix effect;con-sequently calibration was performed on spiked samples. Degradation of azoxystrobin and pyra-clostrobin was studied in blueberry fields located in Concordia, Argentina, with fruits from Emerald and Jewel varieties. The degradation of these fungicides in both blueberry varieties studied followed a first order rate kinetics, and the half-life for azoxystrobin was 11.6 and 17.8 days for Emerald and Jewel cultivars;and for pyraclostrobin was 5.5 and 8.0 days, respectively.
基金sponsored by the National 973 Program of China (2006CB101907)the National 863 Program of China (2006AA10A211, 2008AA10Z414)the National Natural Science Foundation of China(30671048, 30671384)
文摘Azoxystrobin acts as an inhibitor of electron transport by binding to the Qo center of cytochrome b （cyt b）. Resistance to azoxystrobin was usually caused by the point mutation of cyt b gene or by the induction of alternative respiration. Oxygen consumption test for mycelia of Colletotrichum capsici showed that azoxystrobin inhibited mycelial respiration within 12 h; however, as time went on, the respiration of the mycelia recovered when the mycelia were treated with azoxystrobin and salicylhydroxamic acid （SHAM, a known inhibitor of alternative respiration）, and the oxygen consumption of the mycelia could not be inhibited. Meanwhile, cytochrome b （cyt b） gene expression increased with the recovery of mycelial respiration. The increased cyt b gene expression might play a role in the development of resistance to azoxystrobin in C. capsici.
基金supported by the National Key Research and Development Program of China(No.2017YFD0200503)the National Natural Science Foundation of China(Nos.21777144,21976161)the Changjiang Scholars and Innovative Re-search Team in University(No.IRT_17R97)。
文摘An effective broad-spectrum fungicide,azoxystrobin(AZ),has been widely detected in aquatic ecosystems,potentially affecting the growth of aquatic microorganisms.In the present study,the eukaryotic alga Monoraphidium sp.and the cyanobacterium Pseudanabaena sp.were exposed to AZ for 7 days.Our results showed that 0.2–0.5 mg/L concentrations of AZ slightly inhibited the growth of Monoraphidium sp.but stimulated Pseudanabaena sp.growth.Meanwhile,AZ treatment effectively increased the secretion of total organic carbon(TOC)in the culture media of the two species,and this phenomenon was also found in a freshwater microcosm experiment(containing the natural microbial community).We attempted to assess the effect of AZ on the function of aquatic microbial communities through metabolomic analysis and further explore the potential risks of this compound.The metabonomic profiles of the microcosm indicated that the most varied metabolites after AZ treatment were related to the citrate cycle(TCA),fatty acid biosynthesis and purine metabolism.We thereby inferred that the microbial community increased extracellular secretions by adjusting metabolic pathways,which might be a stress response to reduce AZ toxicity.Our results provide an important theoretical basis for further study of fungicide stress responses in aquatic microcosm microbial communities,as well as a good start for further explorations of AZ detoxification mechanisms,which will be valuable for the evaluation of AZ environmental risk.
文摘Background:Cultivation of red dragon fruit(Hylocereus polyrhizus)in Indonesian orchards is hampered by anthracnose and stem canker.A mixture of azoxystrobin 200 g/L+difenoconazole 125 g/L is recommended in supporting the obligated integrated pest management.For the consumer safety,dietary intake of the residues from fresh edible part should be assessed;therefore,information on correct dissipation pattern of the applied pesticide is required.Materials and Methods:Field residue trials in Indonesian highland(West Java)and coastal area(Special Region of Yogyakarta)were done at recommended dose was 0.151 kg ai/ha azoxystrobin and 0.094 kg ai/ha difenoconazole,three times at 10 days interval.Whole fruit samples were collected at 70%-100%ripeness at−1,0,1,3,7,10,and 14 days after last application,processed and determined its residue as soon as possible.Result and Discussion:Photoisomerization of azoxystrobin was observed at Day 0,especially in coastal area;however,it has been dissipated to below lowest validated level in the following day.At Day 0,3%-5%of the deposited azoxystrobin and difenoconazole penetrate into the flesh;however,most residues(95%-97%)were retained in peel,and dissipated in prolonged day.The dissipation pattern was non-linear.The dissipation data were better fit with bi-exponential double-first-order in parallel than single first-order kinetics model.The DT50 of both azoxystrobin and difenoconazole was 3 days.At harvest time,seventh day,only azoxystrobin residue was detected in flesh at 0.006 mg/kg;therefore,the long-term dietary risk was 0 per cent acceptable daily intake.Conclusion:Fresh red dragon fruit is safe to consume.
