The aim of this work was to assess the effect of applying three different doses of fluxapyroxad on microbial activity, community structure and functional diversity as measured by respiration, microbial biomass C, phos...The aim of this work was to assess the effect of applying three different doses of fluxapyroxad on microbial activity, community structure and functional diversity as measured by respiration, microbial biomass C, phospholipid fatty acid （PLFA） and community-level physiological profiles （CLPPs）. Our results demonstrated that substrate-induced respiration （on day 15） and microbial biomass C （on days 7 and 15） were inhibited by fiuxapyroxad, but stimulation was observed thereafter. In contrast, fluxapyroxad addition increased the basal respiration and metabolic quotients （qCO2） and respiratory quotients （QR）. Analysis of the PLFA profiles revealed that the total and bacterial biomass （both Gram-positive bacteria （GP） and Gram-negative bacteria （GN）） were decreased within the initial 15 days, whereas those as well as the GN/GP ratio were increased at days 30 and 60. Fluxapyroxad input decreased the fungi biomass but increased the bacteria/fungi ratio at all incubation time. Moreover, high fluxapyroxad input （75 mg fluxapyroxad kg-1 soil dry weight） increased the microbial stress level. A principal component analysis （PCA） of the PLFAs revealed that fluxapyroxad treatment significantly shifted the microbial community structure, but all of the observed effects were transient. Biolog results showed that average well color development （AWCD） and functional diversity index （H′） were increased only on day 60. In addition, the dissipation of fluxa- pyroxad was slow in soil, and the degradation half-lives varied from 158 to 385 days depending on the concentration tested.展开更多
12%difenoconazole+fluxapyroxad SC(commercial name:Jiangong)was first released by BASF in China in 2016.It has been registered to control many diseases,including pear scab,apple Alternaria leaf spot,tomato early blight...12%difenoconazole+fluxapyroxad SC(commercial name:Jiangong)was first released by BASF in China in 2016.It has been registered to control many diseases,including pear scab,apple Alternaria leaf spot,tomato early blight,cucumber powdery mildew,etc.This study evaluated the bioactivity of Jiangong against Alternaria alternata and explored variations of phyllosphere microorganisms in both asymptomatic and tobacco brown spot leaves at different persistence periods(0,5,10,and 15 days post-fungicide application)using high-throughput sequencing technology.The results indicated that Jiangong effectively inhibited mycelial growth(average EC_(50) value of 0.51μg/mL),conidia germination(average EC_(50) value of 3.47μg/mL),and the carbon metabolism of A.alternata.Both asymptomatic and symptomatic leaves presented complex microbial communities.Higher fungal diversity was noted in asymptomatic leaves,while higher bacterial diversity was found in symptomatic leaves.After application,the diversity and abundance of microbial community structures in both types of leaves changed over time.Fungal microbiome communities showed greater sensitivity than bacterial groups,with the microbiome communities of asymptomatic leaves being more affected than those of symptomatic leaves.Fungal community diversity decreased for both symptomatic and asymptomatic leaves after 5 days of application,while the diversity of fungal community in symptomatic leaves showed an upward trend after 10 days of application.Meanwhile,bacterial community diversity increased in both symptomatic and asymptomatic leaves after 5 days of application but then declined in asymptomatic leaves after 15 days.The abundance of the dominant function group of phyllosphere bacteria(metabolism,genetic information processing,environmental information processing)was not affected by the application of Jiangong.However,the abundance of the dominant function group of phyllosphere fungi(animal pathogen-endophyte-wood saprotroph,endophyte-plant pathogen,plant pathogen-undefined saprotroph)was significantly affected by the application of Jiangong,and high variation was found in symptomatic leaves than that of asymptomatic leaves.The application of Jiangong-induced alterations in the community structure of the tobacco phyllosphere microbiome provides a basis for future tobacco brown spot control strategies based on phyllospheric microecology.展开更多
[Objectives]This study was conducted to investigate the joint toxicity of fungicides on aquatic ecosystems.[Methods]Using zebrafish as a model organism,an LC-MS/MS simultaneous detection method was established for flu...[Objectives]This study was conducted to investigate the joint toxicity of fungicides on aquatic ecosystems.[Methods]Using zebrafish as a model organism,an LC-MS/MS simultaneous detection method was established for fluxapyroxad and pyraclostrobin(with detection limits at ng/L level),and their acute toxicity,joint toxicity and toxic mechanisms were systematically evaluated.[Results]The toxicity of pyraclostrobin(96 h-LC 50=0.052 mg/L)to zebrafish was approximately 25.8 times higher than that of fluxapyroxad(96 h-LC 50=1.34 mg/L).Joint toxicity evaluation using the fixed-ratio ray design revealed that six of the seven mixture ratios exhibited additive effects(AI=0.62-1.47),while the 8:1 ratio showed antagonism(AI=2.14).The analysis of toxicity mechanisms indicated that both fungicides induced oxidative stress,lipid peroxidation,and cellular damage through inhibition of mitochondrial complex III and II,respectively,with pyraclostrobin inducing more pronounced hepatic MDA elevation(2.56-fold)and antioxidant enzyme inhibition.Ecological risk assessment demonstrated that fluxapyroxad posed moderate risk(RQ=0.16-0.90),while pyraclostrobin posed moderate to high risk(RQ=0.56-3.56),and crustaceans faced the highest risk.[Conclusions]This study elucidated the mechanism underlying toxicity differences due to distinct mitochondrial targets,providing a scientific basis for fungicide management.展开更多
本文采用高效液相色谱法,以乙腈加0.1%磷酸水溶液为流动相,使用Eclipse Plus C 18色谱柱和二极管阵列检测器,在210nm波长下对12%氟唑菌酰胺·氟环唑乳油进行分离和定量测定。结果表明,该分析方法条件下氟唑菌酰胺和氟环唑的线性相...本文采用高效液相色谱法,以乙腈加0.1%磷酸水溶液为流动相,使用Eclipse Plus C 18色谱柱和二极管阵列检测器,在210nm波长下对12%氟唑菌酰胺·氟环唑乳油进行分离和定量测定。结果表明,该分析方法条件下氟唑菌酰胺和氟环唑的线性相关系数分别为0.9997和0.9991,标准偏差分别为0.02和0.02,变异系数分别为0.31%和0.32%,平均回收率分别为100.18%和100.44%。展开更多
[目的]探讨42.4%唑醚·氟酰胺悬浮剂对番茄叶霉病的田间防治效果。[方法]以10%苯醚甲环唑水分散粒剂和70%甲基硫菌灵可湿性粉剂为对照药剂,采用小区试验研究42.4%唑醚·氟酰胺悬浮剂对番茄叶霉病的防治效果。[结果]42.4%唑醚...[目的]探讨42.4%唑醚·氟酰胺悬浮剂对番茄叶霉病的田间防治效果。[方法]以10%苯醚甲环唑水分散粒剂和70%甲基硫菌灵可湿性粉剂为对照药剂,采用小区试验研究42.4%唑醚·氟酰胺悬浮剂对番茄叶霉病的防治效果。[结果]42.4%唑醚·氟酰胺悬浮剂在剂量为150.0~225.0 g a.i./hm2时,对番茄叶霉病的防治效果为83.37%~91.63%,与10%苯醚甲环唑水分散粒剂120.0g a.i./hm^2对番茄叶霉病的防治效果无显著差异,但显著高于70%甲基硫菌灵可湿性粉剂562.5 g a.i./hm^2的防治效果。[结论]42.4%唑醚·氟酰胺悬浮剂可广泛用于番茄叶霉病的防治。展开更多
基金supported by the National Natural Science Foundation of China (31171879 and 31000863)the Special Fund for Agro-Scientific Research in the Public Interest, China (201203098)
文摘The aim of this work was to assess the effect of applying three different doses of fluxapyroxad on microbial activity, community structure and functional diversity as measured by respiration, microbial biomass C, phospholipid fatty acid （PLFA） and community-level physiological profiles （CLPPs）. Our results demonstrated that substrate-induced respiration （on day 15） and microbial biomass C （on days 7 and 15） were inhibited by fiuxapyroxad, but stimulation was observed thereafter. In contrast, fluxapyroxad addition increased the basal respiration and metabolic quotients （qCO2） and respiratory quotients （QR）. Analysis of the PLFA profiles revealed that the total and bacterial biomass （both Gram-positive bacteria （GP） and Gram-negative bacteria （GN）） were decreased within the initial 15 days, whereas those as well as the GN/GP ratio were increased at days 30 and 60. Fluxapyroxad input decreased the fungi biomass but increased the bacteria/fungi ratio at all incubation time. Moreover, high fluxapyroxad input （75 mg fluxapyroxad kg-1 soil dry weight） increased the microbial stress level. A principal component analysis （PCA） of the PLFAs revealed that fluxapyroxad treatment significantly shifted the microbial community structure, but all of the observed effects were transient. Biolog results showed that average well color development （AWCD） and functional diversity index （H′） were increased only on day 60. In addition, the dissipation of fluxa- pyroxad was slow in soil, and the degradation half-lives varied from 158 to 385 days depending on the concentration tested.
基金Supported by China National Tobacco Corporation[No.110202101048(LS-08)]Hundred’Level Innovative Talent Foundation of Guizhou Province(No.GCC[2022]028-1,GCC[2023]108)+2 种基金Guizhou Science Technology Foundation(No.ZK[2021]Key036)the National Natural Science Foundation of China(No.32160522)Guizhou Province Applied Technology Research and Development Funding Post-subsidy Project and Guizhou Tobacco Company(No.2020XM03,2020XM22,2024XM06).
文摘12%difenoconazole+fluxapyroxad SC(commercial name:Jiangong)was first released by BASF in China in 2016.It has been registered to control many diseases,including pear scab,apple Alternaria leaf spot,tomato early blight,cucumber powdery mildew,etc.This study evaluated the bioactivity of Jiangong against Alternaria alternata and explored variations of phyllosphere microorganisms in both asymptomatic and tobacco brown spot leaves at different persistence periods(0,5,10,and 15 days post-fungicide application)using high-throughput sequencing technology.The results indicated that Jiangong effectively inhibited mycelial growth(average EC_(50) value of 0.51μg/mL),conidia germination(average EC_(50) value of 3.47μg/mL),and the carbon metabolism of A.alternata.Both asymptomatic and symptomatic leaves presented complex microbial communities.Higher fungal diversity was noted in asymptomatic leaves,while higher bacterial diversity was found in symptomatic leaves.After application,the diversity and abundance of microbial community structures in both types of leaves changed over time.Fungal microbiome communities showed greater sensitivity than bacterial groups,with the microbiome communities of asymptomatic leaves being more affected than those of symptomatic leaves.Fungal community diversity decreased for both symptomatic and asymptomatic leaves after 5 days of application,while the diversity of fungal community in symptomatic leaves showed an upward trend after 10 days of application.Meanwhile,bacterial community diversity increased in both symptomatic and asymptomatic leaves after 5 days of application but then declined in asymptomatic leaves after 15 days.The abundance of the dominant function group of phyllosphere bacteria(metabolism,genetic information processing,environmental information processing)was not affected by the application of Jiangong.However,the abundance of the dominant function group of phyllosphere fungi(animal pathogen-endophyte-wood saprotroph,endophyte-plant pathogen,plant pathogen-undefined saprotroph)was significantly affected by the application of Jiangong,and high variation was found in symptomatic leaves than that of asymptomatic leaves.The application of Jiangong-induced alterations in the community structure of the tobacco phyllosphere microbiome provides a basis for future tobacco brown spot control strategies based on phyllospheric microecology.
基金Supported by New Project of Postgraduate Scientific Research Innovation in 2024(ZSCX2024Y21).
文摘[Objectives]This study was conducted to investigate the joint toxicity of fungicides on aquatic ecosystems.[Methods]Using zebrafish as a model organism,an LC-MS/MS simultaneous detection method was established for fluxapyroxad and pyraclostrobin(with detection limits at ng/L level),and their acute toxicity,joint toxicity and toxic mechanisms were systematically evaluated.[Results]The toxicity of pyraclostrobin(96 h-LC 50=0.052 mg/L)to zebrafish was approximately 25.8 times higher than that of fluxapyroxad(96 h-LC 50=1.34 mg/L).Joint toxicity evaluation using the fixed-ratio ray design revealed that six of the seven mixture ratios exhibited additive effects(AI=0.62-1.47),while the 8:1 ratio showed antagonism(AI=2.14).The analysis of toxicity mechanisms indicated that both fungicides induced oxidative stress,lipid peroxidation,and cellular damage through inhibition of mitochondrial complex III and II,respectively,with pyraclostrobin inducing more pronounced hepatic MDA elevation(2.56-fold)and antioxidant enzyme inhibition.Ecological risk assessment demonstrated that fluxapyroxad posed moderate risk(RQ=0.16-0.90),while pyraclostrobin posed moderate to high risk(RQ=0.56-3.56),and crustaceans faced the highest risk.[Conclusions]This study elucidated the mechanism underlying toxicity differences due to distinct mitochondrial targets,providing a scientific basis for fungicide management.
文摘本文采用高效液相色谱法,以乙腈加0.1%磷酸水溶液为流动相,使用Eclipse Plus C 18色谱柱和二极管阵列检测器,在210nm波长下对12%氟唑菌酰胺·氟环唑乳油进行分离和定量测定。结果表明,该分析方法条件下氟唑菌酰胺和氟环唑的线性相关系数分别为0.9997和0.9991,标准偏差分别为0.02和0.02,变异系数分别为0.31%和0.32%,平均回收率分别为100.18%和100.44%。
文摘[目的]探讨42.4%唑醚·氟酰胺悬浮剂对番茄叶霉病的田间防治效果。[方法]以10%苯醚甲环唑水分散粒剂和70%甲基硫菌灵可湿性粉剂为对照药剂,采用小区试验研究42.4%唑醚·氟酰胺悬浮剂对番茄叶霉病的防治效果。[结果]42.4%唑醚·氟酰胺悬浮剂在剂量为150.0~225.0 g a.i./hm2时,对番茄叶霉病的防治效果为83.37%~91.63%,与10%苯醚甲环唑水分散粒剂120.0g a.i./hm^2对番茄叶霉病的防治效果无显著差异,但显著高于70%甲基硫菌灵可湿性粉剂562.5 g a.i./hm^2的防治效果。[结论]42.4%唑醚·氟酰胺悬浮剂可广泛用于番茄叶霉病的防治。
