[Objectives]This study was conducted to investigate the compounding of three herbicides:clopyralid,picloram and benazolin,so as to improve the effectiveness of herbicides.[Methods]With Lapsana apogonoides Maxim.as the...[Objectives]This study was conducted to investigate the compounding of three herbicides:clopyralid,picloram and benazolin,so as to improve the effectiveness of herbicides.[Methods]With Lapsana apogonoides Maxim.as the target and clopyralid,picloram and benazolin as the test agents,seven gradient concentrations were set up to determine the joint toxicity of the three agents.[Results]When the compounding ratio of picloram,clopyralid and benazolin was 2∶1∶6,the maximum co-toxicity coefficient was 290.0.[Conclusions]The compounding of picloram,clopyralid and benazolin has a significant synergistic effect on L.apogonoides,which reduces production costs and environmental pressure,providing technical support for the effective control of broad-leaved weeds such as L.apogonoides.展开更多
The contaminant of herbicide clopyralid(3,6-dichloro-2-pyridine-carboxylic acid,CLP)poses a potential threat to the ecological system.However,there is a general lack of research devoted to the perturbation of CLP to t...The contaminant of herbicide clopyralid(3,6-dichloro-2-pyridine-carboxylic acid,CLP)poses a potential threat to the ecological system.However,there is a general lack of research devoted to the perturbation of CLP to the bio-denitrification process,and its biological response mechanism remains unclear.Herein,long-term exposure to CLP was systematically investigated to explore its influences on denitrification performance and dynamic microbial responses.Results showed that low-concentration of CLP(<15 mg/L)caused severe nitrite accumulation initially,while higher concentrations(35e60 mg/L)of CLP had no further effect after long-term acclimation.The mechanistic study demonstrated that CLP reduced nitrite reductase(NIR)activity and inhibited metabolic activity(carbon metabolism and nitrogen metabolism)by causing oxidative stress and membrane damage,resulting in nitrite accumulation.However,after more than 80 days of acclimation,almost no nitrite accumulation was found at 60 mg/L CLP.It was proposed that the secretion of extracellular polymeric substances(EPS)increased from 75.03 mg/g VSS at 15 mg/L CLP to 109.97 mg/g VSS at 60 mg/L CLP,which strengthened the protection of microbial cells and improved NIR activity and metabolic activities.Additionally,the biodiversity and richness of the microbial community experienced a U-shaped process.The relative abundance of denitrification-and carbon metabolism-associated microorganisms decreased initially and then recovered with the enrichment of microorganisms related to the secretion of EPS and N-acyl-homoserine lactones(AHLs).These microorganisms protected microbe from toxic substances and regulated their interactions among interand intra-species.This study revealed the biological response mechanism of denitrification after successive exposure to CLP and provided proper guidance for analyzing and treating herbicide-containing wastewater.展开更多
为筛选防除青海省农田恶性杂草的高效除草剂,采用茎叶喷雾法室内测定了30%氨氯·二氯·氯氨吡啶酸可溶液剂(SL)对密花香薷、藜、苣荬菜、地肤、野芥菜的除草活性。结果表明:30%氨氯·二氯·氯氨吡啶酸SL施药后7 d对供试...为筛选防除青海省农田恶性杂草的高效除草剂,采用茎叶喷雾法室内测定了30%氨氯·二氯·氯氨吡啶酸可溶液剂(SL)对密花香薷、藜、苣荬菜、地肤、野芥菜的除草活性。结果表明:30%氨氯·二氯·氯氨吡啶酸SL施药后7 d对供试的5种杂草株高均有不同程度的抑制,施药后14 d对杂草的抑制作用比施药后7 d明显增强。施药后21 d 30%氨氯·二氯·氯氨吡啶酸SL 45.0、67.5、90.0、112.5、135.0 g a.i/hm2处理对密花香薷的鲜重防效分别为71.85%、75.87%、82.80%、89.81%、90.42%;对藜的鲜重防效分别为87.25%、100.00%、100.00%、100.00%、100.00%;对苣荬菜的鲜重防效分别为71.95%、72.14%、80.39%、85.84%、89.26%;对地肤的鲜重防效分别为68.48%、75.30%、78.33%、80.00%、85.76%;对野芥菜的鲜重防效分别为48.76%、66.56%、72.47%、78.22%、84.71%。30%氨氯·二氯·氯氨吡啶酸SL对密花香薷、藜、苣荬菜、地肤、野芥菜的ED90分别为130.27、33.36、161.38、241.20、185.49 g a.i/hm2。说明30%氨氯·二氯·氯氨吡啶酸SL能够扩大杀草谱,有效防除青海省农田中的阔叶杂草,本研究结果可为青海省农田阔叶杂草防除提供参考数据。展开更多
建立了搅拌棒吸附萃取-液相色谱-串联质谱(SBSE-LC-MS/MS)法测定农业废水中二氯吡啶酸残留量的分析方法。样品经搅拌棒吸附萃取,以BEH C 18柱为分析柱,以乙腈和0.1%甲酸溶液为流动相进行梯度洗脱,采用质谱测定。结果表明:二氯吡啶酸质...建立了搅拌棒吸附萃取-液相色谱-串联质谱(SBSE-LC-MS/MS)法测定农业废水中二氯吡啶酸残留量的分析方法。样品经搅拌棒吸附萃取,以BEH C 18柱为分析柱,以乙腈和0.1%甲酸溶液为流动相进行梯度洗脱,采用质谱测定。结果表明:二氯吡啶酸质量浓度在1.0~50.0 ng/mL范围内与其质谱响应值呈线性关系,相关系数(r)为0.9998;方法检出限为0.3μg/L,方法定量限为1.0μg/L;加标回收率范围87.8%~97.8%;相对标准偏差(RSD,n=6)为0.9%~4.7%。本方法操作简便、试剂消耗少、准确度高、检出限低,适用于农业废水中二氯吡啶酸含量监测。展开更多
基金Double First-class Applied Characteristic Disciplines in Hunan Province(Plant protection)Excellent Agriculture and Forestry Talent Cultivation Project of Hunan Institute of Humanities,Science and TechnologyNew Agricultural Science Research and Reform Practice Project in Hunan Province(XJT[2020]94).
文摘[Objectives]This study was conducted to investigate the compounding of three herbicides:clopyralid,picloram and benazolin,so as to improve the effectiveness of herbicides.[Methods]With Lapsana apogonoides Maxim.as the target and clopyralid,picloram and benazolin as the test agents,seven gradient concentrations were set up to determine the joint toxicity of the three agents.[Results]When the compounding ratio of picloram,clopyralid and benazolin was 2∶1∶6,the maximum co-toxicity coefficient was 290.0.[Conclusions]The compounding of picloram,clopyralid and benazolin has a significant synergistic effect on L.apogonoides,which reduces production costs and environmental pressure,providing technical support for the effective control of broad-leaved weeds such as L.apogonoides.
基金the National Natural Science Foundation of China(Grant No.52000134)China Postdoctoral Science Foundation(No.2020M680894)+2 种基金Tianjin Science and Technology Program(No.21YDTPJC00700)Natural Science Foundation of Tianjin Science and Technology Correspondent Project(No.19JCQNJC07800)Tianjin Synthetic Biotechnology Innovation Capacity Improvement Project(No.TSBICIP-CXRC-007).
文摘The contaminant of herbicide clopyralid(3,6-dichloro-2-pyridine-carboxylic acid,CLP)poses a potential threat to the ecological system.However,there is a general lack of research devoted to the perturbation of CLP to the bio-denitrification process,and its biological response mechanism remains unclear.Herein,long-term exposure to CLP was systematically investigated to explore its influences on denitrification performance and dynamic microbial responses.Results showed that low-concentration of CLP(<15 mg/L)caused severe nitrite accumulation initially,while higher concentrations(35e60 mg/L)of CLP had no further effect after long-term acclimation.The mechanistic study demonstrated that CLP reduced nitrite reductase(NIR)activity and inhibited metabolic activity(carbon metabolism and nitrogen metabolism)by causing oxidative stress and membrane damage,resulting in nitrite accumulation.However,after more than 80 days of acclimation,almost no nitrite accumulation was found at 60 mg/L CLP.It was proposed that the secretion of extracellular polymeric substances(EPS)increased from 75.03 mg/g VSS at 15 mg/L CLP to 109.97 mg/g VSS at 60 mg/L CLP,which strengthened the protection of microbial cells and improved NIR activity and metabolic activities.Additionally,the biodiversity and richness of the microbial community experienced a U-shaped process.The relative abundance of denitrification-and carbon metabolism-associated microorganisms decreased initially and then recovered with the enrichment of microorganisms related to the secretion of EPS and N-acyl-homoserine lactones(AHLs).These microorganisms protected microbe from toxic substances and regulated their interactions among interand intra-species.This study revealed the biological response mechanism of denitrification after successive exposure to CLP and provided proper guidance for analyzing and treating herbicide-containing wastewater.
文摘为筛选防除青海省农田恶性杂草的高效除草剂,采用茎叶喷雾法室内测定了30%氨氯·二氯·氯氨吡啶酸可溶液剂(SL)对密花香薷、藜、苣荬菜、地肤、野芥菜的除草活性。结果表明:30%氨氯·二氯·氯氨吡啶酸SL施药后7 d对供试的5种杂草株高均有不同程度的抑制,施药后14 d对杂草的抑制作用比施药后7 d明显增强。施药后21 d 30%氨氯·二氯·氯氨吡啶酸SL 45.0、67.5、90.0、112.5、135.0 g a.i/hm2处理对密花香薷的鲜重防效分别为71.85%、75.87%、82.80%、89.81%、90.42%;对藜的鲜重防效分别为87.25%、100.00%、100.00%、100.00%、100.00%;对苣荬菜的鲜重防效分别为71.95%、72.14%、80.39%、85.84%、89.26%;对地肤的鲜重防效分别为68.48%、75.30%、78.33%、80.00%、85.76%;对野芥菜的鲜重防效分别为48.76%、66.56%、72.47%、78.22%、84.71%。30%氨氯·二氯·氯氨吡啶酸SL对密花香薷、藜、苣荬菜、地肤、野芥菜的ED90分别为130.27、33.36、161.38、241.20、185.49 g a.i/hm2。说明30%氨氯·二氯·氯氨吡啶酸SL能够扩大杀草谱,有效防除青海省农田中的阔叶杂草,本研究结果可为青海省农田阔叶杂草防除提供参考数据。
文摘建立了搅拌棒吸附萃取-液相色谱-串联质谱(SBSE-LC-MS/MS)法测定农业废水中二氯吡啶酸残留量的分析方法。样品经搅拌棒吸附萃取,以BEH C 18柱为分析柱,以乙腈和0.1%甲酸溶液为流动相进行梯度洗脱,采用质谱测定。结果表明:二氯吡啶酸质量浓度在1.0~50.0 ng/mL范围内与其质谱响应值呈线性关系,相关系数(r)为0.9998;方法检出限为0.3μg/L,方法定量限为1.0μg/L;加标回收率范围87.8%~97.8%;相对标准偏差(RSD,n=6)为0.9%~4.7%。本方法操作简便、试剂消耗少、准确度高、检出限低,适用于农业废水中二氯吡啶酸含量监测。
