Biochar has been introduced as an acceptable soil amendment due to its environmental benefits such as sequestering soil contaminants. However, the aging process in biochar amended soil probably decreases the adsorptio...Biochar has been introduced as an acceptable soil amendment due to its environmental benefits such as sequestering soil contaminants. However, the aging process in biochar amended soil probably decreases the adsorption capacity of biochar through changing its physico-chemical properties. Adsorption, leaching and bioavailability of fomesafen to corn in a Chinese soil amended by rice hull biochar after 0, 30, 90 and 180 days were investigated. Results showed that the addition of 0.5%-2% fresh biochar significantly increases the adsorption of fomesafen 4-26 times compare to unamended soil due to higher SSA of biochar. Biochar amendment also decreases fomesafen concentration in soil pore water by 5%-23% resulting lower risk of the herbicide for cultivated plants. However, the aging process decreased the adsorption capacity ofbiochar since the adsorption coefficient values which was 1.9-12.4 in 0.5%-2% fresh biochar amended soil, declined to 1.36-4.16, 1.13-2.78 and 0.95-2.31 in 1, 3 and 6-month aged treatments, respectively. Consequently, higher desorption, leaching and bioavailable fraction of fomesafen belonged to 6-month aged treatment. Nevertheless, rice hull biochar was effective for sequestering fomesafen as the adsorption capacity of biochar amended soil after 6 months of aging was still 2.5-5 times hi^her compared to that of unamended soil.展开更多
Protoporphyrinogen oxidase (PPO) inhibitors are one of the few remaining postemergence herbicide options for controlling Palmer amaranth in soybean growing areas of Mississippi, USA. Most Palmer amaranth populations i...Protoporphyrinogen oxidase (PPO) inhibitors are one of the few remaining postemergence herbicide options for controlling Palmer amaranth in soybean growing areas of Mississippi, USA. Most Palmer amaranth populations in Mississippi are resistant to both glyphosate and acetolactate synthase inhibitors. Resistance to PPO inhibiting herbicides in Palmer amaranth has very recently been reported in Arkansas, Tennessee, and isolated pockets of Mississippi. A significant proportion of reports of PPO inhibitor failures in Mississippi are not considered to be resistance-related at this time. Therefore, the objective of this research was to evaluate factors affecting the efficacy of fomesafen on Palmer amaranth including: quality of spray carrier (water), formulations, adjuvant, rainfastness, and nozzle type. All water samples and formulation combinations provided >95% control of Palmer amaranth 3 WAT. Some combinations of water samples and formulations did not result in complete control of the treated plants, with one or two individuals surviving 3 WAT. Formulation 1 provided 99% control compared to 95% from formulation 2. Irrespective of combinations of herbicide, adjuvant and height, control of Palmer amaranth was ≥91%. Formulation 1 provided 94% control compared to 88% from formulation 2. The adjuvant x height interaction was significant, owing to a 10% reduction in control of larger plants (86%) compared to smaller plants (96%) in presence of COC. COC provided better control (93%) than NIS (88%). Simulated rainfall applied ≥60 min after herbicide application did not adversely affect efficacy on Palmer amaranth when formulation 1 was applied in combination with NIS, with control ranging from 94% to 100%. Formulation 1 with COC provided ≥93% control at all rainfall application times, except 30 min after herbicide treatment, which resulted in 79% control. Formulation 2 provided better control with COC (79% to 100%) than NIS (71% to 90%), in general, across the rainfall treatments applied at various times following herbicide application. All nozzle and weed height combinations resulted in 89% or better control of Palmer amaranth. In summary, water quality, formulation, adjuvant, rainfastness, or nozzle type did not affect the activity of fomesafen under optimal application conditions in the greenhouse.展开更多
New herbicide options are needed for postemergence (POST) broadleaf weed control in adzuki bean. A field study, of five experiments, was conducted over a three-year period (2014, 2015, 2016) in Ontario to evaluate the...New herbicide options are needed for postemergence (POST) broadleaf weed control in adzuki bean. A field study, of five experiments, was conducted over a three-year period (2014, 2015, 2016) in Ontario to evaluate the tolerance of adzuki bean to the POST application of acifluorfen (600 and 1200 g·ai·ha-1), fomesafen (240 and 480 g·ai·ha-1), bentazon (1080 and 2160 g·ai·ha-1), imazethapyr (100 and 200 g·ai·ha-1) and halosulfuron-methyl (75 and 150 g·ai·ha-1). Acifluorfen and fomesafen applied POST caused as much as 12% visible injury at the 1X rate and 20% visible injury at the 2X rate but had no adverse effect on adzuki bean population, shoot dry weight, height, maturity or yield. Bentazon caused as much as 23% visible injury at 1080 g·ai·ha-1 and 28% visible injury at 2160 g·ai·ha-1 but caused no adverse effect on adzuki bean population, shoot dry weight, height, maturity or yield at either rate, except at 2160 g·ai·ha-1 which reduced shoot dry weight 20% and height 12%. Imazethapyr caused as much as 22% visible injury at 100 g·ai·ha-1 and 34% visible injury at 200 g·ai·ha-1 but caused no adverse effect on adzuki bean population, shoot dry weight, height, maturity or yield at either rate except at 200 g·ai·ha-1 which delayed maturity slightly. Halosulfuron-methyl caused as much as 65% visible injury and reduced shoot dry weight, height and yield 64%, 41%, and 28%, respectively. This research concludes that acfluorfen, fomesafen, bentazon, imazethapyr and halosulfuron at the rates evaluated can cause the significant injury in adzuki bean.展开更多
Tank-mix adjuvant has the potential to improve the weed control efficacy of post-emergence herbicides. In order to study the synergistic effect of adjuvant, the effects of different rates of fomesafen alone or applied...Tank-mix adjuvant has the potential to improve the weed control efficacy of post-emergence herbicides. In order to study the synergistic effect of adjuvant, the effects of different rates of fomesafen alone or applied methylated soybean oil adjuvant（MSO） were sprayed on redroot pigweed, abutilon and black nightshade under greenhouse condition. The results showed that fomesafen had different performance on the three weeds, and MSO adjuvant could effectively increase the control. The nightshade control was lower than other two weeds with all the fomesafen doses from 131.25 to 506.25 ga.i. · hm-2 with or without adjuvant. The control of abutilon was between the black nightshade and the redroot pigweed, and had better control at 375 ga.i. · hm-2 with adjuvant or 506.25 ga.i. · hm-2 alone or with adjuvant respectively. The results indicated that mixing adjuvant with fomesafen improved the control on weeds, especially at the low rate. Black nightshade was more difficult to control. The redroot pigweed had the most susceptibility to fomesafen alone or with adjuvant.展开更多
High performance liquid chromatography(HPLC) was used to determine the degradation efficiency of bacteria 2 strain(B2 S) under different conditions, the optimum cultivation conditions for fomesafen degradation bacteri...High performance liquid chromatography(HPLC) was used to determine the degradation efficiency of bacteria 2 strain(B2 S) under different conditions, the optimum cultivation conditions for fomesafen degradation bacterium B2 S were as the followings: temperature 35℃; inoculation quantity 5%; p H 5.0; glucose content 0.5% and fomesafen concentration 10 mg · L-1. Under optimal conditions, B2 S degraded fomesafen within 72 h of fomesafen application, with a degradation rate of nearly 100%. High performance liquid chromatography-mass spectrometry(HPLC-MS) was used to analyze fomesafen degradation into microbial products. A more thorough understanding of microbial fomesafen degradation mechanisms was discussed. The pathway of fomesafen degradation by B2 S was also inferred herein.展开更多
【目的】明确黑龙江省嫩江市大豆田阔叶杂草反枝苋和藜对氟磺胺草醚的抗性水平及分布情况。【方法】在嫩江镇、海江镇、前进镇等10个乡(镇)采集反枝苋和藜的种子,通过整株生物测定法明确反枝苋和藜对氟磺胺草醚的抗性水平,并通过靶标基...【目的】明确黑龙江省嫩江市大豆田阔叶杂草反枝苋和藜对氟磺胺草醚的抗性水平及分布情况。【方法】在嫩江镇、海江镇、前进镇等10个乡(镇)采集反枝苋和藜的种子,通过整株生物测定法明确反枝苋和藜对氟磺胺草醚的抗性水平,并通过靶标基因PPX2序列扩增及比对等方法明确反枝苋对氟磺胺草醚产生抗性的原因。【结果】在氟磺胺草醚不同剂量处理后,采集的30个反枝苋种群的GR_(50)为8.70~814.77 g a.i./hm^(2),抗性指数(RI)为17.8~93.6。处于低水平抗性的反枝苋种群有14个,主要采自联兴乡、伊拉哈镇、塔溪乡;处于中等水平抗性的反枝苋种群有10个,主要采自双山镇、长福镇、科洛镇;处于高水平抗性的反枝苋种群有2个,主要采自海江镇。经靶标基因检测后发现26个抗性反枝苋种群均在PPX2基因上发生了Arg-128Gly突变;选择1个抗性反枝苋种群R利用P450和GST抑制剂处理后发现,其RI明显降低,说明存在非靶标抗性。在氟磺胺草醚不同剂量处理后,采集的26个藜种群的GR_(50)为51.54~497.10 g a.i./hm^(2),RI为1.0~9.5。处于低水平抗性的藜种群有10个,中等水平抗性的藜种群有6个,尚未发现对氟磺胺草醚产生高水平抗性的藜种群;对氟磺胺草醚产生抗性的藜种群主要来自临江乡、长福镇、科洛镇。【结论】当前黑龙江省嫩江市反枝苋和藜已经对氟磺胺草醚产生了不同水平的抗性,其中反枝苋对氟磺胺草醚同时存在靶标与非靶标抗性。展开更多
[目的]明确黑龙江省反枝苋种群对氟磺胺草醚的抗药性水平。[方法]采用整株生物测定法分别测定黑龙江省36个地区反枝苋种群对氟磺胺草醚的抗药性。[结果]牡丹江市东宁县绥阳镇爱国村的反枝苋种群的GR50最小,为72.9113 g a.i./hm^2,对氟...[目的]明确黑龙江省反枝苋种群对氟磺胺草醚的抗药性水平。[方法]采用整株生物测定法分别测定黑龙江省36个地区反枝苋种群对氟磺胺草醚的抗药性。[结果]牡丹江市东宁县绥阳镇爱国村的反枝苋种群的GR50最小,为72.9113 g a.i./hm^2,对氟磺胺草醚最敏感。佳木斯市汤原农场经济作物园区的反枝苋抗性指数为5.55,为低水平抗性。黑河市嫩江地区反枝苋的抗性指数为40.65～101.74,为高水平抗性。[结论]黑龙江省不同地区大豆田反枝苋对氟磺胺草醚的抗药性有明显的差异,黑河市嫩江地区的反枝苋对氟磺胺草醚产生了高水平抗性,其他地区处于敏感或低水平抗性阶段。展开更多
基金supported by the National High Technology R&D Program of China(Nos.2013AA102804,2012AA06A204)the National Natural Science Foundation of China(Nos.21177111,41271489)Zhejiang Provincial Natural Science Foundation(No.LZ13D010001)
文摘Biochar has been introduced as an acceptable soil amendment due to its environmental benefits such as sequestering soil contaminants. However, the aging process in biochar amended soil probably decreases the adsorption capacity of biochar through changing its physico-chemical properties. Adsorption, leaching and bioavailability of fomesafen to corn in a Chinese soil amended by rice hull biochar after 0, 30, 90 and 180 days were investigated. Results showed that the addition of 0.5%-2% fresh biochar significantly increases the adsorption of fomesafen 4-26 times compare to unamended soil due to higher SSA of biochar. Biochar amendment also decreases fomesafen concentration in soil pore water by 5%-23% resulting lower risk of the herbicide for cultivated plants. However, the aging process decreased the adsorption capacity ofbiochar since the adsorption coefficient values which was 1.9-12.4 in 0.5%-2% fresh biochar amended soil, declined to 1.36-4.16, 1.13-2.78 and 0.95-2.31 in 1, 3 and 6-month aged treatments, respectively. Consequently, higher desorption, leaching and bioavailable fraction of fomesafen belonged to 6-month aged treatment. Nevertheless, rice hull biochar was effective for sequestering fomesafen as the adsorption capacity of biochar amended soil after 6 months of aging was still 2.5-5 times hi^her compared to that of unamended soil.
文摘Protoporphyrinogen oxidase (PPO) inhibitors are one of the few remaining postemergence herbicide options for controlling Palmer amaranth in soybean growing areas of Mississippi, USA. Most Palmer amaranth populations in Mississippi are resistant to both glyphosate and acetolactate synthase inhibitors. Resistance to PPO inhibiting herbicides in Palmer amaranth has very recently been reported in Arkansas, Tennessee, and isolated pockets of Mississippi. A significant proportion of reports of PPO inhibitor failures in Mississippi are not considered to be resistance-related at this time. Therefore, the objective of this research was to evaluate factors affecting the efficacy of fomesafen on Palmer amaranth including: quality of spray carrier (water), formulations, adjuvant, rainfastness, and nozzle type. All water samples and formulation combinations provided >95% control of Palmer amaranth 3 WAT. Some combinations of water samples and formulations did not result in complete control of the treated plants, with one or two individuals surviving 3 WAT. Formulation 1 provided 99% control compared to 95% from formulation 2. Irrespective of combinations of herbicide, adjuvant and height, control of Palmer amaranth was ≥91%. Formulation 1 provided 94% control compared to 88% from formulation 2. The adjuvant x height interaction was significant, owing to a 10% reduction in control of larger plants (86%) compared to smaller plants (96%) in presence of COC. COC provided better control (93%) than NIS (88%). Simulated rainfall applied ≥60 min after herbicide application did not adversely affect efficacy on Palmer amaranth when formulation 1 was applied in combination with NIS, with control ranging from 94% to 100%. Formulation 1 with COC provided ≥93% control at all rainfall application times, except 30 min after herbicide treatment, which resulted in 79% control. Formulation 2 provided better control with COC (79% to 100%) than NIS (71% to 90%), in general, across the rainfall treatments applied at various times following herbicide application. All nozzle and weed height combinations resulted in 89% or better control of Palmer amaranth. In summary, water quality, formulation, adjuvant, rainfastness, or nozzle type did not affect the activity of fomesafen under optimal application conditions in the greenhouse.
文摘New herbicide options are needed for postemergence (POST) broadleaf weed control in adzuki bean. A field study, of five experiments, was conducted over a three-year period (2014, 2015, 2016) in Ontario to evaluate the tolerance of adzuki bean to the POST application of acifluorfen (600 and 1200 g·ai·ha-1), fomesafen (240 and 480 g·ai·ha-1), bentazon (1080 and 2160 g·ai·ha-1), imazethapyr (100 and 200 g·ai·ha-1) and halosulfuron-methyl (75 and 150 g·ai·ha-1). Acifluorfen and fomesafen applied POST caused as much as 12% visible injury at the 1X rate and 20% visible injury at the 2X rate but had no adverse effect on adzuki bean population, shoot dry weight, height, maturity or yield. Bentazon caused as much as 23% visible injury at 1080 g·ai·ha-1 and 28% visible injury at 2160 g·ai·ha-1 but caused no adverse effect on adzuki bean population, shoot dry weight, height, maturity or yield at either rate, except at 2160 g·ai·ha-1 which reduced shoot dry weight 20% and height 12%. Imazethapyr caused as much as 22% visible injury at 100 g·ai·ha-1 and 34% visible injury at 200 g·ai·ha-1 but caused no adverse effect on adzuki bean population, shoot dry weight, height, maturity or yield at either rate except at 200 g·ai·ha-1 which delayed maturity slightly. Halosulfuron-methyl caused as much as 65% visible injury and reduced shoot dry weight, height and yield 64%, 41%, and 28%, respectively. This research concludes that acfluorfen, fomesafen, bentazon, imazethapyr and halosulfuron at the rates evaluated can cause the significant injury in adzuki bean.
基金Supported by the Postdoctoral Grant of Heilongjiang Academy of Agricultural Sciences(LRB10-2446)the Doctoral Foundation of Northeast Agricultural University(2010RCB16)the Science and Technology Project of Heilongjiang Education Committee(12521034)
文摘Tank-mix adjuvant has the potential to improve the weed control efficacy of post-emergence herbicides. In order to study the synergistic effect of adjuvant, the effects of different rates of fomesafen alone or applied methylated soybean oil adjuvant（MSO） were sprayed on redroot pigweed, abutilon and black nightshade under greenhouse condition. The results showed that fomesafen had different performance on the three weeds, and MSO adjuvant could effectively increase the control. The nightshade control was lower than other two weeds with all the fomesafen doses from 131.25 to 506.25 ga.i. · hm-2 with or without adjuvant. The control of abutilon was between the black nightshade and the redroot pigweed, and had better control at 375 ga.i. · hm-2 with adjuvant or 506.25 ga.i. · hm-2 alone or with adjuvant respectively. The results indicated that mixing adjuvant with fomesafen improved the control on weeds, especially at the low rate. Black nightshade was more difficult to control. The redroot pigweed had the most susceptibility to fomesafen alone or with adjuvant.
基金Supported by Special Fund for Agro-scientific Research in the Public Interest(201303022)
文摘High performance liquid chromatography(HPLC) was used to determine the degradation efficiency of bacteria 2 strain(B2 S) under different conditions, the optimum cultivation conditions for fomesafen degradation bacterium B2 S were as the followings: temperature 35℃; inoculation quantity 5%; p H 5.0; glucose content 0.5% and fomesafen concentration 10 mg · L-1. Under optimal conditions, B2 S degraded fomesafen within 72 h of fomesafen application, with a degradation rate of nearly 100%. High performance liquid chromatography-mass spectrometry(HPLC-MS) was used to analyze fomesafen degradation into microbial products. A more thorough understanding of microbial fomesafen degradation mechanisms was discussed. The pathway of fomesafen degradation by B2 S was also inferred herein.
文摘【目的】明确黑龙江省嫩江市大豆田阔叶杂草反枝苋和藜对氟磺胺草醚的抗性水平及分布情况。【方法】在嫩江镇、海江镇、前进镇等10个乡(镇)采集反枝苋和藜的种子,通过整株生物测定法明确反枝苋和藜对氟磺胺草醚的抗性水平,并通过靶标基因PPX2序列扩增及比对等方法明确反枝苋对氟磺胺草醚产生抗性的原因。【结果】在氟磺胺草醚不同剂量处理后,采集的30个反枝苋种群的GR_(50)为8.70~814.77 g a.i./hm^(2),抗性指数(RI)为17.8~93.6。处于低水平抗性的反枝苋种群有14个,主要采自联兴乡、伊拉哈镇、塔溪乡;处于中等水平抗性的反枝苋种群有10个,主要采自双山镇、长福镇、科洛镇;处于高水平抗性的反枝苋种群有2个,主要采自海江镇。经靶标基因检测后发现26个抗性反枝苋种群均在PPX2基因上发生了Arg-128Gly突变;选择1个抗性反枝苋种群R利用P450和GST抑制剂处理后发现,其RI明显降低,说明存在非靶标抗性。在氟磺胺草醚不同剂量处理后,采集的26个藜种群的GR_(50)为51.54~497.10 g a.i./hm^(2),RI为1.0~9.5。处于低水平抗性的藜种群有10个,中等水平抗性的藜种群有6个,尚未发现对氟磺胺草醚产生高水平抗性的藜种群;对氟磺胺草醚产生抗性的藜种群主要来自临江乡、长福镇、科洛镇。【结论】当前黑龙江省嫩江市反枝苋和藜已经对氟磺胺草醚产生了不同水平的抗性,其中反枝苋对氟磺胺草醚同时存在靶标与非靶标抗性。
文摘采用温室盆栽法研究了6种不同结构的有机硅助剂对氟磺胺草醚防除阔叶杂草苘麻的增效作用及其增效机制。于苘麻4-5叶期,分别喷施添加有机硅助剂Agrowet 818、Agrowet 820、GY-S903、Sio-683、TD-600和TD-6408的氟磺胺草醚药液,测定药液对苘麻的抑制率及增效比;取苘麻6龄叶片,分别测定添加不同有机硅助剂后氟磺胺草醚药液的表面张力、在叶片上的扩展直径及最大持留量。结果表明：6种有机硅助剂对氟磺胺草醚的增效作用可达15.88%-23.04%;可以显著降低氟磺胺草醚药液的表面张力（由60.7 m N/m降至20-25 m N/m）,使药剂在叶片表面的最大持留量增加30%-70%,扩展直径由4.7 mm增至6.5-8.2 mm;其中,Agrowet 820增效作用最明显,可使表面张力降低65%,最大持留量增加69%,扩展直径增加74%,防效提高23.04%。
文摘采用分散固相萃取(QuEChERS)样品前处理方法,建立了超高效液相色谱-串联质谱(UPLC-MS/MS)快速检测大豆和土壤中氟磺胺草醚的残留分析方法.大豆和土壤样品采用乙腈(含0.5%甲酸)提取,N-丙基乙二胺(PSA)或石墨化碳黑(GCB)净化,UPLC-MS/MS外标法检测定量.在0.005—0.5 mg.kg-1添加范围内,氟磺胺草醚在土壤、大豆和大豆植株中的平均回收率在79.4%—109.0%之间,变异系数在3.6%—10.1%之间.在山东、河南、吉林进行了氟磺胺草醚在大豆植株和土壤中的降解动态研究,结果表明,试验点中氟磺胺草醚在土壤中的降解半衰期为8.5—23.7 d;在大豆植株中的降解半衰期为2.7—9.8 d.
文摘[目的]明确黑龙江省反枝苋种群对氟磺胺草醚的抗药性水平。[方法]采用整株生物测定法分别测定黑龙江省36个地区反枝苋种群对氟磺胺草醚的抗药性。[结果]牡丹江市东宁县绥阳镇爱国村的反枝苋种群的GR50最小,为72.9113 g a.i./hm^2,对氟磺胺草醚最敏感。佳木斯市汤原农场经济作物园区的反枝苋抗性指数为5.55,为低水平抗性。黑河市嫩江地区反枝苋的抗性指数为40.65～101.74,为高水平抗性。[结论]黑龙江省不同地区大豆田反枝苋对氟磺胺草醚的抗药性有明显的差异,黑河市嫩江地区的反枝苋对氟磺胺草醚产生了高水平抗性,其他地区处于敏感或低水平抗性阶段。
