High-performance liquid chromatography （HPLC） was employed to determine drug release rates based on emamectin benzoate concentrations in the medium. Release kinetics equations were used to fit the drug release behav...High-performance liquid chromatography （HPLC） was employed to determine drug release rates based on emamectin benzoate concentrations in the medium. Release kinetics equations were used to fit the drug release behavior. The effects of particle size and release medium pH on the release rate were also investigated. The indoor toxicity of emamectin benzoate-loaded polylactic acid microspheres on the diamondback moth larva （Plutella xylostella） was studied to explore drug sustained-release performance. In acidic and neutral media, the drug release behavior of the microspheres was in accord with the first-order kinetics equation. Increasing the spray dosage of emamectin benzoate-loaded polylactic acid microspheres initially resulted in an equivalent insecticidal efficacy with the conventional emamectin benzoate microemulsion. However, the drug persistence period was four-fold longer than that observed using the conventional formulation. The developed emamectin benzoate-loaded polylactic acid microspheres showed dramatic sustained-release performance. A treatment threshold of greater than 35 mg mL-1 was established for an efficient accumulated release concentration of emamectin benzoate-loaded microspheres.展开更多
In this study,we investigated the preventive effects of emamectin benzoate 9.7%SL,which was newly developed to reduce the injection volume and number of injection holes required to protect against pine wood nematode.N...In this study,we investigated the preventive effects of emamectin benzoate 9.7%SL,which was newly developed to reduce the injection volume and number of injection holes required to protect against pine wood nematode.None of the Pinus thunbergii trees injected with emamectin benzoate 9.7%SL at 0.3 mL/cm diameter at breast height(DBH)died within 2 years of inoculation with pine wood nematodes.Emamectin benzoate 9.7%SL injected at 0.6 mL/cm DBH resulted in no tree mortality for 3 years.Mean residue of emamectin benzoate 9.7%SL in pine twigs injected with 0.3 mL/cm DBH was 0.490μg/g at 1 year after injection and 0.303μg/g after 2 years.These residues values are greater than 0.031μg/g,previously determined IC95 value for emamectin benzoate against the pine wood nematode.Our field experiment and residue analysis showed that emamectin benzoate 9.7%SL could be a substitute agent for emamectin benzoate 2.15%EC,which is widely used to prevent pine wood nematode in the field and that injection volume and number of injection holes can be greatly educed using this new formulation,which will reduce injury to the cambium,interruption of water movement,and infection of inoculation wounds by wood-decay or blue stain fungi.展开更多
Based on determination for surface tension of organosilicone solution and its expansion on the solid surface, the biological activity of 5% emameetin ben- zoate WDG with organosilicone against beet armyworm was determ...Based on determination for surface tension of organosilicone solution and its expansion on the solid surface, the biological activity of 5% emameetin ben- zoate WDG with organosilicone against beet armyworm was determined by spraying method to study their synergistic activity. The results showed that organosilicone significandy reduced surface tension of aqueous solution, and the surface tension was reduced to 26raN/m as the concentration of organosilicone was 0.01%. The organosilicone significantly raised expansion of liquid drops on solid surface, and the expansion diameter of 10 μL 0.01% organosilicone was 34 ram. The indoor toxicity results indicated that when addition dosage of organosilieone was 1% -5%, synergistic activity of 5% emamectin benzoate WDG with organosilicone against beet armyworm was significant, and increase extent of synergistic activity slowed down as organosilieone dosage was higher than 5%. Field experiment showed that the control efficacies of 5% emamectin benzoate WDG ＋5% organosilicone 33 mg/ L against beet armyworm were 81.57% and 82.66% after spraying for 3 and 7 d respectively, which were significandy better than treatments of 5% emamectin benzoate WDG 33 rag/L, 24% metaflumizone SC 96 mg/L, 5% chlorantranilip- role SC 33 mg/L, 20% tlubendiamide WDG 40 mg/L and 15% indoxacarb EC 43 mg/L.展开更多
[Objective]The paper was to guide scientific and rational use of emamectin benzoate in ginger.[Method]A field experiment was conducted to determine residue and degradation dynamics and final residue of emamectin benzo...[Objective]The paper was to guide scientific and rational use of emamectin benzoate in ginger.[Method]A field experiment was conducted to determine residue and degradation dynamics and final residue of emamectin benzoate in ginger.The residue of emamectin benzoate in ginger was determined by high performance liquid chromatography-mass spectrometry(HPLC-MS/MS).[Result]The half-life of emamectin benzoate in ginger was 2.2-3.4 d.As 5%emamectin benzoate WDG was sprayed on ginger at 7.5 and 11.25 g·a.i/hm^2 for consecutive 1-2 times,the residues of emamectin benzoate in ginger harvested at 7,14 and 21 d post spraying were lower than the quantitative limit of the method(0.01 mg/kg),and were lower than the stipulation in Japan as well(0.1 mg/kg).[Conclusion]It is safe to use emamectin benzoate in ginger with the harvest interval of 7 d according to the recommended dose.展开更多
基金supported by the National Key Research and Development Program of China (2016YFD0200502, 2017YFD0200301)
文摘High-performance liquid chromatography （HPLC） was employed to determine drug release rates based on emamectin benzoate concentrations in the medium. Release kinetics equations were used to fit the drug release behavior. The effects of particle size and release medium pH on the release rate were also investigated. The indoor toxicity of emamectin benzoate-loaded polylactic acid microspheres on the diamondback moth larva （Plutella xylostella） was studied to explore drug sustained-release performance. In acidic and neutral media, the drug release behavior of the microspheres was in accord with the first-order kinetics equation. Increasing the spray dosage of emamectin benzoate-loaded polylactic acid microspheres initially resulted in an equivalent insecticidal efficacy with the conventional emamectin benzoate microemulsion. However, the drug persistence period was four-fold longer than that observed using the conventional formulation. The developed emamectin benzoate-loaded polylactic acid microspheres showed dramatic sustained-release performance. A treatment threshold of greater than 35 mg mL-1 was established for an efficient accumulated release concentration of emamectin benzoate-loaded microspheres.
基金This work was supported by a grant from Syngenta Korea to IK Park.
文摘In this study,we investigated the preventive effects of emamectin benzoate 9.7%SL,which was newly developed to reduce the injection volume and number of injection holes required to protect against pine wood nematode.None of the Pinus thunbergii trees injected with emamectin benzoate 9.7%SL at 0.3 mL/cm diameter at breast height(DBH)died within 2 years of inoculation with pine wood nematodes.Emamectin benzoate 9.7%SL injected at 0.6 mL/cm DBH resulted in no tree mortality for 3 years.Mean residue of emamectin benzoate 9.7%SL in pine twigs injected with 0.3 mL/cm DBH was 0.490μg/g at 1 year after injection and 0.303μg/g after 2 years.These residues values are greater than 0.031μg/g,previously determined IC95 value for emamectin benzoate against the pine wood nematode.Our field experiment and residue analysis showed that emamectin benzoate 9.7%SL could be a substitute agent for emamectin benzoate 2.15%EC,which is widely used to prevent pine wood nematode in the field and that injection volume and number of injection holes can be greatly educed using this new formulation,which will reduce injury to the cambium,interruption of water movement,and infection of inoculation wounds by wood-decay or blue stain fungi.
文摘Based on determination for surface tension of organosilicone solution and its expansion on the solid surface, the biological activity of 5% emameetin ben- zoate WDG with organosilicone against beet armyworm was determined by spraying method to study their synergistic activity. The results showed that organosilicone significandy reduced surface tension of aqueous solution, and the surface tension was reduced to 26raN/m as the concentration of organosilicone was 0.01%. The organosilicone significantly raised expansion of liquid drops on solid surface, and the expansion diameter of 10 μL 0.01% organosilicone was 34 ram. The indoor toxicity results indicated that when addition dosage of organosilieone was 1% -5%, synergistic activity of 5% emamectin benzoate WDG with organosilicone against beet armyworm was significant, and increase extent of synergistic activity slowed down as organosilieone dosage was higher than 5%. Field experiment showed that the control efficacies of 5% emamectin benzoate WDG ＋5% organosilicone 33 mg/ L against beet armyworm were 81.57% and 82.66% after spraying for 3 and 7 d respectively, which were significandy better than treatments of 5% emamectin benzoate WDG 33 rag/L, 24% metaflumizone SC 96 mg/L, 5% chlorantranilip- role SC 33 mg/L, 20% tlubendiamide WDG 40 mg/L and 15% indoxacarb EC 43 mg/L.
基金Supported by Agricultural Science and Technology Innovation Project of Shandong Academy of Agricultural Sciences(CXGC2018E19)
文摘[Objective]The paper was to guide scientific and rational use of emamectin benzoate in ginger.[Method]A field experiment was conducted to determine residue and degradation dynamics and final residue of emamectin benzoate in ginger.The residue of emamectin benzoate in ginger was determined by high performance liquid chromatography-mass spectrometry(HPLC-MS/MS).[Result]The half-life of emamectin benzoate in ginger was 2.2-3.4 d.As 5%emamectin benzoate WDG was sprayed on ginger at 7.5 and 11.25 g·a.i/hm^2 for consecutive 1-2 times,the residues of emamectin benzoate in ginger harvested at 7,14 and 21 d post spraying were lower than the quantitative limit of the method(0.01 mg/kg),and were lower than the stipulation in Japan as well(0.1 mg/kg).[Conclusion]It is safe to use emamectin benzoate in ginger with the harvest interval of 7 d according to the recommended dose.
