[Objectives]The paper was to verify the field efficacy of 1%bifenthrin·thiamethoxam GR replacing organophosphorus GR against sweet potato weevil and its impact on the yield and quality of sweet potato.[Methods]A ...[Objectives]The paper was to verify the field efficacy of 1%bifenthrin·thiamethoxam GR replacing organophosphorus GR against sweet potato weevil and its impact on the yield and quality of sweet potato.[Methods]A total of 4 field trials were conducted in Guangdong Province,including 1%bifenthrin·thiamethoxam GR applied at the doses of 3,4 and 5 kg/667 m^(2),and 3%phoxim GR applied at the dose of 4 kg/667 m^(2).[Results]1%Bifenthrin·thiamethoxam GR applied at the dose of 5 kg/667 m^(2)had excellent control effects on sweet potato weevil,with an average control effect of 77.60%,which was significantly higher than that of 3%phoxim GR applied at the dose of 4 kg/667 m^(2)(48.52%).And the average yield increase rate of sweet potato treated with 1%bifenthrin·thiamethoxam GR reached 24.79%,significantly higher than 12.37%in the control group.[Conclusions]1%Bifenthrin·thiamethoxam GR should be evenly distributed on the ridge surface near sweet potato within 5-7 d after planting,and the recommended dosage is 5 kg/667 m^(2),which will have good control effect on sweet potato weevil and increase the yield of sweet potato.展开更多
Seed treatments with the neonicotinoid insecticides imidacloprid and thiamethoxam were evaluated to determine whether the chemicals at effective concentrations for aphid control would influence the germination and ear...Seed treatments with the neonicotinoid insecticides imidacloprid and thiamethoxam were evaluated to determine whether the chemicals at effective concentrations for aphid control would influence the germination and early growth of oilseed rape,Brassica napus.Treatment with imidacloprid or thiamethoxam did not affect the cumulative germination rate,but significantly inhibited establishment potential by suppressing root system development in the cotyledon stage.However,these alterations in seedling development in the thiamethoxam-treated seeds appeared not to be detrimental as leaves developed;in contrast,for the seedlings with imidacloprid as seed treatment agent,a significantly decreased shoot/root ratio was still evident at the late two-leaf stage.After two leaves developed,chlorophyll content per leaf in the thiamethoxam treatment was significantly higher than that of the control,while chlorophyll content per leaf in the imidacloprid treatment remained close to that in the control.Most other parameters,i.e.,height,leaf area,weight of stem,leaf or root,and other growth indexes,between the treatments and the control showed no significant difference.Additionally,it was found that storage time of the treated seeds had a significant effect on cumulative germination rate.Treatment 30 d before planting significantly reduced germination relative to that of the control.All of the plants treated with neonicotinoids were shown to have significant anti-aphid characteristics that persisted until the end of the trial.展开更多
[Objective] The paper was to provide scientific basis for popularization and application of 70% Thiamethoxam ZF. [Method] 70% Thiamethoxam ZF was selected and applied in the soil for controlling Ceratovacuna lanigera ...[Objective] The paper was to provide scientific basis for popularization and application of 70% Thiamethoxam ZF. [Method] 70% Thiamethoxam ZF was selected and applied in the soil for controlling Ceratovacuna lanigera Zehntner and Baliathrips serratus Kobus. [ Result ] 70% Thiamethoxam ZF had good con-rol effect against C. lanigera and B. serratus. The optimum dosage of 70% Thiamethoxam ZF was 450 g/hm^2 (effective ingredients 315 g). 70% Thiamethoxam ZF ( dosage per hm^2 ) mixed with the regular fertilizer ( dosage per hm^2 ) should be applied together in sugarcane planting and management from February to June. The control effects against C. lanigera and B. serratus were above 98.4% and 82.9% respectively. The actual yield and sugar content were increased by more than 34 290 kg/hm^2 and 6.8% respectively compared to blank control. [ Conclusion] 70% Thiamethoxam ZF was a new ideal pesticide with characteristics of sustained- release, long-lasting and low-toxic for controlling C. lanigera and B. serratus, and should be applied widely in the sugarcane planting area.展开更多
The linearity, stability, accuracy and inter-day precisions of the assay method were evaluated in water, soil and rhizomes and leaves of Hedychium coronarium of the Zingiberaceae family. Mato Grosso do Sul is a predom...The linearity, stability, accuracy and inter-day precisions of the assay method were evaluated in water, soil and rhizomes and leaves of Hedychium coronarium of the Zingiberaceae family. Mato Grosso do Sul is a predominantly agricultural state in Brazil and has many rivers and permanent and seasonal lakes, in which the Hedychium coronarium, an aquatic plant, is found the swampy environments. The prepared samples were analyzed quantitatively by High Performance Liquid Chromatography with PDA and UV detection for the presence of thiamethoxam. The thiamethoxam was recovered from these samples at rates ranging from 81.16% - 99.93%. The coefficient of variation in the quantitative analysis of the thiamethoxam was under 5%. The linearity of the method was determined by linear regression. The analysis of the samples spiked with known amounts of analyte demonstrated that the response was proportional to the concentrations of the samples with determination coefficients of r2 = 0.9992 (water and soil) and r2 = 0.9990 (leaves and rhizomes) for the linear range of the analytical calibration curves of the samples. The detection limit was 0.36 μg.L-1 and quantification limit was 1.2 μg.L-1 for thiamethoxam. The method was considered sensitive for quantification of the thiamethoxam in water, soil and rhizomes and leaves of Hedychium coronarium.展开更多
Nano-delivery systems have been applied to deliver various synthetic/botanical pesticides to increase the efficiency of pesticide use and reduce the volumes of pesticides applied.Previous studies have supported the hy...Nano-delivery systems have been applied to deliver various synthetic/botanical pesticides to increase the efficiency of pesticide use and reduce the volumes of pesticides applied.Previous studies have supported the hypothesis that the nanocarriers can help expand the insecticidal target of pesticides to include non-target pests.However,the potential mechanism underlying this interesting phenomenon remains unclear.Herein,a widely applied star polycation(SPc)nanocarrier was synthesized to construct a thiamethoxam(TMX)nano-delivery system.The SPc-based delivery system could promote the translocation of exogenous substances across the membrane of Sf9 cells,increase the cytotoxicity of TMX against Sf9 cells by nearly 20%,and expand the insecticidal target of TMX to include Spodoptera frugiperda(the fall armyworm),with a 27.5%mortality increase at a concentration of 0.25 mg/mL.Moreover,the RNA-seq analysis demonstrated that the SPc could upregulate various transport-related genes,such as Rab,SORT1,CYTH,and PIKfive,for the enhanced cellular uptake of TMX.Furthermore,enhanced cell death in larvae treated with the TMX-SPc complex was observed through changes in the expression levels of death-related genes,such as Casp7,BIRC5,MSK1,and PGAM5.The SPc-based nano-delivery system improved the cellular uptake of TMX and expanded its insecticidal target by adjusting the expression levels of death-related genes.The current study mainly identified the transport and cell death genes related to nanocarrier-based insecticidal target expansion,which is beneficial for understanding the bioactivity enhancement of the nano-delivery system.展开更多
文摘[Objectives]The paper was to verify the field efficacy of 1%bifenthrin·thiamethoxam GR replacing organophosphorus GR against sweet potato weevil and its impact on the yield and quality of sweet potato.[Methods]A total of 4 field trials were conducted in Guangdong Province,including 1%bifenthrin·thiamethoxam GR applied at the doses of 3,4 and 5 kg/667 m^(2),and 3%phoxim GR applied at the dose of 4 kg/667 m^(2).[Results]1%Bifenthrin·thiamethoxam GR applied at the dose of 5 kg/667 m^(2)had excellent control effects on sweet potato weevil,with an average control effect of 77.60%,which was significantly higher than that of 3%phoxim GR applied at the dose of 4 kg/667 m^(2)(48.52%).And the average yield increase rate of sweet potato treated with 1%bifenthrin·thiamethoxam GR reached 24.79%,significantly higher than 12.37%in the control group.[Conclusions]1%Bifenthrin·thiamethoxam GR should be evenly distributed on the ridge surface near sweet potato within 5-7 d after planting,and the recommended dosage is 5 kg/667 m^(2),which will have good control effect on sweet potato weevil and increase the yield of sweet potato.
基金supported by the National Special Fund for Agro-Scientific Research of Public Interests of China(201303030)the Anhui Provincial Natural Science Foundation,China(1408085MKL65)
文摘Seed treatments with the neonicotinoid insecticides imidacloprid and thiamethoxam were evaluated to determine whether the chemicals at effective concentrations for aphid control would influence the germination and early growth of oilseed rape,Brassica napus.Treatment with imidacloprid or thiamethoxam did not affect the cumulative germination rate,but significantly inhibited establishment potential by suppressing root system development in the cotyledon stage.However,these alterations in seedling development in the thiamethoxam-treated seeds appeared not to be detrimental as leaves developed;in contrast,for the seedlings with imidacloprid as seed treatment agent,a significantly decreased shoot/root ratio was still evident at the late two-leaf stage.After two leaves developed,chlorophyll content per leaf in the thiamethoxam treatment was significantly higher than that of the control,while chlorophyll content per leaf in the imidacloprid treatment remained close to that in the control.Most other parameters,i.e.,height,leaf area,weight of stem,leaf or root,and other growth indexes,between the treatments and the control showed no significant difference.Additionally,it was found that storage time of the treated seeds had a significant effect on cumulative germination rate.Treatment 30 d before planting significantly reduced germination relative to that of the control.All of the plants treated with neonicotinoids were shown to have significant anti-aphid characteristics that persisted until the end of the trial.
基金Supported by Special Fund for China Agricultural Industry Research System(CARS-20-2-2)Special Fund for Agricultural Industry Research System of Yunnan Province(YNGZTX-4-92)
文摘[Objective] The paper was to provide scientific basis for popularization and application of 70% Thiamethoxam ZF. [Method] 70% Thiamethoxam ZF was selected and applied in the soil for controlling Ceratovacuna lanigera Zehntner and Baliathrips serratus Kobus. [ Result ] 70% Thiamethoxam ZF had good con-rol effect against C. lanigera and B. serratus. The optimum dosage of 70% Thiamethoxam ZF was 450 g/hm^2 (effective ingredients 315 g). 70% Thiamethoxam ZF ( dosage per hm^2 ) mixed with the regular fertilizer ( dosage per hm^2 ) should be applied together in sugarcane planting and management from February to June. The control effects against C. lanigera and B. serratus were above 98.4% and 82.9% respectively. The actual yield and sugar content were increased by more than 34 290 kg/hm^2 and 6.8% respectively compared to blank control. [ Conclusion] 70% Thiamethoxam ZF was a new ideal pesticide with characteristics of sustained- release, long-lasting and low-toxic for controlling C. lanigera and B. serratus, and should be applied widely in the sugarcane planting area.
文摘The linearity, stability, accuracy and inter-day precisions of the assay method were evaluated in water, soil and rhizomes and leaves of Hedychium coronarium of the Zingiberaceae family. Mato Grosso do Sul is a predominantly agricultural state in Brazil and has many rivers and permanent and seasonal lakes, in which the Hedychium coronarium, an aquatic plant, is found the swampy environments. The prepared samples were analyzed quantitatively by High Performance Liquid Chromatography with PDA and UV detection for the presence of thiamethoxam. The thiamethoxam was recovered from these samples at rates ranging from 81.16% - 99.93%. The coefficient of variation in the quantitative analysis of the thiamethoxam was under 5%. The linearity of the method was determined by linear regression. The analysis of the samples spiked with known amounts of analyte demonstrated that the response was proportional to the concentrations of the samples with determination coefficients of r2 = 0.9992 (water and soil) and r2 = 0.9990 (leaves and rhizomes) for the linear range of the analytical calibration curves of the samples. The detection limit was 0.36 μg.L-1 and quantification limit was 1.2 μg.L-1 for thiamethoxam. The method was considered sensitive for quantification of the thiamethoxam in water, soil and rhizomes and leaves of Hedychium coronarium.
基金the National Key R&D Program of China(2021YFC2600404)the National Science Foundation of China(32072497).
文摘Nano-delivery systems have been applied to deliver various synthetic/botanical pesticides to increase the efficiency of pesticide use and reduce the volumes of pesticides applied.Previous studies have supported the hypothesis that the nanocarriers can help expand the insecticidal target of pesticides to include non-target pests.However,the potential mechanism underlying this interesting phenomenon remains unclear.Herein,a widely applied star polycation(SPc)nanocarrier was synthesized to construct a thiamethoxam(TMX)nano-delivery system.The SPc-based delivery system could promote the translocation of exogenous substances across the membrane of Sf9 cells,increase the cytotoxicity of TMX against Sf9 cells by nearly 20%,and expand the insecticidal target of TMX to include Spodoptera frugiperda(the fall armyworm),with a 27.5%mortality increase at a concentration of 0.25 mg/mL.Moreover,the RNA-seq analysis demonstrated that the SPc could upregulate various transport-related genes,such as Rab,SORT1,CYTH,and PIKfive,for the enhanced cellular uptake of TMX.Furthermore,enhanced cell death in larvae treated with the TMX-SPc complex was observed through changes in the expression levels of death-related genes,such as Casp7,BIRC5,MSK1,and PGAM5.The SPc-based nano-delivery system improved the cellular uptake of TMX and expanded its insecticidal target by adjusting the expression levels of death-related genes.The current study mainly identified the transport and cell death genes related to nanocarrier-based insecticidal target expansion,which is beneficial for understanding the bioactivity enhancement of the nano-delivery system.