The biological half-life and final residue levels of buprofezin and teflubenzuron were examined in peaches over a 14-day cultivation period. The residue levels of buprofezin and teflubenzuron were analyzed by chromato...The biological half-life and final residue levels of buprofezin and teflubenzuron were examined in peaches over a 14-day cultivation period. The residue levels of buprofezin and teflubenzuron were analyzed by chromatographic method with recovery ranging from 84.0% to 96.6%. The biological half-lives of buprofezin andteflubenzuron were 4.88 and 11.49 days at the standard dose, and 4.40 and 10.86 days at a triple dose, respectively. The initial concentration of buprofezin exceeded the maximum residue limit (MRL) set in Korea, but the concentration decreased to below the MRL within 6 days after application. The initial and persisting concentrations of teflubenzuron were all below the prescribed MRL. The final residue levels of buprofezin and teflubenzuron were 0.17 and 0.10?mg·kg﹣1 following a standard single dose, and 0.20 and 0.23 mg·kg﹣1 following a triple dose, respectively. The final re-sidue levels of buprofezin and teflubenzuron were also compared with the good agricultural practices standards of the United States and Italy.展开更多
The objective was to determine lethal concentrations and to evaluate the effects of sublethal doses of insecticides on Chrysodeixis includens under laboratory conditions. The standard population of C. includens was ke...The objective was to determine lethal concentrations and to evaluate the effects of sublethal doses of insecticides on Chrysodeixis includens under laboratory conditions. The standard population of C. includens was kept on artificial diet under controlled conditions (25°C ± 5°C, 60% ± 10 RU, 12:12 h). The active principles used were B. thuringiensis, Indoxacarb and Teflubenzuron. The CL25 and LC50 obtained from dose response curve (estimated from eight concentrations of each active principle) were diluted in water and applied to the back of third instar caterpillars and compared to the control (water). The insecticides used showed lethal and sublethal effects in C. includens. Bacillus thuringiensis was 6.21 and 2.79 times more toxic to soybean looper when compared to the products Indoxacarb and Teflubenzuron, respectively. Insecticides applied to the caterpillars reduced survival and affected the biomass gain with increased larvae and pupae longevity, with a significant reduction in fertility (40%) and fecundity (94.97%) in adults. In the present study it was observed that both survival and larval biomass gain have a direct effect on fecundity and fertility, respectively. Therefore the active ingredients Indoxacarb, Teflubenzuron and B. thuringiensis can be used in rotation as a tool in the C. includens.展开更多
文摘The biological half-life and final residue levels of buprofezin and teflubenzuron were examined in peaches over a 14-day cultivation period. The residue levels of buprofezin and teflubenzuron were analyzed by chromatographic method with recovery ranging from 84.0% to 96.6%. The biological half-lives of buprofezin andteflubenzuron were 4.88 and 11.49 days at the standard dose, and 4.40 and 10.86 days at a triple dose, respectively. The initial concentration of buprofezin exceeded the maximum residue limit (MRL) set in Korea, but the concentration decreased to below the MRL within 6 days after application. The initial and persisting concentrations of teflubenzuron were all below the prescribed MRL. The final residue levels of buprofezin and teflubenzuron were 0.17 and 0.10?mg·kg﹣1 following a standard single dose, and 0.20 and 0.23 mg·kg﹣1 following a triple dose, respectively. The final re-sidue levels of buprofezin and teflubenzuron were also compared with the good agricultural practices standards of the United States and Italy.
文摘The objective was to determine lethal concentrations and to evaluate the effects of sublethal doses of insecticides on Chrysodeixis includens under laboratory conditions. The standard population of C. includens was kept on artificial diet under controlled conditions (25°C ± 5°C, 60% ± 10 RU, 12:12 h). The active principles used were B. thuringiensis, Indoxacarb and Teflubenzuron. The CL25 and LC50 obtained from dose response curve (estimated from eight concentrations of each active principle) were diluted in water and applied to the back of third instar caterpillars and compared to the control (water). The insecticides used showed lethal and sublethal effects in C. includens. Bacillus thuringiensis was 6.21 and 2.79 times more toxic to soybean looper when compared to the products Indoxacarb and Teflubenzuron, respectively. Insecticides applied to the caterpillars reduced survival and affected the biomass gain with increased larvae and pupae longevity, with a significant reduction in fertility (40%) and fecundity (94.97%) in adults. In the present study it was observed that both survival and larval biomass gain have a direct effect on fecundity and fertility, respectively. Therefore the active ingredients Indoxacarb, Teflubenzuron and B. thuringiensis can be used in rotation as a tool in the C. includens.
