Abstract:
Dissipation of acetamiprid and imidacloprid on Chinese mustard(Brassica chinensis)under different environmental and biological factors was investigated in stimulated condition. The half-life value of acetamiprid was 19.3 d,6.6 d and 5.2 d by 14℃、25℃ and 35℃,respectively.While that of imidacloprid was 8.7 d,3.8 d and 2.9 d in the same conditions. Although both of the dissipation speeds were accelrated with increasing temperature,their dissipation trends were not always uniform and the dissipation speed of imidacloprid was much faster than that of acetamiprid in the same condition. Under the light intensities of 500 lx,3 000 lx and 6 000 lx,the half-life value of acetamiprid was 19.1 d ,10.4 d and 6.6 d,and that of imidacloprid was 6.9 d,6.2 d and 3.7 d.Both of them were also depleted faster with increasing of light intensity,but the effect on acetamiprid depletions was more significantly than that on imidacloprid. By 25℃ and 6 000 lx light intensity,the half-life value of acetamiprid was 8.1 d and 6.6 d,that of imidacloprid was 3.5 d and 3.8 d with sterilization and nonsterilization of the leaves surface.Influence of microorganism to depletion speed on acetamprid wasalso more significant than that on imidacloprid.