Effects of the number of pesticide use on pesticide residues in oilseed rape plants and seeds.

Following the outbreak of rape pests,pesticide application rate and frequency increase,which raise the security issues of rapeseed oil.Two pesticides,avermectin and imidacloprid were previously selected to control major pests,diamondback moth,aphids,and cabbage worm,etc..The pesticide residues in the plant and grain and pesticide safety interval were further tested for the pesticides with different number of application to provide the basis for safe use of pesticides in green agricultural demonstration zone for rape.Under the same use frequency and dosage for the trial of two pesticides,the residue of abamectin was higher than imidacloprid.In oilseed rape plants and grains after application of imidacloprid,pesticide residues were not detected.After application of 2% abamectin,the pesticide residue in grain increased with the number of application,but did not exceed the maximum pesticide residue limit,0.05 mg/kg.The pesticide residue in plant also increased with the number of pesticide application and it was 46.15% more than pesticide residue in rapeseed.