The efficacy of a synergistic mixture of cyhalothrin and abamectin in the control of Liriomyza sativae Blanchard

The co toxicity and co efficiency (CTC) of a mixture of abamectin as a biological pesticide and cyhalothrin as a chemical insecticide with low toxicity to mammals was determined with respect to Liriomyza sativae Blanchard. CTC of this mixture was equal to 161-232 in a range of marked synergism. According to the maximum of the proper proportion of cyhalothrin to abamectin, a 2% permeated WP synergistic formulation was manufactured. In the field trials the efficacy of this 2% WP against L. sativae larvae was excellent in both Shandong and Beijing districts. For example, at an application rate of 50?g/667m 2, corrected mortality in each zone after 3, 7 and 11 days was 85 26%-90 76% and 86 74%-94 02% respectively. At 25g/667m 2 the corresponding control effects were 75 28%-85 17% and 79 96%-88 68% respectively. This synergistic mixture was fast acting, had good residual performance and was relatively cost effective. Another advantage of using WP over EC pesticides is that a markedly less amount of chemicals are released into the environment, thereby decreasing pesticide pollution.