&lt;p&gt;The field experiment was conducted during kharif season of 2002 on cotton with an objective to evaluate bioefficacy of some newer synthetic insecticides against sucking pests of cotton viz.,Aphis gossypii (Glover), Amrasca biguttula (Ishida), Thrips tabaci (Hood) and Bemisia tabaci (Gennadius) and their safety to lady bird beetles. Laboratory experiment was also conducted to evaluate relative toxicity of synthetic insecticide treatment was judged on the basis of surviving population and seed cotton yield. In each insecticide treatment, two sprays were given at an interval of 20 days, initiating first spray at 30 days after sowing.&lt;br /&gt;
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In case of sucking pests, imidacloprid @22.25 g a.i./ha was highly effective against A.gossypii, A. biguttula and B. tabaci while thiamethoxam @ 25 g a.i/has was highly effective against T.tabaci.&lt;br /&gt;
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The maximum seed cotton yield (1564 kg/ha) was registered from the plots treated with imidacloprid @ 22.25 g a.i./ha. Thiamethoxam @ 25 g a.i./ha was the next best treatment which registered 1531 kg/ha yield of seed cotton.&lt;br /&gt;
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Acephate @ 350 g a.i./ha and imidacloprid @ 22.25 g a.i./ha were found to be highly toxic to coccinellids in the field as well as in the laboratory. NSKE was relatively safer to coccinellids in both conditions.&amp;nbsp;&lt;br /&gt;
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