residual effect of lambdacyhalothrin (icon 10% wp) on different surfaces in south of iran

an investigation was made to study the residual activity and air-borne effect of lambdacyhalothrin (icon 10 wp) at 30, 40 and 50 a.i. mg/rn2 against an.stephensi in hut scale trials on different surfaces in mamasani, and rudan, south of iran. bio-assay contact mortality test with icon at 30 a.i. mgl/m2 on plaster, cement and wood surfaces decreased from 100% to 51.4%, 53% and 63.8% after 84, 80 and 107 days of hut spraying, respectively. at 40 a.i mg/m2 icon showed longer residual activity than the 30 mg/rn2, i.e. the mortality rate deceased from 100% to 50.7% for plaster, to 52.5% for cement and to 53.5% for wood surfaces, after 105, 105 and 124 days of hut spraying, respectively. icon at 50 a.i. mg/m2 showed longer residual activity than the former dosages, i.e. the mortality dropped from 100% to 62.1% for plaster, to 50.7% for cement and to 90.4% for wooden surfaces, after 124 days of hut spraying, respectively. the result of air home tests showed that icon has negligible or slight killing effect on an.stephensi, i.e. at 30. 40 and 50 a.i. mg/m2, the mortality rates dropped from 100% to about 60% after 10, 15 and 25 days of hut spraying, respectively. based on the results of this study lambdacyhalothrin at 50/m2 had a residual activity for more than 4 months on different surface. it could be concluded that, lambdacyhalothrin at 50 mg/m2 might be a candidate dosage for continuation of study in village scale vial in south of iran.