Efficiency of Insecticides Imidacloprid, Chlorpyrifos, Cypermethrin and Palizin in Control of Planthopper, Orosanga Japonicus Melichar on Ornamental Plant, Euonymus japonicus Thunb.

The planthopper, Orosanga japonicus Melichar (Hem.: Ricaniidae) with feeding on plant sap, excreting honeydew and providing the growth of black sooty mould affects the beauty of the spindle plant, Euonymus japonicus. In this research, efficiency of three chemical insecticides, imidacloprid (0.5 ml/L), chlorpyrifos (2 ml/L), cypermethrin (0.5 ml/L) against O. japonicus was compared with a botanical insecticide, palizin® (2.5 ml/L). Each treatment consisted of three replications and 3 m in length of Euonymus plant that number of live leafhoppers on it was counted one day before spraying up to 5 days after spraying. The efficiency of insecticides was calculated according to Henderson and Tilton’s formula. The most effective insecticide in control of O. japonicus was cypermethrin (100% efficiency). After cypermethrin, imidacloprid caused remarkable efficiency (97-100%). The highest efficiency of palizin® and chlorpyrifos was obtained on the first day (93.8%) and on the second day (80.3%) after treatment, respectively. So, palizin® can be effective in control of O. japonicus because of low risk for the environment and may be used instead of hazardous chemical insecticides in control of O. japonicus.