Efficacy of Carbaryl, Fipronil and Cypermethrin Against Flat-back Millipede, <I>Antheromorpha uncinata</I> Jeekel

Abstract

Over the last decades, some millipede outbreak is periodically occurred resulting in making trouble to people occupying in the areas. Use of chemicals for their control is an alternative choice to reduce this problem. The aim of current research was to study the effects of carbaryl, fipronil and cypermethrin on Antheromorpha uncinata Jeekel, 1968, in San Klang subdistrict, Phan district, Chiang Rai province. Millipede samples were treated with various insecticide concentration by direct spray. The percentage mortality was evaluated after 1, 12, 24 and 48 hours of exposure. Fipronil showed the highest LC₅₀ value as 97.69 and 23.81 ppm at 1 and 24 hours, respectively. Cypermethrin has high LC₅₀ value as 115.39 and 93.48 ppm at 1 hour while carbaryl has lowest LC₅₀ value as 514.97 and 501.59 ppm at 24 hours, respectively. In addition, the highest mortality rates after exposure show correlated with the recommendation dose of all three synthetic chemical uses. Herein, carbaryl at the concentrations of 850 ppm was the most effective to control adult millipedes with 100% mortality after one hour of exposure. Moreover, fipronil at the concentration of 125 ppm at 12 hours after exposure yield 100% mortality. Meanwhile, cypermethrin at the concentration of 175 ppm held merely 83.33% mortality after exposure for 12 hours. The recovering evidence of millipedes after intake cypermethrin was also observed. Thus, use of carbaryl and fipronil are recommended as promised effective insecticide for controlling the emerging of millipede swarming.