A project has been launched and aims to introduce Amblyseius swirskii for the control of Tetranychuns urticae in rose cultivating greenhouse. This study was intended to use selective acaricide, sensibly, to reduce risk for the natural enemy agent of A. swirskii in controlling T. urticae. T. urticae was susceptible strain UD from Entomology laboratory of SNU and A. swirskii was purchased from commercially available source. When LC50s were compared with A. swirskii and T. urticae of abamectin 1.8EC and 7 other acaricides, chlorfenapyr+cyenopyrafen (4+20)SC, abamectin 1.8EC, and chlorfenapyr 10SC for A. swirskii showed 148, 74, and 14 times, respectively, higher dose than T. urticae, as selective acaricides. However, fenpropathrin 5EC and fenpyroximate 5SC for T. urticae showed 22, and 25 times, respectively, higher dose than A. swirskii. For T. urticae bifenazate 23.5SC and cyflumetofen 20SC showed more than 97% mortality at less than the recommended dose, but the acricides did not kill A. swirskii 16 and 4 times as much dose as the recommended dose. The results suggested that several acaricides have inherent lower toxicity to A. swirskii. For practical application, it might be recommended to use acaricides in a way to strengthen inherent selectivity.

• Chung, Bu-Keun(Division of Plant Environment, Gyeongnam Agric.Res.& Extn Serv)
• Heung-Su Lee(Division of Crop Science, Gyeongnam Agric.Res.& Extn Serv)
• Byoung-Ryong Jeong(Department of Horticulture, Gyeongsang National University)