Residual contact vial bioassay for the selection of effective acaricides against the two-spotted spider mite

Emergence of resistant two-spotted spider mite (TSSM) can induce the over usage of standard amount of acaricides and result in various side effects. Rapid resistance monitoring is essential step for the efficient management of resistant populations by enabling the selection of appropriate acaricides. Here, we evaluated the 10 acaricides to determine its suitability on residual contact vial bioassay (RCV) by using PyriF strain as standard. Five acaricides (Abamectin, monocrotophos, tebufenpyrad, bifenazate and cyflumetofen) revealed the dose-dependent mortality within 8 h, whereas other remaining acaricides (Fenbutatin oxide, fenpyroxymate, flufenoxuron, spiromesifen and etoxazole) did not. This finding suggests that the application of RCV method is limited depending on the mode of action and physicochemical properties of each acaricide. Resistance levels to five acaricides (Abamectin, monocrotophos, tebufenpyrad, bifenazate and cyflumetofen) were determined for four field populations of TSSM by using RCV diagnostic kit. All TSSM populations showed the highest sensitivity to cyflumetofen, indicating that it would be most effective in controling field populations. RCV diagnostic kit would enable to provide crucial information for choosing the most appropriate acaricides in the field.