Abstract
We compared the mortality of mites between two susceptibility test methods, chemical spray and leaf dip, with bifenazate, emamectin and cyenopyrafen for the two-spotted spider mites on strawberry. When using bifenazate and cyenopyrafen, there was no difference in mortality of mites between the two methods. However, when using emamectin, the mortality by the leaf dip method was significantly lower than that by the spray method.
A new method of placing mites on the leaf of kidney beans without using a fine brush was developed. That is, a small strawberry leaf infested with mites was placed by an intact stem of kidney bean with one primary leaf for a day. Most mites on the strawberry leaf moved onto the kidney bean leaf by themselves. There after the kidney bean leaf with mites was dipped in the acaricides for five seconds. By using this placement method followed by the leaf dip method, the mortality was similar to that of normal placement method using a fine brush followed by the spray method.
