Toxicity test and field efficacy of 5 kinds of acaricides against Oligonychus litchii

The toxicities and field control effects of abamectin, pyridaben, hexythiazox, spirodiclofen and etoxazole against Oligonychus litchii were tested by Potter-spraying method and field efficacy trials. The results showed that the LC50 of abamectin and pyridaben to Oligonychus litchii adults were 0.18799 mg/L and 1.05426 mg/L, respectively. These 3 acaricides, hexythiazox, spirodiclofen and etoxazole, had no toxicity to Oligonychus litchii adults. Field efficacy trials showed that 5% abamectin EC, 15% pyridaben EC and 5% pyridaben EC had ready availability on Oligonychus litchii, but 240 g/L spirodiclofen SC and 110 g/L etoxazole SC were less ready availability. After 2 days, the treatment of 15% pyridaben EC diluted 1 765 times had the highest control effect (90.00%), and 110g/L etoxazole SC diluted 6 500 times had the worst control effect (57.04%). Control effects of the acaricides treatments were all above 89% after 7 days. After 15 days, all of the treatments of acaricides爷control effects were 100.00%, except the treatments of 5% abamectin EC, and the 5% abamectin EC diluted 8 333 times had the worst control effect (91.31%). All these 5 kinds of acaricides could meet the control requirements and had a long effective duration, so they could be used to control Oligonychus litchii.