Toxicity determination and efficacy evaluation of eight pesticides against the Acalitus phloeocoptes Nalepa
The toxicity of 8 kinds of acaricides against the Acalitus phloeocoptes Nalepa was tested in laboratory by leaf dipping method,and the field efficacy test was conducted by spray method.The toxicity of eight acaricides of the Acalitus phloeocoptes Nalepa is as follows:0.5%ivermectin emulsion>22.4%spirotetramat suspension>5%avermectin suspension+30%imidacloprid suspension>5%avermectin suspension+30%imidacloprid suspension>45%hydrazine and imidacloprid suspension>20%metformin emulsion>56%avermectin and imidacloprid microemulsion>24%imidacloprid microemulsion.Among them,0.5%ivermectin emulsion has the highest toxicity to adult mites of the Acalitus phloeocoptes Nalepa,with LC50 values of 1.028 mg/L after 24 h;The indoor toxicity of 24%imidacloprid microemulsion of the Acalitus phloeocoptes Nalepa is the lowest,with LC50 values of only 16.001 mg/L after 24 h.Among them,five highly toxic acaricides were selected for field efficacy trials.The 22.4%spirotetramat suspension had the best effect,with a control effect of 82.67%after 15 days of treatment,followed by a control effect of 82.00%after 15 days of treatment with 0.5%ivermectin emulsion.22.4%spirotetramat suspension and 0.5%ivermectin emulsifiable concentrate can be promoted for rotation in production to slow down the resistance of the Acalitus phloeocoptes Nalepa.