Development And Control Efficacy Evaluation Of Several Mixed Formulations Of Botanical Aphidicidal

Aphids are characterized by large quantity,rapid propagation and strong adaptability to the environment,resulting in different degrees of resistance to frequently-used chemical insecticides.Based on the consideration of environmental protection,safety and pesticide resistance management,finding new aphicidal activity substances from natural resources is a hot spot for developing new products of aphicides,and also the main way to develop alternatives for chemical aphicides.However,the field efficacy of botanical aphicides of single constitute is often not excellent.By scientific and reasonable combination,high active botanical aphicides mixtures can be developed.In view of this,our research targets on aphicidal effect of the binary combinations of Sophora alopecuroides alkaloids,farnesol and nicotine on against the test aphid,Aphis citricola van der Goot,and the main results are as follows:（1）Contact activity of Sophora alopecuroides alkaloids,farnesol and nicotine to A.citricola van der was tested with topical application.Results showed that the LD₅₀value of Sophora alopecuroides alkaloids,farnesol and nicotine is 0.224μg/individual、0.180μg/individual、0.016μg/individual,respectively.（2）The binary combinations of nicotine and Sophora alopecuroides alkaloids（1:21,w/w）,nicotine and farnesol（1:4.82,w/w）,farnesol and Sophora alopecuroides alkaloids（1:3.21,w/w）showed significant synergy against A.citricola van der,with a common-toxicity coefficient（CTC）value of 178.20,151.63,138.90,respectively.（3）22%nicotine·SophoraalopecuroidesalkaloidsHN（22%N·SHN）,6%nicotine·farnesol HN（6%N·F HN）,22%nicotine·Sophora alopecuroides alkaloids SL（22%N·S SL）,6%nicotine·farnesol SL（6%N·F SL）were developed,and the detection of the quality indicators met the requirements of qualified pesticides.（4）Field trials indicated that 990 g a.i./hm²of 22%N·S SL maintained 87.63%control efficiency on the mixed species populations of Sitobion avenae Fabricius and Schizaphis graminum（Rondani）at 7d after spraying application,and 907.5 g a.i./hm²of 22%N·S SL maintained more than 93.27%control efficiency on A.citricola van der at 7d after spraying application;126.0 g a.i./hm²of 6%F·N SL maintained 87.80%control efficiency on the mixed species populations of Sitobion avenae Fabricius and Schizaphis graminum（Rondani）at 7d after spraying application,and 115.5 g a.i./hm²of 6%F·N SL maintained more than81%control efficiency on A.citricola van der at 7d after spraying application;0.183 g a.i./m³of 22%N·S HN maintained 89.34%control efficiency on Aphis craccivora in greenhouse;0.058 g a.i./m³of 6%N·F HN maintained 89.67%control efficiency on Aphis craccivora in greenhouse.Four new kinds of binary preparations above showed good control efficiency on A.citricola van der,Sitobion avenae Fabricius and Schizaphis graminum（Rondani）,having the potential for further development,which have been applied for the national pesticides invention patents,and have been assigned.