New application of amitraz

Abstract

The invention discloses novel application of amitraz, namely application of amitraz in preparation of a deltamethrin synergist, and the killing effect of deltamethrin on aedes albopictus can be effectively improved. The invention further discloses a high-efficiency mosquito killer which comprises amitraz and deltamethrin.

Description

Technical Field

[0001] The invention belongs to the technical field of pesticides (insecticides) and relates to a new use of amitraz. Background Art

[0002] With the deepening of globalization, the spread of diseases has become an important issue in the field of global public health. Among them, diseases transmitted by mosquitoes pose a serious threat to human health. Aedes albopictus is an important vector mosquito that can spread a variety of diseases, including dengue fever, Zika virus and yellow fever. Due to its strong adaptability and wide range of transmission, Aedes albopictus has been widely distributed in many countries, posing a huge threat to human health and life. Deltamethrin (DM) is a highly effective and broad-spectrum insecticide that is widely used in agriculture and health control. Although deltamethrin has been widely used as an effective mosquito killer, Aedes albopictus has developed resistance to it, resulting in a decrease in its effectiveness in killing Aedes albopictus. In order to overcome this problem, it is necessary to find new methods to improve the insecticidal effect of deltamethrin, and the current method is to use deltamethrin enhancers. Common cypermethrin enhancers include piperonyl butoxide (PBO), diethyl maleate (DEM), tribufos (DEF), etc., but their synergistic effect has not achieved the desired effect, and piperonyl butoxide is also included in the list of Class III carcinogens published by the World Health Organization's International Agency for Research on Cancer.

[0003] Amitraz (AMZ), molecular formula is C 19 H 23 N3 is a broad-spectrum formamide acaricide, which is a moderately toxic acaricide. Its main mechanism of action is to inhibit the activity of monoamine oxidase and induce excitation of non-cholinergic synapses in the central nervous system of the mite. Amitraz is mainly used to control various mites in crops such as fruit trees, vegetables, tea, cotton, soybeans, and sugar beets. It also has a good control effect on psyllids, is effective against eggs of some lepidopteran pests, and has a certain control effect on scale insects, aphids, cotton bollworms, pink bollworms, etc. It can also control tick mites and bee mites in cattle and sheep. Summary of the invention

[0004] The purpose of the present invention is to provide a new use of amitraz and thereby propose a synergistic mosquito killer.

[0005] To achieve the above object, the present invention proposes a new use of amitraz, namely, the use of amitraz in the preparation of a cypermethrin synergist, which can effectively improve the killing effect of cypermethrin on Aedes albopictus.

[0006] Specifically, amitraz is used as a synergist when cypermethrin is used to kill larvae and adult Aedes albopictus mosquitoes, and its synergistic effect is better than the commonly used synergists, piperonyl butoxide, diethyl maleate and trifloxyphos.

[0007] The concentration of amitraz for enhancing the effect of deltamethrin is 0.2 mg / mL, so the dosage is ≥ 0.2 mg / mL, preferably 0.2-0.6 mg / mL, and most preferably 0.4 mg / mL.

[0008] The invention also provides a combined formula of a highly effective mosquito killer, which comprises the components of amitraz and deltamethrin.

[0009] In the synergistic mosquito killer, the concentration of amitraz is ≥ 0.2 mg / mL, preferably 0.2-0.6 mg / mL, and most preferably 0.4 mg / mL.

[0010] The synergistic mosquito killer also includes an organic solvent.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] 1. Amitraz can significantly improve the killing effect of deltamethrin on Aedes albopictus, and the optimal concentration of amitraz to enhance the effect of deltamethrin is 0.4 mg / mL;

[0013] 2. The use of amitraz as a synergist of cypermethrin can reduce the amount of cypermethrin used to kill larvae and adult mosquitoes of Aedes albopictus.

[0014] 3. Compared with the existing piperonyl butoxide, diethyl maleate and defoliant phosphorus synergists, amitraz has a more significant synergistic effect on cypermethrin, making the killing rate of cypermethrin against adult Aedes albopictus reach more than 90%. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The results show that different concentrations of amitraz solution enhance the effect of cypermethrin on killing adult mosquitoes of resistant strains of Aedes albopictus;

[0016] Figure 2 The mortality results of adult mosquitoes of resistant strains of Aedes albopictus treated with deltamethrin alone and in combination with amitraz are shown;

[0017] Figure 3 The results showed that the four synergists, amitraz, piperonyl butoxide, diethyl maleate and trifloxyphos, had synergistic effects on the killing of adult mosquitoes of resistant strains of Aedes albopictus by cypermethrin. DETAILED DESCRIPTION

[0018] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] Example 1 Mosquito-killing Activity Experiment of Amitraz

[0020] (1) AMZ was prepared with acetone to prepare AMZ solutions with concentrations of 0.1, 0.2, 0.4, 0.6 mg / mL and 5, 10, 20, 40, and 80 mg / L, respectively;

[0021] (2) Larval toxicity test: 1 mL of the prepared 5, 10, 20, 40, and 80 mg / L amitraz solution was respectively aspirated and dropped into 99 mL of aqueous solution containing 20 larvae (late third instar and early fourth instar); the entire experiment was maintained in a greenhouse at 25°C ± 1°C and a relative humidity of 60% to 80%. The number of larval deaths was checked after 24 h; each concentration was repeated 3 times.

[0022] (3) Adult mosquito toxicity test: 0.1, 0.2, 0.4, and 0.6 mg / mL amitraz solutions were each used in a set of biological test bottles recommended by the Centers for Disease Control and Prevention (CDC) (4 biological test bottles form a set of CDC biological test bottles); specifically, 1 mL of amitraz solution was added to each of four 250 mL biological test bottles, and the bottles were rotated to evenly coat the inner wall of the bottles with the solution, and the bottle caps were tightly closed after they were slightly air-dried; 25 female mosquitoes of the laboratory sensitive strain of Aedes albopictus that had emerged for 3 to 5 days and had not sucked blood were placed in each biological test bottle (a total of 100 mosquitoes), the bottle caps were tightly closed, and the adult mosquitoes were observed for mortality after the test was completed;

[0023] The experimental results show that 100% of the larvae and adult mosquitoes of Aedes albopictus treated with amitraz solutions of various concentrations survived, that is, amitraz had no lethal effect on the larvae and adult mosquitoes of Aedes albopictus within the above concentration range.

[0024] Example 2 Experiment on the concentration of amitraz to enhance the effect of deltamethrin

[0025] (1) Preparation of solutions: Deltamethrin (DM) and amitraz (AMZ) were prepared with acetone to prepare DM solutions with a concentration of 10 mg / L and AMZ solutions with concentrations of 0.6 mg / mL, 0.5 mg / mL, 0.4 mg / mL, 0.2 mg / mL, and 0.1 mg / mL, respectively;

[0026] (2) Experimental procedure: The CDC bioassay bottle method was used to conduct the synergistic test of the synergistic agents.

[0027] ①Evenly apply 1 mL of AMZ solution and 1 mL of acetone solution in 250 mL glass bottles with lids to prepare synergist exposure bottles and synergist control bottles, which are recorded as synergist exposure group and synergist control group;

[0028] Evenly spread 1 mL of deltamethrin solution in a 250 mL glass bottle with a lid to prepare the experimental test bottle.

[0029] Four experimental test bottles are used as one set of CDC test bottles, while one concentration of amitraz synergist synergistic experiment requires two sets of CDC test bottles for subsequent experiments;

[0030] ② Use a mouth-suction mosquito suction tube to suck 100 female mosquitoes of the resistant strain F1534S of Aedes albopictus that have not sucked blood for 3 to 5 days after emergence into the synergist exposure bottle and the synergist control bottle. After the adult mosquitoes are fully exposed in the bottles for 1 hour, the female mosquitoes in the two bottles are transferred to two sets of CDC biological test bottles for full exposure for 30 minutes. The number of adult mosquito deaths in each experimental biological test bottle is recorded, and the adult mosquito mortality rates of the synergist exposure group and the synergist control group are calculated.

[0031] (3) Statistics of adult mosquito deaths: In the rotating test bottle, if the adult mosquitoes in the bottle cannot stand normally or roll with the rotation of the bottle, they are judged as dead.

[0032] (4) Correction of adult mosquito mortality: 1 mL of acetone solution was evenly applied to four 250 mL glass bottles with lids to prepare blank control bottles, which were recorded as blank control groups. 100 female mosquitoes of the F1534S resistant strain of Aedes albopictus that had not sucked blood for 3 to 5 days after emergence were sucked into the blank control bottles using a mouth-suction mosquito tube. The mosquitoes were fully exposed for 30 min. The number of adult mosquito deaths in each blank control bottle was recorded, and the adult mosquito mortality rate was calculated.

[0033] If the mortality rate of the blank control group is less than 3%, the experimental data does not need to be corrected; if the mortality rate of the blank control group is greater than 10%, the experimental data is invalid and retested; if the mortality rate of the blank control group is 3% to 10%, the experimental data is corrected using the Abbot formula.

[0034] The experimental results are as follows Figure 1 As shown in the figure, the concentration of AMZ that produces a synergistic effect on DM is 0.2 mg / mL. When the AMZ concentration reaches 0.4 mg / mL, the mortality rate reaches a maximum of 90%, and higher concentrations can no longer increase the toxicity of DM to mosquitoes. This is because the mosquitoes used in the experiment are the F1534S resistant strain of Aedes albopictus with a kdr mutation, which has target resistance. Therefore, the synergistic concentration of AMZ for deltamethrin is ≥ 0.2 mg / mL, and the optimal synergistic concentration is 0.4 mg / mL.

[0035] Example 3 Experiment on the synergistic effect of amitraz on deltamethrin in killing Aedes albopictus larvae

[0036] (1) Set up a control group and an experimental group of Aedes albopictus sensitive strains:

[0037] The control group observed the death of 20 sensitive strains of Aedes albopictus larvae in 100mL aqueous solution containing 0.001, 0.002, 0.004, 0.008, 0.016, and 0.020mg / L deltamethrin; the experimental group added 0.4mg / L amitraz solution to the aqueous solution on the basis of the control group, and observed the death of 20 sensitive strains of larvae in the aqueous solution after 24h. The experiment was repeated 3 times with different concentrations of deltamethrin.

[0038] (2) Setting up a control group and an experimental group of resistant strains of Aedes albopictus:

[0039] The control group observed the death of 20 resistant strains of Aedes albopictus larvae in 100mL aqueous solution containing 0.025, 0.05, 0.10, and 0.20mg / L deltamethrin; the experimental group added 0.4mg / L amitraz solution to the aqueous solution on the basis of the control group, and observed the death of 20 resistant strains of larvae in the aqueous solution after 24h. The experiment was repeated 3 times with different concentrations of deltamethrin.

[0040] (3) SPSS software was used to analyze the experimental results, and the log-probit model was used to obtain the median lethal concentration (LC50) of deltamethrin in the control group and experimental group of the sensitive and resistant strains of Aedes albopictus larvae. 50 ), calculate the synergistic multiple SR, SR = LC 50对照 / LC 50实验 .

[0041] The experimental results are shown in Table 1. Amitraz has a significant effect on reducing the LC of both sensitive and resistant strains of Aedes albopictus larvae. 50 The effect of LC on the larvae of the susceptible strain of Aedes albopictus 50 The LC of resistant strain larvae decreased from 0.0042 mg / L to 0.00072 mg / L. 50 From 0.064mg / L to 0.033mg / L; the synergistic multiple of amitraz to the sensitive strain larvae of Aedes albopictus is 5.83, and the synergistic multiple of amitraz to the resistant strain larvae is 1.94. Therefore, amitraz has a synergistic effect on the killing of Aedes albopictus larvae by cypermethrin, and can reduce the amount of cypermethrin used to kill larvae.

[0042] Table 1 The synergistic effect of amitraz on the killing of Aedes albopictus larvae by cypermethrin

[0043]

[0044] Example 4 Experiment on the synergistic effect of amitraz on deltamethrin in killing resistant strains of Aedes albopictus

[0045] (1) In the present invention, deltamethrin (DM) and amitraz (AMZ) are respectively prepared with acetone to prepare DM solutions with concentrations of 5 and 10 mg / L and AMZ solutions with a concentration of 0.4 mg / mL.

[0046] (2) Set up control group and experimental group:

[0047] Control group 1: 5 mg / L DM solution was used alone, control group 2: 10 mg / L DM solution was used alone;

[0048] Experimental group 1: 5 mg / L DM solution + 0.4 mg / mL AMZ solution were used together, and experimental group 2: 10 mg / L DM solution + 0.4 mg / mL AMZ solution were used together;

[0049] Experimental groups 1 and 2 each need to use one synergist exposure bottle and one set of CDC bioassay bottles, while control groups 1 and 2 each need to use one synergist control bottle and one set of CDC bioassay bottles. Other experimental operations are the same as step (2) of Example 2.

[0050] (3) The operations of adult mosquito death statistics and correction of adult mosquito mortality rate are the same as steps (3) and (4) of Example 2.

[0051] The experimental results are as follows Figure 2 As shown, compared with the control group, amitraz in the experimental group significantly enhanced the killing effect of deltamethrin on adult Aedes albopictus mosquitoes. Moreover, compared with the use of 10 mg / L deltamethrin alone (control group 2), the mortality rate of amitraz combined with 5 mg / L deltamethrin (experimental group 1) on adult Aedes albopictus mosquitoes was higher, at 73.74%. In other words, the use of amitraz can reduce the amount of deltamethrin used to kill adult Aedes albopictus mosquitoes.

[0052] Example 5 Comparison of the synergistic effect of amitraz and three common synergists on deltamethrin.

[0053] (1) Four synergists, amitraz (AMZ), piperonyl butoxide (PBO), diethyl maleate (DEM), and defoliate (DEF), were prepared with acetone to prepare 0.4 mg / mL AMZ solution, 0.4 mg / mL PBO solution, 0.12 mg / mL DEF solution, and 0.08 mg / mL DEM solution, respectively; and deltamethrin (DM) was prepared with acetone to prepare a 10 mg / L deltamethrin solution;

[0054] (2) The experimental operation was the same as step (2) of Example 2, except that two sets of CDC bioassay bottles were used for a synergistic experiment;

[0055] (3) The operations of adult mosquito death statistics and correction of adult mosquito mortality rate are the same as steps (3) and (4) of Example 2.

[0056] The experimental results are as follows Figure 3 As shown, when piperonyl butoxide, diethyl maleate, trifloxyphos and deltamethrin are used in combination, the adult mosquito mortality rates are 65.59%, 63.37% and 62.86% respectively, indicating that although these three synergists have a synergistic effect, the adult mosquito mortality rates do not reach 70%; and when the synergist amitraz provided by the present invention is used in combination with deltamethrin, the adult mosquito mortality rate can reach more than 90%, which indicates that the synergistic effect of amitraz is significantly better than the three commonly used synergists.

Claims

1. Application of amitraz in the preparation of cypermethrin synergist.

2. The use according to claim 1, characterized in that: The dosage of amitraz is ≥0.2 mg / mL.

3. The use according to claim 2, characterized in that: The dosage of amitraz is 0.2-0.6 mg / mL.

4. The use according to claim 3, characterized in that: The dosage of amitraz was 0.4 mg / mL.

5. A highly effective mosquito killer, characterized in that: These include amitraz and deltamethrin.

6. The high-efficiency mosquito killer according to claim 5, characterized in that: The concentration of amitraz is ≥ 0.2 mg / mL.

7. The high-efficiency mosquito killer according to claim 6, characterized in that: The concentration of amitraz is 0.2 to 0.6 mg / mL.

8. The high-efficiency mosquito killer according to claim 7, characterized in that: The concentration of amitraz was 0.4 mg / mL.

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