Application of quinoline carboxamide compound as prodenia litura insecticidal synergist and method

Abstract

The invention belongs to the technical field of pest control, and particularly relates to application and a method of a quinoline carboxamide compound as a prodenia litura insecticidal synergist. The quinoline carboxamide compound is 2-(4-isobutylphenyl)-N-[1-(4-propylphenyl) ethyl]-4-quinoline carboxamide, and the structural formula of the quinoline carboxamide compound is shown in the description. The quinoline carboxamide compound is used for inhibiting cytochrome p450 enzyme of prodenia litura; the prodenia litura cytochrome p450 enzyme is a CYP6AE48 enzyme, and the prodenia litura cytochrome p450 The compound can well inhibit the activity of a prodenia litura CYP6AE48 enzyme, so that the prodenia litura CYP6AE48 enzyme cannot normally play a role in detoxifying lambda-cyhalothrin, the control effect of lambda-cyhalothrin is further improved, and the compound can be used as a pesticide synergist to play a synergistic role in pest control.

Description

Technical Field

[0001] The present invention belongs to the technical field of pest control, and particularly relates to the use and method of quinoline carboxamide compounds as insecticidal synergists for Spodoptera litura. Background Art

[0002] Spodoptera litura ( Spodoptera litura Fabricius) belongs to the order Lepidoptera ( Lepidoptera ) Noctuidae ( No- ctuidae ) and is a polyphagous pest, which has the characteristics of wide distribution, voracious feeding, many host plants, and serious generation overlapping.

[0003] At present, Spodoptera litura has developed varying degrees of resistance to a variety of common chemical agents. The control measures for Spodoptera litura at home and abroad still mainly rely on chemical pesticides. Long-term, large-scale, frequent, and unreasonable use of pesticides has led to varying degrees of resistance of Spodoptera litura to various types of agents. In addition, chemical control will also cause environmental pollution, kill other natural enemy populations in the natural environment, and cause ecological imbalance.

[0004] The insect cytochrome P450 enzyme system (Cytochrome P450 monooxygenase) is a class of multifunctional oxidases, belonging to the cytochrome superfamily, and is widely distributed in the endoplasmic reticulum and mitochondria of insect cells. This enzyme system uses heme as a prosthetic group and undertakes various key physiological functions in insects, including metabolizing endogenous substances (such as hormones), detoxifying exogenous toxins (such as plant secondary metabolites and insecticides), and participating in the electron transfer of the respiratory chain. The main reason for the resistance of harmful insects to chemical agents is the action of P450 enzymes related to metabolism. Therefore, it is crucial to develop agents or insecticide synergists that can inhibit the activity of P450 enzymes related to insect detoxification metabolism, which can significantly reduce the resistance of insects to pesticides and enhance the control effect. Summary of the Invention

[0005] In order to enrich the types of existing pesticide synergists and further enhance the pest control effect, the present invention uses Spodoptera litura CYP6AE48 enzyme (a P450 enzyme related to detoxification metabolism) as the main target, screens a quinoline carboxamide compound, and proves that this compound has a promoting or enhancing effect on the control effect of lambda-cyhalothrin.

[0006] In order to achieve this technical purpose, the present invention adopts the following technical solutions.

[0007] Use of a quinoline carboxamide compound as a pesticide synergist, wherein the quinoline carboxamide compound is 2-(4-isobutylphenyl)-N-[1-(4-propylphenyl)ethyl]-4-quinoline carboxamide, and the structural formula of the quinoline carboxamide compound is as follows: 。

[0008] Furthermore, the quinolinecarboxamide compound inhibits the cytochrome p450 enzyme of Spodoptera litura.

[0009] Furthermore, the cytochrome p450 enzyme of Spodoptera litura is CYP6AE48 enzyme.

[0010] A method for improving the chemical control effect of Spodoptera litura, the method includes: using the amide compound as an inhibitor of the cytochrome p450 enzyme of Spodoptera litura, acting on Spodoptera litura to improve the chemical control effect of Spodoptera litura; The quinolinecarboxamide compound is 2-(4-isobutylphenyl)-N-[1-(4-propylphenyl)ethyl]-4-quinolinecarboxamide.

[0011] Furthermore, the cytochrome p450 enzyme of Spodoptera litura is CYP6AE48 enzyme.

[0012] Furthermore, the quinolinecarboxamide compound is dissolved in dimethyl sulfoxide to prepare a solution with a concentration of 8-10 g / L, and the usage amount of the solution is 16-20 μg / head.

[0013] Furthermore, the chemical control is carried out using lambda-cyhalothrin for control.

[0014] Furthermore, the quinolinecarboxamide compound makes the control effect of lambda-cyhalothrin against Spodoptera litura increase by 13.68, 19.80, and 16.04 times at 24, 48, and 72 h respectively.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The present invention takes the CYP6AE48 enzyme of Spodoptera litura as the main target, and screens a quinolinecarboxamide compound, which is 2-(4-isobutylphenyl)-N-[1-(4-propylphenyl)ethyl]-4-quinolinecarboxamide. This compound makes the control effect of lambda-cyhalothrin against Spodoptera litura increase by 13.68, 19.80, and 16.04 times at 24, 48, and 72 h respectively. It shows that this compound can better inhibit the activity of the CYP6AE48 enzyme of Spodoptera litura, making it unable to normally play its detoxification function for lambda-cyhalothrin, thereby improving the control effect of lambda-cyhalothrin. This compound can be used as a pesticide synergist to play a synergistic role in pest control.

[0016] Existing P450 enzyme inhibitors (such as piperonyl butoxide) mainly inhibit P450 enzymes related to biosynthesis reactions, while P450 enzymes related to detoxification metabolism are the main reasons for the resistance and cross-resistance of most pests to pesticides, which is more important for pest control. The present invention targets the P450 enzyme CYP6AE48 related to the detoxification metabolism of Spodoptera litura, and screens out a P450 enzyme inhibitor related to detoxification metabolism, making up for the technical defect of the relative lack of such enzyme inhibitors, which has important inspiration and guiding significance for the future research of pesticide synergists. Description of the Drawings

[0017] Figure 1 It is a molecular docking result diagram of CYP6AE48 enzyme and quinoline carboxamide compounds. Detailed Implementation Modes

[0018] The present invention will be described below in conjunction with the embodiments. The technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0019] The experimental methods in the following embodiments are all conventional methods unless otherwise specified, and are carried out according to the techniques or conditions described in the literature in this field or according to the product specifications. The materials, reagents, etc. used in the following embodiments can be obtained from commercial channels unless otherwise specified.

[0020] In the following embodiments, the quinoline carboxamide compound is: 2-(4-isobutylphenyl)-N-[1-(4-propylphenyl)ethyl]-4-quinoline carboxamide (purity is 99%), and this compound is purchased from SPECS company. The structural formula of the quinoline carboxamide compound is as follows: .

[0021] In the present invention, the larvae of Spodoptera litura are independently cultured by the Laboratory of Environment-Friendly Pesticides of Sichuan Agricultural University.

[0022] Example 1: This example describes the killing effect of lambda-cyhalothrin alone on Spodoptera litura.

[0023] Test method: Weigh the lambda-cyhalothrin technical, prepare a 1 g / L mother liquor with acetone as the solvent, and then dilute it to 3, 2, 1.5, 1, 0.5 mg / L respectively to obtain lambda-cyhalothrin solutions.

[0024] Using the 3rd instar larvae of Spodoptera litura as test insects, the beta-cyhalothrin solution was dropped onto the pronotum of the larvae with a microapplicator, 1 μL for each larva. After natural air drying, the larvae were placed in an incubator with a temperature of 27 ± 1 °C, a relative humidity of 70%, and a light duration of 12 h. Acetone was used as the control group, and the remaining treatment steps were the same. 20 larvae were treated in each petri dish, with 3 replicates. The results were observed at 24, 48, and 72 h respectively, and the number of dead insects was recorded. The larvae were considered dead if they did not wriggle when gently touched with a brush. The DPS 9.01 software was used to calculate the toxicity regression equation, correlation coefficient, and LC 50 .

[0025] Test results: See Table 1; when using beta-cyhalothrin alone at 24, 48, and 72 h, the LC 50 values were 2.9217, 2.8312, and 1.8497 mg / L respectively.

[0026] Table 1. Usage effect of using beta-cyhalothrin alone

[0027] Example 2: This example describes the usage effect of using the quinoline carboxamide compound as a synergist when using beta-cyhalothrin.

[0028] Test method: Weigh the technical beta-cyhalothrin, and prepare a stock solution of 1 g / L with acetone as the solvent, and then dilute it to 0.5, 1, 1.5, 2, and 3 mg / L to obtain the beta-cyhalothrin solution. Separately, using dimethyl sulfoxide as the solvent, prepare the quinoline carboxamide compound with a concentration of 8 - 10 g / L.

[0029] Using the 3rd instar larvae of Spodoptera litura as test insects, the solution of the quinoline carboxamide compound was dropped onto the pronotum of the larvae with a microapplicator, 16 - 20 μg for each larva. After natural air drying for 1 h, the beta-cyhalothrin solution was dropped in the same way, 1 μL for each larva. After dropping, the larvae were placed in an incubator with a temperature of 27 ± 1 °C, a relative humidity of 70%, and a light duration of 12 h. In the control group, dimethyl sulfoxide was used to replace the solution of the amide compound, and the remaining treatment steps were the same. 20 larvae were treated in each petri dish, with 3 replicates. The results were observed at 24, 48, and 72 h respectively, and the number of dead insects was recorded. The larvae were considered dead if they did not wriggle when gently touched with a brush. The DPS 9.01 software was used to calculate the toxicity regression equation, correlation coefficient, and LC 50 , and calculate the synergistic ratio (SR).

[0030] Synergistic ratio (SR) = LC of beta-cyhalothrin when used alone 50 / LC of beta-cyhalothrin when the quinoline carboxamide compound is used as a synergist 50 Test results: See Table 2; When using lambda-cyhalothrin with quinoline carboxamide compounds as synergists at 24, 48, and 72 h, the LC 50 values are 0.2136, 0.1430, and 0.1153 mg / L respectively.

[0031] Table 2. Usage effect of lambda-cyhalothrin when quinoline carboxamide compounds are used as synergists

[0032] As can be seen from Table 1 and Table 2, at 24, 48, and 72 h, the LC 50 values of lambda-cyhalothrin when adding the quinoline carboxamide compounds are significantly lower than the LC 50 when using lambda-cyhalothrin alone, indicating that the CYP6AE48 enzyme of Spodoptera litura is inhibited by the quinoline carboxamide compounds and cannot normally exert its detoxification function on lambda-cyhalothrin. Therefore, the effect of using lambda-cyhalothrin when adding the quinoline carboxamide compounds is better and meets the expectations. In addition, at 24, 48, and 72 h, the synergistic multiples are 13.68, 19.80, and 16.04 times respectively, all greater than 1, indicating that the usage effect of the quinoline carboxamide compounds is good.

[0033] Example 3: This example describes the usage effect of piperonyl butoxide as a synergist when using lambda-cyhalothrin.

[0034] Test method: Weigh the original drug of lambda-cyhalothrin and prepare a stock solution of 1 g / L with acetone as the solvent, and then dilute it to 0.5, 1, 1.5, 2, 3 mg / L to obtain lambda-cyhalothrin solutions. In addition, use dimethyl sulfoxide as the solvent to prepare a piperonyl butoxide solution with a concentration of 8 - 10 g / L.

[0035] Using the 3rd instar larvae of Spodoptera litura as test insects, use a micropipettor to drip piperonyl butoxide on the pronotum of the larvae, 16 - 20 μg per larva. After natural air drying for 1 h, drip the lambda-cyhalothrin solution in the same method, 1 μl per larva. After dripping, put them into an incubator, the temperature of the incubator is 27 ± 1 °C, the relative humidity is 70%, and the light duration is 12 h. The control group uses dimethyl sulfoxide to replace piperonyl butoxide, and the remaining treatment steps are the same. Each petri dish is treated with 20 larvae, repeated 3 times. Observe the results after 24, 48, and 72 h respectively, record the number of dead insects, and gently touch the larvae with a brush. If they do not wriggle, they are regarded as dead. Use DPS 9.01 software to calculate the virulence regression equation, correlation coefficient, and LC 50 and calculate the synergistic ratio (SR).

[0036] Synergistic ratio (SR) = LC 50 when using lambda-cyhalothrin alone / LC of lambda-cyhalothrin when using piperonyl butoxide as a synergist50 Test results: See Table 3; At 24, 48, and 72 h, when piperonyl butoxide was used as a synergist, the LC 50 values of lambda-cyhalothrin were 0.5338, 0.4553, and 0.3509 mg / L, respectively.

[0037] Table 3. Efficacy of lambda-cyhalothrin when piperonyl butoxide was used as a synergist

[0038] As can be seen from Table 2 and Table 3, at 24, 48, and 72 h, the LC 50 of lambda-cyhalothrin with the addition of piperonyl butoxide was higher than that of lambda-cyhalothrin with the addition of quinoline carboxamide compounds. 50 This indicates that the effect is better when quinoline carboxamide compounds are used as synergists. Calculated from Table 1 and Table 3, at 24, 48, and 72 h, the synergistic ratios of lambda-cyhalothrin with the addition of piperonyl butoxide were 5.47, 6.22, and 5.27, respectively, all less than the synergistic ratios when quinoline carboxamide compounds were used as synergists, which can also prove the above conclusion.

[0039] In summary, the present invention uses Spodoptera litura CYP6AE48 enzyme as the main target and screens out a quinoline carboxamide compound, which is 2-(4-isobutylphenyl)-N-[1-(4-propylphenyl)ethyl]-4-quinoline carboxamide. Molecular docking results show that there are van der Waals forces, Conventional Hydrogen Bond, Pi-sigma, Alkyl, and Pi-Alkyl between the quinoline carboxamide compound and CYP6AE48 enzyme; as Figure 1 shown, threonine (THR) 403, lysine (LYS) 32, glutamate (GLU) 69, valine (VAL) 33, leucine (LEU) 405, glycine (GLY) 404, and glutamine (GLN) 30 in CYP6AE48 enzyme bind to the compound through van der Waals forces. Lysine (LYS) 406 in this enzyme binds to the compound through Conventional Hydrogen Bond. Tyrosine (TYR) 71 in this enzyme binds to the compound through Pi-sigma. Proline (PRO) 34 and proline (PRO) 70 in this enzyme bind to the compound through Alkyl. Lysine (LYS) 31 in this enzyme binds to the compound through Pi-Alkyl.

[0040] It is known through experiments that the compound has a good inhibitory effect on the CYP6AE48 enzyme of Spodoptera litura, preventing its degradation of lambda-cyhalothrin, and is expected to play a synergistic role as a pesticide synergist in pest control.

[0041] The above-described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. The detailed description of the embodiments of the present invention is not intended to limit the scope of the present invention claimed, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art under the conditions of the present invention's concept and through relevant deductions and substitutions without creative efforts fall within the scope of protection of the present invention.

Claims

1. Use of a quinoline carboxamide compound as a pesticide synergist, characterized in that, The quinolinecarboxamide compound is 2-(4-isobutylphenyl)-N-[1-(4-propylphenyl)ethyl]-4-quinolinecarboxamide, and the structural formula of the quinolinecarboxamide compound is as follows: 。 2. The use according to claim 1, characterized in that, The quinolinecarboxamide compound inhibits the cytochrome p450 enzyme of Spodoptera litura.

3. The use according to claim 2, characterized in that, The cytochrome p450 enzyme of Spodoptera litura is CYP6AE48 enzyme.

4. A method for improving the chemical control effect of Spodoptera litura, characterized in that, The method includes: using the amide compound as an inhibitor of the cytochrome p450 enzyme of Spodoptera litura and acting on Spodoptera litura to improve the chemical control effect of Spodoptera litura; The amide compound is 2-(4-isobutylphenyl)-N-[1-(4-propylphenyl)ethyl]-4-quinolinecarboxamide.

5. The method according to claim 4, characterized in that, The cytochrome p450 enzyme of Spodoptera litura is CYP6AE48 enzyme, and it has been found that this enzyme can decompose phytotoxins and environmental pollutants and reduce their toxicity.

6. The method according to claim 4, wherein The amide compound is dissolved in dimethyl sulfoxide to prepare a solution with a concentration of 8-10 g / L, and the usage amount of the solution is 16-20 μg / head.

7. The method according to claim 4, characterized in that, The chemical control is to use lambda-cyhalothrin for control.

8. The method according to claim 7, wherein The quinolinecarboxamide compound increases the control effect of lambda-cyhalothrin against Spodoptera litura by 13.68, 19.80, and 16.04 times at 24, 48, and 72 h, respectively.

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