A pesticide composition for treating white rot of peanut and preparation method thereof

Abstract

The present invention belongs to the technical field of pesticide preparations, and specifically relates to a pesticide composition for peanut white rot and a preparation method thereof, comprising three active ingredients, Fe2 (EDTA) 3-fluoxazolidinone nanocomposite, prothioconazole and azoxystrobin, wherein the mass ratio of the Fe2 (EDTA) 3-fluoxazolidinone nanocomposite, prothioconazole and azoxystrobin is 6-8:1:1. The pesticide composition for peanut white rot in the present invention is obtained by complexing EDTANa2 with iron ions to obtain Fe2 (EDTA) 3, which can be used as a synergist of fluoxazolidinone to improve the bactericidal effect of fluoxazolidinone, and on the other hand, iron also plays an important role in the electron transfer of the mitochondrial respiratory chain, and can synergistically enhance the bactericidal effect of fluoxazolidinone, so as to achieve a better bactericidal effect.

Description

Technical Field

[0001] The invention belongs to the technical field of pesticide preparations, and particularly relates to a pesticide composition for treating peanut white rot and a preparation method thereof. Background Art

[0002] my country is a major peanut-growing country, with the total peanut production and export volume ranking first in the world. As the economic and nutritional value of peanuts has become more and more well-known, the domestic peanut planting area and production have also shown an increasing trend since 1970. Peanuts are easily infected by a variety of pathogens throughout the growth period, resulting in reduced peanut yields. Among them, peanut white rot is one of the major diseases that causes economic losses to peanuts. The pathogen of peanut white rot is Sclerotium sclerotiorum.

[0003] There are many types of succinate dehydrogenase inhibitors (SDHIs), which have good inhibitory effects on basidiomycetes and were originally used to control rust. In recent years, succinate dehydrogenase inhibitor fungicides have continued to develop, and their antimicrobial spectrum has been greatly expanded. For example, fluopyrabactam has a good effect in controlling peanut white rot. SDHIs fungicides mainly act on protein complex II (Succinate dehydrogenase; SDH) of the mitochondrial respiratory chain to block the energy metabolism of pathogens, ultimately achieving the purpose of inhibiting the growth and development of pathogens.

[0004] However, in the prevention and control of agricultural diseases, the efficacy and range of a single agent are limited. Different pathogens cannot infect crops at the same time during the entire crop growth period, making it difficult to achieve comprehensive and effective prevention and control. In addition, long-term use of a single agent can easily induce drug resistance, resulting in sudden prevention and control failures, which seriously affects crop yields. Therefore, it is urgent to rationally use pesticides and fungicides to prepare composites to reduce disease resistance. Summary of the invention

[0005] The object of the present invention is to provide a pesticide composition for peanut white rot and a preparation method thereof, so as to solve the problems raised in the above background technology.

[0006] In order to achieve the above technical objectives, the technical solution of the present invention is:

[0007] A pesticide composition for treating white rot of peanut comprises three active ingredients, namely, Fe2(EDTA)3-fluopyrabamide nanocomposite, prothioconazole and azoxystrobin, wherein the mass ratio of the Fe2(EDTA)3-fluopyrabamide nanocomposite, prothioconazole and azoxystrobin is 6-8:1:1, and the Fe2(EDTA)3-fluopyrabamide nanocomposite is prepared from fluopyrabamide, Fe2(EDTA)3, carboxymethyl chitosan and TAT protein transduction peptide.

[0008] As a further improvement, the mass percentage of prothioconazole in the composition is 0.6%.

[0009] As a further improvement, agriculturally acceptable auxiliary ingredients are also included, including wetting agents and fillers.

[0010] The present invention also provides a method for preparing a pesticide composition for peanut white rot, comprising the following steps:

[0011] Preparation of S1, Fe2(EDTA)3 solution;

[0012] The Fe2(EDTA)3 solution is obtained by complexing EDTANa2 with iron ions;

[0013] Preparation of S2, Fe2(EDTA)3-flupyraclostrobin nanocomposites;

[0014] The mother solution of fluopyram, Fe2(EDTA)3 solution and carboxymethyl chitosan aqueous solution were mixed, and then the TAT protein transduction peptide aqueous solution was added dropwise thereto, stirred with a magnetic stirrer at room temperature, and incubated at room temperature for 20 minutes. After the nanocomposite was formed, the solution became turbid, and the turbidity was transferred to a microcentrifuge tube, centrifuged at a speed of 12000g for 10 minutes, the upper liquid was discarded, and the Fe2(EDTA)3-fluopyram nanocomposite was obtained after drying;

[0015] S3, preparation of pesticide composition;

[0016] The Fe2(EDTA)3-flupyraclostrobin nanocomposite, prothioconazole, azoxystrobin and a filler are mixed, and then a wetting agent is added, and the mixture is evenly mixed to form a soft material, and then the soft material is passed through a sieve to form wet granules, and the pesticide composition is obtained after drying.

[0017] As a further improvement, in step S1, the preparation method of Fe2(EDTA)3 is: dissolving ferric oxide in 37% hydrochloric acid by mass, and then adding EDTANa2 thereto to obtain Fe2(EDTA)3 solution.

[0018] As a further improvement, in step S2, the method for preparing the fluopyrabamide mother solution is: using dimethyl sulfoxide as a solvent and fluopyrabamide as a solute to prepare a 1.2 mg / mL fluopyrabamide mother solution.

[0019] As a further improvement, in step S2, the concentration of the carboxymethyl chitosan aqueous solution is 1.5 mg / mL, and the concentration of the TAT protein transduction peptide aqueous solution is 1 mg / mL.

[0020] As a further improvement, the wetting agent is polyether-modified polyorganosiloxane or alkylphenol formaldehyde resin polyoxyethylene ether, and the mass percentage of the wetting agent in the pesticide composition is 0.5%.

[0021] Due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0022] The present invention provides a pesticide composition for peanut white rot, which is obtained by complexing EDTANa2 with iron ions to obtain Fe2(EDTA)3, which can be used as a synergist of fluopyrabamide to improve the bactericidal effect of fluopyrabamide, and on the other hand, iron also plays an important role in the electron transfer of the mitochondrial respiratory chain, and can synergistically enhance the bactericidal effect of fluopyrabamide, resulting in a better bactericidal effect.

[0023] In the present invention, Fe2(EDTA)3, fluopyrabamide, carboxymethyl chitosan and TAT protein transduction peptide are mixed and incubated to form a nanocomplex. When acting on pathogenic bacteria, the TAT protein transduction peptide can transduce Fe2(EDTA)3 and fluopyrabamide through the mitochondrial membrane of the pathogenic bacteria, directly act on the respiratory chain electron transfer system inside the mitochondria of the pathogenic bacteria, and prevent the rapid generation of resistance. In addition, carboxymethyl chitosan has good biocompatibility, and the product is non-toxic and can be absorbed by organisms.

[0024] TAT protein transduction peptide can transduce Fe2 (EDTA) 3 and fluopyrabamide through the mitochondrial membrane of pathogens, and then synergize Fe2 (EDTA) 3 and fluopyrabamide to affect the mitochondrial respiratory chain electron transfer system of pathogens, inhibit the transfer of electrons from mitochondrial complex II to ubiquinone in the respiratory chain, block its energy metabolism, thereby inhibiting the growth of pathogens and causing their death, ultimately achieving the purpose of preventing and controlling diseases.

[0025] The pesticide composition of the present invention not only has a good effect on peanut white rot, but also the risk of resistance of the pathogenic bacteria of peanut white rot to the pesticide composition of the present invention is low. DETAILED DESCRIPTION

[0026] The technical scheme of the present invention will be clearly and completely described below in conjunction with specific embodiments, but it will be appreciated by those skilled in the art that the following described embodiments are part of embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be considered as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work, all belong to the scope of protection of the present invention. If specific conditions are not indicated in the embodiments, they are carried out according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not indicated in the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0027] In the present invention, TAT protein transduction peptide was purchased from Hangzhou Peptidejia Biotechnology Co., Ltd., with a catalog number of 600012, a CAS number of 191936-91-1, and a purity of 98%.

[0028] Example 1 This example provides a pesticide composition for peanut white rot, comprising three active ingredients: Fe2 (EDTA) 3-fluopyrabamide nanocomposite, prothioconazole and azoxystrobin, and also comprising a wetting agent and a filler, wherein the wetting agent is a polyether-modified polyorganosiloxane, and the filler is kaolin, wherein the mass ratio of Fe2 (EDTA) 3-fluopyrabamide nanocomposite, prothioconazole and azoxystrobin is 6:1:1.

[0029] Specifically, it includes 3.6g Fe2(EDTA)3-flupyraclostrobin nanocomposite, 0.6g prothioconazole, 0.6g azoxystrobin, 0.5g polyether-modified polyorganosiloxane and 94.7g kaolin.

[0030] The preparation method of the pesticide composition of this embodiment comprises the following steps:

[0031] Preparation of S1, Fe2(EDTA)3 solution;

[0032] Dissolve 1 mol of ferric oxide in 0.5 L of 37% hydrochloric acid, and then add 1 mol of EDTANa2 to obtain Fe2(EDTA)3 solution;

[0033] S2, preparation of the mother solution of fluopyrabactam;

[0034] Using dimethyl sulfoxide as solvent and fluopyram as solute, a 1.2 mg / mL fluopyram stock solution was prepared.

[0035] Preparation of S3, Fe2(EDTA)3-flupyraclostrobin nanocomposites;

[0036] 1 mL of fluopyram mother solution, 1.38 mL of Fe2 (EDTA) 3 solution and 1 mL of 1.5 mg / mL carboxymethyl chitosan aqueous solution were mixed, and then 1 mL of 1 mg / mL TAT protein transduction peptide aqueous solution was added dropwise thereto, stirred with a magnetic stirrer at room temperature, and incubated at room temperature for 20 minutes. After the nanocomposite was formed, the solution became turbid, and the turbidity was transferred to a microcentrifuge tube, centrifuged at a speed of 12000g for 10 minutes, the upper liquid was discarded, and after drying at 65°C for 30 minutes, Fe2 (EDTA) 3-fluopyram nanocomposite was obtained;

[0037] S4, preparation of pesticide composition;

[0038] 3.6 g of Fe2 (EDTA) 3-flupyraclostrobin nanocomposite, 0.6 g of prothioconazole, 0.6 g of azoxystrobin and 94.7 g of kaolin are mixed evenly, and then 0.5 g of polyether-modified polyorganosiloxane is added and mixed evenly to form a soft material, and then the soft material is passed through a sieve to form wet granules, and then dried to obtain the pesticide composition.

[0039] Example 2 This example provides another pesticide composition for treating white rot of peanut, which specifically includes 4.8 g of Fe2(EDTA)3-fluopyrabamide nanocomposite, 0.6 g of prothioconazole, 0.6 g of azoxystrobin, 0.5 g of alkylphenol formaldehyde resin polyoxyethylene ether and 93.5 g of diatomaceous earth.

[0040] The preparation method of the pesticide composition in this example is the same as that in Example 1.

[0041] Example 3 This example uses the method of inhibiting mycelium growth rate to measure the inhibitory effect of the pesticide composition on peanut white rot. The specific method is as follows:

[0042] Prepare SNA culture medium as follows: dilute 1g K2PO4, 1g KNO3, 0.5g MgSO4·7H2O, 0.5g KCl, 0.2g glucose, and 0.2g sucrose to 1L with pure water, and stir to obtain culture solution. Add 3.2g agar powder to a 250mL conical flask, measure 200mL culture solution, mix well, and sterilize.

[0043] In this experiment, the pathogen of peanut white rot was used as the test strain.

[0044] Take 10 mL of SNA medium, add 0.05 mg of the pesticide composition prepared in Example 1 thereto, mix well, and then pour into a sterile culture dish to prepare a pesticide composition flat culture medium as a pesticide composition group;

[0045] Take 10 mL of SNA medium, add 0.05 mg of fluopyram thereto, mix well, and then pour into a sterile culture dish to prepare a fluopyram flat medium as a fluopyram group;

[0046] The blank culture medium was used as the control group.

[0047] Select the mycelium with vigorous growth, and take a 5mm diameter plate along the edge of the colony. Place the 5mm plate with the mycelium facing downward in the center of the solidified culture medium of the above three groups, and culture it in a dark incubator at 25℃ for 5 days. The colony diameter is measured by the cross method. The inhibition rate of the agent on mycelium growth is calculated according to the colony growth diameter. The calculation formula is: inhibition rate (%) = (control colony diameter - treatment colony diameter) / (control colony diameter - 5mm) × 100. This experiment was repeated three times.

[0048] The experimental results are shown in Table 1. It can be seen from Table 1 that the pesticide combination group has a better inhibitory effect on the pathogen of peanut white rot than the fluopicolide group, and the average inhibition rate is 88.14%.

[0049]

[0050] Example 4 This example detects the stability of the bactericidal effect of the pesticide composition of the present invention. The specific experimental method is as follows: the pesticide composition prepared in Example 1 is stored at 54°C for two weeks and then the experiment in Example 4 is performed again. The experimental results are shown in Table 2. It can be seen from Table 2 that after being stored at 54°C for two weeks, the inhibitory effect of the pesticide composition on the peanut white rot pathogen is basically not attenuated, indicating that the pesticide composition of the present invention has good stability.

[0051]

[0052] Example 5 This example verifies the resistance risk of the pesticide composition of the present invention to the pathogen of peanut white rot.

[0053] 10 mL of SNA medium was taken, 0.05 mg of the pesticide composition prepared in Example 1 was added thereto, mixed, and then poured into a sterile culture dish to prepare a pesticide composition flat culture medium as a pesticide composition group.

[0054] Take 10 mL of SNA medium, add 0.05 mg of fluopyram thereto, mix well, and then pour into a sterile culture dish to prepare a fluopyram flat medium as a fluopyram group.

[0055] After culturing the peanut white rot pathogen at 25°C for 2 days, a bacterial disc with a diameter of 5 mm was picked from the edge of the colony, and the bacterial disc was transferred to two groups of culture dishes of the above-mentioned pesticide combination group and the fluopyram group, respectively. 40-50 mycelium blocks were inoculated in each culture dish. After culturing at 25°C in the dark for 15 days, the colonies at the edge of the colonies with faster growth were picked and transferred to a new drug-containing culture medium. The colonies were activated and transferred in sequence for 10 generations. The colony diameter of each generation of colonies was measured by the cross method, and the inhibition rate of the pesticide combination and fluopyram on mycelium growth was calculated according to the colony growth diameter.

[0056] The experimental results are shown in Table 3. It can be seen from Table 3 that the inhibition rate of the pesticide composition on the pathogen of peanut white rot is higher than that of fluopoxadil on the pathogen of peanut white rot, and in the first three generations, the inhibition rate of the pesticide composition of the present invention on the pathogen of peanut white rot remains basically unchanged, while the inhibition rate of fluopoxadil on the pathogen of peanut white rot gradually decreases. After three generations, the inhibitory effect of fluopoxadil on the pathogen of peanut white rot drops drastically, while the inhibition rate of the pesticide composition of the present invention on the pathogen of peanut white rot tends to be stable, indicating that the risk of resistance of peanut white rot to the pesticide composition of the present invention is lower.

[0057]

[0058] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A pesticide composition for peanut white rot, characterized in that: The invention comprises three active ingredients, namely, Fe2 (EDTA) 3-fluopyrabamide nanocomposite, prothioconazole and azoxystrobin, wherein the mass ratio of the Fe2 (EDTA) 3-fluopyrabamide nanocomposite, prothioconazole and azoxystrobin is 6-8:1:1, and the Fe2 (EDTA) 3-fluopyrabamide nanocomposite is prepared from fluopyrabamide, Fe2 (EDTA 3), carboxymethyl chitosan and TAT protein transduction peptide; The preparation method of the Fe2(EDTA)3-flupyraclostrobin nanocomposite specifically comprises the following steps: Preparation of S11, Fe2(EDTA)3 solution; The Fe2(EDTA)3 solution is obtained by complexing EDTANa2 with iron ions; Preparation of S12, Fe2(EDTA)3-flupyraclostrobin nanocomposites; The mother solution of fluopyram, Fe2 (EDTA) 3 solution and carboxymethyl chitosan aqueous solution were mixed, and then the TAT protein transduction peptide aqueous solution was added dropwise thereto, stirred with a magnetic stirrer at room temperature, incubated at room temperature for 20 minutes, and after the nanocomplex was formed, the solution became turbid. The turbid material was transferred to a microcentrifuge tube and centrifuged at a speed of 12000g for 10 minutes. The upper liquid was discarded and dried to obtain the Fe2 (EDTA) 3-fluopyram nanocomplex.

2. The pesticide composition for peanut white rot according to claim 1, characterized in that: The mass percentage of prothioconazole in the composition is 0.6%.

3. The pesticide composition for peanut white rot according to claim 2, characterized in that: Also included are agriculturally acceptable adjuvant ingredients including wetting agents and fillers.

4. A method for preparing the pesticide composition for peanut white rot according to claim 3, characterized in that: The following steps are involved: Preparation of S1, Fe2(EDTA)3 solution; The Fe2(EDTA)3 solution is obtained by complexing EDTANa2 with iron ions; Preparation of S2, Fe2(EDTA)3-flupyraclostrobin nanocomposites; The mother solution of fluopyram, Fe2(EDTA)3 solution and carboxymethyl chitosan aqueous solution were mixed, and then the TAT protein transduction peptide aqueous solution was added dropwise thereto, stirred with a magnetic stirrer at room temperature, and incubated at room temperature for 20 minutes. After the nanocomposite was formed, the solution became turbid, and the turbidity was transferred to a microcentrifuge tube, centrifuged at a speed of 12000g for 10 minutes, the upper liquid was discarded, and the Fe2(EDTA)3-fluopyram nanocomposite was obtained after drying; S3, preparation of pesticide composition; The Fe2(EDTA)3-flupyraclostrobin nanocomposite, prothioconazole, azoxystrobin and a filler are mixed, and then a wetting agent is added, and the mixture is evenly mixed to form a soft material, and then the soft material is passed through a sieve to form wet granules, and the pesticide composition is obtained after drying.

5. The method for preparing the pesticide composition for peanut white rot according to claim 4, characterized in that: In step S1, the preparation method of Fe2(EDTA)3 is: dissolving ferric oxide in hydrochloric acid with a mass fraction of 37%, and then adding EDTANa2 thereto to obtain Fe2(EDTA)3 solution.

6. The method for preparing the pesticide composition for peanut white rot according to claim 4, characterized in that: In step S2, the method for preparing the fluopyram mother solution is: using dimethyl sulfoxide as a solvent and fluopyram as a solute to prepare a 1.2 mg / mL fluopyram mother solution.

7. The method for preparing the pesticide composition for peanut white rot according to claim 4, characterized in that: In step S2, the concentration of the carboxymethyl chitosan aqueous solution is 1.5 mg / mL, and the concentration of the TAT protein transduction peptide aqueous solution is 1 mg / mL.

8. The method for preparing the pesticide composition for peanut white rot according to claim 4, characterized in that: In step S3, the wetting agent is polyether-modified polyorganosiloxane or alkylphenol formaldehyde resin polyoxyethylene ether, and the mass percentage of the wetting agent in the pesticide composition is 0.5%.

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