Nano insecticide as well as preparation method and application thereof
Nanopesticides loaded with active ingredients of insecticides using ZIFs series nanomaterials inhibit the expression of ABC transporter genes in pests, thus solving the problem of pest resistance and achieving efficient use and environmental friendliness of insecticides.
Patent Information
- Application Number
- CN202510684903.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-26
- Publication Date
- 2025-09-16
AI Technical Summary
Existing technologies are difficult to effectively inhibit the expression of ABC transporter genes in pests, which leads to pests developing resistance to pesticides and cannot fundamentally solve the problem of pest resistance.
ZIFs series nanomaterials are used to load the active ingredients of insecticides to form nanopesticides with porous crystal structures, which enhance the toxicity of insecticides by inhibiting the expression of pest ABC transporter genes.
It significantly improves the sensitivity of resistant pests to pesticides, with an efficiency enhancement ratio of 2 to 5 times, reduces the use of chemical pesticides, lowers the risk of residues, and is suitable for a variety of pest species.
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Figure CN120642827A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to a nanopesticide, a preparation method and application thereof, and specifically to a nanopesticide for inhibiting the expression of ABC transporter genes in pests, a preparation method thereof and application thereof in the control of pesticide-resistant pests, belonging to the technical field of pesticide formulations. Background Art
[0002] In the field of agricultural pest control, insecticide resistance has become a key challenge hindering sustainable agricultural development. With the long-term and extensive use of pesticides, pests have gradually developed resistance to a variety of pesticides, leading to severe crop losses, pest control failures, and increased pesticide residues. According to the Insecticide Resistance Action Committee, over 1,000 pest species worldwide have developed resistance to one or more pesticides, and the rate of resistance development far outstrips the development of new pesticides, creating a vicious cycle.
[0003] The mechanisms of insecticide resistance in pests are complex, and ABC transporters play a crucial role in their defense against insecticides. ABC transporters, one of the largest families of membrane proteins in organisms, are widely distributed throughout insect tissues and are responsible for the absorption, distribution, and excretion of insecticides and exogenous substances. Studies have shown that upregulated expression of ABC transporter genes in many insect pests is closely associated with the development of insecticide resistance. However, currently, limited regulatory approaches are available for ABC transporters in pests, making it difficult to effectively inhibit their expression and, consequently, to fundamentally address the problem of insecticide resistance.
[0004] Traditional pesticide research and development has primarily focused on identifying new active chemical ingredients or improving formulations, but these approaches often struggle to overcome pest resistance. Furthermore, while some existing nanopesticides have made some progress in improving efficacy and reducing pesticide dosage, most fail to precisely regulate key mechanisms of pest resistance, effectively addressing pest resistance to existing pesticides. Therefore, developing novel pesticides and their preparation methods that can effectively inhibit the expression of ABC transporter genes in pests, enhance insecticide toxicity, and overcome pest resistance is crucial for the sustainable management of agricultural pests. Summary of the Invention
[0005] The technical problem to be solved by the present application is to overcome the defects of the prior art. The present application provides a nanopesticide and its preparation method and application to improve the sensitivity of resistant pests to the pesticide.
[0006] In order to solve the above technical problems, the present application provides a nanopesticide and its preparation method and application.
[0007] In the first aspect, the present application provides a nanopesticide, wherein the nanopesticide is composed of a ZIFs series nanomaterial loaded with an active ingredient of the insecticide. or The nanopesticide is a metal ion that self-assembles with an imidazole organic ligand to form a porous crystal structure; the nanopesticide enhances the toxicity of the pesticide by inhibiting the expression of the pest ABC transporter gene.
[0008] In combination with the first aspect, further, the ZIFs series nanomaterials have a particle size of 10 to 1000 nm, a pore size of 0.1 to 10 nm, and a specific surface area of 100 to 1000 m² / g.
[0009] Further, the ZIFs series nanomaterials include ZIF-1, ZIF-2, ZIF-4, ZIF-5, ZIF-7, ZIF-8, ZIF-9, ZIF-10, ZIF-11, ZIF-12, ZIF-14, ZIF-20, ZIF-23, ZIF-60, ZIF-61, ZIF-62, ZIF-64, ZIF-65, Z IF-67, ZIF-68, ZIF-69, ZIF-70, ZIF-71, ZIF-72, ZIF-73, ZIF-74, ZIF-75, ZIF-77, Z Any one or more of IF-78, ZIF-90, ZIF-95, ZIF-100, ZIF-224, ZIF-268, Zn / Co-ZIF and nZIF-8.
[0010] Furthermore, the active ingredient of the insecticide is loaded in the ZIFs series nanomaterials by physical adsorption or chemical bonding, wherein the loading rate is 5%-50%.
[0011] In a second aspect, the present application provides a method for preparing a nanopesticide, comprising:
[0012] Weigh the active ingredients of the insecticide and salt or The salt is dissolved in the solvent and stirred and mixed in advance to obtain a mixed solution;
[0013] Weighing an imidazole organic ligand and dissolving it in a solvent to obtain an imidazole organic ligand solution;
[0014] The imidazole organic ligand solution is added dropwise to the mixed solution at a uniform speed while stirring;
[0015] After the dropwise addition is completed, the reaction is continued until the reaction product is obtained;
[0016] The reaction product is post-processed to obtain the nanopesticide.
[0017] Furthermore, the solvent is a mixture of any one or more of N,N-dimethylformamide, dimethyl sulfoxide, methanol, ethanol, and water.
[0018] Furthermore, the pre-stirring and mixing time is 1 to 30 minutes, and the stirring speed is 300 to 500 rpm;
[0019] During this period, the stirring speed was maintained at 500-600 rpm;
[0020] After the dropwise addition is completed, the reaction temperature is continued at 20° C. to 80° C., and the reaction time is 15 minutes to 24 hours.
[0021] In a third aspect, the present application provides an application of a nanopesticide in preventing and controlling drug-resistant pests, wherein the drug-resistant pests include but are not limited to brown planthoppers, aphids, and diamondback moths.
[0022] In a fourth aspect, the present application provides an application of a nanopesticide in improving the toxicity of an insecticide, characterized in that the nanopesticide inhibits the expression of an insect ABC transporter gene, wherein the insect ABC transporter gene includes the NlABCG3 gene and / or the NlABCH1 gene.
[0023] In a fifth aspect, the present application provides an application of a nanopesticide, which includes spraying the nanopesticide on the surface of crops or using it as a seed treatment agent.
[0024] Beneficial effects achieved by this application:
[0025] This application provides a nanopesticide based on ZIFs nanomaterials, which responds to the acidic environment in the pest body or the stimulation of specific biomolecules to achieve intelligent controlled release of the pesticide and prolong the duration of its efficacy.
[0026] This nanopesticide significantly increases the sensitivity of resistant pests to pesticides by inhibiting the expression of ABC transporter genes, with an enhancement ratio of 2 to 5 times.
[0027] The present application provides a preparation method of a nanopesticide, which has a simple method, mild reaction conditions, and is easy to use. It effectively reduces the amount of chemical pesticides used, reduces the risk of residues, and meets the requirements of green agricultural development.
[0028] The nanopesticide prepared in this application is suitable for a variety of pesticides and pest types and has wide promotion and application value. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Figure 1 This is a scanning electron microscope characterization image of the Din@ZIF-90 nanopesticide provided in the examples of this application;
[0030] Figure 2 is the particle size distribution diagram of Din@ZIF-90 nanopesticide;
[0031] Figure 3This is the X-ray diffraction pattern of Din@ZIF-90 nanopesticide;
[0032] Figure 4 This is the Fourier transform infrared spectrum of Din@ZIF-90 nanopesticide;
[0033] Figure 5 This is the thermogravimetric analysis diagram of Din@ZIF-90 nanopesticide;
[0034] Figure 6 Cumulative release curves of dinotefuran in Din@ZIF-90 nanopesticide under different conditions;
[0035] Figure 7 The graph shows the biological activity results of Din-R of the brown planthopper resistant to dinotefuran under different pesticide treatments;
[0036] Figure 8 This is a graph showing the difference in ABC transporter gene expression levels between the susceptible brown planthopper Sus and the dinotefuran-resistant brown planthopper Din-R.
[0037] Figure 9 This is a diagram showing the effect of Din@ZIF-90 nanopesticide on the expression of ABC transporter genes in brown planthoppers;
[0038] Figure 10 Functional analysis diagram of NlABCG3, NlABCG5 and NlABCH1. DETAILED DESCRIPTION
[0039] The present application will be further described below in conjunction with the following examples. The following examples are only used to more clearly illustrate the technical solutions of the present application and are not intended to limit the scope of protection of the present application.
[0040] The present application provides a nanopesticide and its preparation method and application, wherein the preparation method comprises the following steps:
[0041] (1) Weigh the active ingredients of the insecticide and salt or The salt is dissolved in the solvent and stirred and mixed in advance to obtain a mixed solution;
[0042] (2) Weighing an imidazole organic ligand and dissolving it in a solvent to obtain an imidazole organic ligand solution;
[0043] (3) Add the imidazole organic ligand solution dropwise to the mixed solution at a uniform rate while stirring;
[0044] (4) After the dropwise addition is completed, the reaction is continued until the reaction product is obtained;
[0045] (5) Post-treating the reaction product to obtain the nanopesticide. The post-treatment includes centrifugal washing and drying. The centrifugal washing is performed at a speed of 14,000 to 16,500 rpm for 10 to 20 minutes. The drying is performed under vacuum conditions at 65 to 80°C for 16 to 24 hours.
[0046] In the above steps, the solvent is a mixture of any one or more of N,N-dimethylformamide, dimethyl sulfoxide, methanol, ethanol, and water.
[0047] The pre-mixing time is 1 to 30 minutes at a stirring speed of 300 to 500 rpm; the stirring speed is maintained at 500 to 600 rpm. After the above step of dropwise addition is completed, the reaction is continued at a temperature of room temperature to 80°C for a reaction time of 15 minutes to 24 hours.
[0048] The nanopesticide prepared according to the above method is composed of ZIFs series nanomaterials loaded with insecticide active ingredients. Specifically, the insecticide active ingredients are loaded in the ZIFs series nanomaterials by physical adsorption or chemical bonding, wherein the loading rate is 5%-50%.
[0049] The ZIFs series of nanomaterials are or The ZIFs are metal ions that self-assemble with imidazole organic ligands to form a porous crystal structure. The ZIFs series of nanomaterials have a particle size of 10 to 1000 nm, a pore size of 0.1 to 10 nm, and a specific surface area of 100 to 1000 m² / g.
[0050] The ZIFs series nanomaterials selected in the embodiments of this application include ZIF-1, ZIF-2, ZIF-4, ZIF-5, ZIF-7, ZIF-8, ZIF-9, ZIF-10, ZIF-11, ZIF-12, ZIF-14, ZIF-20, ZIF-23, ZIF-60, ZIF-61, ZIF-62, ZIF-64, ZIF-65, ZIF-67, ZIF-68, ZIF-69, ZIF-70, ZIF-71, ZIF-72, ZIF-73, ZIF-74, ZIF-75, ZIF-77, Any one or more of ZIF-78, ZIF-90, ZIF-95, ZIF-100, ZIF-224, ZIF-268, Zn / Co-ZIF and nZIF-8.
[0051] Example 1:
[0052] This embodiment provides a method for preparing a nanopesticide for inhibiting the expression of ABC transporter genes of pests, comprising the following steps:
[0053] 1) Weigh 320 mg of dinotefuran (Din, CAS No. 165252-70-0) and 200 mg of Zn(NO₃)₂·6H₂O and dissolve them in 10 mL of methanol / water (v / v = 2 / 3) solvent. Pre-mix and stir at 300 rpm for 15 minutes.
[0054] 2) Weigh 160 mg of imidazole-2-carboxaldehyde (2-ICA) and dissolve it in 10 mL of methanol / water (v / v = 2 / 3) solvent. Heat the mixture to dissolve at 100°C for 5 minutes.
[0055] 3) Slowly and evenly add the 2-ICA solution to the mixed solution of Din and Zn(NO3)2·6H2O, maintaining a rotation speed of 500 rpm. Continue the reaction for 15 minutes after the addition is completed.
[0056] 4) Centrifuge at 16,500 rpm for 10 minutes to precipitate the reaction product. Wash the product three times with methanol / water (v / v = 2 / 3) to remove free impurities, and continue centrifugation to collect the reaction product.
[0057] 5) The obtained nanopesticide Din@ZIF-90 was obtained by vacuum drying at 65°C for 16 hours.
[0058] The scanning electron microscopy results are as follows Figure 1 As shown, the prepared Din@ZIF-90 has a typical dodecahedral crystal structure.
[0059] DLS analysis showed that the average hydrated particle size was 712.4 nm and the polydispersity index (PDI) was 0.229. Figure 2 shown.
[0060] X-ray diffraction results show that Figure 3 As shown in the figure, the X-ray diffraction pattern of Din@ZIF-90 is consistent with that of ZIF-90, indicating that the loading of Din does not affect the crystal structure of ZIF-90. In addition, no Din diffraction peak is observed in the Din@ZIF-90 pattern, confirming that Din is encapsulated in the pores of ZIF-90 rather than physically adsorbed on the surface.
[0061] Fourier transform infrared (FTIR) results showed that Figure 4 As shown, Din@ZIF-90 shows characteristic peaks of ZIF-90 and Din, such as at 1675 cm -1 and 2850cm -1 The characteristic peaks at 1231 cm-1 are attributed to the stretching vibrations of CH and CHO in ZIF-90, respectively. -1 , 1550cm-1 、1621cm -1 、3340cm -1 and 3294cm -1 , which are attributed to the stretching vibrations of -COC-, -NO2, C=N, -NH, and -HOH in Din, respectively, indicating that Din has been successfully loaded into ZIF-90.
[0062] like Figure 5 As shown, thermogravimetric analysis (TGA) showed that Din contributed 16.92% to the mass of Din@ZIF-90.
[0063] Example 2:
[0064] In this example, the nanopesticide Din@ZIF-90 prepared in Example 1 was subjected to an in vitro release assay:
[0065] The assay was performed using dynamic dialysis. The Din@ZIF-90 suspension was transferred to a dialysis bag (molecular weight cut-off: 2000 D) and dialyzed against PBS (pH = 5.0, 7.0, and 8.0) at room temperature in the dark. To investigate the ATP-stimulated response, ATP (10 mM) was added to the nanoparticle dialyzate. Ultrapure water was used as a control. At each selected time point, the supernatant was removed for analysis and supplemented with an equal volume of fresh release medium. The collected samples were filtered through a 0.22 µm membrane and analyzed by high-performance liquid chromatography.
[0066] The results are as follows Figure 6 As shown in the figure, the cumulative release curves of dinotefuran in Din@ZIF-90 nanopesticide under different conditions, where A is under phosphate buffer conditions with pH 5.0, 7.0 and 8.0, and B is under deionized water and 10 mM ATP aqueous solution. It can be seen from the figure that the release rate of Din@ZIF-90 is accelerated under acidic conditions and in the presence of ATP, showing dual corresponding release performance.
[0067] Example 3:
[0068] This example uses the nanopesticide Din@ZIF-90 prepared in Example 1 to improve the insecticidal effect, as follows:
[0069] The rice seedling immersion method was used to determine the effective concentrations of Din@ZIF-90 and Din in 0.1% Triton X-100 aqueous solution, which were 10 mg·L -1 , 20 mg·L -1 , 40 mg·L -1 、80 mg·L -1 、160 mg·L -1Third-instar nymphs of the dinotefuran-resistant brown planthopper (Naturalis lugens) Din-R were treated with a 0.1% Triton X-100 solution as a control. To eliminate the toxicity of ZIF-90 itself, the nymphs were treated with a higher concentration of ZIF-90 nanoparticles. Mortality was measured after 96 hours.
[0070] The results are shown in 7. Figure 7 The bars in the figure represent the mean ± standard error, * indicates significant difference P < 0.05, ** indicates significant difference P < 0.01; Figure 7 In the figure, A is treated with Din technical solution and Din@ZIF-90 nanopesticide, and B is treated with empty carrier ZIF-90 material. At low to high concentrations, the mortality rates of brown planthoppers in the dinotefuran technical group were 4.4%, 15.6%, 31.1%, 64.4%, and 93.3%, respectively, while the mortality rates of brown planthoppers in Din@ZIF-90 at the same dinotefuran concentrations were 6.7%, 33.3%, 68.9%, 100.0%, and 100.0%, respectively. Din@ZIF-90 nanopesticide exhibited significant synergistic effects. At concentrations as high as 960 mg·L -1 The mortality rate of brown planthoppers under the treatment of ZIF-90 with the highest concentration was not significantly different from that of the control group, indicating that the synergistic effect of Din@ZIF-90 nanopesticide on brown planthoppers is not due to the toxicity of ZIF-90 itself.
[0071] This embodiment provides a use of a nanopesticide in preventing and controlling pesticide-resistant pests, wherein the pesticide-resistant pests include but are not limited to brown planthoppers, aphids, and diamondback moths.
[0072] The nanopesticide inhibits the expression of pest ABC transporter gene, wherein the pest ABC transporter gene includes N1ABCG3 gene and / or N1ABCH1 gene.
[0073] This embodiment also provides an application of the nanopesticide, including spraying the nanopesticide on the surface of crops, or using it as a seed treatment agent.
[0074] Example 4:
[0075] This example studies the effect of the nanopesticide Din@ZIF-90 prepared in Example 1 on the expression level of the ABC transporter gene of the brown planthopper:
[0076] The expression levels of 32 ABC transporter genes in the susceptible brown planthopper (Sus) and the dinotefuran-resistant brown planthopper (Din-R) were measured, and ABC genes with significantly upregulated expression were screened. The screened ABC genes were used as candidate genes, and four treatments were set up to explore the effects of Din@ZIF-90 on the expression levels of the candidate ABC genes:
[0077] Blank treatment group (Control): 0.1% Triton X-100 aqueous solution;
[0078] ZIF-90 treatment group: concentration 120 mg·L -1 ZIF-90-0.1% Triton X-100 aqueous solution;
[0079] Din technical treatment group: concentration 20 mg·L -1 Din-0.1% Triton X-100 aqueous solution;
[0080] Din@ZIF-90 treatment group: the effective concentration of Din was 20 mg·L -1 Din@ZIF-90-0.1% Triton X-100 aqueous solution.
[0081] The results are as follows Figure 8 As shown, Figure 8 The bars in the graph represent the mean ± standard error, * indicates significant difference P < 0.05, ** indicates significant difference P < 0.01, and *** indicates significant difference P < 0.001. Compared with the sensitive strain of brown planthopper Sus, the dinotefuran-resistant strain of brown planthopper Din-R has five ABC transporter genes that are significantly upregulated (P < 0.01), namely NlABCB6, NlABCB8, NlABCG3, NlABCG5, and NlABCH1. Figure 9 As shown, Figure 9 The middle bars represent the mean ± standard error, and different letters on the bars indicate significant differences at the 0.05 level; Din@ZIF-90 treatment can significantly inhibit the expression levels of NlABCG3, NlABCG5 and NlABCH1 genes.
[0082] Example 5:
[0083] This example verifies the functions of the NlABCG3, NlABCG5 and NlABCH1 genes inhibited by the nanopesticide Din@ZIF-90 prepared in Example 1 above.
[0084] First, a feeding experiment evaluated the effects of microinjection of dsNlABCG3, dsNlABCG5, and dsNlABCH1 on target gene expression and survival in brown planthoppers (NLP). Then, a rice seedling immersion method was used to assess changes in the sensitivity of NLP to dinotefuran following microinjection of these genes. Injection of dsEGFP (purchased from Shanghai Zhisheng Yougu Biotechnology Co., Ltd.) served as a blank control.
[0085] The results are as follows Figure 10 As shown, Figure 10The bars in the graphs represent the mean ± standard error, * indicates significant difference at P < 0.05, ** indicates significant difference at P < 0.01, and ns indicates no significant difference. Figure 10 A is the relative expression level result after 48 hours of injection of dsEGFP and NlABCG3, NlABCG5, and NlABCH1; B is the survival curve of brown planthopper after injection of dsEGFP and NlABCG3, NlABCG5, and NlABCH1; C, D, and E are the results of the rice seedling immersion method to evaluate the mortality of brown planthopper after 96 hours of treatment with NlABCG3, NlABCG5, and NlABCH1;
[0086] Depend on Figure 10 As shown in Figure A, compared with the brown planthopper injected with dsEGFP, the expression levels of NlABCG3, NlABCG5 and NlABCH1 in the brown planthopper 48 hours after injection with dsNlABC were significantly reduced by 64.6%, 65.8% and 91.3%, respectively. Figure 10 Middle B shows that the survival rate of brown planthoppers injected with dsNlABCG3, dsNlABCG5 and dsNlABCH1 was not significantly different from that of the control group. -1 Under Din treatment, brown planthoppers whose NlABCG3 and NlABCH1 gene expressions were suppressed showed a significant increase in mortality. This indicates that NlABCG3 and NlABCH1 genes play an important role in the brown planthopper's resistance to dinotefuran.
[0087] The above results indicate that Din@ZIF-90 nanopesticide can inhibit the expression of NlABCG3 and NlABCH1 genes of brown planthopper and overcome the resistance of brown planthopper to dinotefuran.
[0088] The above is only a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.
Claims
1. A nanopesticide, characterized in that: The nanopesticide is composed of ZIFs series nanomaterials loaded with insecticide active ingredients. or The nanopesticide is a metal ion that self-assembles with an imidazole organic ligand to form a porous crystal structure; the nanopesticide enhances the toxicity of the pesticide by inhibiting the expression of the pest ABC transporter gene.
2. The nanopesticide according to claim 1, wherein The ZIFs series nanomaterials have a particle size of 10 to 1000 nm, a pore size of 0.1 to 10 nm, and a specific surface area of 100 to 1000 m² / g.
3. The nanopesticide according to claim 1, characterized in that The ZIFs series nanomaterials include ZIF-1, ZIF-2, ZIF-4, ZIF-5, ZIF-7, ZIF-8, ZIF-9, ZIF-10, ZIF-11, ZIF-12, ZIF-14, ZIF-20, ZIF-23, ZIF-60, ZIF-61, ZIF-62, ZIF-64, ZIF-65, ZIF- 67. ZIF-68, ZIF-69, ZIF-70, ZIF-71, ZIF-72, ZIF-73, ZIF-74, ZIF-75, ZIF-77, ZI Any one or more of F-78, ZIF-90, ZIF-95, ZIF-100, ZIF-224, ZIF-268, Zn / Co-ZIF and nZIF-8.
4. The nanopesticide according to claim 1, characterized in that The active ingredient of the insecticide is loaded in the ZIFs series nanomaterials by physical adsorption or chemical bonding, wherein the loading rate is 5%-50%.
5. A method for preparing the nanopesticide according to any one of claims 1 to 4, characterized in that: include: (1) Weigh the active ingredients of the insecticide and salt or The salt is dissolved in the solvent and stirred and mixed in advance to obtain a mixed solution; (2) Weighing an imidazole organic ligand and dissolving it in a solvent to obtain an imidazole organic ligand solution; (3) Add the imidazole organic ligand solution dropwise to the mixed solution at a uniform rate while stirring; (4) After the dropwise addition is completed, the reaction is continued until the reaction product is obtained; (5) Post-processing the reaction product to obtain the nanopesticide.
6. The preparation method according to claim 5, characterized in that The solvent is a mixture of any one or more of N,N-dimethylformamide, dimethyl sulfoxide, methanol, ethanol and water.
7. The preparation method according to claim 5, wherein The pre-stirring and mixing time is 1 to 30 minutes, and the stirring speed is 300 to 500 rpm; During this period, the stirring speed was maintained at 500-600 rpm; After the dropwise addition is completed, the reaction temperature is continued at 20° C. to 80° C., and the reaction time is 15 minutes to 24 hours.
8. Use of the nanopesticide according to any one of claims 1 to 4 in controlling drug-resistant pests, characterized in that: The pesticide-resistant pests include but are not limited to brown planthoppers, aphids, and diamondback moths.
9. Use of the nanopesticide according to any one of claims 1 to 4 for improving the toxicity of pesticides, characterized in that: The nanopesticide inhibits the expression of the pest ABC transporter gene, and the pest ABC transporter gene includes NlABCG3 Genes and / or NlABCH1 Gene.
10. A use of the nanopesticide according to any one of claims 1 to 4, characterized in that: The applications include spraying the nanopesticides on crop surfaces or using them as seed treatment agents.