A pesticide formulation for controlling powdery mildew on mulberry trees

Abstract

This invention belongs to the field of pesticide technology, specifically to a pesticide formulation for controlling powdery mildew on mulberry trees. The pesticide formulation for controlling powdery mildew on mulberry trees uses a binary compound of copper oxychloride and pyraclostrobin or fluopyram as its active ingredient. The active ingredient in this pesticide formulation has a significant synergistic effect, which can improve efficacy, reduce dosage, lower disease control costs, and reduce pesticide residues and environmental pollution.

Description

Technical Field

[0001] This invention belongs to the field of pesticide technology, specifically relating to a pesticide formulation for controlling powdery mildew on mulberry trees. Background Technology

[0002] Mulberry powdery mildew is one of the most serious diseases affecting mulberry trees. Depending on the location of the powdery mildew, it is divided into two types: internal powdery mildew and external powdery mildew. Internal powdery mildew is caused by *Phyllactinia moricola*, which produces white powdery spots on the underside of mulberry leaves, with corresponding pale yellowish-brown lesions visible on the upper surface. External powdery mildew is caused by *Erysiphe mori*, which primarily produces white powdery spots on the upper surface of the leaves. Mulberry powdery mildew can cause mulberry leaves to be covered with a white powdery coating, affecting the growth of the mulberry tree. Silkworms fed with infected mulberry leaves are weak and susceptible to disease, leading to reduced cocoon yield, cocoon layer weight, and cocoon layer efficiency, thus impacting the silk industry.

[0003] Currently, the control of mulberry powdery mildew still relies mainly on chemical agents, such as ethirimol, azoxystrobin, carbendazim, propiconazole, thiram, triadimefon, thiophanate-methyl, methyl thiophanate, chlorothalonil, and lime sulfur. Chemical agents can directly target the pathogen, are fast-acting, and inexpensive. However, in pest and disease control, long-term application of single-component chemical agents can easily lead to pesticide resistance, reducing the effectiveness of chemical agents. By combining different chemical pesticides and screening for synergistic effects, these shortcomings can be overcome to some extent. Therefore, screening for synergistic compound formulations against the pathogen of mulberry powdery mildew is of great significance.

[0004] Copper succinate is an organic copper fungicide. It works primarily by exchanging copper ions with potassium and hydrogen ions on the surface of pathogen cell membranes, causing protein coagulation. Simultaneously, some copper ions penetrate into the pathogen cells and bind to certain acids, affecting enzyme activity and thus exerting a bactericidal effect. Additionally, copper succinate has a stimulating effect on plant growth.

[0005] Patent application CN201810865762.6 discloses a fungicide composition containing flutianil and copper oxychloride, which can be used to control various plant diseases, preferably powdery mildew. Additionally, patent application CN201810944473.5 discloses a fungicide composition containing fluopyram and copper oxychloride, which can be used to control various plant diseases, preferably Fusarium head blight and powdery mildew.

[0006] Currently, there are no reports of copper oxychloride being combined with pyraclostrobin or fluoxastrobin.

[0007] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0008] The purpose of this invention is to provide a pesticide formulation for controlling powdery mildew of mulberry trees, which can improve the control effect on powdery mildew of mulberry trees and delay the emergence and development of drug resistance in pathogens.

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] A pesticide formulation for controlling powdery mildew of mulberry trees, wherein the active ingredient is a binary compound of copper oxychloride and pyraclostrobin or fluopyram.

[0011] Preferably, the mass ratio of copper oxychloride to pyraclostrobin is 1-20:9-1.

[0012] Preferably, the mass ratio of copper oxychloride to fluoxetine is 1-15:25-1.

[0013] Preferably, in the pesticide formulation for controlling mulberry powdery mildew, the active ingredient has a mass percentage of 0.5-70%, with the remainder being auxiliary ingredients.

[0014] Preferably, the auxiliary components are selected from one or more of the following: fillers, wetting agents, emulsifiers, binders, disintegrants, dispersants, thickeners, defoamers, antifreeze agents, and solvents.

[0015] Preferably, the formulation of the pesticide for controlling mulberry powdery mildew is an ultra-low volume liquid, wettable powder, emulsifiable concentrate, or suspension concentrate.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] (1) The active ingredients of the pesticide formulation of the present invention have a significant synergistic effect, which can improve the efficacy, reduce the dosage of the agent, reduce the cost of disease control, and reduce pesticide residues and environmental pollution.

[0018] (2) The different components in the pesticide formulation of the present invention have different mechanisms of action against pathogens, which can delay the generation and development of pathogen resistance and extend the service life of the formulation. Detailed Implementation

[0019] The technical solution of this invention patent will be clearly and completely described below.

[0020] Spore germination experiment

[0021] 1. Test bacterial solution

[0022] Mulberry leaves infected with mulberry powdery mildew were collected. In the laboratory, conidia of the mulberry powdery mildew fungus from the lesions on the underside of the leaves were swept onto the leaves of potted 'Guisangyou 11' seedlings for propagation using a brush. When new conidia were produced, they were swept off with a brush and collected in centrifuge tubes. Sterile water was added to prepare a mulberry powdery mildew fungal suspension (1×10⁻⁶). 6 (spores / mL), for later use.

[0023] 2. Test reagents

[0024] 98% copper oxychloride technical grade (Hubei Bolan Chemical Co., Ltd.), 92% pyraclostrobin technical grade (Syngenta Nantong Crop Protection Co., Ltd.), 96% fluoxastrobin technical grade (Syngenta Nantong Crop Protection Co., Ltd.).

[0025] The test reagent was dissolved in dimethyl sulfoxide and then diluted with 0.1% Tween-80 aqueous solution to prepare a single-agent stock solution. Multiple formulations were prepared, and five mass concentration gradients were set for each single-agent stock solution and formulation mixture for later use.

[0026] 3. Culture medium

[0027] Water agar medium: 20g agar, distilled water to a final volume of 1000mL, autoclave at 120℃ for 30min.

[0028] 4. Chemical treatment

[0029] Use a pipette to add 0.2 mL of the drug solution to a test tube, then add 0.2 mL of the spore suspension to the same test tube. Mix the drug solution and spore suspension thoroughly, then spread the mixture evenly onto water agar medium and incubate at 28°C. Five replicates were set up for each drug concentration, with an equal volume of 0.1% Tween-80 aqueous solution added as a blank control.

[0030] 5. Experimental Investigation

[0031] After 48 hours, the culture medium was cut into 1cm×1cm square pieces. The pieces were observed under a microscope, and those with at least 20 non-overlapping conidia were selected. The germination rate of conidia and the total number of conidia were recorded, and the relative inhibition rate of spore germination for each treatment was calculated.

[0032] 6. Calculation Method

[0033]

[0034]

[0035]

[0036] 7. Statistical Analysis

[0037] Regression analysis was performed based on the logarithmic values ​​of each agent concentration and the corresponding relative inhibition rate of spore germination, and the EC50 of each agent was calculated. 50 The values ​​were calculated, and the co-toxicity coefficient (CTC) was calculated according to Sun Yunpei's method. Then, the synergistic effect of drug combination was evaluated based on the co-toxicity coefficient (CTC value), that is, CTC≤80 indicates antagonistic effect, 80<CTC<120 indicates additive effect, and CTC≥120 indicates synergistic effect. The results are shown in Table 1-2.

[0038] Table 1. Indoor bioactivity assay of copper oxychloride and pyraclostrobin combined with *Pyrazopyr succinate* against *Sangli powdery mildew*.

[0039]

[0040]

[0041] As shown in Table 1, the co-toxicity coefficients of copper oxychloride and pyraclostrobin in the mass ratio of 1-20:9-1 against mulberry powdery mildew are all greater than 120, indicating that the combination of copper oxychloride and pyraclostrobin has a synergistic effect on the biological activity against mulberry powdery mildew.

[0042] Table 2. Indoor bioactivity assay of copper oxychloride and fluoxetine combined with mulberry powdery mildew.

[0043] Drug Name and Proportion <![CDATA[EC 50 (mg / L)]]> ATI TTI CTC Copper succinate 18.52 100.00 -- -- Fluoxetine 1.77 1046.33 -- -- Copper oxychloride 1: Fluoxetine 25 1.42 1304.23 1009.93 129.14 Copper oxychloride 1: Fluoxetine 20 0.94 1970.21 1001.26 196.77 Copper succinate 1: Fluoxetine 10 1.06 1747.17 960.30 181.94 Copper oxychloride 1: Fluoxetine 5 1.49 1242.95 888.61 139.88 Copper oxychloride 1: Fluoxetine 1 2.08 890.38 573.16 155.35 Copper succinate 5: Fluoxetine 1 4.44 417.12 257.72 161.85 Copper succinate 10: Fluoxetine 1 6.82 271.55 186.03 145.97 Copper succinate 15: Fluoxetine 1 8.53 217.12 159.15 136.43

[0044] As shown in Table 2, the co-toxicity coefficients of copper oxychloride and fluoxetine against mulberry powdery mildew were all greater than 120 when the mass ratio was 1-15:25-1, indicating that the combination of copper oxychloride and fluoxetine showed a synergistic effect on the biological activity against mulberry powdery mildew.

[0045] In summary, when copper oxychloride is combined with pyraclostrobin or fluopyram, the synergistic effect is significant, which can improve efficacy, reduce the dosage of the agent, reduce the cost of disease control, and reduce pesticide residues and environmental pollution.

[0046] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. The application of a pesticide formulation in the control of powdery mildew on mulberry trees, characterized in that, The pesticide formulation uses a binary compound of copper oxychloride and pyraclostrobin as its active ingredients; wherein, The mass ratio of copper oxychloride to pyraclostrobin is 1-20:9-1.

2. The application according to claim 1, characterized in that, In the pesticide formulation, the active ingredient has a mass percentage of 0.5-70%, with the remainder being auxiliary ingredients.

3. The application according to claim 2, characterized in that, The auxiliary components are selected from one or more of the following: fillers, wetting agents, emulsifiers, binders, disintegrants, dispersants, thickeners, defoamers, antifreeze agents, and solvents.

4. The application according to claim 1, characterized in that, The pesticide formulation is in the form of ultra-low volume liquid, wettable powder, emulsifiable concentrate, or suspension concentrate.

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