A bactericidal composition containing WML-01 and a triazole compound, preparation and application thereof

Abstract

This invention discloses a fungicide composition containing WML-01 and triazole compounds. The fungicide composition is characterized by comprising WML-01 and triazole compounds in a mass ratio of 10:1 to 1:10. The fungicide composition provided by this invention, with WML-01 and triazole agents as active ingredients, exhibits a synergistic effect in the control of rice bakanae disease, wheat stem rot, wheat scab, plant root rot, and rapeseed sclerotinia stem rot. It can effectively improve disease control efficacy, reduce pesticide usage, delay the development of pesticide resistance, and increase crop yield. It is safe, effective, and economical, and has broad market application prospects.

Description

Technical Field

[0001] This invention relates to the field of pesticide technology, specifically to a fungicide composition containing WML-01 and triazole compounds, its formulation, and its application. Background Technology

[0002] Rice bakanae disease, also known as excessive growth disease, is a significant disease affecting rice production and occurs in all major rice-producing areas of my country. The main pathogen is *Fusarium oxysporum* (Fusarium oxysporum). Fusarium fujikuroi Infected seeds and diseased plant debris in the field are the main primary sources of infection for rice bakanae disease. Infected grains often fail to germinate or emerge after sowing. Typically, infected seedlings are thinner and taller than healthy seedlings, with slender leaf sheaths, pale yellow leaves, and poor root development; some seedlings die before transplanting. After transplanting, the mycelium can spread throughout the entire plant under suitable conditions, stimulating excessive vegetative growth. During flowering, the pathogen spreads to the flowers, invading the glumes and endosperm, causing shriveled or deformed grains. If the pathogen invades late, although the grains may not show symptoms, the mycelium has already penetrated internally, making the seeds infected and affecting the planting of subsequent rice crops, causing significant damage. Chemical control remains the primary method for controlling rice bakanae disease. Currently, fungicides registered for the control of rice bakanae disease on the market include carbendazim, prochloraz, difenoconazole, and fludioxonil. However, the long-term, large-scale, and frequent use of chemical agents has led to pathogens gradually developing resistance to different fungicides, resulting in a significant reduction in the effectiveness of the agents. Increasing the amount of pesticides used will lead to problems such as pesticide residues, seed safety, and environmental pollution.

[0003] Wheat stem base rot, commonly known as "crown rot" or "dryland foot disease," is caused by Fusarium graminearum (…). Fusarium pseudograsses Fusarium graminearum ( ), Fusarium gramineae This global wheat stem rot is caused by various Fusarium fungi, including *Fusarium graminearum*, and is the dominant pathogen in major wheat-producing areas of my country. Early symptoms of stem rot cause browning and rotting of young roots or coleoptiles, leading to seedling death in severe cases. The disease then spreads to the first and second stem nodes, causing the affected areas to turn dark brown or rot, the leaf sheaths at the stem base to wither, and the stem to turn brown and necrotize. Later, the browning at the stem base hinders the transport of water from the roots to the ear, resulting in a completely white ear. After the ear forms a white head, the wheat grains cannot continue to develop, significantly impacting the grain filling rate and yield. Currently, only eight pesticides are registered for the control of this disease, including fludioxonil, tebuconazole, difenoconazole, prothioconazole, trifluralin, and thiamethoxam. There is an urgent need for new pesticides to control this disease.

[0004] Fusarium head blight, commonly known as "wheat rot," is a global wheat disease caused by various Fusarium fungi, including Fusarium graminearum. F. graminearum Fusarium head blight (FHB) is a dominant pathogen in many wheat-producing areas. It occurs throughout my country, causing seedling blight, stem rot, and ear rot. In epidemic years, the disease incidence rate often exceeds 50%, resulting not only in significantly reduced yield and deteriorated quality, but also in the presence of toxins in the diseased grains, which can cause poisoning in humans and animals. Fungicides used to control FHB in production mainly include benzimidazole fungicides, triazole fungicides, and methoxyacrylate fungicides. The long-term and extensive use of chemical fungicides has led to increasingly prominent resistance issues to the FHB fungus.

[0005] Root rot is a common disease in plant production. The pathogen mainly damages the plant roots, causing poor plant growth, seed rot, root decay, stunting, yellowing flowers, and in severe cases, death of the entire plant, leading to significant yield losses. Soybean root rot is a major root disease in soybean production. In the seedling stage, it affects seedling growth and can even cause seedling death, reducing the number of seedlings remaining in the field. In mature plants, root damage affects the growth and number of root nodules, resulting in poor above-ground growth, stunting, and reduced pod number and grain weight, thus leading to a decrease in yield. Currently, fungicides registered on the market for the control of soybean root rot include difenoconazole, prochloraz, fludioxonil, carbendazim, and thiram.

[0006] Sclerotinia stem rot is the most threatening disease to rapeseed production, and the pathogen is Sclerotinia stem rot (Sclerotinia stem rot). Sclerotinia sclerotia This disease can infect the stems, leaves, flowers, and pods of rapeseed, with the stems being the most severely affected. After infection, water-soaked, light brown lesions appear on the rapeseed stems. Later, the center of the lesions turns white with brown edges, and the boundary between diseased and healthy tissue is clear. In humid conditions, white, cottony mycelium grows on the lesions, eventually leading to stem rot, breakage, and the death of the entire plant, resulting in total crop failure. Currently, there is a severe shortage of pesticides for controlling rapeseed sclerotinia rot. Most pesticides are concentrated on carbendazim, iprodione, and fludioxonil. However, resistance to carbendazim has become severe. According to a 2024 monitoring report from the National Agricultural Technology Extension Center, strains isolated from rapeseed samples collected from 23 counties (cities, districts) in 8 provinces (municipalities) showed significant resistance to carbendazim, with the frequency of resistant strains exceeding 98% in Hunan, Jiangsu, Jiangxi, Anhui, and Zhejiang provinces. There is an urgent need for new pesticide varieties to control this disease, replace carbendazim, and control the development of resistance.

[0007] Triazole fungicides are currently the most widely used and diverse class of fungicides in agriculture. Their mechanism of action involves inhibiting the CYP51 enzyme (sterol 14α-demethylase) within pathogens, blocking ergosterol biosynthesis, and disrupting the structure and function of fungal cell membranes, thus possessing protective, curative, and eradicative effects. Triazole fungicides have a broad fungicidal spectrum, high activity, and excellent systemic activity, and are widely used for the control of powdery mildew, rust, sclerotinia rot, sheath blight, leaf spot, and root rot in cereals, fruits, vegetables, and cash crops. The main varieties in this class include triadimefon, triazole alcohol, tebuconazole, difenoconazole, propiconazole, and flutriafol. Difenoconazole is a representative variety. However, triazole fungicides have a single target, and long-term use in isolation carries the risk of inducing resistance. In addition, some triazole pesticides can affect the synthesis of gibberellin (GA) in crops and interfere with abscisic acid (ABA) metabolism, thus having a regulatory effect on crop growth. Therefore, controlling the dosage of these pesticides to avoid phytotoxicity is also a challenge in the current promotion and use of pesticides.

[0008] Currently, there are few pesticide options available for controlling rice bakanae disease, wheat stem rot, wheat scab, plant root rot, and rapeseed sclerotinia stem rot. Furthermore, the long-term and extensive use of selective pesticides with single mechanisms of action has led to varying degrees of pesticide resistance in pathogens. Developing fungicides with novel mechanisms of action and introducing them to the market, along with scientifically formulated combinations of these novel agents with broad-spectrum, highly effective triazole fungicides, can reduce pesticide dosage, improve efficacy, and delay the development of resistance. This is of great significance for controlling disease occurrence and extending the lifespan of pesticides. Summary of the Invention

[0009] The purpose of this invention is to provide a fungicidal composition containing WML-01 and triazole compounds, its formulation and application, to solve the technical problems that currently exist, such as the limited variety of fungicides for the control of rice seedling blight, wheat stem base rot, wheat scab, plant root rot and rapeseed sclerotinia, and the fact that pathogens have developed varying degrees of resistance due to the long-term and large-scale use of selective agents with single mechanisms of action.

[0010] To achieve the objectives of this invention, a first aspect of this invention is to provide a bactericidal composition containing WML-01 and a triazole compound, said bactericidal composition comprising WML-01 and difenoconazole, wherein the mass ratio of WML-01 to difenoconazole is 10:1 to 1:10; wherein WML-01 is a butenolactone compound containing a thiazolidinone structure, and its structural formula is shown in formula (I):

[0011] .

[0012] In one optional embodiment, the mass ratio of WML-01 to difenoconazole is 1:1 to 1:10.

[0013] In one optional embodiment, the mass ratio of WML-01 to difenoconazole is 10:1 to 2:1.

[0014] A second aspect of the present invention is to provide a bactericidal preparation comprising the bactericidal composition.

[0015] In one optional embodiment, the bactericidal formulation is a seed coating agent, suspension, emulsion, microemulsion, emulsifiable concentrate, microcapsule suspension, nanoformulation, granules, wettable powder, or water-dispersible granules.

[0016] A third aspect of the present invention is to provide the application of a fungicidal composition or fungicide in the control of plant diseases, wherein the plant disease is rice bakanae disease. Fusarium fujikuroi , Wheat stem rot Fusarium pseudograsses wheat scab Fusarium gramineae , soybean root rot Fusarium spp .、 Anthracnose of peppers Colletotrichum spp . Or rapeseed sclerotinia stem rot Sclerotinia sclerotiorum One or more of them.

[0017] In one optional embodiment, the bactericidal preparation further includes an adjuvant or carrier that assists the bactericidal composition, wherein the adjuvant is xanthan gum, wetting agent, dispersant, defoamer, antifreeze agent or warning color.

[0018] In one optional embodiment, the wetting agent is nonylphenol polyoxyethylene ether NP-10, alkylphenol polyoxyethylene ether OP-10, or alkyl naphthalene sulfonate EFW; the dispersant is sodium salt D-425 of alkyl naphthalene sulfonate condensate or sulfonate D-450 of alkyl naphthalene sulfonate condensate; the defoamer is n-octanol or organosilicon SAG1522; the antifreeze agent is ethylene glycol; and the warning color is basic rose essence, golden red, or sun-resistant peach red.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The fungicidal composition provided by this invention, which uses WML-01 and triazole agents as active ingredients, has a synergistic effect on the control of rice bakanae disease, wheat stem base rot, wheat scab, soybean root rot, and rapeseed sclerotinia stem rot. It can effectively improve the control effect of diseases, reduce the amount of pesticides used, delay the occurrence of pesticide resistance, and increase crop yield. It is safe, effective, and economical, and has broad market application prospects. Detailed Implementation

[0021] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the invention. Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art, and the raw materials used are all commercially available products.

[0022] The application methods of the fungicidal composition and its formulations are diverse, and this invention does not impose any particular limitation. One or a combination of various application methods can be used, such as seed coating, seed soaking, spraying, root drenching, broadcasting, hole application, and furrow application. Depending on the crop cultivation, formulation form, and target pests, seed coating, seed dressing, and seed soaking are preferred methods for this fungicidal composition.

[0023] Example 1: In vitro antibacterial activity of WML-01 and difenoconazole against rice bakanae disease pathogens, wheat stem rot pathogens, wheat scab pathogens, soybean root rot pathogens, pepper anthracnose pathogens, and rapeseed sclerotinia pathogens.

[0024] 1. Test materials

[0025] 1.1 Test strains

[0026] Rice seedling blight pathogen ( F. fujikuroi (Provided by the College of Plant Protection, China Agricultural University), identified using conventional methods.

[0027] Soybean root rot pathogen ( F. oxysporum (Provided by the College of Plant Protection, China Agricultural University), identified using conventional methods.

[0028] Wheat stem rot fungus ( F. pseudograminearum (Provided by the College of Plant Protection, China Agricultural University), identified using conventional methods.

[0029] Fusarium head blight of wheat ( F. grasses (Provided by the College of Plant Protection, China Agricultural University), identified using conventional methods.

[0030] Sclerotinia sclerotiorum (Sclerotinia sclerotiorum) S. sclerotiorum (Provided by the College of Plant Protection, China Agricultural University), identified using conventional methods.

[0031] The anthracnose fungus of pepper (C. gloeosporioides) (provided by the College of Plant Protection, China Agricultural University) was identified using conventional methods.

[0032] 1.2 Test reagents

[0033] WML-01 (99% technical grade), provided by the College of Science, China Agricultural University. This compound and its preparation method are disclosed in patent publication number CN 118724887 A, compound number 3-1.

[0034] Its structural formula is shown in equation (I):

[0035]

[0036] Difenoconazole (95% technical grade), a product of Shandong United Pesticide Industry Co., Ltd.

[0037] The above-mentioned pesticide technical material was prepared into a concentration of 10 using dimethyl sulfoxide as a solvent. 4 The stock solution of mg / L was stored in a refrigerator at 4°C for later use.

[0038] 1.3 Test Culture Medium

[0039] Potato glucose agar (PDA): 200 g potato, 18 g glucose, 12 g agar powder, 1000 mL distilled water.

[0040] 2. Test Methods

[0041] The experiment was conducted according to NY / T 1156.2-2006, "Guidelines for Indoor Bioassay Testing of Pesticides - Part 2: Tests for Inhibition of Mycelial Growth of Pathogenic Fungi," using the plate method. The main procedure for the plate method is as follows: Five concentration gradients were set between 10% and 90% for the inhibition rate of the pesticide against the target bacteria. Then, using a 6mm diameter punch, mycelial cakes were collected from the same circumference near the edge of the activated target bacteria colony (ensuring the same age of the tested pathogens in the same replicate). Under aseptic conditions, the mycelial cakes were inoculated onto the center of a series of drug-containing culture plates, with the mycelial side facing down. A plate without pesticide was used as a control. All plates were incubated in the dark. Each treatment was repeated three times. The colony diameter for each concentration treatment was recorded, and the mycelial growth inhibition rate was calculated. Then, the inhibition rate was converted into a probability value (Y), and the drug concentration was converted into a logarithmic value to base 10 (X). A regression line was plotted between X and Y to obtain the virulence regression curve equation Y=a+bX for each drug against the target bacteria, as well as the correlation coefficient r and the effective inhibition concentration EC. 50 .

[0042] The combined toxicity of compound preparations was expressed using Sun Yunpei's co-toxicity coefficient method:

[0043] Theoretical toxicity index of compound preparations THIRTY =∑(Toxicity index of a certain drug × Percentage of the active ingredient of the drug in the mixture).

[0044]

[0045] CTC At ≥120, it has a synergistic effect; CTC At ≤80, the effect is antagonistic; at <80, the effect is antagonistic. CTC When the value is less than 120, the effect is additive.

[0046] 3. Experimental Results

[0047] Table 1. In vitro antibacterial activity of WML-01 and difenoconazole against *Bakanaeda jatropha*, the pathogen of rice seedling blight.

[0048]

[0049] The above results indicate that the co-toxicity coefficients of WML-01 and difenoconazole in the compound range of 10:1 to 1:10 (w / w) against rice bakanae disease range from 96.14 to 201.01, showing additive and synergistic effects. Among them, when the mass ratio of WML-01 to difenoconazole is in the range of 1:1 to 1:10, the co-toxicity coefficients are all greater than 120, showing a synergistic effect, and the synergistic effect is significant, reaching a maximum of 173.51.

[0050] Table 2. In vitro antibacterial activity of WML-01 and difenoconazole combined against wheat stem rot fungus.

[0051]

[0052] The above results indicate that when WML-01 and difenoconazole are combined at a mass ratio of 10:1 to 1:10 (w / w), the co-toxicity coefficients against wheat stem rot pathogens, determined by the co-toxicity coefficient method, range from 81.34 to 176.65, showing additive and synergistic effects. Among them, when the mass ratio of WML-01 to difenoconazole is in the range of 1:2 to 1:10, the co-toxicity coefficients are all greater than 120, showing a significant synergistic effect, which can reach a maximum of 176.65.

[0053] Table 3. In vitro antibacterial activity of WML-01 and difenoconazole against Fusarium graminearum, the causal agent of wheat blight.

[0054]

[0055] The above results indicate that when WML-01 and difenoconazole are combined at a mass ratio of 10:1 to 1:10 (w / w), the co-toxicity coefficients against Fusarium graminearum, the causal agent of wheat blight, range from 87.11 to 184.28, as determined by the co-toxicity coefficient method. This shows additive and synergistic effects. When the mass ratio of WML-01 to difenoconazole is in the range of 1:2 to 1:10, the co-toxicity coefficients are all greater than 120, demonstrating a significant synergistic effect, which can reach a maximum of 184.28.

[0056] Table 4. In vitro antibacterial activity of WML-01 and difenoconazole against soybean root rot pathogen.

[0057]

[0058] The above results indicate that when WML-01 and difenoconazole are combined at a mass ratio of 10:1 to 1:10 (w / w), the co-toxicity coefficients against soybean root rot pathogens, determined by the co-toxicity coefficient method, range from 83.32 to 176.54, showing additive and synergistic effects. Among them, when the mass ratio of WML-01 to difenoconazole is in the range of 1:1 to 1:10, the co-toxicity coefficients are all greater than 120, showing a significant synergistic effect, which can reach a maximum of 176.54.

[0059] Table 5. In vitro antibacterial activity of WML-01 and difenoconazole against Sclerotinia sclerotinia, the causal agent of rapeseed rot.

[0060]

[0061] The above results indicate that when WML-01 and difenoconazole are combined at a mass ratio of 10:1 to 1:10 (w / w), the co-toxicity coefficients against Sclerotinia sclerotinia in rapeseed, determined by the co-toxicity coefficient method, range from 83.43 to 189.06, showing additive and synergistic effects. Among them, when the mass ratio of WML-01 to difenoconazole is in the range of 10:1 to 2:1, the co-toxicity coefficients are all greater than 120, showing a significant synergistic effect, which can reach a maximum of 189.06.

[0062] Table 6. In vitro antibacterial activity of WML-01 and difenoconazole against *Anthracis capsulatum*.

[0063]

[0064] The above results indicate that when WML-01 and difenoconazole are combined at a mass ratio of 10:1 to 1:10 (w / w), the co-toxicity coefficients against *Anthracnose causal agent* of pepper are between 83.03 and 112.17, as determined by the co-toxicity coefficient method. This shows an additive effect with no antagonistic effect.

[0065] Example 2: Field control efficacy of WML-01 and difenoconazole combination against wheat scab.

[0066] 1. Materials and Methods

[0067] 1.1 Test Materials

[0068] 15% WML-01·difenoconazole suspension, self-made, comprising 5% WML-01, 10% difenoconazole, 3% MorwetD-425, 1% Witconol NP-100, 0.3% xanthan gum, and water balance, % is by mass percentage, prepared by sand milling process; 10% WML-01 suspension, self-made, comprising 10% WML-01, 3% MorwetD-425, 1% Witconol NP-100, 0.3% xanthan gum, and water balance, % is by mass percentage, prepared by sand milling process; 40% difenoconazole suspension, product of Qingdao Audis Biotechnology Co., Ltd., Shandong Province.

[0069] 1.2 Overview of the test site

[0070] The experiment was conducted in Fengtai County, Anhui Province, in a clay loam soil with moderate fertility. The wheat variety was Huaiyumai No. 1, and the seed rate was 25 kg per mu.

[0071] 1.3 Experimental Design

[0072] Table 7. Experimental protocols for seed treatment against wheat scab.

[0073]

[0074] 1.4 Survey Methods and Calculations

[0075] Five random sampling points were taken from each treatment area, with 100 ears of panicle at each point. The disease index and control effect were calculated based on the percentage of panicle dead area to the total panicle area.

[0076] Grading standards for Fusarium head blight:

[0077] Grade 0, disease-free throughout the ear of grain;

[0078] Grade 1: The area of ​​dead ears accounts for less than 1 / 4 of the total ear area;

[0079] Grade 3, with withered ears covering 1 / 4 to 1 / 2 of the total ear area;

[0080] Grade 5, withered ears covering 1 / 2 to 3 / 4 of the total ear area;

[0081] Grade 7, with withered ears covering more than 3 / 4 of the total ear area;

[0082] Methods for calculating drug efficacy:

[0083] Disease index (%) = ∑(Number of diseased plants (ears) at each level × Representative value at each level) / (Total number of plants (ears) surveyed × Highest representative value) × 100

[0084] Control efficacy (%) = (Disease index after treatment in control area - Disease index after treatment in treatment area) / Disease index after treatment in control area × 100

[0085] 2. Experimental Results

[0086] Table 8. Control efficacy of pesticide treatments against wheat scab.

[0087]

[0088] Note: * The average of 4 repetitions; ** The significance level for the analysis of variance was p = 0.05.

[0089] As shown in the table above, after two applications, the high-dose (200 ml) treatment of 15% WML-01·difenoconazole suspension (30 g active ingredient) achieved a control efficacy of 89.46% against wheat scab, significantly better than the single-dose treatment of difenoconazole (16 g active ingredient) and the single-dose treatment of WML-01 (20 g active ingredient). The low-dose (100 ml) treatment (15 g active ingredient) achieved a control efficacy of 85.54% against wheat scab, also better than the single-dose treatments of WML-01 and difenoconazole.

[0090] The above results indicate that the combination of WML-01 and difenoconazole exhibits excellent control efficacy against wheat scab at a dosage similar to that of difenoconazole alone. Compared with WML-01 alone, the field application amount is reduced while the control efficacy remains good.

[0091] Example 3: Field control efficacy of WML-01 and difenoconazole combined with soybean root rot

[0092] 1. Materials and Methods

[0093] 1.1 Test Materials

[0094] 15% WML-01·difenoconazole suspension concentrate, self-made, comprising 5% WML-01, 10% difenoconazole, 3% MorwetD-425, 1% Witconol NP-100, 0.3% xanthan gum, and water balance, % is by mass percentage, prepared by sand milling process; 10% WML-01 suspension concentrate, self-made, comprising 10% WML-01, 3% MorwetD-425, 1% Witconol NP-100, 0.3% xanthan gum, and water balance, % is by mass percentage, prepared by sand milling process; 3% difenoconazole suspension concentrate, produced by Shandong United Pesticide Industry Co., Ltd.

[0095] 1.2 Overview of the test site

[0096] The experimental site was located in the Beian Modern Agricultural Demonstration Park. The soil type was black soil, with an organic matter content of 5.6% and a pH of 6.6. Sowing was carried out on May 21, 2024, using a 65cm ridge-three cultivation pattern, maintaining 320,000 plants per hectare. 48% soybean-specific fertilizer was applied at a rate of 320 kg per hectare (N:P:K = 15:23:10). Emergence occurred on June 1. Soil moisture was good. The previous crop was soybean. Irrigation relied on natural rainfall.

[0097] 1.3 Experimental Design

[0098] Table 9 Experimental protocols for seed treatment on plant root rot

[0099]

[0100] 1.4 Survey Methods and Calculations

[0101] Soybean root rot survey

[0102] Surveys were conducted twice, at 30 days and 60 days after soybean emergence. At least 30 soybean plants were randomly selected from each plot for investigation, and the total number of plants and the number of plants with diseases at each level were recorded. The incidence of root rot was investigated, and the effectiveness of control measures was calculated.

[0103] Disease classification: (area of ​​lesions on the roots)

[0104] Grade 0: Main root and fibrous roots are intact, with no disease spots and many root nodules;

[0105] Grade 1: Scattered lesions on the main root, but not in clusters; lesions on the fibrous roots for several days.

[0106] Grade 3: The main root shows numerous lesions, but the lesions cover less than 1 / 4 of the root area; the fibrous roots are slightly affected.

[0107] Grade 5: The lesions on the main root cover an area of ​​1 / 4 to 1 / 2 of the root area. There are many fibrous roots affected, but they do not form large patches.

[0108] Grade 7: The area of ​​lesions on the main root is between 1 / 2 and 1 / 4 of the root area, and the lesions on the fibrous roots are in patches, with some fibrous roots falling off;

[0109] Level 9: The entire root system is surrounded by disease spots, the root is rotten, and there are almost no fibrous roots.

[0110] Methods for calculating drug efficacy:

[0111] Disease index (%) = ∑(Number of diseased plants (ears) at each level × Representative value at each level) / (Total number of plants (ears) surveyed × Highest representative value) × 100

[0112] Control efficacy (%) = (Disease index after treatment in control area - Disease index after treatment in treatment area) / Disease index after treatment in control area × 100

[0113] 2. Experimental Results

[0114] Table 10. Control efficacy of chemical treatments against soybean root rot

[0115]

[0116] Note: * The average of 4 repetitions; ** The significance level for the analysis of variance was p = 0.05.

[0117] The table above shows that, 30 days after emergence, the high-dose (200 ml) seed dressing treatment of 15% WML-01·difenoconazole suspension (30 g active ingredient) showed a control efficacy of 87.52% against soybean root rot, significantly better than WML-01 (20 g active ingredient) and difenoconazole (12 g active ingredient) alone. The low-dose (100 ml) treatment of 15% WML-01·difenoconazole suspension (15 g active ingredient) showed a control efficacy of 80.94% against soybean root rot, significantly better than difenoconazole and WML-01 alone.

[0118] A survey conducted 60 days after sowing showed that seed treatments with 100 ml and 200 ml of 15% WML-01·difenoconazole suspension exhibited excellent control efficacy against soybean root rot, with rates of 87.90% and 93.30%, respectively, significantly superior to single treatments with WML-01 and difenoconazole.

[0119] The above results indicate that the combination of WML-01 and difenoconazole, at a similar dosage to difenoconazole alone, exhibits excellent control efficacy against soybean root rot. Compared to the single-agent treatment with WML-01, the field application dosage is reduced while the control efficacy is improved.

[0120] Example 4: Field control efficacy of WML-01 and difenoconazole combination against wheat stem rot

[0121] 1. Materials and Methods

[0122] 1.1 Test Materials

[0123] 15% WML-01·difenoconazole suspension concentrate, self-made, comprising 5% WML-01, 10% difenoconazole, 3% MorwetD-425, 1% Witconol NP-100, 0.3% xanthan gum, and water balance, % is by mass percentage, prepared by sand milling process; 10% WML-01 suspension concentrate, self-made, comprising 10% WML-01, 3% MorwetD-425, 1% Witconol NP-100, 0.3% xanthan gum, and water balance, % is by mass percentage, prepared by sand milling process; 3% difenoconazole suspension concentrate, produced by Shandong United Pesticide Industry Co., Ltd.

[0124] 1.2 Overview of the test site

[0125] The experiment was conducted in Feixiang District, Handan City, Hebei Province. The soil was clay loam with moderate fertility. The wheat variety was Woyu No. 3, and the seed rate was 20 kg per mu.

[0126] 1.3 Experimental Design

[0127] Table 11 Experimental protocol for seed treatment against wheat stem rot

[0128]

[0129] 1.4 Survey Methods and Calculations

[0130] Stem base rot survey

[0131] a) Survey on the efficacy of stem base rot control during the grain-filling stage

[0132] Five random sampling points were taken from each treatment area, with 100 plants at each point. The number of diseased plants and the disease index were investigated, and the disease index and control effect were calculated.

[0133] Grading standards for stem base rot:

[0134] Grade 0, the plant is not diseased;

[0135] Grade 1, the stem in the ground is noticeably brown;

[0136] Level 3, the first intersegment turns brown;

[0137] Level 5, second interphalangeal joint turns brown;

[0138] Level 7, browning symptoms appear in the third internode, but no white ears;

[0139] Level 9: White ears or plant death due to disease.

[0140] Methods for calculating drug efficacy:

[0141] Disease index (%) = ∑(Number of diseased plants (ears) at each level × Representative value at each level) / (Total number of plants (ears) surveyed × Highest representative value) × 100

[0142] Control efficacy (%) = (Disease index after treatment in control area - Disease index after treatment in treatment area) / Disease index after treatment in control area × 100

[0143] b) Survey of white ear rate during the grain-filling stage

[0144] Five random sampling points were taken from each treatment area, with 100 plants at each point. The total number of ears and the number of white ears were investigated, and the control effect was calculated.

[0145] White ear rate (%) = Number of white ears / Total number of plants surveyed × 100

[0146] Control efficacy (%) = [White ear rate in control area - White ear rate in treated area] / White ear rate in control area × 100

[0147] 2. Experimental Results

[0148] Table 12. Control efficacy of pesticide treatments against wheat stem rot.

[0149]

[0150] Note: * The average of 4 repetitions; ** The significance level for the analysis of variance was p = 0.05.

[0151] The table above shows that, during the grain-filling stage, a high-dose (200 ml) seed treatment with 15% WML-01·difenoconazole suspension (30 g active ingredient) achieved an efficacy of 84.69% against wheat stem rot, significantly better than the difenoconazole single-agent treatment (12 g active ingredient). A low-dose (100 ml) treatment (15 g active ingredient) achieved an efficacy of 83.70% against wheat stem rot, significantly better than the difenoconazole single-agent seed treatment and slightly better than the WML-01 single-agent treatment (20 g active ingredient).

[0152] The results of the white ear rate survey showed that the high-dose treatment of 15% WML-01·difenoconazole suspension (200 ml) achieved a white ear control efficacy of 93.96%; the low-dose treatment (100 ml) achieved a white ear control efficacy of 87.77%, which was significantly better than the single-agent treatment of WML-01 and the single-agent treatment of difenoconazole.

[0153] The above results indicate that the combination of WML-01 and difenoconazole, at a similar dosage to difenoconazole alone, exhibits excellent control efficacy against wheat stem rot. Compared to the single-dose treatment with WML-01, the field application dosage is reduced while the control efficacy is improved.

[0154] Example 5: Field control efficacy of WML-01 and difenoconazole combined with rice bakanae disease

[0155] 1. Materials and Methods

[0156] 1.1 Test Materials

[0157] 15% WML-01·difenoconazole suspension concentrate, self-made, comprising 5% WML-01, 10% difenoconazole, 3% MorwetD-425, 1% Witconol NP-100, 0.3% xanthan gum, and water balance, % is by mass percentage, prepared by sand milling process; 10% WML-01 suspension concentrate, self-made, comprising 10% WML-01, 3% MorwetD-425, 1% Witconol NP-100, 0.3% xanthan gum, and water balance, % is by mass percentage, prepared by sand milling process; 3% difenoconazole suspension concentrate, produced by Shandong United Pesticide Industry Co., Ltd.

[0158] 1.2 Overview of the test site

[0159] The experiment was conducted in Zhaoyuan Village, Yaojiang Town, Zhuji City, Zhejiang Province. The soil was clay loam with moderate fertility. The rice variety was Zhongzao 39, and the seed rate was 5 kg per mu. Seedlings were raised and transplanted.

[0160] 1.3 Experimental Design

[0161] Table 13 Experimental protocol for seed treatment against rice bakanae disease

[0162]

[0163] 1.4 Survey Methods and Calculations

[0164] Bakanae disease: Five random sampling points were taken from each plot in the seedbed, with each sampling point measuring 10cm*10cm. The sampling was repeated three times. The disease incidence rate was recorded, and the control efficacy was calculated.

[0165] Disease incidence rate (%) = (Number of diseased plants / Total number of plants surveyed) × 100%

[0166] Control efficacy (%) = (Disease rate in the blank control area - Disease rate in the treatment area) / Disease rate in the blank control area × 100%

[0167] 2. Experimental Results

[0168] Table 14. Control efficacy of pesticide treatments against rice bakanae disease

[0169]

[0170] Note: * The average of 4 repetitions; ** The significance level for the analysis of variance was p = 0.05.

[0171] As shown in the table above, during the seedling stage, a high-dose seed treatment of 200 ml of 15% WML-01·difenoconazole suspension (30 g of active ingredient) achieved a 97.97% control efficacy against rice bakanae disease; a seed treatment of 100 ml (15 g of active ingredient) achieved a 95.44% control efficacy against rice bakanae disease, which was significantly better than the single treatment of difenoconazole (15 g) and the single treatment of WML-01 (20 g of active ingredient).

[0172] The above results indicate that when WML-01 and difenoconazole are combined, they exhibit excellent control efficacy against bakanae disease at the same dosage as difenoconazole alone. Compared with WML-01 alone, the field application amount is significantly reduced while the control efficacy is still good.

[0173] Example 6: Field control efficacy of WML-01 and difenoconazole combined with rapeseed sclerotinia stem rot

[0174] 1. Materials and Methods

[0175] 1.1 Test Materials

[0176] 15% WML-01·difenoconazole suspension, self-made, comprising 10% WML-01, 5% difenoconazole, 3% MorwetD-425, 1% Witconol NP-100, 0.3% xanthan gum, and water balance, % is by mass percentage, prepared by sand milling process; 10% WML-01 suspension, self-made, comprising 10% WML-01, 3% MorwetD-425, 1% Witconol NP-100, 0.3% xanthan gum, and water balance, % is by mass percentage, prepared by sand milling process; 40% difenoconazole suspension, product of Qingdao Audis Biotechnology Co., Ltd., Shandong Province.

[0177] 1.2 Overview of the test site

[0178] The experiment was conducted in Dafasi Town, Wuxue City, Huanggang City, Hubei Province, in a loamy soil.

[0179] The rapeseed variety Huayouza 62 was sown at a rate of 400g / mu.

[0180] 1.3 Experimental Design

[0181] Table 15 Experimental Protocol for Chemical Treatment of Sclerotinia stem Cellar Disease in Rapeseed

[0182]

[0183] 1.4 Survey Methods and Calculations

[0184] A five-point sampling method was used, with at least 40 plants sampled at each point, and 200 plants surveyed per plot. The number of diseased plants and the disease severity were recorded for each plot. The disease index and control effect were calculated.

[0185] The grading criteria are as follows:

[0186] Level 0: No disease;

[0187] Grade 1: The affected area accounts for less than 5% of the surface area of ​​the main stem;

[0188] Level 3: The affected area accounts for more than 5% but less than 15% of the main stem surface area;

[0189] Level 5: The affected area accounts for more than 15% but less than 30% of the main stem surface area;

[0190] Level 7: The affected area accounts for more than 30% but less than 50% of the main stem surface area;

[0191] Level 9: The diseased area accounts for more than 50% of the surface area of ​​the main stem.

[0192] Methods for calculating drug efficacy:

[0193] Disease index (%) = ∑(Number of diseased plants at each level × Representative value at each level) / (Total number of plants surveyed × Highest representative value) × 100

[0194] Control efficacy (%) = (Disease index after treatment in control area - Disease index after treatment in treatment area) / Disease index after treatment in control area × 100

[0195] 2. Experimental Results

[0196] Table 16. Efficacy of pesticide treatment in controlling sclerotinia stem rot in rapeseed.

[0197]

[0198] Note: * The average of 4 repetitions; ** The significance level for the analysis of variance was p = 0.05.

[0199] As can be seen from the table above, after two applications, the high-dose 100ml treatment (15 g active ingredient) and the low-dose 50ml treatment (7.5 g active ingredient) of 15% WML-01·difenoconazole suspension showed control efficacy of 89.96% and 82.76% against Sclerotinia sclerotinia in rapeseed, respectively, which were significantly better than the single-agent treatment of difenoconazole (12 g active ingredient) and the single-agent treatment of WML-01 (20 g active ingredient).

[0200] The above results indicate that the combination of WML-01 and difenoconazole exhibits excellent control efficacy against sclerotinia stem rot in rapeseed, and significantly reduces the amount of pesticide used in the field.

[0201] Example 8: Field control efficacy of WML-01 and difenoconazole combined with pepper anthracnose.

[0202] 1. Materials and Methods

[0203] 1.1 Test Materials

[0204] 15% WML-01·difenoconazole suspension, self-made, comprising 5% WML-01, 10% difenoconazole, 3% MorwetD-425, 1% Witconol NP-100, 0.3% xanthan gum, and water balance, % is by mass percentage, prepared by sand milling process; 10% WML-01 suspension, self-made, comprising 10% WML-01, 3% MorwetD-425, 1% Witconol NP-100, 0.3% xanthan gum, and water balance, % is by mass percentage, prepared by sand milling process; 40% difenoconazole suspension, product of Qingdao Audis Biotechnology Co., Ltd., Shandong Province.

[0205] 1.2 Overview of the test site

[0206] The experiment was conducted in Daxin Town, Fugou County, Zhoukou City, Henan Province, in loam soil, using the chili pepper variety Mibao 19.

[0207] 1.3 Experimental Design

[0208] Table 17 Experimental Protocol for Chemical Treatments Against Anthracnose in Peppers

[0209]

[0210] 1.4 Survey Methods and Calculations

[0211] Five samples were taken from each area, and 20 fruits were investigated at each point. The fruits were graded based on the percentage of diseased area to the total fruit area.

[0212] Grading method:

[0213] Grade 0: No lesions;

[0214] Grade 1: The area of ​​lesions is less than 5% of the total fruit area;

[0215] Grade 3: The area of ​​lesions accounts for more than 5% but less than 10% of the total fruit area;

[0216] Grade 5: The area of ​​lesions accounts for more than 10% but less than 25% of the total fruit area;

[0217] Grade 7: The area of ​​lesions accounts for more than 25% but less than 50% of the total fruit area;

[0218] Level 9: The area of ​​lesions accounts for more than 50% of the total fruit area, or the fruit falls off.

[0219] Methods for calculating drug efficacy:

[0220] Disease index (%) = ∑(Number of diseased fruits at each level × Representative value at each level) / (Total number of fruits surveyed × Highest representative value) × 100

[0221] Control efficacy (%) = (Disease index after treatment in control area - Disease index after treatment in treatment area) / Disease index after treatment in control area × 100

[0222] 2. Experimental Results

[0223] Table 18. Control efficacy of chemical treatments against anthracnose in peppers.

[0224]

[0225] Note: * The average of 4 repetitions; ** The significance level for the analysis of variance was p = 0.05.

[0226] As shown in the table above, after two applications, the high-dose 100ml treatment (15 g active ingredient) of 15% WML-01·difenoconazole suspension showed a control efficacy of 88.04% against anthracnose in peppers, which was significantly better than the single treatment of difenoconazole (16 g active ingredient) and the single treatment of WML-01 (20 g active ingredient). The low-dose 50ml treatment (7.5 g active ingredient) showed a control efficacy of 79.26%, which was comparable to the control efficacy of the single treatment of difenoconazole and the single treatment of WML-01.

[0227] The above results indicate that when WML-01 and difenoconazole are combined, they exhibit excellent control efficacy against pepper anthracnose at the same dosage as the two single agents. When the control efficacy against pepper anthracnose is comparable to that of the two single agents, the amount of pesticide used in the field is reduced.

[0228] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A bactericidal composition containing WML-01 and a triazole compound, characterized in that, The bactericidal composition comprises WML-01 and difenoconazole, wherein the mass ratio of WML-01 to difenoconazole is 5:1 to 1:10; and WML-01 is the compound shown in formula (I): 。 2. The bactericidal composition containing WML-01 and triazole compounds according to claim 1, characterized in that, The mass ratio of WML-01 to difenoconazole is 1:1 to 1:

10.

3. A bactericidal agent, characterized in that, The bactericidal agent comprises the bactericidal composition according to claim 1 or 2.

4. The bactericidal agent according to claim 3, characterized in that, The bactericidal formulation is available in the form of seed coating agent, suspension, emulsion, microemulsion, emulsifiable concentrate, microcapsule suspension, nanoformulation, granules, wettable powder, or water-dispersible granules.

5. The application of the fungicidal composition containing WML-01 and triazole compounds according to any one of claims 1-2 or the fungicidal agent according to any one of claims 3-4 in the control of plant diseases, wherein the plant disease is caused by Fusarium oxysporum. Fusarium fujikuroi The rice seedling blight caused by WML-01, wherein the mass ratio of WML-01 to difenoconazole in the fungicide composition containing WML-01 and triazole compounds or the fungicide preparation is 1:1 to 1:10; Or the plant disease is caused by Fusarium pseudograss. Fusarium pseudograminearum The wheat stem base rot caused by WML-01, wherein the mass ratio of WML-01 to difenoconazole in the fungicide composition containing WML-01 and triazole compounds or the fungicide preparation is 1:2 to 1:10; Or the plant disease is caused by Fusarium graminearum. Fusarium graminearum The fungicide containing WML-01 and triazole compounds, or the fungicide preparation containing WML-01 and difenoconazole, has a mass ratio of WML-01 to difenoconazole of 1:2 to 1:

10. Or the plant disease is caused by Fusarium oxysporum. Fusarium oxysporum The soybean root rot caused by WML-01, wherein the mass ratio of WML-01 to difenoconazole in the fungicide composition containing WML-01 and triazole compounds or the fungicide preparation is 1:1 to 1:10; Or the plant disease is caused by Sclerotinia sclerotiorum. Sclerotinia sclerotiorum The fungicide containing WML-01 and triazole compounds, or the fungicide preparation containing WML-01 and difenoconazole, has a mass ratio of WML-01 to difenoconazole of 5:1 to 2:1.

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