A compound of fluoroquinacil and pyraclostrobin, a fungicide and application thereof

Abstract

The application discloses a fluoroquinconazole and pyraclostrobin compound composition, a fungicide and application thereof in the field of fungicides, the compound composition is composed of two active ingredients of fluoroquinconazole and pyraclostrobin, and the mass ratio of the fluoroquinconazole to the pyraclostrobin is 40:1-1:40, the fungicide contains the compound composition, and carriers and auxiliaries, and the fungicide can be applied in the prevention and treatment of crop fungal diseases, such as common rice sheath blight, rice blast, wheat powdery mildew or wheat scab. The fluoroquinconazole and the pyraclostrobin are compounded in a specific ratio for the first time, a significant synergistic effect is exhibited, when applied in the field, the prevention and treatment effect is ensured, pesticide input cost and environmental release amount are significantly reduced, pesticide residues in agricultural products are reduced, the number of pesticide application times is reduced, and labor cost is saved.

Description

Technical Field

[0001] This invention relates to the field of fungicide technology, specifically to a compound composition of fluquinacrine and pyraclostrobin, a fungicide, and its application. Background Technology

[0002] Rice sheath blight (Rhizoctonia solani), rice blast (Magnaporthe oryzae), wheat powdery mildew (Blumeria graminis), and wheat scab (Fusarium graminearum) are major diseases affecting staple food crops. For a long time, chemical control has remained the primary means of controlling these diseases. However, with the long-term and extensive use of single fungicides, the problem of pathogen resistance in the field has become increasingly prominent. For example, rice blast fungus has developed varying degrees of resistance to fungicides such as isoprothiolane and wheat scab fungus to carbendazim, leading to decreased control efficacy, increased pesticide costs, and a heightened risk of pesticide residue exceeding limits. Therefore, it is necessary to develop new compound fungicide products to achieve the goals of reducing dosage while increasing efficacy and delaying the development of resistance.

[0003] Fluquinometoate is a novel quinolone fungicide for agricultural use. Its chemical name is 7-chloro-1-cyclopropyl-6-fluoro-4-oxoylide-1,4-dihydroquinoline-3-(2-methoxyethyl)carbamate, and its molecular formula is C2. 16 H 15 ClFNO4 has a relative molecular mass of 339.746 and a CAS Registry Number of 2408468-30-2. The chemical structure of fluoroquinolones is similar to that of quinolone antibacterial drugs in the pharmaceutical field. Its mechanism of action is presumed to target bacterial DNA gyrase and topoisomerase IV, exerting its bactericidal effect by inhibiting DNA replication, transcription, transport, and recombination.

[0004] Pyraclostrobin is a methoxyacrylate fungicide with the chemical name N-[2-[[1-(4-chlorophenyl)pyrazol-3-yl]oxymethyl]phenyl]-N-methoxycarbamate and the molecular formula C2. 19 H 18 ClN3O4, with a relative molecular mass of 387.817 and CAS Registry Number 175013-18-0, is a fungicide. Its mechanism of action is as a mitochondrial respiration inhibitor. It binds to the Qo site of cytochrome b in cytochrome bc1 complex III, preventing electron transport and thus preventing mitochondria from producing the energy (ATP) needed for cellular metabolism, ultimately leading to fungal cell death. Pyraclostrobin exhibits protective, curative, and leaf-penetrating translocation effects, demonstrating good inhibitory activity against various pathogenic fungi, including those belonging to the Ascomycetes, Basidiomycetes, Deuteromycetes, and Oomycetes classes.

[0005] Fluquinazon targets key enzymes in bacterial DNA replication, while pyraclostrobin acts on electron transport in the fungal mitochondrial respiratory chain. Their mechanisms of action are completely different, and their target sites do not overlap, theoretically suggesting a potential for synergistic effects when combined. However, there are currently no reports on the combination of fluquinazon and pyraclostrobin. Because their mechanisms of action belong to different categories, whether a combination will produce a synergistic effect, or exhibit additive or even antagonistic effects, cannot be predicted through theoretical deduction and requires verification through systematic indoor toxicity assays and field efficacy trials. Summary of the Invention

[0006] The purpose of this invention is to provide a compound composition of fluquinacrine and pyraclostrobin, a fungicide and its application, which overcomes the disadvantages of fluquinacrine and pyraclostrobin when used as single agents in terms of pesticide application rate and pathogen resistance.

[0007] The present invention achieves the above objectives through the following technical solutions: A compound composition of quinclorac and pyraclostrobin, wherein the compound composition consists of two active ingredients, quinclorac and pyraclostrobin, and the mass ratio of quinclorac to pyraclostrobin is 40:1 to 1:40.

[0008] A further improvement is that the mass ratio of fluquinacrine to pyraclostrobin is 5:1 to 1:5.

[0009] A further improvement is that the mass ratio of fluquinacrine to pyraclostrobin is 5:1, 2:1, 1:1, 1:2, or 1:5.

[0010] The present invention also provides a fungicide comprising the aforementioned compound composition, as well as a pesticide-acceptable carrier and adjuvants.

[0011] A further improvement is that the compound composition has a mass percentage of 25-50% in the bactericide.

[0012] A further improvement is that the formulation of the bactericide is any one of the following: suspension concentrate, dispersible oil suspension concentrate, water-dispersible granules, wettable powder, water emulsion, microemulsion, emulsifiable concentrate, microcapsule suspension concentrate, or suspension emulsion.

[0013] For example, when the fungicide is a suspension, it may contain: fluquinacrid, pyraclostrobin, dispersant, wetting agent, antifreeze agent, thickener, preservative, defoamer, and water. Fluquinacrid and pyraclostrobin technical materials are mixed with dispersant, wetting agent, antifreeze agent, some water, and other adjuvants. After high-speed shear pre-dispersion, the mixture is transferred to a sand mill for circulating wet grinding until the target particle size D90 ≤ 5 μm is reached. Then, thickener, preservative, and remaining water are added, and after homogenization and filtration, the suspension is obtained.

[0014] When the fungicide is in the form of water-dispersible granules, it may contain: fluquinacrid, pyraclostrobin, dispersant, wetting agent, disintegrant, and filler. Fluquinacrid or pyraclostrobin technical grade is mixed evenly with adjuvants such as dispersant, wetting agent, disintegrant, and filler, then pulverized to the target fineness using air jet milling or ultrafine milling. An appropriate amount of water is added and kneaded, followed by extrusion granulation or fluidized bed granulation, drying, and sieving to obtain the water-dispersible granules.

[0015] When the fungicide is a dispersible oil suspension, it may contain: fluquinacridone, pyraclostrobin, emulsifier, dispersant, thickener, and dispersion medium. Fluquinacridone and pyraclostrobin technical materials are mixed with emulsifier, dispersant, thickener, and part of the dispersion medium. After high-speed shear pre-dispersion, the mixture is transferred to a sand mill for circulating grinding until the target particle size D90 ≤ 5 μm is reached. The remaining dispersion medium is then added to adjust to the target content. After homogenization, the dispersible oil suspension is obtained.

[0016] In addition, the carriers and adjuvants used can be selected according to the dosage form requirements, for example: The dispersant is selected from one or more of the following: polycarboxylate (such as Tersperse® 2700, Atlox® 4913), lignin sulfonate (such as sodium lignin sulfonate, calcium lignin sulfonate), naphthalene sulfonate formaldehyde condensate (such as NNO, Morwet D-425), sodium methylene bisnaphthalene sulfonate (such as dispersant MF), tristyrylphenol polyoxyethylene ether phosphate, and alkylphenol polyoxyethylene ether phosphate; The wetting agent is selected from one or more of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, fatty alcohol polyoxyethylene ether (such as AEO-3, AEO-5), alkylphenol polyoxyethylene ether (such as OP-10), pull-out powder BX, and sodium dioctyl sulfosuccinate. The emulsifier is selected from one or more of the following: calcium dodecylbenzene sulfonate, castor oil polyoxyethylene ether (EL series), tristyrene phenol polyoxyethylene ether (such as agricultural emulsion 600#), tristyrene phenol polyoxyethylene polyoxypropylene ether block copolymer (such as agricultural emulsion 1601#, agricultural emulsion 1602#), styrene phenol polyoxyethylene ether (such as agricultural emulsion 602#), alkylphenol formaldehyde resin polyoxyethylene ether (such as agricultural emulsion 700#), sorbitan fatty acid ester polyoxyethylene ether (such as Tween series), and fatty alcohol polyoxyethylene ether. The solvent is selected from one or more of the following: aromatic solvent oil (S-100, S-150, S-200), N,N-dimethylformamide, N-methylpyrrolidone, cyclohexanone, acetophenone, sec-butyl acetate, methyl oleate, soybean oil, and dimethyl sulfoxide; The thickener is selected from one or more of xanthan gum, magnesium aluminum silicate, organobentonite, silica, and polyvinyl alcohol; The antifreeze is selected from one or more of ethylene glycol, propylene glycol, glycerol, sorbitol, and urea; The preservative is selected from one or more of sodium benzoate, potassium sorbate, Kathon, and BIT (1,2-benzisothiazolin-3-one); The defoamer is selected from one or more of silicone defoamers (such as polydimethylsiloxane) and polyether defoamers; The disintegrant is selected from one or more of ammonium sulfate, sodium sulfate, sodium chloride, urea, starch and their derivatives; The solid filler is selected from one or more of the following: kaolin, clay, diatomaceous earth, silica, bentonite, light calcium carbonate, talc, and attapulgite. The dispersion medium is selected from one or more of methyl oleate, soybean oil, corn oil, rapeseed oil, coconut oil, and mineral oil.

[0017] The present invention also provides the application of the fungicide in the prevention and control of fungal diseases in crops.

[0018] A further improvement is that the crop is rice or wheat, and the disease is a fungal disease, including but not limited to: Rice diseases: Rhizoctonia solani, Magnaphalthe oryzae, Ustilaginoidea virens; Wheat diseases: powdery mildew (Blumeria graminis), Fusarium graminearum, rust (Puccinia spp.), leaf blight (Septoria spp.); Other crop diseases include: cucumber powdery mildew (Sphaerotheca fuliginea), tomato early blight (Alternaria solani), grape downy mildew (Plasmopara viticola), and banana leaf spot (Mycosphaerella spp.).

[0019] A further improvement is that the application method of the fungicide is as follows: in the early stage of disease occurrence or the initial stage of disease, the fungicide is diluted with water and sprayed evenly on the crop leaves. The effective ingredient dosage is 150-450 grams / hectare, the application interval is 7-14 days, and the application is 1-3 times.

[0020] The beneficial effects of this invention are as follows: (1) This invention is the first to combine fluquinacrine and pyraclostrobin in a specific ratio. Through a large number of indoor toxicity tests, it was found that in the mass ratio range of 40:1-1:40, the co-toxicity coefficient of the two combined with rice sheath blight fungus, rice blast fungus, wheat powdery mildew fungus and Fusarium head blight fungus all reached more than 120, showing a significant synergistic effect, which is not a simple functional superposition. Especially in the range of 5:1-1:5, the co-toxicity coefficient reached more than 180, and the synergistic effect was particularly prominent.

[0021] (2) The amount of active ingredient in the compound composition of the present invention can be reduced by 30-50% compared with that of single agent in field application. While ensuring the control effect, it significantly reduces the cost of pesticide input and the amount released into the environment, which is conducive to reducing pesticide residues in agricultural products. Furthermore, fluoroquinolones and pyraclostrobin act on two completely different target sites, namely DNA replication and mitochondrial respiratory chain, respectively. There is no cross-resistance between the two. Such compound use is conducive to delaying the generation and evolution of resistance of pathogens to any single agent in the field and extending the commercial life of the product.

[0022] (3) The compound composition of the present invention has both protective and therapeutic effects, and its rapid and sustained effects are significantly better than those of each single agent, which helps to reduce the number of administrations and save labor costs. Detailed Implementation

[0023] The present application will be further described in detail below with reference to specific embodiments. It should be noted that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0024] I. Indoor toxicity testing 1. Test materials Test agents: 97% fluquinacrine technical grade (provided by Yinshan Pesticide Research Institute); 98% pyraclostrobin technical grade (commercially available).

[0025] The tested pathogen strains were: Rhizoctonia solani (rice sheath blight); Magnaphorthe oryzae (rice blast); Blumeria graminis (wheat powdery mildew); and Fusarium graminearum (wheat scab).

[0026] 2. Test Methods The inhibition rate of each pesticide treatment on the mycelial growth of the tested pathogen was determined using the mycelial growth rate method. Fluquinazone and pyraclostrobin technical materials were dissolved in acetone to prepare 10000 mg / L stock solutions. These were then mixed according to the designed compounding ratio and diluted with sterile water to create a series of concentration gradients. Under aseptic conditions, each concentration of pesticide solution was quantitatively added to PDA medium that had been melted and cooled to approximately 50°C. After thorough mixing, the solution was poured into plates to prepare pesticide-containing agar plates. Each concentration treatment was repeated four times. PDA plates without pesticides served as blank controls. Mycelial cakes were cut along the edge of the cultured test strain colonies using a 5 mm diameter punch and inoculated into the center of the pesticide-containing agar plates. The plates were incubated at 25°C. After the control colonies had fully colonized the plates, the diameter of each treatment colony was measured using the cross-sectional method, and the mycelial growth inhibition rate was calculated using the following formula:

[0027] Using the logarithm of drug concentration as the independent variable x and the probability of the corresponding inhibition rate as the dependent variable y, a toxicity regression equation y=a+bx is established, and the EC50 of each single agent and combination is calculated. 50 Value. The co-toxicity coefficient method of Sun Yun-Pei was used to evaluate the synergistic effects of the compound combination. The evaluation criteria are as follows: The co-toxicity coefficient is ≥120, indicating a synergistic effect; 80 ≤ co-toxicity coefficient < 120, indicating an additive effect; The co-toxicity coefficient is <80, indicating an antagonistic effect.

[0028] 3. Test Results Table 1: Combined toxicity of different ratios of fluquinacrine and pyraclostrobin against rice sheath blight pathogen.

[0029] Table 2: Combined toxicity of fluquinacrine and pyraclostrobin at different ratios against rice blast fungus

[0030] Table 3: Combined virulence of fluquinacrine and pyraclostrobin at different ratios against wheat powdery mildew.

[0031] Table 4: Combined toxicity of different ratios of fluquinacrine and pyraclostrobin against Fusarium graminearum, the causal agent of wheat blight.

[0032] As shown in Table 1-4, the indoor toxicity test results indicate that the combination of fluquinacrine and pyraclostrobin in a mass ratio range of 40:1-1:40 exhibited co-toxicity coefficients higher than 120 against four major grain crop pathogens: rice sheath blight, rice blast, wheat powdery mildew, and wheat scab, demonstrating a stable synergistic effect. The synergistic effect was most pronounced in the 5:1-1:5 ratio range centered around 1:1, with co-toxicity coefficients generally exceeding 180, indicating that the two active ingredients had the best synergistic effect within this range.

[0033] II. Formulation Examples All percentages in the following examples are by weight, and the active ingredients and adjuvants used in each example are commercially available products.

[0034] Example 1: 45% Fluquinazon·Pyraclostrobin Suspension Concentrate (SC) Fluquinazon technical grade: 20.0%; Pyraclostrobin technical grade: 25.0%; Polycarboxylate dispersant (Tersperse® 2700): 3.0%; Sodium lignosulfonate: 2.0%; Sodium dodecylbenzenesulfonate: 1.5%; Glycerol: 5.0%; Xanthan gum: 0.15%; Magnesium aluminum silicate: 0.5%; Kathon: 0.3%; Organosilicon defoamer: 0.2%; Deionized water: Top up to 100%.

[0035] Preparation method: Fluoroquinolones technical grade, pyraclostrobin technical grade, dispersant, wetting agent, antifreeze, defoamer, and some water are mixed and pre-dispersed by high-speed shearing for 30 minutes. Then, the mixture is transferred to a horizontal sand mill and wet-milled using zirconia beads as the grinding medium until the particle size D90 ≤ 5 μm. After grinding, xanthan gum, magnesium aluminum silicate, preservative, and remaining water are added, and the mixture is homogenized at high speed for 30 minutes. The mixture is then filtered through a 200-mesh sieve to obtain a 45% fluoroquinolones·pyraclostrobin suspension.

[0036] Quality inspection results: Fluoroquinolones content 19.8%, pyraclostrobin content 25.1%, pH 6.8, suspension rate 98.6%, wet sieve test (75μm sieve) passing rate ≥99%, persistent foaming amount ≤20mL, low temperature stability qualified, heat storage (54℃±2℃, 14d) decomposition rate ≤2.5%, particle size D90=3.85μm.

[0037] Example 2: 30% Fluquinazon·Pyraclostrobin Suspension Concentrate (SC) Fluquinazon technical grade: 15.0%; Pyraclostrobin technical grade: 15.0%; Naphthalenesulfonate formaldehyde condensate (NNO): 4.0%; Tristyrene-phenol polyoxyethylene ether phosphate: 2.0%; Sodium dodecyl sulfate: 1.0%; Glycerol: 4.0%; Xanthan gum: 0.12%; BIT: 0.2%; Polyether defoamer: 0.15%; Deionized water: Top up to 100%.

[0038] The preparation method is the same as in Example 1.

[0039] Quality inspection results: Fluoroquinolones content 14.9%, pyraclostrobin content 15.2%, pH 7.0, suspension rate 99.2%, wet sieve test pass rate ≥99%, persistent foaming amount ≤15mL, low temperature stability qualified, thermal storage decomposition rate ≤2.0%, particle size D90=3.52μm.

[0040] Example 3: 50% Fluquinazon·Pyraclostrobin Water Dispersible Granules (WG) Fluquinazon technical grade: 20.0%; Pyraclostrobin technical grade: 30.0%; Polycarboxylate dispersant: 6.0%; Calcium lignosulfonate: 4.0%; BX (partially split powder): 2.0%; Ammonium sulfate: 15.0%; Corn starch: 8.0%; Kaolin: Add to 100%.

[0041] Preparation method: Fluquinazon technical grade, pyraclostrobin technical grade, dispersant, wetting agent, disintegrant, filler, and other adjuvants are mixed evenly according to the formula ratio. The mixture is then pulverized using an air jet mill until the fineness meets the requirements (≥98% passing through a 45μm sieve). An appropriate amount of deionized water is added to the mixer and kneaded until the material can be formed into a clump by hand but easily dispersed upon light pressing. The mixture is then transferred to a low-temperature extrusion granulator for granulation. The wet granules are placed in a fluidized bed dryer and dried at 45±2℃ until the moisture content is ≤3%. After sieving (40-60 mesh), 50% fluquinazon·pyraclostrobin water-dispersible granules are obtained.

[0042] Quality inspection results: Fluoroquinolones content 19.9%, pyraclostrobin content 29.8%, moisture 1.2%, suspension rate 96.5%, wetting time 18s, disintegration time ≤45s, dispersibility ≥90%, and thermal decomposition rate ≤2.0%.

[0043] Example 4: 35% Fluquinazon·Pyraclostrobin Dispersible Oil Suspension (OD) Fluquinazon technical grade: 15.0%; Pyraclostrobin technical grade: 20.0%; Castor oil polyoxyethylene ether (EL-20): 8.0%; Tristyrene-based phenolic polyoxyethylene ether (agricultural emulsion 600#): 3.0%; Calcium dodecylbenzenesulfonate: 6.0%; Organic bentonite: 1.5%; Silica: 0.8%; S-200 solvent oil: 20%; Methyl oleate: Make up to 100%.

[0044] Preparation method: Methyl oleate, S-200 solvent oil, castor oil polyoxyethylene ether, tristyrene-phenylphenol polyoxyethylene ether, and calcium dodecylbenzenesulfonate are mixed and stirred until completely dissolved. Organic bentonite and fumed silica are added and dispersed evenly under high-speed shearing. Then, fluquinacridone and pyraclostrobin technical materials are added, and after high-speed shearing pre-dispersion, the mixture is transferred to a sand mill and ground until the particle size D90 ≤ 5 μm, thus obtaining a 35% fluquinacridone·pyraclostrobin dispersible oil suspension.

[0045] Quality inspection results: Fluoroquinolones content 14.9%, pyraclostrobin content 19.8%, pH 6.2, suspension rate 97.8%, wet sieve test pass rate ≥98%, dispersibility qualified, pourability qualified, thermal decomposition rate ≤2.2%, particle size D90=4.06μm.

[0046] Example 5: 25% Fluquinazon·Pyraclostrobin Emulsion (EW) Fluquinazon technical grade: 10.0%; Pyraclostrobin technical grade: 15.0%; S-150 aromatic solvent: 15.0%; N-Methylpyrrolidone: 18.0%; Tristyrene-based phenolic polyoxyethylene ether (agricultural emulsion 600#): 4.0%; Calcium dodecylbenzenesulfonate: 2.0%; Castor oil polyoxyethylene ether (EL-10): 2.0%; Xanthan gum: 0.15%; Propylene glycol: 5.0%; Kathon: 0.2%; Defoamer: 0.1%; Deionized water: Top up to 100%.

[0047] Preparation method: Fluquinazon and pyraclostrobin technical materials were dissolved in S-150 aromatic solvent and N-methylpyrrolidone. An emulsifier was added and stirred until completely dissolved to form a homogeneous oil phase. Xanthan gum, propylene glycol, Kathon, and an antifoaming agent were dissolved in deionized water and stirred until completely dissolved to form a homogeneous aqueous phase. Under high-speed shearing conditions of 3000 rpm, the oil phase was slowly added to the aqueous phase, and shearing continued for 20 minutes to obtain a 25% fluquinazon·pyraclostrobin water-in-oil emulsion.

[0048] Quality inspection results: Fluoroquinolones content 9.9%, pyraclostrobin content 14.8%, pH 6.5, emulsion stability (200 times dilution) qualified, pourability qualified, persistent foaming amount ≤25mL, low temperature stability qualified, and thermal storage decomposition rate ≤3.0%.

[0049] Example 6: 40% Fluquinazon·Pyraclostrobin Wettable Powder (WP) Fluquinazon technical grade: 10.0%; Pyraclostrobin technical grade: 30.0%; Calcium lignosulfonate: 5.0%; Naphthalenesulfonate formaldehyde condensate (NNO): 5.0%; Sodium dodecyl sulfate: 2.0%; Silica: 5.0%; Kaolin: Add to 100%.

[0050] Preparation method: Mix the components evenly according to the formula ratio, and pulverize them to fineness (passing rate of ≥99% through 45μm sieve) using an ultra-micro airflow pulverizer to obtain 40% fluquinacrine·pyraclostrobin wettable powder.

[0051] Quality inspection results: Fluoroquinolones content 9.8%, Pyraclostrobin content 29.7%, wetting time ≤12s, suspension rate ≥92%, pH 7.2, thermal decomposition rate ≤2.0%, and fineness (45μm sieve) passing rate 99.2%.

[0052] III. Field efficacy trials 1. Field efficacy trial for controlling rice sheath blight Test location: Huangzhou District, Huanggang City, Hubei Province.

[0053] Experimental crop: Single-season rice, variety Tianyou 8.

[0054] Target disease for control: Rice sheath blight (Rhizoctonia solani).

[0055] Test reagents: Treatment 1: 25% fluquinacrine·pyraclostrobin suspension (prepared in Example 2, fluquinacrine:pyraclostrobin = 1:1), active ingredient dosage 120 g / ha.

[0056] Treatment 2: 25% fluquinacrine·pyraclostrobin suspension concentrate, active ingredient dosage 150g / ha.

[0057] Treatment 3: 25% fluquinacrine·pyraclostrobin suspension concentrate, active ingredient dosage 180g / ha.

[0058] Treatment 4: 30% fluquinacrine suspension (single agent), active ingredient dosage 180g / ha.

[0059] Treatment 5: 250 g / L pyraclostrobin suspension concentrate (single agent), active ingredient dosage 225 g / ha.

[0060] Treatment 6: Clean water blank control.

[0061] The residential area is 20 square meters. 2 Each treatment was replicated four times in a randomized block design. The first application of the pesticide was performed at the late tillering stage of rice (early stage of sheath blight), followed by a second application 7 days later, for a total of two applications. The pesticide was diluted with 60 kg of water per mu (approximately 0.067 hectares) for conventional spraying. The disease index was assessed 14 days after the second application to calculate the control effect. A 0-9 grade system was used for grading (0: disease-free; 1: disease on the fourth leaf sheath and below; 3: disease on the third leaf sheath and below; 5: disease on the second leaf sheath and below; 7: disease on the flag leaf and below; 9: complete plant death).

[0062] Table 5: Field efficacy test results of the combination of fluquinacrine and pyraclostrobin for controlling rice sheath blight

[0063] Table 5 shows the results of field trials, indicating that the control efficacy of a 1:1 mixture of fluquinacrine and pyraclostrobin against rice sheath blight was 91.2%-96.5% within the effective ingredient dosage range of 120-180 g / ha. The control efficacy of the 150 g / ha mixture (93.7%) was significantly better than that of 180 g / ha fluquinacrine alone (85.3%) and 225 g / ha pyraclostrobin alone (87.8%). The control efficacy of the 180 g / ha mixture (96.5%) was significantly better than the two single-agent controls. This demonstrates that the effective ingredient dosage can be reduced by 20-40% after mixing with the mixture compared to single agents, while the control efficacy is significantly improved.

[0064] 2. Field efficacy trial of pesticides for controlling rice blast. Test location: Xiushui County, Jiujiang City, Jiangxi Province.

[0065] Experimental crop: medium-season rice, variety Zhennuo 19 (highly susceptible to rice blast).

[0066] Target disease for prevention and control: Rice blast (Magnaporthe oryzae).

[0067] Test reagents: Treatment 1: 30% fluquinacrine·pyraclostrobin suspension (prepared in Example 2, fluquinacrine:pyraclostrobin = 1:1), active ingredient dosage 150 g / ha.

[0068] Treatment 2: 30% fluquinacrine·pyraclostrobin suspension concentrate, active ingredient dosage 180g / ha.

[0069] Treatment 3: 30% fluquinacrine·pyraclostrobin suspension concentrate, active ingredient dosage 210g / ha.

[0070] Treatment 4: 30% fluquinacrine suspension (single agent), active ingredient dosage 210g / ha.

[0071] Treatment 5: 250 g / L pyraclostrobin suspension concentrate (single agent), active ingredient dosage 225 g / ha.

[0072] Treatment 6: Clean water blank control.

[0073] The residential area is 25 square meters. 2 Each treatment was replicated four times in a randomized block design. The first application of the pesticide was given at the early heading stage of rice, followed by a second application 7-10 days later, for a total of two applications. The pesticide was diluted with 50 kg of water per mu (approximately 0.067 hectares) using a conventional spraying method. The panicle blast disease index was assessed 20 days after the second application to calculate the control effect. Panicle blast grading standards (per panicle): Grade 0: No disease; Grade 1: Loss less than 5% per panicle; Grade 3: Loss 6-20% per panicle; Grade 5: Loss 21-50% per panicle; Grade 7: Loss 51-70% per panicle; Grade 9: Loss 71-100% per panicle.

[0074] Table 6: Field efficacy trial results of the combination of fluquinacrine and pyraclostrobin for controlling rice blast.

[0075] The field trial results for rice blast in Table 6 show that the control efficacy of the compound treatments was 72.8-81.8% within the effective ingredient dosage range of 150-210 g / ha. The control efficacy of the 210 g / ha compound treatment (81.8%) was significantly better than that of the same dosage of fluquinacridone (64.3%) and pyraclostrobin (69.5%), demonstrating a significant synergistic effect.

[0076] 3. Field efficacy trial of pesticides for controlling wheat powdery mildew. Test location: Yongqiao District, Suzhou City, Anhui Province.

[0077] Experimental crop: wheat, variety Wanken Nuo 1.

[0078] Target disease for prevention and control: Wheat powdery mildew (Blumeria graminis).

[0079] Test reagents: Treatment 1: 35% fluquinacrine·pyraclostrobin dispersible oil suspension (prepared in Example 4, fluquinacrine:pyraclostrobin = 3:4), active ingredient dosage 120 g / ha.

[0080] Treatment 2: 35% dispersible oil suspension, active ingredient dosage 150g / hectare.

[0081] Treatment 3: 35% dispersible oil suspension, active ingredient dosage 180g / hectare.

[0082] Treatment 4: 30% fluquinacrine suspension (single agent), active ingredient dosage 180g / ha.

[0083] Treatment 5: 250 g / L pyraclostrobin suspension concentrate (single agent), active ingredient dosage 200 g / ha.

[0084] Treatment 6: Clean water blank control.

[0085] The residential area is 24 square meters. 2 Each treatment was replicated four times in a randomized block design. The first application of the pesticide was given at the initial stage of wheat powdery mildew infection, followed by a second application 10 days later, for a total of two applications. The pesticide was diluted with 45 kg of water per mu (approximately 0.067 hectares) using conventional spraying. The disease index was assessed 10 days after the second application to calculate the control effect. Leaf grading standards (0–9): Grade 0: No lesions; Grade 1: Lesions covering less than 5% of leaf area; Grade 3: 6-15%; Grade 5: 16-25%; Grade 7: 26-50%; Grade 9: Over 50%.

[0086] Table 7: Field efficacy trial results of the combination of fluquinacrine and pyraclostrobin for controlling wheat powdery mildew.

[0087] The field trial results for powdery mildew in Table 7 show that the combination of fluquinacrine and pyraclostrobin (3:4) at a dosage of 180 g / ha achieved a control efficacy of 83.0%, which is significantly better than fluquinacrine alone (58.3%) and pyraclostrobin alone (63.9%) at the same dosage, confirming the superiority of the combination in the control of wheat powdery mildew.

[0088] 4. Field efficacy trials of pesticides for controlling wheat scab Test location: Suiyang District, Shangqiu City, Henan Province.

[0089] Experimental crop: wheat, variety Zhoumai 22.

[0090] Target disease for prevention and control: Wheat scab (Fusarium graminearum).

[0091] Test reagents: Treatment 1: 25% fluquinacrine·pyraclostrobin emulsion (prepared in Example 5, fluquinacrine:pyraclostrobin = 2:3), active ingredient dosage 120 g / ha.

[0092] Treatment 2: 25% water-in-oil emulsion, active ingredient dosage 150g / ha.

[0093] Treatment 3: 25% water-in-oil emulsion, active ingredient dosage 180g / ha.

[0094] Treatment 4: 30% fluquinacrine suspension (single agent), active ingredient dosage 180g / ha.

[0095] Treatment 5: 250 g / L pyraclostrobin suspension concentrate (single agent), active ingredient dosage 200 g / ha.

[0096] Treatment 6: Clean water blank control.

[0097] The residential area is 30 square meters. 2 Each treatment was replicated four times in a randomized block design. The first application of the pesticide was given at the early flowering stage of wheat, followed by a second application 10 days later, for a total of two applications. The pesticide was diluted with 45 kg of water per mu (approximately 0.067 hectares) for spraying. Disease index was assessed 10 days after the second application to calculate the control effect. The panicle grading standards (0–7) were as follows: Grade 0: No disease in the entire panicle; Grade 1: Less than 1 / 4 of the panicle is diseased; Grade 3: 1 / 4–1 / 2; Grade 5: 1 / 2–3 / 4; Grade 7: More than 3 / 4.

[0098] Table 8: Field efficacy trial results of the combination of fluquinacrine and pyraclostrobin for controlling wheat scab.

[0099] The field trial results for Fusarium head blight in Table 8 show that the control efficacy of the compound treatment in the range of 120-180 g / ha was 74.6-85.1%. The control efficacy of the compound treatment at 180 g / ha (85.1%) was significantly better than that of the two single-agent controls (56.3% and 66.8%), indicating that the control effect of the compound treatment on Fusarium head blight was greatly improved.

[0100] It should be noted that the average disease index in the above tables refers to the severity of crop disease. The higher the disease index value, the more severe the disease. Level 0 corresponds to no disease, levels 1, 3, 5, 7, and 9 represent the severity of the disease from mild to severe (the level values ​​are 1, 3, 5, 7, and 9 respectively), and the highest level value is the highest level value in the grading standard (usually 9 or 7). The calculation formula is as follows:

[0101] Average control efficacy (average control effect) refers to the degree to which a pesticide treatment reduces disease compared to the control group, i.e., the pesticide's control ability. A higher efficacy value indicates better control. 0% means completely ineffective, with no difference from the control group, while 100% means complete control, with no disease in the treated area. The calculation formula is:

[0102] IV. Safety Evaluation In all the above field trials, rice and wheat in each compound treatment area grew normally, and no symptoms of phytotoxicity such as leaf yellowing, curling, scorching, dwarfing, or deformity were observed. Even when applied at twice the recommended dosage, crop growth was not adversely affected. This indicates that the compound composition of fluquinacrine and pyraclostrobin is safe and reliable for rice and wheat within the dosage range recommended by this invention.

[0103] V. Comparative Trial of Shelf Life To compare the difference in the duration of action between the compound fungicide and the single agent of this invention, in the field efficacy test of rice sheath blight, the disease index of each treatment area was investigated at 7, 14, 21 and 28 days after the second application, and the change of control efficacy over time was calculated. The results are shown in Table 9.

[0104] Table 9: Comparison of the duration of action between compound fungicides and single agents (against rice sheath blight)

[0105] The results of the efficacy duration test showed that the compound treatment achieved a high efficacy of 91.5% after 7 days of application, reached a peak of 93.7% after 14 days, maintained at 91.2% after 21 days, and remained at 87.4% after 28 days. In contrast, the efficacy of the two single-agent controls decreased to 80.6% and 83.5% respectively after 21 days, and further decreased to 74.2% and 78.6% after 28 days. Therefore, the efficacy duration of the compound composition of this invention is significantly better than that of the individual single agents used alone, maintaining a high level of efficacy for more than 21 days, which helps to reduce the number of applications and lower production costs.

[0106] The above-described embodiments are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A compound composition of quinclorac and pyraclostrobin, wherein the compound composition comprises two active ingredients, quinclorac and pyraclostrobin, and the mass ratio of quinclorac to pyraclostrobin is 40:1 to 1:

40.

2. The compound composition of fluquinacrine and pyraclostrobin according to claim 1, characterized in that, The mass ratio of fluquinacrine to pyraclostrobin is 5:1 to 1:

5.

3. The compound composition of fluquinacrine and pyraclostrobin according to claim 2, characterized in that, The mass ratio of fluquinacrine to pyraclostrobin is 5:1, 2:1, 1:1, 1:2, or 1:

5.

4. A bactericide, characterized in that, The bactericide contains the compound composition as described in any one of claims 1-3, as well as a carrier and adjuvants.

5. A bactericide according to claim 4, characterized in that, The compound composition comprises 25-50% by mass in the bactericide.

6. A bactericide according to claim 4, characterized in that, The bactericide is formulated as any one of the following: suspension concentrate, dispersible oil suspension concentrate, water-dispersible granules, wettable powder, water emulsion, microemulsion, emulsifiable concentrate, microcapsule suspension concentrate, or suspension emulsion.

7. The application of the fungicide as described in claim 4 in the control of fungal diseases in crops.

8. The application according to claim 7, characterized in that, The crop is rice or wheat, and the fungal disease is rice sheath blight, rice blast, wheat powdery mildew, or wheat scab.

9. The application according to claim 7, characterized in that, The application method of the fungicide is as follows: in the early stage of disease occurrence or the initial stage of disease, dilute the fungicide with water and spray it evenly on the crop leaves. The effective ingredient dosage is 150-450 grams / hectare. The application interval is 7-14 days, and the application is 1-3 times.

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