Bactericidal composition and application thereof

Abstract

The invention belongs to the technical field of pesticide sterilization, and discloses a sterilization composition and application thereof.The sterilization composition comprises an active component A and an active component B. The active component A is feneptadoquin, the active component B is any one of pyraclostrobin and trifloxystrobin, and the mass ratio of the active component A to the active component B is 1: 26-30: 1. The bactericidal composition disclosed by the invention has a good prevention and treatment effect on various plant pathogenic bacteria, the dosage is reduced, the production cost is reduced, and the bactericidal composition is safe to the environment.

Description

Technical Field

[0001] The invention belongs to the technical field of pesticide sterilization and discloses a sterilization composition and application thereof. Background Art

[0002] Pyraclostrobin is a broad-spectrum methoxyacrylate fungicide that inhibits mitochondrial respiration, leading to cell death. It has protective, therapeutic, and leaf penetration and conduction effects. It is mainly used to prevent and treat various diseases caused by fungi on crops. Pyraclostrobin has good control effects on wheat powdery mildew and ergot.

[0003] Trifloxystrobin is a methoxyacrylate fungicide that works by inhibiting the mitochondrial respiration of pathogens. It is highly safe, has no mutagenic, teratogenic or carcinogenic effects, has no adverse effects on reproduction, and can be quickly eliminated in soil, surface water and other environments. Trifloxystrobin has a broad spectrum of fungicides and can prevent and treat diseases of ascomycetes, basidiomycetes, deuteromycetes, and oomycetes. It is used in many crops, has high activity, and is resistant to rain erosion.

[0004] Strobilurins pesticides are a new type of low-toxic, highly active, broad-spectrum, systemic fungicide developed based on natural β-methoxyacrylate derivatives from the mycelium of Strobilurinus strobilurans. They have protective, therapeutic, and eradication effects. They have good biological activity against pathogenic fungi such as Oomycetes, Ascomycetes, Basidiomycetes, Deuteromycetes, and Oomycetes, and can prevent and control diseases such as powdery mildew, rice blast, rust, and downy mildew of various crops. Their mechanism of action is to bind to the oxidation site (Qo) of coenzyme Q in the mitochondrial complex III of pathogens, preventing the transfer of electrons from cytochrome b to cytochrome c1, thereby hindering the synthesis of cellular adenosine triphosphate (ATP), causing the pathogens to die due to lack of energy. Strobilurins fungicides are the world's largest-selling fungicides, with the characteristics of broad spectrum, high efficiency, and safety.

[0005] However, methoxyacrylate fungicides have a single site of action and are prone to cause resistance in pathogens. They have a high potential risk of drug resistance and are very likely to develop drug resistance during actual application. Summary of the invention

[0006] Based on the above situation, the purpose of the present invention is to provide a fungicide composition and its application, which is compounded by different active ingredients to effectively reduce production costs. The fungicide composition can be used to prevent and treat various diseases caused by plant pathogens, especially wheat head blight and rice blast fungus, and can delay the generation and development of drug resistance of pathogens while reducing the dosage.

[0007] In order to achieve the above-mentioned object, the present invention adopts the following technical scheme: a bactericidal composition and its application, wherein the bactericidal composition comprises an active ingredient A and an active ingredient B, wherein the active ingredient A is feneptamidoquin, and the active ingredient B is any one of pyraclostrobin and trifloxystrobin, and the mass ratio of the active ingredient A to the active ingredient B is 1:26 to 30:1, or any value within the above numerical range.

[0008] Furthermore, the active ingredient B is pyraclostrobin, and the mass ratio of the active ingredient A to the active ingredient B is 1:25 to 30:1, or any value within the above numerical range;

[0009] The active ingredient B is trifloxystrobin, and the mass ratio of the active ingredient A to the active ingredient B is 1:26 to 20:1, or any value within the above numerical range.

[0010] Furthermore, the active ingredient B is pyraclostrobin, and the mass ratio of the active ingredient A to the active ingredient B is 1:18 to 22:1, or any value within the above numerical range;

[0011] The active ingredient B is trifloxystrobin, and the mass ratio of the active ingredient A to the active ingredient B is 1:18 to 15:1, or any value within the above numerical range.

[0012] Furthermore, the active ingredient B is pyraclostrobin, and the mass ratio of the active ingredient A to the active ingredient B is 1:15 to 20:1, or any value within the above numerical range;

[0013] The active ingredient B is trifloxystrobin, and the mass ratio of the active ingredient A to the active ingredient B is 1:15 to 10:1, or any value within the above numerical range.

[0014] Furthermore, based on the total weight of the bactericidal composition being 100 wt%, the sum of the contents of the active ingredient A and the active ingredient B in the bactericidal composition is 1 to 80 wt%, preferably 2 to 70 wt%.

[0015] Furthermore, the bactericidal composition includes auxiliary ingredients in addition to the active ingredients, and the auxiliary ingredients include one or more of a wetting agent, a dispersant, an emulsifier, a thickener, a disintegrant, an antifreeze agent, a defoaming agent, a solvent, a stabilizer, a film-forming agent, a warning color, a penetrant and a carrier.

[0016] Furthermore, the bactericidal composition can be prepared into a solid preparation or liquid preparation dosage form permitted in agriculture;

[0017] Furthermore, the solid preparation is a water-dispersible granule, a wettable powder or a granule, and the liquid preparation is a suspension, an aqueous emulsion, an emulsifiable concentrate, a microemulsion, a seed treatment suspension, a microcapsule suspension or a dispersible oil suspension.

[0018] The invention also discloses the application of the bactericidal composition in preventing and controlling pathogenic bacteria of agricultural, forestry or horticultural plants.

[0019] Further, the plant pathogenic bacteria include Botrytis cinerea, Pyricularia oryae, Fusarium moniliforrme, Fusarium graminearum, Rhizoctonia solani and / or Blumeria graminis f.sp.tritici.

[0020] Furthermore, the plant pathogenic bacteria are Fusarium graminearum and Pyricularia oryae.

[0021] A fungicidal composition is applied to plant pathogens and / or their environment, or plants, plant parts, plant propagation materials and subsequently grown plant organs, soil or cultivation media, materials in an agronomically effective and substantially non-phytotoxic application rate by seed treatment, foliar application, stem application, drench, dripping, pouring, spraying, misting, dusting, spreading or fumigation.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] 1) The fungicidal composition of the present invention uses a combination of agents with different mechanisms of action to improve the control effect and delay the development of drug resistance in pathogenic bacteria;

[0024] 2) The fungicide composition of the present invention has low toxicity and leaves less residue in crops and soil, thus effectively reducing environmental pollution and drug residue;

[0025] 3) The fungicidal composition of the present invention exhibits good control effects on a variety of plant pathogens, reduces the dosage of pesticides used, reduces production costs, and alleviates environmental pressure. DETAILED DESCRIPTION

[0026] In order to better illustrate the effective control effect of the present invention, the above-mentioned embodiment agent is used to make the technical scheme, purpose and advantages of the present invention clearer, and the present invention is described with the following specific examples, but the present invention is not limited to these examples. The technical effect test of the present invention adopts a combination of indoor biological test and field test.

[0027] Preparation Example:

[0028] Preparation Example 1: 24% feneptamidoquin·pyraclostrobin suspension (1:5)

[0029] Formula composition: 4% feneptamidoquin, 20% pyraclostrobin, 2% succinate sulfonate, 1% naphthalene sulfonate formaldehyde condensate, 4% tristyrylphenol ethoxylate phosphate, 0.25% xanthan gum, 1% magnesium aluminum silicate, 3% ethylene glycol, 0.5% sodium benzoate, 0.5% silicone oil, deionized water to make up the balance;

[0030] Preparation method: According to the formula ratio, the active ingredients, surfactants and other functional additives are placed in a reactor in sequence, water is added to mix evenly, and the suspension product is obtained by high-speed shearing, wet sand grinding, and finally homogenization filtration.

[0031] Preparation Example 2: 2.7% feneptamidoquin·pyraclostrobin emulsifiable concentrate (8:1)

[0032] Formula composition: 2.4% feneptamidoquin, 0.3% pyraclostrobin, 12% DMF, 15% tristyrylphenol polyoxyethylene ether, 3% calcium dodecylbenzenesulfonate, 20% propylene carbonate, and trimethylbenzene makes up the balance;

[0033] Preparation method: according to the formula ratio, the measured active ingredients, solvents and co-solvents are added into a mixing kettle and stirred to dissolve, then an emulsifier is added, the remaining amount is supplemented with the remaining solvent, and the mixture is stirred evenly in a stirring kettle, and the desired emulsifiable concentrate is obtained after filtering.

[0034] Preparation Example 3: 1.2% feneptamidoquin·pyraclostrobin microemulsion (5:1)

[0035] Formula composition: 1% feneptamidoquin, 0.2% pyraclostrobin, 20% cyclohexanone, 10% glycerol fatty acid ester polyoxyethylene ether, 2% isomeric tridecanol polyoxyethylene ether, 5% tristyrylphenol polyoxyethylene ether, 2% styrylphenol polyoxyethylene ether sulfate, 0.1% silicone defoamer, and deionized water to make up the balance;

[0036] Preparation method: According to the formula ratio, the active ingredients, solvents, emulsifiers, etc. are mixed to obtain the oil phase, the antifreeze agent and water are mixed to obtain the water phase, the oil phase is added to the water phase under stirring and stirred evenly, and the shearing is continued for 10 minutes, and then the defoaming agent is added and stirred evenly to obtain small droplets of oil phase particles of 0.01 to 0.1 microns, that is, the microemulsion product is obtained.

[0037] Preparation Example 4: 4% feneptamidoquin·pyraclostrobin emulsion in water (1:3)

[0038] Formula composition: 1% feneptamidoquin, 3% pyraclostrobin, 5% trimethylbenzene, 15% cyclohexanone, 1% BHT, 2% castor oil polyoxyethylene ether phosphate, 6% EO-PO block copolymer, 3% ethylene glycol, 0.05% silicone defoamer, 0.2% xanthan gum, 0.05% potassium benzisothiazolinone, and deionized water to make up the balance;

[0039] Preparation method: According to the formula ratio, the active ingredient is dissolved in the solvent and an emulsifier is added to dissolve it into a uniform oil phase. Deionized water, antifreeze, etc. are mixed together to form a uniform water phase. Under high-speed shearing, the oil phase is added to the water phase. After shearing to a qualified particle size, a defoamer, a thickener, and a preservative are added and stirred evenly to form a well-dispersed water emulsion product.

[0040] Preparation Example 5: 16% feneptamidoquin·pyraclostrobin dispersible oil suspension (3:1)

[0041] Formula composition: 12% feneptamidoquin, 4% pyraclostrobin, 2% calcium dodecylbenzene sulfonate, 12% sorbitan oleate polyoxyethylene ether, 4% fatty amine polyoxyethylene ether, 2% naphthalene sulfonate formaldehyde condensate, 1% silicon dioxide, 1% organic bentonite, 20% 200# solvent oil, and methyl oleate to make up the balance;

[0042] Preparation method: According to the formula ratio, the active ingredients, surfactants and other functional additives are placed in the reactor in sequence, oil is added and mixed evenly, and the dispersible oil suspension product is obtained by high-speed shearing, wet sand grinding, and finally homogenization filtration.

[0043] Preparation Example 6: 33% feneptamidoquin·pyraclostrobin water dispersible granules (10:1)

[0044] Formula composition: 30% feneptamidoquin, 3% pyraclostrobin, 2% sodium lauryl sulfate, 10% naphthalenesulfonate formaldehyde condensate, 5% polycarboxylic acid sodium salt, 2% fatty alcohol polyoxyethylene ether sulfate, 5% white carbon black, 25% starch, kaolin makes up the balance;

[0045] Preparation method: according to the formula ratio, the active ingredient is added to the carrier, and the surfactant and other functional additives are added thereto, mixed, and after air flow grinding, 10-25% of water is added, and then the water-dispersible granule product is obtained by kneading, granulating, drying and sieving; or the crushed powder is sprayed with water in a boiling granulator, granulated, dried, and then sieved to obtain the product.

[0046] Preparation Example 7: 36% feneptamidoquin·pyraclostrobin wettable powder (1:8)

[0047] Formula composition: 4% feneptamidoquin, 32% pyraclostrobin, 3% sodium lignin sulfonate, 5% fatty alcohol polyoxyethylene ether sulfate, 2% BX powder, 5% white carbon black, and kaolin makes up the balance;

[0048] Preparation method: The active ingredients, dispersants, wetting agents and fillers are mixed according to the formula ratio, uniformly stirred in a stirring kettle, and pulverized and mixed uniformly for multiple times by a jet mill to prepare the wettable powder of the composition of the present invention.

[0049] Preparation Example 8: 18% feneptamidoquin·trifloxystrobin suspension (2:1)

[0050] Formula composition: 12% feneptamidoquin, 6% trifloxystrobin, 3% tristyrylphenol polyoxyethylene ether phosphate, 4% isomeric tridecanol polyoxyethylene ether, 1% sodium lignin sulfonate, 0.25% xanthan gum, 5% ethylene glycol, 0.1% sodium benzoate, 0.5% silicone oil, and deionized water to make up the balance;

[0051] Preparation method: Same as Preparation Example 1.

[0052] Preparation Example 9: 9% feneptamidoquin·trifloxystrobin emulsifiable concentrate (1:5)

[0053] Formula composition: 1.5% feneptamidoquin, 7.5% trifloxystrobin, 18% N-methylpyrrolidone, 12% alkyl aryl polyoxyethylene ether polyoxypropylene ether, 3% calcium dodecylbenzene sulfonate, 10% DMF, and trimethylbenzene makes up the balance;

[0054] Preparation method: Same as Preparation Example 2.

[0055] Preparation Example 10: 7% feneptamidoquin·trifloxystrobin microemulsion (1:6)

[0056] Formula composition: 1% feneptamidoquin, 6% trifloxystrobin, 13% trimethylbenzene, 20% cyclohexanone, 15% glycerol fatty acid ester polyoxyethylene ether, 3% EO-PO block copolymer, 2% sodium alkyl polyoxyethylene ether sulfonate, 4% ethylene glycol, 0.05% silicone defoamer, and deionized water to make up the balance.

[0057] Preparation method: Same as Preparation Example 3.

[0058] Preparation Example 11: 1.5% feneptamidoquin·trifloxystrobin aqueous emulsion (4:1)

[0059] Formula composition: 1.2% feneptamidoquin, 0.3% trifloxystrobin, 3% glycerol fatty acid ester polyoxyethylene ether, 3% polyoxyethylene sorbitan monooleate, 15% cyclohexanone, 0.1% xanthan gum, 0.1% isothiazolinone, 5% glycerol, 1.5% urea, 0.5% sodium sorbate, 0.1% organosilicon defoamer, and deionized water to make up the balance;

[0060] Preparation method: Same as Preparation Example 4.

[0061] Preparation Example 12: 31.5% feneptamidoquin·trifloxystrobin water dispersible granules (4:5)

[0062] Formula composition: 14% feneptamidoquin, 17.5% trifloxystrobin, 10% succinate sulfonate, 3% lakai powder BX, 6% polycarboxylate sodium salt, 5% white sugar, and kaolin makes up the balance.

[0063] Preparation method: Same as Preparation Example 6.

[0064] Preparation Example 13: 27% feneptamidoquin·trifloxystrobin wettable powder (8:1)

[0065] Formula composition: 24% feneptamidoquin, 3% trifloxystrobin, 2% sodium dodecyl sulfate, 3% sodium dioctyl sulfosuccinate, 5% naphthalene sulfonate formaldehyde condensate, 10% kaolin, 5% white carbon black, and bentonite makes up the balance;

[0066] Preparation method: Same as Preparation Example 7.

[0067] Indoor activity measurement test:

[0068] Example 1: Indoor biological activity assay test of rice blast

[0069] Test basis: NY / T 1156.2-2006 "Guidelines for Indoor Bioassay Tests of Pesticides - Fungicides Part 2: Plate Method for Inhibition of Pathogenic Fungal Mycelial Growth", NY / T 1156.6-2006 "Guidelines for Indoor Bioassay Tests of Pesticides - Fungicides Part 6: Determination of Combined Action of Mixtures".

[0070] Test target: Rice blast pathogen (Pyricularia oryae Cav.), strain continuously cultured indoors.

[0071] Test agents: feneptamidoquin, pyraclostrobin, and trifloxystrobin technical drugs.

[0072] Preparation of medicine: dissolve the above raw medicine with a suitable solvent, and then dilute it with 0.1% Tween-80 aqueous solution. According to the activity of the medicine, set the required series of mass concentrations.

[0073] Preparation of culture medium: Before solidification, quantitatively dispense AEA culture medium into glass bottles and sterilize at high temperature. Under aseptic operation conditions, use a pipette to inject 1 mL of the corresponding mother solution to be tested into each bottle of 39 mL of quantitative sterilized AEA culture medium heated and melted, from low concentration to high concentration, shake well, and dispense into 4 culture dishes with a diameter of 9 mm to prepare drug-containing plates of corresponding concentrations. Add sterilized 0.1% Tween-80 aqueous solution as a blank control.

[0074] Test method: Under aseptic conditions, use a sterile puncher to cut a bacterial cake from the edge of the colony and invert it in the center of the drug-containing plate. Place a bacterial cake in each culture dish. The culture dish after inoculation is placed in a biochemical incubator at (28±1)℃. Investigate the growth of pathogenic mycelium according to the growth of mycelium in the blank control culture dish. Measure the colony diameter of each colony with a caliper in millimeters (mm). Measure the diameter of each colony vertically once using the cross method and take the average value.

[0075] Calculation method: According to the survey results, the mycelial growth inhibition rate of each treatment concentration on the target bacteria was calculated according to the following formula, and the unit is percentage (%).

[0076] D=D1-D2

[0077] Where:

[0078] D——colony growth diameter;

[0079] D1——colony diameter;

[0080] D2——diameter of mushroom cake.

[0081]

[0082] I——hyphae growth inhibition rate;

[0083] D0——blank control colony growth diameter;

[0084] D t ——The growth diameter of the colony after treatment with chemicals.

[0085] Test statistics: Use statistical analysis system to analyze and process data, and find out the toxicity regression line and EC 50 The activity of the test agent on the biological test material was evaluated by using the value and correlation coefficient.

[0086] The co-toxicity coefficient (CTC value) of the mixture is calculated by the following formula:

[0087]

[0088] Where:

[0089] ATI——Actual Toxicity Index of Mixture;

[0090] S——EC of standard fungicide 50 , the unit is milligrams per liter (mg / L);

[0091] M——EC of the mixture 50 , the unit is milligrams per liter (mg / L).

[0092] TTI=TI A ×P A +TI B ×P B

[0093] Where:

[0094] TTI – Theoretical Toxicity Index of Mixtures;

[0095] TI A ——A: toxicity index of the agent;

[0096] P A ——The percentage of agent A in the mixture, in percentage (%);

[0097] TI B ——Toxicity index of agent B;

[0098] P B ——The percentage of agent B in the mixture, in percentage (%).

[0099]

[0100] Where:

[0101] CTC – Co-toxicity coefficient;

[0102] ATI——Actual Toxicity Index of Mixture;

[0103] TTI - Theoretical Toxicity Index of Mixture.

[0104] The co-toxicity coefficient of the combination CTC≥120 shows a synergistic effect; CTC≤80 shows an antagonistic effect; 80<CTC<120 shows an additive effect.

[0105] The results of the indoor biological activity test are shown in the following table:

[0106] Table 1 Results of indoor biological activity test of feneptamidoquin and pyraclostrobin against rice blast pathogen

[0107] Test drug Virulence regression equation Correlation coefficient R <![CDATA[EC 50 (mg.L -1 )]]> Co-toxicity coefficient Feneptamidoquin(A) y=1.5071x+4.6239 0.9963 1.7763 - Pyraclostrobin(B) y=1.5323x+6.5064 0.9932 0.1040 - A:B(1:32) y=1.6202x+6.5265 0.9955 0.1142 93.743 A:B(1:24) y=1.4652x+6.4362 0.9966 0.1047 103.218 A:B(1:18) y=1.4622x+6.5304 0.9973 0.0898 121.851 A:B(1:8) y=1.5935x+6.7632 0.9990 0.0783 148.340 A:B(1:5) y=1.5578x+6.7921 0.9959 0.0707 174.477 A:B(5:1) y=1.4689x+5.8853 0.9910 0.2496 193.387 A:B(8:1) y=1.5966x+5.7371 0.9989 0.3454 184.549 A:B(15:1) y=1.3808x+5.2995 0.9944 0.6069 145.978 A:B(22:1) y=1.5051x+5.1125 0.9989 0.8419 124.174 A:B(25:1) y=1.4617x+5.0258 0.9970 0.9601 114.314 A:B(30:1) y=1.5102x+4.8246 0.9977 1.3065 89.523

[0108] The results of the indoor test show that the combination of feneptamidoquin and pyraclostrobin has a relatively obvious inhibitory effect on the growth of rice blast fungus. The mass ratio of feneptamidoquin to pyraclostrobin is 1:18-22:1, and the co-toxicity coefficient to rice blast is greater than 120, showing a synergistic effect; the mass ratio of feneptamidoquin to pyraclostrobin is 1:8-15:1, and the co-toxicity coefficient to rice blast is greater than 140, showing a significant synergistic effect; the mass ratio of feneptamidoquin to pyraclostrobin is 1:5-8:1, and the co-toxicity coefficient is greater than 150, showing a significant synergistic effect.

[0109] Table 2 Results of indoor biological activity test of feneptamidoquin and trifloxystrobin against rice blast fungus

[0110]

[0111]

[0112] The results of the indoor test show that the combination of feneptamidoquin and trifloxystrobin has a relatively obvious inhibitory effect on the growth of rice blast fungus. The mass ratio of feneptamidoquin to trifloxystrobin is 1:26-20:1, and the co-toxicity coefficient to rice blast is greater than 120, showing a synergistic effect; the mass ratio of feneptamidoquin to trifloxystrobin is 1:15-10:1, and the co-toxicity coefficient is greater than 130, showing a significant synergistic effect; the mass ratio of feneptamidoquin to trifloxystrobin is 1:8-4:1, and the co-toxicity coefficient is greater than 140, showing a significant synergistic effect.

[0113] Example 2: Indoor biological activity test of wheat scab

[0114] Test basis: The test refers to NY / T 1156.2-2006 agricultural industry standard "Guidelines for Indoor Bioassay Tests of Pesticides - Fungicides Part 2: Plate Method for Inhibition of Pathogen Mycelial Growth".

[0115] Test target: Fusarium graminearum.

[0116] Instruments and equipment: wet heat sterilizer, clean workbench, constant temperature and light incubator, electric drum windproof drying oven, 1 / 10,000 electronic balance, pipette, alcohol lamp, small beaker, volumetric flask, triangular flask, culture dish, puncher, inoculator, ruler, etc.

[0117] The target culture conditions were as follows: Fusarium graminearum stored in a refrigerator at 4°C was transferred to potato dextrose agar medium, and cultured in a dark incubator at 26°C for 4 days to activate it and set aside.

[0118] Test agents: feneptamidoquin, pyraclostrobin, and trifloxystrobin technical drugs.

[0119] Preparation of pharmaceutical mother solutions: Dissolve the above original drugs in appropriate solvents to prepare high-concentration mother solutions, and then dilute them with 0.1% Tween 80 aqueous solution to prepare single-dose mother solutions. Design different ratios based on the purpose of mixing and the activity of the pharmaceutical. Each single dose and each group of mixed solutions are configured to the required series of mass concentrations.

[0120] Test repetition: 4 culture dishes for each concentration of the test agent, 1 culture dish for each repetition, for a total of 4 repetitions, and a 0.1% Tween 80 aqueous solution without the agent was used as a blank control.

[0121] Drug treatment: Under aseptic operation conditions, according to the test treatment, the pre-melted and sterilized PDA medium was quantitatively added to the sterile conical flask, and 10 mL of each prepared treatment solution was quantitatively drawn from low concentration to high concentration, and added to the above conical flasks respectively, shaken well, and then poured into 4 culture dishes with a diameter of 9 cm in equal amounts to prepare drug-containing plates of corresponding concentrations. The test set up a 0.1% Tween 80 aqueous solution without adding drugs as a blank control, and each treatment was repeated 4 times.

[0122] Inoculation: Use a sterile puncher to punch the cultured pathogens along the edge of the colony under sterile conditions to obtain a bacterial cake, then gently place the bacterial cake on the prepared drug-containing plate and culture it in a constant temperature incubator at 25°C. When the diameter of the control colony reaches about 2 / 3 of the diameter of the culture dish, use the cross method to measure the diameter of each treated colony and calculate its mycelial growth inhibition rate.

[0123] Data investigation: Investigate the growth of pathogenic mycelium based on the growth of mycelium in the blank control culture dish. Use a ruler to measure the diameter of the colony in centimeters (cm). Measure the diameter of each colony once using the cross method, take the average value, and record the original data of all replicates for each treatment.

[0124] Data statistics and analysis: According to the survey results, the mycelial growth inhibition rate of each treatment concentration on the target bacteria was calculated. The unit is percentage (%) and the calculation result is rounded to two decimal places.

[0125] D=D1-D2

[0126] Where:

[0127] D——colony growth diameter;

[0128] D1——colony diameter;

[0129] D2——diameter of mushroom cake.

[0130]

[0131] I——hyphae growth inhibition rate;

[0132] D0——blank control colony growth diameter;

[0133] D t ——The growth diameter of the colony after treatment with chemicals.

[0134] Test statistics: Use statistical analysis system to analyze and process data, and find out the toxicity regression line and EC 50 The activity of the test agent on the biological test material was evaluated by using the value and correlation coefficient.

[0135] The co-toxicity coefficient (CTC value) of the mixture is calculated by the following formula:

[0136]

[0137] Where:

[0138] ATI——Actual Toxicity Index of Mixture;

[0139] S——EC of standard fungicide 50 , the unit is milligrams per liter (mg / L);

[0140] M——EC of the mixture 50 , the unit is milligrams per liter (mg / L).

[0141] TTI=TI A ×P A +TI B ×P B

[0142] Where:

[0143] TTI – Theoretical Toxicity Index of Mixtures;

[0144] TI A ——A: toxicity index of the agent;

[0145] P A ——The percentage of agent A in the mixture, in percentage (%);

[0146] TI B ——Toxicity index of agent B;

[0147] P B ——The percentage of agent B in the mixture, in percentage (%).

[0148]

[0149] Where:

[0150] CTC – Co-toxicity coefficient;

[0151] ATI——Actual Toxicity Index of Mixture;

[0152] TTI - Theoretical Toxicity Index of Mixture.

[0153] The co-toxicity coefficient of the combination CTC≥120 shows a synergistic effect; CTC≤80 shows an antagonistic effect; 80<CTC<120 shows an additive effect.

[0154] The results of the indoor biological activity test are shown in the following table:

[0155] Table 3 Results of indoor biological activity test of feneptamidoquin and pyraclostrobin against Fusarium graminearum

[0156] Test drug Virulence regression equation Correlation coefficient R <![CDATA[EC 50 (mg.L -1 )]]> Co-toxicity coefficient Feneptamidoquin(A) y=1.4312x+4.1397 0.9972 3.9910 - Pyraclostrobin(B) y=1.4247x+4.6513 0.9914 1.7569 - A:B(1:30) y=1.5088x+4.7297 0.9927 1.5107 118.436 A:B(1:25) y=1.2908x+4.8027 0.9969 1.4219 126.279 A:B(1:15) y=1.4636x+4.8348 0.9955 1.2968 140.392 A:B(1:12) y=1.4859x+4.8832 0.9983 1.1984 153.201 A:B(1:5) y=1.3581x+4.9032 0.9965 1.1783 164.448 A:B(1:3) y=1.3269x+4.9167 0.9996 1.1556 176.774 A:B(3:1) y=1.6614x+4.6453 0.9983 1.6349 185.236 A:B(5:1) y=1.4258x+4.5734 0.9995 1.9917 165.349 A:B(10:1) y=1.5785x+4.3701 0.9987 2.5063 142.747 A:B(20:1) y=1.5415x+4.3040 0.9974 2.8282 133.066 A:B(30:1) y=1.6863x+4.1579 0.9956 3.1579 121.410

[0157] The results of the indoor test show that the combination of feneptamidoquin and pyraclostrobin has a relatively obvious inhibitory effect on the growth of Fusarium graminearum. The mass ratio of feneptamidoquin to pyraclostrobin is 1:25-30:1, and the co-toxicity coefficient to Fusarium graminearum is greater than 120, showing a synergistic effect; the mass ratio of feneptamidoquin to pyraclostrobin is 1:15-20:1, and the co-toxicity coefficient is greater than 130, showing a significant synergistic effect; the mass ratio of feneptamidoquin to pyraclostrobin is 1:15-10:1, and the co-toxicity coefficient is greater than 150, showing a significant synergistic effect.

[0158] Table 4 Results of indoor biological activity test of feneptamidoquin and trifloxystrobin against Fusarium graminearum

[0159]

[0160]

[0161] The results of the indoor test show that the combination of feneptamidoquin and trifloxystrobin has a relatively obvious inhibitory effect on the growth of Fusarium graminearum. The mass ratio of feneptamidoquin to trifloxystrobin is 1:18-15:1, and the co-toxicity coefficient to Fusarium graminearum is greater than 120, showing a synergistic effect; the mass ratio of feneptamidoquin to trifloxystrobin is 1:12-10:1, and the co-toxicity coefficient is greater than 130, showing a significant synergistic effect; the mass ratio of feneptamidoquin to trifloxystrobin is 1:12-8:1, and the co-toxicity coefficient is greater than 140, showing a significant synergistic effect.

[0162] Example 3: Field efficacy test for controlling rice blast

[0163] Test basis: The test refers to GB / T 17980.19-2000 "Guidelines for field efficacy tests (I) Fungicides for the control of rice foliar diseases".

[0164] Test location: The test was conducted in Luotuao Village, Luotuao Town, Luotian County, Hubei Province; rice is grown here all year round. The test site is flat, close to water sources, and convenient for irrigation. The soil is sandy loam with medium fertility. The crop varieties, planting period, growth, fertilizer and water management conditions of each test plot are basically the same.

[0165] Test target: Rice blast disease.

[0166] Experimental crops: Rice (Xinliangyou 233).

[0167] Test drugs: Test drugs and dosages are shown in the table below.

[0168] Experimental design: The experimental design has 8 treatments, and the experimental plots are arranged in completely random blocks; the area of ​​the plots is 30m 2 Each treatment was repeated 4 times, with clean water as a blank control, and protection rows were set up in adjacent plots.

[0169] Application time and number of times: The experiment was conducted once at the rice rupture stage and once at the rice heading stage, for a total of 2 applications. During the application, a 3WBD-I6HBA backpack electric sprayer was used to evenly spray the stems and leaves. No other pesticides were used to control other pests and diseases 20 days before and after the experiment and during the experiment.

[0170] Survey method: Five sampling points were adopted in each plot, 50 ears were surveyed at each point, and a total of 250 ears were surveyed in each plot, for one survey in total. After the second application of pesticides, the number of diseased ears at all levels in each plot was surveyed before the rice was mature and harvested, and the disease index and control effect were calculated.

[0171] Safety investigation of pesticides: During the test, rice grew normally, and the pesticides in the tested concentrations did not cause any damage to rice plants or other non-target organisms.

[0172] The classification records are made according to the following classification method:

[0173] Level 0: no disease;

[0174] Level 1: less than 5% loss per ear (individual branches and stalks are diseased);

[0175] Level 3: 6% to 20% loss per ear (about one-third of the branches and stalks are diseased);

[0176] Level 5: 21% to 50% loss per ear (the neck or main axis of the ear is diseased, and the grains are half-shrunken);

[0177] Level 7: 51% to 70% loss per ear (the neck of the ear is diseased and most of the grains are shrunken);

[0178] Level 9: 71% to 100% loss per ear (the ear neck becomes diseased, resulting in white ears).

[0179] The efficacy is calculated according to the following formula:

[0180]

[0181] The results of the field efficacy test are shown in the following table:

[0182] Table 5 Results of field efficacy test on control of rice blast

[0183] Pharmacy Active ingredient dosage (g / hectare) Disease index Average protection effect Preparation Example 2: 2.7% feneptamidoquin·pyraclostrobin emulsifiable concentrate (8:1) 80 1.67 88.21 Preparation Example 1: 24% feneptamidoquin·pyraclostrobin suspension (1:5) 80 2.06 85.46 Preparation Example 9: 9% feneptamidoquin·trifloxystrobin emulsifiable concentrate (1:5) 80 2.32 83.57 Preparation Example 8: 18% feneptamidoquin·trifloxystrobin suspension (2:1) 80 1.80 87.26 60% Trifloxystrobin water dispersible granules 100 4.40 68.87 9% Pyraclostrobin Microcapsule Suspension 67.5 3.62 74.37 20% feneptamidoquin suspension 150 5.12 63.76 Clear water control / 14.13 /

[0184] From the analysis of the field efficacy test results in the above table, it can be seen that the mixture of feneptamidoquin and pyraclostrobin or trifloxystrobin has a good control effect on rice blast. The rice panicle blast was investigated before the rice matured and was harvested after the application of the medicine. The control effects of the mixed agent Preparation Example 2: 2.7% feneptamidoquin·pyraclostrobin EC (8:1), Preparation Example 1: 24% feneptamidoquin·pyraclostrobin SC (1:5), Preparation Example 9: 9% feneptamidoquin·trifloxystrobin EC (1:5), Preparation Example 8: 18% feneptamidoquin·trifloxystrobin SC (2:1) were 88.21%, 85.46%, 83.57%, and 87.26%, respectively.

[0185] Example 4: Field efficacy test for preventing and controlling wheat scab

[0186] Test basis: The test refers to NY / T 1464.15-2007 "Guidelines for Field Efficacy Tests of Pesticides Part 15: Fungicides for Control of Wheat Fusarium Head Blight".

[0187] Test target: Wheat fusarium wilt.

[0188] Experimental crop: wheat (Yannong No. 19).

[0189] Test location: The test was conducted in a village in Wuyang County, Luohe City, Henan Province. The test field had suffered from severe wheat fusarium wilt in previous years. The soil fertility of the test field was moderate. The cultivation conditions of all test plots were consistent and in line with local good agricultural practices.

[0190] Experimental plot arrangement: A total of 8 treatments were set up in the experiment, including 7 drug treatments and 1 water blank control. The plots of experimental drugs, control drugs and blank control were arranged in random blocks, with an area of ​​20m per plot. 2 , each treatment was repeated 4 times.

[0191] Application time: The experiment was conducted once at the beginning of wheat flowering period. A 3WBD-20L backpack sprayer was used to spray the whole plant to ensure uniform and thorough distribution of droplets. The amount of liquid applied per mu was 35 kg. The cultivation and management measures for each treatment were the same.

[0192] Survey method and time: The disease of wheat was investigated in the late milky stage. Samples were taken at 5 points on the diagonal of each plot, and 100 ears were investigated at each point. The wheat was graded based on the percentage of the dead ear area to the entire ear area, and the number of diseased ears and the total number of ears at each level were recorded.

[0193] Wheat fusarium grading standards:

[0194] Level 0: The whole ear is disease-free;

[0195] Level 1: The dead ear area accounts for less than 1 / 4 of the whole ear area;

[0196] Level 3: The dead ear area accounts for 1 / 4-1 / 2 of the whole ear area;

[0197] Level 5: The dead ear area accounts for 1 / 2-3 / 4 of the whole ear area;

[0198] Level 7: The area of ​​dead ears accounts for more than 3 / 4 of the whole ear area.

[0199] Calculation method of drug efficacy:

[0200]

[0201] The results of the field efficacy test are shown in the following table:

[0202] Table 6 Results of field efficacy test on prevention and treatment of wheat scab

[0203] Drug Name Active ingredient dosage (g / hectare) Disease index Control effect (%) Preparation Example 5: 16% feneptamidoquin·pyraclostrobin dispersible oil suspension (3:1) 120 1.31 92.83 Preparation Example 3: 1.2% feneptamidoquin·pyraclostrobin microemulsion (5:1) 120 2.14 88.25 Preparation Example 10: 7% feneptamidoquin·trifloxystrobin microemulsion (1:6) 120 2.36 87.03 Preparation Example 12: 31.5% feneptamidoquin·trifloxystrobin water dispersible granules (4:5) 120 1.73 90.52 20% feneptamidoquin suspension 150 4.72 74.11 25% pyraclostrobin suspension 130 5.11 71.99 30% Trifloxystrobin SC 180 6.11 66.47 Blank control / 18.24 /

[0204] The field efficacy results showed that the reasonable combination of feneptamidoquin with pyraclostrobin or trifloxystrobin showed good control effect on wheat fusarium rust. The overall control efficacy of each combined preparation was above 87%, which was better than the blank control treatment group of the control single agent.

[0205] It can be seen from indoor toxicity tests and field efficacy tests that the fungicide composition of the present invention exhibits good control effects on wheat ergot and rice blast, is safe for crops, delays the development of drug resistance in pathogenic bacteria, reduces the dosage of the agent used, and reduces the agent residues in agricultural products.

[0206] Although the present invention has been described in detail above with general descriptions and specific implementation schemes, it is obvious to those skilled in the art that some modifications or improvements can be made on the basis of the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention are within the scope of protection claimed by the present invention.

Claims

1. A bactericidal composition and its application, characterized in that: The bactericidal composition comprises an active ingredient A and an active ingredient B, wherein the active ingredient A is feneptamidoquin, and the active ingredient B is any one of pyraclostrobin and trifloxystrobin, and the mass ratio of the active ingredient A to the active ingredient B is 1:26 to 30:

1.

2. The bactericidal composition according to claim 1, characterized in that The active ingredient B is pyraclostrobin, and the mass ratio of the active ingredient A to the active ingredient B is 1:25 to 30:1; The active ingredient B is trifloxystrobin, and the mass ratio of the active ingredient A to the active ingredient B is 1:26 to 20:

1.

3. The bactericidal composition according to claim 2, characterized in that The active ingredient B is pyraclostrobin, and the mass ratio of the active ingredient A to the active ingredient B is 1:18 to 22:1; The active ingredient B is trifloxystrobin, and the mass ratio of the active ingredient A to the active ingredient B is 1:18 to 15:

1.

4. The bactericidal composition according to claim 3, characterized in that The active ingredient B is pyraclostrobin, and the mass ratio of the active ingredient A to the active ingredient B is 1:15 to 20:1; The active ingredient B is trifloxystrobin, and the mass ratio of the active ingredient A to the active ingredient B is 1:15 to 10:

1.

5. The bactericidal composition according to claim 1, characterized in that The total weight of the bactericidal composition is 100 wt %, and the sum of the contents of the active ingredient A and the active ingredient B in the bactericidal composition is 1 to 80 wt %, preferably 2 to 70 wt %.

6. The bactericidal composition according to claim 1, characterized in that The bactericidal composition includes auxiliary ingredients in addition to active ingredients, and the auxiliary ingredients include one or more of wetting agents, dispersants, emulsifiers, thickeners, disintegrants, antifreeze agents, defoaming agents, solvents, stabilizers, film formers, warning colors, penetrants and carriers.

7. The bactericidal composition according to claim 1, characterized in that The bactericidal composition can be prepared into a solid preparation or liquid preparation dosage form permitted in agriculture; The solid preparation is a water-dispersible granule, a wettable powder or a granule, and the liquid preparation is a suspension, an aqueous emulsion, an emulsifiable concentrate, a microemulsion, a seed treatment suspension, a microcapsule suspension or a dispersible oil suspension.

8. Use of the bactericidal composition according to any one of claims 1 to 7 in controlling pathogenic bacteria in agriculture, forestry or horticulture plants.

9. The use according to claim 8, characterized in that The plant pathogenic bacteria include Botrytis cinerea, Pyricularia oryae, Fusarium moniliforrme, Fusarium graminearum, Rhizoctonia solani and / or Blumeria graminis f.sp.tritici. Preferably, the plant pathogenic bacteria are Fusarium graminearum and Pyricularia oryae.

10. The use according to claim 8, characterized in that The fungicidal composition is applied in an effective amount to plant pathogenic bacteria and / or their environment, or to plants, plant parts, plant propagation materials and subsequently grown plant organs, soil or cultivation media, and materials.

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