Bactericidal composition and application thereof

Abstract

The invention belongs to the technical field of pesticides, and discloses a bactericidal composition and application thereof.The bactericidal composition comprises an active component A and an active component B. The active component A is a compound shown in the formula I: # imgabs0, the active component B is selected from any one of isofluryram, fluoride ether bacteria amide and flutolanil, and the mass ratio of the active component A to the active component B is 1: 35-32: 1. The bactericidal composition disclosed by the invention has a remarkable synergistic effect on various agricultural plant diseases, is excellent in fast-acting property and long in lasting period, can delay the generation of drug resistance of pathogenic bacteria, and is suitable for comprehensive treatment of various agricultural plant diseases.

Description

Technical Field

[0001] The present invention relates to the technical field of pesticide bactericidal, and particularly relates to a bactericidal composition and its use. Background Art

[0002] Isoflucypram is a succinate dehydrogenase inhibitor (SDHI) fungicide with a CAS registration number: 1255734-28-1 and a chemical name: N-[(5-chloro-2-propan-2-ylphenyl)methyl]-N-cyclopropyl-3-(difluoromethyl)-5-fluoro-1-methylpyrazole-4-carboxamide. It can be used to control various diseases such as net blotch, leaf spot, leaf rust, stripe rust, leaf blight, etc. with good control effects.

[0003] Fluxapyroxad, CAS registration number: 1309859-39-9, chemical name: N-((3-chloro-5-(trifluoromethyl)pyridin-2-yl)methyl)-2,3,5,6-tetrafluoro-4-methoxybenzamide. Fluxapyroxad mainly acts on the respiratory chain of fungal mitochondria, can inhibit the activity of succinate dehydrogenase, thereby affecting the electron transfer in mitochondria, hindering its respiration, and inhibiting fungal spore germination, germ tube elongation, hyphal growth and spore mother cell formation.

[0004] Flutolanil, CAS registration number: 66332-96-5, chemical name: N-(3-propan-2-yloxyphenyl)-2-(trifluoromethyl)benzamide; Flutolanil acts as a succinate dehydrogenase inhibitor in the electron transport chain of respiration, inhibits the synthesis of glutamate and aspartate, and is a systemic fungicide with both protective and therapeutic effects, mainly used to control damping-off, sheath blight, southern blight, rust, etc.

[0005] Succinate dehydrogenase inhibitor (SDHI) fungicides act on the succinate dehydrogenase of the pathogen fungal respiratory chain, block electron transfer and interfere with fungal energy metabolism to play a bactericidal role. However, due to the single action site of SDHI fungicides and their large amount of use in agricultural production, the resistance problem is becoming increasingly prominent. Resistant strains have emerged in the field, resulting in reduced field efficacy and increased field application rates. In order to delay the occurrence and development of resistance and improve the control effect of field diseases, the inventor selected a compound of formula I with a different action mechanism from SDHI fungicides, and rationally compounded it with SDHI fungicides. While improving the control effect, the control spectrum was expanded and the generation of pathogen resistance was delayed. Summary of the Invention

[0006] Based on the above situation, the object of the present invention is to provide a bactericidal composition which is effective against a variety of plant pathogenic bacteria, can significantly enhance the efficacy, is superior to single agents in terms of quick-acting and long-lasting effects, reduces the dosage of pesticides in agricultural production, slows down the development of pathogenic bacteria resistance, reduces pesticide residues in agricultural products, and is applicable to the comprehensive management of various diseases in agriculture.

[0007] To achieve the above object, the present invention adopts the following technical scheme: A bactericidal composition, the bactericidal composition contains active ingredient A and active ingredient B, and the active ingredient A is a compound of formula I: The active ingredient B is selected from any one of isoflucypram, fluxapyroxad, and flutolanil, and the mass ratio of the active ingredient A to the active ingredient B is 1:35 to 32:1, or any value within the above numerical range.

[0008] Further, the active ingredient B is isoflucypram, and the mass ratio of the active ingredient A to the active ingredient B is 1:32 to 20:1, or any value within the above numerical range;

[0009] The active ingredient B is fluxapyroxad, and the mass ratio of the active ingredient A to the active ingredient B is 1:35 to 20:1, or any value within the above numerical range;

[0010] The active ingredient B is flutolanil, and the mass ratio of the active ingredient A to the active ingredient B is 1:20 to 30:1, or any value within the above numerical range;

[0011] Further, the active ingredient B is isoflucypram, and the mass ratio of the active ingredient A to the active ingredient B is 1:25 to 15:1, or any value within the above numerical range;

[0012] The active ingredient B is fluxapyroxad, and the mass ratio of the active ingredient A to the active ingredient B is 1:22 to 15:1, or any value within the above numerical range;

[0013] The active ingredient B is flutolanil, 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.

[0014] Further, the active ingredient B is isoflucypram, and the mass ratio of the active ingredient A to the active ingredient B is 1:18 to 10:1, or any value within the above numerical range;

[0015] The active ingredient B is fluxapyroxad, and the mass ratio of the active ingredient A to the active ingredient B is 1:16 to 10:1, or any value within the above numerical range;

[0016] The active ingredient B is flutolanil, and the mass ratio of the active ingredient A to the active ingredient B is 1:5 to 18:1, or any value within the above numerical range.

[0017] Furthermore, based on 100 wt% of the total weight of the bactericidal composition, the total weight of the active ingredient A and the active ingredient B accounts for 1% to 80% of the total weight of the bactericidal composition.

[0018] Furthermore, in addition to the active ingredients, the bactericidal composition also includes other auxiliary ingredients, and the auxiliary ingredients are selected from one or more of wetting agents, dispersants, emulsifiers, thickeners, disintegrants, antifreezing agents, defoaming agents, solvents, preservatives, stabilizers, warning colors, film-forming agents, synergists, and carriers.

[0019] Furthermore, the bactericidal composition can be prepared into any preparation dosage form acceptable in agriculture, and the preparation dosage form is a solid preparation or a liquid preparation;

[0020] Furthermore, the bactericidal composition can be prepared into any preparation dosage form acceptable in agriculture, and the preparation dosage form is a solid preparation, a liquid preparation, and / or a seed treatment preparation;

[0021] Furthermore, the solid preparation is a directly used solid preparation, a dispersible solid preparation, or a soluble solid preparation;

[0022] Furthermore, the directly used solid preparation is a powder, a granule, a ball, a tablet, or a strip;

[0023] The dispersible solid preparation is a wettable powder, an oil-dispersible powder, an emulsion powder, a water-dispersible granule, an emulsion granule, or a water-dispersible tablet;

[0024] The soluble solid preparation is a soluble powder, a soluble tablet, or a soluble granule;

[0025] Furthermore, the liquid preparation is a solution preparation, a dispersion liquid preparation, an emulsion preparation, a suspension preparation, or a multiphase preparation;

[0026] Furthermore, the solution preparation is a soluble solution, a soluble sol, an oil preparation, or a film-forming oil preparation;

[0027] The dispersion liquid preparation is an emulsifiable concentrate, a latex, a dispersible liquid preparation, or an ointment;

[0028] The emulsion preparation is a water-in-oil emulsion, an oil-in-water emulsion, a microemulsion, or a lipid preparation;

[0029] The suspension preparation is a suspending agent, a microcapsule suspension, an oil suspension, or a dispersible oil suspension;

[0030] The multiphase preparation is a suspo-emulsion, a microcapsule suspension-suspension agent, a microcapsule suspension-emulsion in water agent or a microcapsule suspension-suspo-emulsion;

[0031] The solid preparation is a water dispersible granule and / or a wettable powder, and the liquid preparation is a suspending agent.

[0032] The present invention also discloses the use of the bactericidal composition as described above in preventing or controlling crop diseases.

[0033] Furthermore, the crops are selected from food crops, cash crops, fruits and vegetables and / or lawn and garden crops;

[0034] The diseases are sheath blight of wheat, wheat rust, soybean rust, bakanae disease of rice, sheath blight of rice, damping-off of rice, damping-off of cucumber, late blight of potato, downy mildew of cucumber, downy mildew of grape, powdery mildew of wheat, powdery mildew of cucumber, anthracnose of cucumber.

[0035] Still further, the diseases are sheath blight of rice, sheath blight of wheat or downy mildew of cucumber.

[0036] The present invention also discloses a method for preventing and controlling crop pathogenic bacteria, and applying the bactericidal composition and / or its preparation in an effective and substantially non-phytotoxic amount to plants, plant propagation materials and subsequently grown plant organs, cultivation media, materials or spaces by means of seed treatment, foliar application, stem application, soaking, drip irrigation, pouring, spraying, atomizing, dusting, spreading or smoking, etc.

[0037] Compared with the prior art, the advantages of the present invention are as follows:

[0038] 1) The bactericidal composition of the present invention rationally combines compounds with different action mechanisms and has a significant synergistic effect, improves the activity against pathogenic bacteria, improves the field control effect, and is beneficial to delaying the development of drug resistance of pathogenic bacteria;

[0039] 2) The bactericidal composition of the present invention reduces the usage amount of medicaments in agricultural production, reduces the medicament residues in agricultural products, is environmentally friendly, and is beneficial to the comprehensive management of agricultural diseases. Detailed implementation manners

[0040] In order to better understand the essence of the present invention, the content of the present invention will be further described below in conjunction with embodiments, but it cannot be regarded as a limitation to the present invention. The content mentioned in the embodiments is not a limitation to the present invention, and the selection of material formulations can be adjusted according to local conditions without substantial influence on the results.

[0041] Formulation preparation examples:

[0042] Preparation Example 1: 26% Compound of Formula I · isoflucypram suspending agent (1:12)

[0043] By weight percentage, 2% of Compound I, 24% of isoflucypram, 2% of sodium dodecyl sulfate, 1% of ethylene glycol oxyethylene polyoxypropylene ether, 4% of triphenylvinylphenol polyoxyethylene ether phosphate salt, 0.25% of xanthan gum, 1% of magnesium aluminum silicate, 5% of ethylene glycol, 1% of sodium sorbate, 0.5% of silicone oil, and deionized water to make up the balance.

[0044] Preparation method: According to the formula ratio, the active ingredient, surfactant and other functional aids are sequentially placed in a reaction kettle, mixed with water evenly, subjected to high-speed shearing and wet grinding, and finally homogenized and filtered to obtain the suspension product.

[0045] Preparation Example 2: 24% Compound I · isoflucypram water dispersible granule (1:5)

[0046] By weight percentage, 4% of Compound I, 20% of isoflucypram, 5% of naphthalene sulfonate formaldehyde condensate, 10% of sodium lignosulfonate, 4% of Nekal BX, 5% of white sugar, and kaolin to make up the balance.

[0047] Preparation method: According to the formula ratio of the example, the active ingredient is added to the carrier, and a surfactant and other functional aids are added thereto, mixed, 10 - 25% of water is added after air flow pulverization, and then kneaded, granulated, dried and sieved to obtain the water dispersible granule product; or the pulverized powder is sprayed with water, granulated and dried in a fluidized granulator, and then sieved to obtain the product.

[0048] Preparation Example 3: 33% Compound I · isoflucypram wettable powder (10:1)

[0049] By weight percentage, 30% of Compound I, 3% of isoflucypram, 10% of succinate sulfonate, 3% of calcium lignosulfonate, 2% of sodium lignosulfonate, 3% of sodium dodecyl sulfate, 10% of white carbon black, and kaolin to make up the balance.

[0050] Preparation method: According to the formula ratio, the active ingredient, dispersant, wetting agent and filler are mixed, stirred evenly in a stirring kettle, and pulverized and mixed evenly by an air flow pulverizer for multiple times to obtain the wettable powder of the composition of the present invention.

[0051] Preparation Example 4: 20% Compound I · fluxapyroxad suspension (2:3)

[0052] By weight percentage, 8% of Compound I, 12% of fluxapyroxad, 2% of sorbitan oleate polyoxyethylene ether, 3% of arylphenol polyoxyethylene ether phosphate, 2% of sodium lignosulfonate, 0.25% of xanthan gum, 1.5% of magnesium aluminum silicate, 5% of propylene glycol, 0.5% of silicone oil, 0.01% of isothiazolinone, and deionized water to make up the balance;

[0053] Preparation method: the same as Preparation Example 1.

[0054] Preparation Example 5: 36% Compound I·fluxapyroxad water dispersible granules (1:8)

[0055] By weight percentage, 4% of Compound I, 32% of fluxapyroxad, 1.5% of sodium dodecyl sulfate, 5% of polycarboxylate salt, 10% of naphthalene sulfonate formaldehyde condensate, 12% of ammonium sulfate, and starch to make up the balance;

[0056] Preparation method: the same as Preparation Example 2.

[0057] Preparation Example 6: 30% Compound I·fluxapyroxad wettable powder (5:1)

[0058] By weight percentage, 25% of Compound I, 5% of fluxapyroxad, 3% of polycarboxylate salt, 5% of naphthalene sulfonate formaldehyde condensate, 5% of dispersant NNO, 2% of sodium dodecyl sulfate, and kaolin to make up the balance;

[0059] Preparation method: the same as Preparation Example 3.

[0060] Preparation Example 7: 16% Compound I·flutolanil suspension concentrate (1:15)

[0061] By weight percentage, 1% of Compound I, 15% of flutolanil, 2% of alkylaryl polyoxyethylene polyoxypropylene ether, 1% of naphthalene sulfonate formaldehyde condensate, 5% of arylphenol polyoxyethylene ether phosphate, 0.2% of xanthan gum, 1% of magnesium aluminum silicate, 5% of ethylene glycol, 0.1% of sodium benzoate, 0.25% of silicone oil, and deionized water to make up the balance;

[0062] Preparation method: the same as Preparation Example 1.

[0063] Preparation Example 8: 39% Compound I·flutolanil water dispersible granules (12:1)

[0064] By weight percentage, 36% of Compound I, 3% of flutolanil, 8% of lignosulfonate, 5% of naphthalene sulfonate formaldehyde condensate, 2% of fatty alcohol polyoxyethylene ether sulfate, 5% of white carbon black, 30% of starch, and kaolin to make up the balance;

[0065] Preparation method: the same as Preparation Example 2.

[0066] Preparation Example 9: 28% Wettable Powder of Compound of Formula I · Flutolanil (3:1)

[0067] By weight percentage, 21% of the compound of Formula I, 7% of flutolanil, 2% of sodium lignosulfonate, 5% of fatty alcohol polyoxyethylene ether sulfate, 3% of Nekal BX, 5% of silica white, and kaolin to make up the balance;

[0068] Preparation method: The same as Preparation Example 3.

[0069] Indoor Activity Determination Test:

[0070] Example 1: Indoor Activity Determination Test on the Compound of Formula I and Isoflucypram against Sharp Eyespot of Wheat

[0071] Test basis: The test refers to the Agricultural Industry Standard of the People's Republic of China NY / T 1156.2 - 2006 "Guidelines for Pesticide Bioassay in the Laboratory - Part 2: Petri Dish Method for Inhibiting the Mycelial Growth of Pathogenic Fungi".

[0072] Test strain: Rhizoctonia cerealis

[0073] Test material preparation: Transfer the pathogenic bacteria stored in the refrigerator to a PDA medium plate and culture for 2 days at (26 ± 2) °C for standby.

[0074] Test agents: Technical material of the compound of Formula I, technical material of isoflucypram

[0075] Preparation of stock solutions of agents: Dissolve the above technical materials with appropriate solvents to make high - concentration stock solutions, and then dilute with 0.1% Tween 80 aqueous solution. Prepare single - agent stock solutions respectively, and design different ratios according to the purpose of mixing and the activity of the agents. Each single - agent and each mixture of ratios are configured into the required series of mass concentrations.

[0076] Test repetition: For each concentration of the test agents, 4 petri dishes are used, 1 petri dish for each repetition, with a total of 4 repetitions. Use 0.1% Tween 80 aqueous solution without the agent as the blank control.

[0077] Agent treatment: Under aseptic operation conditions, use a pipette to add 5 mL of liquid medicine with different concentrations to pre - calibrated sterile Erlenmeyer flasks respectively, and then add the medium melted and cooled to an appropriate temperature to the Erlenmeyer flasks. After shaking well, pour an equal amount into 4 petri dishes to make the corresponding concentration of PDA plates containing the agent.

[0078] Inoculation: Cut the mycelial cake from the edge of the pre - cultured Rhizoctonia cerealis colony under aseptic conditions, and use an inoculator to inoculate the mycelial cake in the center of the agent - containing plate. Cover the lid and place it in a constant - temperature incubator at 25 °C for dark culture.

[0079] Data investigation: Conduct experimental investigations when the colonies in the control treatment grow to 2 / 3 to 4 / 5 of the diameter of the culture dish. Measure the diameter of the colonies (cm) with a ruler. Measure the diameter of each colony once using the cross method and take the average value.

[0080] Data statistics and analysis: According to the investigation results, calculate the mycelial growth inhibition rate of each treatment concentration on the test target bacteria, and calculate the result as a percentage (%). Keep two decimal places after the decimal point.

[0081] D = D1 - D2

[0082] In the formula:

[0083] D —— Colony growth diameter;

[0084] D1 —— Colony diameter;

[0085] D2 —— Mycelial disc diameter.

[0086]

[0087] In the formula:

[0088] I —— Mycelial growth inhibition rate;

[0089] D0 —— Colony growth diameter of the blank control;

[0090] D T —— Colony growth diameter of the medicament treatment.

[0091] Use the statistical analysis system for analysis to obtain the toxicity regression line and EC 50 value, and evaluate the activity of the test medicament on the biological test materials.

[0092] Sun Yunpei method: Evaluate the synergistic effect of medicament mixtures according to the co-toxicity coefficient (CTC). When the co-toxicity coefficient CTC of the mixture is ≥ 120, it shows a synergistic effect; when CTC ≤ 80, it shows an antagonistic effect; when 80 < CTC < 120, it shows an additive effect.

[0093] The co-toxicity coefficient (CTC value) of the mixture is calculated according to the following formula:

[0094]

[0095] In the formula:

[0096] ATI —— Measured toxicity index of the mixture;

[0097] S —— EC of the standard medicament 50 , in milligrams per liter (mg / L);

[0098] M —— EC of the mixture 50, in milligrams per liter (mg / L).

[0099] TTI = TI A ×P A +TI B ×P B

[0100] Where:

[0101] TTI—theoretical toxicity index of the mixture;

[0102] TI A —toxicity index of chemical A;

[0103] P A —percentage content of chemical A in the mixture, in percentage (%);

[0104] TI B —toxicity index of chemical B;

[0105] P B —percentage content of chemical B in the mixture, in percentage (%).

[0106]

[0107] Where:

[0108] CTC—coefficient of co-toxicity;

[0109] ATI—actual toxicity index of the mixture;

[0110] TTI—theoretical toxicity index of the mixture.

[0111] The test results are shown in the following table:

[0112] Table 1 Test results of the indoor activity determination of the compound of Formula I and isoflucypram against Rhizoctonia cerealis

[0113]

[0114] From the test results in Table 1, it can be seen that the tested chemicals, the compound of Formula I and isoflucypram, have good control effects on the pathogen of Rhizoctonia cerealis, and their EC 50They are 0.2196 mg / L and 1.6540 mg / L respectively. When the mass ratio of the compound of formula I to isoflucypram is in the range of 1:32 to 20:1, the co-toxicity coefficient is greater than 120, showing a synergistic effect on Rhizoctonia cerealis; when the mass ratio of the compound of formula I to isoflucypram is in the range of 1:25 to 15:1, the co-toxicity coefficient is greater than 130, and the synergistic effect is obvious; when the mass ratio of the compound of formula I to isoflucypram is in the range of 1:18 to 5:1, the co-toxicity coefficient is greater than 150, and the synergistic effect on Rhizoctonia cerealis is significant; among them, when the compound of formula I and isoflucypram are compounded according to the mass ratio of 1:5, the co-toxicity coefficient is the largest and the synergistic effect is the most significant.

[0115] Example 2: Indoor bioassay of the compound of formula I and fluopicolide against Pseudoperonospora cubensis

[0116] Test basis: The test was carried out with reference to NY / T 1156.7-2006 "Pesticide Bioassay Guidelines for Indoor Fungicides Part 7: Test of Control of Pseudoperonospora cubensis by Potted Plant Method".

[0117] Test target: Pseudoperonospora cubensis

[0118] Test instruments and equipment: electronic balance, spraying equipment, artificial climate chamber, biological incubator, culture dish, pipette, etc.

[0119] Test material preparation: Select the susceptible cucumber variety (Xintaimici) for potting, and reserve the seedlings when they grow to 4 - 6 true leaf stage.

[0120] Test agents: The technical material of the compound of formula I, the technical material of fluopicolide.

[0121] Test steps:

[0122] Select the diseased cucumber leaves, wash the sporangia of Pseudoperonospora cubensis on the back of the leaves with distilled water at 4°C, prepare a suspension, and store it at 4°C for later use. Dissolve the technical material with a suitable solvent and then dilute it with 0.1% Tween 80 aqueous solution. According to the activity of the agent, set 5 series of mass concentrations, spray the fresh sporangia suspension on the back of the leaves for inoculation, 5 pots for each treatment, 2 plants for each pot, and repeat each treatment 4 times. Apply the medicine 24 h after inoculation. According to the test design, evenly spray the agents of each treatment on both sides of the leaves until they are all wet. Set a treatment without agent as the blank control. After applying the medicine, culture it under the conditions of a photoperiod of light:dark = 12 h:12 h, a temperature of 17 - 22°C, and a relative humidity of 90% - 95%. According to the disease incidence of the blank control, conduct a grading survey on the inoculated leaves. Investigate 30 leaves for each treatment.

[0123] The following grading method is used for grading investigation and recording:

[0124] Grade 0: Disease-free;

[0125] Grade 1: The diseased area accounts for less than 5% of the entire leaf area;

[0126] Grade 3: The diseased area accounts for 6% - 10% of the entire leaf area;

[0127] Grade 5: The diseased area accounts for 11% - 25% of the entire leaf area;

[0128] Grade 7: The diseased area accounts for 26% - 50% of the entire leaf area;

[0129] Grade 9: The diseased area accounts for more than 50% of the entire leaf area;

[0130] Data calculation:

[0131] Based on the data investigation, calculate the disease index and control effect of each treatment.

[0132] The disease index is calculated according to the following formula:

[0133]

[0134] The control effect is calculated according to the following formula:

[0135]

[0136] Statistical analysis:

[0137] Use the statistical analysis system for analysis to obtain the EC 50 value and evaluate the activity of the test agents on the biological test materials.

[0138] The co-toxicity coefficient (CTC value) of the mixture is calculated according to the following formula:

[0139]

[0140] In the formula:

[0141] ATI - Measured toxicity index of the mixture;

[0142] S - EC of the standard agent 50 , in milligrams per liter (mg / L);

[0143] M - EC of the mixture 50 , in milligrams per liter (mg / L).

[0144] TTI = TI A ×P A +TI B ×P B

[0145] In the formula:

[0146] TTI—theoretical toxicity index of the mixture;

[0147] TI A —toxicity index of chemical A;

[0148] P A —percentage content of chemical A in the mixture, in percentage (%);

[0149] TI B —toxicity index of chemical B;

[0150] P B —percentage content of chemical B in the mixture, in percentage (%).

[0151]

[0152] In the formula:

[0153] CTC—coefficient of co-toxicity;

[0154] ATI—measured toxicity index of the mixture;

[0155] TTI—theoretical toxicity index of the mixture.

[0156] When the coefficient of co-toxicity CTC of the compounding ≥ 120, it shows a synergistic effect; when CTC ≤ 80, it shows an antagonistic effect; when 80 < CTC < 120, it shows an additive effect.

[0157] The results of the indoor test are shown in the following table:

[0158] Table 2 Test results of indoor activity determination of the compounding of Compound I and fluxapyroxad against Pseudoperonospora cubensis

[0159]

[0160] It can be seen from the test results in Table 2 that the tested chemicals, Compound I and fluxapyroxad, have good therapeutic effects against Pseudoperonospora cubensis. Their EC 50 are 6.2910 mg / L and 15.5076 mg / L respectively. When the mass ratio of Compound I to fluxapyroxad is in the range of 1:35 to 20:1, their coefficients of co-toxicity are all greater than 120, showing a synergistic effect against Pseudoperonospora cubensis; when the mass ratio of Compound I to fluxapyroxad is in the range of 1:22 to 15:1, their coefficients of co-toxicity are all greater than 130, with an obvious synergistic effect; when the mass ratio of Compound I to fluxapyroxad is in the range of 1:16 to 10:1, their coefficients of co-toxicity are all greater than 150, with a significant synergistic effect against Pseudoperonospora cubensis; among them, when Compound I and fluxapyroxad are compounded at a mass ratio of 2:3, the coefficient of co-toxicity is the largest and the synergistic effect is the most significant.

[0161] Example 3: Indoor Activity Determination Test of Compound of Formula I and Flutolanil against Rhizoctonia solani

[0162] Test Basis: The test refers to the Agricultural Industry Standard of the People's Republic of China NY / T 1156.2 - 2006 "Pesticide Bioassay Guidelines for Indoor Fungicides - Part 2: Petri Dish Method for Inhibiting Mycelial Growth of Pathogenic Fungi".

[0163] Test Target: Rhizoctonia solani

[0164] Instrument and Equipment: Autoclave, Laminar Flow Hood, Constant Temperature and Light Incubator, Electrothermal Drum Wind-proof Drying Oven, Ten-thousandth Electronic Balance, Pipette, Alcohol Lamp, Small Beaker, Volumetric Flask, Erlenmeyer Flask, Petri Dish, Puncher, Inoculator, Ruler, etc.

[0165] Cultivation Conditions of Test Target: Transfer the Rhizoctonia solani preserved in the indoor refrigerator to the Potato Dextrose Agar Medium, place it in the incubator at 26°C for dark cultivation for 4 days to activate it, and set aside for use.

[0166] Test Agents: Compound of Formula I and Flutolanil Technical

[0167] Preparation of Medicament Stock Solution: Dissolve the above technicals with appropriate solvents respectively to make high-concentration stock solutions, and then dilute them with 0.1% Tween 80 aqueous solution to prepare single-agent stock solutions respectively. Design different ratios according to the purpose of mixing and the activity of the medicaments, and configure each single-agent and the mixed agents of each group into the required series of mass concentrations.

[0168] Test Repetition: For each concentration of the test medicaments, 4 petri dishes are used, 1 petri dish for each repetition, with a total of 4 repetitions. Use 0.1% Tween 80 aqueous solution without medicament as the blank control.

[0169] Medicament Treatment: Under aseptic operation conditions, quantitatively add the pre-melted and sterilized PDA medium to a sterile conical flask according to the test treatment. Sequentially and quantitatively pipette 10 mL of the prepared treatment solutions of each concentration from low to high, and add them to the above conical flasks respectively. Shake well, and then pour them equally into 4 petri dishes with a diameter of 9 cm to make drug-containing plates of corresponding concentrations.

[0170] Inoculation: Cut a mycelial cake from the edge of the pre-cultured Rhizoctonia solani colony, and use an inoculator to inoculate the mycelial cake in the center of the drug-containing plate. Cover the lid and place it in a constant temperature and light incubator at (25 ± 1)°C for dark cultivation.

[0171] Data investigation: Investigate the growth of pathogenic hyphae based on the growth of hyphae in blank control petri dishes. Measure the colony diameter with a ruler 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.

[0172] Data statistics and analysis: According to the investigation results, calculate the inhibition rate of mycelial growth of the tested target bacteria for each treatment concentration, expressed as a percentage (%). Round the calculation results to two decimal places.

[0173] D = D1 - D2

[0174] Where:

[0175] D - Colony growth diameter;

[0176] D1 - Colony diameter;

[0177] D2 - Disc diameter.

[0178]

[0179] Where:

[0180] I - Inhibition rate of mycelial growth;

[0181] D0 - Colony growth diameter of blank control;

[0182] D T - Colony growth diameter of medicament treatment.

[0183] Use the method of probit analysis to process the data. Analyze with the statistical analysis system to obtain the toxicity regression line, EC 50 value and correlation coefficient R 2 , and evaluate the activity of the tested medicaments on biological test materials.

[0184] Sun Yunpei method: Evaluate the synergistic effect of medicament mixtures according to the co-toxicity coefficient (CTC). A co-toxicity coefficient CTC ≥ 120 for the mixture indicates a synergistic effect; CTC ≤ 80 indicates an antagonistic effect; 80 < CTC < 120 indicates an additive effect.

[0185] The co-toxicity coefficient (CTC value) of the mixture is calculated according to the following formula:

[0186]

[0187] Where:

[0188] ATI - Measured toxicity index of the mixture;

[0189] S - EC of the standard medicament 50 , in milligrams per liter (mg / L);

[0190] M - EC of the mixture 50 , in milligrams per liter (mg / L).

[0191] TTI = TI A ×P A +TI B ×P B

[0192] Wherein:

[0193] TTI - Theoretical toxicity index of the mixture;

[0194] TI A - Toxicity index of agent A;

[0195] P A - Percentage content of agent A in the mixture, in percentage (%);

[0196] TI B - Toxicity index of agent B;

[0197] P B - Percentage content of agent B in the mixture, in percentage (%).

[0198]

[0199] Wherein:

[0200] CTC - Co - toxicity coefficient;

[0201] ATI - Measured toxicity index of the mixture;

[0202] TTI - Theoretical toxicity index of the mixture.

[0203] The test results are shown in the following table:

[0204] Table 3 Test results of indoor activity determination of the compound of Formula I and flutolanil in combination against Rhizoctonia solani on rice

[0205]

[0206] It can be seen from the test results in Table 3 that the tested agents, the compound of Formula I and flutolanil, have good control effects on the pathogen of Rhizoctonia solani on rice, and their EC 50They are 0.5567 mg / L and 0.2694 mg / L respectively. When the mass ratio of the compound of Formula I to flutolanil is in the range of 1:20 to 30:1, the co-toxicity coefficient is greater than 120, showing a synergistic effect on rice sheath blight; when the mass ratio of the compound of Formula I to flutolanil is in the range of 1:15 to 20:1, the co-toxicity coefficient is greater than 130, showing an obvious synergistic effect on rice sheath blight; when the mass ratio of the compound of Formula I to flutolanil is in the range of 1:5 to 18:1, the co-toxicity coefficient is greater than 150, showing a significant synergistic effect on rice sheath blight; among them, when the compound of Formula I and flutolanil are compounded according to the mass ratio of 3:1, the co-toxicity coefficient is the largest and the synergistic effect is the most significant.

[0207] Field efficacy test:

[0208] Example 4: Field efficacy test for controlling wheat sheath blight

[0209] Test site: Wheat field in Sunjiashangou Village, Yanjiazhuang Town, Juxian County, Shandong Province. The soil of the test plot is fluvo-aquic cinnamon soil formed by diluvial alluvium, with medium to high soil fertility. Wheat sheath blight has occurred generally and evenly over the years.

[0210] Test target: Wheat sheath blight.

[0211] Test crop: Wheat (Luyuan 502).

[0212] Test design: The test was set with 8 treatments in total. The dosage of each treatment is shown in the following table, and spraying clear water was used as the control (CK). There were 4 replicates, a total of 32 plots. The plots were arranged in a randomized block design, and the plot area was 72 m 2 .

[0213] Application time: The test was applied once at the late jointing stage of wheat. An agricultural - 16 knapsack sprayer was used to conduct conventional manual spraying on the whole wheat plant.

[0214] Test investigation: 5 points were randomly determined in each plot, with 50 plants at each point. The disease incidence was investigated 25 days after application. The disease incidence was investigated according to the following grading standard, and the disease index and control effect were calculated.

[0215] Grading standard:

[0216] Grade 0, no disease;

[0217] Grade 1, the leaf sheath is diseased but the stem is not diseased;

[0218] Grade 3, the leaf sheath is diseased and the disease has invaded the stem, but the stem lesion rings less than 1 / 2 of the stem;

[0219] Grade 5, the stem lesion rings more than 1 / 2 of the stem, but it does not lodge or break;

[0220] Grade 7, withered, lodged, and white ears.

[0221] Calculation method:

[0222]

[0223] The results of the field efficacy trials are as follows:

[0224] Table 4 Results of the field efficacy trials for controlling wheat sharp eyespot

[0225] Number Name of medicament <![CDATA[Application rate of active ingredient (g / hm 2 )]]> Disease index Control effect (%) 1 Preparation Example 9: 28% Compound of Formula I · fluxapyroxad wettable powder (3:1) 185 1.29 95.16 2 Preparation Example 8: 29% Compound of Formula I · fluxapyroxad water dispersible granule (12:1) 185 3.34 87.41 3 Preparation Example 2: 24% Compound of Formula I · isoflucypram water dispersible granule (1:5) 185 1.81 93.17 4 Preparation Example 1: 26% Compound of Formula I · isoflucypram suspension concentrate (1:12) 185 2.99 88.76 5 25% isoflucypram wettable powder 225 9.06 65.90 6 20% fluxapyroxad water dispersible granule 225 7.46 71.92 7 20% Compound of Formula I suspension concentrate 225 6.17 76.76 8 Blank control / 26.56 /

[0226] At 25 days after application, all 7 fungicides had a certain control effect on wheat sharp eyespot. Preparation Example 9: The 28% Compound of Formula I · fluxapyroxad wettable powder (3:1) had the highest control efficacy, reaching 95.16%; followed by Preparation Example 2: the treatment group of 24% Compound of Formula I · isoflucypram water dispersible granule (1:5), with a control efficacy of 93.17%; compared with the blank control, the compound preparations had a significant control effect on wheat sharp eyespot.

[0227] Example 5: Field efficacy trial for controlling rice sheath blight

[0228] Test basis: The test was carried out with reference to GB / T 17980.20 - 2000 "Pesticide - Guidelines for the field efficacy trials (I) - Fungicides for controlling rice sheath blight".

[0229] Test target: Rice sheath blight (Thanatephorus cucumeris).

[0230] Test crop: Rice (Huai - dao 5).

[0231] Test location: Conducted in Dali Village, Yanlong Sub - district, Yandu District, Yancheng City, Jiangsu Province. The test field was a rice - wheat rotation field with the previous crop being wheat. The soil texture of the test field was clay, with high soil fertility. The management measures within the test area were consistent and in line with local agricultural production practices.

[0232] Test fungicides: The test fungicides and application rates are shown in the following table.

[0233] Test design: The plot treatments were randomly arranged, and the area of each plot was 20 m 2 , and each treatment was replicated 4 times.

[0234] Test implementation: The pesticides were applied twice on August 5, 2024 (late tillering stage of rice) and August 26, 2024 (early booting stage of rice). The test used a 3WBD - 18 type knapsack electric sprayer to spray evenly on the whole plant. The working pressure of the sprayer was 0.15 - 0.40 Mpa, the spray width was 4 - 5 m, and the water consumption per 667 m 2 was 30 kg. Before pesticide application, the field was irrigated with 5 - 7 cm of water and the water was retained for 6 days.

[0235] Investigation method: After each application of the pesticide, the visual inspection method was used to observe the growth and development of rice in each plot irregularly to evaluate the safety of each pesticide on rice growth. The investigation was carried out 8 days after the last application of the pesticide. According to the degree of damage symptoms of rice leaf sheaths and leaves, taking five points along the diagonal of each plot with plants as the unit, investigating 5 adjacent clusters at each point, a total of 25 clusters, and recording the total number of plants, the number of diseased plants and the disease grade.

[0236] Disease grading standard:

[0237] Grade 0: The whole plant is disease-free;

[0238] Grade 1: The fourth leaf and the leaf sheaths and leaves below it are diseased (taking the flag leaf as the first leaf);

[0239] Grade 3: The third leaf and the leaf sheaths and leaves below it are diseased;

[0240] Grade 5: The second leaf and the leaf sheaths and leaves below it are diseased;

[0241] Grade 7: The flag leaf and the leaf sheaths and leaves below it are diseased;

[0242] Grade 9: The whole plant is diseased and withers prematurely.

[0243] Calculation method of pesticide efficacy:

[0244]

[0245] The results of the field pesticide efficacy experiment are shown in the following table:

[0246] Table 5 Results of the field efficacy test for controlling sheath blight of rice

[0247]

[0248] As shown in the test results in Table 5, the control effects of the compound of Formula I and different mixed pesticides with flutolanil or isoflucypram on rice sheath blight are all better than those of the control pesticide. 8 days after the last application, the highest control effect of the bactericidal composition of the present invention reached 92.86%.

[0249] Example 6: Field efficacy test for controlling cucumber downy mildew

[0250] This test was carried out with reference to GB / T 17980.26-2000 "Pesticide field efficacy test guidelines (I) Fungicides for controlling cucumber downy mildew".

[0251] Test site: The test site is located in the greenhouse of Henan Village, Hanting District, Weifang City. The test greenhouse is a solar greenhouse with a relatively flat terrain and sandy loam soil type. Due to the perennial cultivation of cucumbers in this greenhouse, cucumber downy mildew occurs from time to time.

[0252] Test target: Pseudoperonospora cubensis.

[0253] Test crop: Cucumber (Xintaimici).

[0254] Test design: This test was set with 6 treatments in total, including 3 compound agent treatments, 2 single-agent controls, and 1 water control treatment. Each treatment had 4 replicates, and the area of each plot was 15 m 2 , with isolation rows set on both sides and between plots. The cultivation conditions and field cultivation management of each plot were the same.

[0255] Test method: The test was sprayed with medicine 2 times in total. The first spraying time was when sporadic cucumber downy mildew was found in the greenhouse, and the second spraying was carried out after an interval of 7 days. A Hemei brand HM-16A backpack electric sprayer (produced by Zhongshan Hemei Electric Appliance Co., Ltd., with a working pressure of 0.2 - 0.4 MPa) was used to evenly spray the cucumber plants after diluting with water, and the water consumption per mu was 45 kg. When spraying medicine, the front and back sides of the leaves were evenly covered with medicine until they were wet. During the test, the cucumber was in the initial flowering stage to the full fruit-setting stage.

[0256] Test investigation: The control effects were investigated 7 days after the first spraying and 10 days after the second spraying, with a total of 2 investigations. During the investigation, the 5-point sampling method was used in each plot. 2 plants were investigated at each point, with a total of 10 plants, and all the leaves of each plant were investigated. The percentage of the diseased area of each leaf in the total leaf area was used for grading, and the number of diseased leaves in each treatment was recorded respectively, and the disease index and control effect were calculated.

[0257] During the whole test process, the safety of each agent treatment on cucumbers was observed irregularly, and no adverse effects of the tested agents on cucumbers were found.

[0258] Grading method:

[0259] Grade 0, no disease spots;

[0260] Grade 1, the diseased area accounts for less than 5% of the total leaf area;

[0261] Grade 3, the diseased area accounts for 6% - 10% of the total leaf area;

[0262] Grade 5, the diseased area accounts for 11% - 25% of the total leaf area;

[0263] Grade 7, the diseased area accounts for 26% - 50% of the total leaf area;

[0264] Grade 9, the diseased area accounts for more than 51% of the total leaf area.

[0265] The disease index and control effect were calculated according to the following formulas:

[0266]

[0267] The results of the field efficacy trials are shown in the following table:

[0268] Table 6 Results of the field efficacy trials for controlling Pseudoperonospora cubensis

[0269]

[0270] The field efficacy trials showed (Table 6) that for Preparation Example 6: 30% wettable powder of Compound of Formula I · fluopyram (5:1), Preparation Example 4: 20% suspension concentrate of Compound of Formula I · fluopyram (2:3), and Preparation Example 5: 36% water dispersible granules of Compound of Formula I · fluopyram (1:8), the control efficacy was 87% - 92% 10 days after the second application. Therefore, the reasonable compounding of the Compound of Formula I and fluopyram has a good control effect on Pseudoperonospora cubensis, and can effectively slow down the spread of the disease.

[0271] It can be seen from the indoor toxicity tests and field efficacy trials that the bactericidal composition of the present invention shows a good control effect against pathogenic bacteria of the genus Fusarium, is safe for crops, delays the generation of drug resistance of pathogenic bacteria, reduces the dosage of the medicament, and at the same time reduces the medicament residues in agricultural products.

[0272] Although the present invention has been described in detail above with general descriptions and specific embodiments, based on the present invention, some modifications or improvements can be made, which are obvious to those skilled in the art. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection required by the present invention.

Claims

1. A bactericidal composition, characterized in that, The described bactericidal composition contains active ingredient A and active ingredient B. The active ingredient A is a compound of formula I: The active ingredient B is selected from any one of isoflucypram, fluxapyroxad, and flutolanil. The mass ratio of the active ingredient A to the active ingredient B is 1:35 to 32:

1.

2. The bactericidal composition according to claim 1, wherein The active ingredient B is isoflucypram, and the mass ratio of the active ingredient A to the active ingredient B is 1:32 to 20:1; The active ingredient B is fluxapyroxad, and the mass ratio of the active ingredient A to the active ingredient B is 1:35 to 20:1; The active ingredient B is flutolanil, and the mass ratio of the active ingredient A to the active ingredient B is 1:20 to 30:

1.

3. The bactericidal composition according to claim 2, wherein The active ingredient B is isoflucypram, and the mass ratio of the active ingredient A to the active ingredient B is 1:25 to 15:1; The active ingredient B is fluxapyroxad, and the mass ratio of the active ingredient A to the active ingredient B is 1:22 to 15:1; The active ingredient B is flutolanil, and the mass ratio of the active ingredient A to the active ingredient B is 1:15 to 20:

1.

4. The bactericidal composition according to claim 3, characterized in that, The active ingredient B is isoflucypram, and the mass ratio of the active ingredient A to the active ingredient B is 1:18 to 10:1; The active ingredient B is fluxapyroxad, and the mass ratio of the active ingredient A to the active ingredient B is 1:16 to 10:1; The active ingredient B is flutolanil, and the mass ratio of the active ingredient A to the active ingredient B is 1:5 to 18:

1.

5. The bactericidal composition according to claim 1, wherein Based on the total weight of the bactericidal composition being 100 wt%, the total weight of the active ingredient A and the active ingredient B accounts for 1% to 80% of the total weight of the bactericidal composition.

6. The bactericidal composition according to claim 1, characterized in that, The bactericidal composition further includes other auxiliary ingredients in addition to the active ingredients, and the auxiliary ingredients are selected from one or more of wetting agents, dispersants, emulsifiers, thickeners, disintegrants, antifreezing agents, defoaming agents, solvents, preservatives, stabilizers, warning colors, film-forming agents, synergists, and carriers.

7. The bactericidal composition according to claim 1, wherein The bactericidal composition can be prepared into any agriculturally acceptable preparation dosage form, and the preparation dosage form is a solid preparation or a liquid preparation; The solid preparation is a water dispersible granule and / or a wettable powder, and the liquid preparation is a suspension concentrate.

8. Use of the bactericidal composition according to any one of claims 1-7 in preventing or controlling crop diseases.

9. The use according to claim 8, wherein The crops are selected from food crops, cash crops, fruits and vegetables, and / or lawn and garden crops; The diseases are sheath blight of wheat, rust of wheat, rust of soybean, bakanae disease of rice, sheath blight of rice, damping-off of rice, damping-off of cucumber, late blight of potato, downy mildew of cucumber, downy mildew of grape, powdery mildew of wheat, powdery mildew of cucumber, anthracnose of cucumber.

10. A method for preventing and controlling pathogenic bacteria in crops, characterized in that, The bactericidal composition and / or its preparation are applied to plants, plant propagation materials, and subsequently grown plant organs, cultivation media, materials, or spaces in an effective and substantially non-phytotoxic application rate by methods such as seed treatment, foliar application, stem application, soaking, drip irrigation, pouring, spraying, atomizing, dusting, spreading, or fumigating.

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