A compound composition of propane amidine and tetrafluoro-ethazole, a bactericide and application thereof

Abstract

The application provides a compound composition of propane amidine and tetrafluorothiopheneazole, a fungicide and application; the composition comprises propane amidine and tetrafluorothiopheneazole, and the mass ratio of the two is (1-10):(10-1). The compound of propane amidine and tetrafluorothiopheneazole is used for preventing and treating corn large spot, fruit and vegetable and grain powdery mildew, botrytis blight, rice blast and various crop fungal diseases, has obvious synergistic effect, and can significantly reduce the use amount of the pesticide, and the compound preparation has the potential to develop into a new generation of environment-friendly, efficient and low-toxicity agricultural fungicide.

Description

Technical Field

[0001] This invention belongs to the field of agricultural fungicides, specifically relating to a compound composition of propanemid and tetrafluoroether, a fungicide and its application. The combination of these two compounds is used to control corn leaf blight, powdery mildew of fruits, vegetables and grains, gray mold and rice blast. It belongs to the invention of new uses and application technology of fungicides. Background Technology

[0002] Crop diseases caused by pathogens cause serious damage to global food production and result in huge economic losses every year. Currently, the use of chemical fungicides is the main measure for controlling crop diseases. However, the large-scale and repeated use of single chemical pesticides easily leads to pesticide resistance. The purpose of pesticide mixing is mainly to broaden the target pests, reduce the number of applications, utilize synergistic effects, and inhibit or delay resistance development. The rational mixing of pesticides, especially the mixing of pesticides with different mechanisms of action and those that produce significant synergistic effects, is one of the effective measures to delay resistance.

[0003] Propamidine, belonging to the alkylamidine class of compounds, is a novel fungicide developed by the Shaanxi Provincial Engineering Technology Research Center for Biological Pesticides. Previous research by our team has revealed that propamidine possesses broad-spectrum antibacterial activity, along with protective and curative effects. Propamidine is a low-toxicity compound with excellent systemic conduction and both protective and curative properties. It exhibits high toxicity against *Sclerotinia sclerotinia*, *Black spot fungus*, and *Ophiopogon japonicus*, with the strongest toxicity against *Botrytis cinerea*. The raw materials for propamidine are inexpensive, and the synthesis process is simple. Propamidine does not exhibit cross-resistance with existing fungicides, and its antibacterial molecular target is unique.

[0004] Epoxiconazole, developed by the Italian company SEG, is a novel triazole fungicide with a broad spectrum of activity, strong systemic properties, and long-lasting effect. It is particularly effective against various pathogens affecting cereal crops. Epoxiconazole does not interfere with the normal biosynthesis of gibberellins in plants, nor does it inhibit normal crop growth. It can be used at any stage of crop growth, even under high temperature and humidity conditions, without causing phytotoxicity. It is also effective in preventing wheat loose smut, rust, and yellow smut; barley cloud stripe and loose smut; rice blast; corn smut; sorghum smut; banana leaf spot; apple leaf spot; and pear scab. It can be used as a foliar spray or as a seed treatment. Because epoxiconazole is a triazole fungicide with a relatively singular site of action, it is prone to resistance. Therefore, alternating its use with other fungicides with different mechanisms of action, or combining it with other fungicides, is an important way to slow the development and spread of resistance and extend its lifespan. Previous studies by our research group have shown that tetraflufenicol has good antibacterial activity against maize leaf spot pathogens, but tetraflufenicol has not yet been registered for the control of maize leaf spot. Summary of the Invention

[0005] The purpose of this invention is to provide a compound composition of propanemid and tetrafluoroether, a fungicide and its application. The binary compound of propanemid and tetrafluoroether can be used for the prevention and control of corn leaf blight, powdery mildew, gray mold and rice blast.

[0006] To achieve the above objectives, the technical solution adopted by the present invention includes:

[0007] A compound composition of propanemidine and tetrafluoroetherazole, wherein the composition comprises propanemidine and tetrafluoroetherazole in a mass ratio of (1-10):(10-1).

[0008] Optionally, the mass ratio of propanemidine to tetrafluoroetherazole is (1-4):(8-1).

[0009] Optionally, the mass ratio of propanemidine to tetrafluoroetherazole is 1:2.

[0010] The compound composition of propanemidine and tetrafluoroetherazole described in any one of the present invention is used in the preparation of compound bactericides.

[0011] Optionally, the compound fungicide is used to control corn leaf blight, powdery mildew, gray mold, and / or rice blast.

[0012] Optionally, the formulation of the compound bactericide includes suspension concentrate and water-dispersible granules; by mass percentage, propanemid is 1% to 30% and tetrafluoroether is 1% to 40% in the compound bactericide.

[0013] A compound bactericide, wherein the compound bactericide is in the form of a suspension;

[0014] The suspending agent, by weight percentage, comprises the following components:

[0015] Propaneamidine 1%–20%, tetrafluoroether 1%–40%, emulsifier 1%–10%, wetting and dispersing agent 1%–5%, thickener 1%–5%, defoamer 0.15%–4%, antifreeze 1%–5%, preservative 1%–5%, and water to bring the total to 100%.

[0016] Optionally, the emulsifier is an anionic emulsifier or a nonionic emulsifier;

[0017] The wetting and dispersing agent is at least one of alkylphenol resin polyethylene ether, alkylbenzene sulfonate, long-chain fatty alcohol polyoxyethylene ether, alkylphenol polyoxyethylene ether, and fatty alcohol sulfate salt;

[0018] The thickener is polyvinyl alcohol, xanthan gum, sodium alginate, xanthan gum, or hydroxypropyl methylcellulose;

[0019] The defoamer is an acetylenic diol wetting defoamer or an organosilicon defoamer;

[0020] The antifreeze agent is selected from at least one of ethylene glycol, propylene glycol, glycerol, and polyethylene glycol;

[0021] The preservative mentioned is sodium benzoate.

[0022] A compound bactericide, wherein the formulation of the compound bactericide is a water-dispersible granule, and the components and weight percentages of the water-dispersible granule are as follows:

[0023] Propaneamidine 20%–40%, tetrafluoroetherazole 20%–40%, wetting agent 1%–10%, dispersant 1%–10%, disintegrant 1%–5%, binder 0.5%–5%, stabilizer 1%–5%, filler 1%–10%, total 100%.

[0024] Optionally, the wetting agent is a dispersant powder, the dispersant is magnesium aluminum silicate, the disintegrant is starch, the binder is sodium carboxymethyl cellulose, the stabilizer is ascorbic acid, and the filler is kaolin.

[0025] Compared with the prior art, the advantages of the present invention are:

[0026] (1) Through a series of ratio experiments, the present invention found that propanemid and tetrafluoroether have a significant synergistic effect when used in a certain ratio, and can be used to prepare agricultural compound fungicides; propanemid and tetrafluoroether have an additive effect when compounded at a ratio of 1:10 to 10:1, especially at a ratio of 1:2, which shows a significant synergistic effect.

[0027] (2) Further tests on the efficacy of disease control showed that the compound fungicide prepared by propanemid and tetrafluoroether of the present invention has good control effects on corn leaf blight, powdery mildew, gray mold and rice blast. Detailed Implementation

[0028] The following detailed description of the present invention is exemplary and not intended to limit the scope of the invention. Based on the embodiments of the present invention, all non-inventory modifications made by those skilled in the art without departing from the present invention should be considered within the scope of protection of the present invention.

[0029] This invention provides a compound composition of propanemid and tetraflufenicol, a fungicide, and its application; the mass ratio of propanemid to tetraflufenicol is 1:10 to 10:1. The compound of propanemid and tetraflufenicol is used to control various fungal diseases of crops, including corn leaf blight, powdery mildew of fruits, vegetables, and cereals, gray mold, and rice blast. It exhibits a significant synergistic effect and can significantly reduce the amount of pesticide used. This compound formulation has the potential to be developed into a new generation of environmentally friendly, highly efficient, and low-toxic agricultural fungicide.

[0030] Example 1: Determination of the in vitro antibacterial activity of propanemidine and tetrafluoroetherazole

[0031] The antibacterial activities of propanemidin and tetraflufenicol against pathogens were determined using single-dose inhibition rate and mycelial growth rate methods, respectively, for primary and secondary screening. Propanamidine and tetraflufenicol were dissolved in methanol to prepare a series of stock solutions of different concentrations. After the PDA medium cooled to approximately 50°C, 0.2 mL of the stock solutions were mixed with 100 mL / bottle of PDA medium to prepare a series of drug-containing media. After thorough mixing, the media were quickly poured into six 9 cm diameter petri dishes. Once solidified, a 0.5 cm diameter mycelial fragment of the pathogen was placed in the center of the dish (mycelial side down). A blank control was prepared by adding 0.2 mL of methanol. After incubation at 25°C for 6 days, the colony diameter was measured using the cross-sectional method. Using the blank control as the standard, the inhibition rate was calculated using the following formula, and the effective inhibitory concentration (EC50) was calculated. 50 Value, in μg / mL.

[0032]

[0033] Table 1. Inhibition rates (%) of propanemidine and tetrafluoroether 10 μg / mL on mycelial growth of 9 pathogenic fungi.

[0034]

[0035] Table 1 shows that propanemid and tetraflufenicol exhibit good antibacterial activity against corn leaf blight, tomato gray mold, and rice blast fungus, with inhibition rates exceeding 95% at 10 μg / mL. Therefore, these three pathogens were selected for secondary screening.

[0036] Table 2. Virulence determination of propanemidin and tetraflurane against three pathogens.

[0037]

[0038] Table 2 shows that propanemid and tetraflufenicol have good antibacterial activity against corn leaf blight, tomato gray mold, and rice blast fungus. Tetraflufenicol is more toxic to the three pathogens than propanemid, and its EC50 content is higher. 50 The values ​​were all less than 1 μg / mL, indicating that propanemid had an EC50 value against the above three pathogens. 50 The values ​​were all less than 1.5 μg / mL.

[0039] Example 2: Synergistic effect of propanemidine and tetrafluoroetherazole

[0040] Using the mycelial growth rate method, fresh mycelial discs (Ф5mm) were taken from the edge of *Cephalotaxus fortunei* colonies cultured on PDAs for 6 days and inoculated onto PDA plates containing a series of concentrations of tetraflufenicol or propanemid, as well as on PDA plates containing a series of mixtures of tetraflufenicol and propanemid in different proportions. After 6 days of culture at 25℃, the colony diameter was measured, with each treatment repeated three times. The inhibition percentage of each agent was calculated by comparing it with a control without any agents. The median effective inhibitory concentration of each agent on the mycelial growth of the target fungus was calculated using probability value analysis. The synergistic coefficient of the mixed agents was calculated according to the following formula: a synergistic coefficient greater than 1.5 indicates a synergistic effect, between 0.5 and 1.5 indicates an additive effect, and less than 0.5 indicates an antagonistic effect (a and b are the proportions of propanemid and tetraflufenicol in the mixture, EC...). 50 (A) and EC 50 (B) is the effective intermediate concentration of propanemidine and tetrafluoroetherazole, EC 50 (Exp) is the concentration at which the theoretical inhibition occurs, EC 50 (Obs is the actual measured concentration).

[0041]

[0042] Table 3. Virulence of different ratios of propanemid and tetraflufenicol against maize leaf spot pathogen.

[0043]

[0044] Table 3 shows the effects of different ratios of propanemid and tetrafluoromethane on the EC50 of maize large spot mycelium. 50The synergistic effect values ​​are not the same, ranging from 0.5578 to 2.1530. When the ratio is 1:10 to 10:1, the synergistic effect value is greater than 0.5, indicating that there is an additive effect under the above ratios. In particular, there is a synergistic effect at 1:2, with a synergistic effect value of 2.1530. This indicates that propanemid and tetrafluoroethylene ether have a significant synergistic effect in controlling corn leaf blight under this ratio.

[0045] Example 3: Production of suspension A composed of 10% propanemidine and 20% tetrafluoroetherazole

[0046] Accurately weigh 111 kg of 90% propanemidine technical grade, then weigh 210 kg of 95% tetrafluoroetherazole technical grade, 90 kg of emulsifier calcium dodecylbenzenesulfonate, 40 kg of wetting and dispersing agent long-chain fatty alcohol polyoxyethylene ether, 20 kg of thickener polyvinyl alcohol, 20 kg of defoamer silicone, 10 kg of antifreeze propylene glycol, and 5 kg of preservative sodium benzoate into a mixing tank. Stir the mixture thoroughly in the mixing tank, then add water to bring the total to 1000 kg while stirring.

[0047] The sampled product was tested and found to contain 10% propanemid and 20% tetrafluoroether, resulting in a final product of 1 ton with a total effective component content of 30%.

[0048] Example 4: Production of water-dispersible granules B of a 1:2 composition of propanemidine and tetrafluoroetherazole

[0049] This embodiment provides a formulation for a 1:2 water-dispersible granule of propanemidine and tetrafluoroetherazole. The prepared water-dispersible granule of the compound drug is composed of the following raw materials: 222 kg of 90% propanemidine technical grade, 420 kg of 95% tetrafluoroetherazole technical grade, 100 kg of magnesium aluminum silicate dispersant, 50 kg of wetting agent (spreading powder), 50 kg of disintegrant (dry starch), 8 kg of carboxymethyl cellulose sodium binder, 50 kg of ascorbic acid stabilizer, and 100 kg of kaolin filler.

[0050] Propaneamidine technical, tetrafluoroetherazole technical, wetting agent, dispersant, disintegrant, stabilizer, and filler are mixed evenly and then pulverized by an air jet mill to produce an ultrafine wettable powder. A certain amount of water is then added, and the mixture is granulated by an extrusion granulator, dried by air jet drying, and sieved to obtain water-dispersible granules.

[0051] Example 5: The efficacy of a compound agent of propanemidin and tetrafluoroethylene ether azole against maize leaf spot disease.

[0052] Corn was sown at the Caoxinzhuang Experimental Station of Northwest A&F University on June 15, 2023. The first pesticide application was on July 22, and the second application was on August 1, for a total of two applications, with a water consumption of 750 L / hm². 2No pesticides for controlling other pests and diseases were used during the experiment. The experiment included eight treatments: a suspension of 10% propanediazole and 20% tetraflufenicol; water-dispersible granules of a 1:2 mixture of propanediazole and tetraflufenicol; a single application of 10% propanediazole suspension; a single application of 12.5% ​​tetraflufenicol emulsion; a control of 45% mancozeb aqueous solution; and a blank control of spraying an equal volume of water. Each concentration treatment was divided into three plots, each 33 m². 2 The experiment was conducted using a randomized block design. Results were collected according to GB / T 17980.107-2004, "Field Efficacy Test Guidelines for Pesticides (II) Part 107: Control of Maize Leaf Spot by Fungicides," and were assessed on August 16th, 15 days after the second application. The grading standards for maize leaf spot are as follows:

[0053] Grade 0: No lesions;

[0054] Grade 1: The area of ​​lesions accounts for less than 5% of the total leaf area of ​​the plant;

[0055] Grade 3: The lesion area accounts for 6% to 10% of the total leaf area;

[0056] Grade 5: The lesion area accounts for 11% to 25% of the total leaf area;

[0057] Grade 7: The lesion area accounts for 26% to 50% of the total leaf area;

[0058] Level 9: The lesion area accounts for more than 51% of the total leaf area of ​​the plant.

[0059] The method for calculating drug efficacy is as follows:

[0060] Disease index = [Σ(number of diseased leaves at each level × relative level value) / (total number of leaves surveyed × 9)] × 100;

[0061] Prevention and control effect (%) = [(disease index of blank control area - disease index of treatment area) / disease index of blank control area] × 100;

[0062] Table 4. Control efficacy of propanemidine and tetrafluoroethylene ether azole compound against maize leaf spot.

[0063]

[0064] Table 4 shows that the field trial results indicate that the combined use of propanemid and tetraflufenicol significantly enhances the control of maize leaf spot. The combined suspension concentrate A and the combined water-dispersible granules B, at 300 μg / mL, showed comparable control efficacy against maize leaf spot, both exceeding 90%, significantly better than the control efficacy of propanemid and tetraflufenicol alone at the same concentration, and significantly higher than the control efficacy of mancozeb.

[0065] Example 6: The efficacy of a compound agent of propanemidin and tetrafluoroethylene ether for the prevention and control of powdery mildew and gray mold in strawberries.

[0066] The experiment was conducted in a strawberry greenhouse. Seven days after application, the disease incidence rate of young fruits was investigated. Each concentration treatment was set up in three replicates, and 50 young fruits were randomly investigated in each replicate, for a total of 150 young fruits. The disease incidence rate was calculated by dividing the number of diseased fruits by the total number of fruits examined and then multiplying by 100%. The control effect was obtained by subtracting the disease incidence rate of the treatment area from the disease incidence rate of the control area, dividing by the disease incidence rate of the control area, and then multiplying by 100%.

[0067] Table 5. Efficacy of propanemidine and tetrafluoroethylene ether azole compound against gray mold in strawberries.

[0068]

[0069]

[0070] Table 6. Efficacy of propanemidine and tetrafluoroethylene ether azole compound against strawberry powdery mildew.

[0071]

[0072] As shown in Tables 5 and 6 above, the combination of propanetamidine and tetraflufenicol exhibits good control efficacy against both gray mold and powdery mildew in strawberries, with control efficiencies exceeding 85%. The control efficacy of the suspension concentrate is slightly better than that of its water-dispersible granules. The control efficacy of the combination concentrate is higher than or comparable to that of the single-agent formulation, and higher than that of the control agent. At the same dosage, the amount of single-agent formulation can be reduced.

[0073] Example 7: Efficacy of propanemidin and tetrafluoroetherazole compound formulation against rice blast disease

[0074] A trial of a compound agent of propanetamidine and tetraflufenicol against rice blast was conducted in Nanzheng District, Hanzhong City, Shaanxi Province. The tested rice variety was Huazheyou 210. Disease incidence was assessed 40 days after application. The grading standards for rice blast are as follows:

[0075] Level 0: No disease

[0076] Level 1: Less than 5% loss per ear (individual branches affected);

[0077] Level 3: Each ear of grain loses approximately 6%-20% (about 1 / 3 of the branches and stalks are affected);

[0078] Grade 5: Approximately 21%-50% loss per ear (disease on the neck or main axis, resulting in half-empty grains);

[0079] Level 7: Approximately 51%-70% loss per ear (caused by disease at the neck of the ear, resulting in mostly empty grains);

[0080] Grade 9: Approximately 71%-100% loss per ear (caused by disease at the neck of the ear, resulting in white ears);

[0081] Table 7. Efficacy of propanemid and tetrafluoroetherazole compound formulation against rice blast.

[0082]

[0083] As shown in Table 7 above, the combination formulation of propanetamidine and tetraflufenicol has a good control effect on rice blast, with control efficacy exceeding 80%. The control effect of the suspension concentrate is slightly better than that of its water-dispersible granules. The control effect of the combination formulation is higher than or comparable to that of the single agent, and significantly higher than that of the control agent.

[0084] In summary, propanetamidine and tetrafluoroethylene ether azole exhibit good control effects against maize leaf spot, powdery mildew, gray mold, and rice blast, and can be used as new alternative agents for the control of these diseases. Although the present invention has been described in detail above with general descriptions and specific embodiments, any modifications or improvements made without departing from the spirit of the invention are within the scope of protection claimed by the present invention.

Claims

1. A composition of a complex of a propane amidine and tetrafluthrin, characterized in that, The mass ratio of the propanediamine and tetrafluorothiopheneazole is (1-4):(8-1).

2. The complex composition of propane amidine and tetrafluthrin according to claim 1, characterized in that, The mass ratio of the propanediamine and tetrafluorothiopheneazole is 1:

2.

3. The use of the propanediamine and tetrafluorothiopheneazole compound composition of any one of claims 1-2 for preparing a compound bactericide; The compound bactericide is used for preventing and treating corn large spot.

4. Use according to claim 3, characterized in that, The dosage form of the compound bactericide includes a suspension or a water dispersible granule. In the compound bactericide, the propanediamine is 1-30% and the tetrafluorothiopheneazole is 1-40% by mass percentage.

5. A complex bactericide, characterized in that, The dosage form of the compound bactericide is a suspension. The suspension is composed of the following components by mass percentage: The propanediamine is 1-20%, the tetrafluorothiopheneazole is 1-40%, the emulsifier is 1-10%, the wet dispersant is 1-5%, the thickening agent is 1-5%, the defoaming agent is 0.15-4%, the antifreezing agent is 1-5%, the preservative is 1-5%, and water is added to 100%. The mass ratio of the propanediamine and tetrafluorothiopheneazole is (1-4):(8-1).

6. The combined bactericide of claim 5, characterized in that, The emulsifier is an anionic emulsifier or a nonionic emulsifier. The wet dispersant is at least one of an alkyl phenol resin polyvinyl ether, an alkyl benzene sulfonate, a long-chain fatty alcohol polyoxyethylene ether, an alkyl phenol polyoxyethylene ether, and a fatty alcohol sulfate. The thickening agent is polyvinyl alcohol, xanthan gum, sodium alginate, or hydroxypropyl methyl cellulose. The defoaming agent is an alkyne diol wetting defoaming agent or a silicone defoaming agent. The antifreezing agent is at least one of ethylene glycol, propylene glycol, glycerol, and polyethylene glycol. The preservative is sodium benzoate.

7. A combination bactericide, characterized in that, The dosage form of the compound bactericide is a water dispersible granule, and the components and weight percentage of the water dispersible granule are as follows: The propanediamine is 20-40%, the tetrafluorothiopheneazole is 20-40%, the wetting agent is 1-10%, the dispersant is 1-10%, the disintegrant is 1-5%, the binder is 0.5-5%, the stabilizer is 1-5%, and the filler is 1-10%, and the total amount is 100%. The mass ratio of the propanediamine and tetrafluorothiopheneazole is (1-4):(8-1).

8. The combined bactericide of claim 7, characterized in that, The wetting agent is pull-apart powder, the dispersant is magnesium aluminum silicate, the disintegrant is starch, the binder is sodium carboxymethyl cellulose, the stabilizer is ascorbic acid, and the filler is kaolin.

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