Application of tetrathiafulvalene as bactericide in bacterial diseases and bactericide

Abstract

The invention discloses application of tetrathiafulvalene as a bactericide in bacterial diseases and the bactericide, and relates to the technical field of food industry and agriculture. The invention relates to application of tetrathiafulvalene as a bactericide in bacterial diseases and the bactericide. The bacterial diseases comprise diseases caused by plant pathogenic bacteria and / or food-borne pathogenic bacteria. The invention aims to solve the problem of disease control in food industry and agriculture, and provides new application of tetrathiafulvalene in bacterial diseases. The invention provides application of tetrathiafulvalene in preventing and treating agricultural bacterial diseases caused by rice bacterial blight pathogenic bacteria, citrus ulcer pathogenic bacteria and pseudomonas solanacearum pathogenic bacteria and food pollution caused by escherichia coli, bacillus cereus, listeria monocytogenes, salmonella enteritidis and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of food industry and agricultural technology, and particularly relates to application of tetrathiafulvalene as a fungicide in bacterial diseases and the fungicide. BACKGROUND

[0002] Plant pathogens have a wide and profound impact on agriculture, affecting crop growth, yield and quality, economic costs, and other aspects. Pathogens can cause various diseases, leading to a significant reduction in crop yield. For example, in the cultivation of food crops, vegetables, fruits, and other crops, the yield of fruits, seeds, and other crops will be reduced due to pathogen invasion. However, with global warming and the frequent occurrence of extreme weather events, which provide favorable conditions for the reproduction and spread of pathogens, the frequency and severity of plant diseases continue to rise, threatening global food security. In addition, high temperature and humidity accelerate the spoilage of food.

[0003] Diseases not only lead to reduced crop yields, but also affect the quality of agricultural products, reducing their market value and causing significant economic losses to farmers and agricultural enterprises. In addition, the spread of diseases and food spoilage can also disrupt the balance of ecosystems, further exacerbating food security and food safety issues.

[0004] Currently, chemical pesticides and chemical preservatives are still the main means of preventing plant diseases and preserving food, but their overuse has led to environmental pollution, increased pathogen resistance, and potential food safety hazards, severely restricting the sustainable development of agriculture and the food industry. Exploring new environmentally friendly inhibitors is expected to accelerate the development of new pesticides.

[0005] The molecular architecture of tetrathiafulvalene is composed of two fulvalene units connected by sulfur atoms, forming a highly symmetrical planar conjugated system. Tetrathiafulvalene (TTF) is an organic sulfur compound formed by replacing the 2,2'-position of fulvalene with a sulfur atom, with a chemical formula of (H2C2S2C)2. It was first synthesized by Wudl in 1970, and its chloride salt was found to have high conductivity in 1972. The following year, its TCNQ salt was prepared, and it was found that the conductivity of the salt suddenly increased below room temperature. Although tetrathiafulvalene appears to be a 14π planar system, it lacks cyclic conjugation and therefore is not aromatic. It can be oxidized to a radical cation and a dication, both of which are thermodynamically stable and aromatic species. The oxidation reaction is stepwise and reversible. Tetrathiafulvalene is a strong π-electron donor, and salts formed with acceptors such as TCNQ are typical representatives of molecular conductors. These salts have high anisotropic conductivity, but their application areas are limited and have not been fully developed.

[0006] Therefore, developing natural and harmless alternatives to disease control and food preservation, and reducing reliance on chemical agents, has become a key path to achieving green transformation in agriculture and ensuring food safety. By combining technological innovation with ecological agriculture, we can expect to promote high-quality development of agriculture and the food industry while protecting the ecological environment, making a greater contribution to global food security, food safety, and ecological security. Summary of the Invention

[0007] To address the above shortcomings, the purpose of this invention is to solve the problem of disease control in the food industry and agriculture, and to provide a new application of tetrathionuron in bacterial diseases. This invention provides the application of tetrathionuron in controlling agricultural (plant) bacterial diseases caused by *Xanthomonas oryzae* PXO99A (rice bacterial blight pathogen), *Xanthomonas axonopodis* jx-6 (citrus canker pathogen), and *Pseudomonas solanacearum* Smith BNCC335855 (bacterial wilt pathogen), as well as food contamination caused by *Escherichia coli* O157:H7 ATCC 35150, *Bacillus cereus* BNCC 103930, *Listeria monocytogenes* ATCC 19115, and *Salmonella enteritidis* ATCC 14028. The specific technical solution is as follows: The application of tetrathionyl fulvaline as a fungicide in bacterial diseases, including diseases caused by plant pathogenic bacteria and / or foodborne pathogenic bacteria.

[0008] Preferred uses of tetrathionol for the prevention and treatment of plant diseases and for food preservation.

[0009] Preferably, the plant pathogenic bacteria is one or more of rice bacterial blight, citrus canker, and bacterial wilt pseudomonocyte disease.

[0010] Preferably, the foodborne pathogenic bacteria are one or more of Escherichia coli, Bacillus cereus, Listeria monocytogenes, and Salmonella enteritidis.

[0011] Preferably, the structure of the tetrathiofulvalene is as follows: .

[0012] Preferably, a bactericide containing the above-described tetrathionolene is provided, wherein the tetrathionolene is an active ingredient in the bactericide and its weight percentage in the bactericide is 1-99%.

[0013] Preferably, the bactericide is formulated as one of the following: soluble concentrate, water-dispersible granules, wettable powder, suspension concentrate, dispersible oil suspension, emulsifiable concentrate, dry suspension, and water emulsion.

[0014] Preferably, the bactericide further comprises an adjuvant and a carrier.

[0015] Preferably, the additive is selected from one or more of the following: alkylphenol formaldehyde resin polyoxyethylene ether, calcium dodecylbenzene sulfonate, sodium salt of phenol sulfonic acid condensate, polyether sulfates, separating powder, carboxymethyl cellulose, alkenyl sulfonate, lignin sulfonate, polyethylene glycol oleate, alkylphenol ether phosphate, ethylene glycol, xanthan gum, sodium benzoate, organosilicon, oleic acid polyether, alkylnaphthalene sulfonate, silica, polycarboxylate, sulfate polyether multi-component complex, sodium dodecylbenzene sulfonate, fatty alcohol polyoxyethylene ether phosphate, and urea.

[0016] Preferably, the carrier is one or more of the following: aromatic solvent oil S-200#, cyclohexanone, kaolin, water, methyl oleate, or xylene.

[0017] Preferably, the fungicide has a MIC value of 6.25 μg / mL against rice bacterial blight pathogen.

[0018] Preferably, the MIC value of the bactericide against Escherichia coli, Bacillus cereus, Listeria monocytogenes, and Salmonella enteritidis is 3.12 μg / mL.

[0019] Compared with the prior art, the beneficial effects of the present invention are: 1. The present invention discovers that tetrathiofulvalene compounds have antibacterial activity against bacterial diseases, particularly those caused by plant pathogens and / or foodborne pathogens. Specifically, they exhibit good antibacterial activity against three plant pathogens: rice bacterial blight, citrus canker, and bacterial wilt pseudomonas. For rice bacterial blight, the MIC value is 6.25 μg / mL, and the inhibition rate reaches over 80% at a concentration of 3.12 μg / mL. Furthermore, tetrathiofulvalene compounds also show excellent antibacterial activity against foodborne pathogens, with MIC values ​​reaching 3.12 μg / mL against *Escherichia coli*, *Listeria monocytogenes*, and *Salmonella enteritidis*. 2. The tetrathiofulvalene compound of the present invention has a simple structure, low toxicity, and low residue, which meets the needs of green and environmentally friendly agriculture and has broad application prospects. Detailed Implementation

[0020] The specific embodiments of the present invention are described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments. Unless otherwise defined, all technical terms used below have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing specific embodiments only and are not intended to limit the scope of protection of the present invention. Unless otherwise specifically stated, all raw materials, reagents, instruments, and equipment used in the present invention are commercially available or can be prepared by existing methods.

[0021] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0022] Frequent occurrences of agricultural pests and diseases not only severely affect crop yield and quality, but the spread of diseases and food spoilage can also seriously disrupt the balance of the ecosystem and further exacerbate food safety issues. In order to prevent agricultural pests and diseases, the inventor has been committed to the research of fungicides.

[0023] This invention tested the antibacterial effects of tetrathiofulvalene compounds against plant pathogenic bacteria and / or foodborne pathogenic bacteria. The results showed that they have broad-spectrum and excellent antibacterial activity, providing new ideas for the development of plant antibacterial agents and food antifungal and preservative agents.

[0024] Specifically, the present invention provides the application of tetrathione-fulvalene as a fungicide in bacterial diseases, including diseases caused by plant pathogenic bacteria and / or foodborne pathogenic bacteria.

[0025] Specifically, the present invention provides the use of tetrathiofulvalene in the prevention and control of plant diseases and food preservation.

[0026] Specifically, the plant pathogenic bacteria mentioned in this invention are one or more of rice bacterial blight, citrus canker, and bacterial wilt pseudomonocyte disease.

[0027] Specifically, the foodborne pathogens mentioned in this invention are one or more of Escherichia coli, Bacillus cereus, Listeria monocytogenes, and Salmonella enteritidis.

[0028] The structure of tetrathiofulvalene mentioned in the embodiments of this invention is as follows: .

[0029] Specifically, the present invention provides a bactericide containing the above-mentioned tetrathionolene, wherein the tetrathionolene is an active ingredient in the bactericide and its weight percentage in the bactericide is 1 to 99%.

[0030] Specifically, the bactericide of the present invention is formulated as one of the following: soluble concentrate, water-dispersible granules, wettable powder, suspension concentrate, dispersible oil suspension, emulsifiable concentrate, dry suspension, and water emulsion.

[0031] Specifically, the bactericide of the present invention also includes adjuvants and a carrier.

[0032] More specifically, the additives of the present invention are selected from one or more of the following: alkylphenol formaldehyde resin polyoxyethylene ether, calcium dodecylbenzene sulfonate, sodium salt of phenol sulfonic acid condensate, polyether sulfates, separating powder, carboxymethyl cellulose, alkenyl sulfonate, lignin sulfonate, polyethylene glycol oleate, alkylphenol ether phosphate, ethylene glycol, xanthan gum, sodium benzoate, organosilicon, oleic acid polyether, alkyl naphthalene sulfonate, silica, polycarboxylate, sulfate polyether multi-component complex, sodium dodecylbenzene sulfonate, fatty alcohol polyoxyethylene ether phosphate, and urea.

[0033] More specifically, the carrier of the present invention is one or more of the following: aromatic solvent oil S-200#, cyclohexanone, kaolin, water, methyl oleate, or xylene.

[0034] Specifically, the MIC value of the fungicide of the present invention against rice bacterial blight pathogen is 6.25 μg / mL.

[0035] Specifically, the MIC value of the bactericide of the present invention against Escherichia coli, Bacillus cereus, Listeria monocytogenes, and Salmonella enteritidis is 3.12 μg / mL.

[0036] Example 1: Preparation of 15% tetrathione fulvalene soluble concentrate A bactericide containing the above-mentioned tetrathiofulvalene is made from the following raw materials in weight percentage: 15% tetrathiofulvalene, 7% alkylphenol formaldehyde resin polyoxyethylene ether, 2% calcium dodecylbenzenesulfonate, and the balance being aromatic solvent oil S-200#; the preparation method is as follows: the above raw materials are mixed and stirred in proportion, and after complete dissolution, a soluble bactericide is obtained.

[0037] Example 2: Preparation of 50% tetrathione-fulvalene water-dispersible granules A bactericide containing the above-mentioned tetrathionolene is made from the following raw materials in weight percentage: 50% tetrathionolene, 7% sodium phenolsulfonic acid condensate (dispersant), 2% polyether sulfate (dispersant), 3% stretching powder (wetting agent), 2% carboxymethyl cellulose (binder), 2% urea (disintegrant), and the balance being kaolin (filler); the preparation method is as follows: the above raw materials are mixed evenly in proportion, then added to an air jet mill for pulverization, then granulated and sieved to obtain a water-dispersible granule bactericide.

[0038] Example 3: Preparation of 70% Tetrathione-Fuvalene Wettable Powder A fungicide containing the above-mentioned tetrathionolene is made from the following raw materials in weight percentage: 70% tetrathionolene, 8.4% alkenyl sulfonate (wetting and dispersing agent), 4% lignin sulfonate (dispersing agent), and the balance being kaolin (filler); the preparation method is as follows: the above raw materials are mixed evenly in proportion, and then added to an air jet mill for pulverization to obtain a wettable powder fungicide.

[0039] Example 4: Preparation of 30% tetrathione fulvalene suspension A bactericide containing the above-mentioned tetrathionol fulvaline is made from the following raw materials in weight percentages: 30% tetrathionol fulvaline, 6.2% polyethylene glycol oleate (wetting and dispersing agent), 2.3% alkylphenol ether phosphate (wetting agent), 3% sodium dodecylbenzenesulfonate, 2% ethylene glycol, 0.3% xanthan gum (thickening agent), 0.1% sodium benzoate (preservative), 0.5% organosilicon (defoamer), and the balance being water; the preparation method is as follows: the above raw materials are mixed in proportion, then subjected to high-speed shearing, and then ground in a sand mill for 2-3 hours to obtain a suspension bactericide.

[0040] Example 5: Preparation of 20% tetrathione-fulvalene dispersible oil suspension A bactericide containing the above-mentioned tetrathionolene is made from the following raw materials in weight percentages: 20% tetrathionolene, 5.3% oleic acid polyether (emulsifier), 4.8% alkyl naphthalene sulfonate (emulsifier), 1% calcium dodecylbenzenesulfonate (emulsifier), 0.5% silica (thickener), and the balance being methyl oleate (filler); the preparation method is as follows: tetrathionolene and other components are added together to a sand mill and ground to obtain a bactericide that can dispersible oil suspension.

[0041] Example 6: Preparation of 40% tetrathione-fulvalene dry suspension A bactericide containing the above-mentioned tetrathionolene is made from the following raw materials by weight percentage: 40% tetrathionolene, 6.3% polycarboxylate (SP-27001) (dispersant), 2.7% sulfate polyether multi-component compound (dispersant), 3% sodium dodecylbenzenesulfonate (wetting agent), and the balance being water (filler). The preparation method is as follows: the tetrathionolene technical material, wetting agent, dispersant and filler are mixed evenly in proportion, and then pre-dispersed in a shear mill at 8000 r / min for 5 min; then pumped into a sand mill and sand-milled at 1800 r / min for 5-15 min; finally, spray-drying is carried out in a high-temperature spray tower to obtain a dry suspension bactericide.

[0042] Example 7: Preparation of 25% tetrathiofulvalene emulsifiable concentrate A bactericide containing the above-mentioned tetrathionol fulvalene is made from the following raw materials in weight percentage: 25% tetrathionol fulvalene, 5.6% fatty alcohol polyoxyethylene ether phosphate (emulsifier), 3.4% calcium dodecylbenzenesulfonate (emulsifier), and the balance being xylene (filler); the preparation method is as follows: the above raw materials are mixed evenly in proportion and stirred for 30 minutes. After the tetrathionol fulvalene is completely dissolved, a transparent homogeneous liquid emulsion bactericide is obtained.

[0043] Example 8: Preparation of a 10% tetrathiofulvalene aqueous emulsion A bactericide containing the above-mentioned tetrathionol is made from the following raw materials in weight percentages: 10% tetrathionol, 15% cyclohexanone, 6% alkylphenol ether phosphate emulsifier, 4% calcium dodecylbenzenesulfonate, 3% polyether sulfate, 2% ethylene glycol antifreeze, and water to make up to 100%. The preparation method is as follows: Tetrathionol is first dissolved in a mixture of cyclohexanone, alkylphenol ether phosphate emulsifier, 4% calcium dodecylbenzenesulfonate, and polyether sulfate, and stirred to form a homogeneous oil phase; a portion of water and ethylene glycol antifreeze are mixed together to form a homogeneous aqueous phase; in a reaction vessel, while stirring at high speed, the oil phase is added to the aqueous phase, and a shearing machine is turned on for high-speed shearing, with the remaining water added to make up the volume. Shearing is performed for about half an hour to form a homogeneous liquid, thus obtaining the tetrathionol water-emulsion bactericide.

[0044] Example 9: Indoor antibacterial activity determination of tetrathionuron against plant pathogenic bacteria The strains used in this embodiment (such as rice bacterial blight pathogen, citrus canker pathogen, and Ralstonia solanacearum pathogen) were provided by Lanzhou University. The strains were frozen in the laboratory at -80℃ with 30% glycerol.

[0045] The frozen bacterial strains were retrieved and streaked onto NA solid medium (beef extract: 3g, peptone: 5g, yeast extract: 1g, sucrose: 10g, agar: 15g, distilled water: 1L, pH 7.0; sterilized at 121℃ for 20min) and incubated at 28℃ until single colonies appeared. Single colonies from the solid medium were transferred to NB liquid medium (beef extract: 3g, peptone: 5g, yeast extract: 1g, sucrose: 10g, distilled water: 1L; sterilized at 121℃ for 20min) and cultured on a shaker at 28℃ and 180rpm until the logarithmic growth phase (OD value between 0.3 and 0.6). The strains in the logarithmic growth phase were diluted with NB liquid medium to approximately 10... 6 CFU / mL available for use.

[0046] The tetrathiofulvalene compounds were dissolved separately in DMSO and added to NB liquid medium. The mixtures were thoroughly mixed to prepare a drug-containing liquid medium with a concentration of 200 μg / mL. 50 μL of the drug-containing medium and the same volume of approximately 10...6 CFU / mL cultures of plant pathogenic bacteria (specifically, *Rhizoctonia solani*, *Citrus canker*, and *Rhizoctonia solani*) were added to the wells of a 96-well plate, with a final drug concentration of 100 μg / mL. A control experiment was conducted using 100 μL of bacterial suspension containing an equal amount of DMSO.

[0047] The 96-well plates were incubated at 28°C for 24-48 hours until bacterial growth was observed in the control group (OD value between 0.25-0.35). The OD value of the bacterial culture in each well was then measured using a microplate reader. 600 In addition, the OD values ​​of 100 μL of liquid culture medium and a 100 μg / mL drug concentration were measured to correct for the OD values ​​caused by the culture medium and the drug itself. The formulas for calculating the corrected OD value and inhibition rate are as follows: Correcting OD 600 =O2 in bacterial culture medium 600 - OD of sterile cultures 600 ; All experiments were conducted in triplicate, and the average value was taken as the result. The inhibitory effect of tetrathionol on three plant pathogenic bacteria, namely *Rhizopus oryzae*, *Rhizopus canker*, and *Rhizopus bacillus*, was determined. The results are shown in Table 1.

[0048] Table 1. Antibacterial effect of tetrathionuron at different concentrations against plant pathogenic bacteria. Note: "-" indicates that the inhibition rate of this compound was not tested.

[0049] The drug-containing liquid culture medium of the active compound was diluted in 96-well plates using a two-fold dilution method to obtain a series of 50 μL drug-containing culture media of various concentrations. Then, the inhibition rate corresponding to the series of concentrations was determined according to the same experimental method as in Example 2. The lowest concentration with an inhibition rate greater than 90% was defined as the MIC. All experiments were performed in triplicate, and the average value was taken as the result. The measured activity data are shown in Table 2.

[0050] Table 2. MIC values ​​(μg / mL) of tetrathionuron against plant pathogenic bacteria. As shown in Tables 1 and 2, the tetrathiofulvalene compound involved in this invention has good antibacterial activity against three plant bacteria in the laboratory. It can achieve an inhibition rate of more than 90% against rice bacterial blight, citrus canker, and Ralstonia solanacearum at 50 ppm. In particular, the MIC value against rice bacterial blight can reach 6.25 μg / mL. Its inhibitory activity is significantly better than that of the commercial agent quinolinone (MIC≥12.5 μg / mL).

[0051] Example 10: Indoor antibacterial activity assay of tetrathionuron against foodborne pathogenic bacteria The micro-broth dilution method was used: *Escherichia coli*, *Bacillus cereus*, *Listeria monocytogenes*, and *Salmonella enteritidis* were inoculated into 20 mL of MH medium, and then incubated at 37°C for 18-24 h in a shaker at 150 rpm. An appropriate amount of bacterial culture was taken and the absorbance at 600 nm was measured using a microplate reader. A culture medium without bacteria was used as a blank control. Based on OD6000.1, the equivalent concentration was 1 × 10⁻⁶. 8 CFU / mL, the bacterial suspension was diluted to a concentration of 1×10⁻⁶ using MH medium. 6 After preparing the bacterial culture at CFU / mL, it is ready for use.

[0052] Dissolve the compounds separately in DMSO, add them to liquid culture medium, mix thoroughly, and prepare a drug-containing liquid culture medium with a concentration of 800 μg / mL. Take 50 μL of the drug-containing liquid culture medium and the same volume containing approximately 1×10⁻⁶... 6 CFU / mL bacterial culture was added to the wells of a 96-well plate, with a final drug concentration of 400 μg / mL. A control group of 100 μL bacterial culture containing an equal amount of DMSO was used. The 96-well plates were incubated at 37℃ for 18–24 h until bacterial growth was observed in the control group. The OD600 of the bacterial culture in each well was measured using a microplate reader. The OD600 of 100 μL of liquid culture medium and the 400 μg / mL drug concentration were also measured separately to correct for OD600 caused by the culture medium and drug itself. The formulas for calculating the corrected OD value and inhibition rate are as follows: Correcting OD 600 =O2 in bacterial culture medium 600 - OD of sterile cultures 600 ; All experiments were conducted in triplicate, and the average value was taken as the result. The inhibitory activity of tetrathionuron against four foodborne pathogenic bacteria (Escherichia coli, Bacillus cereus, Listeria monocytogenes, and Salmonella enteritidis) was measured. The experimental results are shown in Table 3 below.

[0053] Table 3. Antibacterial effect of tetrathionuron against foodborne pathogens Note: "-" indicates that the inhibition rate of this compound was not tested.

[0054] The drug-containing liquid culture medium of the active compound was diluted in 96-well plates using a two-fold dilution method to obtain a series of 50 μL drug-containing media of various concentrations. Then, the inhibition rate corresponding to the series of concentrations was determined according to the above experimental method. The lowest concentration with an inhibition rate greater than 90% was defined as the MIC. All experiments were performed in triplicate, and the measured activity data are shown in Table 4.

[0055] Table 4. MIC values ​​(μg / mL) of tetrathionuron against foodborne pathogens. As shown in Tables 3 and 4, tetrathione exhibits excellent antibacterial activity against four foodborne pathogenic bacteria tested: Escherichia coli, Bacillus cereus, Listeria monocytogenes, and Salmonella enteritidis. When the compound concentration is 6.25 μg / mL, its inhibition rate reaches over 90%, and its inhibitory activity is superior to that of the positive control drug ∑-polylysine.

[0056] This demonstrates that tetrathione fulvalene possesses excellent antibacterial activity and has potential for further development into a novel bactericide and a preventative agent for food mold and spoilage.

[0057] Example 11: Field trial of tetrathionuron for the control of bacterial leaf blight in rice Test reagents: 20% 4-fluoro-3,6-dichloropyridazine dry suspension prepared in Example 4; 40% 3,6-dichloropyridazine-4-formonitrile water-dispersible granules prepared in Example 7; Control agent 1: 6% kasugamycin soluble solution, registration certificate number PD20211959, Fujian Kaili Biological Products Co., Ltd.

[0058] Control agent 2: 40% quinoline copper suspension, registration certificate number PD20200363, Liuzhou Huinong Chemical Co., Ltd.

[0059] The blank control was water.

[0060] Experimental Method: Potted leaf-cutting inoculation method. Preparation of the bacterial solution: Dissolve the bacterial suspension of *Bacillus cereus* to a suitable concentration using sterile water. Using sterile scissors, dip the scissors into the bacterial solution and cut the leaf about 2 cm from the tip, allowing the bacterial solution to seep in naturally through the wound. Cut 30 leaves from each rice pot. After inoculation, cover with plastic to maintain moisture. One day after inoculation, according to the dosage in Table 5, dilute with 60 L of water and spray onto the rice leaves, spraying both sides of the leaves until dripping water. Each treatment had 5 rice pots, with 4 replicates. Rice treated with an equal amount of sterile water served as a blank control. All pots were incubated for 14 days in a greenhouse at 40℃, partial light, and relative humidity above 80%. Disease index was investigated, and relative control efficacy was calculated.

[0061] Grading standards for bacterial blight of rice: Level 0: No disease; Level 1: Lesions less than 0.5cm; Level 3: Lesions between 0.5 and 3cm; Level 5: Lesions between 3 and 6cm; Level 7: Lesions between 6 and 10cm; Level 9: Lesions more than 10cm.

[0062] Disease index (%) = [∑(number of diseased leaves at each level × representative value at each level) / (total number of leaves surveyed × highest representative value)] × 100.

[0063] Relative efficacy (%) = (Control disease index - Treatment disease index) / Control disease index × 100.

[0064] Table 5. Results of field trials for the control of rice bacterial leaf blight As shown in Table 5 above, the control efficacy of tetrathionuron-methyl for rice bacterial blight is higher than that of 40% quinoline copper suspension and 6% kasugamycin soluble concentrate. It has the value for further research and is expected to be developed into a new type of agricultural antibacterial agent to replace the drug agents that have produced resistance on the market.

[0065] Therefore, the tetrathiofulvalene described in this invention exhibits good control efficacy against plant pathogenic bacteria or foodborne pathogenic bacteria, and shows promising research prospects in the control of agricultural pathogens, making it worthy of further research and development.

[0066] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. The application of tetrathionyl fulvalene as a fungicide in bacterial diseases, characterized by: The bacterial diseases mentioned include those caused by plant pathogenic bacteria and / or foodborne pathogenic bacteria.

2. The application according to claim 1, characterized in that, The plant pathogenic bacteria are one or more of rice bacterial blight, citrus canker, and bacterial wilt pseudomonocyte disease.

3. The application according to claim 1, characterized in that, The foodborne pathogens are one or more of Escherichia coli, Bacillus cereus, Listeria monocytogenes, and Salmonella enteritidis.

4. A bactericide comprising the tetrathiofulvalene of claim 1, characterized in that, The tetrathiofulvalene is used as an active ingredient in the bactericide, and its weight percentage in the bactericide is 1-99%.

5. The bactericide according to claim 4, characterized in that, The bactericide is formulated as one of the following: soluble concentrate, water-dispersible granules, wettable powder, suspension concentrate, dispersible oil suspension, emulsifiable concentrate, dry suspension, and water emulsion.

6. The bactericide according to claim 4, characterized in that, The bactericide also includes adjuvants and carriers.

7. The bactericide according to claim 6, characterized in that, The additives are selected from one or more of the following: alkylphenol formaldehyde resin polyoxyethylene ether, calcium dodecylbenzene sulfonate, sodium salt of phenol sulfonic acid condensate, polyether sulfates, separating powder, carboxymethyl cellulose, alkenyl sulfonate, lignin sulfonate, polyethylene glycol oleate, alkylphenol ether phosphate, ethylene glycol, xanthan gum, sodium benzoate, organosilicon, oleic acid polyether, alkylnaphthalene sulfonate, silica, polycarboxylate, sulfate polyether multi-component complex, sodium dodecylbenzene sulfonate, fatty alcohol polyoxyethylene ether phosphate, and urea.

8. The bactericide according to claim 6, characterized in that, The carrier is one or more of the following: aromatic solvent oil S-200#, cyclohexanone, kaolin, water, methyl oleate, or xylene.

9. The bactericide according to claim 4, characterized in that, The MIC value of the fungicide against rice bacterial blight pathogen is 6.25 μg / mL.

10. The bactericide according to claim 4, characterized in that, The MIC value of the bactericide against Escherichia coli, Bacillus cereus, Listeria monocytogenes, and Salmonella enteritidis is 3.12 μg / mL.

Images