Use of a fungicidal composition for controlling anthracnose of watermelon

Abstract

The present application provides a use of a fungicidal composition for preventing and treating watermelon anthracnose, and particularly relates to a fungicidal composition with effective active ingredients of trifloxystrobin and bromoxynil, characterized in that the weight ratio of trifloxystrobin to bromoxynil is 4:1-1:4, and the fungicidal composition is in the form of an aqueous emulsion. The composition of the present application is prepared by mixing trifloxystrobin and bromoxynil in a certain ratio to form an aqueous emulsion, which has a good effect on preventing and treating watermelon anthracnose, especially when used in the disease onset period, can effectively treat the disease, and has the advantages of high activity, good quick-acting property, long effective period and safety.

Description

Technical Field

[0001] This invention belongs to the field of pesticide technology, specifically relating to the use of a fungicide composition for the prevention and control of anthracnose in watermelon. The fungicide composition consists of oxadiazon, bromodiphenyl ether, synergist, and adjuvant. Background Technology

[0002] Azoxystrobin is a novel fluorinated fungicide successfully developed from the natural product strobilurins as a lead compound. It possesses characteristics such as high efficiency, broad spectrum, protective, curative, eradicative, penetrating, systemic activity, resistance to rain washout, and long-lasting effect. It is effective against strains resistant to 1,4-demethylase inhibitors, benzamides, dicarboxyamines, and benzimidazoles, and shows no cross-resistance with existing fungicides. It exhibits good activity against almost all fungal diseases (Ascomycetes, Basidiomycetes, Oomycetes, and Deuteromycetes), such as powdery mildew, rust, malaria blight, net blotch, downy mildew, and rice blast. In addition to its specific efficacy against powdery mildew and leaf spot, it also shows good activity against rust, downy mildew, damping-off, apple black spot, and rapeseed sclerotinia stem rot. It is safe for crops and environmentally friendly due to its rapid degradation in soil and water. Due to its broad-spectrum, penetrating, and rapid distribution properties, oxadiazon is quickly absorbed by crops. Furthermore, its upward systemic activity provides excellent resistance to rain washout and a long-lasting effect, thus it is considered a second-generation methoxyacrylate fungicide. Oxadiazon is primarily used for foliar application, exhibiting excellent protective activity and some curative activity, unaffected by environmental conditions. The optimal application period is during spore germination and the early stages of disease development, but it is active against black spot disease at all stages.

[0003] Bromhizobium is a new generation of highly efficient broad-spectrum fungicide with unique protective, systemic therapeutic, and eradicative functions. It is suitable for fungal and bacterial diseases of various fruit trees, vegetables, tobacco, medicinal herbs, and other crops. It has significant effects and a long-lasting effect. It can be rapidly absorbed by fungal cells and translocated within the cells, inhibiting the amino acid metabolism esterase system of pathogens and disrupting the protein biosynthesis of pathogens, thereby interfering with the normal development of fungal cells. This achieves antibacterial and bactericidal effects. It can also stimulate the activity of various enzymes in crops, increase photosynthesis, make leaves dark green, and make plants robust, thereby increasing crop yield.

[0004] Watermelon anthracnose can occur in most watermelon-producing areas worldwide, but it is most prevalent and severe in humid climates. Under suitable climatic conditions, the disease can occur from the seedling stage to the early, middle, and late stages of growth, with the most severe damage occurring in the middle and late stages. It causes fruit rot and stem and leaf death, making it a major cause of fruit rot during watermelon transportation and storage. The incidence rate of watermelon anthracnose is 10-20%, resulting in a yield loss of 10-15%. In severe cases, the incidence rate can reach 100%, with yield losses exceeding 40%.

[0005] Watermelon anthracnose is highly contagious and spreads rapidly. The pathogen overwinters in plant debris or soil. The following year, when temperature and humidity are suitable, the overwintering pathogen produces spores, which then begin to infect the plant. Conidia are primarily spread through water, wind, rain, and human activities. Currently, most treatments for watermelon anthracnose focus on prevention, i.e., applying pesticides before disease onset. Once anthracnose occurs, few products can quickly control the disease, especially when the disease is severe, leaving growers with almost no effective treatment options. Providing a product that effectively controls watermelon anthracnose, is environmentally friendly, safe, and has a long-lasting effect is a pressing issue for researchers in this field.

[0006] Through experiments, the inventors discovered that by combining azoxystrobin and bromodiphenyl ether in a certain proportion to form an emulsion composition, which have different mechanisms of action, the occurrence of anthracnose in watermelons can be effectively controlled, reducing pesticide usage, lowering farmers' control costs, and ensuring crop safety. Summary of the Invention

[0007] The purpose of this invention is to provide a fungicide composition for the prevention and control of anthracnose in watermelons. It can rapidly control the spread of anthracnose, especially after the onset of the disease, and also has a good control effect on resistant diseases.

[0008] The technical solution of this invention is:

[0009] The use of a fungicide composition for controlling anthracnose in watermelon, wherein the effective active ingredients of the fungicide composition are oxadiazon and bromodiflubenzuron, wherein the weight ratio of oxadiazon to bromodiflubenzuron is 4:1 to 1:4, and the preferred weight ratio is 1:4.

[0010] Furthermore, the bactericidal composition contains oxadiazon, bromodiphenyl ether, synergists, and adjuvants, and the composition is in the form of an emulsion.

[0011] Furthermore, the total weight of oxadiazon and bromodiphenyl ether in the bactericidal composition is 10% to 50%, preferably 25%.

[0012] Furthermore, the dosage of the active ingredient in the bactericidal composition is 225–300 g / ha.

[0013] Furthermore, the synergist is selected from one or more of styrene-acrylic emulsion, rosin diene, alkyl polyglycoside, fatty alcohol polyoxyethylene ether, polyether-modified heptamethyltrisiloxane, and rosin-based vegetable oil.

[0014] Furthermore, the additives are selected from one or more of solvents, emulsifiers, antifreeze agents, defoamers, pH adjusters, and water.

[0015] When the bactericidal composition is formulated into an emulsion, it contains the following components and contents: 2-40% oxadiazon, 2-40% bromodiphenyl ether, 3-10% synergist, 1-30% solvent, 1-20% emulsifier, 1-5% antifreeze, 0.1-1% defoamer, 0-1% pH adjuster, and water as the balance.

[0016] Compared with the prior art, the fungicidal composition of the present invention for the prevention and control of anthracnose in watermelon has the following beneficial effects: (1) Compared with single agents, the composition has a more significant synergistic effect on the prevention and control of anthracnose in watermelon; (2) The combination of two compounds with different mechanisms of action can effectively delay the development of drug resistance in the disease, especially when used in the early stage of disease, it can effectively control the spread of the disease and has good rapid effect; (3) It has a broad spectrum of prevention and control, and in addition to effectively preventing and controlling anthracnose, it also has a good effect on other fungal and bacterial diseases; (4) It can promote the synthesis of chlorophyll in watermelon leaves, enhance photosynthesis, and treat diseases and increase yield; (5) The product has low toxicity and is safe for melons; (6) Applying the medicine after the disease occurs reduces the amount of medicine used and lowers the cost of medicine. Detailed Implementation

[0017] The present invention will be further described below with reference to the embodiments. The percentages in the embodiments are all weight percentages, but the present invention is not limited thereto.

[0018] Application Example 1

[0019] Example 1: 25% azoxystrobin·bromodiphenyl ether emulsion

[0020] A 25% azoxystrobin·bromodiphenyl ether emulsion was prepared by comprising 5% azoxystrobin technical, 20% bromodiphenyl ether technical, 2% fatty alcohol polyoxyethylene ether, 10% phenyl methyl acetate, 15% No. 150 solvent oil, 3% castor oil polyoxyethylene ether, 1.5% polyoxyethylene-polyoxypropylene block copolymer, 5% urea, 0.1% silicone defoamer, 0.15% anhydrous citric acid, and water as the balance.

[0021] Example 2: 25% azoxystrobin·bromodiphenyl ether emulsion

[0022] A 25% azoxystrobin·bromodiphenyl ether emulsion was prepared by comprising 5% azoxystrobin technical, 20% bromodiphenyl ether technical, 5% alkyl polyglycoside, 6% cyclohexanone, 15% No. 200 solvent oil, 4% alkylphenol polyoxyethylene ether, 3% propylene glycol, 0.2% fatty alcohol, and water as the balance.

[0023] Example 3: 10% azoxystrobin·bromodiphenyl ether emulsion

[0024] A 10% azoxystrobin·bromodiphenyl ether emulsion was prepared by mixing 2% azoxystrobin technical, 8% bromodiphenyl ether technical, 8% styrene-acrylic emulsion, 12% methanol, 5% 200# solvent oil, 3% fatty alcohol polyoxyethylene ether, 3% urea, 0.1% organosilicone defoamer, 0.1% anhydrous citric acid, and water as the balance.

[0025] Example 4: 30% azoxystrobin·bromodiphenyl ether emulsion

[0026] A 30% azoxystrobin·bromodimethalin water emulsion was prepared by comprising 10% azoxystrobin technical, 20% bromodimethalin technical, 4% polyether-modified heptamethyltrisiloxane, 8% dimethyl sulfoxide, 10% N,N-dimethylacetamide, 5% 150# solvent oil, 2% nonylphenol polyoxyethylene ether, 2% polyoxyethylene polyoxypropylene block copolymer, 4% ethylene glycol, 0.15% fatty acid, and water as the balance.

[0027] Example 5: 40% azoxystrobin·bromodiphenyl ether emulsion

[0028] A 40% azoxystrobin·bromodiflubenzuron water emulsion was prepared by comprising 20% ​​azoxystrobin technical, 20% bromodiflubenzuron technical, 10% rosinyl vegetable oil, 15% ethyl acetate, 10% cyclohexanone, 3% polyol fatty acid esters and their ethylene oxide adducts, 3% alkyl glycosides, 3% glycerol, 0.1% fatty alcohol, and water as the balance.

[0029] Implementation Example 2:

[0030] Toxicity test of a mixture of oxadiazon and bromodiphenyl ether for watermelon anthracnose

[0031] According to the standards NY / T1156.2-2006 and NY / T1156.6-2006, the toxicity of azoxystrobin and bromuconazole in their respective ratios of 1:1, 1:2, 2:1, 1:4, and 4:1 against *Agrostis chinensis*, the causal agent of watermelon anthracnose, was determined using the plate method. The results showed that the mixtures of azoxystrobin and bromuconazole in the above five ratios exhibited a synergistic effect against *Agrostis chinensis*. The experimental procedure is as follows:

[0032] 1. Experimental Objective

[0033] The toxicity of azoxystrobin and bromodiflubenzuron, as well as their different ratios, against watermelon anthracnose fungus was determined in the laboratory, and their synergistic effect was evaluated. The compatibility between the two was clarified, providing a scientific basis for the research and development of azoxystrobin and bromodiflubenzuron mixtures.

[0034] 2. Test conditions

[0035] 2.1 Test Target

[0036] The anthracnose fungus (Colletotrichum lagenarium (Pass.) Ell. et Halst) was preserved and provided by Hunan Aimiao Testing Co., Ltd.

[0037] 2.2 Cultivation Conditions

[0038] The culture conditions for the test targets and the targets after the experiment were a temperature of 25±5℃ and a relative humidity of 65±5%.

[0039] 2.3 Instruments and Equipment

[0040] Beakers, pipettes, graduated cylinders, petri dishes, autoclaves, intelligent artificial climate incubators, etc.

[0041] 3 Experimental Design

[0042] 3.1 Test reagents

[0043] Azoxystrobin 96% technical grade; Bromhexanil 95% technical grade.

[0044] 3.2 Reagent Concentration Design and Solution Preparation

[0045] Bromhizobium solution: Weigh 0.0421g of 95% bromhizobium technical grade, dissolve it in 0.5mL of LDM, and bring the volume to 100mL with sterile water containing 0.1% Tween 80 emulsifier. Shake well to prepare a solution with a concentration of 400mg / L. Then dilute it with sterile water containing 0.1% Tween 80 emulsifier to concentrations of 200, 100, 50, 25, and 12.5mg / L for later use.

[0046] Azoxystrobin solution: Weigh 0.0417g of 96% azoxystrobin technical grade, dissolve in 0.5mL DMF, and bring the volume to 100mL with sterile water containing 0.1% Tween 80 emulsifier. Shake well to prepare a solution with a concentration of 400mg / L. Then dilute with sterile water containing 0.1% Tween 80 emulsifier to concentrations of 200, 100, 50, 25, and 12.5mg / L for later use.

[0047] Each mixed solution: Take 10, 10, 20, 5, and 20 mL of 400 mg / L bromodiflubenzuron solution and add them to 10, 20, 10, 20, and 5 mL of 400 mg / L azoxystrobin solution to prepare 400 mg / L bromodiflubenzuron·azoxystrobin 1:1, 1:2, 2:1, 1:4, and 4:1 solutions, respectively. Then dilute with sterile water containing 0.1% Tween 80 emulsifier to concentrations of 200, 100, 50, 25, and 12.5 mg / L for later use.

[0048] Control solution: 0.5 mL DMF plus 99.5 mL sterile water containing 0.1% Tween 80 emulsifier.

[0049] 4 Test Method

[0050] With reference to the "Guideline for Laboratory Bioassay of Pesticides NY / T 1156.2-2006", the plate method was adopted: 3 mL of drug solution at each series concentration of single agents and mixtures was taken, added to 27 mL of PDA medium cooled to 45°C, to prepare drug-containing medium plates at the required final concentration. Then, 6 mm diameter mycelial plugs were taken from the edge of a 7-day-cultured colony of *Colletotrichum orbiculare*, and transferred to each series of drug-containing media with the mycelial surface facing downward, with 4 replicates for each treatment. After the treatment was completed, the plates were placed in an intelligent artificial climate incubator at 28°C for culture, the colony diameter was measured after 4 days, and the growth inhibition rate was calculated.

[0051] 5 Data Investigation and Statistical Analysis

[0052] 5.1 Investigation Method

[0053] The colony diameter was measured 4 days after the test treatment, and the growth inhibition rate (%) was calculated.

[0054] D=D1-D2

[0055] In the formula: D represents the increased diameter of the colony; D1 represents the colony diameter; D2 represents the diameter of the mycelial plug.

[0056]

[0057] In the formula: I represents the mycelial growth inhibition rate; D0 represents the increased diameter of the colony in the blank control; Dt represents the increased diameter of the colony in the pesticide treatment.

[0058] 5.2 Synergism Evaluation Method

[0059] With reference to the "Guideline for Laboratory Bioassay of Pesticides NY / T 1156.6-2006", the synergism of pesticide mixing was evaluated by the co-toxicity coefficient (CTC) method proposed by Sun & Johnson (1960), specifically, CTC ≤ 80 indicates antagonism, 80 < CTC < 120 indicates addition effect, and CTC ≥ 120 indicates synergism.

[0060]

[0061] Theoretical toxicity index of mixture (TTI) = toxicity index of pesticide A × percentage (%) of pesticide A in the mixture + toxicity index of pesticide B × percentage (%) of pesticide B in the mixture

[0062]

[0063] 5.3 Data Statistical Analysis

[0064] All experimental data were analyzed using DPS v9.50 statistical software. The mycelial growth inhibition rate (%) was calculated based on the experimental data, and the virulence regression equation, correlation coefficient (r), and EC were determined. 50 (95% confidence limit).

[0065] 6 Results Analysis and Discussion

[0066] 6.1 Efficacy Evaluation

[0067] Table 1 shows the toxicity test results of bromuconazole and azoxystrobin, as well as their different ratios, against *Agrostis chinensis*, the causal agent of watermelon anthracnose. As can be seen from Table 1, five mixtures of bromuconazole and azoxystrobin at ratios of 1:1, 1:2, 2:1, 1:4, and 4:1 all showed synergistic effects against *Agrostis chinensis*, with EC50 values ​​of 4.62, 3.57, 4.93, 3.07, and 5.31 mg / L, respectively, and co-toxicity coefficients of 123.32, 136.15, 139.19, 142.06, and 154.54, respectively. The 4:1 ratio of bromuconazole to azoxystrobin showed the most significant synergistic effect against *Agrostis chinensis*.

[0068] Table 1. Toxicity test results of the mixture of oxadiazon and bromodiphenyl ether for watermelon anthracnose.

[0069]

[0070] 6.2 Discussion and Conclusion

[0071] Indoor bioassay results showed that bromodiphenyl ether and azoxystrobin mixed in ratios of 1:1, 1:2, 2:1, 1:4, and 4:1 all exhibited synergistic effects against watermelon anthracnose pathogens, with the 4:1 ratio showing the best synergistic effect.

[0072] Application Example 3: Field Efficacy Experiment of Drug for Controlling Watermelon Anthracnose (Example 1)

[0073] Experimental basis: According to the "Good Manufacturing Practice for Pesticide Registration Trials" and "Guidelines for Field Efficacy Trials of Pesticides (II) GB / T17980.112-2000: Control of Anthracnose in Cucurbits with Fungicides".

[0074] Experimental crop: Watermelon

[0075] Target disease for prevention and control: Anthrax

[0076] 1. Basic Information of the Experiment

[0077] 1.1 Test Name

[0078] Field efficacy test of 25% azoxystrobin·bromodimethalin emulsion against watermelon anthracnose.

[0079] 1.2 Experimental Objective

[0080] The efficacy, applicable dosage, and safety of the 25% oxadiazon·bromodiflubenzuron emulsifiable concentrate provided by the applicant against watermelon anthracnose should be clarified, providing a basis for the registration and promotion of the experimental agent.

[0081] 2. Environmental and Facility Cultivation Conditions

[0082] 2.1 Test location

[0083] Jiulongpo District, Chongqing.

[0084] 2.2 Test target conditions

[0085] Anthrax (Colletotrichum biculare).

[0086] 2.3 Experimental Crops, Varieties, and Growth Status

[0087] Experimental crop: Watermelon, variety Xiangxigua 19. The plant spacing was approximately 70cm and the row spacing was approximately 200cm. The planting density was moderate, water and fertilizer management was good, weeding was timely, and the plants grew well. Sporadic disease occurred in each treatment area during the first application of pesticide.

[0088] 3. Experimental Design and Arrangement

[0089] 3.1 Test dosage and numbering

[0090] Table 2 Experimental Design of Test Reagents

[0091]

[0092] 3.2 Application Method

[0093] Spray, using 600L of pesticide solution per hectare.

[0094] The experiment involved three applications of the pesticide, on June 8, 2021, June 18, 2021, and June 28, 2021. The watermelons were in the vine-spreading stage when the pesticide was applied for the first two applications, and in the pre-flowering stage when the pesticide was applied for the third application.

[0095] 3.3 Survey methods, timing, and frequency

[0096] 3.3.1 Survey time and number of times

[0097] Pesticide damage investigation: Observe the watermelons for pesticide damage 1 day (June 9, 2021, June 19, 2021 and June 29, 2021), 3 days (June 11, 2021, June 21, 2021 and July 1, 2021), and 5 days (June 13, 2021, June 23, 2021 and July 3, 2021).

[0098] Ten days after the first application (June 18, 2021), ten days after the second application (June 28, 2021), and ten days after the third application (July 8, 2021), the occurrence of anthracnose in watermelons in each plot was investigated and recorded. A total of three investigations were conducted.

[0099] During the experiment, the effects of the test agent on other non-target organisms were observed.

[0100] 3.3.2 Survey Methodology

[0101] Disease index survey method: Five points were sampled in each community, with 3 watermelon plants at each point, and the disease status of 10 leaves on each plant was investigated from top to bottom.

[0102] Leaf damage grading method (by leaf):

[0103] Grade 0: No lesions;

[0104] Grade 1: The lesion area accounts for less than 5% of the total leaf area;

[0105] Grade 3: The lesion area accounts for 6% to 10% of the total leaf area;

[0106] Level 5: The lesion area accounts for 11% to 25% of the total leaf area;

[0107] Level 7: Lesions cover 26% to 50% of the total leaf area;

[0108] Level 9: The lesion area accounts for more than 51% of the total leaf area.

[0109] 3.3.3 Method for Calculating Drug Efficacy

[0110]

[0111]

[0112] Note: CK0—Disease index in the blank control area; PT0—Disease index in the treatment area.

[0113] 4 Results and Analysis

[0114] Table 3. Control efficacy of 25% bromuconazole·oxamethylenetetramine emulsion against watermelon anthracnose (June 18, 2021; 10 days after the first application)

[0115]

[0116] Table 4. Control efficacy of 25% bromuconazole·oxamethylenetetramine emulsion against anthracnose in watermelon (June 28, 2021; 10 days after the second application)

[0117]

[0118] Table 5. Control efficacy of 25% bromuconazole·oxamethylenetetramine emulsion against watermelon anthracnose (July 8, 2021; 10 days after the third application)

[0119]

[0120]

[0121] The experimental results showed that when 25% azoxystrobin·bromodiphenyl ether emulsifiable concentrate was applied to control watermelon anthracnose at the early stage of disease, 10 days after the first application, the disease indexes of the three concentrations of the test agent against watermelon anthracnose were 2.02, 1.71, and 1.39, respectively, with control efficacies of 62.56%, 68.35%, and 74.25%. Ten days after the second application, the disease indexes of the three concentrations of the test agent against watermelon anthracnose were 4.76, 3.91, and 2.58, respectively, with control efficacies of 67.27%, 73.12%, and 82.29%. Ten days after the third application, the disease index of watermelon anthracnose at the three concentrations were 6.64, 5.67, and 4.26, respectively, with control efficacies of 75.31%, 78.95%, and 84.18%. The control efficacies of the 300 g / hm² and 262.5 g / hm² treatments were significantly higher than those of the two control agents. All treatments significantly reduced the disease index of watermelon anthracnose compared to the water control.

[0122] Application Example 4: Efficacy Test of Drug for Controlling Watermelon Anthracnose (Example 2)

[0123] For specific experimental basis, experimental reagents and dosages, investigation methods and calculation methods, please refer to Application Example 3.

[0124] 1 Test location

[0125] Taigu District, Jinzhong City, Shanxi Province.

[0126] 2. Experimental crops, varieties, and growth conditions

[0127] The experimental crop was watermelon, and the tested variety was Extra Sweet.

[0128] Growth status: Watermelons were planted on April 12, 2021, covering an area of ​​3,000 square meters with a density of 900 plants per mu. The previous crop was corn.

[0129] 3. Application Method

[0130] 3.1 Timing and Method of Application

[0131] Apply the pesticide at the initial stage of watermelon anthracnose infection. Weigh the pesticide according to the dosage required for each treatment, dilute it with water, and spray as usual, ensuring uniform and consistent spraying without overlapping or missing areas. A blank control is sprayed with plain water.

[0132] The drug was administered three times in this trial: the first administration was on June 3, 2021; the second administration was on June 11, 2021; and the third administration was on June 18, 2021.

[0133] 3.2 Usage Capacity

[0134] The water consumption for pesticide application is 675 liters per hectare.

[0135] 3.3 Survey Time

[0136] First survey: Before the first application of pesticide on June 3, 2021, sporadic lesions appeared in the field, and the disease index was recorded as zero.

[0137] Second survey: The control effect was investigated 10 days after the last application of the pesticide on June 28, 2021, and the disease incidence was recorded according to the grading standards.

[0138] 4 Results and Analysis

[0139] Table 6. Results of the trial on the control of watermelon anthracnose using 25% azoxystrobin·bromochlorothalonil aqueous emulsion.

[0140]

[0141] The efficacy survey results of the 25% bromodiphenyl ether·bromodiphenyl ether emulsifiable concentrate applied in Example 2 10 days after application showed that: when the effective ingredient dosage of the test agent 25% bromodiphenyl ether·bromodiphenyl ether emulsifiable concentrate was 225 g / ha, 262.5 g / ha, and 300 g / ha, the control efficacy was 78.09%, 82.12%, and 86.12%, respectively; when the effective ingredient dosage of the control agent 25% bromodiphenyl ether wettable powder was 300 g / ha, the control efficacy was 76.60%; and when the effective ingredient dosage of the control agent 50% bromodiphenyl ether water-dispersible granules was 165 g / ha, the control efficacy was 71.85%.

[0142] The results, analyzed using Duncan's new multiple range method, showed that at the 0.05 level, there was no significant difference in efficacy between high and medium concentrations of the test agent 25% bromodiphenyl ether emulsion, but a significant difference compared to the low concentration and the two control agents; there was no significant difference in efficacy between medium and low concentrations of the test agent, but a significant difference compared to the two control agents; and there was no significant difference in efficacy between the low concentration of the test agent and the two control agents. At the 0.01 level, there was no significant difference in efficacy between high and medium concentrations of the test agent, but a highly significant difference between the test agent and low concentrations and the two control agents. There was no significant difference in efficacy between medium and low concentrations of the test agent and the control agent 25% bromodiphenyl ether wettable powder, but a highly significant difference between the test agent and the control agent 50% azoxystrobin water-dispersible granules. There was no significant difference in efficacy between low concentrations of the test agent and the control agents 25% bromodiphenyl ether wettable powder and 50% azoxystrobin water-dispersible granules.

[0143] The tested dosage of the agent was safe for watermelon plants and had no effect on surrounding crops or non-target organisms.

Claims

1. The use of a bactericidal composition for the prevention and control of anthracnose in watermelon, characterized in that: The effective active ingredients of the bactericidal composition are oxadiazon and bromodiphenyl ether, and the bactericidal composition contains the following components and contents: A 25% azoxystrobin·bromodiphenyl ether emulsion was prepared by comprising 5% azoxystrobin technical, 20% bromodiphenyl ether technical, 2% fatty alcohol polyoxyethylene ether, 10% phenyl methyl acetate, 15% No. 150 solvent oil, 3% castor oil polyoxyethylene ether, 1.5% polyoxyethylene-polyoxypropylene block copolymer, 5% urea, 0.1% silicone defoamer, 0.15% anhydrous citric acid, and water as the balance.

2. The use of a bactericidal composition for the prevention and control of anthracnose in watermelon, characterized in that: The effective active ingredients of the bactericidal composition are oxadiazon and bromodiphenyl ether, and the bactericidal composition contains the following components and contents: A 25% azoxystrobin·bromodiphenyl ether emulsion was prepared by comprising 5% azoxystrobin technical, 20% bromodiphenyl ether technical, 5% alkyl polyglycoside, 6% cyclohexanone, 15% No. 200 solvent oil, 4% alkylphenol polyoxyethylene ether, 3% propylene glycol, 0.2% fatty alcohol, and water as the balance.

3. The use according to claim 1 or 2, characterized in that: The effective ingredient dosage of the bactericidal composition is 225-300 grams per hectare.

Images