Medicament for preventing and treating peanut bacterial wilt as well as preparation method and application thereof

Abstract

The invention provides an agent for preventing and treating peanut bacterial wilt and a preparation method and application thereof, and belongs to the technical field of pesticide preparations, and the agent is a composite agent formed by scientifically compounding albendazole, carbendazim, kasugamycin, chlorobromoisocyanuric acid, chitosan oligosaccharide, amino-oligosaccharin, a seaweed extract, humic acid, palygorskite and trace elements. According to the invention, efficient inhibition of ralstonia solanacearum is realized, peanut system resistance is obviously activated, root development is promoted, rhizosphere microenvironment is improved, slow release of active components is realized by means of palygorskite, and the pesticide effect period is prolonged. Field trials show that the prevention and control effect reaches 84% or above, the yield increasing rate exceeds 22%, and the composition is environmentally friendly and high in safety. The bactericidal composition can be prepared into a water suspending agent or a dispersible liquid, is suitable for various application modes such as root irrigation and spraying, has the advantages of long lasting period and low resistance risk, and is suitable for large-scale popularization in green agriculture.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pesticide preparation, in particular to a medicament for preventing and treating peanut bacterial wilt and a preparation method and application thereof. BACKGROUND

[0002] Peanut bacterial wilt is a devastating soil-borne disease caused by gram-negative bacteria Ralstonia solanacearum (Ralstonia solanacearum), which has the characteristics of rapid onset, wide spread, difficult control and serious loss. The pathogen can survive in the soil for many years, invade through root wounds, block the vessels, and cause acute wilting and death of the plants. The incidence rate of the disease in a serious plot can be more than 60%, and even the yield can be completely lost. At present, the disease has occurred widely in peanut production areas in southern China and the Huang-Huai River Basin, and has become one of the main biological stress factors restricting the high and stable yield of peanuts.

[0003] At present, carbendazim, kasugamycin, thiacopper, chlorobromoisocyanuric acid, and inorganic copper preparations are commonly used for prevention and control. However, these agents have the following common problems: narrow spectrum of action or short duration: for example, although kasugamycin has good activity against Ralstonia solanacearum, it is easily photolyzed and washed away by rainwater, and the duration in the field is usually less than 7 days;

[0004] Severe drug resistance: long-term single use of carbendazim and kasugamycin has led to the development of obvious resistance of the pathogen, and the control effect in some areas has decreased to less than 40%; therefore, single chemical agents are difficult to achieve long-term, stable and sustainable control effect, and cannot achieve the control effect of more than 85% and resistance delay as achieved by the present application.

[0005] In order to improve the control effect, some products use two fungicides in combination, such as kasugamycin plus mesnigocin, and carbendazim plus mancozeb. However, these combinations are simple mixtures of the same type of agents, and the complementary mechanism is not considered, which has the following defects: lack of multi-target synergistic design, still prone to induce cross-resistance; no immune induction or nutrient promoting component is introduced, which cannot improve the plant disease resistance; poor stability of the dosage form, easy to separate, precipitate, and affect the field application effect.

[0006] In recent years, Bacillus subtilis, Bacillus amyloliquefaciens biocontrol agents, and chitosan, amino oligosaccharin plant elicitors have been used for the prevention and control of bacterial wilt. Although they are environmentally friendly, they have obvious shortcomings: slow effect and poor emergency capability: biological agents need to colonize before they can play a role, and they cannot quickly control the disease in the disease outbreak period; strong environmental dependence: affected by soil temperature, humidity, pH and organic matter content, the field control effect fluctuates significantly, usually only 30% to 50%; no direct fungicidal ability, difficult to control the disease in high incidence areas when used alone.

[0007] Bacterial wilt is closely related to soil microecological imbalance. Most existing pesticides only focus on killing pathogens, neglecting the improvement of the root environment: they do not utilize mineral carriers to adsorb pathogen toxins or slow-release active ingredients; they do not supplement humic acid, amino acids, and trace elements to promote root development; and they cannot improve soil aggregate structure or enhance plant resistance. Therefore, this paper proposes a pesticide for controlling peanut bacterial wilt, its preparation method, and its application. Summary of the Invention

[0008] The purpose of this invention is to address the problems raised in the existing background technology. To achieve the above-mentioned objective, this invention provides the following technical solution: an agent for controlling peanut bacterial wilt, comprising, by weight, the following components: 5-15 parts albendazole, 10-20 parts carbendazim, 3-8 parts chitosan oligosaccharide, 5-12 parts seaweed extract, 6-15 parts palygorskite mineral, 4-10 parts humic acid, 3-8 parts chlorpyrifos, 2-6 parts kasugamycin, 4-10 parts chlorobromoisocyanuric acid, 2-7 parts amino oligosaccharide, 3-9 parts complex plant-derived amino acids, 1-4 parts zinc sulfate, 0.5-3 parts boric acid, 2-6 parts adjuvants, and deionized water to a total of 100 parts; wherein the adjuvants include emulsifiers and thickeners, with the emulsifier used at 0.5%-2% of the total mass of all materials, and the thickener used at 0.3%-1.5% of the total mass of all materials.

[0009] As a preferred technical solution of the present invention, the palygorskite mineral is activated as follows: natural attapulgite is treated with 2 mol / L hydrochloric acid at 70°C for 2 hours, then washed with water until neutral after solid-liquid separation, dried at 60°C, and pulverized through a 200-mesh sieve. The resulting activated palygorskite has a higher specific surface area and ion adsorption capacity, and can effectively adsorb pathogenic toxins and slowly release active ingredients.

[0010] As a preferred technical solution of the present invention, the chitosan is a low-viscosity chitosan with a degree of deacetylation ≥85% and a viscosity ≤60mPa·s, which is used to assist chitosan oligosaccharides and amino oligosaccharides in inducing plant systematic resistance (SAR), and its addition amount is 1 to 3 parts;

[0011] The potassium humate contains ≥55% fulvic acid and has a pH of 5.8–6.8, serving as an organic carrier to enhance the balance of rhizosphere microorganisms.

[0012] The free humic acid content is ≥75%, and the addition amount is 2-4 parts, which synergistically improves the soil aggregate structure.

[0013] As a preferred technical solution of the present invention, the emulsifiers NP-10 and AEO-9 in the auxiliary agent can be used alone or in combination at a mass ratio of 1:1. NP-10 is preferred, with an HLB value of 13.0 to 13.5, and a moderate balance between hydrophilicity and lipophilicity, which is conducive to the formation of a stable emulsion.

[0014] The thickener, xanthan gum, is food grade with a viscosity ≥1200 mPa·s (1% aqueous solution, 25℃). After addition, it increases the suspension rate of the formulation to ≥90% and prevents sedimentation and agglomeration.

[0015] As a preferred technical solution of the present invention, the seaweed extract is prepared by the following process: after pulverizing dried seaweed, add 5 times the amount of deionized water, add cellulase (3000U / g) and pectinase (2000U / g), enzymatically hydrolyze at pH 4.8 and 50℃ for 4 hours, centrifuge to collect the supernatant, concentrate to a solid content ≥40%, and spray dry to obtain powder;

[0016] The resulting extract is rich in alginate, fucoidan, and plant hormone analogs (such as auxins and cytokinins), which can promote root development and enhance stress resistance.

[0017] A method for preparing an agent to control bacterial wilt of peanuts includes the following steps:

[0018] Step 1, Aqueous phase preparation: Add 40-50 parts of deionized water to a stirred tank, then add albendazole, carbendazim, chlorpyrifos, kasugamycin, and chlorobromoisocyanuric acid in sequence. Heat to 40°C and stir to dissolve for 30 minutes. Then add 1.8 parts of Tween-80 and 2.5 parts of PVP K30, and continue stirring until completely dissolved to form a transparent or slightly turbid aqueous solution.

[0019] Step 2, Solid-phase dispersion: In a separate mixing tank, add 11 parts palygorskite minerals, 7 parts humic acid, 6 parts chitosan oligosaccharide, 5 parts amino oligosaccharide, 6 parts complex plant-derived amino acids, 2.5 parts zinc sulfate, 1.5 parts boric acid, 2 parts chitosan, and 3 parts fulvic acid, and mix well.

[0020] Step 3, preparation of suspension: Add 30-35 parts of deionized water to the mixture in step 2, disperse at high speed shearing speed of 8000 rpm for 30 minutes to form a uniform suspension;

[0021] Step 4, Additives: Add 1.5% of NP-10 emulsifier, 0.8% of xanthan gum, and 0.25 parts of Kathon preservative to the suspension from Step 3, and continue shearing for 15 minutes.

[0022] Step 5, Homogenization and Emulsification: Slowly add the aqueous phase obtained in Step 1 to the suspension system in Step 4, and homogenize it in a homogenizer at 10,000 rpm for 30 minutes to form a uniform and fine emulsion suspension.

[0023] Step 6, Filtration and Filling: After filtration through a 100-mesh sieve, the pH value is tested to be 6.2-6.8. After adjustment to the qualified range, the product is filled into light-proof plastic bottles and sealed for storage. The resulting product is a grayish-white to light brown uniform suspension with no obvious stratification or sedimentation.

[0024] A method for preparing an agent to prevent and control bacterial wilt of peanuts, wherein the temperature is controlled at 25-40℃ throughout the preparation process to avoid degradation of active ingredients due to high temperature;

[0025] After homogenization, the particle size of the product is D90≤8.0μm, which is determined by a laser particle size analyzer;

[0026] The suspension rate was determined according to GB / T 14825~2006, and the suspension rate was ≥92% after 24 hours.

[0027] Thermal storage stability test: After being placed in a constant temperature chamber at 54±2℃ for 14 days, the decomposition rate of the effective ingredients was ≤5%, with no clumping or stratification.

[0028] As a preferred technical solution of the present invention, the pesticide for controlling peanut bacterial wilt is a uniform suspension with no visible particles or floating oil; the pH value of the pesticide for controlling peanut bacterial wilt is 6.0-7.0 (25℃); the viscosity of the pesticide for controlling peanut bacterial wilt is 800-1500 mPa·s (25℃, rotational viscometer, 60 rpm); the pourability of the pesticide for controlling peanut bacterial wilt is ≥90%; the wet sieve test of the pesticide for controlling peanut bacterial wilt shows that it passes through a 75μm standard sieve with a residue of ≤0.3%; the low-temperature stability of the pesticide for controlling peanut bacterial wilt is such that after being stored at 0±2℃ for 7 days, no crystallization or precipitation occurs after returning to room temperature; and the deviation of the effective ingredient content of the pesticide for controlling peanut bacterial wilt is such that the measured value of each main drug deviates from the labeled amount within ±5%.

[0029] The application of a pesticide for controlling bacterial wilt of peanuts involves diluting the pesticide 400 times with water and applying it by root irrigation. Each peanut plant is irrigated with 100-150 mL of the pesticide solution, and the amount of pesticide solution applied per acre is 50 L.

[0030] The application of pesticides should be done during the peanut seedling stage (3-4 leaf stage), the beginning of flowering, and the early stage of pegging, for a total of 3 applications;

[0031] Alternatively, foliar spraying can be carried out at the early stage of bacterial wilt, spraying until the leaves are wet and dripping with liquid, and repeating 2-3 times at 7-10 day intervals; after application, keep the soil moist to avoid drought affecting the efficacy of the medicine.

[0032] Application of a pesticide for controlling peanut bacterial wilt, wherein the pesticide controls peanut bacterial wilt through multiple mechanisms in a synergistic manner: chemical fungicide: albendazole, carbendazim, chlorpyrifos, and chlorobromoisocyanuric acid directly kill or inhibit the bacterial wilt fungus (Ralstonia solanacearum).

[0033] Biologically induced resistance: Chitosan oligosaccharides, amino oligosaccharides, and seaweed extracts activate plant defense genes (such as PAL, POD, and SOD) to induce systemic resistance (SAR); Nutrition and root promotion: Humic acid, seaweed extracts, amino acids, and Zn / B trace elements promote root development and improve plant vigor; Soil microecological regulation: Palaequa calcite adsorbs pathogens and their toxins, slowly releases active ingredients, and prolongs the duration of effectiveness.

[0034] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0035] This invention's agent contains multiple fungicides with different mechanisms of action, including albendazole, carbendazim, kasugamycin, and chlorobromoisocyanuric acid. These components act on the microtubules, ribosomes, cell membranes, and protein synthesis systems of pathogens, respectively, avoiding the risk of resistance caused by single-target action. Simultaneously, chitosan oligosaccharides and amino oligosaccharide elicitors are introduced to activate the plant's own defense system (SAR) to achieve non-fungal resistance, further reducing evolutionary pressure on pathogens and extending the agent's lifespan.

[0036] This invention contains plant immune inducers rich in chitosan oligosaccharides, amino oligosaccharides, and seaweed extracts. These inducers significantly activate the activity of phenylalanine ammonia-lyase (PAL), superoxide dismutase (SOD), and peroxidase (POD) defense enzymes in peanuts, promoting lignin and phytoalexin accumulation, strengthening cell wall structure, and forming a durable disease-resistant barrier. Pot experiments showed that the treatment group exhibited a 65.7% increase in SOD activity and an 81.2% increase in POD activity, significantly enhancing the plant's stress resistance.

[0037] The agent of this invention contains humic acid, fulvic acid, compound plant-derived amino acids, zinc sulfate, boric acid, organic nutrients, and trace elements, which can effectively improve the nutritional environment of peanut roots and promote root growth. Field observations show that after application, the number of white roots in peanuts increases, root nodules become more abundant, stems become thicker, and leaves become dark green. In pot experiments, the fresh weight of roots increased by 74.7%, and the number of pods per plant increased by 29.2%, laying a physiological foundation for high and stable yields.

[0038] This invention uses activated palygorskite minerals as a functional carrier, which has a high specific surface area (≥200m²). 2 With a cation exchange capacity of ≥25 meq / 100g, it can effectively adsorb bacterial wilt pathogens and their secreted toxins, reducing the colonization of pathogens in the rhizosphere; at the same time, it can slowly release kasugamycin and chitosan oligosaccharide active ingredients through ion exchange, prolonging the efficacy period to 15-20 days, reducing the frequency of application, and lowering labor costs.

[0039] The aqueous suspension (SC) or dispersible liquid (SL) prepared by this invention exhibits excellent physical stability: suspension rate ≥90%, no stratification after 24 hours, and active ingredient decomposition rate ≤5% after heat storage (54℃, 14 days). The emulsifier (NP-10) and thickener (xanthan gum) work synergistically to ensure uniform dispersion of the solution, making it suitable for various application methods including root irrigation, drip irrigation, and foliar spraying. It also shows good compatibility with common neutral pesticides and foliar fertilizers, facilitating integrated field application.

[0040] In areas prone to bacterial wilt, three consecutive applications of this agent resulted in a yield of 352.1 kg per mu (approximately 0.067 hectares), an increase of 65.4 kg per mu compared to the control group treated with water, representing a yield increase of 22.8%. This was also an increase of 33.7 kg per mu compared to conventional pesticide treatments, demonstrating significant economic benefits. Furthermore, the peanut kernels were plump, with a high shelling percentage, improving marketability and indicating promising market prospects.

[0041] The preparation method of this invention has a clear process flow, is simple to operate, requires no special equipment, and can be mass-produced on conventional pesticide formulation production lines. The raw materials are widely available, the cost is controllable, and it is suitable for large-scale application. Attached Figure Description

[0042] Figure 1 This invention provides a schematic diagram of the key raw material data and ingredient proportions.

[0043] Figure 2 This is a schematic diagram illustrating the preparation of seaweed extract provided by the present invention;

[0044] Figure 3 This is a schematic diagram of the pharmaceutical preparation process provided by the present invention. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention.

[0046] Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely illustrates some embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention. It should be noted that, in the absence of conflict, the embodiments and features and technical solutions in the embodiments of the present invention can be combined with each other. It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0047] Example 1: An agent for controlling bacterial wilt of peanuts, comprising the following components by weight: 5-15 parts albendazole, 10-20 parts carbendazim, 3-8 parts chitosan oligosaccharide, 5-12 parts seaweed extract, 6-15 parts palygorskite mineral, 4-10 parts humic acid, 3-8 parts chlorpyrifos, 2-6 parts kasugamycin, 4-10 parts chlorobromoisocyanuric acid, 2-7 parts amino oligosaccharide, 3-9 parts compound plant-derived amino acids, 1-4 parts zinc sulfate, 0.5-3 parts boric acid, 2-6 parts adjuvants, and deionized water to a total of 100 parts; wherein the adjuvants include emulsifiers and thickeners, with the emulsifier accounting for 0.5%-2% of the total mass of all materials, and the thickener accounting for 0.3%-1.5% of the total mass of all materials.

[0048] The preferred composition is as follows: albendazole 10 parts, carbendazim 12 parts, chitosan oligosaccharide 5 parts, seaweed extract 8 parts, palygorskite mineral 12 parts, humic acid 6 parts, chlorpyrifos 7 parts, kasugamycin 5 parts, chlorobromoisocyanuric acid 6 parts, amino oligosaccharide 4 parts, complex plant-derived amino acids 6 parts, zinc sulfate 3 parts, boric acid 2.5 parts, additives 4 parts, and deionized water to a total of 100 parts. The additives include emulsifiers and thickeners; the emulsifier is used at 0.5%–2% of the total mass of all materials, and the thickener is used at 0.3%–1.5% of the total mass of all materials.

[0049] Palaequa calcite minerals were activated as follows: natural attapulgite was treated with 2 mol / L hydrochloric acid at 70°C for 2 hours, then separated into solid and liquid, washed with water until neutral, dried at 60°C, and pulverized through a 200-mesh sieve. The resulting activated palaequa calcite has a higher specific surface area and ion adsorption capacity, and can effectively adsorb pathogenic toxins and slowly release active ingredients.

[0050] Chitosan is a low-viscosity chitosan with a degree of deacetylation ≥85% and a viscosity ≤60mPa·s. It is used to assist chitosan oligosaccharides and amino oligosaccharides in inducing plant systematic resistance (SAR). The amount added is 1 to 3 parts.

[0051] Potassium humate contains ≥55% fulvic acid and has a pH of 5.8–6.8, serving as an organic carrier to enhance the balance of rhizosphere microorganisms;

[0052] The free humic acid content is ≥75%, and the addition amount is 2-4 parts, which synergistically improves the soil aggregate structure.

[0053] The emulsifiers NP-10 and AEO-9 in the additives can be used alone or in combination at a mass ratio of 1:1. NP-10 is preferred, with an HLB value of 13.0 to 13.5 and a moderate balance of hydrophilicity and lipophilicity, which is conducive to the formation of a stable emulsion.

[0054] The thickener xanthan gum is food grade with a viscosity ≥1200 mPa·s (1% aqueous solution, 25℃). After addition, it increases the suspension rate of the formulation to ≥90% and prevents sedimentation and agglomeration.

[0055] Seaweed extract is prepared by the following process: dried seaweed is pulverized, 5 times the amount of deionized water is added, cellulase (3000U / g) and pectinase (2000U / g) are added, and enzymatic hydrolysis is carried out at pH 4.8 and 50℃ for 4 hours. The supernatant is collected by centrifugation, concentrated to a solid content of ≥40%, and spray-dried to obtain powder.

[0056] The resulting extract is rich in alginate, fucoidan, and plant hormone analogs (such as auxins and cytokinins), which can promote root development and enhance stress resistance.

[0057] Example 2: A method for preparing an agent to control bacterial wilt of peanuts, comprising the following steps:

[0058] Step 1, Aqueous phase preparation: Add 40-50 parts of deionized water to a stirred tank, then add albendazole, carbendazim, chlorpyrifos, kasugamycin, and chlorobromoisocyanuric acid in sequence. Heat to 40°C and stir to dissolve for 30 minutes. Then add 1.8 parts of Tween-80 and 2.5 parts of PVP K30, and continue stirring until completely dissolved to form a transparent or slightly turbid aqueous solution.

[0059] Step 2, Solid-phase dispersion: In a separate mixing tank, add 11 parts palygorskite minerals, 7 parts humic acid, 6 parts chitosan oligosaccharide, 5 parts amino oligosaccharide, 6 parts complex plant-derived amino acids, 2.5 parts zinc sulfate, 1.5 parts boric acid, 2 parts chitosan, and 3 parts fulvic acid, and mix well.

[0060] Step 3, preparation of suspension: Add 30-35 parts of deionized water to the mixture in step 2, disperse at high speed shearing speed of 8000 rpm for 30 minutes to form a uniform suspension;

[0061] Step 4, Additives: Add 1.5% of NP-10 emulsifier, 0.8% of xanthan gum, and 0.25 parts of Kathon preservative to the suspension from Step 3, and continue shearing for 15 minutes.

[0062] Step 5, Homogenization and Emulsification: Slowly add the aqueous phase obtained in Step 1 to the suspension system in Step 4, and homogenize it in a homogenizer at 10,000 rpm for 30 minutes to form a uniform and fine emulsion suspension.

[0063] Step 6, Filtration and Filling: After filtration through a 100-mesh sieve, the pH value is tested to be 6.2-6.8. After adjustment to the qualified range, the product is filled into light-proof plastic bottles and sealed for storage. The resulting product is a grayish-white to light brown uniform suspension with no obvious stratification or sedimentation.

[0064] A method for preparing an agent to prevent and control bacterial wilt of peanuts, wherein the temperature is controlled at 25-40℃ throughout the preparation process to avoid degradation of active ingredients due to high temperature;

[0065] After homogenization, the particle size of the product is D90≤8.0μm, which is determined by a laser particle size analyzer;

[0066] The suspension rate was determined according to GB / T 14825~2006, and the suspension rate was ≥92% after 24 hours.

[0067] Thermal storage stability test: After being placed in a constant temperature chamber at 54±2℃ for 14 days, the decomposition rate of the effective ingredients was ≤5%, with no clumping or stratification.

[0068] The pesticide for controlling peanut bacterial wilt is a uniform suspension with no visible particles or floating oil. Its pH value is 6.0–7.0 (25℃). Its viscosity is 800–1500 mPa·s (25℃, rotational viscometer, 60 rpm). Its pourability is ≥90%. In a wet sieve test, it passes through a 75 μm standard sieve with a residue of ≤0.3%. It exhibits low-temperature stability after being stored at 0±2℃ for 7 days and then restored to room temperature without crystallization or precipitation. The deviation in the content of the active ingredient is within ±5% of the stated value for each active ingredient.

[0069] The application of a pesticide for controlling bacterial wilt of peanuts involves diluting the pesticide 400 times with water and applying it by root irrigation. Each peanut plant is irrigated with 100-150 mL of the pesticide solution, and the amount of pesticide solution applied per acre is 50 L.

[0070] The application of pesticides should be done during the peanut seedling stage (3-4 leaf stage), the beginning of flowering, and the early stage of pegging, for a total of 3 applications;

[0071] Alternatively, foliar spraying can be carried out at the early stage of bacterial wilt, spraying until the leaves are wet and dripping with liquid, and repeating 2-3 times at 7-10 day intervals; after application, keep the soil moist to avoid drought affecting the efficacy of the medicine.

[0072] Application of a pesticide for controlling peanut bacterial wilt: A pesticide for controlling peanut bacterial wilt synergistically controls peanut bacterial wilt through multiple mechanisms: Chemical fungicide: Albendazole, carbendazim, chlorpyrifos, and chlorobromoisocyanuric acid directly kill or inhibit the bacterial wilt fungus (Ralstonia solanacearum).

[0073] Biologically induced resistance: Chitosan oligosaccharides, amino oligosaccharides, and seaweed extracts activate plant defense genes (such as PAL, POD, and SOD) to induce systemic resistance (SAR); Nutrition and root promotion: Humic acid, seaweed extracts, amino acids, and Zn / B trace elements promote root development and improve plant vigor; Soil microecological regulation: Palaequa calcite adsorbs pathogens and their toxins, slowly releases active ingredients, and prolongs the duration of effectiveness.

[0074] Experimental Example 1: Indoor toxicity test – Inhibitory effect of compound agent on Ralstonia solanacearum causal agent

[0075] 1. Test materials

[0076] Test strain: Ralstonia solanacearum, the pathogen of bacterial wilt of peanut (laboratory preservation, serial number RS-2024)

[0077] Test reagent: The composite reagent of the present invention (prepared according to the proportions in claim 1, number FZ-2025)

[0078] Control agents: 50% chlorobromoisocyanuric acid wettable powder, 70% carbendazim wettable powder

[0079] Culture medium: NA medium (nutrient agar)

[0080] 2. Test Methods

[0081] The mycelial growth inhibition method (suitable for inhibiting bacterial spread) was used. The agent was diluted into five concentration gradients (100, 200, 400, 800, and 1600 mg / L), added to sterilized NA medium cooled to 45°C, mixed well, and poured into Petri dishes. A 6 mm diameter mycelial cake was inoculated in the center of each plate, and the plates were incubated at 28°C for 48 hours. The colony diameter was measured, and the inhibition rate was calculated.

[0082] 3. Calculation formula

[0083] Inhibition rate = {(CT) / C} * 100

[0084] Where C represents the colony diameter of the control group and T represents the colony diameter of the treatment group.

[0085] 4. Results

[0086]

[0087]

[0088] Conclusion: The compound agent of this invention has a significant inhibitory effect on Ralstonia solanacearum, EC 100%. 50 The concentration was 112.4 mg / L, significantly lower than that of a single agent, indicating a significant synergistic effect of multiple components.

[0089] Experimental Example 2: Pot Experiment – ​​Control Effect and Growth Promotion Effect on Peanut Bacterial Wilt

[0090] 1. Test materials

[0091] Test crop: Peanut variety "Yuhua 15"

[0092] Test soil: Sandy loam soil artificially inoculated with bacterial wilt pathogen (inoculum count 10). 6 CFU / g)

[0093] Test reagent: The compound reagent of this invention (diluted 400 times)

[0094] Control agents: 50% carbendazim WP (500x dilution), water

[0095] Experimental design: randomized block design, with 3 replicates per treatment and 4 plants per pot.

[0096] 2. Application method

[0097] Apply the solution to the roots of the peanut plant during the 3-leaf stage, using 100 mL of the solution per pot, once every 10 days, for a total of 2 applications.

[0098] 3. Survey Indicators

[0099] Plant height, root length, and fresh weight growth indicators

[0100] 4. Disease grading criteria

[0101] Level 0: Asymptomatic

[0102] Grade 1: Leaves wilt slightly, wilting at midday and recovering in the morning and evening.

[0103] Grade 3: 1-2 leaves permanently wilted

[0104] Level 5: The entire plant is wilted, but not dead.

[0105] Level 7: Plant died

[0106] 5. Results (30 days after application)

[0107]

[0108] Conclusion: The agent of this invention significantly reduces the incidence and disease index, with a control effect of 84.2%, while significantly promoting peanut growth, developing a strong root system, and resulting in robust plants.

[0109] Experimental Example 3: Field Plot Trial – Practical Application Effects in Areas with High Incidence of Bacterial Wilt

[0110] 1. Test site

[0111] Zhengyang County, Zhumadian City, Henan Province (an area where bacterial wilt occurs year-round, soil pH 6.2, sandy loam soil)

[0112] 2. Experimental Design

[0113] Tested variety: Yuhua 37

[0114] Test area: 20m² per plot 2 3 repetitions, randomized block arrangement

[0115] deal with:

[0116] A: The compound agent of this invention is diluted 400 times and applied as a root drench once each during the seedling stage, flowering stage, and pegging stage (50L / acre).

[0117] B: 50% chlorobromoisocyanuric acid WP 600x + 70% carbendazim WP 800x, foliar spray, once every 7 days, for a total of 3 times.

[0118] C: Water Comparison

[0119] 3. Application method

[0120] Group A was treated by root irrigation, 100-150 mL per plant; Group B was treated by foliar spraying until the leaves were moist.

[0121] 4. Survey and Findings

[0122] Incidence rate and disease index

[0123] Number of fruits per plant, weight of 100 fruits, yield per acre

[0124] Production increase rate calculation

[0125] 5. Summary of Results

[0126]

[0127] 6. Observation Records

[0128] Group A peanuts have many white roots, abundant root nodules, thick stems, and dark green leaves;

[0129] Although Group B had some preventive effect, sporadic diseased plants still appeared in the later stages;

[0130] No pesticide damage was observed in Group A, and there were no adverse effects on surrounding crops or non-target organisms such as bees.

[0131] Conclusion: The compound agent of this invention showed excellent disease prevention and yield-increasing effects under field conditions, with a control effect of 84.6% and a yield increase of 65.4 kg per mu, representing a yield increase rate of 22.8%, which is significantly better than conventional control programs.

[0132] Experiment Summary

[0133] Through three-level trials—indoor, potted, and field—the compound agent of this invention has the following advantages:

[0134] Highly effective and broad-spectrum: Strong inhibitory effect against bacterial wilt pathogens, EC... 50 As low as 112.4 mg / L;

[0135] Synergistic effect: The combination of multiple bactericides and immune inducers significantly enhances the preventive effect;

[0136] Promotes growth and resistance to adverse conditions: Significantly promotes root development and enhances the plant's disease resistance.

[0137] Long duration of effect: The sustained-release effect of palygorskite allows the drug effect to last for more than 15 days;

[0138] Safe and environmentally friendly: No obvious pesticide damage, environmentally friendly, and suitable for the promotion of green agriculture.

[0139] Experiment Example 4: Verification Experiment of Synergistic Effect of Drug Formulation

[0140] I. Experimental Objective

[0141] The synergistic effect among key components (such as albendazole, carbendazim, kasugamycin, and chitosan oligosaccharide) in the compound agent of this invention was verified, and the significant improvement in antibacterial activity and field control efficacy of multiple combinations compared to single or pairwise combinations was clarified, proving the rationality and advancement of the formulation design.

[0142] II. Test Materials

[0143] Test strain: Ralstonia solanacearum (RS-2024), the pathogen of bacterial wilt of peanut.

[0144] Test reagents:

[0145] The complete formulation of this invention (FZ-2025, prepared according to the proportions in claim 1)

[0146] Combination A: Albendazole + Carbendazim (5:10)

[0147] Combination B: Kasugamycin + Chlorobromoisocyanuric acid (3:6)

[0148] Combination C: Chitosan oligosaccharide + seaweed extract + humic acid (5:8:6)

[0149] Single-dose control: Albendazole, Carbendazim, Kasugamycin, Chitosan oligosaccharide

[0150] Culture medium: NA nutrient agar medium

[0151] Instruments and Equipment: Clean bench, constant temperature incubator, vernier calipers, microplate reader, laser particle size analyzer. III. Experimental Methods

[0152] 1. Indoor Co-toxicity assay – Co-Toxicity Coefficient (CTC) method

[0153] The inhibition rate of each agent combination against *Ralstonia solanacearum* was determined using the colony diameter method, and the co-toxicity factor (CTC) was calculated to determine the synergistic effect type.

[0154] CTC < 80: Antagonistic effect

[0155] 80≤CTC≤120: Additive effect

[0156] CTC>120: Synergistic effect

[0157] Test concentration: Each drug and its combination are diluted to a total effective ingredient concentration of 200 mg / L (calculated based on the effective dose).

[0158] 2. Potted plant synergistic control effect test

[0159] Peanut variety tested: Yuhua 15

[0160] Soil: Artificial inoculation with bacterial wilt pathogen (10) 6 CFU / g)

[0161] Treatment settings (3 replicates per treatment, 4 plants per pot):

[0162]

[0163] Application time: 3-leaf stage, early flowering stage, 10-day interval.

[0164] Survey indicators: Incidence rate, disease index, control effect, root fresh weight, SOD / POD enzyme activity. IV. Experimental results.

[0165] 1. Results of indoor synergistic toxicity assay (200 mg / L, 48 h)

[0166]

[0167]

[0168] Note: All pairwise combinations had CTC > 120, indicating significant synergistic effects; in particular, the combinations of kasugamycin + chlorobromoisocyanuric acid and chitosan oligosaccharide + seaweed extract had CTCs of 124.2 and 128.1, respectively, demonstrating the complementarity of the bactericidal and inducing pathways.

[0169] 2. Comparison of control efficacy and growth indicators in pot experiments

[0170]

[0171] V. Data Analysis and Conclusions

[0172] Synergistic effects between chemical components:

[0173] Both albendazole and carbendazim act on tubulin, but their sites of action differ slightly. Combined use can delay the development of resistance, with a CTC of 120.1, reaching a synergistic level.

[0174] Kasugamycin (inhibits protein synthesis) and chlorobromoisocyanuric acid (disrupts cell membranes) have complementary mechanisms, with a CTC of 124.2, significantly enhancing its broad-spectrum bactericidal activity.

[0175] Synergistic effect of bio-inducible components:

[0176] Both chitosan oligosaccharide and seaweed extract can activate plant defense systems. The former mainly works through receptor recognition, while the latter provides hormone signals. The combined use of the two significantly enhances the activity of SOD and POD enzymes, with CTC=128.1, demonstrating the synergistic effect of signaling pathways.

[0177] Synergistic advantages of the entire formula:

[0178] The incidence rate of T1 (complete formula) was only 13.3%, significantly lower than that of T5 (23.3%), indicating that the integration of the three modules of chemical sterilization, biological induction and nutrient slow release produced a systemic synergy of "1+1+1>3".

[0179] The fresh weight of the roots increased by 74.7%, and the SOD activity increased by 65.7%, indicating that the plant's disease resistance was significantly enhanced.

[0180] Synergistic effect of palygorskite and humic acid:

[0181] Palaequa regia adsorbs pathogens and slowly releases active ingredients, prolonging the efficacy of the medicine; humic acid improves the rhizosphere environment, promotes the colonization of beneficial bacteria, and indirectly enhances the preventive effect.

[0182] VI. Conclusion

[0183] The compound agent of this invention achieves the following synergistic effect through scientific formulation:

[0184] Synergistic bactericidal effect: The combination of multi-target chemical agents enhances antibacterial strength and delays drug resistance;

[0185] Synergistic induction: Chitosan oligosaccharide and seaweed extract synergistically activate plant systemic resistance (SAR);

[0186] Functional modules work together: the four modules of chemical control, biological induction, nutrient promotion and soil improvement support each other to form a closed-loop control system;

[0187] Carrier enhancement: Palaequa calcite and humic acid improve the stability and duration of action of the drug.

[0188] The formulation of this invention is not a simple superposition of components, but a rational design based on complementary mechanisms of action, which has significant synergistic effects and is its core technical advantage in effectively preventing and controlling peanut bacterial wilt.

[0189] The above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described herein. Although the present invention has been described in detail with reference to the above embodiments, the present invention is not limited to the specific embodiments described above. Therefore, any modifications or substitutions to the present invention, as well as all technical solutions and improvements that do not depart from the spirit and scope of the invention, are covered within the scope of the claims of the present invention.

Claims

1. A pesticide for controlling bacterial wilt of peanuts, characterized in that: The product comprises the following components by weight: 5-15 parts albendazole, 10-20 parts carbendazim, 3-8 parts chitosan oligosaccharide, 5-12 parts seaweed extract, 6-15 parts palygorskite mineral, 4-10 parts humic acid, 3-8 parts chlorpyrifos, 2-6 parts kasugamycin, 4-10 parts chlorobromoisocyanuric acid, 2-7 parts amino oligosaccharide, 3-9 parts complex plant-derived amino acids, 1-4 parts zinc sulfate, 0.5-3 parts boric acid, 2-6 parts adjuvants, and deionized water to a total of 100 parts; wherein the adjuvants include emulsifiers and thickeners, with the emulsifier accounting for 0.5%-2% of the total mass of all materials and the thickener accounting for 0.3%-1.5% of the total mass of all materials.

2. The agent for controlling bacterial wilt of peanuts according to claim 1, characterized in that: The palygorskite minerals were activated by the following process: natural attapulgite clay was treated with 2 mol / L hydrochloric acid at 70°C for 2 hours, then separated into solid and liquid components, washed with water until neutral, dried at 60°C, and pulverized through a 200-mesh sieve.

3. The agent for controlling bacterial wilt of peanuts according to claim 1, characterized in that: Chitosan is a low-viscosity chitosan with a degree of deacetylation ≥85% and a viscosity ≤60mPa·s. It is used to assist chitosan oligosaccharides and amino oligosaccharides in inducing plant systemic resistance. The amount added is 1 to 3 parts. The potassium humate contains ≥55% fulvic acid, has a pH of 5.8–6.8, and contains ≥75% free fulvic acid. The amount added is 2–4 parts.

4. The agent for controlling bacterial wilt of peanuts according to claim 1, characterized in that: The emulsifiers NP-10 and AEO-9 are used alone or in combination at a mass ratio of 1:1; the thickener xanthan gum has a viscosity ≥1200 mPa·s.

5. The agent for controlling bacterial wilt of peanuts according to claim 1, characterized in that: The seaweed extract is prepared by the following process: dried seaweed is pulverized, 5 times the amount of deionized water is added, 3000 U / g of cellulase and 2000 U / g of pectinase are added, and enzymatic hydrolysis is carried out at pH 4.8 and 50℃ for 4 hours. The supernatant is collected by centrifugation, concentrated to a solid content of ≥40%, and spray-dried to obtain powder. The obtained extract contains alginate, fucoidan, and plant hormones.

6. A method for preparing an agent for controlling bacterial wilt of peanuts according to any one of claims 1 to 5, characterized in that: Includes the following steps: Step 1, Aqueous phase preparation: Add 40-50 parts of deionized water to a stirred tank, then add albendazole, carbendazim, chlorpyrifos, kasugamycin, and chlorobromoisocyanuric acid in sequence. Heat to 40°C and stir to dissolve for 30 minutes. Then add 1.8 parts of Tween-80 and 2.5 parts of PVP K30, and continue stirring until completely dissolved to form a transparent or slightly turbid aqueous solution. Step 2, Solid-phase dispersion: In a separate mixing tank, add 11 parts palygorskite minerals, 7 parts humic acid, 6 parts chitosan oligosaccharide, 5 parts amino oligosaccharide, 6 parts complex plant-derived amino acids, 2.5 parts zinc sulfate, 1.5 parts boric acid, 2 parts chitosan, and 3 parts fulvic acid, and mix well. Step 3, preparation of suspension: Add 30-35 parts of deionized water to the mixture in step 2, disperse at high speed shearing speed of 8000 rpm for 30 minutes to form a uniform suspension; Step 4, Additives: Add 1.5% of NP-10 emulsifier, 0.8% of xanthan gum, and 0.25 parts of Kathon preservative to the suspension from Step 3, and continue shearing for 15 minutes. Step 5, Homogenization and Emulsification: Slowly add the aqueous phase obtained in Step 1 to the suspension system in Step 4, and homogenize it in a homogenizer at 10,000 rpm for 30 minutes to form a uniform and fine emulsion suspension. Step 6, Filtration and Filling: After filtration through a 100-mesh sieve, the pH value is tested to be 6.2-6.

8. After adjustment to the qualified range, the product is filled into light-proof plastic bottles and sealed for storage. The resulting product is a grayish-white to light brown uniform suspension with no obvious stratification or sedimentation.

7. The method for preparing an agent for controlling bacterial wilt of peanuts according to claim 6, characterized in that: The temperature was controlled at 25–40℃ throughout the preparation process; after homogenization, the particle size of the product D90 ≤ 8.0 μm.

8. The method for preparing an agent for controlling bacterial wilt of peanuts according to claim 7, characterized in that: pH value of the agent: 6.0~7.0; viscosity of the agent: 800~1500mPa·s.

9. The application of an agent for controlling peanut bacterial wilt according to any one of claims 1 to 5 in the control of peanut bacterial wilt, characterized in that: Dilute the pesticide with water 400 times and apply it by root irrigation. Apply 100-150 mL of pesticide solution to each peanut plant, and 50 L of pesticide solution per acre. Apply the pesticide during the peanut seedling stage, the beginning of flowering, and the early stage of pegging, for a total of 3 applications. At the early stage of bacterial wilt, spray the leaves until they are wet and dripping with liquid, and spray 2-3 times at 7-10 day intervals.

10. The application of the agent for controlling peanut bacterial wilt according to claim 9 in the control of peanut bacterial wilt, characterized in that: The aforementioned agent for controlling peanut bacterial wilt utilizes multiple mechanisms to synergistically control the disease: chemical fungicide: albendazole, carbendazim, chlorpyrifos, and chlorobromoisocyanuric acid directly kill or inhibit the bacterial wilt pathogen; biologically induced resistance: chitosan oligosaccharides, amino oligosaccharides, and seaweed extracts activate plant defense genes and induce systemic resistance; nutrition and root promotion: humic acid, seaweed extracts, amino acids, and Zn / B trace elements promote root development.

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