Plant disease control composition and plant disease control method

Abstract

The invention provides a plant disease control composition, which comprises the following components: 8-25% of sophora alopecuroide total alkaloids, the sophora alopecuroide total alkaloids comprise sophocarpidine, oxymatrine and sophocarpidine, the mass ratio of the sophocarpidine to the oxymatrine to the sophocarpidine is (5-7): (2-3): (1-2); 10%-35% of tea tree oil; 3%-15% of a natural synergist; 5%-18% of a natural emulsifier; 12%-30% of a food-grade solvent; and the balance of deionized water. According to the composition for preventing and treating the plant diseases, the sophora alopecuroide total alkaloids and the high-purity tea tree oil in a specific proportion form a synergistic antibacterial-antiviral system, so that the composition generates synergistic control on fungal diseases and viral diseases, the limitation of narrow action spectrum of a single plant extract is broken through, and the CTC and passivation rate are remarkably increased by combining with a natural synergist; the invention further provides a method for preventing and treating plant diseases.

Description

Technical Field

[0001] The present invention relates to the technical field of plant disease prevention and control, in particular to a plant disease prevention and control composition and a plant disease prevention and control method. Background Art

[0002] Fungal damage, also known as fungal diseases, is an infectious disease of plants that can be transmitted to other plants and has an infection process. The pathogens are generally parasitic fungi. There are many types of fungal diseases, accounting for over 70% to 80% of all plant diseases. Fungal diseases are widespread in my country, not only causing damage in the field but also, due to their latent infection, harming fruit, reducing yields and devaluing the fruit. This can lead to significant losses and seriously impact fruit production safety. Fungal damage primarily affects plants, and examples include gray mold, downy mildew, and bacterial wilt.

[0003] Currently, fungal diseases are mostly treated with chemical pesticides. However, long-term use of traditional chemical pesticides has led to increased pathogen resistance, imbalances in the soil microbiome, and pesticide residues. In recent years, botanical pesticides have garnered attention due to their environmental friendliness. However, single plant extracts have limitations such as a narrow control spectrum and a short duration of effectiveness. For example, while sophora alopecuroides alkaloids are effective against some fungi, they lack the ability to inactivate viruses.

[0004] In view of this, the inventors specially designed a composition for preventing and controlling plant diseases and a method for preventing and controlling plant diseases, which resulted in the present case. Summary of the Invention

[0005] The present invention aims to address at least one of the technical problems existing in the prior art. To this end, the present invention provides a plant disease control composition that forms a synergistic antibacterial and antiviral system by combining a specific ratio of total alkaloids from Sophora alopecuroides with high-purity tea tree oil. Combined with a natural synergist, this composition significantly improves CTC and deactivation rates, overcoming the pesticide residue issues associated with existing chemical pesticides.

[0006] The invention also provides a method for preventing and controlling plant diseases.

[0007] The plant disease control composition provided by the present invention comprises the following components: Total alkaloids from Sophora alopecuroides: 8%-25%, wherein the total alkaloids from Sophora alopecuroides include matrine, oxymatrine, and sophocarpine, with a mass ratio of (5-7):(2-3):(1-2); Tea tree oil: 10%-35%; Natural enhancers: 3%-15%; Natural emulsifier: 5%-18%; Food grade solvent: 12%-30%; The balance was deionized water.

[0008] The plant disease control composition of the present invention forms a synergistic antibacterial and antiviral system through a specific ratio of total alkaloids from Sophora alopecuroides and high-purity tea tree oil, so that the composition can synergistically control fungal diseases and viral diseases, breaking through the limitation of the narrow spectrum of action of a single plant extract. At the same time, combined with a natural synergist, it significantly improves the CTC and passivation rate.

[0009] In some embodiments of the present invention, the co-toxicity coefficient (CTC) of the composition against tomato gray mold is ≥150, and the inactivation rate of the composition against tobacco mosaic virus is ≥90%.

[0010] In some embodiments of the present invention, the terpineol content in the tea tree oil is ≥35%, and the eucalyptol content is ≤8%.

[0011] In some embodiments of the present invention, the natural synergist is a compound of wood vinegar and humic acid in a mass ratio of (3-5):1, or an esterification product of rosmarinic acid and L-lactic acid, with an esterification degree of 85% or higher. The wood vinegar-humic acid composite synergist used enhances soil remediation while enhancing pest control efficacy.

[0012] In some embodiments of the present invention, the natural emulsifier is tea saponin, lecithin or a mixture of the two, and the food-grade solvent is ethanol, ethyl oleate or an azeotropic mixture of the two.

[0013] In some embodiments of the present invention, the total alkaloids of Sophora alopecuroides are prepared by the following method: a) performing ultrasonic-assisted extraction on Sophora alopecuroides seeds using a 70%-85% ethanol solution to obtain an extract, with an ultrasonic power of 400-600W, wherein the ratio of Sophora alopecuroides seeds to the ethanol solution is 1:12-1:18; b) the extract was purified by macroporous resin using an ethanol-water solution at pH 4.5 in a volume ratio of 7:3 as eluent; c) collecting the eluate and concentrating it until the alkaloid content is ≥ 60%; Ultrasonic-assisted extraction combined with macroporous resin-directed purification increases the alkaloid yield to twice or more than that of traditional methods.

[0014] In some embodiments of the present invention, the tea tree oil is subjected to molecular distillation and refining treatment, and the specific conditions are: Distillation temperature: 80-95°C; Vacuum degree: 0.1-0.5mbar; Feed rate: 1.5-2.5 mL / min; Molecular distillation refines tea tree oil, doubling the content of the key antibacterial ingredient α-terpineol. The α-terpineol content in the treated tea tree oil is increased to 1.8-2.3 times that of the raw oil.

[0015] In some embodiments of the present invention, the natural synergist is a complex of wood vinegar and humic acid in a mass ratio of (3-5):1, wherein the wood vinegar is prepared by the following process: a) collecting condensate from dry distillation of walnut shells at 450-550° C.; b) using an activated carbon-diatomaceous earth composite column for decoking, wherein the mass ratio of the activated carbon-diatomaceous earth composite column is 1:2; c) adding 0.05%-0.1% of Bacillus natto fermentation broth and aging at 35°C for 72 hours.

[0016] In some embodiments of the present invention, the emulsifier is a mixture of tea saponin and lecithin, with a mass ratio of (2-4):1, wherein: Tea saponin purity ≥90%, foaming ≤15mL / 10min, tested according to GB / T13173 standard; The phosphatidylcholine content in lecithin is ≥70%.

[0017] In some embodiments of the present invention, the plant disease control composition is prepared by the following method: a) dissolving total alkaloids from Sophora alopecuroides in ethyl oleate preheated to 45±2°C, and adding tea tree oil to form an oil phase; b) melt-mixing the tea saponin and wood vinegar complex at 60° C. and slowly adding the mixture to the oil phase while maintaining a shear rate of 8000-12000 rpm; c) When the temperature drops below 30°C, add humic acid stabilizer and continue shear emulsification for 10-15 minutes; d) Homogenize to a particle size of D90 ≤ 200 nm and fill with nitrogen for protection before filling.

[0018] The plant disease prevention and control method provided by the present invention comprises: a) Preventive application: spray the leaves with 800-1000 times dilution at a rate of 200-300 L / ha during the budding stage of crops; b) Therapeutic application: At the initial stage of the disease, spray the leaves with a 300-500 times diluted solution and irrigate the roots with a 200 times diluted solution, with a root irrigation volume of 5-8L / plant.

[0019] In some embodiments of the present invention, the diseases include but are not limited to gray mold, downy mildew, and bacterial wilt.

[0020] In some embodiments of the present invention, the root irrigation solution is enhanced by: a) mixing the pest control composition and biochar in a mass ratio of 1:0.5; b) Add 0.1%~0.3% of Trichoderma harzianum spore powder (viable spore count ≥2×10^8 CFU / g); c) solid-state fermentation at 35°C for 48 hours to ensure a spore germination rate of ≥95%.

[0021] In some embodiments of the present invention, the half-life of the preparation in the soil is ≤7 days, and after continuous application for three seasons, the soil microbial diversity index is increased by 0.8-1.2 compared with the chemical agent treatment group, which is significantly better than the chemical agent. DETAILED DESCRIPTION

[0022] The technical solution of the present invention is further described below with reference to the examples. Where specific techniques or conditions are not specified in the examples, the techniques or conditions described in the literature in the art or in the product instructions were used. Where the manufacturer of the reagents or instruments used is not specified, they are all commercially available conventional products.

[0023] The present invention provides a composition for preventing and controlling plant diseases, comprising the following components: Total alkaloids from Sophora alopecuroides: 8%-25%, wherein the total alkaloids from Sophora alopecuroides include matrine, oxymatrine, and sophocarpine, with a mass ratio of (5-7):(2-3):(1-2); Tea tree oil: 10%-35%, of which the terpineol content in tea tree oil is ≥35% and the eucalyptol content is ≤8%; Natural synergist: 3%-15%. This natural synergist is a compound of wood vinegar and humic acid in a mass ratio of (3-5):1, or an esterification product of rosmarinic acid and L-lactic acid with an esterification degree of 85% or higher. This wood vinegar-humic acid composite synergist enhances both pest control and soil remediation. Natural emulsifier: 5%-18%, the natural emulsifier is tea saponin, lecithin or a mixture of the two, and the food-grade solvent is ethanol, ethyl oleate or an azeotropic mixture of the two; Food grade solvent: 12%-30%; The balance was deionized water.

[0024] The plant disease control composition of this invention utilizes a specific ratio of total alkaloids from Sophora alopecuroides and high-purity tea tree oil to form a synergistic antibacterial and antiviral system. This system achieves synergistic control of fungal and viral diseases, overcoming the narrow spectrum of action of a single plant extract. Furthermore, the combination of a natural synergist significantly enhances the CTC and inactivation rate. The composition exhibits a co-toxicity coefficient (CTC) of ≥150 against Botrytis cinerea and a ≥90% inactivation rate against tobacco mosaic virus.

[0025] The total alkaloids of Sophora alopecuroides in the present invention are prepared by the following method: a) performing ultrasonic-assisted extraction on Sophora alopecuroides seeds using a 70%-85% ethanol solution to obtain an extract, with an ultrasonic power of 400-600W, wherein the ratio of Sophora alopecuroides seeds to the ethanol solution is 1:12-1:18; b) the extract was purified by macroporous resin AB-8 using an ethanol-water solution at pH 4.5 in a volume ratio of 7:3 as the eluent; c) collecting the eluate and concentrating it until the alkaloid content is ≥ 60%; Ultrasonic-assisted extraction combined with macroporous resin-directed purification increases the alkaloid yield to twice or more than that of traditional methods.

[0026] The tea tree oil of the present invention is subjected to molecular distillation and refining treatment, and the specific conditions are: Distillation temperature: 80-95°C; Vacuum degree: 0.1-0.5mbar; Feed rate: 1.5-2.5 mL / min; Molecular distillation refines tea tree oil, doubling the content of the key antibacterial ingredient α-terpineol. The α-terpineol content in the treated tea tree oil is increased to 1.8-2.3 times that of the raw oil.

[0027] The natural synergist described in the present invention is a compound composed of wood vinegar and humic acid in a mass ratio of (3-5):1, wherein the wood vinegar is prepared by the following process: a) collecting condensate from dry distillation of walnut shells at 450-550° C.; b) using an activated carbon-diatomaceous earth composite column for decoking, wherein the mass ratio of the activated carbon-diatomaceous earth composite column is 1:2; c) adding 0.05%-0.1% of Bacillus natto fermentation broth and aging at 35°C for 72 hours.

[0028] The emulsifier is a mixture of tea saponin and lecithin, the mass ratio of the two is (2-4):1, wherein: Tea saponin purity ≥90%, foaming ≤15mL / 10min, tested according to GB / T13173 standard; The phosphatidylcholine content in lecithin is ≥70%.

[0029] The plant disease control composition is prepared by the following method: a) dissolving total alkaloids from Sophora alopecuroides in ethyl oleate preheated to 45±2°C, and adding tea tree oil to form an oil phase; b) melt-mixing the tea saponin and wood vinegar complex at 60° C. and slowly adding the mixture to the oil phase while maintaining a shear rate of 8000-12000 rpm; c) When the temperature drops below 30°C, add humic acid stabilizer and continue shear emulsification for 10-15 minutes; d) Homogenize to a particle size of D90 ≤ 200 nm and fill with nitrogen for protection before filling.

[0030] The plant disease prevention and control method provided by the present invention comprises: a) Preventive application: spray the leaves with 800-1000 times dilution at a rate of 200-300 L / ha during the budding stage of crops; b) Therapeutic application: At the initial stage of the disease, spray the leaves with a 300-500 times diluted solution and irrigate the roots with a 200 times diluted solution, with a root irrigation volume of 5-8L / plant.

[0031] The diseases include but are not limited to gray mold, downy mildew and bacterial wilt.

[0032] The root irrigation solution is enhanced by the following methods: a) mixing the pest control composition and biochar in a mass ratio of 1:0.5; b) Add 0.1%~0.3% of Trichoderma harzianum spore powder (viable spore count ≥2×10^8 CFU / g); c) solid-state fermentation at 35°C for 48 hours to ensure a spore germination rate of ≥95%.

[0033] The half-life of the preparation in the soil is ≤7 days, and after continuous application for three seasons, the soil microbial diversity index is increased by 0.8~1.2 compared with the chemical agent treatment group, which is significantly better than the chemical agent.

[0034] The following is further described by specific examples: Examples 1-5 (see Table 1)

[0035] Experimental data (Examples 1-5, see Table 2)

[0036] Among them, the following determination methods are used: CTC determination: Refer to NY / T 1156-2006 and use the Sun Yunpei method to calculate the co-toxicity coefficient.

[0037] Virus inactivation rate: The composition was mixed with the virus suspension at a ratio of 1:10, and the mixture was inoculated on tobacco leaves 48 hours later. The lesion inhibition rate was calculated.

[0038] Soil half-life: The degradation kinetics curve was detected by HPLC.

[0039] Microbial diversity: Shannon index was calculated based on 16S rRNA sequencing and compared with the chemical treatment group.

[0040] Example 6, Preparation of Synergistic Root Irrigation Solution The composition of Example 2 was mixed with biochar (1:0.5), and 0.2% Trichoderma harzianum spore powder (2 × 10^8 CFU / g) was added. Solid-state fermentation was carried out at 35°C for 48 hours, resulting in a spore germination rate of 96%. When used for root irrigation, a 200-fold dilution achieved an 88% efficacy against bacterial wilt.

[0041] Example 7, Molecular Distillation Refined Tea Tree Oil The α-terpineol content in the raw tea tree oil was 8%, which was increased to 18.4% after molecular distillation at 90°C and 0.3 mbar (data from Example 2), and the CTC was increased from 142 to 168.

[0042] Example 8, Comparative Example Control group 1 (matrine 15% only): CTC = 102, passivation rate = 72%; Control group 2 (matrine + tea tree oil, no enhancer): CTC = 128, passivation rate = 85%.

[0043] In summary, the plant disease control composition of the present invention forms a synergistic antibacterial and antiviral system through a specific ratio of total alkaloids from Sophora alopecuroides and high-purity tea tree oil, so that the composition can synergistically control fungal diseases and viral diseases, breaking through the limitation of the narrow spectrum of action of a single plant extract. At the same time, combined with natural synergists, it significantly improves CTC and passivation.

[0044] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and purpose of the present invention.

Claims

1. A composition for preventing and controlling plant diseases, characterized in that: Includes the following ingredients: Total alkaloids from Sophora alopecuroides: 8%-25%, wherein the total alkaloids from Sophora alopecuroides include matrine, oxymatrine, and sophocarpine, with a mass ratio of (5-7):(2-3):(1-2); Tea tree oil: 10%-35%; Natural enhancers: 3%-15%; Natural emulsifier: 5%-18%; Food grade solvent: 12%-30%; The balance was deionized water.

2. The plant disease control composition according to claim 1, characterized in that The terpineol content in the tea tree oil is ≥35%, and the eucalyptol content is ≤8%.

3. The plant disease control composition according to claim 1, characterized in that The natural synergist is a compound of wood vinegar and humic acid in a mass ratio of (3-5):1, or an esterification product of rosmarinic acid and L-lactic acid, and the esterification degree is ≥85%.

4. The plant disease control composition according to claim 1, characterized in that The natural emulsifier is tea saponin, lecithin or a mixture of the two, and the food-grade solvent is ethanol, ethyl oleate or an azeotropic mixture of the two.

5. The plant disease control composition according to claim 1, characterized in that The sophora alopecuroides total alkaloids are prepared by the following method: a) performing ultrasonic-assisted extraction on Sophora alopecuroides seeds using a 70%-85% ethanol solution to obtain an extract, with an ultrasonic power of 400-600W, wherein the ratio of Sophora alopecuroides seeds to the ethanol solution is 1:12-1:18; b) the extract was purified by macroporous resin using an ethanol-water solution at pH 4.5 in a volume ratio of 7:3 as eluent; c) Collect the eluate and concentrate it until the alkaloid content is ≥60%.

6. The plant disease control composition according to claim 1, characterized in that The tea tree oil is subjected to molecular distillation and refining treatment, and the specific conditions are: Distillation temperature: 80-95°C; Vacuum degree: 0.1-0.5mbar; Feed rate: 1.5-2.5 mL / min.

7. The plant disease control composition according to claim 1, characterized in that The natural synergist is a compound of wood vinegar and humic acid in a mass ratio of (3-5):1, wherein the wood vinegar is prepared by the following process: a) collecting condensate from dry distillation of walnut shells at 450-550° C.; b) using an activated carbon-diatomaceous earth composite column for decoking, wherein the mass ratio of the activated carbon-diatomaceous earth composite column is 1:2; c) adding 0.05%-0.1% of Bacillus natto fermentation broth and aging at 35°C for 72 hours.

8. The plant disease control composition according to claim 1, characterized in that The emulsifier is a mixture of tea saponin and lecithin, the mass ratio of the two is (2-4):1, wherein: Tea saponin purity ≥90%, foaming ≤15mL / 10min; The phosphatidylcholine content in lecithin is ≥70%.

9. The plant disease control composition according to claim 1, characterized in that The plant disease control composition is prepared by the following method: a) dissolving total alkaloids from Sophora alopecuroides in ethyl oleate preheated to 45±2°C, and adding tea tree oil to form an oil phase; b) melt-mixing the tea saponin and wood vinegar complex at 60° C. and slowly adding the mixture to the oil phase while maintaining a shear rate of 8000-12000 rpm; c) When the temperature drops below 30°C, add humic acid stabilizer and continue shear emulsification for 10-15 minutes; d) Homogenize to a particle size of D90 ≤ 200 nm and fill with nitrogen for protection before filling.

10. A method for preventing and controlling plant diseases, characterized in that: include: a) Preventive application: spray the leaves with 800-1000 times dilution at a rate of 200-300 L / ha during the budding stage of crops; b) Therapeutic application: At the initial stage of the disease, spray the leaves with a 300-500 times diluted solution and irrigate the roots with a 200 times diluted solution, with a root irrigation volume of 5-8L / plant.

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