Natural plant source composite slow-release emulsion herbicide

Abstract

The application discloses a natural plant source composite sustained-release emulsion herbicide. Active ingredients of the herbicide are turpentine, capric acid and nonanoic acid. The active ingredients of the preparation, the capric acid, the nonanoic acid and the turpentine, have a synergistic effect, compared with single active core materials, the use of the active ingredients can be reduced under the condition of ensuring the same efficacy, the production cost is reduced, and the potential environmental burden is reduced. The wall material, corn starch, used in the preparation is non-toxic and harmless, and is easy to degrade in the natural environment, and the degradation products are non-toxic and harmless to human beings. Different kinds of auxiliaries such as emulsifiers, wall materials and solvents are screened, so that the herbicide of the application has the optimal efficacy and sustained-release effect.

Description

Technical Field

[0001] This invention belongs to the field of pesticide technology, specifically relating to a natural plant-derived slow-release compound synergistic emulsion herbicide. Background Technology

[0002] Weeds are one of the main causes of crop yield reduction. Currently, the primary means of weed control is through chemical pesticides. However, over time, the shortcomings of traditional chemical herbicides have become increasingly apparent, and the extensive use of chemical herbicides in the field has led to the gradual development of herbicide resistance in weeds. Therefore, the development of natural plant-derived, compound, slow-release herbicides is of great significance.

[0003] Slow-release herbicides allow for the slow release of pesticides over a specific period, prolonging their efficacy, reducing losses, and also decreasing their toxicity, pesticide dosage, and pollution. Slow-release pesticide formulations can be broadly classified into physical and chemical slow-release formulations. Chemical slow-release formulations are made by chemically binding the active groups of the pesticide to a carrier, while physical slow-release formulations are made by physically mixing pesticides with polymers, including microcapsules, emulsions, and slow-release films. Emulsions mainly consist of four parts: the active ingredient, solvent, emulsifier, and water. In this system, the oil and water phases are separated by an interface formed by surfactants. With the help of functional adjuvants, emulsions solubilize water-insoluble pesticides in water to form an emulsion-like liquid formulation, which can improve pesticide performance, increase pesticide utilization, and enhance pesticide adhesion to the target surface, resulting in better slow-release effects.

[0004] Caprylic acid, also known as caprylic acid, has the chemical formula C8H. 16O2, a natural product, is found in apples, coconut oil, nutmeg, wine, etc. It can be obtained by saponifying coconut oil, followed by acidification and fractionation. It is mainly used in the production of dyes, pharmaceuticals, and fragrances. Nonanoic acid is widely found in plants and belongs to fatty acids or carboxylic acid compounds. It mostly exists in the form of esters in essential oils, with very few existing in free form. It is a contact herbicide, broad-spectrum, non-selective, and can control annual and perennial broadleaf weeds and some grass weeds. Turpentine oil mainly consists of α-pinene and β-pinene. It is a volatile oil obtained by distillation or extraction of oleoresin exuded from plants. It can be used as a precursor for the synthesis of compounds with strong herbicidal activity, such as epoxy-containing monoterpene esters and ethers. Current reports confirm that caprylic acid and nonanoic acid are environmentally friendly natural herbicidal active substances, and turpentine is a potential natural plant-derived herbicidal active substance. Existing technologies have also reported many other natural herbicidal active substances. Compared with the active ingredients of traditional chemical herbicides, the above-mentioned components have advantages such as low toxicity, broad spectrum, and easy degradation. Although these substances all have certain activity, the activity is generally not high. When active components are combined, the biological activity is often even lower, far from achieving the effect of chemical pesticides. Finding natural herbicidal active substance complexes that can achieve or approach the effect of chemical pesticides is a worthy research topic. Summary of the Invention

[0005] The purpose of this invention is to provide a natural plant-derived compound slow-release emulsion herbicide.

[0006] A natural plant-derived compound slow-release emulsion herbicide, wherein the active ingredients of the herbicide are turpentine oil, caprylic acid, and nonanoic acid.

[0007] It comprises the following components by weight percentage: turpentine 8%-14%, caprylic acid 2%-6%, nonanoic acid 2%-8%, emulsion stabilizer 3%-7%, antifreeze 0.1%-1%, wall material 21%-41%, solvent 20%-30%, and the balance being water.

[0008] The emulsifying stabilizer is Tween-80 and / or Tween-40.

[0009] The antifreeze is one or more of ethylene glycol, methanol, ethanol, isopropanol, propylene glycol, diethylene glycol, ethylene glycol butyl ether, propylene glycol butyl ether, ethylene glycol butyl ether acetate, dichloromethane, dimethyl sulfoxide, formamide, calcium chloride, sodium acetate, and magnesium chloride.

[0010] The wall material is one or more of corn starch, β-cyclodextrin, and maltodextrin.

[0011] The solvent is one or more of sodium hydroxide solution, potassium hydroxide solution, and potassium carbonate solution; the mass fraction of the solute in the solvent is 0.05% to 0.1%.

[0012] The preparation method of the natural plant-derived compound slow-release emulsion herbicide is carried out according to the following steps:

[0013] (1) Dissolve the wall material in a solvent and stir magnetically for 10-30 min to obtain solution A;

[0014] (2) Take turpentine oil, caprylic acid and nonanoic acid, and mix them to obtain solution B;

[0015] (3) Mix solutions A and B with emulsifying stabilizer and antifreeze to obtain solution C;

[0016] (4) After dispersing solution C using a high-speed disperser at a speed of 13,000-17,000 rpm, transfer it to a high-pressure homogenizer for homogenization to obtain a stable and uniform emulsion herbicide.

[0017] The high-pressure homogenization parameters are 300 MPa-400 MPa for primary homogenization and 100 MPa-150 MPa for secondary homogenization.

[0018] The application of the natural plant-derived compound slow-release emulsion herbicide in weed control.

[0019] The weeds include: watercress, bird's tongue grass, fish-eye grass, knotweed, coriander, cleavers, cudweed, geranium, buttercup, shepherd's purse, mudwort, chickweed; goosegrass, dayflower, crabgrass, euryale ferox, horse pine, purslane, wolfberry, beggar-ticks, angelica sinensis, grass dragon, cocklebur, white flower snake tongue grass; perilla, achyranthes bidentata, purslane, spiny amaranth, plantain, sisal sieve, moonflower, lotus seed grass; fleabane, revolutionary vegetable, hop, sorrel, shepherd's purse; foxtail grass, privet grass.

[0020] The beneficial effects of this invention are as follows: The active ingredients caprylic acid, nonanoic acid, and turpentine in the formulation of this invention have a synergistic effect. Compared with a single active core material, it can reduce the amount of each ingredient used while ensuring the same efficacy, thereby reducing production costs and potential environmental burden. The corn starch used as the wall material in the formulation of this invention is non-toxic and harmless, easily degrades in the natural environment, and its degradation products are non-toxic and harmless to humans. This invention has screened different types of adjuvants such as emulsifiers, wall materials, and solvents, thereby enabling the herbicide of this invention to achieve optimal efficacy and sustained-release effect. Detailed Implementation

[0021] To facilitate understanding of the present invention, a more comprehensive description will be provided below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the present invention.

[0022] Example 1

[0023] Soil samples were collected in Tianjin. Topsoil was sieved through a 2mm sieve and then mixed thoroughly before use. Analysis showed a soil moisture content of 25.4%, pH 6.6, soil organic matter content of 6.8%, and NH4+ content of [missing information]. 4+ -N 19.2mg / kg, NO 3- -N 121.5mg / kg, available phosphorus 566.6mg / kg, available potassium 665.8mg / kg.

[0024] Turpentine, caprylic acid, and nonanoic acid were dissolved in hexane. A 10% (w / w) solution of turpentine, a 4% (w / w) solution of caprylic acid, and a 4% (w / w) solution of nonanoic acid were prepared. 1000g of prepared soil sample was weighed and placed in a container (10cm thick). Forty pre-germinated seeds of purslane, wild lettuce, crabgrass, plantain, and foxtail grass were sown on the soil surface. 30g of turpentine solution and 30g of caprylic acid solution were accurately weighed. Acid solution and 30g nonanoic acid solution were transferred to a small sprayer. When using various solutions in pairs, 30g of each solution was used. When using turpentine solution, caprylic acid solution and nonanoic acid solution in combination, 30g of each solution was used. The solution was sprayed at 25℃ and then the air was closed for 1 day. After the air closure ended, the air was opened for 5 days. Then the shoot length of purslane, wild lettuce, crabgrass, plantain and foxtail grass was measured. The control was sprayed with n-hexane alone and then the air was closed for 1 day. After the air closure ended, the air was opened for 5 days. Each treatment was repeated 5 times.

[0025] The weed control efficacy is calculated using the following formula:

[0026]

[0027] The efficacy of the mixture was calculated using the Colby method (1966) and compared with the measured efficacy, providing a simple and effective way to evaluate the combined effect of the mixture. The calculation formula is as follows:

[0028]

[0029] E represents the theoretical efficacy of the mixture; n represents the quantity of the mixed agents; X1 represents the efficacy after applying the first agent; X2 represents the efficacy after applying the second agent; X n This indicates the efficacy after applying the nth agent. When the actual efficacy of the mixture is greater than the theoretical efficacy, it indicates synergistic effect; when the actual efficacy is less than the theoretical efficacy, it indicates antagonistic effect.

[0030] Table 1. Effects of a mixture of turpentine, caprylic acid, and nonanoic acid on purslane.

[0031]

[0032] As can be seen from Table 1, compared with single agents, the combination of turpentine oil, caprylic acid and nonanoic acid, as well as the combination of all of them, showed a synergistic effect on the control of purslane.

[0033] Table 2. Effects of a mixture of turpentine oil, caprylic acid, and nonanoic acid on *Sonchus oleraceus*.

[0034]

[0035]

[0036] As can be seen from Table 2, compared with single agents, the combination of turpentine oil, caprylic acid and nonanoic acid, as well as the combination of all of them, showed a synergistic effect on the control of Sophora flavescens.

[0037] Table 3. Effects of a mixture of turpentine, caprylic acid, and nonanoic acid on crabgrass.

[0038]

[0039] As can be seen from Table 3, compared with single agents, the combination of turpentine oil, caprylic acid and nonanoic acid, as well as the combination of all of them, showed a synergistic effect on the control of crabgrass.

[0040] Table 4. Effects of a mixture of turpentine, caprylic acid, and nonanoic acid on plantain.

[0041]

[0042]

[0043] As can be seen from Table 4, compared with single agents, the combination of turpentine oil, caprylic acid and nonanoic acid, as well as the combination of all of them, showed a synergistic effect on the control of plantain.

[0044] Table 5. Effects of a mixture of turpentine, caprylic acid, and nonanoic acid on foxtail grass.

[0045]

[0046] As can be seen from Table 5, compared with single agents, the combination of turpentine oil, caprylic acid and nonanoic acid, as well as the combination of all of them, showed a synergistic effect on the control of foxtail grass.

[0047] Example 2

[0048] A natural plant-derived compound slow-release emulsion herbicide comprises the following components by weight percentage: 10% turpentine oil, 4% caprylic acid, 4% nonanoic acid, 5% Tween-80, 0.5% ethylene glycol, 30% corn starch, 25% sodium hydroxide solution with a mass fraction of 0.08%, and the balance being water.

[0049] The preparation method of the natural plant-derived compound slow-release emulsion herbicide is carried out according to the following steps:

[0050] (1) Dissolve corn starch in a 0.08% sodium hydroxide solution and stir magnetically for 20 min to obtain solution A;

[0051] (2) Take turpentine oil, caprylic acid and nonanoic acid, and mix them to obtain solution B;

[0052] (3) Mix solutions A and B with Tween-80 and ethylene glycol to obtain solution C;

[0053] (4) After dispersing solution C using a high-speed disperser at a speed of 15000 rpm, it is transferred to a high-pressure homogenizer for homogenization to obtain a stable and uniform emulsion herbicide; the high-pressure homogenization parameters are 350 MPa for primary homogenization and 120 MPa for secondary homogenization.

[0054] Example 3

[0055] A natural plant-derived compound slow-release emulsion herbicide comprises the following components by weight percentage: 12% turpentine oil, 5% caprylic acid, 6% nonanoic acid, 5% Tween-40, 0.8% propylene glycol, 36% β-cyclodextrin, 28% potassium hydroxide solution with a mass fraction of 0.07%, and the balance being water.

[0056] The preparation method of the natural plant-derived compound slow-release emulsion herbicide is carried out according to the following steps:

[0057] (1) Dissolve β-cyclodextrin in a 0.07% potassium hydroxide solution and stir magnetically for 15 min to obtain solution A;

[0058] (2) Take turpentine oil, caprylic acid and nonanoic acid, and mix them to obtain solution B;

[0059] (3) Mix solution A, solution B with emulsified Tween-40 and propylene glycol to obtain solution C;

[0060] (4) After dispersing solution C using a high-speed disperser at a speed of 14,000 rpm, it is transferred to a high-pressure homogenizer for homogenization to obtain a stable and uniform emulsion herbicide; the high-pressure homogenization parameters are 320 MPa for primary homogenization and 100 MPa for secondary homogenization.

[0061] Example 4

[0062] A natural plant-derived compound slow-release emulsion herbicide comprises the following components by weight percentage: 13% turpentine oil, 6% caprylic acid, 8% nonanoic acid, 7% Tween-80, 1% ethylene glycol butyl ether acetate, 40% maltodextrin, 30% potassium carbonate solution with a mass fraction of 0.05%, and the balance being water.

[0063] The preparation method of the natural plant-derived compound slow-release emulsion herbicide is carried out according to the following steps:

[0064] (1) Dissolve maltodextrin in a 0.05% potassium carbonate solution and stir magnetically for 30 min to obtain solution A;

[0065] (2) Take turpentine oil, caprylic acid and nonanoic acid, and mix them to obtain solution B;

[0066] (3) Mix solutions A and B with Tween-80 and ethylene glycol butyl ether acetate to obtain solution C;

[0067] (4) After dispersing solution C using a high-speed disperser at a speed of 17,000 rpm, it is transferred to a high-pressure homogenizer for homogenization to obtain a stable and uniform emulsion herbicide; the high-pressure homogenization parameters are 400 MPa for primary homogenization and 150 MPa for secondary homogenization.

[0068] Example 5

[0069] A natural plant-derived compound slow-release emulsion herbicide comprises the following components by weight percentage: 8% turpentine oil, 2% caprylic acid, 2% nonanoic acid, 3% Tween-80, 0.1% sodium acetate, 21% corn starch, 20% sodium hydroxide solution with a mass fraction of 0.05%, and the balance being water.

[0070] The preparation method of the natural plant-derived compound slow-release emulsion herbicide is carried out according to the following steps:

[0071] (1) Dissolve corn starch in a 0.05% sodium hydroxide solution and stir magnetically for 10 min to obtain solution A;

[0072] (2) Take turpentine oil, caprylic acid and nonanoic acid, and mix them to obtain solution B;

[0073] (3) Mix solutions A and B with Tween-80 and sodium acetate to obtain solution C;

[0074] (4) After dispersing solution C using a high-speed disperser at a speed of 13000 rpm, it is transferred to a high-pressure homogenizer for homogenization to obtain a stable and uniform emulsion herbicide; the high-pressure homogenization parameters are 400 MPa for primary homogenization and 150 MPa for secondary homogenization.

[0075] Example 6

[0076] A natural plant-derived compound slow-release emulsion herbicide comprises the following components by weight percentage: 12% turpentine oil, 3% caprylic acid, 3% nonanoic acid, 4% Tween-40, 0.2% propylene glycol butyl ether, 25% β-cyclodextrin, 22% potassium hydroxide solution with a mass fraction of 0.06%, and the balance being water.

[0077] The preparation method of the natural plant-derived compound slow-release emulsion herbicide is carried out according to the following steps:

[0078] (1) Dissolve β-cyclodextrin in a 0.06% potassium hydroxide solution and stir magnetically for 10-30 min to obtain solution A;

[0079] (2) Take turpentine oil, caprylic acid and nonanoic acid, and mix them to obtain solution B;

[0080] (3) Mix solutions A and B with Tween-40 and propylene glycol butyl ether to obtain solution C;

[0081] (4) After dispersing solution C using a high-speed disperser at a speed of 15000 rpm, transfer it to a high-pressure homogenizer for homogenization to obtain a stable and uniform emulsion herbicide; the high-pressure homogenization parameters are 300 MPa-400 MPa for primary homogenization and 100 MPa-150 MPa for secondary homogenization.

[0082] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A natural plant-derived compound slow-release emulsion herbicide, characterized in that, It includes the following components by weight percentage: turpentine 8%-14%, caprylic acid 2%-6%, nonanoic acid 2%-8%, emulsifying stabilizer 3%-7%, antifreeze 0.1%-1%, wall material 21%-41%, solvent 20%-30%, and the balance being water.

2. The natural plant-derived compound slow-release emulsion herbicide according to claim 1, characterized in that, The emulsifying stabilizer is Tween-80 and / or Tween-40.

3. The natural plant-derived compound slow-release emulsion herbicide according to claim 1, characterized in that, The antifreeze is one or more of ethylene glycol, methanol, ethanol, isopropanol, propylene glycol, diethylene glycol, ethylene glycol butyl ether, propylene glycol butyl ether, ethylene glycol butyl ether acetate, dichloromethane, dimethyl sulfoxide, formamide, calcium chloride, sodium acetate, and magnesium chloride.

4. The natural plant-derived compound slow-release emulsion herbicide according to claim 1, characterized in that, The wall material is one or more of corn starch, β-cyclodextrin, and maltodextrin.

5. The natural plant-derived compound slow-release emulsion herbicide according to claim 1, characterized in that, The solvent is one or more of sodium hydroxide solution, potassium hydroxide solution, and potassium carbonate solution; the mass fraction of the solute in the solvent is 0.05% to 0.1%.

6. The method for preparing the natural plant-derived compound slow-release emulsion herbicide according to claim 1, characterized in that, Follow these steps: (1) Dissolve the wall material in the solvent and stir magnetically for 10-30 min to obtain solution A; (2) Take turpentine, caprylic acid and nonanoic acid, and mix them to obtain solution B; (3) Mix solution A and solution B with emulsifying stabilizer and antifreeze to obtain solution C; (4) After dispersing solution C using a high-speed disperser at a speed of 13,000-17,000 rpm, transfer it to a high-pressure homogenizer for homogenization to obtain a stable and uniform emulsion herbicide.

7. The method for preparing the natural plant-derived compound slow-release emulsion herbicide according to claim 6, characterized in that, The high-pressure homogenization parameters are 300 MPa-400 MPa for primary homogenization and 100 MPa-150 MPa for secondary homogenization.

8. The application of the natural plant-derived compound slow-release emulsion herbicide of claim 1 in the control of weeds.

9. The application of the natural plant-derived compound slow-release emulsion herbicide according to claim 8 in weed control, characterized in that, The weeds selected are: watercress, bird's tongue grass, fish-eye grass, knotweed, coriander, cleavers, cudweed, geranium, buttercup, shepherd's purse, mudwort, chickweed; goosegrass, dayflower, crabgrass, euryale ferox, horse pine, purslane, wolfberry, beggar-ticks, angelica sinensis, grass dragon, cocklebur, white flower snake tongue grass; perilla, achyranthes bidentata, purslane, spiny amaranth, plantain, sisal sieve, moonflower, lotus seed grass; fleabane, revolutionary vegetable, hop, sorrel, shepherd's purse; foxtail grass, licorice.

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