Efficient herbicide composition and preparation method thereof

Abstract

The invention belongs to the technical field of agricultural herbicides, and particularly relates to a high-efficiency herbicide composition and a preparation method thereof. The herbicide composition comprises an active component A and a carrier component B, the active ingredient A is prepared from the following components in parts by weight: 25 to 35 parts of prometryn, 30 to 40 parts of simetryn, 5 to 10 parts of pretilachlor, 5 to 8 parts of thisulfuron-methyl, 6 to 10 parts of florasulam, 3 to 5 parts of plant extract and 1 to 2 parts of synergistic additive; the carrier component B is prepared from the following components in parts by weight: 3 to 5 parts of chitosan-PLA compound, 1 to 2 parts of modified silicon dioxide, 2 to 3 parts of polyethylene wax and 0.3 to 0.5 part of beta-cyclodextrin. By reasonably proportioning triazines and sulfonylureas for weeding, different action mechanisms are covered, the weeding effect is enhanced, the resistance risk is reduced, the permeability and absorption efficiency are improved by adding the natural plant extract and the synergistic additive, and the slow-release, efficient and environment-friendly effects are achieved by matching with the composite carrier.

Description

Technical Field

[0001] The present invention belongs to the technical field of agricultural herbicides, and particularly relates to a high-efficiency herbicide composition and a preparation method thereof. Background Art

[0002] With the growth of the global population and the concern for food security, agricultural production efficiency has become particularly important. Weeds are one of the important factors affecting crop yields, so herbicides are widely used in modern agriculture. There are a wide variety of herbicides on the market, including selective herbicides (only targeting certain specific types of weeds) and non-selective herbicides (which can kill almost all plants), and they are classified into contact type, systemic conduction type, etc. according to their action mechanisms. Various herbicides are widely used in existing agricultural production. These herbicides can inhibit or kill weeds to a certain extent. However, they have many defects that affect the weeding effect. For example, the action spectrum of some herbicides is relatively narrow and can only be effective against specific types of weeds. It is difficult to achieve comprehensive weeding in farmland environments where multiple weeds grow mixed. Moreover, with the continuous enhancement of weed resistance, the weeding effect of traditional herbicides gradually decreases, and the dose needs to be continuously increased to achieve a certain weeding purpose. However, increasing the dose will bring problems such as environmental pollution and soil residues, and pose potential hazards to subsequent crops. In addition, under harsh environmental conditions, such as high temperature, high humidity or drought, the herbicidal activity of some herbicides is unstable, resulting in a significant reduction in the weeding effect, and it cannot stably maintain a low level of farmland weeds, affecting the overall growth environment optimization during the growth cycle of crops, and unable to efficiently create a growth condition with no or minimal weed interference for crops, thereby restricting the further improvement of agricultural production efficiency. Long-term use of the same type or the same herbicide is likely to cause weeds to develop resistance, and it will also make the effect of the herbicide gradually weaken. Therefore, based on the above problems, it is extremely necessary to develop a herbicide with high weeding efficiency and low pollution. Summary of the Invention

[0003] Aiming at the defects of the prior art, the purpose of the present invention is to provide a high-efficiency herbicide composition and a preparation method thereof.

[0004] The technical effects of the present invention are achieved through the following technical solutions: A high-efficiency herbicide composition, the composition of which includes an active ingredient A and a carrier ingredient B; the composition of the active ingredient A includes the following components: 25 - 35 parts of prometryn, 30 - 40 parts of simetryn, 5 - 10 parts of pretilachlor, 5 - 8 parts of thifensulfuron-methyl, 6 - 10 parts of florasulam, 3 - 5 parts of plant extracts, and 1 - 2 parts of synergistic adjuvants; the composition of the carrier ingredient B includes the following components: 3 - 5 parts of chitosan-PLA composite, 1 - 2 parts of modified silica, 2 - 3 parts of polyethylene wax, 0.3 - 0.5 parts of β-cyclodextrin.

[0005] Preferably, the plant extract is prepared from clove oil, eucalyptus oil and menthol in a ratio of 0.25:0.3:0.45.

[0006] Preferably, the synergistic auxiliary agent is composed of 0.3 - 0.6 parts of penetrant, 0.3 - 0.5 parts of surfactant and 0.4 - 0.9 parts of chelating agent; the penetrant is dimethyl sulfoxide; the surfactant is any one of Tween - 80, Span - 80 and glycerol ester; the chelating agent is citric acid.

[0007] Preferably, the specific preparation steps of the chitosan - PLA composite are as follows: A1: Add chitosan and Tween - 80 into a 1wt% acetic acid solution, heat to 50 - 60 °C, stir and dissolve evenly to obtain a chitosan solution; add polylactic acid into dichloromethane, stir and dissolve evenly to obtain a polylactic acid solution; A2: Add the polylactic acid solution prepared in step A1 into the chitosan solution, stir at a speed of 1000 - 2000 rpm for 30 min, then add glutaraldehyde and continue to stir for 1 h to obtain a mixed emulsion; add the mixed emulsion into cold water, continuously stir for 1 - 2 h, centrifuge, filter, wash with absolute ethanol, and dry at 70 °C for 6 h to obtain the chitosan - PLA composite; Preferably, in step A1, the dosage ratio of chitosan, Tween - 80 and acetic acid solution is 1 g:0.1 - 0.2 g:50 - 100 mL; the dosage ratio of polylactic acid and dichloromethane is 1 g:30 mL; Preferably, in step A2, the dosage ratio of the polylactic acid solution, chitosan solution, glutaraldehyde and cold water is 1:1:0.005 - 0.006:2 - 3.

[0008] Preferably, the specific preparation steps of the modified silica are as follows: B1: Add silica into absolute ethanol, ultrasonically clean for 30 min, filter, dehydrate with anhydrous sodium sulfate for 1 h, and dry at 60 °C for 6 h to obtain pretreated silica; mix octyltriethoxysilane, absolute ethanol and anhydrous toluene, and stir and mix evenly to obtain a mixed solution; B2: Heat the mixed solution prepared in step B1 to 50 - 60 °C, then slowly add the pretreated silica powder prepared in step B1, continuously stir for 2 - 4 h, centrifuge, filter, repeat washing with absolute ethanol 3 times, and dry at 50 - 60 °C for 4 - 6 h to obtain modified silica; Preferably, in step B1, the dosage ratio of silica and absolute ethanol is 1 g:4 - 5 mL; Preferably, in step B2, the dosage ratio of octyltriethoxysilane, absolute ethanol, anhydrous toluene and pretreated silica is 0.1 - 0.15 mL: 0.5 - 1 mL: 0.5 - 1 mL: 1 g.

[0009] Preferably, on the other hand, the present invention provides a preparation method of an efficient herbicide composition, and the specific preparation steps are as follows: S1: Weigh prometryn, simetryn, pretilachlor, thifensulfuron-methyl and florasulam in proportion and add them into an ethanol solution. Stir at a speed of 300 - 500 rpm for 30 - 60 min, then add a plant extract, continue to stir for 10 - 20 min, and then slowly add a synergistic adjuvant and continue to stir for 20 - 30 min to obtain a mixed active solution; S2: Add the chitosan - PLA composite into deionized water. After stirring and dissolving evenly, add modified silica. After ultrasonic treatment and uniform dispersion, add polyethylene wax, raise the temperature to 40 - 60 °C, and stir and mix evenly to obtain a carrier solution; S3: Stir the mixed active solution prepared in step S1 at a speed of 2000 - 3000 rpm for 30 - 60 min, filter it through a 0.45 μm filter membrane, add β - cyclodextrin, spray - dry, collect the dried powder, and cool it to room temperature to obtain the herbicide composition; Preferably, in step S3, the specific parameters of the spray - drying are set as 30 - 40 °C, hot - air temperature 100 - 110 °C, spray pressure 1 - 2 bar, and drying time 10 - 20 min.

[0010] The beneficial effects of the present invention are as follows: The present invention provides an efficient herbicide composition. By combining triazine herbicides (prometryn, simetryn) with sulfonylurea herbicides (pretilachlor, thifensulfuron-methyl, florasulam), different mechanisms of action are covered, enhancing the herbicidal effect, expanding the herbicidal spectrum, and effectively reducing the risk of the emergence of weed resistance. Natural plant extracts (clove oil, eucalyptus oil, and menthol) are added to the formulation in a reasonable ratio. Their volatile compounds can temporarily disrupt the integrity and fluidity of plant cell membranes, making it easier for chemical herbicide molecules to penetrate the cell membranes and enter the plant interior, thereby improving the absorption efficiency and bioavailability of the herbicides. In addition, natural plant extracts have good biodegradability and can be rapidly degraded in soil and water bodies, reducing the environmental persistence of the herbicides. Moreover, their active compounds have antibacterial and antifungal properties, inhibiting the reproduction of pathogenic microorganisms in the soil and indirectly protecting the health of crops. In terms of synergistic adjuvants, dimethyl sulfoxide (DMSO) is used as a powerful penetrant, acting together with menthol to significantly enhance the permeability of herbicide molecules, enabling them to enter plant tissues more rapidly and deeply, and improving the killing efficiency. The surfactant and the oil-soluble components in the natural extract jointly stabilize the emulsion, ensuring the uniform distribution of the active ingredients during application; citric acid, as a chelating agent, effectively chelates metal ions in the soil, preventing them from reacting with the herbicides and stabilizing the active ingredients. Regarding the use of chitosan-PLA composites, hydrophobically modified silica, and polyethylene wax as carrier components; the chitosan-PLA composite, as a degradable carrier, has a sustained-release property, ensuring the continuous release of the active ingredients in the target area, prolonging the drug efficacy time, reducing the application frequency, and being able to gradually degrade after application, reducing the long-term pollution of soil and water bodies. Due to its high specific surface area and porous structure, hydrophobically modified silica provides more active sites for drug loading and carrier functionalization, enhancing the persistence of the herbicide, and ensuring its uniform dispersion in the hydrophobic carrier through hydrophobic modification, avoiding agglomeration phenomena and ensuring the uniform release of the herbicide. Polyethylene wax, due to its excellent hydrophobicity, chemical and thermal stability, and good mechanical strength, forms a waterproof barrier, further reducing the volatilization and leaching loss of the herbicide, ensuring its effective action on weeds under rainwashing, and protecting the health of the agricultural ecosystem. Through emulsification technology, various active ingredients and carrier components are uniformly dispersed in the aqueous and oil phases to form a stable water-in-oil emulsion, which is then rapidly dried by spray drying technology and converted into dry powders or granules. The rapid drying process reduces the thermal degradation and chemical reactions of the active ingredients, maintaining their high efficiency, while forming fine particles, optimizing the release characteristics and application effects of the herbicide; the powders after spray drying are easy to store and transport, reducing the volatilization loss and degradation risk of the active ingredients, and enhancing the convenience and efficiency of application.

[0011] Overall, the present invention combines multiple active ingredients, carrier technology, and emulsification and spray drying technology to achieve an efficient, environmentally friendly, economical, and long-lasting herbicidal effect, meeting the requirements of modern agriculture for high-performance and sustainable herbicides. Description of the Drawings

[0012] To more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only those of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0013] Figure 1 It is the test result of the long-term stability of the herbicide compositions prepared in Examples 1-3 and Comparative Examples 1-5 of the present invention. Detailed Embodiments

[0014] The following will clearly and completely describe the technical solutions of the present invention in combination with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of them; based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention. It should be noted that unless otherwise specified, the raw materials involved in the present invention are purchased through conventional commercial channels.

[0015] Example 1: A highly efficient herbicide composition, which consists of active ingredient A and carrier ingredient B; the composition of active ingredient A includes the following components: 25 parts of prometryn, 30 parts of simetryn, 5 parts of pretilachlor, 5 parts of thifensulfuron-methyl, 6 parts of florasulam, 3 parts of plant extract, and 1 part of synergistic adjuvant; the composition of carrier ingredient B includes the following components: 3 parts of chitosan-PLA composite, 1 part of modified silica, 2 parts of polyethylene wax, and 0.3 part of β-cyclodextrin.

[0016] The plant extract is obtained by formulating clove oil, eucalyptus oil, and menthol in a ratio of 0.25:0.3:0.45.

[0017] The synergistic adjuvant consists of 0.3 part of penetrant, 0.3 part of surfactant, and 0.4 part of chelating agent.

[0018] The specific preparation steps of the chitosan-PLA composite are as follows: A1: Add 5 g of chitosan and 0.5 g of Tween-80 to 400 mL of 1 wt% acetic acid solution, heat to 50 °C, and stir until dissolved uniformly to obtain a chitosan solution; add 10 g of polylactic acid to 300 mL of dichloromethane, and stir until dissolved uniformly to obtain a polylactic acid solution; A2: Add the 300 mL of polylactic acid solution prepared in step A1 to 300 mL of chitosan solution, stir at a speed of 1000 rpm for 30 min, then add 3 mL of glutaraldehyde, and continue to stir for 1 h to obtain a mixed emulsion; add the mixed emulsion to 600 mL of cold water, continuously stir for 1 h, centrifuge, filter, wash with absolute ethanol, and dry at 70 °C for 6 h to obtain a chitosan-PLA composite; The specific preparation steps of the modified silica are as follows: B1: Add 10 g of silica to 40 mL of absolute ethanol, ultrasonically clean for 30 min, filter, dehydrate with anhydrous sodium sulfate for 1 h, and dry at 60 °C for 6 h to obtain pretreated silica; mix 1 mL of octyltriethoxysilane, 5 mL of absolute ethanol, and 5 mL of anhydrous toluene, and stir to mix evenly to obtain a mixed solution; B2: Heat the mixed solution prepared in step B1 to 50 °C, then slowly add the 10 g of pretreated silica powder prepared in step B1, continuously stir for 2 h, centrifuge, filter, wash repeatedly with absolute ethanol 3 times, and dry at 50 °C for 4 h to obtain modified silica; The specific preparation steps of the herbicide composition are as follows: S1: Weigh prometryn, simetryn, pretilachlor, thifensulfuron-methyl, and florasulam in proportion and add them to an ethanol solution, stir at a speed of 300 rpm for 30 min, then add the plant extract, continue to stir for 10 min, and then slowly add the synergistic adjuvant, and continue to stir for 20 min to obtain a mixed active solution; S2: Add the chitosan-PLA composite to deionized water, stir to dissolve evenly, add the modified silica, ultrasonically disperse evenly, add polyethylene wax, raise the temperature to 40 °C, and stir to mix evenly to obtain a carrier solution; S3: Stir the mixed active solution prepared in step S1 at a speed of 2000 rpm for 30 min, filter through a 0.45 μm filter membrane, add β-cyclodextrin, and spray dry. The specific parameters are set as 30 °C, hot gas temperature 100 °C, spray pressure 1 bar, and drying time 20 min. Collect the dried powder, cool to room temperature to obtain the herbicide composition.

[0019] Example 2: A highly effective herbicide composition, which consists of active ingredient A and carrier ingredient B; the composition of active ingredient A includes the following components: 35 parts of prometryn, 40 parts of simetryn, 8 parts of pretilachlor, 6 parts of thifensulfuron-methyl, 8 parts of florasulam, 5 parts of plant extract, and 2 parts of synergistic adjuvant; the composition of carrier ingredient B includes the following components: 4 parts of chitosan-PLA composite, 2 parts of modified silica, 2.5 parts of polyethylene wax, and 0.5 part of β-cyclodextrin.

[0020] The plant extract is obtained by formulating clove oil, eucalyptus oil and menthol in a ratio of 0.25:0.3:0.45.

[0021] The synergistic adjuvant is composed of 0.6 parts of penetrant, 0.5 parts of surfactant and 0.9 parts of chelating agent.

[0022] The specific preparation steps of the chitosan-PLA composite are as follows: A1: Add 5 g of chitosan and 0.8 g of Tween-80 to 250 mL of 1 wt% acetic acid solution, heat to 55 °C, stir and dissolve evenly to obtain a chitosan solution; add 10 g of polylactic acid to 300 mL of dichloromethane, stir and dissolve evenly to obtain a polylactic acid solution; A2: Add the 250 mL of polylactic acid solution prepared in step A1 to the 250 mL of chitosan solution, stir at a speed of 1500 rpm for 30 min, then add 3 mL of glutaraldehyde, continue to stir for 1 h to obtain a mixed emulsion; add the mixed emulsion to 750 mL of cold water, continuously stir for 1.5 h, centrifuge, filter, wash with absolute ethanol, and dry at 70 °C for 6 h to obtain the chitosan-PLA composite; The specific preparation steps of the modified silica are as follows: B1: Add 10 g of silica to 50 mL of absolute ethanol, ultrasonically clean for 30 min, filter, dehydrate with anhydrous sodium sulfate for 1 h, and dry at 60 °C for 6 h to obtain pretreated silica; mix 1.3 mL of octyltriethoxysilane, 8 mL of absolute ethanol and 8 mL of anhydrous toluene, and stir and mix evenly to obtain a mixed solution; B2: Heat the mixed solution prepared in step B1 to 55 °C, then slowly add the 10 g of pretreated silica powder prepared in step B1, continuously stir for 3 h, centrifuge, filter, wash repeatedly with absolute ethanol 3 times, and dry at 60 °C for 5 h to obtain the modified silica; The specific preparation steps of the herbicide composition are as follows: S1: Weigh prometryn, simetryn, pretilachlor, thifensulfuron-methyl and florasulam in proportion and add them to an ethanol solution, stir at a speed of 400 rpm for 50 min, then add the plant extract, continue to stir for 15 min, and then slowly add the synergistic adjuvant, continue to stir for 25 min to obtain a mixed active solution; S2: Add the chitosan-PLA composite to deionized water, stir and dissolve evenly, then add the modified silica, ultrasonically treat to disperse evenly, add polyethylene wax, raise the temperature to 50 °C, and stir and mix evenly to obtain a carrier solution; S3: Stir the mixed active solution prepared in step S1 at a speed of 2500 rpm for 50 min, filter it through a 0.45 μm filter membrane, add β-cyclodextrin, and perform spray drying. The specific parameter settings are 35°C, hot gas temperature 105°C, spray pressure 2 bar, and drying time 12 min. Collect the dried powder and cool it to room temperature to obtain the herbicide composition.

[0023] Example 3: A highly effective herbicide composition, whose composition includes active ingredient A and carrier ingredient B; the composition of active ingredient A includes the following components: 30 parts of prometryn, 35 parts of simetryn, 10 parts of pretilachlor, 8 parts of thifensulfuron-methyl, 10 parts of flucarbazone-sodium, 4 parts of plant extract, and 1.5 parts of synergistic adjuvant; the composition of carrier ingredient B includes the following components: 5 parts of chitosan-PLA composite, 1.5 parts of modified silica, 3 parts of polyethylene wax, and 0.4 part of β-cyclodextrin.

[0024] The plant extract is obtained by formulating clove oil, eucalyptus oil, and menthol in a ratio of 0.25:0.3:0.45.

[0025] The synergistic adjuvant consists of 0.5 part of penetrant, 0.4 part of surfactant, and 0.6 part of chelating agent.

[0026] The specific preparation steps of the chitosan-PLA composite are as follows: A1: Add 5 g of chitosan and 1 g of Tween-80 to 500 mL of 1 wt% acetic acid solution, heat to 60°C, and stir until dissolved evenly to obtain a chitosan solution; add 10 g of polylactic acid to 300 mL of dichloromethane, and stir until dissolved evenly to obtain a polylactic acid solution. A2: Add the 300 mL of polylactic acid solution prepared in step A1 to the 300 mL of chitosan solution, stir at a speed of 2000 rpm for 30 min, then add 3.5 mL of glutaraldehyde, and continue to stir for 1 h to obtain a mixed emulsion; add the mixed emulsion to 750 mL of cold water, continuously stir for 2 h, centrifuge, filter, wash with absolute ethanol, and dry at 70°C for 6 h to obtain the chitosan-PLA composite. The specific preparation steps of the modified silica are as follows: B1: Add 10 g of silica to 45 mL of absolute ethanol, perform ultrasonic cleaning for 30 min, filter, dehydrate with anhydrous sodium sulfate for 1 h, and dry at 60°C for 6 h to obtain pretreated silica; mix 1.5 mL of octyltriethoxysilane, 10 mL of absolute ethanol, and 10 mL of anhydrous toluene, and stir and mix evenly to obtain a mixed solution. B2: Heat the mixed solution prepared in step B1 to 60 °C, then slowly add 10 g of pretreated silica powder prepared in step B1, continuously stir for 4 h, centrifuge, filter, repeat washing with absolute ethanol 3 times, and dry at 55 °C for 6 h to obtain modified silica; The specific preparation steps of the herbicide composition are as follows: S1: Weigh prometryn, simetryn, pretilachlor, thifensulfuron-methyl, and florasulam in proportion and add them to an ethanol solution. Stir at a speed of 500 rpm for 60 min, then add the plant extract, continue to stir for 20 min, and then slowly add the synergistic adjuvant, continue to stir for 30 min to obtain a mixed active solution; S2: Add the chitosan-PLA composite to deionized water. After stirring and dissolving evenly, add the modified silica. After ultrasonic treatment and dispersion evenly, add polyethylene wax, raise the temperature to 60 °C, and stir and mix evenly to obtain a carrier solution; S3: Stir the mixed active solution prepared in step S1 at a speed of 3000 rpm for 60 min, filter with a 0.45 μm filter membrane, add β-cyclodextrin, and spray dry. The specific parameters are set as 40 °C, hot air temperature 110 °C, spray pressure 1.5 bar, and drying time 10 min. Collect the dried powder, cool to room temperature to obtain the herbicide composition.

[0027] Comparative Example 1: The operation of Comparative Example 1 is basically the same as that of Example 2, except that modified silica is not added in Comparative Example 1.

[0028] Comparative Example 2: The operation of Comparative Example 2 is basically the same as that of Example 2, except that the plant extract is not added in Comparative Example 2.

[0029] Comparative Example 3: The operation of Comparative Example 3 is basically the same as that of Example 2, except that simetryn is not added in Comparative Example 3.

[0030] Comparative Example 4: The operation of Comparative Example 4 is basically the same as that of Example 2, except that pretilachlor, thifensulfuron-methyl, and florasulam are not added in Comparative Example 4.

[0031] Comparative Example 5: The operation of Comparative Example 5 is basically the same as that of Example 2, except that in Comparative Example 5, all substances are directly mixed to prepare the herbicide composition.

[0032] Performance test: Long-term stability test: Place the herbicide compositions prepared in Examples 1-3 and Comparative Examples 1-5 of the present invention at a temperature of 45 °C and a relative humidity of 80% for 7 and 15 days, and respectively test the percentage reduction of the prometryn content. The results are as Figure 1 shown.

[0033] ByFigure 1 The results show that the herbicide composition prepared by the present invention has excellent thermal stability. Among them, the formulation of Example 2 has excellent thermal performance. The combined use of triazine herbicides (prometryn, simetryn) and sulfonylurea herbicides (pretilachlor, thifensulfuron-methyl, florasulam) forms a complex microenvironment to a certain extent, alleviating the degradation of single components. From the results of Comparative Example 5 and Example 2, it can be seen that without optimized processes such as emulsification and spray drying, the active ingredients and carriers are unevenly dispersed, and the sustained-release and protection effects are greatly weakened, and the herbicide is significantly degraded under the influence of high temperature and high humidity. From the results of Comparative Example 1 and Example 2, it can be seen that modified silica helps to form a hydrophobic environment and a porous structure, improving the persistence and stability of the herbicide. After removal, the herbicide is more susceptible to the influence of high temperature and high humidity conditions, and degradation reactions such as hydrolysis and oxidation are more likely to occur, resulting in obvious degradation.

[0034] Herbicidal effect test: The herbicide compositions prepared in Example 2 and Comparative Examples 1-5 were diluted 100 times and 200 times respectively and then applied to barnyard grass, green foxtail, purslane, false hellebore and redroot amaranth. The results are shown in Tables 1 and 2 below.

[0035] Table 1. Herbicidal effect results of herbicide compositions with different formulations diluted 100 times

[0036] Table 2. Herbicidal effect results of herbicide compositions with different formulations diluted 200 times

[0037] As can be seen from the results in Table 1 and Table 2, the herbicide prepared by rationally mixing various types of herbicides in the present invention has excellent herbicidal effects. In particular, the formulation in Example 2 has the best effect under 100-fold dilution. By combining various triazine herbicides with sulfonylurea herbicides and cooperating with natural extracts, an efficient herbicidal effect is effectively achieved. From the results of Comparative Example 1 and Example 2, the lack of modified silica may lead to difficulties in the uniform distribution of the herbicide in the carrier, a decline in the sustained-release characteristics, and uneven release of the active ingredients, resulting in a weakening of the overall herbicidal effect and persistence. From the results of Comparative Example 2 and Example 2, the absence of plant extracts, especially menthol, affects the ability of the herbicide to penetrate the plant cell membrane to a certain extent, and the absorption rate and depth are affected, leading to an impact on the killing efficiency. From the results of Comparative Example 3 and Example 2, the lack of simetryne results in the synergistic effect of the herbicide on inhibiting photosynthesis, narrowing the herbicidal spectrum and affecting the overall herbicidal effect and resistance management ability. From the results of Comparative Example 4 and Example 2, after removing the sulfonylurea active ingredient, the formulation only contains triazine herbicides, lacking the superimposed effect of multiple targets and weakening the comprehensive inhibitory ability of the herbicide. From the results of Comparative Example 5 and Example 2, direct mixing lacks a stable microstructure and carrier encapsulation, affecting the uniformity and stability of the active ingredients during application, and thus leading to an impact on the herbicidal performance.

[0038] Environment-friendly test: Pass the standard soil through a 2 mm sieve, then mix it with distilled water in a ratio of 4:6, and fill 5 culture containers respectively (the herbicide compositions prepared in Example 2 and Comparative Examples 3-5 and the control group prometryn are diluted 100 times and sprayed). The soil thickness is about 10 cm. 20 earthworms are selected and placed in each culture container. Place the culture containers in an incubator and maintain a temperature of 20 ± 2 °C. The test is carried out in the dark. Observe once every 24 h, and record the number of earthworms once a week after the third day. The test lasts for 38 days, and the results are shown in Table 3 below.

[0039] Table 3. Results of the effects of herbicides with different formulations on the survival rate of earthworms

[0040] As can be seen from the results in Table 3, the herbicide prepared by the present invention has excellent environmental stability. Compared with prometryn directly applied in the control group, there is no obvious impact on the survival rate of earthworms, an animal in the soil, during long-term tests, indicating excellent environmental friendliness. From the results of Comparative Example 3 and Example 2, it can be seen that after the absence of simetryn, the multiple action mechanisms of the formulation are weakened, which may cause some active ingredients to affect environmental organisms in a more direct manner, resulting in a slight decrease in the survival rate of earthworms during long-term observation. From the results of Comparative Example 4 and Example 2, it can be seen that the sulfonylurea herbicide and triazine herbicide in the original formulation together constitute a combined action mechanism, which to a certain extent controls the release rhythm and environmental behavior of active ingredients through mutual influence. Retaining only part of the herbicide reduces the mechanism diversity and synergistic buffering effect, which may lead to a more obvious potential impact of the active substance on the non-target organism, earthworms. From the results of Comparative Example 5 and Example 2, it can be seen that when all substances are simply mixed directly without optimized emulsification and drying steps, the active ingredients may be rapidly released in the initial stage, forming a relatively high local concentration, which may therefore lead to the death of earthworms relatively early in the test.

[0041] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made therein without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A highly effective herbicide composition, characterized in that: The composition includes active ingredient A and carrier ingredient B; the composition of the active ingredient A includes the following components: 25-35 parts of promethazine, 30-40 parts of simethoate, 5-10 parts of pretilachlor, 5-8 parts of thiosulfuron-methyl, 6-10 parts of fomesulam, 3-5 parts of plant extracts and 1-2 parts of synergistic aids; the composition of the carrier ingredient B includes the following components: 3-5 parts of chitosan-PLA complex, 1-2 parts of modified silicon dioxide, 2-3 parts of polyethylene wax and 0.3-0.5 parts of beta-cyclodextrin.

2. A highly effective herbicide composition according to claim 1, characterized in that: The plant extract is prepared by mixing clove oil, eucalyptus oil and menthol in a ratio of 0.25:0.3:0.

45.

3. A highly effective herbicide composition according to claim 2, characterized in that: The synergistic aid is composed of 0.3-0.6 parts of a penetrant, 0.3-0.5 parts of a surfactant and 0.4-0.9 parts of a chelating agent; the penetrant is dimethyl sulfoxide; the surfactant is any one of Tween-80, Span-80 and glyceride; and the chelating agent is citric acid.

4. A highly effective herbicide composition according to claim 3, characterized in that: The specific preparation steps of the chitosan-PLA complex are as follows: A1: adding chitosan and Tween-80 to an acetic acid solution, heating, stirring and dissolving uniformly to obtain a chitosan solution; adding polylactic acid to dichloromethane, stirring and dissolving uniformly to obtain a polylactic acid solution; A2: Add the polylactic acid solution prepared in step A1 to the chitosan solution, stir, then add glutaraldehyde, continue to stir evenly to obtain a mixed emulsion; add the mixed emulsion into cold water, continue to stir, centrifuge, filter, wash with anhydrous ethanol, and dry to obtain a chitosan-PLA complex.

5. A highly effective herbicide composition according to claim 4, characterized in that: In step A1, the ratio of the amount of chitosan, Tween-80 and acetic acid solution is 1g:0.1-0.2g:50-100mL; the ratio of the amount of polylactic acid and dichloromethane is 1g:30mL; in step A2, the ratio of the amount of polylactic acid solution, chitosan solution, glutaraldehyde and cold water is 1:1:0.005-0.006:2-3.

6. A highly effective herbicide composition according to claim 5, characterized in that: The specific preparation steps of the modified silicon dioxide are as follows: B1: adding silica to anhydrous ethanol, ultrasonically cleaning, filtering, dehydrating with anhydrous sodium sulfate, and drying to obtain pretreated silica; mixing octyltriethoxysilane, anhydrous ethanol, and anhydrous toluene, stirring and mixing evenly to obtain a mixed solution; B2: Heat the mixed solution prepared in step B1, then slowly add the pretreated silica powder prepared in step B1, continue stirring, centrifuge, filter, repeatedly wash with anhydrous ethanol, and dry for 4 to 6 hours to obtain modified silica.

7. A highly effective herbicide composition according to claim 6, characterized in that: In step B1, the ratio of the amount of the silica to anhydrous ethanol is 1 g:4-5 mL; in step B2, the ratio of the amount of octyltriethoxysilane, anhydrous ethanol, anhydrous toluene and pretreated silica is 0.1-0.15 mL: 0.5-1 mL: 0.5-1 mL: 1 g.

8. A method for preparing a high-efficiency herbicide composition according to any one of claims 1 to 7, characterized in that: The specific preparation steps are as follows: S1: Weigh prometryn, simetryn, pretilachlor, thiosulfuron and fomesulam in proportion and add them to the ethanol solution, stir, then add the plant extract, continue to stir, then slowly add the synergist, continue to stir, and obtain a mixed active solution; S2: adding chitosan-PLA complex to deionized water, stirring and dissolving uniformly, adding modified silica, ultrasonically dispersing uniformly, adding polyethylene wax, raising the temperature, stirring and mixing uniformly, and obtaining a carrier solution; S3: stirring the mixed active solution prepared in step S1, filtering with a filter membrane, adding β-cyclodextrin, spray drying, collecting the dried powder, and cooling to room temperature to obtain a herbicide composition.

9. The method for preparing a highly effective herbicide composition according to claim 8, characterized in that: In step S3, the specific parameters of the spray drying are set to 30-40°C, hot air temperature 100-110°C, spray pressure 1-2 bar, and drying time 10-20 min.

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