Herbicidal Compositions and Their Applications

Abstract

This invention relates to the field of pesticide technology and discloses a herbicidal composition and its application. The active ingredients of the herbicidal composition include mesosulfuron-methyl, isoproturon, and metribuzin. The herbicidal composition can be applied to control annual weeds in wheat-growing fields. This invention provides a ternary compound composition of mesosulfuron-methyl, isoproturon, and metribuzin, and provides a method for preparing a dispersible oil suspension and preferred adjuvants, improving product stability and enabling it to withstand high and low temperature ranges. Furthermore, this invention can withstand different water qualities such as C-type water, D-type water, and 3WHO-type water, and the product has a high suspension rate, which can subsequently meet the needs of different countries and regions, facilitating widespread application.

Description

Technical Field

[0001] This invention relates to the field of pesticide technology, specifically to herbicidal compositions and their applications. Background Technology

[0002] Methsulfuron-methyl belongs to the sulfonylurea herbicide class and has systemic properties. It is mainly absorbed through the stems and leaves of plants, inhibiting the activity of acetolactate synthase in the plant, thus hindering the synthesis of branched-chain amino acids, inhibiting cell division, and causing sensitive plants to die. It has a broad spectrum of control and is mainly used to control grassy weeds and some broadleaf weeds in wheat fields.

[0003] Isoproturon is a selective herbicide belonging to the substituted urea class. It mainly achieves its control effect by inhibiting the photosynthesis of weeds. It is suitable for fields of cereal crops such as wheat and barley. It can effectively control annual broadleaf weeds and some grass weeds, and also has the effects of soil sealing and early post-emergence weed control.

[0004] Mefenoxam belongs to the triazine class of herbicides and is suitable for fields of crops such as soybeans, corn, potatoes, peanuts, and wheat. It can effectively control annual broadleaf weeds and some grass weeds and can be sprayed before sowing, after sowing, before emergence, or before transplanting.

[0005] Herbicides containing a single active ingredient often have varying degrees of drawbacks in agricultural weed control, such as a narrow spectrum of weed control, the tendency for weeds to develop resistance after continuous use, and increased environmental pollution from frequent applications. Appropriately formulated herbicides, on the other hand, offer advantages such as strong complementarity, significant synergistic effects, a broader control spectrum, and reduced application rates. However, if the active ingredients are not selected properly, antagonism and difficulties in achieving the desired formulation performance can easily occur after formulation. Furthermore, the more active ingredients in a formulation, the greater the difficulty in developing the formulation. Currently, most herbicides on the market are single-agent or binary formulations of related active ingredients; ternary formulations are less common, and there are currently no reports on ternary formulations of mesosulfuron-methyl, isoproturon, and metribuzin, or their formulations. Summary of the Invention

[0006] The purpose of this invention is to overcome the problems existing in the prior art and to provide a weed control composition and its application.

[0007] Currently, there are reports on combinations of mesosulfuron-methyl + isoproturon and isoproturon + metribuzin, but no reports on combinations of mesosulfuron-methyl, isoproturon, and metribuzin. Regarding formulations, there are also no reports on ternary mixtures such as dispersible oil suspensions, water-dispersible granules, wettable powders, or dry suspensions.

[0008] The first aspect of the present invention provides a herbicidal composition, wherein the active ingredients of the herbicidal composition include mesosulfuron-methyl, isoproturon, and metribuzin.

[0009] In some embodiments of the present invention, the weight ratio of mesosulfuron-methyl, isoproturon, and metribuzin in the herbicidal composition is 1:50-150:5-20. Experimental verification has shown that within this weight ratio range, the combination of mesosulfuron-methyl, isoproturon, and metribuzin exhibits a significant synergistic effect. Preferably, the synergistic effect is even better when the weight ratio of mesosulfuron-methyl, isoproturon, and metribuzin is 1:50-100:10-20, and the herbicidal effect is optimal when the weight ratio is 1:100:14. In this invention, the weight ratio may also be 1:50:5, or 1:50:20, or 1:150:5, or 1:150:20, or 1:150:10, or 1:120:15, or 1:60:8, or 1:55:8, or 1:70:5, or any value within the range of any two of the above values.

[0010] The herbicidal composition may also include a safener, preferably pyrazole herbicides, and the mass content of pyrazole herbicides is preferably 2-5 times that of mesosulfuron-methyl.

[0011] In some embodiments of the present invention, the weight percentage of the active ingredient in the herbicidal composition is 5-80%, or 10-38.4%, or 32.2%.

[0012] In some embodiments of the present invention, the weed-control composition further includes excipients.

[0013] In some embodiments of the present invention, the excipients are selected from at least one of emulsifiers, dispersants, thickeners and dispersion media.

[0014] In some embodiments of the present invention, the herbicidal composition can be formulated into any agriculturally permissible formulation, such as at least one of water-dispersible granules, wettable powders, dispersible oil suspensions, and dry suspensions. The excipients selected vary depending on the formulation. Excipients can be selected from those reported in the prior art, but different excipients will result in differences in formulation performance and herbicidal efficacy.

[0015] Based on the aforementioned active ingredients of pesticides, this invention has conducted further research and successfully developed a dispersible oil suspension formulation suitable for the ternary herbicidal components of mesosulfuron-methyl, isoproturon, and metribuzin. Furthermore, through extensive research and experimentation, excipients such as dispersants, emulsifiers, and thickeners were screened, resulting in a dispersible oil suspension with excellent performance and herbicidal effect.

[0016] In some embodiments of the present invention, the dispersible oil suspension comprises the following components by weight percentage: 10-60% active ingredient, 8-35% emulsifier, 1-5% dispersant, 1-6% thickener, and 100% dispersion medium.

[0017] In some embodiments of the present invention, the active ingredient is 20-60%, or 25-60%, or 30-45%.

[0018] In some embodiments of the present invention, the emulsifier is 15-30%.

[0019] In some embodiments of the present invention, the dispersant is 2-5%.

[0020] In some embodiments of the present invention, the thickener is 2-5%.

[0021] In some embodiments of the present invention, the emulsifier is selected from at least one of alkylbenzene sulfonate, fatty amine polyoxyethylene ether, castor oil polyoxyethylene ether, polyoxyethylene dehydrated sorbitan monooleate, styrene-based phenol polyoxyethylene ether, and polyoxyethylene ether phosphate; or, the emulsifier is a mixture of alkylbenzene sulfonate and polyoxyethylene dehydrated sorbitan monooleate in a mass ratio of 1:2-4. The performance is optimal when the emulsifier is a mixture of alkylbenzene sulfonate and polyoxyethylene dehydrated sorbitan monooleate in a mass ratio of 1:2-4.

[0022] In some embodiments of the present invention, the dispersant is selected from at least one of alkyl naphthalene sulfonate formaldehyde condensate, polyoxyethylene-polyoxypropylene block copolymer, calcium lignosulfonate and modified polyacrylic acid copolymer, preferably polyoxyethylene-polyoxypropylene block copolymer.

[0023] In some embodiments of the present invention, the thickener is selected from at least one of silica, organobentonite and urea; or, the thickener comprises silica and organobentonite in a weight ratio of 2:1.

[0024] In some embodiments of the present invention, the dispersion medium is selected from at least one of methyl oleate, castor oil, soybean oil, rapeseed oil methyl ester, and solvent oil. The dispersion media used in the present invention are all environmentally friendly green solvents, which are more environmentally friendly and have good compatibility with various components, thus improving product stability.

[0025] When the above-mentioned excipient components and contents are selected, a dispersible oil suspension formulation with good stability and excellent performance can be obtained, and the efficacy of mesosulfuron-methyl, isoproturon, and metribuzin can be fully utilized.

[0026] In some embodiments of the present invention, the dispersible oil suspension can be prepared according to preparation methods disclosed in the prior art. In the present invention, the preparation method of the dispersible oil suspension is as follows: after a first mixing of the dispersion medium, thickener, emulsifier, and dispersant, an active ingredient (and optionally a safener) is added for a second mixing, and finally, the mixture is ground to a particle size D. 90The dispersible oil suspension was obtained with a particle size of less than 8µm.

[0027] In some embodiments of the invention, the second mixing is performed by shearing.

[0028] In some embodiments of the present invention, the shearing conditions include: a speed of 1000-10000 r / min and a time of 10-30 min. At this shearing speed, thorough mixing and emulsification can be achieved relatively quickly. The faster the shearing speed, the shorter the time required. The shearing time is generally 10-30 min.

[0029] In the above preparation method, grinding can be performed using any grinding method disclosed in the prior art, such as grinding under zirconia bead milling media. After grinding, the particle size is measured using a laser particle size analyzer until the particle size D is reached. 90 Up to 8µm.

[0030] A second aspect of the present invention provides the application of the described herbicidal composition in controlling annual weeds in wheat crop fields.

[0031] In some embodiments of the present invention, the annual weed is selected from at least one of the following: Alopecurus aequalis (e.g., Alopecurus thunbergii), jointed barley, wild oats, shepherd's purse, and ryegrass.

[0032] The beneficial technical effects achieved by the present invention through the above technical solution are as follows:

[0033] (1) The present invention combines the pesticide active ingredients mesosulfuron-methyl, isoproturon and metribuzin. The three ingredients do not antagonize each other when mixed, and the weed control spectrum is expanded and the weed control efficiency is improved. It shows a significant synergistic effect and can be used to control annual weeds in wheat fields.

[0034] (2) The ternary herbicidal composition of mesosulfuron-methyl, isoproturon and metribuzin provided by the present invention has a good synergistic effect within a specific ratio, and the control effect is higher than that of single agent and binary mixture. The dosage is small, weed resistance is avoided, the drug's duration of action is extended, and it is conducive to environmental sustainable development.

[0035] (3) The herbicidal composition of the present invention can be made into a dispersible oil suspension. By selecting excipients, a dispersible oil suspension with good stability and excellent performance can be obtained, which can greatly promote the efficacy of the active ingredients of pesticides.

[0036] (4) The present invention improves product stability and can withstand high and low temperature ranges from -15℃ to 65℃, effectively solving the impact of environmental changes on product quality during transportation. Detailed Implementation

[0037] The following embodiments are further illustrations of the present invention and serve as explanations of the technical content of the present invention, but the essence of the present invention is not limited to the embodiments described below.

[0038] Unless otherwise specified, all percentages below are by weight.

[0039] In the following examples, mesosulfuron-methyl, isoproturon, and metribuzin are all commercially available, and other adjuvants are also commercially available products.

[0040] The present invention will be further described in detail below through examples.

[0041] Example 1: Indoor toxicity determination

[0042] The synergistic effect of mesosulfuron-methyl, isoproturon, and metsulfuron-methyl was determined using an indoor toxicity assay. The indoor toxicity assay was conducted according to the Sun Yunpei method to determine the co-toxicity coefficient (CTC) of the herbicides when mixed in a certain proportion. A CTC < 80 indicated an antagonistic effect, 80 ≤ CTC ≤ 120 indicated an additive effect, and CTC > 120 indicated a synergistic effect.

[0043] Test reagents: Mesosulfuron-methyl, isoproturon, and metribuzin were provided by Shandong Weifang Runfeng Chemical Co., Ltd.

[0044] Experimental Design: After preliminary testing to determine the effective inhibition concentration range of each herbicide, a series of concentration treatments were set for each herbicide according to the content of its active ingredient, with a water control included. Following the "Guidelines for Indoor Bioassay Testing of Pesticides (Herbiceps)", 21 days after foliar spraying, the above-ground parts of the large spikelets of *Alopecurus aequalis* in each treatment were cut and weighed fresh. The fresh weight inhibition rate was calculated as follows: Fresh weight inhibition rate = (Fresh weight of control group - Fresh weight of treatment group) / Fresh weight of control group × 100%. The dose value (ED) at which fresh weight inhibition reached 50% was calculated for each treatment. 50 (in g.ai / ha), and its co-toxicity coefficient was obtained using the method for calculating co-toxicity proposed by Sun Yunpei et al. (1960).

[0045] The calculation formula is as follows (using mesosulfuron-methyl as the standard agent, with a toxicity index of 100):

[0046] The toxicity index (TI) of isoproturon is equal to the ED of mesosulfuron-methyl. 50 / Isoproterone ED 50 ×100.

[0047] The toxicity index (TI) of metsulfuron-methyl is equal to the ED of mesosulfuron-methyl. 50 / Dysprozil ED 50 ×100.

[0048] Actual Toxicity Index (ATI) of M = ED of mesosulfuron-methyl50 / M of ED 50 ×100.

[0049] Theoretical toxicity index (TTI) of M = TTI of mesosulfuron-methyl × P 甲基二磺隆 +Isoproturon TI×P 异丙隆 +Methotributazone TI×P 嗪草酮 .

[0050] Cotoxicity coefficient (CTC) of M = ATI of M / TTI of M × 100.

[0051] In the formula: M is a mixture of mesosulfuron-methyl, isoproturon, and metribuzin in different proportions;

[0052] P 甲基二磺隆 This represents the proportion of mesosulfuron-methyl in the mixture;

[0053] P 异丙隆 This represents the proportion of isoproturon in the mixture;

[0054] P 嗪草酮 This represents the proportion of methamidophos in the mixture.

[0055] This invention relates to a composition of three active pharmaceutical ingredients. The theoretical toxicity index (TTI) of M can also be calculated by adding the toxicity index of the binary mixture to the toxicity index of the other single agent: Theoretical toxicity index (TTI) of M = ATI of the binary mixture × P 二元混剂 +Another single-dose TI×P 另一单剂 (In this formula, the binary mixture ATI is the ATI when components A+B (or B+C or C+A) are used together (= ED of mesosulfuron-methyl) 50 / ED of component (A+B) (or B+C or C+A) 50 ×100), P 二元混剂 The TI is the proportion of component A+B (or B+C or C+A) in the mixture; the other single agent TI is the TI of component C (or A or B), P 另一单剂 The proportion of component C (or A or B) in the mixture is used to illustrate the synergistic effect of the ternary composition of the present invention from multiple perspectives.

[0056] The experimental results are shown in Table 1:

[0057] Table 1. Toxicity test results of combined mesosulfuron-methyl, isoproturon-methyl, and metribuzin on *Alopecurus aequalis*.

[0058] ;

[0059] Continued from Table 1

[0060] ;

[0061] Table 1 shows that mesosulfuron-methyl, isoproturon, and metribuzin have different effects on the ED of *Alopecurus aequalis*. 50 The concentrations were 42.13 g.ai / ha, 376.96 g.ai / ha, and 108.26 g.ai / ha, respectively. When the weight ratio of mesosulfuron-methyl, isoproturon, and metribuzin was 1:50:5, 1:50:20, 1:150:5, 1:150:20, and 1:100:14, the co-toxicity coefficient of the compound composition was greater than 120, showing a synergistic effect. However, when the mass ratio of mesosulfuron-methyl, isoproturon, and metribuzin was 1:40:25, the co-toxicity coefficient was only 113.47, showing an additive effect.

[0062] Compared to binary combinations, the combination of mesosulfuron-methyl, isoproturon, and metribuzin offers several advantages. First, it can effectively control annual weeds in wheat fields, with a wider spectrum of weed control compared to binary combinations. Second, the synergistic effect of the ternary combination is significant, addressing the resistance issues associated with binary combinations and achieving the goal of reducing application while increasing efficacy. It can also delay the development of herbicide resistance in weeds.

[0063] Example 2-12

[0064] Examples 2-12 provide a series of dispersible oil suspensions, with specific formulations shown in Table 2.

[0065] The preparation method of dispersible oil suspension is as follows:

[0066] The dispersion medium, thickener, emulsifier, and dispersant are mixed and dispersed evenly. Then, mesosulfuron-methyl, isoproturon, metribuzin, and the safener pyrazosulfuron (1.0%) are added and thoroughly sheared and mixed. Finally, the mixture is ground to a particle size D. 90 With a particle size of less than 8µm, dispersible oil suspensions of mesosulfuron-methyl, isoproturon, and metribuzin were obtained.

[0067] The specific types of some materials are shown below:

[0068] Castor oil polyoxyethylene ether: EL-40;

[0069] Alkylbenzene sulfonate calcium: Agricultural emulsion 500#;

[0070] Fatty amine polyoxyethylene ether: Ethomeen C;

[0071] Polyoxyethylene sorbitan monooleate: Tween-80;

[0072] Styrene-based phenolic polyoxyethylene ether: Agricultural emulsion 600#;

[0073] Polyoxyethylene ether phosphate: TRST;

[0074] Alkyl naphthalene sulfonate formaldehyde condensate: NNO;

[0075] Polyoxyethylene-polyoxypropylene block copolymer: DOWFAX-D800;

[0076] Sodium lignosulfonate: REAX85A.

[0077] Table 2. Formulation of dispersible oil suspensions (wt%)

[0078] ;

[0079] Continued from Table 2

[0080] ;

[0081] Test Example 1: Physicochemical Indicators of Pharmaceutical Products

[0082] The performance of the dispersible oil suspension products prepared in Examples 2-12 was tested, and the results are shown in Table 3 below.

[0083] The suspension rate was tested according to GB / T 14825-2023, the method for determining the suspension rate of pesticides; the pourability (residue after pouring) was tested according to GB / T 31737-2015, the method for determining the pourability of pesticides; the dispersion stability was tested according to CIPAC MT 180, "Determination of dispersion stability of suspension emulsions"; the thermal storage stability (performance before and after thermal storage) was tested according to GB / T 19136-2021, the method for determining the thermal storage stability of pesticides; and the cold storage stability was tested according to GB / T 19137-2003, the method for determining the low temperature stability of pesticides. The cold storage temperature was adjusted to -15℃ for storage, and after returning to room temperature for 1 day, the appearance and dispersion stability were tested.

[0084] Table 3. Performance Test Results of Dispersible Oil Suspension Products

[0085] ;

[0086] As shown in Table 3, the dispersible oil suspension products prepared by this invention all exhibit high suspension rates, low residual amount after pouring, good dispersion stability, good thermal storage stability, and good cold storage stability. Example 12 showed poor quality both before and after thermal storage; after being stored at 54℃ for 14 days and then transferred to room temperature, the suspension rate decreased and the oil separation rate reached 18%. Examples 2-7 showed slightly worse quality after thermal storage, while Examples 8-11 showed good quality both before and after thermal storage. The test results for cold storage stability were similar. The selection of optimal additives plays a crucial role in product quality.

[0087] Test Example 2: Field Trial Example, Herbal Efficacy Test of Annual Miscellaneous Herbs in Wheat Field

[0088] This experiment was conducted in a farmland on the outskirts of Weicheng District, Weifang City, Shandong Province. The terrain was flat, the land was level, irrigation and drainage facilities were complete, field management was consistent, and fertility was uniform and moderate. Wheat was cultivated by direct seeding. The main weeds in the experimental field were Alopecurus aequalis, jointed goatgrass, wild oats, Desmodium styracifolium, and ryegrass.

[0089] The experiment included eight treatments (using Example 8, Example 12, 20% mesosulfuron-methyl·isoproturon (19.6% isoproturon + 0.4% mesosulfuron-methyl) oil dispersible suspension (commercially available), 45% mesosulfuron-methyl·isoproturon·pyrfluthrin oil dispersible suspension (Formulation Example 13 in CN105475324A), 36% mesosulfuron-methyl·isoproturon·diflubenzuron oil dispersible suspension (Formulation Example 1 in CN111955472A), 36% mesosulfuron-methyl·isoproturon·pyrfluthrin oil dispersible suspension (Formulation 1 in CN116869013A), 33% mesosulfuron-methyl·isoproturon·sulfonylpyrazole suspension emulsion (Example 1 in CN119302308A), and a water control). Each treatment was replicated three times, for a total of 24 plots, each plot being 30 m². 2 The experiment was conducted in a randomized block design. The water control group was sprayed with water without any pesticide, while the remaining experimental areas were treated with pesticides. The pesticide was applied on March 1, 2024, during the wheat's greening stage. The application method was as follows: one application was made using a Gongnong-16 backpack manual sprayer. The pesticide solution was prepared by diluting the formulation dosage with 450 kg of water per hectare, and the calculated solution volume for each plot was then uniformly sprayed. All water used for preparing the pesticide solution was 3% WHO water prepared in the laboratory.

[0090] Thirty days after application, the efficacy of each treatment in controlling weed fresh weight and its safety to wheat were investigated. Method for investigating weed fresh weight control efficacy:

[0091] Thirty days after application, four points were randomly selected from each plot, each 0.25m wide. 2 Weeds were removed, and their fresh weight was measured. The weed control efficacy was calculated based on the fresh weight of the weeds.

[0092] ;

[0093] The results of annual weed control in wheat fields are shown in Table 4 below:

[0094] Table 4. Field efficacy test results of various treatments for controlling annual weeds in wheat fields

[0095] ;

[0096] The experimental results in the table above show that the combination of mesosulfuron-methyl, isoproturon, and metribuzin has a good control effect on annual weeds in wheat fields. Compared with existing binary or similar ternary formulations, the ternary compound formulation of mesosulfuron-methyl, isoproturon, and metribuzin in this invention significantly improves weed control efficacy and applicability. Furthermore, the selection of adjuvants in this invention has a significant impact on the effectiveness of the active ingredients, exhibiting a synergistic effect.

[0097] In addition, based on the observation of the entire field trial, the wheat fields grew well within the experimental dosage range, and no phytotoxicity was observed, indicating that the compound agent did not cause phytotoxicity to wheat.

[0098] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A herbicidal composition, characterized in that, The active ingredients of the herbicidal composition consist of mesosulfuron-methyl, isoproturon, and metribuzin. In the herbicidal composition, the weight ratio of mesosulfuron-methyl, isoproturon, and metribuzin is 1:50-150:5-20.

2. The herbicidal composition according to claim 1, characterized in that, The active ingredient in the herbicidal composition has a weight percentage of 5-80%.

3. The herbicidal composition according to claim 1, characterized in that, The herbicidal composition also includes excipients.

4. The herbicidal composition according to claim 3, characterized in that, The excipients are selected from at least one of emulsifiers, dispersants, thickeners, and dispersion media.

5. The herbicidal composition according to claim 1, characterized in that, The formulation of the herbicidal composition is selected from at least one of water-dispersible granules, wettable powders, dispersible oil suspensions, and dry suspensions.

6. The herbicidal composition according to claim 5, characterized in that, The dispersible oil suspension comprises the following components by weight percentage: 10-60% active ingredient, 8-35% emulsifier, 1-5% dispersant, 1-6% thickener, and 100% dispersion medium.

7. The herbicidal composition according to claim 6, characterized in that, The effective ingredient is 20-60%; And / or, the emulsifier is 15-30%; And / or, the dispersant is 2-5%; And / or, the thickener is 2-5%.

8. The herbicidal composition according to claim 4, characterized in that, The emulsifier is selected from at least one of alkylbenzene sulfonate calcium, fatty amine polyoxyethylene ether, castor oil polyoxyethylene ether, polyoxyethylene dehydrated sorbitan monooleate, styrene-based phenol polyoxyethylene ether, and polyoxyethylene ether phosphate. And / or, the dispersant is selected from at least one of alkyl naphthalene sulfonate formaldehyde condensate, polyoxyethylene-polyoxypropylene block copolymer, calcium lignosulfonate and modified polyacrylic acid copolymer; And / or, the thickener is selected from at least one of silica, organobentonite and urea; And / or, the dispersion medium is selected from at least one of methyl oleate, castor oil, soybean oil, rapeseed oil methyl ester, and solvent oil.

9. The herbicidal composition according to claim 5, characterized in that, The preparation method of the dispersible oil suspension is as follows: After a first mixing of the dispersion medium, thickener, emulsifier, and dispersant, the active ingredient is added for a second mixing, and finally, the mixture is ground to a particle size D. 90 The dispersible oil suspension was obtained with a particle size of less than 8µm.

10. The herbicidal composition according to claim 9, characterized in that, The second mixing is carried out by shearing.

11. The herbicidal composition according to claim 10, characterized in that, The shearing conditions include: a speed of 1000-10000 r / min and a time of 10-30 min.

12. The use of the herbicidal composition according to any one of claims 1-11 in controlling annual weeds in wheat crop fields; in, The annual weed mentioned is *Alopecurus aequalis*.