Weeding composition containing pyroxasulfone, isoxaflutole and terbuthylazine

Abstract

The invention relates to a weeding composition containing pyroxasulfone, isoxaflutole and terbuthylazine. The weight ratio of the three active ingredients is (3-6): (2-5): (20-25). The weeding composition disclosed by the invention can further comprise an agriculturally acceptable auxiliary agent and a carrier, and can be prepared into agriculturally acceptable dosage forms, preferably a dispersible oil suspending agent. The invention also relates to an application of the weeding composition for preventing and treating agricultural weeds.

Description

Technical Field

[0001] The invention relates to the field of agriculture, and in particular to a herbicide composition containing pyraclostrobin, isoxathiapiprolin and terbuthylazine, and application of the herbicide composition in preventing and controlling agricultural weeds. Background Art

[0002] Pyroxasulfone is a new type of isoxazole herbicide developed by Kumizu Chemical Co., Ltd. of Japan. It is a broad-spectrum, highly active pre-emergence soil treatment agent, mainly used to control annual grass and broad-leaved weeds. The mechanism of action of pyroxasulfone is to inhibit the synthesis of long-chain fatty acids in plants, and it is a very long-chain fatty acid synthesis inhibitor. Pyroxasulfone is suitable for a variety of crops, such as corn, wheat, soybeans, cotton, sunflowers, potatoes, peanuts, etc., and effectively controls annual grass weeds such as foxtail, barnyard grass, bluegrass, canary grass, crabgrass, sedge, goosegrass, ryegrass, and annual broad-leaved weeds such as nightshade, Amaranthus retroflexus, and Purslane.

[0003] Isoxaflutole is a HPPD (parahydroxyphenylpyruvate dioxygenase) inhibitor herbicide. It is a selective, systemic herbicide with a long lasting effect. After being absorbed by the roots and leaves of plants, it is transmitted to the entire plant through the phloem and xylem. It is mainly used in corn, sugarcane, sugar beets, fruits and vegetables, cotton, cereals and other crop fields to control a variety of annual weeds including broadleaf weeds and grass weeds.

[0004] Terbutylazine is a systemic herbicide belonging to the triazine class of compounds. It is mainly used for pre- and post-emergence weed control. Terbutylazine is absorbed by the roots, buds, stems and leaves, and then transported to the green leaves of the plant to inhibit photosynthesis, thereby achieving the effect of weed control. Terbutylazine has a wide range of applications and is mainly used in wheat, barley, corn, sorghum, soybeans, peanuts and other crop fields to control weeds such as chickweed, foxtail, crabgrass and foxtail grass.

[0005] No reports on the compounding of pyraclostrobin, isoxathiapiprolin and terbuthion have been found in the prior art. At the same time, the inventors have found that when the above composition is prepared into a high-content preparation such as an oil suspension, emulsification and dispersion are relatively difficult, the stability over time is relatively poor, and precipitation, creaming, oil separation, and even loss of fluidity are prone to occur. Summary of the invention

[0006] The inventors have found through experiments that the ternary composition of pyraclostrobin, isoxathiapiprolin and terbuthylazine has a synergistic effect in weed control.

[0007] In addition, the inventors have also found that by selecting specific pesticide adjuvants, the herbicidal composition containing sulfonepyraclostrobin, isoxathiapiprolin and terbuthion can be prepared into a high-content preparation, such as a dispersible oil suspension, which can solve the problems of emulsification, dispersibility, stability and other problems of high-content preparations.

[0008] Therefore, one aspect of the present invention relates to a herbicidal composition, wherein the active ingredients of the herbicidal composition include pyraclostrobin, isoxathiapiprolin and terbuthylazine; the weight ratio of the three active ingredients is 3-6:2-5:20-25.

[0009] In one embodiment of the present invention, the weight ratio of pyraclostrobin, isoxathiapiprolin and terbuthylazine is preferably 4-5:2-4:22-24.

[0010] In one embodiment of the present invention, the weight ratio of pyraclostrobin, isoxathiapiprolin and terbuthylazine is more preferably 4:3:23.

[0011] In one embodiment of the present invention, the composition further comprises an agriculturally acceptable adjuvant and / or a carrier to be prepared into an agriculturally acceptable dosage form.

[0012] The agriculturally acceptable formulations include wettable powders, suspensions, dispersible oil suspensions, water dispersible granules, emulsifiable concentrates, aqueous emulsions, microemulsions, etc. Dispersible oil suspensions are preferred.

[0013] In one embodiment of the present invention, the weight percentage of the active ingredient in the agriculturally acceptable formulation is 5-60%, preferably 10-50%, and more preferably 20-40%.

[0014] Another aspect of the present invention relates to the use of the herbicidal composition for controlling agricultural weeds in crop fields.

[0015] The crops include corn, wheat, sorghum, soybean, cotton, sunflower, potato, peanut, etc. Preferably, the crops are used in corn fields.

[0016] The agricultural weeds include crabgrass, foxtail grass, ryegrass, canary grass, goosegrass, chickweed, alopecuroides, and purslane. Preferably, the agricultural weeds are crabgrass and foxtail grass.

[0017] When the herbicidal composition of the present invention is prepared into a dispersible oil suspension, the components in the preparation and their weight percentages are as follows:

[0018] Sulfone metabendazole 3-6%, isoxathiapiprolin 2-5%, terbuthylazine 20-25%, dispersant 2-6%, emulsifier 23-28%, structure stabilizer 2-4%, oil-based carrier makes up 100%.

[0019] Preferably, the components in the preparation and their weight percentages are: 4-5% of pyraclostrobin, 2-4% of isoxathiapiprolin, 22-24% of terbuthylazine, 3-5% of dispersant, 24-26% of emulsifier, 2-3% of structural stabilizer, and the oil-based carrier makes up 100%.

[0020] More preferably, the components in the preparation and their weight percentages are: sulfonepyraclostrobin 4%, isoxathiapiprolin 3%, terbuthylazine 23%, dispersant 4%, emulsifier 25%, structural stabilizer 2.5%, and the oil-based carrier makes up 100%.

[0021] In the dispersible oil suspension of the present invention, the dispersant is a composite dispersant combining an oily dispersant and an aqueous dispersant. The oily dispersant is an oily dispersant of a nonionic random polymer with a low HLB value, and the oily dispersant of a nonionic random polymer with a low HLB value is preferably Atlox4914 (Caoda); the aqueous dispersant is an aqueous dispersant of a modified styrene acrylic polymer, and the aqueous dispersant of a modified styrene acrylic polymer is preferably Atlox Metasperse TM 550S (Heda). In addition, the weight ratio of the oily dispersant to the aqueous dispersant is 1.2:1 to 3:1, preferably 1.5:1 to 2:1, and more preferably 5:3.

[0022] Among them, the composite dispersant that combines the oily water-based dispersant of the non-ionic random polymer with a low HLB value and the water-based dispersant of the modified styrene acrylic polymer can significantly improve the dispersion of the active ingredients in the oil continuous phase, and through the strong adsorption of the active ingredients, avoid the flocculation of solid particles, which leads to the increase of particle size and the instability of the preparation. At the same time, it can improve the stability of the product after dilution with water, prevent the flocculation of solid particles after entering the water, and thus improve the overall stability.

[0023] In the dispersible oil suspension of the present invention, the emulsifier is a modified ethoxy fatty acid nonionic emulsifier with a high HLB value, and the modified ethoxy fatty acid nonionic emulsifier with a high HLB value is preferably EMULSON AG 18C.

[0024] The use of the above emulsifiers can solve the emulsification problem of the product without causing significant changes in the viscosity growth of the system.

[0025] In the dispersible oil suspension of the present invention, the structure stabilizer is selected from one or both of organic bentonite and white carbon black, preferably a composite structure stabilizer composed of organic bentonite and white carbon black, the weight ratio of the two being 1-2:1, preferably 1.5:1.

[0026] In the dispersible oil suspension of the present invention, the oil-based carrier is selected from one or more of methyl oleate, soybean oil and corn oil, preferably methyl oleate.

[0027] Another aspect of the present invention relates to a method for preparing the dispersible oil suspension concentrate of the present invention, which specifically comprises the following steps:

[0028] The sulfonepyraclostrobin, isoxathiapiprolin, terbuthylazine, a dispersant, an emulsifier, a structural stabilizer and an oil-based carrier are mixed and dispersed to prepare a dispersion; the dispersion is then subjected to primary sand grinding and secondary sand grinding, and then prepared into a dispersible oil suspension through blending, testing and filling. DETAILED DESCRIPTION

[0029] The present invention will be further described below in conjunction with embodiments, but the present invention is not limited thereto.

[0030] Unless otherwise specified, the percentages described in the following examples are all percentages by weight.

[0031] 1. Indoor weed test

[0032] Test target: Crabgrass (Digitariasanguinalis);

[0033] Test agents: sulfonepyraclostrobin technical, isoxathiapiprolin technical, terbuthylazine technical. When preparing the agent, first dissolve it with an appropriate amount of dimethylformamide, and then use 1% Tween 80 aqueous solution to prepare it to the required concentration.

[0034] Test method: Sow crabgrass seeds collected from the field in a plastic pot, cover with 1-2 mm of soil, and place in an enamel tray filled with water to allow the water to gradually seep in. Spray the soil 24 hours after sowing using a walking spray tower with a spray pressure of 275 kPa and a spray volume of 450 L / hm2. 2 After drying in the sun, the plants were transferred to an artificial climate chamber for cultivation. A 0.1% Tween-80 aqueous solution without the drug was used as a blank control. Each treatment was repeated 4 times. The fresh weight of the aboveground part of the plants was weighed 21 days after the soil treatment, and the fresh weight control effect was calculated.

[0035] Fresh weight prevention effect

[0036] E: fresh weight prevention effect;

[0037] C: fresh weight of aboveground part of control weeds;

[0038] T: fresh weight of aboveground part of treated weeds;

[0039] Then, the combined effect of the combination was calculated according to the Colby formula (SR Colby, Calculating Synergistic and Antagonistic Responsed of Herbicide Combinations. Weeds, 1967):

[0040] E0=X+Y-XY / 100………(1); or

[0041] E0=X+Y+Z-(XY+XZ+YZ) / 100+XYZ / 10000......(2)

[0042] X is the control effect when the active ingredient A is applied at an application rate of m, expressed as a percentage of the untreated control group;

[0043] Y is the control effect when the active component B is applied at an application rate of n, expressed as a percentage of the untreated control group;

[0044] Z is the control effect when the active ingredient C is applied at an application rate of r, expressed as a percentage of the untreated control group;

[0045] E0 is the theoretical control effect when active components A and B are applied at application rates of m and n, expressed as a percentage of the untreated control group (Formula 1); or, E0 is the theoretical control effect when active components A, B, C are applied at application rates of m, n, r, expressed as a percentage of the untreated control group (Formula 2).

[0046] If the observed value of the protective effect (actual protective effect) is higher than the theoretical value calculated by the above formula, the composition has superadditivity, that is, there is a synergistic effect.

[0047] The test results of the herbicidal composition of the present invention on barnyard grass are shown in the following Table 1.

[0048] Table 1 Determination results of the combination of sulfonepyraclostrobin, isoxathiapiprolin and terbuthylazine

[0049]

[0050]

[0051] The results in Table 1 show that the combination of sulfonepyraclostrobin, isoxathiapiprolin and terbuthylazine has a significant synergistic effect compared with the three single agents of sulfonepyraclostrobin, isoxathiapiprolin and terbuthylazine and their combinations.

[0052] 2. Screening of dispersible oil suspension formulations

[0053] The following auxiliary agents used in the following formula screening test of the present invention are as follows:

[0054] EMULSON AG 18C, modified ethoxylated fatty acid emulsifier (Lamberti);

[0055] Triton QS-44, nonylphenol polyether phosphate emulsifier (Dow);

[0056] Genapol-X060, fatty alcohol polyoxyethylene ether emulsifier (Clariant);

[0057] Atlox TM 4914, nonionic random polymer dispersant (Heda);

[0058] Atlox Metasperse TM 550S, modified styrene acrylic polymer dispersant (Heroda);

[0059] Morwet D-425, naphthalenesulfonate formaldehyde condensate dispersant (Aksu);

[0060] Dowfax D-850, EO / PO block copolymer dispersant (Dow);

[0061] Other reagents / auxiliaries used in the present invention are all commercially available.

[0062] 1. Emulsifier screening

[0063] Mix sulfonepyraclostrobin, isoxazolidinone, terbuthylazine, organic bentonite, white carbon black, methyl oleate and different emulsifiers shown in the table below, wherein the content of sulfonepyraclostrobin in the mixed solution is 4%, the content of isoxazolidinone is 3%, the content of terbuthylazine is 23%, the content of emulsifier is 25%, the content of organic bentonite is 1.5%, the content of white carbon black is 1%, and the content of methyl oleate is 100%. Then, add it to a sand mill and grind it at a speed of 2000r / min for 30min (containing 1.3 times zirconium oxide beads), and then conduct an emulsification dispersibility test. The test method is: use a pipette to draw 1ml of dispersible oil suspension, slowly drop it into a measuring cylinder filled with 99ml of standard hard water (342mg / L), stir it evenly, place it in a constant temperature water bath at 25℃ for 30min, and observe the emulsification dispersion. The results are shown in Table 2.

[0064] Table 2 Emulsifier screening

[0065]

[0066] The results show that EMULSON AG 18C is suitable for use as an emulsifier for the dispersible oil suspension concentrate of the present invention and is preferred in the present invention.

[0067] 2. Dispersant screening

[0068] Mix 4% pyraclostrobin, 3% isoxathiapiprolin, 23% terbuthylazine, 25% EMULSON AG 18C emulsifier, 1.5% organic bentonite, 1% white carbon black, the dispersant shown in the table below, and the balance of methyl oleate. Then, add it to a sand mill and grind it at a speed of 2000r / min for 30min (containing 1.3 times zirconium oxide beads). Then perform a suspension rate test.

[0069] The method for determining the suspension rate is as follows (refer to GB / T 14825-2006): Take 1 mL of the above-mentioned dispersible oil suspension sample, add it to a beaker containing 50 mL of standard hard water (342 mg / L), stir it evenly with a glass rod, then wash it all into a 250 mL measuring cylinder with standard hard water, and dilute it to the scale, cover it with a stopper, and use the bottom of the measuring cylinder as the axis to turn the measuring cylinder upside down 30 times within 1 minute. Open the stopper, place it vertically in a constant temperature water bath at 30°C, and leave it for 30 minutes. Then use a pipette to remove 9 / 10 (225 mL) of the contents. When drawing liquid, the pipette moves down along the inner wall of the measuring cylinder as the liquid level drops to avoid stirring the lower sediment. Determine the content of the active ingredient in the sample and the 25 mL emulsion remaining at the bottom of the measuring cylinder. The experiment is repeated 3 times. Calculate the sample suspension rate according to the following formula:

[0070] Suspension rate = [(m1-m2) / m1]×(10 / 9)

[0071] Where:

[0072] m1 represents the mass of the active ingredient in the suspension emulsion sample;

[0073] m2 represents the mass of the active ingredient in the 25 mL of suspension remaining at the bottom of the measuring cylinder.

[0074] The results are shown in Table 3 below.

[0075] Table 3 Dispersant screening

[0076]

[0077] The results in Table 3 show that Atlox TM 4914、Atlox Metasperse TM When 550S is used as a dispersant, the suspension rate is higher, which is more preferred in the invention. Therefore, the two are combined and screened to select the best ratio of the two.

[0078] According to the ratio shown in Table 4 below, the dispersant Atlox TM 4914 and Atlox Metasperse TMThe proportion of 550S was screened, and the total amount of dispersant was 4%. The suspension rate index was tested, and the heat storage stability was determined after storage at 54°C for 14 days, referring to GB / T19136-2003. The results are shown in Table 4 below.

[0079] Table 4 Dispersant screening

[0080]

[0081]

[0082] The results showed that when Atlox TM 4914 and Atlox Metasperse TM When the ratio of 550S is in the range of 1:1 to 3:1, the suspension rate and heat storage stability of the preparation are good; further, when the ratio of the two is in the range of 3:2 to 2:1, the suspension rate of the preparation is greater than 95%, and there is no oil absorption and no bottoming after hot storage; further, when the ratio of the two is 5:3, all indicators are optimal.

[0083] After formula screening, it was determined that the preferred emulsifier in the dispersible oil suspension of the present application is EMULSON AG18C; the preferred dispersant is Atlox TM 4914 and Atlox Metasperse TM The preferred dispersible oil suspension formulation of the present application is: 4% sulfonepyraclostrobin, 3% isoxathiapiprolin, 23% terbuthylazine, 2.5% Atlox TM 4914 dispersant, 1.5% Atlox Metasperse TM 550S dispersant, 25% EMULSON AG 18C emulsifier, 1.5% organic bentonite, 1% white carbon black, and methyl oleate to make up 100%.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A herbicidal composition, characterized in that: The active ingredients of the herbicidal composition include pyraclostrobin, isoxathiapiprolin and terbuthylazine; the weight ratio of the three active ingredients is 3-6:2-5:20-25.

2. The herbicidal composition according to claim 1, characterized in that The weight ratio of sulfonepyraclostrobin, isoxathiapiprolin and terbuthylazine is preferably 4-5:2-4:22-24.

3. The composition according to claim 1 or 2, characterized in that The composition further comprises an agriculturally acceptable adjuvant and / or a carrier and is prepared into an agriculturally acceptable dosage form.

4. The composition according to claim 3, characterized in that The pesticide composition is prepared into wettable powder, suspension, dispersible oil suspension, water-dispersible granule, emulsifiable concentrate, water emulsion and microemulsion.

5. A dispersible oil suspension containing pyraclostrobin, isoxathiapiprolin and terbuthylazine, characterized in that: It includes the following components and their weight percentages: Sulfone metabendazole 3-6%, isoxathiapiprolin 2-5%, terbuthylazine 20-25%, dispersant 2-6%, emulsifier 23-28%, structure stabilizer 2-4%, oil-based carrier makes up 100%.

6. The dispersible oil suspension according to claim 5, characterized in that The dispersant is a composite dispersant combining an oily dispersant and an aqueous dispersant; The oily dispersant is a nonionic random polymer Atlox4914 with a low HLB value; The aqueous dispersant is a modified styrene acrylic polymer Atlox Metasperse TM 550S; The weight ratio of the oily dispersant to the aqueous dispersant is 1.2:1 to 3:

1.

7. The dispersible oil suspension according to claim 6, characterized in that The weight ratio of the oily dispersant to the aqueous dispersant is preferably 1.5:1 to 2:1, more preferably 5:

3.

8. The dispersible oil suspension according to any one of claims 5 to 7, characterized in that The emulsifier is a modified ethoxy fatty acid nonionic emulsifier with a high HLB value, and the modified ethoxy fatty acid nonionic emulsifier with a high HLB value is EMULSON AG 18C.

9. The dispersible oil suspension according to any one of claims 5 to 8, characterized in that The structural stabilizer is selected from one or both of organic bentonite and white carbon black; preferably, it is a composite structural stabilizer composed of organic bentonite and white carbon black, and the weight ratio of the two is 1-2:1, preferably 1.5:

1.

10. Use of the herbicidal composition according to any one of claims 1 to 4 or the dispersible oil suspension according to any one of claims 5 to 9 for controlling agricultural weeds.

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