A herbicidal composition containing azimsulfuron and endothall and its use

Abstract

This invention discloses a herbicidal composition containing pyrimisulfuron and quizalofop-P-ethyl and its application. The composition uses pyrimisulfuron and quizalofop-P-ethyl as the main active ingredients, with a mass ratio of (6.25-50):(150-1200). This herbicidal composition can be used in transplanted rice paddies to control grassy weeds, broadleaf weeds, and sedges. The composition has a reasonable composition, good rapid effect, and long-lasting effect, significantly improving weed control in rice paddies, broadening the weed control spectrum, effectively reducing the development of weed resistance, and decreasing the cost and frequency of application.

Description

Technical Field

[0001] This invention relates to the field of herbicide compound technology, specifically to a herbicide composition containing pyrimisulfuron and quizalofop-P-ethyl and its application. Background Technology

[0002] Protecting crops from plants that can interfere with their growth and reduce yields has long been a goal of agricultural production. One approach to achieving this goal is to develop selective herbicides that control weeds without exhibiting unacceptable phytotoxicity to the crops being protected.

[0003] With the development of chemical crop protection and the increasing prevalence of effective selective herbicides, monoculture has become common, leading to the repeated application of the same or similar herbicides to these crops. Hereditary variability exists in herbicide application within weed populations, increasing the number of weed species resistant to herbicides.

[0004] Due to the increasing demand for more effective weed control measures and reduced chemical inputs, there remains a need for effective herbicide combinations to improve weed control, broaden the spectrum of weed control, reduce the amount of herbicide used, mitigate environmental pollution, delay the development and spread of herbicide resistance in weeds, and reduce usage costs and herbicide residues. Summary of the Invention

[0005] Based on the above, the present invention provides a herbicidal composition containing pyrimisulfuron and quizalofop-P-ethyl and its application, which has significant synergistic effects, good herbicidal effect, broadened weed control spectrum, safety for rice, and positive effects on slowing down the development of weed resistance and reducing the dosage of herbicides used.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A herbicidal composition comprising pyrimisulfuron and quizalofop-P-ethyl, comprising the following components in parts by weight, wherein the weight ratio of pyrimisulfuron to quizalofop-P-ethyl is (6.25-50):(150-1200). Preferred weight ratios of pyrimisulfuron to quizalofop-P-ethyl are 6.25:150, 6.25:300, 12.5:300, 12.5:600, 25:600, 25:1200, and 50:1200.

[0008] The herbicidal composition also contains excipients available for use in pesticides, and the percentage of active ingredient is 10%-90%.

[0009] The composition is available in the form of a wettable powder, a water-dispersible granule, or a dispersible oil suspension.

[0010] The herbicidal composition is used for controlling weeds in transplanted rice paddies. Preferred weeds are grasses, broadleaf weeds, and sedges. Particularly preferred weeds are barnyard grass, Echinochloa crus-galli, Amaranth, and Cyperus difformis.

[0011] Compared with the prior art, the present invention provides a herbicidal composition containing pyrimisulfuron and quizalofop-P-ethyl, which has the following beneficial effects:

[0012] 1. The herbicidal composition provided by the present invention exhibits a significant synergistic effect within a certain ratio range. The control effect of the composition is significantly improved compared with that of single agents, which can reduce the dosage of pesticides, reduce the number of applications, reduce the cost of pesticides, and reduce the adverse impact of pesticides on the ecological environment.

[0013] 2. The herbicidal composition provided by the present invention, with the combination of two active ingredients, broadens the weed control spectrum, and can solve multiple weed problems with a single application, making up for the defects and limitations of single-agent use;

[0014] 3. The herbicidal composition provided by this invention has two active ingredients with different mechanisms of action, which can overcome the disadvantage of resistance easily generated by long-term single use, extend the service life of the herbicide, and is of great significance for the integrated management of weed resistance. Detailed Implementation

[0015] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] Example 1: Determination of the toxicity of different ratios of pyrimisulfuron and quizalofop-P-ethyl.

[0017] The tested weeds were: barnyard grass, Echinochloa crus-galli, Amaranth, and Cyperus difformis. The weed seeds were collected from rice paddies.

[0018] Test reagents: 91% (w / w) pyrazosulfuron technical grade and 97% (w / w) quizalofop-p-ethyl technical grade. Both technical grades were diluted with acetone and a 0.1% Tween 80 emulsifier aqueous solution, diluted immediately before use.

[0019] Experimental Methods: The experiments were conducted according to the "Guidelines for Indoor Bioassay Testing of Pesticides" -- NY / T1155.9-2008 and NY / T1155.7-2006. 70×70×100mm plastic seedling pots were placed in trays containing topsoil collected from non-cultivated land that had never been treated with herbicides, which had been air-dried and sieved. Water was added directly to the top of the seedling pots to maintain initial soil saturation. Plump and uniform weed seeds were selected and germinated in a 25 / 30℃ incubator (dark). Newly sprouted weed seeds were evenly placed on the soil surface, covered with a layer of fine soil, and kept sufficiently moist after sowing. The plants were then placed in a plant culture box with a temperature setting of 30℃ for light and 25℃ for darkness, and a light-dark cycle of 12:12h. Based on the respective activities and indoor testing characteristics of the two pesticides, different mixed combinations were designed based on the initial indoor tests (see Tables 1, 2, 3, and 4), for a total of 9 groups. Water containing the same emulsifier but without the pesticide was used as a blank control for indoor bioassays. HCL2000 walking sprayers were used for spraying, with a spray height of 35 cm, a walking speed of 24 cm / s, and a water consumption of 450 L / ha. The pesticide was applied once per treatment. Thinning was performed when barnyardgrass and Echinochloa crus-galli were at the 2-leaf-1-heart stage, Amaranth at the 2-true-leaf stage, and Cyperus difformis at the 2-leaf stage, maintaining 10 weeds per pot. Each treatment was replicated four times.

[0020] Survey Methods: A survey was conducted 15 days after treatment, for a total of one survey. Due to inconsistent concentration gradients in the experiment, weeds at low concentrations did not die completely; therefore, the absolute number method was used to investigate the fresh weight of the weeds. Surviving weed seedlings were cut along the soil surface with scissors, and the fresh weight of the weeds was measured using an analytical balance.

[0021] Data statistical analysis: Based on the survey statistics, the fresh weight inhibition rate was calculated using the following formula:

[0022] Fresh weight inhibition rate (%) = (Control fresh weight - Treatment fresh weight) / Treatment fresh weight × 100

[0023] The theoretical fresh weight inhibition rate (E0) for each treatment combination was calculated using the Gowing method, and the formula is as follows:

[0024] E0(%)=X+YX×Y / 100

[0025] In the formula, X is the fresh weight inhibition rate of target weeds when pyrimisulfuron is used alone at a certain dose; Y is the fresh weight inhibition rate of target weeds when quizalofop-p-ethyl is used alone at a certain dose; E0 is the theoretical value of the fresh weight inhibition rate of target weeds when pyrimisulfuron and quizalofop-p-ethyl are used in combination; and E is the measured value of the fresh weight inhibition rate of target weeds when pyrimisulfuron and quizalofop-p-ethyl are used in combination.

[0026] The combined effects of the two herbicides on weeds were evaluated. An E-E0 value greater than 10% indicated a synergistic effect, less than -10% indicated an antagonistic effect, and between -10% and 10% indicated an additive effect. The optimal ratio was determined based on actual control efficacy, herbicide characteristics, and the balance of the formulation.

[0027] Results Analysis: The experimental results in Tables 1, 2, 3, and 4 show that the herbicidal composition of this invention has excellent control effects on barnyard grass, Echinochloa crus-galli, Amaranth, and Cyperus difformis, with synergistic and additive effects among the active ingredients. When the mass ratios of pyrimisulfuron-methyl and quizalofop-p-ethyl are 6.25+150, 6.25+300, 12.5+300, 12.5+600, 25+600, 25+1200, and 50+1200, the E-E0 values ​​of the compound herbicides against barnyard grass, Echinochloa crus-galli, and Cyperus difformis are all greater than 10%, demonstrating a significant synergistic effect.

[0028] Table 1. Combined effects of pyrimisulfuron-methyl and quizalofop-p-ethyl on barnyardgrass (Gowing method)

[0029]

[0030]

[0031] Table 2. Combined effects of pyrimisulfuron-methyl and quizalofop-p-ethyl on Echinochloa crus-galli (Gowing method)

[0032]

[0033] Table 3. Combined effects of pyrimisulfuron-methyl and quizalofop-p-ethyl on amaranth (Gowing method)

[0034]

[0035] Table 4. Combined effects of pyrimisulfuron-methyl and quizalofop-p-ethyl on Cyperus difformis (Gowing method)

[0036]

[0037]

[0038] Example 231.2% Pyrimisulfuron-methyl·Clethodendron Wettable Powder

[0039] Weigh the raw materials according to the following mass percentages: 1.2% pyrimisulfuron, 30% quizalofop-p-ethyl, 4% calcium lignosulfonate, 5% sodium alkylnaphthalenesulfonate, 10% ammonium sulfate, 6% silica, and the balance of kaolin.

[0040] The above raw materials are added together in a conical mixer and mixed evenly. Then, they are pulverized by an air jet mill to make the average particle size of the material less than 5μm, thus obtaining a wettable powder of pyrimisulfuron-methyl·quizalofop-P-ethyl with a mass fraction of 31.2%.

[0041] Example 331.2% pyrimisulfuron-methyl·quizalofop-P-ethyl water-dispersible granules

[0042] Weigh the raw materials according to the following mass percentages: 1.2% pyrimisulfuron, 30% quizalofop-P-ethyl, 8% sodium dodecyl sulfate, 5% sodium naphthalenesulfonic acid formaldehyde condensate, 4% ammonium sulfate, 2% sodium carboxymethyl cellulose, 4% silica, and the balance bentonite.

[0043] The above raw materials are added together in a conical mixer and mixed evenly. After being pulverized by an air jet mill, the master powder is obtained. After being mixed with water and dispersed evenly by a homogenizing disperser, the mixture is extruded and granulated, then dried in a fluidized bed and screened to obtain a water-dispersible granule with a mass fraction of 31.2% pyrimisulfuron-methyl·quizalofop-p-ethyl.

[0044] Example 431.2% Pyrimisulfuron-methyl·Clethodendron Dispersible Oil Suspension

[0045] Weigh the raw materials according to the following percentages by weight: 1.2% pyrimisulfuron, 30% quizalofop-p-ethyl, 5% epoxidized soybean oil, 5% fatty alcohol polyoxyethylene ether phosphate, 8% silica, and methyl oleate to make up the balance.

[0046] Mix the above raw materials evenly, and process them in sequence using a high-speed shear and a grinding mill until the average particle size of the material is less than 5μm. Stop grinding to obtain a 31.2% mass fraction of pyrimisulfuron-methyl·quizalofop-P-ethyl dispersible oil suspension.

[0047] Example 4: Field efficacy determination of the combination of pyrimisulfuron and quizalofop-p-ethyl on weeds in transplanted paddy fields.

[0048] Test reagents: 31.2% methamidosulfuron-butanil wettable powder, water-dispersible granules, suspension concentrate, and control reagents prepared in Examples 2-4, including 50% methamidosulfuron-butanil emulsifiable concentrate, 33% methamidosulfuron-butanil water-dispersible granules, and a blank control group.

[0049] The experimental crop was rice, and the target weeds were annual grasses, broadleaf weeds, and sedges in rice paddies, specifically barnyard grass, Echinochloa crus-galli, Amaranth, and Cyperus difformis.

[0050] Experimental method: The herbicide was applied once 5-7 days after rice transplanting, when the weeds were at the 2-3 leaf stage. The experimental field was flat, with moderate soil fertility and a pH of 7.1. Each treatment was replicated four times, with each plot measuring 20 m². 2 There are 24 sub-districts in total, arranged in a randomized block design. The toxic soil method was used.

[0051] The weed control efficacy of each treatment was assessed 15 and 45 days after application. The survey method involved surveying four points per plot, each 0.25 m wide. 2 The formula for calculating drug efficacy is as follows:

[0052]

[0053] In the formula: CK is the number of weeds in the control area, and PT is the number of remaining weeds in the treated area.

[0054] Table 5. Field efficacy of herbicides for controlling weeds in rice paddies (%)

[0055]

[0056] Table 6. Field efficacy test results for weed control in rice paddies (% control rate per plant, 45 days).

[0057]

[0058] As can be seen from Tables 5 and 6, the herbicidal composition composed of pyrimisulfuron and quizalofop-P-ethyl has good control effects on grass weeds, broadleaf weeds, and sedge weeds. Its activity and herbicidal effect are not a simple sum of the activities of each component. Compared with existing single formulations, in addition to having a significant herbicidal effect, it also has a significant synergistic effect, with low formulation residue, meeting the safety requirements of pesticide formulations (Note: The recommended field dosage of quizalofop-P-ethyl is 1875-2250 g ai.i. / ha, and the recommended field dosage of pyrimisulfuron is 74.25-99 g ai / ha. Therefore, this invention strictly controls the dosage of both to meet the dosage requirements).

[0059] Safety investigation: The safety of each treatment on rice seedlings was visually assessed 15 and 45 days after application. The results showed that all tested pesticides were safe for rice growth, with no chlorosis, stunting, or other phytotoxic effects observed.

[0060] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. The application of a herbicidal composition in controlling weeds in transplanted rice paddies, characterized in that, The herbicidal composition uses pyrimisulfuron and quizalofop-P-ethyl as active ingredients, wherein the mass ratio of pyrimisulfuron to quizalofop-P-ethyl is 6.25:150 and 6.25:300, respectively. The dosage of pyrazosulfuron and quizalofop-P-ethyl is 10%-90% of the total mass of the herbicidal composition; The pyrimisulfuron-methyl and quizalofop-P-ethyl, along with adjuvants, are formulated into any pesticide formulation permitted by law. The dosage form is a wettable powder, a water-dispersible granule, or a dispersible oil suspension; The weeds mentioned are barnyard grass, Echinochloa crus-galli, Amaranth, and Cyperus difformis.

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