Emulsifiable floating granule of weeding composition for machine-transplanted rice seedling field and preparation method of emulsifiable floating granule

Abstract

The invention discloses emulsifiable floating granules of a weeding composition for a machine-transplanted rice seedling field and a preparation method of the emulsifiable floating granules. The weeding composition comprises the following components in percentage by weight: 1-10% of pretilachlor raw medicine, 1-10% of mefenacet raw medicine, 1-10% of bispyribac-sodium raw medicine, 2-6% of a wetting agent, 4-15% of a dispersing agent, 0.5-1.5% of a binder, 1-10% of a disintegrating agent, 10-40% of adsorbent corn starch and the balance of floating beads. The composition is prepared into emulsifiable floating granules through the working procedures of dissolution, emulsification, adsorption, volatilization, extrusion granulation and the like, and the emulsifiable floating granules have the characteristics of automatic emulsification and dispersion of missible oil and the characteristic of convenience in application of water dispersible granules. In the acting period of the particles, the active ingredients of the particles are slowly desorbed in water and automatically dispersed like missible oil until the active matter concentration is uniform, additional manual uniform mixing operation is not needed, the weeding lasting period is long, the toxicity to the environment is reduced, and ecological balance development is facilitated.

Description

Technical Field

[0001] The invention belongs to the technical field of pesticides, and particularly relates to an emulsifiable floating granule of a rice machine transplanting field weed control composition and a preparation method thereof. Background Art

[0002] As an important product of modern agricultural development, especially the "10,000-acre fertile land" project, the machine-transplanted rice seedling field can not only complete the rice planting work without manual labor, saving labor costs, but also improve the efficiency of rice cultivation and avoid wasting rice seedling fields. The machine-transplanted rice seedling field is planted after the roots are turned over. The machine-transplanted rice seedlings have large row spacing and a lot of open fields, which provide strong conditions for the occurrence of weeds, especially in the early stage of rice turning green to tillering, when field weeds are more likely to occur. At present, the main weeds in the machine-transplanted rice seedling fields are barnyard grass, Leptochloa chinensis, Paspalum, Duck tongue grass, Cyperus dimorphus, etc. Relying on traditional pesticide spraying methods is time-consuming and labor-intensive.

[0003] Pretilachlor is an amide herbicide, a highly effective, low-toxic, broad-spectrum pre-emergence selective herbicide, which can be used for soil treatment to control barnyard grass, sedge, felt, duckweed, narrow-leaved alisma, etc. in paddy fields, and is usually used 3 to 5 days before transplanting. However, it has poor selectivity for wet-planted rice when applied alone.

[0004] Mefenacet is an amide herbicide and a systemic blocking herbicide. It is mainly absorbed through the bud sheath and roots and is used to control grass weeds in rice fields. It has special effects on barnyard grass and rice barnyard grass. Due to its low solubility in water, it is generally most active when applied under water-retaining conditions.

[0005] Bispyribac-sodium is a benzoic acid herbicide and a highly active acetolactate synthase (ASL) inhibitor. After being sprayed on weeds, bispyribac-sodium can be quickly absorbed by the stems and leaves of weeds. It is highly effective, broad-spectrum, and low in dosage. Bispyribac-sodium can effectively control barnyardgrass and other grass weeds in rice fields, and can also control most broad-leaved weeds, some sedge weeds, and barnyardgrass that is resistant to other herbicides.

[0006] At present, the common dosage forms of herbicides are usually emulsifiable concentrates, suspension concentrates, wettable powders, etc. For example, the original drug of pretilachlor itself is a viscous liquid with low solubility in water. The mainstream dosage forms currently registered or patented are mainly emulsifiable concentrates, which are prepared into suspension concentrates or water-dispersible granules. However, emulsifiable concentrates, wettable powders, etc. are highly polluting dosage forms, and their current registration is restricted and their volume is constantly decreasing. According to data, pretilachlor, under water-retaining conditions or prepared into conventional granules, will cause oil-water separation due to its low water solubility of the original drug itself, so the weed control effect is poor; bispyribac has a high degradation rate in water and a short duration; the above active ingredients are prepared into ordinary granules or water-dispersible granules, and the efficacy is limited. In addition, many rice varieties are sensitive to these chemical herbicides, and they will also cause herbicide damage at conventional herbicide application doses. In order to reduce the adverse effects of chemical herbicides on rice production, it is necessary to develop a herbicide with a small amount of chemical herbicides, good weed control effect, and long action time. Summary of the invention

[0007] In view of the technical problems pointed out in the background technology, the purpose of the present invention is to provide an emulsifiable floating granule of a rice machine transplanting field weed control composition and a preparation method thereof. In view of the weed control properties and application methods of pretilachlor, mefenacet and bispyribac-sodium, a rice machine transplanting field weed control composition is provided, and the composition is prepared into an emulsifiable floating granule through the processes of dissolution, emulsification, adsorption, volatilization, extrusion granulation, etc., which is convenient to apply and has significant control effect.

[0008] The invention firstly provides a weed control composition for a rice machine transplanting field, wherein the active components of the composition consist of pretilachlor, mefenacet and bispyribac-sodium, wherein the mass ratio of pretilachlor, mefenacet and bispyribac-sodium is 1-10:3.5-5:1-10; preferably, the mass ratio of pretilachlor, mefenacet and bispyribac-sodium is 5:3.5:1.5.

[0009] The present invention further provides an emulsifiable floating granule comprising the above herbicidal composition. The applicant draws on previous experience and actual efficacy tests to select 5%-20% by weight of the total active ingredient, preferably 8%-16%, more preferably 10-16%, and more preferably 10%, namely 5% of pretilachlor, 3.5% of mefenacet, and 1.5% of bispyribac-sodium.

[0010] As one of the preferred technical solutions of the above-mentioned emulsifiable floating granules containing the herbicidal composition, it includes, by weight percentage: 8%-16% of the herbicidal composition, 5%-20% of the emulsifier, 2%-6% of the wetting agent, 5%-12% of the dispersant, 0.5%-1.5% of the binder, 5% of the disintegrant, 25-35% of the adsorbent, and the balance is floating beads.

[0011] Furthermore, the emulsifiable floating granules include, by weight percentage: 10%-16% of the herbicidal composition, 10%-20% of the emulsifier, 3%-6% of the wetting agent, 8%-12% of the dispersant, 0.5%-1.5% of the binder, 5% of the disintegrant, 25-32% of the adsorbent, and the remainder is floating beads.

[0012] Furthermore, the emulsifiable floating granules include, by weight percentage: 10% of the herbicidal composition, 10% of the emulsifier, 3% of the wetting agent, 8% of the dispersant, 1% of the binder, 5% of the disintegrant, 25-32% of the adsorbent, and the balance is floating beads.

[0013] The emulsifier of the present invention is an alkyl (C 10 -C 16 ) calcium salt of benzenesulfonate, ammonium salt of alkylbenzenesulfonate, sodium salt of fatty alcohol polyoxyethylene ether sulfate, sodium salt of alkylphenol polyoxyethylene ether sulfate, sodium salt of arylphenol polyoxyethylene ether sulfate, alkyl phosphate ester salt, alkylphenol polyoxyethylene ether, fatty alcohol polyoxyethylene ether, fatty amine polyoxyethylene ether, alkylphenol polyoxyethylene ether formaldehyde condensate, alkylphenol polyoxyethylene polyoxypropylene ether, vegetable oil polyoxyethylene ether, polyoxyethylene ether fatty acid ester, ethylene oxide / propylene oxide block copolymer, sorbitan ester ether, polyglycerol fatty acid ester, etc., preferably ethylene oxide / propylene oxide block copolymer.

[0014] The wetting agent is alkylbenzene sulfonate, alkyl sulfate, polyoxyethylene-polyoxypropylene block copolymer, alkylnaphthalene sulfonate, alkyl succinate sulfonyl sodium salt, fatty amide N-methyl taurine sodium salt, fatty alcohol polyoxyethylene ether sodium sulfate, alkylphenol polyoxyethylene ether, alkylphenol polyoxyethylene ether sulfate, alkylphenol polyoxyethylene ether succinic acid half ester sulfonate, alkylphenol polyoxyethylene ether formaldehyde condensate, alkylphenol polyoxyethylene ether formaldehyde condensate sulfate, alkylphenol polyoxyethylene ether formaldehyde condensate succinic acid half ester sulfonate, lignin sulfonate, polycarboxylate, fatty alcohol polyoxyethylene ether, alkyl biphenyl ether sodium sulfonate, dimethyl octanediol, dimethyl octanediol ethylene oxide adduct, tetramethyl decanediol, tetramethyl decanediol ethylene oxide adduct, and organic phosphate; preferably alkyl sulfate.

[0015] The dispersant is polyacrylate copolymer, alkylnaphthalenesulfonic acid formaldehyde condensate sodium salt, lignin sulfonate, alkyl polyoxyethylene ether formaldehyde condensate, alkyl polyoxyethylene ether formaldehyde condensate sulfate, aralkyl polyoxyethylene ether formaldehyde condensate, aralkyl polyoxyethylene ether formaldehyde condensate sulfate, alkylnaphthalenesulfonic acid formaldehyde condensate, aralkylnaphthalenesulfonic acid formaldehyde condensate, aralkylnaphthalenesulfonic acid formaldehyde condensate, aralkylnaphthalenesulfonic acid formaldehyde condensate sodium salt, alkylphenol polyoxyethylene ether, alkylphenol polyoxyethylene ether phosphate, fatty alcohol polyoxyethylene ether, fatty alcohol polyoxyethylene ether sulfate, fatty amide N-methyl taurine sodium salt, alkylnaphthalenesulfonate, glycerol fatty acid ester polyoxyethylene ether, vegetable oil ethylene oxide adduct, vegetable oil ethylene oxide adduct derivative, and organic phosphate; considering the economic cost, alkylnaphthalenesulfonic acid formaldehyde condensate sodium salt is preferred.

[0016] The binder is sodium carboxymethyl cellulose.

[0017] The disintegrant is ammonium sulfate, sodium sulfate, soluble starch, sodium bicarbonate, urea, and sodium chloride; sodium sulfate is preferred, and the manufacturer does not make any special restrictions, and conventional ones can be used.

[0018] Based on environmental considerations, the adsorbent is corn starch, with a weight ratio of 25%-35%, preferably 25-32%.

[0019] The floating beads of the present invention have a bulk density of 0.060 g / cm 3, , floating rate ≥99.98%.

[0020] The present invention also provides a method for preparing an emulsifiable floating granule containing a herbicidal composition, which is prepared by dissolving, emulsifying, adsorbing, volatilizing, extruding and granulating, and specifically comprises the following steps: ①Dissolve the original drug of pretilachlor in the solvent, add the emulsifier and stir evenly; ②Use corn starch to absorb the pretilachlor emulsifiable concentrate solution, stirring while absorbing to make the materials mix evenly; ③ Using static or boiling drying methods, the temperature is controlled at 50-60°C, and the ethanol contained in the above-mentioned mixed material is dried, and the standard is that the solid mass does not change; ④ Mix the bispyribac-sodium technical, mefenacet technical, wetting agent, dispersant, binder, disintegrant and floating beads, and the fineness of the mixture is between 45μm and 100μm; ⑤ Grind the mixture by air flow, and the particle size is 100% <45μm; ⑥Mix the solid pretilachlor with the air flow crushed material, add 5%-20% pure water to the mixture, and knead it until it can be kneaded into a ball and falls apart when loosened; ⑦ Using a spiral extrusion granulator to extrude the mixture in step ⑥ to form tiny particles with a particle size between 0.3 and 0.5 mm; ⑧ Dry the granules at a temperature between 60 and 65° C. to remove moisture; ⑨ Screen the dried granules to obtain the desired emulsifiable floating granules.

[0021] Among them, the solvent described in step ① is used as a medium, and the criteria for the selected medium are low dosage, high solubility in pretilachlor, and easy volatility after adsorption. The intermediate solvent is selected from aromatic solvent oil, white oil, methanol, ethanol, ethylene glycol, methyl oleate, soybean oil, and N-methylpyrrolidone; ethanol is preferred.

[0022] The invention emulsifies pretilachlor and prepares emulsifiable floating granules with other two effective ingredients, so that pretilachlor contacts water in an emulsified state; it is packaged in water-soluble bags to delay the degradation of bispyribac-sodium caused by contact with water; the more direct economic benefits are saving labor and convenient operation, and the machine transplanting rice field only needs to throw the water-soluble bags at fixed points. It can be applied to the machine transplanting rice field by manual or mechanical spreading.

[0023] Compared with the prior art, the present invention has at least one of the following positive effects: 1. The present invention integrates the weed control mechanisms of pretilachlor, mefenacet and bispyribac, and uses the three active components in combination. The optimal ratio is determined through a ratio screening experiment, which significantly improves the weed control effect, can inhibit the growth of weeds at all stages, reduces the amount of active components used, and reduces the phytotoxicity of herbicides to rice. The herbicidal composition has a long weed control period, has reduced environmental toxicity, and is conducive to the development of ecological balance.

[0024] 2. In view of the physical properties of the original drug of pretilachlor, the concept of solid emulsifiable concentrate is introduced. Through the processes of dissolution, emulsification, adsorption, volatilization, extrusion granulation, etc., the composition is prepared into emulsifiable granules, which have the characteristics of automatic emulsification and dispersion of emulsifiable concentrate and the convenient application characteristics of water-dispersible granules. During the action period, the active ingredients of the granules are slowly desorbed in water and automatically dispersed like emulsifiable concentrate until the concentration of the active substance is evenly dispersed, without the need for additional manual mixing operations.

[0025] 3. The emulsifiable floating granules prepared by the present invention overcome the low solubility and fast degradation rate of pretilachlor and bispyribac-sodium in water, and increase the solubility of pretilachlor in water through the formation of emulsification, thereby achieving the technical effect of reducing dosage and increasing efficiency. DETAILED DESCRIPTION

[0026] The present invention is described below by means of specific implementation examples, but is not limited to the specific implementation examples given below.

[0027] Implementation Cases The paddy field weed control composition consists of the following components in parts by weight: 1-10% of pretilachlor as an active component, 3.5-5% of mefenacet as an active component, 1-10% of bispyribac-sodium as an active component, 5-20% of an emulsifier, 2-6% of a wetting agent, 5-12% of a dispersant, 1% of sodium carboxymethyl cellulose as a binder, 5% of sodium sulfate as a disintegrant, 25-32% of corn starch as an adsorption carrier and the remaining floating beads.

[0028] The above-mentioned active ingredients of pretilachlor, mefenacet and bispyribac-sodium are from Jiangsu Agricultural Hormone Engineering Technology Research Center Co., Ltd., and the purity meets the relevant quality requirements. The above-mentioned emulsifier is selected from the ethylene oxide / propylene oxide block copolymer Ethylan NS-500LQ from Nouryon or the sodium salt of fatty alcohol polyoxyethylene ether sulfate SoprophorFD; the above-mentioned wetting agent is the alkyl sulfate from Syensqo Additives Company's Geropon L-WET-P or the fatty amide N-methyl taurine sodium salt TENSIOFIX BCZ; the above-mentioned dispersant is the sodium salt of alkylnaphthalenesulfonic acid formaldehyde condensate from Nouryon Additives Company, with the product code Morwet D-425 or polyacrylate copolymer Agrilan 700. Corn starch is provided by Shandong Hongdou Food Co., Ltd. The floating beads are provided by Zhejiang Haiyue New Materials Co., Ltd., and its bulk density is 0.060g / cm 3, , floating rate ≥99.98%. Example 1

[0029] The paddy field weed control composition comprises, by weight percentage, 5% of pretilachlor, 3.5% of mefenacet, 1.5% of bispyribac-sodium, 10% of ethylene oxide / propylene oxide block copolymer Ethylan NS-500LQ as an emulsifier, 3% of alkyl sulfate Geropon L-WET-P as a wetting agent, 8% of alkyl naphthalenesulfonic acid formaldehyde condensate sodium salt Morwet D-425 as a dispersant, 1% of sodium carboxymethyl cellulose as a binder, 5% of sodium sulfate as a disintegrant, 25% of corn starch as an adsorption carrier, and the balance of floating beads.

[0030] The preparation method of the emulsifiable floating granules comprises the following steps: ① Dissolve 5g of pretilachlor technical drug in 10g of ethanol, add 10g of emulsifier ethylene oxide / propylene oxide block copolymer, stir evenly to obtain pretilachlor emulsifiable concentrate solution; ② Use 32g corn starch to absorb the pretilachlor emulsifiable concentrate solution, stirring while absorbing to make the materials mix evenly; ③ Using a static or boiling drying method, the temperature is controlled at 50-60° C., and the ethanol contained in the above-mentioned mixed material is dried, and the solid matter mass is no longer changed as the standard, to obtain a pretilachlor solid; ④ Mix the bispyribac-sodium technical, mefenacet technical, wetting agent, dispersant, binder, disintegrant and floating beads, and the fineness of the mixture is between 45μm and 100μm; ⑤ Grind the mixture by air flow, and the particle size is 100% <45μm; ⑥Mix the solid pretilachlor with the air flow crushed material, add 5%-20% pure water to the mixture, and knead it until it can be kneaded into a ball and falls apart when loosened; ⑦ Using a spiral extrusion granulator to extrude the mixture in step ⑥ to form tiny particles with a particle size between 0.3 and 0.5 mm; ⑧Dry the pellets at a temperature between 60-65°C to remove moisture; ⑨ Screen the dried granules to obtain the desired emulsifiable floating granules. Example 2

[0031] The paddy field weed control composition is composed of 1% of pretilachlor, 5% of mefenacet, 10% of bispyribac-sodium, 10% of ethylene oxide / propylene oxide block copolymer Ethylan NS-500LQ as an emulsifier, 3% of alkyl sulfate Geropon L-WET-P as a wetting agent, 8% of alkyl naphthalenesulfonic acid formaldehyde condensate sodium salt Morwet D-425 as a dispersant, 1% of sodium carboxymethyl cellulose as a binder, 5% of sodium sulfate as a disintegrant, 32% of corn starch as an adsorption carrier, and the balance of floating beads. The preparation method is the same as that of Example 1. Example 3

[0032] The paddy field weed control composition is composed of 10% of pretilachlor, 3.5% of mefenacet, 1% of bispyribac-sodium, 10% of ethylene oxide / propylene oxide block copolymer Ethylan NS-500LQ as an emulsifier, 3% of alkyl sulfate Geropon L-WET-P as a wetting agent, 58% of alkyl naphthalenesulfonic acid formaldehyde condensate sodium salt Morwet D-425 as a dispersant, 1% of sodium carboxymethyl cellulose as a binder, 5% of sodium sulfate as a disintegrant, 32% of corn starch as an adsorption carrier, and the remainder of floating beads. The preparation method is the same as that of Example 1. Example 4

[0033] The paddy field weed control composition is composed of 10% of pretilachlor, 3.5% of mefenacet, 1% of bispyribac-sodium, 10% of sodium salt of fatty alcohol polyoxyethylene ether sulfate ester Soprophor FD as an emulsifier, 3% of alkyl sulfate Geropon L-WET-P as a wetting agent, 8% of sodium salt of alkylnaphthalenesulfonic acid formaldehyde condensate Morwet D-425 as a dispersant, 1% of sodium carboxymethyl cellulose as a binder, 5% of sodium sulfate as a disintegrant, 25% of corn starch as an adsorption carrier, and the balance of floating beads. The preparation method is the same as that of Example 1. Example 5

[0034] The paddy field weed control composition is composed of 10% of pretilachlor, 3.5% of mefenacet, 1% of bispyribac-sodium salt, 10% of sodium salt of fatty alcohol polyoxyethylene ether sulfate ester Soprophor FD as an emulsifier, 3% of fatty amide N-methyl taurine sodium salt TENSIOFIX BCZ as a wetting agent, 8% of sodium salt of alkylnaphthalenesulfonic acid formaldehyde condensate Morwet D-425 as a dispersant, 1% of sodium carboxymethyl cellulose as a binder, 5% of sodium sulfate as a disintegrant, 32% of corn starch as an adsorption carrier, and the balance of floating beads. The preparation method is the same as that of Example 1. Example 6

[0035] The paddy field weed control composition is composed of: 5% of pretilachlor, 3.5% of mefenacet, 1.5% of bispyribac-sodium, 10% of ethylene oxide / propylene oxide block copolymer Ethylan NS-500LQ as an emulsifier, 3% of alkyl sulfate Geropon L-WET-P as a wetting agent, 8% of polyacrylate copolymer Agrilan 700 as a dispersant, 1% of sodium carboxymethyl cellulose as a binder, 5% of sodium sulfate as a disintegrant, 32% of corn starch as an adsorption carrier, and the balance of floating beads. Example 7

[0036] The paddy field weed control composition is composed of: 5% of pretilachlor, 3.5% of mefenacet, 1.5% of bispyribac-sodium, 5% of ethylene oxide / propylene oxide block copolymer Ethylan NS-500LQ as an emulsifier, 2% of alkyl sulfate Geropon L-WET-P as a wetting agent, 5% of alkyl naphthalenesulfonic acid formaldehyde condensate sodium salt Morwet D-425 as a dispersant, 1% of sodium carboxymethyl cellulose as a binder, 5% of sodium sulfate as a disintegrant, 32% of corn starch as an adsorption carrier, and the balance of floating beads. Example 8

[0037] The paddy field weed control composition is composed of: 5% of pretilachlor, 3.5% of mefenacet, 1.5% of bispyribac-sodium, 20% of ethylene oxide / propylene oxide block copolymer Ethylan NS-500LQ as an emulsifier, 6% of alkyl sulfate Geropon L-WET-P as a wetting agent, 12% of alkyl naphthalenesulfonic acid formaldehyde condensate sodium salt Morwet D-425 as a dispersant, 1% of sodium carboxymethyl cellulose as a binder, 5% of sodium sulfate as a disintegrant, 25% of corn starch as an adsorption carrier, and the balance of floating beads. Comparative Example 1

[0038] The difference between this comparative example and Example 1 is that the original drug of pretilachlor is not emulsified but directly adsorbed with corn starch, and the other steps are the same as those in Example 1.

[0039] Compare Examples 1, 4-7 and Comparative Example 1: Example 4 has poor emulsification and dispersion performance after entering water; Example 5 has slow wetting effect after entering water; Example 6 has serious heat generation during the extrusion process of the preparation, and the particles are rough, which is not suitable for large-scale production; Example 7 reduces the amount of emulsifier used, which affects the herbicide prevention effect; Example 8, the herbicide does not conform to the concept of green energy saving due to the large amount of emulsifier, wetting agent and dispersant used, and is not recommended for use; Comparative Example 1 has no emulsification effect, and the original drug of pretilachlor is easily suspended in the solution in the form of oil droplets and forms a precipitate.

[0040] Examples 1-3 and Comparative Example 1 were respectively applied to control barnyard grass in rice fields, and the application amount was set to 400 g / mu. The weed control effect of Example 1 was above 95%, the weed control effect of Example 2 was 90%, the weed control effect of Example 3 was 80%, and the weed control effect of the comparative example was above 70%.

[0041] The above-mentioned granular products were subjected to efficacy tests, with the control drugs being mefenacet-butyl, bispyribac-sodium, and pyrazosulfuron-methyl fine granules (Jiangsu Hormone Research Institute Co., Ltd.) and 69% benzylpyraclostrobin-benzothiazide wettable powder (Jiangsu Kuaida Agrochemical Co., Ltd.), and a blank control treatment was set up.

[0042] The test site was located in Longwangmiao Village, Chunhua Town, Changsha County, Hunan Province (28.18” N, 113.17” E), which is a hilly double-season rice area with more than 100 hectares of rice planted all year round. The weed species in the test field are rich, and the rice fields are mainly Echinochloa crus-galli, Leptochloa chinensis, Duck tongue grass, Herba Lysimachiae, Herba Cyperi, Cyperus dimorphus, etc. The occurrence amount is large and can represent the local weed occurrence situation. The soil fertility is uniform and the field surface is plowed and harrowed flat.

[0043] Rice variety: Nong Xiang 25 Cultivation method: machine transplanting Main weeds: barnyard grass Echinochloa crusgalli (L.) Beauv., Duck tongue grass Monochorion vaginal (Burm.f.)Presl ex Kunth, Moshangcai Lindernia procumbens (Krock.) Philcox Table 1 Experimental design:

[0044] Area of ​​the plot: 20 m 2 .

[0045] Number of replications: 3 times, completely randomized block arrangement.

[0046] The application method was broadcast, and the application rate was 480 g ai / hm 2 、600 g ai / hm 2 , 960 g ai / hm 2 .

[0047] When applying pesticides, record relevant data such as meteorological information, field management information, survey information, survey time and frequency, etc.

[0048] Methodology: According to the "Guidelines for Field Efficacy Tests of Pesticides (I)" GB / T 17980.40-2000, the control effect calculation method is as follows: Control effect (%) = ×100 (1) Where: PT—number of remaining weeds in the treatment area (or fresh weight) CK—Number of live grasses (or fresh weight) in the blank control area Experimental results: Table 2 The plant control effect of propan-benzyl-bispyribac-sodium granules on weeds in rice machine-transplanted fields (%) ——After applying the pesticide 20 d

[0049] Table 3 The plant control effect of propan-benzyl-bispyribac-sodium granules on weeds in rice machine-transplanted fields (%) ——After applying the pesticide 40 d

[0050] Table 4 Fresh weight control effect of propan-benzyl-bispyribac-sodium granules on weeds in machine-transplanted rice fields (%) ——After applying the pesticide 40 d

[0051] Compared with the control agent, 10% propanyl-benzothiazol-bispyribac-butyl granules have excellent control effects on weeds such as barnyard grass, duckweed, and moss in rice transplanting fields, and are safe for machine-transplanted indica rice, making them suitable for weed control in machine-transplanted fields.

[0052] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A weed control composition for a rice transplanting field, characterized in that: The active components are composed of pretilachlor, mefenacet and bispyribac-sodium, and the mass ratio of pretilachlor, mefenacet and bispyribac-sodium is 1-10:3.5-5:1-10.

2. The herbicidal composition for rice transplanting fields according to claim 1, characterized in that: The mass ratio of pretilachlor, mefenacet and bispyribac-sodium is 5:3.5:1.

5.

3. An emulsifiable floating granule, characterized in that: The composition comprises, by weight percentage: 8%-16% of the herbicidal composition of claim 1, 5%-20% of an emulsifier, 2%-6% of a wetting agent, 5%-12% of a dispersant, 0.5%-1.5% of a binder, 5% of a disintegrant, 25-35% of an adsorbent, and the remainder is floating beads.

4. The emulsifiable floating granules according to claim 3, characterized in that: The composition comprises, by weight percentage: 10%-16% of the herbicidal composition of claim 1, 10%-20% of an emulsifier, 3%-6% of a wetting agent, 8%-12% of a dispersant, 0.5%-1.5% of a binder, 5% of a disintegrant, 25-32% of an adsorbent, and the remainder being floating beads.

5. The emulsifiable floating granules according to claim 3, characterized in that: The emulsifier is selected from one or more of alkylbenzene sulfonate calcium salt, alkylbenzene sulfonate ammonium salt, fatty alcohol polyoxyethylene ether sulfate sodium salt, alkylphenol polyoxyethylene ether sulfate sodium salt, arylphenol polyoxyethylene ether sulfate sodium salt, alkyl phosphate ester salt, alkylphenol polyoxyethylene ether, fatty alcohol polyoxyethylene ether, fatty amine polyoxyethylene ether, alkylphenol polyoxyethylene ether formaldehyde condensate, alkylphenol polyoxyethylene polyoxypropylene ether, vegetable oil polyoxyethylene ether, polyoxyethylene ether fatty acid ester, ethylene oxide / propylene oxide block copolymer, sorbitan ester ether, and polyglycerol fatty acid ester.

6. The emulsifiable floating granules according to claim 3, characterized in that: The wetting agent is one or more of alkylbenzene sulfonate, alkyl sulfate, polyoxyethylene-polyoxypropylene block copolymer, alkylnaphthalene sulfonate, alkyl succinate sulfonyl sodium salt, fatty amide N-methyl taurine sodium salt, fatty alcohol polyoxyethylene ether sodium sulfate, alkylphenol polyoxyethylene ether, alkylphenol polyoxyethylene ether sulfate, alkylphenol polyoxyethylene ether succinic acid half ester sulfonate, alkylphenol polyoxyethylene ether formaldehyde condensate, alkylphenol polyoxyethylene ether formaldehyde condensate sulfate, alkylphenol polyoxyethylene ether formaldehyde condensate succinic acid half ester sulfonate, lignin sulfonate, polycarboxylate, fatty alcohol polyoxyethylene ether, alkyl biphenyl ether sodium sulfonate, dimethyl octanediol, dimethyl octanediol ethylene oxide adduct, tetramethyl decanediol, tetramethyl decanediol ethylene oxide adduct, and organic phosphate.

7. The emulsifiable floating granules according to claim 3, characterized in that: The dispersant is one or more of polyacrylate copolymer, alkylnaphthalenesulfonic acid formaldehyde condensate sodium salt, lignin sulfonate, alkyl polyoxyethylene ether formaldehyde condensate, alkylnaphthalenesulfonate, glycerol fatty acid ester polyoxyethylene ether, vegetable oil ethylene oxide adduct, and vegetable oil ethylene oxide adduct derivative.

8. The emulsifiable floating granules according to claim 3, characterized in that: The selected binder is sodium carboxymethyl cellulose; and / or, the disintegrant is one or more of ammonium sulfate, sodium sulfate, soluble starch, sodium bicarbonate, urea, and sodium chloride; and / or, the adsorbent is corn starch.

9. The method for preparing the emulsifiable floating granules according to any one of claims 3 to 8, characterized in that: The steps include: (1) dissolving the pretilachlor technical in a solvent, adding an emulsifier and stirring evenly to obtain a pretilachlor emulsifiable concentrate solution; adding the pretilachlor emulsifiable concentrate solution to an adsorbent, stirring and mixing evenly, and drying to a constant weight to obtain material A; (2) The bispyribac-sodium technical, mefenacet technical, wetting agent, dispersant, binder, disintegrant and floating beads are uniformly mixed, and the mixture is air flow-pulverized to control the maximum particle size to <45 μm to obtain material B; (3) Mix material A and material B, add 5-20% water to moisten them, and obtain material C; (4) Extruding and granulating material C to obtain wet granules with a particle size of 0.3-0.5 mm; (5) Drying and sieving to obtain emulsifiable floating granules.

10. The method for preparing the emulsifiable floating granules according to claim 9, characterized in that: The solvent described in step (1) is one or more of aromatic hydrocarbon solvent oil, white oil, methanol, ethanol, ethylene glycol, methyl oleate, soybean oil, and N-methylpyrrolidone.

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