A ternary weeding composition for rice field and application thereof

Abstract

The application discloses a ternary weeding composition for rice field and application thereof, wherein the effective components of the ternary weeding composition for rice field include propanil, dichloro-isoxadifen-ethyl and flupicolide, and the weight ratio of the three effective components is 30-40:2-10:0.2-1. The application also discloses application of the weeding composition in preventing and removing weeds in the rice field. After the three components are compounded, the ternary weeding composition has obvious synergistic effect on gramineous weeds, broadleaf weeds and sedge weeds in the rice field, and can greatly reduce the amount of weeding agent, expand the weed killing spectrum and prolong the weeding effective period. The ternary weeding composition can be prepared into pesticide preparations such as dispersible oil suspending agent and water dispersible granule, and is suitable for post-emergence stem and leaf treatment of weeds in direct seeding rice field and transplanted rice field.

Description

Technical Field

[0001] This invention relates to the field of pesticide technology, specifically to a ternary herbicidal composition for paddy fields and its application. Background Technology

[0002] Rice is a major crop in my country, and there are more than 100 species of weeds in paddy fields, affecting an area of ​​20 million hectares annually. These weeds are characterized by a year-on-year increase in affected area, accelerated weed population succession, and the rapid development of resistant weeds. Currently, rice cultivation methods include direct seeding, dry direct seeding, transplanting, machine transplanting, and dryland rice cultivation. With the development of intensive and large-scale land use, lightweight cultivation methods, represented by machine transplanting and machine direct seeding, are developing rapidly. In direct seeding fields, weeds coexist with rice for a long time; weeds generally germinate before rice seeds and grow synchronously with the rice. Furthermore, the use of alternating wet and dry water management in the early post-sowing period is highly conducive to weed growth, resulting in a complex weed composition. In direct-seeded rice paddies, the first peak of weed emergence typically occurs 5-7 days after rice sowing, dominated by grasses such as barnyard grass and goosegrass; the second peak occurs 15-20 days after sowing, dominated by annual sedges and broadleaf weeds; and in some fields, a third peak occurs 20-30 days after sowing, dominated by perennial sedges and some broadleaf weeds.

[0003] Chemical weeding is the most economical and effective means of controlling weeds in paddy fields. However, continuous, long-term, and high-dose use of single-variety or single-mode chemical herbicides can lead to problems such as herbicide resistance and the evolution of resistance in weeds. In addition, paddy fields have a complex weed community, with various weeds such as grasses, broadleaf weeds, and sedges growing together. Single-variety herbicides cannot completely solve the shortcomings of weed control in paddy fields.

[0004] Propranolol is a highly selective contact amide herbicide that is almost not translocated within the weed; it only acts at the point of contact. Its mechanism of action is multifaceted, disrupting not only photosynthesis but also respiration and oxidative phosphorylation, interfering with nucleic acid and protein synthesis. This impacts the physiological functions of sensitive plants, accelerating water loss, causing leaves to gradually wither, and ultimately leading to death. In rice, propranolol is rapidly broken down into non-toxic substances by arylamidinases, making it relatively safe for rice. Barnyard grass, lacking this detoxification mechanism, suffers cell membrane damage first, leading to water metabolism disorders and rapid dehydration and death; the two-leaf stage barnyard grass is the most sensitive. However, propargite has significant shortcomings in field applications: First, as a contact herbicide, propargite is almost not translocated within the plant, meaning it cannot reach the roots of weeds, resulting in poor control of perennial and lignified older weeds; second, propargite has a short residual period and no soil-sealing effect, making it easy for newly sprouted weeds to regrow after application; third, propargite decomposes and becomes ineffective in the soil, failing to maintain its activity and thus unsuitable for soil-sealing treatment; fourth, propargite should be avoided during high temperatures, and the concentration of the herbicide solution should not be too high, otherwise it may cause phytotoxicity to rice.

[0005] Dichloroisoxane is an isoxazoline herbicide developed by FMC Corporation. It is a selective pre-emergence treatment agent widely used in rice, wheat, barley, corn, and other crop fields to control grassy weeds, broadleaf weeds, and sedges. This herbicide is absorbed through roots and young shoots and translocated upwards to all parts of the plant via transpiration. It inhibits the activity of 1-deoxy-D-xyulose-5-phosphate synthase (DXS), thereby disrupting the biosynthesis of plastid isoprene, i.e., carotenoids. When carotenoids lose their protective function, the plant's leaves turn white. Sensitive weeds cannot metabolize dichloroisoxane and ultimately die from photosynthesis. Dichloroisoxane has a broad spectrum of weed control, is effective against important resistant weeds, and also has some control effect on late-emerging weeds, with a residual effect lasting up to 12 weeks. However, dichlorvos has the following drawbacks: First, this agent is mainly absorbed through roots and young shoots, and is translocated upwards through the xylem, but not downwards or between leaves. It has poor control efficacy against older weeds that have already emerged, and is more suitable for soil-based pretreatment than foliar application. Second, the efficacy of this agent against some grass weeds, such as older barnyardgrass, needs to be improved. Third, when used as a pre-emergence pretreatment agent, it needs to be applied before the weeds germinate, resulting in a narrow application window.

[0006] Fluroxypyridine is the second arylpyridine carboxylate herbicide developed by Dow AgroSciences, following fluroxypyridine. Fluroxypyridine is absorbed through the leaves and roots of plants, exhibiting systemic activity. It is translocated through the xylem and phloem and accumulates in the meristematic tissues of weeds, thereby exerting its herbicidal activity. Fluroxypyridine is broad-spectrum, highly effective, fast-acting, and requires low dosage. It is applied post-emergence as a foliar treatment and is used in multiple crops, including rice, and in multiple regions to control grassy weeds, broadleaf weeds, and sedges. Fluroxypyridine acts on two of the most important target sites of hormone-based herbicides—TIR1 and AFB5—and has a unique binding mode with its receptors, especially a tight binding to AFB5, resulting in a significantly lower dosage compared to other hormone-based herbicides. Due to its novel mechanism of action, chlorpyrifos can address known resistance issues, including resistance to acetyl-lactate synthase (ALS) inhibitors, acetyl-CoA carboxylase (ACCase) inhibitors, p-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitors, as well as to weeds resistant to propargite, quinclorac, glyphosate, and triazine herbicides. However, chlorpyrifos also has application drawbacks: First, it has a strong inhibitory effect on young-leaf rice, and application is recommended after the 4.5-leaf stage, limiting the application window; second, as a hormone-type herbicide, application under high-temperature conditions may pose a risk of phytotoxicity to rice; third, its efficacy against some grassy weeds, such as Echinochloa crus-galli, when used as a single agent needs further improvement; and fourth, its relatively high price makes its use alone costly.

[0007] In the prior art, ternary compound compositions of propargite and chlorpyrifos have been reported, such as application number CN202411395979.7, which involves a ternary compound of propargite, butachlor, and chlorpyrifos. However, this composition contains butachlor, and since the pesticide category is the same as propargite (an amide class), the potential for synergistic effects is limited. Application number CN202311582004.0 also discloses a ternary compound of propargite, oxadiazon, and chlorpyrifos. Application number CN202411249151.0 has also reported a binary compound composition of dichloroisoxane and chlorpyrifos, which is mainly used to control euphratica. Application number CN121264478A also discloses a ternary compound composition of propargite with dichloroisoxane and cyhalofop-butyl. However, none of the above-mentioned compound formulations simultaneously address the problems of propanil's lack of contact action, lack of pre-emergence effect, and poor efficacy against older weeds; diclofenac's primarily pre-emergence effect and poor efficacy against emerging weeds; and chlorpyrifos's limited application window and high cost per agent. Currently, there are no patent reports on ternary compound formulations of propanil, diclofenac, and chlorpyrifos.

[0008] Therefore, developing a ternary herbicidal composition containing propargite, dichlorvos, and chlorpyrifos, utilizing their different mechanisms of action, complementary weed-killing spectrum, and synergistic effects to achieve a three-in-one weeding effect of "contact, pre-emergence, and systemic translocation," is of great practical significance and has broad market application prospects for solving the problem of controlling complex weeds in paddy fields, delaying the development of weed resistance, and reducing the amount and number of applications of herbicides. Summary of the Invention

[0009] The present invention aims to provide a ternary herbicidal composition for paddy fields and its application, in order to solve the problems of existing single herbicides or binary compound agents, such as narrow spectrum of weed control, single mode of action, poor control efficacy against old weeds, short duration of weed control, limited application window and easy development of herbicide resistance.

[0010] To achieve the above objectives, the present invention provides the following technical solution: A ternary herbicide composition for paddy fields, wherein the active ingredients are composed of a ternary compound of propargite, dichlorvos, and chlorpyrifos, with the weight ratio of the three active ingredients being 30-40: 2-10: 0.2-1.

[0011] Preferably, the weight ratio of the dichlorvos, dichloroisoxane and chlorpyrifos is 32-36:4-8:0.4-0.8.

[0012] More preferably, the weight ratio of the dichlorvos, dichlorvos and chlorpyrifos is 34.5:5:0.5.

[0013] Preferably, the herbicidal composition further contains agriculturally acceptable adjuvants and / or carriers, and is formulated into a dosage form selected from dispersible oil suspensions and water-dispersible granules.

[0014] Preferably, in the herbicidal composition, the total weight percentage of the three active ingredients—propargyl, dichlorvos, and chlorpyrifos—is 20% to 80%, with the remainder being agriculturally acceptable adjuvants and / or carriers.

[0015] Preferably, the herbicidal composition can be prepared into a formulation suitable for agricultural use according to conventional methods in the art, including but not limited to dispersible oil suspensions and water-dispersible granules.

[0016] Preferably, the agriculturally acceptable adjuvant and / or carrier is selected from one or more of emulsifiers, dispersants, wetting agents, antifreeze agents, thickeners, defoamers, solvents, and fillers, depending on the selected formulation.

[0017] The present invention also provides the application of the above-mentioned ternary herbicidal composition for paddy fields in the control of weeds in paddy fields.

[0018] Preferably, the application is to apply the herbicidal composition to the stems and leaves of weeds or to the soil surface in paddy fields.

[0019] Preferably, when performing post-emergence foliar treatment, the application is carried out in direct-seeded rice fields or transplanted rice fields, and the application period is after the rice has two leaves and one heart stage and the weeds have two to four leaves. When performing soil sealing treatment, the application is carried out in direct-seeded rice fields before seedling emergence or in transplanted rice fields during the greening-up period after transplanting.

[0020] Preferably, the paddy field includes direct-seeded paddy fields and transplanted paddy fields; the weeds are grass weeds, broadleaf weeds and sedge weeds in paddy fields, including but not limited to barnyard grass, barnyard grass, crabgrass, water sedge, sedge, duckweed, styrax, knotweed, styrax ...

[0021] The present invention provides a ternary herbicidal composition for paddy fields and its application, which has the following advantages: The ternary herbicidal composition provided by this invention has a significant synergistic effect and its control efficacy is better than that of single agents or any two-element combination; The ternary herbicidal composition provided by this invention can prolong the herbicidal effect and reduce the number of applications. The ternary herbicidal composition provided by this invention can greatly reduce the dosage and lower the cost of herbicides. Detailed Implementation

[0022] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. 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. In the following embodiments and comparative examples, unless otherwise stated, all percentages are weight percentages.

[0023] Example 1: 40% propargite·dichloroisoxane·chloropyridinium dispersible oil suspension This embodiment provides a ternary herbicidal composition for paddy fields and its preparation method: The formulation of the ternary herbicidal composition is as follows (by weight percentage): 34.5 wt% propargite, 5 wt% dichloroisoxane, 0.5 wt% chlorofluoropyridine ester, 8 wt% triethanolamine dodecylbenzenesulfonate (Nantong Deyi Chemical Co., Ltd.), 4 wt% castor oil polyoxyethylene ether (Emulsogen EL360, Clariant Chemicals (China) Co., Ltd.), 4 wt% EO / PO block polyether (Ethylan NS-500LQ, Norinone Chemical Co., Ltd.), 20 wt% isophorone, 20 wt% N-methylpyrrolidone, 0.5 wt% organobentonite, and the balance of solvent oil S200.

[0024] Its preparation method is as follows: Isophorone, N-methylpyrrolidone, solvent oil S200, triethanolamine dodecylbenzenesulfonate, organobentonite, Emulsogen EL360, Ethylan NS-500LQ, propargite, dichloroisoxane, and chloropyridine ester were sequentially added to a shearing vessel and sheared evenly. The mixture was then ground in a sand mill until the median particle size D50 ≤ 5 μm, resulting in a ternary composition dispersible oil suspension, labeled as 40% propargite·dichloroisoxane·chloropyridine ester dispersible oil suspension.

[0025] Example 2: 80% propargite·dichloroisoxane·chloropyridinium chloride water-dispersible granules The formulation of the ternary herbicidal composition is as follows (by weight percentage): 69 wt% propargite, 10 wt% dichloroisoxane, 1 wt% chlorofluoropyridine ester, 2 wt% alkyl naphthalene sulfonate Morwet EFW (Nouryon Chemicals Ltd.), 8 wt% alkyl naphthalene sulfonate Morwet D425 (Nouryon Chemicals Ltd.), 4 wt% polycarboxylate dispersant Sokalan CP5 (BASF AG), 4 wt% silica, and the balance being kaolin.

[0026] Its preparation method is as follows: Add propargite, dichloroisoxane, chloropyridine ester, silica, Morwet EFW, Morwet D425, and Sokalan CP5 sequentially to a high-speed mixing vessel and mix thoroughly. Then add 10% water and knead until uniform. Transfer the kneaded material to a rotary granulator, select a 2mm sieve, and extrude to granulate. Transfer the granules to a fluidized bed dryer and dry them at 60℃ until the moisture content is ≤2%, thus obtaining the water-dispersible granules of the ternary composition, labeled as 80% propargite·dichloroisoxane·chloropyridine ester water-dispersible granules.

[0027] Example 3: 20% Dichloroisocyanurate·Isoxafen·Clonopyridine dispersible oil suspension The formulation of the ternary herbicidal composition is as follows (by weight percentage): 17.25 wt% propargite, 2.5 wt% dichloroisoxane, 0.25 wt% chlorofluoropyridine ester, 9% calcium dodecylbenzenesulfonate 505W (Nantong Deyi Chemical Co., Ltd.), 6 wt% tristyrene-phenylphenol polyoxyethylene ether emulsifiable concentrate 602 (Nantong Deyi Chemical Co., Ltd.), 1% organobentonite 838F, and the balance being methyl oleate.

[0028] The preparation method is the same as in Example 1.

[0029] Combined effect test The combined effect of the ternary herbicidal composition described in Example 1 on barnyard grass, water sedge, and clove knotweed was determined.

[0030] Weed testing: Collect mature barnyard grass, water sedge, and clove knotweed seeds, remove impurities, and store them in the laboratory for later use.

[0031] Experimental Methods: Sifted fine soil was placed in perforated plastic basins (10cm in diameter), and watered thoroughly using bottom irrigation. Barnyard grass seeds were soaked for 24 hours and then evenly sown on the soil surface, 30 seeds per basin. The basins were then covered with 1cm of fine soil, and watered again using bottom irrigation until the soil was moist. Following the "Guidelines for Indoor Bioassay Testing of Pesticides," a foliar spray treatment was used. The pesticide was applied when the weeds had two leaves and one heart leaf, at a spray volume of 40mL / m², with one application. The control efficacy against barnyard grass was assessed 28 days after application.

[0032] This experiment used the Colby method to test the activity of the three herbicides mixed together. The formula for calculating the mixing ratio is as follows: E0(%)=X*Y*Z / 100 (n-1) In the formula: X represents the measured weed survival rate of propargite; Y represents the measured weed survival rate of dichlorvos; Z represents the measured weed survival rate of chlorpyrifos; n represents the amount of compound herbicide; E0 represents the theoretical survival rate of the mixture; E represents the measured survival rate; fresh weight efficacy (%) = (1 - fresh weight of weeds in the treatment area / fresh weight of weeds in the control area) * 100%. Survival rate (%) = 1 - fresh weight efficacy (%) When E-E0 < -10%, it indicates a synergistic effect; when E-E0 > 10%, it indicates an antagonistic effect; when E-E0 is between ±10%, it indicates that the mixed ternary herbicidal composition has an additive effect.

[0033] Table 1. Determination of the combined effect of the ternary herbicidal combination of propargite, dichlorvos, and chlorpyrifos against barnyardgrass. Table 1 shows that the ternary combination of propargite, dichlorvos, and chlorpyrifos exhibits excellent control efficacy against barnyardgrass. The measured fresh weight control efficacy ranged from 84% to 100%, with 17 treatments showing efficacy ≥90%. Based on the Colby method, no antagonistic effects were observed in any of the combinations. Five treatments (517.5+75+7.5, 776.25+75+7.5, 776.25+112.5+7.5, 1035+75+7.5, 1035+150+7.5) showed synergistic effects, with E-E0 values ​​ranging from -11.15 to -10.36; the remaining treatments showed additive effects. In the synergistic combinations, chlorpyrifos was used at a low dose (7.5 g ai / hm). 2 This indicates that the ternary ratio can significantly enhance the combined toxicity to barnyardgrass while reducing the dosage of chloropyridinium ester, demonstrating potential for synergistic effects.

[0034] Table 2. Determination of the combined effect of the ternary herbicidal combination of propanil, dichloroisoxane, and chlorpyrifos against Cyperus rotundus. Table 2 shows that the ternary combination of propargite, dichlorvos, and chlorpyrifos exhibits excellent control efficacy against Cyperus rotundus, with measured fresh weight control efficacy ranging from 86% to 100%, and 21 treatments showing efficacy ≥90%. Based on the Colby method, no antagonistic effects were observed in any combination. Among the 27 treatments, 22 combinations showed synergistic effects (E-E0 values ​​between -18.83 and -10.34), while the remaining 5 showed additive effects. Synergistic effects were prevalent across all dosage ratios, especially when the propargite dosage was 1035 g ai / hm. 2 At the time, all nine combinations showed synergistic effects, with control efficacy reaching 97%–100%. In addition, dosage changes of dichlorvos and chlorpyrifos had little impact on the degree of synergistic effect, indicating that the ternary combination has stable and highly effective synergistic effects in controlling water sedge.

[0035] Table 3. Determination of the combined effect of the ternary herbicidal combination of propargite, dichlorvos, and chlorpyrifos on styrax. Table 3 shows that the ternary combination of propargite, diclofenac, and chlorpyrifos exhibits excellent control efficacy against Polygonum hydropiper, with measured fresh weight control efficacy ranging from 88% to 100%, and 17 treatments showing efficacy ≥95%. Based on the Colby method, no antagonistic effect was observed in any combination; among the 27 treatments, 24 combinations showed synergistic effects (E-E0 values ​​between -14.46 and -10.02), while only 3 treatments (776.25+150+15, 776.25+150+11.25, and 1035+150+15) showed additive effects. Synergistic effects were widespread across all dosage ratios, especially when the propargite dosage was 517.5 or 776.25 g a.i. / hm.2 At that time, all combinations showed synergistic effects. Notably, the clopyridostilbene dosage increased from 7.5 to 15 g ai / hm. 2 Furthermore, the control efficacy was further enhanced, and most treatments maintained their synergistic effect. In summary, this ternary combination exhibits stable and highly efficient synergistic effects on Polygonum syringae.

[0036] Field efficacy and safety trials Test reagent: 40% propargite·dichloroisoxane·chloropyridinium dispersible oil suspension of Example 1.

[0037] Test date: July 24, 2024 Test location: Qu Yuan Management District, Miluo City, Hunan Province Planting method: Direct seeding of rice Field weeds: barnyard grass, Echinochloa crus-galli, Crataegus pinnatifida, Cyperus difformis, Cyperus difformis, Eclipta prostrata, Chamaedorea javanica, Polygonum hydropiper, Amaranthus auricula-judae, and Cyperus rotundus, etc.

[0038] Application Technique: After the land has been prepared and dried, evenly sow the sprouted rice grains. Apply the pesticide the day after rice sowing according to the following plan. Each treatment covers 100m². 2 Set up three repeats. Use electric sprayers to ensure no double spraying and no missed spraying.

[0039] Survey method: Four points were randomly selected from each community, and each point was surveyed over a distance of 0.25m. 2 The fresh weight of aboveground weeds was investigated 28 days after application of the pesticide. The results are shown in the table below.

[0040] The formula for calculating the total control efficacy by number of plants is: control efficacy by fresh weight (%) = (1 - fresh weight of weeds in the treatment area / fresh weight of weeds in the control area) * 100%.

[0041] Table 4. Field efficacy and safety results 7 days after application. The 40% propargite·dichloroisoxane·chlorpyrifos-dispersible oil suspension described in Example 1 is safe for rice when applied at a dosage of 100g / mu. Seven days after application, the control efficacy against barnyard grass is 99%, against water sedge is 96%, against syringa vulgaris is 94%, and the total control efficacy is 95%.

[0042] The 40% propargite·dichloroisoxane·chlorpyrifos-dispersible oil suspension described in Example 1 is safe for rice when applied at a dosage of 150g / mu. Seven days after application, the control efficacy against barnyard grass is 100%, against water sedge is 97%, against syringa vulgaris is 97%, and the overall control efficacy is 98%.

[0043] The 40% propargite·dichloroisoxane·chlorpyrifos-dispersible oil suspension concentrate described in Example 1 is safe for rice when applied at a dosage of 200g / mu. Seven days after application, it showed 100% control efficacy against barnyard grass, 100% control efficacy against water sedge, 100% control efficacy against syringa vulgaris, and a total control efficacy of 100%.

[0044] When using a single component such as 34% propargite EC, 36% dichlorvos SC, 3% chlorpyrifos EC, or any combination of two components, even at amounts far exceeding the dosage of the same active ingredient in the 40% propargite·dichlorvos·chlorpyrifos SC dispersible oil suspension of Example 1, the control efficacy still cannot reach the control effect of the 40% propargite·dichlorvos·chlorpyrifos SC dispersible oil suspension of Example 1. Furthermore, when the dosage of propargite and chlorpyrifos increases, phytotoxic symptoms such as herbicide spots or stunted plants may appear.

[0045] When commercially available 34% propargite EC, 36% dichlorvos SC, and 3% chlorpyrifos EC are used in combination, the overall control efficacy can reach 90%, which is still somewhat lower than that of Example 1 of this invention. This is because the efficacy of a product depends not only on the active ingredient and dosage, but also significantly on the stability of the diluted emulsion. Mixing the three products may result in poor emulsion stability, leading to oil floating or sedimentation, thus affecting the efficacy of the active ingredient and consequently the control effect. Furthermore, under field conditions, due to the early sealing effect of dichlorvos and the synergistic effect of adjuvants, the actual control efficacy is higher than that in indoor pot experiments.

[0046] Table 5. Field efficacy and safety results 14 days after application. Table 5 shows that the 40% propargite·dichloroisoxane·chlorpyrifos dispersible oil suspension concentrate described in Example 1 is safe for rice at an application dose of 100g / mu. 14 days after application, the control efficacy against barnyard grass is 96%, against water sedge is 95%, against syringa vulgaris is 92%, and the total control efficacy is 94%.

[0047] The 40% propargite·dichloroisoxane·chlorpyrifos-dispersible oil suspension concentrate described in Example 1 is safe for rice when applied at a dosage of 150g / mu. 14 days after application, the control efficacy against barnyard grass is 98%, against water sedge is 96%, against syringa vulgaris is 93%, and the total control efficacy is 97%.

[0048] The 40% propargite·dichloroisoxane·chlorpyrifos-dispersible oil suspension concentrate described in Example 1 is safe for rice when applied at a dosage of 200g / mu. 14 days after application, the control efficacy against barnyard grass is 100%, against water sedge is 99%, and against syringa is 97%, with a total control efficacy of 99%.

[0049] The efficacy of commercially available single-agent pesticides further decreased 14 days after application. This is because propargite, being a contact pesticide, lacks systemic activity. When control is incomplete, weed rebound is unavoidable. Although chlorpyrifos has systemic activity, its control efficacy will also be affected by the increase in weed resistance.

[0050] The safety of each treatment on rice shows that 14 days after application, no obvious symptoms of pesticide damage were observed in the growth of any of the rice varieties.

[0051] Table 6. Field efficacy and safety results 28 days after application. The 40% propargite·dichloroisoxane·chlorpyrifos-dispersible oil suspension concentrate described in Example 1 is safe for rice at an application rate of 100g / mu. 28 days after application, it showed an efficacy of 87% against barnyard grass, 82% against water sedge, and 79% against syringa vulgaris, with a total efficacy of 84%.

[0052] The 40% propargite·dichloroisoxane·chlorpyrifos-dispersible oil suspension concentrate described in Example 1 is safe for rice when applied at a dosage of 150g / mu. 28 days after application, it showed a control efficacy of 93% against barnyard grass, 90% against water sedge, and 85% against syringa vulgaris, with a total control efficacy of 91%.

[0053] The 40% propargite·dichloroisoxane·chlorpyrifos-dispersible oil suspension concentrate described in Example 1 is safe for rice when applied at a dosage of 200g / mu. 28 days after application, it showed a control efficacy of 96% against barnyard grass, 92% against water sedge, and 87% against syringa vulgaris, with a total control efficacy of 95%.

[0054] The efficacy of each single agent was further reduced, while the 40% propargite·dichloroisoxane·chloropyridinium dispersible oil suspension of Example 1 of the present invention still had good efficacy.

[0055] The embodiments have provided a detailed description of the present invention; however, modifications or improvements can be made to it, as will be apparent to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A ternary herbicidal composition for paddy fields, characterized in that, The herbicidal active ingredients of the herbicidal composition consist of propargite, dichlorvos, and chlorpyrifos, with a weight ratio of 30-40:2-10:0.2-1.

2. The ternary herbicidal composition for paddy fields according to claim 1, characterized in that, The weight ratio of the chlorpyrifos, dichlorvos, and chlorpyrifos is 32–36: 4–8: 0.4–0.

8.

3. The ternary herbicidal composition for paddy fields according to claim 1, characterized in that, The weight ratio of the dichlorvos, dichlorvos, and chlorpyrifos is 34.5:5:0.

5.

4. The ternary herbicidal composition for paddy fields according to any one of claims 1 to 3, characterized in that, The herbicidal composition also contains agriculturally acceptable adjuvants and / or carriers, and is formulated as a dispersible oil suspension or a water-dispersible granule.

5. The ternary herbicidal composition for paddy fields according to claim 4, characterized in that, The total weight percentage of the active ingredient in the herbicidal composition is 20% to 80%, with the remainder being agriculturally acceptable adjuvants and / or carriers.

6. The ternary herbicidal composition for paddy fields according to claim 4, characterized in that, The agriculturally acceptable adjuvants and / or carriers are selected from one or more of emulsifiers, dispersants, wetting agents, antifreeze agents, thickeners, defoamers, solvents, or fillers.

7. The application of the ternary herbicidal composition for paddy fields according to any one of claims 1 to 6 in the control of weeds in paddy fields.

8. The application according to claim 7, characterized in that, The herbicidal composition is applied to the stems and leaves of weeds or to the soil surface in paddy fields.

9. The application according to claim 8, characterized in that, When performing post-emergence foliar treatment, the application is carried out in direct-seeded rice fields or transplanted rice fields, and the application period is after the rice has two leaves and one heart stage and the weeds have two to four leaves. When performing soil sealing treatment, the application is carried out in direct-seeded rice fields before emergence or in transplanted rice fields during the greening period after transplanting.

10. The application according to claim 7, characterized in that, The weeds mentioned are grassy weeds, broadleaf weeds, and sedges in paddy fields, including but not limited to barnyard grass, barnyard grass, crabgrass, water sedge, sedge, duckweed, styrax, knotweed, styrax, sedge ...

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