A herbicidal composition containing dichloroisoniximone and difenoxuron

Abstract

The present application belongs to the technical field of pesticides, and particularly relates to a herbicide composition containing dichloroisoxyacetone and difenoxuron. The herbicide composition contains dichloroisoxyacetone and difenoxuron as effective components, and the mass ratio of dichloroisoxyacetone to difenoxuron is 1:1.25-10. The herbicide composition has excellent control effect. The excellent control effect is reflected in two aspects: first, dichloroisoxyacetone and difenoxuron have a significant synergistic effect through reasonable combination and proportioning, which can greatly improve the control effect on weeds and reduce the amount of herbicide. Second, dichloroisoxyacetone can prevent and control gramineous weeds and broadleaf weeds, while difenoxuron mainly prevents and controls broadleaf weeds and also has a certain effect on gramineous weeds. The combination of the two can expand the herbicidal spectrum and significantly improve the comprehensive control effect on weeds.

Description

Technical Field

[0001] This invention belongs to the field of pesticide technology, specifically relating to a herbicide composition containing dichloroisoxane and pyrfluthrin. Background Technology

[0002] Farmland weeds compete with wheat for sunlight, water, and nutrients, seriously threatening the normal growth and stable production of wheat. Herbicides remain the most economical and effective means of controlling weeds in modern agriculture; however, their widespread and prolonged use has also led to problems such as weed community succession and herbicide resistance. Therefore, developing highly efficient and green herbicide compositions that can effectively control weeds in wheat fields, especially herbicide-resistant weeds, is of great significance.

[0003] Bixlozone, CAS: 81777-95-9, Molecular formula: C 12 H 13 Cl2NO2, structural formula as follows:

[0004]

[0005] Dichloroisoxane is an isoxazoline herbicide developed by FMC Corporation. Its mechanism of action involves absorption through roots and young shoots, followed by translocation upwards to all parts of the plant via transpiration. It inhibits the activity of 1-deoxy-D-xyulose-5-phosphate synthase, thereby disrupting the biosynthesis of plastid isoprene, i.e., carotenoids. Carotenoids protect chlorophyll in plant cells; when carotenoids lose their protective function, the plant's leaves turn white. Susceptible weeds cannot metabolize dichloroisoxane and ultimately die from photosynthesis. Dichloroisoxane is widely used in fruit trees, vegetables, cotton, barley, wheat, rapeseed, and rice, controlling both grassy and broadleaf weeds.

[0006] Diflufenican, CAS: 83164-33-4, molecular formula C 19 H 11 F5N2O2, structural formula as follows:

[0007]

[0008] Pyrfluthrin is an amide herbicide belonging to the phytoene dehydrogenase inhibitor class. It inhibits the biosynthesis of carotenoids in weeds and disrupts weed cell membranes and chlorophyll synthesis, thereby achieving contact weed control. Pyrfluthrin is a broad-spectrum selective wheat field herbicide that can be applied from wheat sowing to jointing. It has both soil-applied and foliar-applied activity and can control most broadleaf weeds, including cleavers, purslane, chickweed, amaranth, dayflower, shepherd's purse, and bindweed.

[0009] Combining different pesticide active ingredients is an effective and rapid approach to developing and researching novel herbicides. The combined active ingredients typically exhibit three types of effects: antagonistic, additive, and synergistic. Formulas exhibiting synergistic effects can significantly improve the control of target weeds and reduce pesticide dosage. Through long-term research, the inventors unexpectedly discovered that combining dichlorvos and pyrifluquinazon in an appropriate mass ratio can greatly improve weed control and reduce herbicide usage, particularly demonstrating excellent control of herbicide-resistant ryegrass.

[0010] There are currently no reports of combining dichlorvos with pyrfluthrin. Summary of the Invention

[0011] The purpose of this invention is to provide a herbicide composition containing dichlorvos and pyrifluquinazon, which, when applied as a soil spray after wheat seedling sowing but before emergence, can improve the control of grass or broadleaf weeds and reduce the amount of herbicide used, especially showing significant control of herbicide-resistant ryegrass.

[0012] To achieve the above objectives, the present invention provides the following technical solution:

[0013] A herbicide composition containing dichloroisoxane and pyrfluthrin, wherein the active ingredient is a compound of dichloroisoxane and pyrfluthrin, wherein the mass ratio of dichloroisoxane to pyrfluthrin is 1:1.25-10.

[0014] For even better results, the mass ratio of dichloroisoxane to pyrfluthrin is 1:5.

[0015] Another object of the present invention is to provide a herbicide comprising the herbicide composition and an adjuvant permitted to be added to the pesticide.

[0016] More specifically, the herbicide composition accounts for 10-60% of the total mass of the herbicide.

[0017] More specifically, the additive is selected from one or more of surfactants, wetting agents, dispersants, fillers, emulsifiers, disintegrants, stabilizers, defoamers, thickeners, antifreeze agents, and solvents.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] (1) The herbicide composition of this invention exhibits excellent control effects. These excellent effects are reflected in two aspects: First, the rational combination of dichlorvos and pyrifluquinazon has a significant synergistic effect, greatly improving the control effect on weeds while reducing the amount of herbicide used. Second, dichlorvos controls both grassy and broadleaf weeds; while pyrifluquinazon primarily controls broadleaf weeds, but also has some effect on grassy weeds. The combination of the two broadens the weed control spectrum and significantly improves the overall control effect on weeds.

[0020] (2) The herbicidal composition of this invention can effectively control resistant weeds in wheat fields, especially resistant grass weeds such as ryegrass. Herbicide resistance is widespread in wheat fields, with severe resistance to commonly used herbicides such as quizalofop-p-ethyl, clodinafop-propargyl, clodinafop-propargyl, mesosulfuron-methyl, and pyrazosulfuron-methyl. Isoxaflubenzuron is a deoxy-D-xylulose phosphate synthase inhibitor, while pyrflumetochlor is a lycopene dehydrogenase inhibitor. These two herbicides have completely different mechanisms of action, and there are currently no reports of weeds developing resistance to either of these herbicides. Selecting highly effective herbicides with completely different mechanisms of action is an important strategy for managing weed resistance and delaying its development. The combination of isoxaflubenzuron and pyrflumetochlor can effectively control resistant weeds, especially resistant ryegrass. Detailed Implementation

[0021] The technical solution of this invention patent will be clearly and completely described below.

[0022] Example 1 Indoor bioactivity test

[0023] 1. Test weeds

[0024] The seeds of multiflora ryegrass (Lolium multiflorum, a herbicide-resistant grass) were collected in 2017 from a wheat field in Runan County, Zhumadian City, Henan Province.

[0025] Seeds of Veronica persica (a broadleaf weed) were collected in 2020 from a wheat field in Yuanyang County, Xinxiang, Henan Province.

[0026] In previous experiments, it was found that the tested ryegrass populations exhibited varying degrees of resistance to multiple existing herbicides, including quizalofop-p-ethyl, acesulfame potassium, clodinafop-propargyl, and fluazinam. For details, see "Resistance of Ryegrass to ACCase and ALS Inhibitors in Henan Province and Analysis of Target Gene Mutations" (Xu Hongle et al., Institute of Plant Protection, Henan Academy of Agricultural Sciences, Journal of Plant Protection, 2023, 50(1): 224-230).

[0027] 2. Test reagents

[0028] The 96% dichlorvos technical grade and the 98% pyrifluquinazon technical grade were both obtained from the laboratory of the Institute of Plant Protection, Henan Academy of Agricultural Sciences.

[0029] After the test reagent is completely dissolved in acetone, it is added to an aqueous solution containing 0.1 wt% Tween-80, stirred evenly, and prepared into a solution containing a certain active ingredient for later use.

[0030] 3. Test Methods

[0031] The test weed seeds were evenly sown in plastic pots (10 cm high, 8 cm in diameter) filled with soil, with 12 seeds sown in each pot. After sowing, the pots were covered with 0.5 cm of soil and placed in a greenhouse at 20°C during the day and 10°C at night. One day later, the soil was sprayed with the solutions listed in Tables 1 and 2, with each treatment repeated four times. A blank control was set up by spraying an equal volume of 0.1 wt% Tween-80 aqueous solution. After treatment, the test materials were placed in the greenhouse for continued cultivation, and the growth of the weeds was observed regularly. After 21 days, the fresh weight of the above-ground parts of the weeds was weighed, and the fresh weight inhibition rate (%) was calculated.

[0032]

[0033] 4. Evaluation of combined effects

[0034] The Gowing method is used to evaluate the combined action of herbicides, and the calculation formula is as follows:

[0035]

[0036] In the formula:

[0037] X -- Weed control efficacy of herbicide A at dosage P;

[0038] Y -- Weed control efficacy of herbicide B at a dosage of Q;

[0039] E0 -- Theoretical efficacy of herbicide A at dosage P + Theoretical efficacy of herbicide B at dosage Q;

[0040] E – The actual control effect of herbicide A and herbicide B when mixed in the above proportions.

[0041] 5. Evaluation Criteria

[0042] E-E0 > 10% indicates a synergistic effect; E-E0 < -10% indicates an antagonistic effect; E-E0 values ​​between ±10% indicate an additive effect. The results are shown in Table 1-2.

[0043] Table 1. Herbicidal activity of different ratios of dichlorvos and pyrfluthrin against Lorrae rubrum.

[0044]

[0045]

[0046] Table 1 shows that dichloroisoxane alone has a certain control effect on ryegrass, but the dosage must reach 180 g / hm. 2 At this time, its fresh weight inhibition rate against ryegrass can reach over 90%. However, pyrifluquinazon alone has almost no control effect on ryegrass, even at a dosage of 900 g / hm². 2 At that time, its fresh weight inhibition rate against ryegrass was only 64.64%. However, when dichlorvos and pyrifluquinazon were combined, within the range of 1:1.25-10, they showed an additive or synergistic effect on the control of ryegrass. Compared with single active ingredients, they could greatly improve the control effect against ryegrass, especially when dichlorvos (45g / hm) was used. 2 ) and pyrifluquinazon (225 g / hm) 2 The synergistic effect is optimal when the ratio is 1:5. This indicates that the herbicidal composition of the present invention, which is a combination of dichloroisoxane and pyrifluquinazon, can improve the control effect on the herbicide-resistant weed, ryegrass.

[0047] Table 2. Herbicidal activity of different ratios of dichloroisoxane and pyrfluthrin against Veronica persica.

[0048]

[0049]

[0050] As shown in Table 2, when dichlorvos and pyrifluquinazon are combined, they exhibit an additive effect on the control of ryegrass in the range of 1:2.5-20, which can broaden the weed control spectrum and improve the overall control effect on weeds.

[0051] Example 2 48% dichlorvos·pyrfluthrin suspension concentrate

[0052] Dichloroisoxane 8%, pyrfluthrin 40%, sodium diisooctyl succinate sulfonate 2wt%, sodium dodecyl sulfate 2wt%, ethylene glycol 3wt%, sodium lignosulfonate 2.5%, carboxymethyl cellulose 0.2wt%, dimethyl silicone oil 0.2wt%, water to 100%.

[0053] Example 3 35% dichlorvos·pyrfluthrin suspension concentrate

[0054] 10% dichloroisoxamethonium, 25% pyrfluthrin, 2 wt% sodium diisooctyl succinate sulfonate, 2 wt% sodium dodecyl sulfate, 3 wt% ethylene glycol, 2.5% sodium lignosulfonate, 0.2 wt% carboxymethyl cellulose, 0.2 wt% dimethyl silicone oil, and water to make up to 100%.

[0055] Example 4 Field efficacy trials

[0056] 1. Test crop: Wheat (Bainong 207)

[0057] 2. Test reagents

[0058] Example 2: 48% dichloroisoxane·pyrfluthrin suspension concentrate

[0059] Example 3: 35% dichloroisoxane·pyrfluthrin suspension concentrate

[0060] 36% dichloroisoxazone suspension concentrate (FMC Corporation, USA, commercially available)

[0061] 50% Pyrfluthrin Wettable Powder (Adomai Huifeng (Jiangsu) Co., Ltd., purchased commercially)

[0062] 3. Target of prevention and control

[0063] Grass weeds: Lorula multiflora and Alopecurus australis, with Lorula multiflora being the dominant weed;

[0064] Broadleaf weeds: Arabian speedwell and shepherd's purse, with Arabian speedwell being the dominant weed.

[0065] 4. Test methods (GB / T17980.41-2000 Guidelines for Field Efficacy Testing of Pesticides (I) Herbicides for the Control of Weeds in Wheat Crops)

[0066]

[0067]

[0068] The experimental plot area was 20m². 2 The experiment was repeated four times, with all experimental plots having uniform cultivation conditions (soil, fertility, growth stage, and row spacing). The plots for the experimental herbicide and the control were arranged in a randomized block design. Soil fogging was applied after wheat sowing but before emergence. Weed control efficacy was assessed 42 days post-application, and herbicide damage was graded. At harvest, 10 m³ of herbicide was collected from each plot. 2 Yield testing was conducted. Test treatments and numbering are shown in Table 3.

[0069] Table 3. Test Treatments and Numbering

[0070] No. Treatment Ingredient dose (g / hm 2 )]]> 1 Example 2: 48% clomazone + difenoxuron suspension concentrate 270 2 Example 2: 48% clomazone + difenoxuron suspension concentrate 540 3 Example 3: 35% clomazone + difenoxuron suspension concentrate 157.5 4 Example 3: 35% clomazone + difenoxuron suspension concentrate 315 5 36% clomazone suspension concentrate 180 6 50% difenoxuron wettable powder 225 7 Hand weeding - 8 Water control -

[0071] 5. Grading standards for the safety of herbicide compositions for wheat

[0072] See Table 4.

[0073] Table 4. Grading Standards for the Safety of Herbicide Compositions on Wheat

[0074] Scale Crop symptom 1st Crop normal growth, no any injury symptom 2nd Crop slight phytotoxicity, phytotoxicity less than 10% 3rd Crop moderate phytotoxicity, can recover later, no effect on yield 4th Crop heavy phytotoxicity, difficult to recover, cause yield reduction 5th Crop serious phytotoxicity, can not recover, cause obvious yield reduction or no yield

[0075] 6. Test Results

[0076] The results are shown in Table 5.

[0077] Table 5. Field control efficacy and safety of herbicide compositions.

[0078]

[0079] Note: The efficacy in the table is the average of four replicates; abc represent the significance of the differences between treatments at the p=0.05 level.

[0080] Table 5 shows that in the field trials, different treatments exhibited significant differences in plant control efficacy and fresh weight control efficacy against gramineous weeds, broadleaf weeds, and total weeds. Treatments 1-4, i.e., different dosages of Examples 2 and 3, showed significantly higher plant control efficacy and fresh weight control efficacy against total weeds than treatments 5 and 6. Specifically, treatment 2 showed higher plant control efficacy and fresh weight control efficacy against gramineous weeds, broadleaf weeds, and total weeds than the other treatments. This indicates that the herbicide composition of dichlorvos and pyrifluquinazon in this invention has a significant synergistic effect compared to using either herbicide alone, and exhibits excellent control efficacy against both gramineous and broadleaf weeds; furthermore, this composition also demonstrates high safety for wheat.

[0081] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. Use of a herbicidal composition comprising dichloroisoniximone and difenoxure in the control of resistant weeds of Lolium multiflorum, characterized in that, The effective component of the herbicide composition is compounded by dichloroisoxy- furon and difenol, and the mass ratio of dichloroisoxy-furon and difenol is 1:5-10.

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