Suspending agent containing methoxyfenozide-lufenuron and preparation method thereof

Abstract

The invention relates to the technical field of herbicides, in particular to a suspending agent containing methoxyfenozide-lufenuron and a preparation method of the suspending agent. The invention discloses a suspending agent containing methoxyfenozide-lufenuron. The suspending agent is prepared from the following raw materials in percentage by mass: 5%-80% of an active ingredient, 4%-8% of a wetting dispersant, 1.5%-4% of a degradation aid, 0.001%-0.01% of a defoaming agent, 0.05%-0.2% of a thickening agent, 0.05%-0.25% of a stabilizer, 0.01%-0.15% of a preservative and the balance of water, wherein the total mass percent of the raw materials is 100%; wherein the active ingredients comprise methoxyfenozide and lufenuron; the mass ratio of methoxyfenozide to lufenuron is (9-1): (1-9); the auxiliary degradation agent comprises magnetic biochar, a photocatalyst, a coupling agent and starch, and the mass ratio of the magnetic biochar to the photocatalyst to the coupling agent to the starch is (1-3): (1-5): (3-7): (1-10); according to the application, methoxyfenozide and lufenuron are compounded for use, and the ratio of methoxyfenozide to lufenuron is limited, so that the prepared suspending agent is beneficial to improving the control effect on corn grassland spodoptera frugiperda, and meanwhile, the safety to corn is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of herbicides, and in particular to a suspension containing methoxyfenozide-lufenuron and a preparation method thereof. Background Art

[0002] The fall armyworm Spodoptera frugiperda (JE. Smith) belongs to the order Lepidoptera, family Noctuidae, genus Noctua, and is of the same family and genus as the campion moth. Therefore, it has the characteristics of large appetite, diverse diet, many host plants, and a wide range of damage.

[0003] Fall armyworms mainly harm plants of the Gramineae family, and can feed on 186 plants including corn, rice, sorghum, and sugarcane. Since the insect prefers warm climates and cannot hibernate in the north in winter, the fall armyworms harm wheat mainly in the late growth period of wheat, and the crop most seriously harmed is corn. Therefore, how to reduce the harm of fall armyworms has become an important research topic for scientific researchers.

[0004] Methoxyfenozide is a dihydrazide insect growth regulator that simulates the function of natural ecdysone in insects, interacts with ecdysone receptor proteins, and induces premature molting and death in insects. Methoxyfenozide has the characteristics of strong selectivity, low toxicity, low pollution, and little impact on natural enemies and beneficial organisms. Therefore, it is widely used in the control of lepidopteran pests.

[0005] Due to the long-term, large-scale and single use of chemical pesticides, the fall armyworm has developed a high level of resistance to methoxyfenozide. Therefore, how to alleviate the resistance of the fall armyworm to methoxyfenozide, extend the service life of methoxyfenozide, and further improve the control effect of pesticides on the fall armyworm has become an urgent problem to be solved. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present application provides a suspension containing methoxyfenozide-lufenuron and a preparation method thereof.

[0007] In a first aspect, the present application provides a suspension containing methoxyfenozide-lufenuron, using the following technical solution: A suspension containing methoxyfenozide-lufenuron, comprising the following raw materials in percentage by mass: 5%-80% active ingredient, 4%-8% wetting and dispersing agent, 1.5%-4% pro-degradant, 0.001%-0.01% defoamer, 0.05%-0.2% thickener, 0.05%-0.25% stabilizer, 0.01%-0.15% preservative, and water supplemented to 100%; Preferably, the active ingredients include methoxyfenozide and lufenuron; the mass ratio of methoxyfenozide to lufenuron is (9-1):(1-9).

[0008] More preferably, the mass ratio of methoxyfenozide to lufenuron is (3-1):(1-3).

[0009] By adopting the above technical scheme, methoxyfenozide and lufenuron are compounded with the above percentage content, so that there is a good synergistic effect between methoxyfenozide and lufenuron, which helps to improve the control effect of corn fall armyworm while ensuring the safety of corn.

[0010] The degrading aid comprises magnetic biochar, a photocatalyst, a coupling agent and starch, wherein the mass ratio of the magnetic biochar, the photocatalyst, the coupling agent and the starch is (1-3): (1-5): (3-7): (1-10).

[0011] By adopting the above technical solution, the formula of the suspension concentrate is improved, and a degrading agent is added. The added degrading agent uses magnetic biochar as the basic material and is combined with a photocatalyst under the action of a coupling agent to form a highly efficient degrading agent, which can stimulate the production of highly active free radicals under light conditions, effectively accelerate the oxidative decomposition process of pesticide components in the soil, and further improve the prevention and control efficiency.

[0012] In the present application, the formulation of the suspension concentrate is improved, and the added degradation aid can not only adsorb and fix the pesticides in the soil, but also promote their chemical decomposition through the action of surface functional groups, thereby further improving the control efficiency; at the same time, the added biochar itself can improve the soil structure, increase the number and activity of beneficial microorganisms, further improve the self-purification ability of the soil, and reduce the harm to non-target animals and plants.

[0013] Preferably, the preparation steps of the magnetic biochar are as follows: using waste biomass as raw material, loading ferrous ions and ferric ions onto the waste biomass to obtain magnetic biochar.

[0014] Preferably, the waste biomass is at least one of rice straw charcoal, rice husk charcoal, coconut shell charcoal, tobacco straw charcoal, tobacco stem charcoal, reed charcoal, cotton straw charcoal, bamboo charcoal and wood charcoal.

[0015] Preferably, the particle size of the waste biomass is 60-200 mesh.

[0016] Preferably, the amount of waste biomass added is 1-3 g; the amount of iron ions added is 5-15 mL, and the concentration of iron ions is 2.16 mol·L -1 The amount of ferrous ions added is 5-15 mL, and the concentration of ferrous ions is 1.08 mol·L -1 .

[0017] By adopting the above technical solution, the biochar is modified and the adsorption capacity of the biochar is effectively improved. It can not only adsorb pesticides in the soil, but also adsorb heavy metal particles in the soil.

[0018] Preferably, the photocatalyst is copper tungstate / ferroferric oxide photocatalyst.

[0019] By adopting the above technical solution, the added photocatalyst can chemically decompose the pesticide by utilizing its photocatalytic activity under light excitation.

[0020] Preferably, the starch is pretreated in the following steps: starch and deionized water are mixed, and heated at 70-80° C. for 20-40 minutes to obtain gelatinized starch.

[0021] Preferably, the mass volume ratio of the starch to deionized water is (1-3) g: (40-80) mL.

[0022] Preferably, the wetting and dispersing agent includes at least one of phenethylphenol polyether phosphate salt, lignin sulfonate, isomeric tridecanol polyoxyethylene ether, dioctyl sodium sulfosuccinate, alkylphenol polyoxyethylene ether formaldehyde condensation product sodium sulfate, lauryl alcohol polyoxyethylene ether sodium sulfate, alkyl naphthalene sulfonate, alkyl succinic acid sulfonate, fatty alcohol sulfate, and alkylphenol polyoxyethylene ether.

[0023] Preferably, the defoaming agent includes at least one of C10-C20 saturated fatty acid compounds, silicone oil, silicone compounds, and C8-C10 fatty alcohols.

[0024] Preferably, the thickener includes at least one of xanthan gum, magnesium aluminum silicate, lithium magnesium silicate, pectin, gelatin, gum arabic, and magnesium aluminum silicate.

[0025] Preferably, the stabilizer includes at least one of disodium hydrogen phosphate, oxalic acid, sodium sorbate and sodium benzoate.

[0026] Preferably, the preservative includes at least one of isothiazolinone, benzisothiazolinone, formaldehyde and benzoic acid.

[0027] In a second aspect, the present application provides a method for preparing a suspension containing methoxyfenozide-lufenuron, using the following technical solution: A method for preparing a suspension containing methoxyfenozide-lufenuron, the preparation method comprising the following steps: Weigh each raw material according to the formula; Methoxyfenozide, lufenuron, a degrading agent, a wetting dispersant and part of deionized water are coarsely mixed with a homogenizer, and then put into a sand grinder for ultrafine grinding until D90 (90% of the particle size) is less than 5 μm. After the grinding is completed, it is pumped into a high-speed shearing machine, and the remaining deionized water dissolved with a defoamer, a thickener, a stabilizer and a preservative is added, and high-speed shearing is performed. After the shearing is completed, the suspension is obtained.

[0028] In summary, the present application includes at least one of the following beneficial technical effects: The present application discloses a suspension containing methoxyfenozide-lufenuron and a preparation method thereof. Methoxyfenozide and lufenuron are compounded for use, and the ratio of the two is limited. The prepared suspension helps to improve the control effect of corn fall armyworm, while ensuring the safety of corn. The present application discloses a suspension containing methoxyfenozide-lufenuron and a preparation method thereof, which is an environmentally friendly dosage form, reduces environmental pollution and alleviates toxicity. DETAILED DESCRIPTION

[0029] The technical solution of the present application is further illustrated by specific embodiments below. The specific embodiments do not limit the protection scope of the present application; some non-essential modifications and adjustments made by others based on the concept of the present application still fall within the protection scope of the present application.

[0030] The raw materials involved in this application are all commercially available products, and the application is further described in detail below in conjunction with the embodiments and comparative examples.

[0031] Preparation Example 1: Preparation of copper tungstate / ferroferric oxide photocatalyst: 1 g of ferroferric oxide was added to 200 mL of cupric chloride solution (containing 0.6 g of copper chloride), and after magnetic stirring for 18 h, it was slowly dripped into 200 mL of sodium tungstate solution (containing 1.160 g of sodium tungstate) under constant stirring. After continuous stirring for 2 h, the solution was evaporated until about 50 mL remained, and the sample was dried at 60°C to obtain a copper tungstate / ferroferric oxide photocatalyst.

[0032] Preparation Example 2: Preparation of magnetic biochar; 1g of 100-mesh sieved poplar wood powder was added to 500mL of ultrapure water and mixed well. Then 10mL of ferric chloride (2.16mol·L -1 ) and 10mL ferrous chloride (1.08mol·L -1) solution, mixed at 80 ° C for 30 minutes, added 11 mL of ammonia water, continued stirring for 30 minutes, washed alternately with ultrapure water and deionized water for 3 times, dried at 80 ° C, and ground into powder; the powder was placed in a tubular furnace, nitrogen was introduced, calcined at 500 ° C for 2 hours at a heating rate of 10 ° C / min, cooled to room temperature, washed alternately with ultrapure water and deionized water for 3 times, and dried at 60 ° C to obtain magnetic biochar.

[0033] Preparation Example 3: The preparation of the pro-degradant is as follows: (1) Mix 2 g of starch and 60 mL of deionized water, and heat at 75 ° C for 30 minutes to obtain modified starch; (2) 2 g of magnetic biochar, 5 g of coupling agent KH560, and 200 mL of deionized water were mixed for 1 hour, and 3 g of copper tungstate / ferroferric oxide photocatalyst and 5 g of modified starch were added and mixed for 1 hour. The mixture was evaporated until about 100 mL of the solution remained. The mixture was dried at 60 °C, ground and pulverized, and the powder was placed in a tube furnace and calcined at 500 °C for 2 hours at a heating rate of 10 °C / min. The mixture was cooled to room temperature, washed alternately with ultrapure water and deionized water for 3 times, dried at 80 °C, and ground into powder to obtain a degradation aid.

[0034] The copper tungstate / ferroferric oxide photocatalyst was prepared by Preparation Example 1, and the magnetic biochar was prepared by Preparation Example 2.

[0035] Preparation Example 4: The preparation of the pro-degradant is as follows: (1) Mix 1 g of starch and 40 mL of deionized water, and heat at 75 °C for 30 minutes to obtain modified starch; (2) 1 g of magnetic biochar, 3 g of coupling agent KH560, and 200 mL of deionized water were mixed for 1 hour, and 1 g of copper tungstate / ferroferric oxide photocatalyst and 1 g of modified starch were added and mixed for 1 hour. The mixture was evaporated until about 100 mL of the solution remained. The mixture was dried at 60 °C, ground and pulverized, and the powder was placed in a tube furnace and calcined at 500 °C for 2 hours at a heating rate of 10 °C / min. The mixture was cooled to room temperature, washed alternately with ultrapure water and deionized water for 3 times, dried at 80 °C, and ground into powder to obtain a degradation aid.

[0036] The copper tungstate / ferroferric oxide photocatalyst was prepared by Preparation Example 1, and the magnetic biochar was prepared by Preparation Example 2.

[0037] Preparation Example 5: The preparation of the pro-degradant is as follows: (1) Mix 3 g of starch and 80 mL of deionized water, and heat at 75 ° C for 30 minutes to obtain modified starch; (2) 3 g of magnetic biochar, 7 g of coupling agent KH560, and 200 mL of deionized water were mixed for 1 hour, 5 g of copper tungstate / ferroferric oxide photocatalyst and 10 g of modified starch were added and mixed for 1 hour, and the mixture was evaporated until about 100 mL of the solution remained. The mixture was dried at 60 °C, ground and pulverized, and the powder was placed in a tube furnace and calcined at 500 °C for 2 hours at a heating rate of 10 °C / min. The mixture was cooled to room temperature, washed alternately with ultrapure water and deionized water for 3 times, dried at 80 °C, and ground into powder to obtain a degradation aid.

[0038] The copper tungstate / ferroferric oxide photocatalyst was prepared by Preparation Example 1, and the magnetic biochar was prepared by Preparation Example 2.

[0039] Embodiment 1: 20% methoxyfenozide-lufenuron suspension: Formula composition: 15% methoxyfenozide, 5% lufenuron, 6% phenethylphenol polyether phosphate (Soprophor SC), 2.5% degradant, 0.01% silicone defoamer, 0.1% xanthan gum, 0.15% sodium sorbate, 0.1% benzisothiazolinone, and water is added to 100%.

[0040] Methoxyfenozide, lufenuron, a degradant, phenethylphenol polyether phosphate (Soprophor SC), and deionized water (half of the total amount of deionized water) were coarsely mixed with a homogenizer, and then ultra-finely ground in a sand grinder until D90 (90% of the particle size) was less than 5 μm. After the grinding was completed, the mixture was pumped into a high-speed shearing machine, and the remaining deionized water dissolved with an organosilicon defoamer, xanthan gum, sodium sorbate, and benzisothiazolinone was added, and high-speed shearing was performed. After the shearing was completed, the suspension was obtained.

[0041] The degradation aid is prepared by Preparation Example 3.

[0042] Embodiment 2: 15% methoxyfenozide-lufenuron suspension: Formula composition: 10% methoxyfenozide, 5% lufenuron, 6% phenethylphenol polyether phosphate (Soprophor SC), 2.5% degradant, 0.01% silicone defoamer, 0.1% xanthan gum, 0.15% sodium sorbate, 0.1% benzisothiazolinone, and water is added to 100%.

[0043] Methoxyfenozide, lufenuron, a degradant, phenethylphenol polyether phosphate (Soprophor SC) and deionized water (half of the total amount of deionized water) were coarsely mixed with a homogenizer, and then ultra-finely ground in a sand grinder until D90 (90% of the particle size) was less than 5 μm. After the grinding was completed, the mixture was pumped into a high-speed shearing machine, and the remaining deionized water dissolved with an organosilicon defoamer, xanthan gum, sodium sorbate and benzisothiazolinone was added, and high-speed shearing was performed. After the shearing was completed, the suspension was obtained.

[0044] The degradation aid is prepared by Preparation Example 3.

[0045] Embodiment 3: 10% methoxyfenozide-lufenuron suspension: Formula composition: 5% methoxyfenozide, 5% lufenuron, 6% soprophor SC, 2.5% degradant, 0.01% silicone defoamer, 0.1% xanthan gum, 0.15% sodium sorbate, 0.1% benzisothiazolinone, and water is added to 100%.

[0046] Methoxyfenozide, lufenuron, a degradant, phenethylphenol polyether phosphate (Soprophor SC) and deionized water (half of the total amount of deionized water) were coarsely mixed with a homogenizer, and then ultra-finely ground in a sand grinder until D90 (90% of the particle size) was less than 5 μm. After the grinding was completed, the mixture was pumped into a high-speed shearing machine, and the remaining deionized water dissolved with an organosilicon defoamer, xanthan gum, sodium sorbate and benzisothiazolinone was added, and high-speed shearing was performed. After the shearing was completed, the suspension was obtained.

[0047] The degradation aid is prepared by Preparation Example 3.

[0048] Embodiment 4: 15% methoxyfenozide-lufenuron suspension: Formula composition: 5% methoxyfenozide, 10% lufenuron, 6% phenethylphenol polyether phosphate (Soprophor SC), 2.5% degradant, 0.01% silicone defoamer, 0.1% xanthan gum, 0.15% sodium sorbate, 0.1% benzisothiazolinone, water is added to 100%; Methoxyfenozide, lufenuron, a degradant, phenethylphenol polyether phosphate (Soprophor SC) and deionized water (half of the total amount of deionized water) were coarsely mixed with a homogenizer, and then ultra-finely ground in a sand grinder until D90 (90% of the particle size) was less than 5 μm. After the grinding was completed, the mixture was pumped into a high-speed shearing machine, and the remaining deionized water dissolved with an organosilicon defoamer, xanthan gum, sodium sorbate and benzisothiazolinone was added, and high-speed shearing was performed. After the shearing was completed, the suspension was obtained.

[0049] The degradation aid is prepared by Preparation Example 3.

[0050] Embodiment 5: 20% methoxyfenozide-lufenuron suspension: Formula composition: 5% methoxyfenozide, 15% lufenuron, 6% soprophor SC, 2.5% degradant, 0.01% silicone defoamer, 0.1% xanthan gum, 0.15% sodium sorbate, 0.1% benzisothiazolinone, and water is added to 100%.

[0051] Methoxyfenozide, lufenuron, a degradant, phenethylphenol polyether phosphate (Soprophor SC) and deionized water (half of the total amount of deionized water) were coarsely mixed with a homogenizer, and then ultra-finely ground in a sand grinder until D90 (90% of the particle size) was less than 5 μm. After the grinding was completed, the mixture was pumped into a high-speed shearing machine, and the remaining deionized water dissolved with an organosilicon defoamer, xanthan gum, sodium sorbate and benzisothiazolinone was added, and high-speed shearing was performed. After the shearing was completed, the suspension was obtained.

[0052] The degradation aid is prepared by Preparation Example 3.

[0053] Embodiment 6: 5% methoxyfenozide-lufenuron suspension: Formula composition: 3% methoxyfenozide, 2% lufenuron, 4% soprophor SC, 1.5% degradant, 0.001% silicone defoamer, 0.05% xanthan gum, 0.05% sodium sorbate, 0.01% benzisothiazolinone, and water is added to 100%.

[0054] Methoxyfenozide, lufenuron, a degradant, phenethylphenol polyether phosphate (Soprophor SC) and deionized water (half of the total amount of deionized water) were coarsely mixed with a homogenizer, and then ultra-finely ground in a sand grinder until D90 (90% of the particle size) was less than 5 μm. After the grinding was completed, the mixture was pumped into a high-speed shearing machine, and the remaining deionized water dissolved with an organosilicon defoamer, xanthan gum, sodium sorbate and benzisothiazolinone was added, and high-speed shearing was performed. After the shearing was completed, the suspension was obtained.

[0055] The degradation aid is prepared by Preparation Example 3.

[0056] Embodiment 7: 80% methoxyfenozide-lufenuron suspension: Formula composition: 72% methoxyfenozide, 8% lufenuron, 8% phenethylphenol polyether phosphate (Soprophor SC), 4% degradant, 0.01% silicone defoamer, 0.2% xanthan gum, 0.25% sodium sorbate, 0.15% benzisothiazolinone, and water is added to 100%.

[0057] Methoxyfenozide, lufenuron, a degradant, phenethylphenol polyether phosphate (Soprophor SC) and deionized water (half of the total amount of deionized water) were coarsely mixed with a homogenizer, and then ultra-finely ground in a sand grinder until D90 (90% of the particle size) was less than 5 μm. After the grinding was completed, the mixture was pumped into a high-speed shearing machine, and the remaining deionized water dissolved with an organosilicon defoamer, xanthan gum, sodium sorbate and benzisothiazolinone was added, and high-speed shearing was performed. After the shearing was completed, the suspension was obtained.

[0058] The degradation aid is prepared by Preparation Example 4.

[0059] Embodiment 8: 80% methoxyfenozide-lufenuron suspension: Formula composition: 8% methoxyfenozide, 72% lufenuron, 8% phenethylphenol polyether phosphate (Soprophor SC), 4% degradant, 0.01% silicone defoamer, 0.2% xanthan gum, 0.25% sodium sorbate, 0.15% benzisothiazolinone, and water is added to 100%.

[0060] Methoxyfenozide, lufenuron, a degradant, phenethylphenol polyether phosphate (Soprophor SC) and deionized water (half of the total amount of deionized water) were coarsely mixed with a homogenizer, and then ultra-finely ground in a sand grinder until D90 (90% of the particle size) was less than 5 μm. After the grinding was completed, the mixture was pumped into a high-speed shearing machine, and the remaining deionized water dissolved with an organosilicon defoamer, xanthan gum, sodium sorbate and benzisothiazolinone was added, and high-speed shearing was performed. After the shearing was completed, the suspension was obtained.

[0061] The degradation aid was prepared by Preparation Example 5.

[0062] Comparative Example 1: The difference from Example 2 is that no degradation aid is added.

[0063] 15% methoxyfenozide·lufenuron suspension: Formula composition: 10% methoxyfenozide, 5% lufenuron, 6% phenethylphenol polyether phosphate (Soprophor SC), 0.01% silicone defoamer, 0.1% xanthan gum, 0.15% sodium sorbate, 0.1% benzisothiazolinone, and water is added to 100%.

[0064] Methoxyfenozide, lufenuron, phenethylphenol polyether phosphate (Soprophor SC) and deionized water (half of the total amount of deionized water) were coarsely mixed with a homogenizer, and then ultra-finely ground in a sand grinder until D90 (90% of the particle size) was less than 5 μm. After the grinding was completed, the mixture was pumped into a high-speed shearing machine, and the remaining deionized water dissolved with an organosilicon defoamer, xanthan gum, sodium sorbate and benzisothiazolinone was added, and high-speed shearing was performed. After the shearing was completed, the suspension was obtained.

[0065] Performance test 1: Methoxyfenozide-lufenuron suspension control project indicators: The quality of the methoxyfenozide-lufenuron suspension prepared in the above examples and preparation examples was tested. The test indicators are shown in Table 1, and the test results are shown in Table 2: Table 1 Suspension Concentrate Quality Test Items

[0066] Table 2 Test results It can be seen from Table 2 that the performance of the methoxyfenozide-lufenuron suspension prepared by the method of the present application meets the standards.

[0067] Performance test 2: Detection of the co-toxicity coefficient of the combination of methoxyhydrazide and lufenuron against the fall armyworm: 1. Test target The fall armyworm (Spodoptera.fugipenda) was purchased from Henan Keyun Biopesticide Co., Ltd. The larvae were fed with corn leaves at room temperature, and the adults were supplemented with honey water and cultured for generations; the third-instar larvae were selected for use in the experiment.

[0068] 2. Test materials Corn leaves; picked and tested from healthy corn grown in greenhouses.

[0069] 3. Pharmacy 3.1. Test Agents 97% methoxyfenozide technical A, provided by Nanjing Baofeng Pesticide Co., Ltd.; 98% Lufenuron technical B, provided by Nanjing Baofeng Pesticide Co., Ltd.

[0070] A:B=3:1 (C), prepared in Example 1; A:B=2:1 (D), prepared in Example 2; A:B=1:1 (E), prepared in Example 3; A:B=1:2 (F), prepared in Example 4; A:B=1:3 (G), prepared in Example 5.

[0071] 3.2. Dosage of medicine Table 4 Drug test design 3.3. Preparation of medicine Weigh a certain amount of original drug and dissolve it with acetone; dilute the single dose with 0.1% Tween-80 water to the same concentration, and then mix them according to the volume ratio of the composition. Use the gradient dilution method to set 5 series of doses (according to Table 4); and set a treatment without active ingredients, only acetone and Tween-80 as a blank control.

[0072] 3.4. Test material preparation Cut the harvested corn leaves into uniformly sized 4cm long leaves for later use.

[0073] 3.5 Test methods 3.5.1. Chemical treatment Soak the leaves prepared above in the beaker containing the drug solution for 20 seconds, then take them out and place them on a petri dish lined with filter paper in a cool place to dry naturally.

[0074] When treating, treat the blank control first, then treat the single-dose agent in order from low concentration to high concentration, and finally treat the combination agent. Mark the culture dish immediately after each treatment.

[0075] 3.5.2. Inoculation Select 3rd instar larvae with uniform growth in each generation, and inoculate 5 larvae into each dish. After inoculation, cover each dish with a lid and place it at around 26°C, with a relative humidity of 60%-70% and a photoperiod of L:D = (16:8) h for breeding and observation.

[0076] 3.5.3. Experimental Repetition Each replicate had 20 heads and each treatment was replicated 4 times.

[0077] 4. Observation and result statistics 4.1 Results and observations Observe the test results after 96 hours, touch the insect body with a brush to check the death of larvae, record the total number of insects and the number of dead insects, and the test is valid if the control mortality rate is less than 10%.

[0078] 4.2 Calculation of drug efficacy ; ; 4.3 Regression Analysis The results were subjected to regression analysis, and the toxicity equation, LC 50 , LC 90 and its confidence interval.

[0079] 4.4. Calculation of co-toxicity coefficient The co-toxicity coefficient method calculated by Sun Yunpei was used to calculate the co-toxicity coefficient (CTC) of the mixture and determine the synergistic effect of the mixture.

[0080] Take a single agent in the mixture as the standard agent (usually LC 50 The lower one), calculate: Single-dose toxicity index = (LC of standard agent) 50 / a single dose LC 50 )×100; Theoretical toxicity index (TTI) = toxicity index of single agent A × the proportion of single agent A in the mixture + toxicity index of single agent B × the proportion of single agent B in the mixture; Measured Toxicity Index (ATI) = (LC of standard single dose) 50 Value / LC of mixture 50 value)×100; Co-toxicity coefficient = (measured toxicity index / theoretical toxicity index) × 100.

[0081] 5. Results and Analysis Table 5 Co-toxicity coefficient of the combination of methoxyhydrazide and lufenuron against the corn armyworm The results in Table 2 show that the LC of single-dose methoxyfenozide against the corn armyworm 50 and LC 90 The LC values ​​of lufenuron for corn armyworm were 2.948mg / L and 26.476mg / L respectively. 50 and LC 90 They are 0.993 mg / L and 10.532 mg / L respectively.

[0082] LC of five combinations of methoxyfenozide and lufenuron (3:1, 2:1, 1:1, 1:2, 1:3) against fall armyworm 50 The results are as follows: 1.725 mg / L, 1.164 mg / L, 1.223 mg / L, 1.315 mg / L, and 1.366 mg / L, respectively; among them, the 2:1 composition has the highest activity against the fall armyworm, LC 50 It is 1.164mg.

[0083] Performance test 3: Field efficacy test of 15% methoxyfenozide-lufenuron suspension (prepared in Example 2) in controlling corn armyworm 1. Test crops: Corn (variety: Golden Crown 218); the planting method is hole sowing, sown on July 10, 2024, with a planting density of about 2,800 plants / mu, a row spacing of 65 cm, and a plant spacing of 35 cm. The growth of corn plants in the experimental field is basically the same.

[0084] 2. Targets of prevention and treatment: Fall armyworm (Spodoptera frugiperda); 3. Test reagents: Test agent: 15% methoxyfenozide-lufenuron suspension, prepared in Example 2; Control agent: 24% methoxyfenozide suspension, Nanjing Baofeng Pesticide Co., Ltd.; 50 g / L Lufenuron EC, Syngenta Crop Protection GmbH, Switzerland.

[0085] 4. Test system 4.1. Test site information: The area is 2 mu, the previous crop is sorghum, the soil fertility is medium, the cultivation conditions are uniform, the soil is loam, the pH is 4.9, and the organic matter content is 30.7g / kg.

[0086] 4.2. Application method: Spray method: Before applying the pesticide, add the amount of water prepared for the plot (the amount of water added to the sprayer) to calibrate the sprayer and the nozzle, measure the average output, and calculate the required spraying time for each plot based on the sprayer output and the amount of liquid medicine required for the plot; when applying the pesticide, start from one side of the plot and apply the pesticide back and forth, keep the spray width and spray height consistent, apply the pesticide evenly, do not spray repeatedly or miss spray, and a dedicated person will time and control the travel speed; after applying the pesticide in each plot, collect the remaining liquid medicine in the sprayer and calculate the application deviation, which is within ±10%.

[0087] 5. Data analysis and processing methods Use Excel software for raw data statistics and calculations.

[0088] The variance analysis of each treatment result was performed using DPS analysis software and Duncan's new multiple range method (DMRT).

[0089] Calculation formula: ; ; 6. Test results Table 6 Control effect test results 7. Conclusion Analysis According to the table, one day after the application, the control effects of the test agent 15% methoxyfenozide-lufenuron suspension at the dosage of 45, 56.25, and 67.5 g / ha on the fall armyworm were 73.8%, 77.4%, and 82.7%, respectively, while the control effects of the single-dose control agent 24% methoxyfenozide suspension and 50 g / l lufenuron EC were 72.6% and 67.4%, respectively. The results showed that the control effect of the low-dose treatment of the test agent 15% methoxyfenozide-lufenuron suspension was not significantly different from that of the control agent 24% methoxyfenozide suspension, and was significantly higher than that of the control agent 50 g / l lufenuron EC; the control effect of the medium and high-dose treatments of the test agent 15% methoxyfenozide-lufenuron suspension was significantly higher than that of the single-dose control agent 24% methoxyfenozide suspension and 50 g / l lufenuron EC.

[0090] 3, 7, and 14 days after application, the control effects of the test agent 15% methoxyfenozide-lufenuron suspension at the dosage of 45, 56.25, and 67.5 g / ha on corn fall armyworm were between 91.0% and 96.9%, and the control effects of the single-dose control agent 24% methoxyfenozide suspension and 50 g / L lufenuron EC were between 82.4% and 87.6%. The results showed that 3, 7, and 14 days after application, the control effects of the test agent 15% methoxyfenozide-lufenuron suspension at low, medium, and high doses were significantly higher than those of the single-dose control agent 24% methoxyfenozide suspension and 50 g / L lufenuron EC.

[0091] According to Table 4, the control effect of the combined use of methoxyfenozide and lufenuron is significantly better than that of the single use of methoxyfenozide or the single use of lufenuron.

[0092] Performance test 4: Field efficacy test of the methoxyfenozide-lufenuron suspension prepared in the above examples and comparative examples in controlling corn armyworm 1. Test crops: Corn (variety: Golden Crown 218); the planting method is hole sowing, sown on July 10, 2024, with a planting density of about 2,800 plants / mu, a row spacing of 65 cm, and a plant spacing of 35 cm. The growth of corn plants in the experimental field is basically the same.

[0093] 2. Targets of prevention and treatment: Fall armyworm (Spodoptera frugiperda).

[0094] 3. Test reagents: The methoxyfenozide-lufenuron suspension prepared in the above examples and comparative examples.

[0095] 4. Suitable application period and usage: Test site information: The area is 2 mu, the previous crop is sorghum, the soil fertility is medium, the cultivation conditions are uniform, the soil is loam, the pH is 4.9, and the organic matter content is 30.7g / kg.

[0096] Application period: The pesticide should be applied during the corn seedling stage (5-6 leaves), the peak hatching period of fall armyworm eggs to the beginning of the peak occurrence of young larvae.

[0097] Application method: spray; use secondary dilution method to prepare the solution.

[0098] 5. Data analysis and processing methods Same performance test 3; 6. Test results Table 3 Control effect test results According to Table 3, the methoxyfenozide-lufenuron suspension prepared by the method of the present application has a good control effect on the corn armyworm, and the effect of Example 2 is the best.

[0099] Combining Example 2 and Comparative Example 1, it can be seen that the control effect of Example 2 is better than that of Comparative Example 1, which shows that the added degradation aid can degrade the active ingredients in the pesticide and effectively improve the control effect on the corn armyworm.

[0100] Performance test 5: Crop safety test of 15% methoxyfenozide-lufenuron suspension (prepared in Example 2) for controlling corn armyworm: Crop safety test of 15% methoxyfenozide-lufenuron suspension for controlling fall armyworm in corn, testing standard: NY / T 1965.1-2010 "Guidelines for the Evaluation of the Safety of Pesticides on Crops": Part 1 Indoor test methods for the safety evaluation of fungicides and insecticides on crops.

[0101] The corn (Zea mays L.) crops used were Xianyu 335, Caitiannuo 10, and Yuqingzhu 23, all of which were purchased from the seed market.

[0102] Table 7 Results of the crop safety test of 15% methoxyfenozide-lufenuron suspension on corn After the three varieties of Xianyu 335, Caitiannuo No. 10 and Yuqingzhu 23 were treated with 15% methoxyfenozide-fenazuron suspension at three dosages of 30, 60 and 120 ml / mu, no obvious phytotoxicity was observed. The leaves did not wilt, and there was no discoloration, necrosis or deformity such as yellowing, bleaching or chlorosis.

[0103] The inhibition rate of plant height growth rate after treatment with each dose ranged from -3.81% to 1.45%, indicating that 15% methoxyfenozide-lufenuron suspension is safe to use on corn.

Claims

1. A suspension containing methoxyfenozide-lufenuron, characterized in that: The raw materials include the following percentages by weight: active ingredient 5%-80%, wetting and dispersing agent 4%-8%, degradation aid 1.5%-4%, defoaming agent 0.001%-0.01%, thickener 0.05%-0.2%, stabilizer 0.05%-0.25%, preservative 0.01%-0.15%, and water is added to 100%; Wherein, the active ingredients include methoxyfenozide and lufenuron; the mass ratio of methoxyfenozide to lufenuron is (9-1): (1-9); The degrading aid comprises magnetic biochar, a photocatalyst, a coupling agent and starch, wherein the mass ratio of the magnetic biochar, the photocatalyst, the coupling agent and the starch is (1-3): (1-5): (3-7): (1-10).

2. The suspension concentrate containing methoxyfenozide-lufenuron according to claim 1, characterized in that: The mass ratio of methoxyfenozide to lufenuron is (3-1): (1-3).

3. The suspension concentrate containing methoxyfenozide-lufenuron according to claim 1, characterized in that: The preparation steps of the magnetic biochar are as follows: using waste biomass as raw material, loading ferrous ions and ferric ions onto the waste biomass to obtain magnetic biochar.

4. The suspension concentrate containing methoxyfenozide-lufenuron according to claim 3, characterized in that: The waste biomass is at least one of rice straw charcoal, rice husk charcoal, coconut shell charcoal, tobacco straw charcoal, tobacco stem charcoal, reed charcoal, cotton straw charcoal, bamboo charcoal and wood charcoal; the particle size of the waste biomass is 60-200 meshes.

5. The suspension concentrate containing methoxyfenozide-lufenuron according to claim 3, characterized in that: The amount of waste biomass added is 1-3 g; the amount of iron ions added is 5-15 mL, and the concentration of iron ions is 2.16 mol·L -1 The amount of ferrous ions added is 5-15 mL, and the concentration of ferrous ions is 1.08 mol·L -1 .

6. The suspension concentrate containing methoxyfenozide-lufenuron according to claim 1, characterized in that: The photocatalyst is copper tungstate / ferroferric oxide photocatalyst.

7. The suspension concentrate containing methoxyfenozide-lufenuron according to claim 1, characterized in that: The starch is pretreated in the following steps: starch and deionized water are mixed, and heated at 70-80° C. for 20-40 minutes to obtain gelatinized starch.

8. The suspension concentrate containing methoxyfenozide-lufenuron according to claim 7, characterized in that: The mass volume ratio of the starch and deionized water is (1-3) g: (40-80) mL.

9. The suspension concentrate containing methoxyfenozide-lufenuron according to claim 1, characterized in that: The wetting and dispersing agent includes at least one of phenethylphenol polyether phosphate salt, lignin sulfonate, isomeric tridecanol polyoxyethylene ether, dioctyl sodium sulfosuccinate, alkylphenol polyoxyethylene ether formaldehyde condensation product sodium sulfate, lauryl alcohol polyoxyethylene ether sodium sulfate, alkyl naphthalene sulfonate, alkyl succinic acid sulfonate, fatty alcohol sulfate, and alkylphenol polyoxyethylene ether; The defoaming agent includes at least one of C10-C20 saturated fatty acid compounds, silicone oil, silicone compounds, and C8-C10 fatty alcohols; The thickener comprises at least one of xanthan gum, magnesium aluminum silicate, lithium magnesium silicate, pectin, gelatin, gum arabic, and magnesium aluminum silicate; The stabilizer includes at least one of disodium hydrogen phosphate, oxalic acid, sodium sorbate, and sodium benzoate; The preservative includes at least one of isothiazolinone, benzisothiazolinone, formaldehyde and benzoic acid.

10. A method for preparing a suspension containing methoxyfenozide-lufenuron, characterized in that: The preparation method steps are as follows: Weigh each raw material according to the formula; Methoxyfenozide, lufenuron, a degrading agent, a wetting dispersant and part of deionized water are coarsely mixed with a homogenizer, and then put into a sand grinder for ultrafine grinding until D90 (90% of the particle size) is less than 5 μm. After the grinding is completed, it is pumped into a high-speed shearing machine, and the remaining deionized water dissolved with a defoamer, a thickener, a stabilizer and a preservative is added, and high-speed shearing is performed. After the shearing is completed, the suspension is obtained.

Images