Rapid preliminary screening evaluation method for chemical prevention and control active ingredients of meadow moth

Abstract

The invention discloses a rapid preliminary screening evaluation method for chemical prevention and control active components of meadow moth, which comprises the following steps: (1) evaluating the activity of chemical prevention and control active components to be detected on larvae of meadow moth moth through indoor bioassay to obtain basic score data of the chemical prevention and control active components to be detected; (2) selecting other farmland pests which are damaged with the meadow moth in the same period, and evaluating the activity of the chemical prevention and control active components to be detected through indoor bioassay to obtain additional score data; (3) selecting a main environmental non-target organism, and determining acute toxicity data of the to-be-detected effective component to the environmental non-target organism through public database query or test to obtain score deduction data; (4) comprehensively scoring the chemical prevention and control active components to be detected; and (5) grading according to the comprehensive score, and giving a recommendation conclusion to the chemical prevention and treatment active components to be detected. By means of the evaluation method, the efficient and low-toxicity emergency chemical prevention and control active ingredients of the meadow moth can be rapidly and preliminarily screened, and therefore the purpose of guiding emergency chemical prevention and control of the meadow moth is achieved.

Description

Technical Field

[0001] The invention relates to the field of chemical control of agricultural pests and diseases, in particular to a method for rapid primary screening and evaluation of active ingredients for chemical control of meadow moths. Background Art

[0002] The fall borer (Loxostege sticticalis L.) is a major migratory lepidopteran pest of agriculture and animal husbandry in North my country, Northeast China, and Northwest China (the "Three Norths"), characterized by its polyphagous nature and intermittent outbreaks. Currently, chemical control remains the most effective method, but the only registered pesticides for fall borer control in my country are 20% triazophos emulsifiable concentrate and 20% chlorambucil-triazophos emulsifiable concentrate. Due to the relatively low incidence of fall borer damage in recent years, production of these two products has been low, driven by concerns about sales and economic benefits. These pesticides are even difficult to purchase commercially. In actual production, if intermittent outbreaks occur, this falls far short of meeting the actual control needs. Existing literature reporting on the effectiveness of chemical agents for fall borer control is limited, and the few studies that have been published are mostly limited to investigations of indoor activity and field efficacy, lacking experimental evaluation and comprehensive consideration of environmental safety. To complete the formal registration of a chemical product for controlling grassland borers, an enterprise needs to go through a series of complex tests and registration review processes including product chemistry, toxicology, efficacy, residues, and environmental impacts, which requires a lot of time, manpower, material and financial resources. Considering the intermittent and sporadic characteristics of grassland borers and the instability of subsequent product sales benefits, enterprises are not very enthusiastic about applying for registration of chemical products related to controlling grassland borers.

[0003] Asian corn borer (Ostrinia furnacalis) and fall armyworm (Spodoptera frugiperda) are two important lepidopteran pests in agricultural production. In fields where fall armyworm is being controlled, there is a high possibility of simultaneous damage. Therefore, they can be included in the screening and evaluation system of fall armyworm control agents from the perspective of "one drug for multiple preventions".

[0004] In order to better respond to possible intermittent outbreaks of meadow borer in my country and provide scientific data support for emergency chemical control of meadow borer in my country, while strengthening the dynamic monitoring of meadow borer populations and research on damage patterns, it is urgent to establish a set of rapid initial screening and evaluation methods for active ingredients of high-efficiency and low-toxic emergency chemical control of meadow borer, which can be used to quickly screen out a list of alternative agents and propose effective and environmentally safe emergency chemical control technologies. Summary of the Invention

[0005] In response to the above-mentioned problems, the present invention proposes a rapid initial screening and evaluation method for active ingredients for chemical control of grassland borers. Using this evaluation method, high-efficiency and low-toxic emergency chemical control active ingredients for grassland borers can be quickly screened, thereby achieving the purpose of guiding emergency chemical control of grassland borers.

[0006] To achieve the above object, the present invention is implemented according to the following technical solutions:

[0007] A rapid initial screening and evaluation method for chemical control active ingredients for meadow moth borers comprises the following steps:

[0008] Step S1: Conducting an indoor bioassay to evaluate the activity of the tested chemical control active ingredient against the larvae of the meadow moth using the insect immersion method to obtain its basic score data M. The score is classified according to Table 1:

[0009] Table 1 Basic score data M score division basis

[0010]

[0011] The activity of the agent against the meadow moth is the core part of this screening and evaluation method, so the highest score is 100 points, and the specific score is divided into four levels according to the activity level.

[0012] Step S2: Select two other farmland pests that occur at the same time as the meadow moth: Pest I and Pest II. Evaluate the activity of the tested chemical control active ingredient against them through indoor bioassays to obtain two bonus points, PⅠ and PⅡ, with a maximum of 10 points for each. The bonus points PⅠ and PⅡ are scored according to Table 2:

[0013] Table 2: Basis for scoring bonus items

[0014]

[0015] The Asian corn borer (Ostrinia furnacalis) and the fall armyworm (Spodoptera frugiperda) are two important lepidopteran pests in agricultural production. In fields where these pests are being controlled, they are likely to infest fields simultaneously. Therefore, they can be incorporated into the screening and evaluation system for these insecticides from the perspective of "one agent for multiple preventions." The activity of the insecticide against these pests is a secondary component of this screening and evaluation process. Therefore, it is considered a bonus point, with each target pest scored out of a maximum of 10 points. The activity level is divided into four bonus tiers.

[0016] Step S3: Select environmental non-target organisms, including birds, bees, fish and earthworms, and determine the acute toxicity data of the tested chemical control active ingredients on environmental non-target organisms through public database query or experimental measurement, and obtain 6 deduction items: acute oral toxicity LD50 to birds 50 Value NI, acute feeding toxicity LC for birds 50 Value NⅡ, acute oral toxicity to bees LD50 50 (48h) value NⅢ, acute contact toxicity to bees LD 50(48h) value NIV, acute toxicity LC to fish 50 (96h) value NV and acute toxicity LC to earthworms 50 (14d) Value NVI, each item will be deducted up to 20 points. The deduction items are scored according to Tables 3.1 to 3.4:

[0017] Table 3.1 Basis for NI or NII score classification

[0018]

[0019] Table 3.2 Basis for NⅢ or NⅣ score division

[0020]

[0021] Table 3.3NⅤ score classification basis

[0022]

[0023]

[0024] Table 3.4NVI score classification basis

[0025]

[0026] The selection of major environmental non-target organisms is based on selecting one typical non-target organism from each of the four different spatial dimensions of air, soil, water, and plants, namely, aerial birds, soil organisms earthworms, aquatic organisms fish, and plant pollinating insects bees as the assessment criteria for environmental safety. Birds involve acute oral toxicity and acute feeding toxicity, bees involve acute oral toxicity and acute contact toxicity, and fish and earthworms only involve acute toxicity, a total of 6 indicators, each with a maximum deduction of 20 points, for a total of 120 points. The toxicity level of each indicator is divided with reference to the national standards for the corresponding toxicity determination methods. The maximum deduction is 120 points, which is consistent with the maximum score of 120 points (basic score of 100 points + 20 points for bonus items).

[0027] Step S4: Calculate the comprehensive score S of the tested chemical control active ingredient according to the following formula:

[0028] S=M+PⅠ+PⅡ+NⅠ+NⅡ+NⅢ+NⅣ+NⅤ+NⅥ;

[0029] Step S5: Classify the levels according to Table 4 based on the comprehensive scores and give a recommended conclusion for the tested chemical control active ingredients;

[0030] Table 4 Comprehensive scoring classification basis

[0031] Recommended Conclusion S Strongly not recommended S≤50 Not recommended 50<S≤70 General Recommendations 70<S≤90 Recommended S>90.0

[0032] The corresponding score division is consistent with the general understanding in the industry, and converts the four common levels of excellent, good, medium and poor in the industry into recommendation conclusions of key recommendation, general recommendation, not recommended and strongly not recommended, which is more instructive for the rapid selection of drugs for emergency prevention and control in production.

[0033] In the above technical solution, step S1 is to conduct an indoor bioassay to evaluate the activity of the tested chemical control active ingredient against the larvae of the fall moth by the insect immersion method in accordance with the agricultural industry standard "Guidelines for Indoor Bioassay Tests of Pesticides - Insecticides Part 6: Insecticidal Activity Tests - Insect Immersion Method" (NY / T1154.6-2006), which includes the following steps:

[0034] (1) Test material preparation: Three-instar larvae of Sedge borer, which were raised indoors, of uniform size and healthy, were selected for the test.

[0035] (2) Preparation of reagents: Water-soluble reagents are directly dissolved in water, and other reagents are dissolved in appropriate organic solvents and then diluted with water. Based on the results of the preliminary test, five series of mass concentrations are set according to the proportional method for formal testing.

[0036] (3) Chemical treatment: Immerse the larvae in the chemical solution for 10 seconds, then remove the excess solution with filter paper. Transfer the larvae to normal conditions for rearing. Each treatment was repeated four times, with 10 larvae immersed in each replicate. A control treatment containing the corresponding organic solvent without the chemical was also included.

[0037] (4) Result investigation: The death of the grass moth larvae was investigated and recorded every 24 hours after the treatment. After the 72-hour test, the number of dead insects and the survival rate were statistically analyzed to calculate the half-lethal concentration (LC). 50 The values and 95% confidence limits were used to evaluate the stomach poison activity of the test agents against the larvae of S. frugiperda.

[0038] In the above technical solution, step S2 includes the following steps of evaluating the activity of the tested chemical control active ingredient against pests I and II through indoor bioassay in accordance with the agricultural industry standard "Guidelines for Indoor Bioassay Tests of Pesticides - Insecticides - Part 6: Insecticide Activity Test - Insect Immersion Method" (NY / T 1154.6):

[0039] (1) Preparation of test materials: Select 3rd instar pest larvae that are raised indoors, uniform in size and healthy.

[0040] (2) Preparation of reagents: Water-soluble reagents are directly dissolved in water, and other reagents are dissolved in appropriate organic solvents and then diluted with water. Based on the results of the preliminary test, five series of mass concentrations are set according to the proportional method for formal testing.

[0041] (3) Chemical treatment: Immerse the target insects in the chemical solution for 10 seconds, then remove the excess solution with filter paper and transfer the insects to normal conditions for rearing. Each treatment was repeated four times, with 10 insects immersed in each repetition. A control treatment containing the corresponding organic solvent without the chemical was also included.

[0042] (4) Result investigation: After treatment, the death of test insects was investigated and recorded every 24 hours. After the 72-hour test, the number of dead insects and the survival rate of test insects were statistically analyzed to calculate the half-lethal concentration (LC). 50 The values and 95% confidence limits were used to evaluate the stomach poison activity of the test agents against pests.

[0043] In the above technical solution, the step S3 refers to the national standard "Test Guidelines for Environmental Safety Evaluation of Chemical Pesticides Part 9: Acute Toxicity Test for Birds" (GB / T 31270.9) and determines the acute toxicity data of the tested chemical control active ingredient to non-target birds in the aerial environment (recommended to be Japanese quail Coturnix coturnix japonica) by testing, which includes the following steps:

[0044] a. Acute oral toxicity test steps

[0045] (1) Preliminary test: Under the conditions of the formal test, set up five concentration groups with large intervals, and determine the lowest lethal concentration and the highest survival concentration of the test substance for the test birds. Within this range, set the concentration for the formal test.

[0046] (2) Formal test: According to the concentration range determined in the preliminary test, 5 concentration groups are set at a certain interval, with 10 birds in each group, half male and half female, and a blank control group. If solvent is used for solubilization, a solvent control group is also required. There is no repetition between the control group and each concentration group, and the concentration difference between the concentration groups shall not exceed 2 times. Observe and record the poisoning symptoms and deaths of the test birds every 24 hours. After the test, the data are statistically analyzed to calculate the half-lethal concentration (LD) 50 Values and 95% confidence limits.

[0047] (3) Limit test: Based on the pesticide toxicity classification standard for birds, the upper limit dose is set at 2000 mg ai / kg body weight. That is, if no bird dies when the test substance reaches 2000 mg ai / kg body weight, there is no need to continue the test. At this point, the test substance can be judged to have low oral toxicity to birds.

[0048] b. Acute feeding toxicity test procedures

[0049] (1) Preliminary test: Under the conditions of the formal test, set up five concentration groups with large intervals, and determine the lowest lethal concentration and the highest survival concentration of the test substance for the test birds. Within this range, set the concentration for the formal test.

[0050] (2) Formal test: According to the concentration range determined in the preliminary test, 5 concentration groups are set at a certain interval, with 10 birds in each group, half male and half female, and a blank control group is set up. The blank control group is fed with normal feed. If solvent is used to assist solubilization, a solvent control group is also required. There are no repetitions in the control group and each concentration group, and the concentration difference between concentration groups shall not exceed 2 times. Observe and record the poisoning symptoms and deaths of the test birds every 24 hours. After the test, the data are statistically analyzed to calculate the half-lethal concentration (LC) 50 Values and 95% confidence limits.

[0051] (3) Limit test: Based on the pesticide toxicity classification standard for birds, an upper limit dose of 5000 mg ai / kg feed is set. That is, if no bird deaths occur when the test substance reaches 5000 mg ai / kg feed, there is no need to continue the test. At this point, the test substance can be judged to have low feeding toxicity to birds.

[0052] In the above technical solution, the step S3 refers to the national standard "Test Guidelines for Environmental Safety Assessment of Chemical Pesticides Part 10: Acute Toxicity Test for Bees" (GB / T 31270.10) and determines the acute toxicity data of the tested chemical control active ingredient to non-target bees in the plant pollination environment (preferably adult Italian worker bees Apis mellifera L.) by testing, including the following steps:

[0053] a. Acute oral toxicity test steps

[0054] (1) Preliminary test: According to the conditions of the formal test, five dose groups are set up with a large interval. The minimum lethal dose and the maximum survival dose of the test bees are determined through the preliminary test.

[0055] (2) Formal test: According to the concentration range determined in the preliminary test, 5 dose groups were set up with a certain proportional interval (the geometric difference should be controlled within 2.2), with 10 bees in each group, and a blank control group was set up. If organic solvents were used for solubilization, a solvent control group should be added. The bees in the storage cage were introduced into the test cage, and then 100 μL of 50% (mass concentration) sucrose water bath containing different concentrations of the test substance was added to the feeder, and the consumption of the drug solution in each group was measured. Once the drug solution was consumed (usually 3 to 4 hours), the food container was removed and replaced with sucrose water without the test substance for feeding (unlimited). For some test substances, the bees refused to eat at higher test doses, resulting in little or no food consumption. The time was extended to 6 hours at most, and the food consumption was measured (i.e., the volume or weight of the food remaining in the treatment was measured). There were 3 replicates for the control group and each treatment group. The poisoning symptoms and the number of deaths were observed and recorded 24 hours and 48 hours after treatment. If the mortality rate of the control group is less than 10%, if the difference in mortality rate after 24 hours and 48 hours of treatment reaches 10%, the observation time should be extended to a maximum of 96 hours. After the test, the data will be statistically analyzed to calculate the half-lethal concentration (LC50). 50 Values and 95% confidence limits.

[0056] (3) Limit test: set the upper limit dose to 100μg ai / bee, that is, if the bees do not die when the test substance reaches 100μg ai / bee, there is no need to continue the test.

[0057] ai / bee, the maximum solubility is used as the upper limit concentration.

[0058] b. Acute contact toxicity test steps

[0059] (1) Preliminary test: According to the conditions of the formal test, five dose groups are set up with a large interval. The minimum lethal dose and the maximum survival dose of the test bees are determined through the preliminary test.

[0060] (2) Formal test: According to the concentration range determined in the preliminary test, 5 dosage groups were set up with a certain proportional interval (the geometric difference should be controlled within 2.2), with 10 bees in each group, and a blank control group and a solvent control group were set up. The control group and each treatment group were set up with 3 replicates. The test substance was dissolved in acetone and other solvents to prepare a solution of different concentrations. Aim at the midthoracic plate of the bee and use a micro-droplet instrument to drip 1.0 μL of the test solution of each concentration. After the bee body is dried, it is transferred to the test cage and fed with 50% (mass concentration) sucrose water. Observe and record the poisoning symptoms and the number of deaths 24 hours and 48 hours after treatment. If the mortality rate of the control group is lower than 10%, if the difference in mortality rate after 24 hours and 48 hours of treatment reaches more than 10%, the observation time needs to be extended to a maximum of 96 hours. After the test, the data were statistically analyzed to calculate the half-lethal concentration (LC) 50 Values and 95% confidence limits.

[0061] (3) Limit test: Set the upper limit dose to 100 μg ai / bee. That is, if no bee mortality occurs when the test substance reaches 100 μg ai / bee, then there is no need to continue the test. If the solubility of the test substance is lower than 100 μg ai / bee, the maximum solubility is used as the upper limit concentration.

[0062] In the above technical solution, the step S3 refers to the national standard "Test Guidelines for Environmental Safety Assessment of Chemical Pesticides Part 12: Acute Toxicity Test for Fish" (GB / T 31270.12) and determines the acute toxicity data of the tested chemical control active ingredient to non-target fish in the aquatic environment (the recommended fish species is zebrafish Brachydanio rerio) by testing, which includes the following steps:

[0063] (1) Method selection: Select static test method, semi-static test method or flow test method according to the characteristics of the pesticide. When using static or semi-static test method, it should be ensured that the concentration of the test substance in the test solution is not less than 80% of the initial concentration during the test. If the concentration of the test substance in the test solution deviates by more than 20% during the flow test method, the actual concentration of the test substance in the test solution should be detected and the result calculated based on this, or the flow test method should be used to stabilize the concentration of the test substance in the test solution.

[0064] (2) Preliminary test: Under the conditions of the formal test, set five concentration groups with large intervals. Use five fish for each treatment, without replication. Observe and record the poisoning symptoms and mortality of the test fish for 96 hours (or 48 hours). The maximum total survival concentration and the minimum total lethal concentration for the test fish are determined through the preliminary test.

[0065] (3) Formal test: Within the concentration range determined in the preliminary test, set up 5 concentration groups at a certain proportional interval (the geometric difference should be controlled within 2.2 times), and set up a blank control group. If a solvent is used to assist dissolution, a solvent control group should be added. Each group should have 7 fish, without repetition, and ensure that the number of fish used in each group is the same. Observe and record the poisoning symptoms and death number of the test fish at any time within 6 hours after the start of the test. Thereafter, observe and record the poisoning symptoms and death number of the test fish at 24 hours, 48 hours, 72 hours and 96 hours. When there is no visible movement when the tail of the fish is touched with a glass rod, it is dead, and the dead fish should be removed in time. Measure and record the temperature, pH and dissolved oxygen of the test solution every day. After the test, perform mathematical statistics on the data and calculate the half-lethal concentration (LC) 50 Values and 95% confidence limits.

[0066] (4) Limit test: The upper effective concentration is set at 100 mg ai / L. That is, if the fish do not die when the test substance concentration reaches 100 mg ai / L, the test does not need to be continued. If the solubility of the test substance is less than 100 mg ai / L, its maximum solubility is used as the upper limit concentration.

[0067] In the above technical solution, the step S3 refers to the national standard "Chemical Pesticide Environmental Safety Assessment Test Guidelines Part 15: Earthworm Acute Toxicity Test" (GB / T 31270.15) and determines the acute toxicity data of the tested chemical control active ingredient to the non-target earthworm in the soil (Eisenia foetida is recommended) by testing, which includes the following steps:

[0068] (1) Preliminary test: According to the conditions of the formal test, set 5 groups of concentrations with large intervals, and find the lowest concentration of the test substance that is completely lethal to earthworms and the highest concentration that allows all earthworms to survive.

[0069] (2) Formal test: Set up 5 concentration groups within the concentration range determined in the preliminary test according to a certain difference, and set up a blank control group. If a solvent is used, a solvent control group should be added, and a blank control group without pesticide should be set up. Each concentration group should be repeated 3 times. Put 500g of soil in the specimen bottle, add the pesticide solution and mix thoroughly (if an organic solvent is used as a solvent, the organic solvent must be evaporated). Add appropriate amount of distilled water to adjust the soil moisture content to 30% to 35% of the soil dry weight. Put 10 earthworms in each treatment, tie the bottle mouth with gauze, and place the specimen bottle in an incubator at 20℃±2℃, humidity 70% to 90%, and light intensity 400lx to 800lx. The test lasted for two weeks. On the 7th and 14th days, pour out the soil in the bottle, observe and record the poisoning symptoms and death number of earthworms (touch the tail of the earthworm with a needle, if the earthworm does not respond, it is dead), and remove the dead earthworms in time. Based on the mortality rate of earthworms at 7 and 14 days, calculate the LC value of the pesticide's toxicity to earthworms. 50 Values and 95% confidence limits.

[0070] (3) Limit test: Set the upper limit concentration to 100 mg ai / dry soil. If no earthworms die, there is no need to continue the test.

[0071] In the above technical solution, the pests I and II in step S2 are respectively the Asian corn borer (Ostriniafurnacalis) and the fall armyworm (Spodoptera frugiperda).

[0072] In the above technical solution, the public database in step S3 is an international public pesticide database such as the e-Pesticide Manual (16th ed.), the North American Pesticide Action Network database PAN Pesticide Database, and the Pesticide Properties Database PPDB.

[0073] Compared with the prior art, the present invention has the following beneficial effects:

[0074] Compared with the selection of pesticides through the formal registration process, the present invention has the advantages of a short selection cycle and simpler and more effective screening of agents. At the same time, compared with the traditional emergency prevention and control method that only focuses on the control effect on a single target pest when selecting agents, the present invention has the advantage of "one drug for multiple protections" and takes into account the safety of major environmental non-target organisms (air birds, soil organisms earthworms, aquatic organisms fish and pollinating insects bees), thereby quickly screening out high-efficiency and low-toxic emergency prevention and control agent varieties. DETAILED DESCRIPTION

[0075] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0076] Example 1

[0077] Example 1 of the present invention provides a rapid initial screening and evaluation method for chemical control active ingredients for grassland borers, comprising the following steps:

[0078] Step S1: Conducting an indoor bioassay to evaluate the activity of chlorantraniliprole against the larvae of the meadow moth using the insect immersion method to obtain basic score data M. The score is classified according to Table 1:

[0079] Table 1 Basic score data M score division basis

[0080]

[0081] The indoor bioassay for evaluating the activity of the tested chemical control active ingredient against the larvae of the fall borer by the insect immersion method comprises the following steps:

[0082] (1) Material preparation: Meadow borer larvae were collected from alfalfa fields in Kangbao County, Hebei Province on June 10, 2023. Meadow borer larvae were reared on fresh ash vegetables (Chenopodium album L.) in an incubator at a temperature of 22.5-27.5°C, a relative humidity of 65-75%, and a photoperiod of L / D = 16h / 8h. The test was conducted after at least three generations of continuous rearing in the laboratory (during which they were not exposed to pesticides). Three-instar meadow borer larvae that were reared indoors, uniform in size, and healthy were selected for the test.

[0083] (2) Preparation: 95% chlorantraniliprole technical was dissolved in methanol and then diluted with water. Based on the preliminary test results of 0.1, 1, and 10 μg ai / L (with a geometric step of 10), five gradient concentrations (with a geometric step of 3) were set, including 0.037, 0.11, 0.33, 1.0, and 3.0 μg ai / L, for the formal test.

[0084] (3) Chemical treatment: After immersing the larvae in the chemical solution for 10 seconds, remove the excess solution with filter paper and transfer the larvae to normal conditions for rearing. Each treatment was repeated four times, with 10 larvae immersed in each replicate. A corresponding methanol treatment without chemical was also used as a control.

[0085] (4) Result investigation: The death of the grass moth larvae was investigated and recorded every 24 hours after the treatment. After the 72-hour test, the number of dead insects and the survival rate were statistically analyzed to calculate the half-lethal concentration (LC). 50 The value was 0.0818 μg ai / L and the 95% confidence limits were (0.0342-0.145), thus evaluating the stomach toxicity activity of the test agent 95% chlorantraniliprole against the larvae of S. frugiperda larvae as high, with a score of 85 points.

[0086] Step S2: Select two other farmland pests that occur at the same time as the fall armyworm: corn borer and fall armyworm, and evaluate the activity of chlorantraniliprole against them through indoor bioassays to obtain two bonus points, PI and PII, with a maximum of 10 points each. The bonus points PI and PII are scored according to Table 2:

[0087] Table 2: Basis for scoring bonus items

[0088]

[0089] The indoor bioassay for evaluating the activity of the tested chemical control active ingredient against pest I (Asian corn borer) and pest II (Spodoptera frugiperda) comprises the following steps:

[0090] (1) Material Preparation: Asian corn borer (O. corn borer) was collected from a corn field in Kangzhuang, Yanqing District, Beijing, on May 16, 2023, and fall armyworm (Spodoptera frugiperda) was collected from a corn field in Huadu District, Guangzhou, on May 1, 2023. Asian corn borer and fall armyworm larvae were reared on artificial diet in an incubator maintained at a temperature of 26-28°C, a relative humidity of 70%-80%, and a photoperiod of 16 h / 8 h. Three-instar Asian corn borer and fall armyworm larvae of uniform size and healthy growth reared indoors were selected for the experiments.

[0091] (2) Preparation of the agent: 95% chlorantraniliprole technical was dissolved in methanol and then diluted with water. Based on the preliminary test results of 1, 10, and 100 μg ai / L (geometric step of 10), five gradient concentrations (geometric step of 5) were set according to the geometric method, including 0.025, 0.125, 0.625, 3.125, and 15.625 μg ai / L, for the formal test on Asian corn borer. Based on the preliminary test results of 10, 100, and 1000 μg ai / L (geometric step of 10), five gradient concentrations (geometric step of 4) were set according to the geometric method, including 3.906, 15.625, 62.5, 250, and 1000 μg ai / L, for the formal test on fall armyworm.

[0092] (3) Chemical treatment: After immersing larvae of the Asian corn borer and fall armyworm in the chemical solution for 10 seconds, excess solution was removed with filter paper and the larvae were transferred to normal conditions for rearing. Each treatment was repeated four times, with 10 larvae immersed in each replicate. A corresponding methanol treatment without chemical was also used as a control.

[0093] (4) Result investigation: The death of Asian corn borer and fall armyworm larvae was recorded every 24 hours after treatment. After 72 hours of the test, the number of dead insects and the survival rate were statistically analyzed to calculate the half-lethal concentration (LC) of corn borer. 50 The value was 7.593 μg ai / L and the 95% confidence limit was (2.656~16.70); the LC50 of Spodoptera frugiperda was 0.05. 50 The value was 24.84 μg ai / L and the 95% confidence limit was (6.111-62.63). Finally, the stomach toxicity of the test agent 95% chlorantraniliprole to the larvae of Asian corn borer and fall armyworm was evaluated, and both had high activity, with a score of 7 points.

[0094] Step S3: Select environmental non-target organisms, including birds, bees, fish and earthworms, and query the acute toxicity data of chlorantraniliprole on environmental non-target organisms through the public database to obtain 6 deduction items: acute oral LD50 for birds 50 Value NI, acute feeding LC 50Value NⅡ, acute oral exposure to honey bees LD 50 (48h) value NⅢ, acute contact LD50 for bees 50 (48h) value NIV, LC for fish 50 (96h) value NV and LC value for earthworms 50 (14d) Value NVI, each item will be deducted up to 20 points. The deduction items are scored according to Tables 3.1 to 3.4:

[0095] Table 3.1 Basis for NI or NII score classification

[0096]

[0097] Table 3.2 Basis for NⅢ or NⅣ score division

[0098]

[0099] Table 3.3NⅤ score classification basis

[0100]

[0101]

[0102] Table 3.4NVI score classification basis

[0103]

[0104] After searching the public database e-Pesticide Manual (16th ed.) (Note: Since all toxicity data can be queried, there is no need to obtain the corresponding data through experiments), the acute oral toxicity LD50 of chlorantraniliprole to birds was obtained. 50 (mg ai / kg body weight) is >2250, low toxicity, score 0; short-term feeding toxicity LC for birds 50 (mg ai / kg 饲料 ) is >5620, low toxicity, score 0; acute oral toxicity to bees LD 50 (48h) (μg ai / bee) was >104.1, low toxicity, score 0; acute contact toxicity to bees LD50 50 (48h) (μg ai / bee) is >4, moderate to low toxicity, with a score of 0 to -5 (-5 is selected for conservatism); acute oral toxicity LC 50 (96h)(mg ai / L) was >13.8, low toxicity, score 0; acute oral toxicity LC 50 (14d)(mg ai / kg 干土 ) is >1000, low toxicity, and the score is 0.

[0105] Step S4: Calculate the comprehensive score S of the tested chemical control active ingredient according to the following formula:

[0106] S=M+PⅠ+PⅡ+NⅠ+NⅡ+NⅢ+NⅣ+NⅤ+NⅥ;

[0107] Specifically, S=85+7+7+0+0+0-5+0+0=94.

[0108] Step S5: Classify the levels according to Table 4 based on the comprehensive scores and give a recommended conclusion for the tested chemical control active ingredients;

[0109] Table 4 Comprehensive scoring classification basis

[0110] Recommended Conclusion S Strongly not recommended S≤50 Not recommended 50<S≤70 General Recommendations 70<S≤90 Recommended S>90.0

[0111] S=94>90.0, so the recommendation conclusion for chlorantraniliprole is "strongly recommended".

[0112] Example 2

[0113] Example 2 of the present invention provides a rapid initial screening and evaluation method for a chemical control active ingredient for grassland borer, which differs from Example 1 only in that the chemical control active ingredient to be tested is emamectin benzoate;

[0114] Example 3

[0115] Example 3 of the present invention provides a rapid initial screening and evaluation method for a chemical control active ingredient for meadow moth, which differs from Example 1 only in that the chemical control active ingredient to be tested is deltamethrin;

[0116] Example 4

[0117] Example 4 of the present invention proposes a rapid initial screening and evaluation method for a chemical control active ingredient for grassland borer, which differs from Example 1 only in that the chemical control active ingredient to be tested is methoxyfenozide;

[0118] The data obtained, scores and evaluation conclusions of each step of the evaluation method of Examples 1 to 4 are shown in Table 5:

[0119]

[0120]

[0121] The four application examples in Table 5 allow for rapid selection of the highly effective, low-toxic chlorantraniliprole for key recommendation. The highly effective but highly toxic emamectin benzoate and the low-toxic but low-efficiency methoxyfenozide are both not recommended. Of particular note, deltamethrin, a pyrethroid agent with high efficacy but high toxicity, is strongly not recommended. These recommendations are of great significance for agricultural extension departments in developing emergency control plans for meadow moths, guiding farmers in their use of emergency control agents, and simultaneously achieving multi-pronged prevention and control with a single agent while protecting the environment.

[0122] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A rapid initial screening and evaluation method for chemical control active ingredients of meadow moth, characterized in that: The following steps are involved: Step S1: Conducting an indoor bioassay to evaluate the activity of the tested chemical control active ingredient against the larvae of the meadow moth using the insect immersion method to obtain its basic score data M. The score is classified according to Table 1: Table 1 Basic score data M score division basis Step S2: Select two other farmland pests that occur at the same time as the meadow moth: Pest I and Pest II. Evaluate the activity of the tested chemical control active ingredient against them through indoor bioassays to obtain two bonus points, PⅠ and PⅡ, with a maximum of 10 points for each. The bonus points PⅠ and PⅡ are scored according to Table 2: Table 2: Basis for scoring bonus items Step S3: Select environmental non-target organisms, including birds, bees, fish and earthworms, and determine the acute toxicity data of the tested chemical control active ingredients on environmental non-target organisms through public database query or experimental measurement, and obtain 6 deduction items: acute oral toxicity LD50 to birds 50 Value NI, acute feeding toxicity LC for birds 50 Value NⅡ, acute oral toxicity to bees LD50 50 (48h) value NⅢ, acute contact toxicity to bees LD 50 (48h) value NIV, acute toxicity LC to fish 50 (96h) value NV and acute toxicity LC to earthworms 50 (14d) Value NVI, each item will be deducted up to 20 points. The deduction items are scored according to Tables 3.1 to 3.4: Table 3.1 Basis for NI or NII score classification Table 3.2 Basis for NⅢ or NⅣ score division Table 3.3NⅤ score classification basis Table 3.4NVI score classification basis Step S4: Calculate the comprehensive score S of the tested chemical control active ingredient according to the following formula: S=M+PⅠ+PⅡ+NⅠ+NⅡ+NⅢ+NⅣ+NⅤ+NⅥ; Step S5: Classify the levels according to Table 4 based on the comprehensive scores and give a recommended conclusion for the tested chemical control active ingredients; Table 4 Comprehensive scoring classification basis 。 2. The rapid initial screening and evaluation method for a chemical control active ingredient for grassland borer according to claim 1, characterized in that: In step S1, referring to the agricultural industry standard "Guidelines for Indoor Bioassay Tests of Pesticides - Insecticides Part 6: Insecticide Activity Test - Insect Dipping Method" (NY / T1154.6-2006), indoor bioassay evaluation of the activity of the tested chemical control active ingredient against the larvae of the grass borer is carried out by the insect dipping method, which includes the following steps: (1) Test material preparation: Three-instar larvae of the fern borer, which were raised indoors, uniform in size, and healthy, were selected for the test; (2) Preparation of reagents: Water-soluble reagents are directly dissolved in water, and other reagents are dissolved in appropriate organic solvents and then diluted with water; based on the results of the preliminary test, five series of mass concentrations are set according to the proportional method for formal testing; (3) Chemical treatment: After the larvae of the grass moth were immersed in the chemical solution for 10 seconds, the excess chemical solution was absorbed with filter paper and the larvae were transferred to normal conditions for rearing; each treatment was repeated 4 times, with 10 larvae immersed in each repetition, and the treatment with the corresponding organic solvent without chemical was set as a control; (4) Result investigation: The death of the grass moth larvae was investigated and recorded every 24 hours after the treatment. After the 72-hour test, the number of dead insects and the survival rate were statistically analyzed to calculate the half-lethal concentration (LC). 50 The values and 95% confidence limits were used to evaluate the stomach poison activity of the test agents against the larvae of S. frugiperda.

3. The rapid initial screening and evaluation method for a chemical control active ingredient for grassland borer according to claim 1, characterized in that: In step S2, referring to the agricultural industry standard "Guidelines for Indoor Bioassay Tests of Pesticides - Insecticides Part 6: Insecticide Activity Test - Insect Dipping Method" (NY / T1154.6), indoor bioassay evaluation of the activity of the tested chemical control active ingredient against pests I and II is carried out by the insect dipping method, which includes the following steps: (1) Test material preparation: Select healthy third-instar larvae of pests that have been reared indoors and are of uniform size; (2) Preparation of reagents: Water-soluble reagents are directly dissolved in water, and other reagents are dissolved in appropriate organic solvents and then diluted with water. Based on the results of the preliminary test, five series of mass concentrations are set according to the proportional method for formal testing; (3) Chemical treatment: After the target insects were immersed in the chemical solution for 10 seconds, the excess chemical solution was absorbed with filter paper and the test insects were transferred to normal conditions for rearing; each treatment was repeated 4 times, with 10 insects immersed in each repetition, and the corresponding organic solvent treatment without chemical was set as a control; (4) Result investigation: After treatment, the death of test insects was investigated and recorded every 24 hours. After the 72-hour test, the number of dead insects and the survival rate of test insects were statistically analyzed to calculate the half-lethal concentration (LC). 50 The values and 95% confidence limits were used to evaluate the stomach poison activity of the test agents against pests.

4. The rapid initial screening and evaluation method for a chemical control active ingredient for grassland borer according to claim 1, characterized in that: In step S3, referring to the national standard "Test Guidelines for Environmental Safety Evaluation of Chemical Pesticides Part 9: Acute Toxicity Test for Birds" (GB / T 31270.9), the acute toxicity data of the tested chemical control active ingredient to non-target birds in the air environment, namely Japanese quail Coturnix coturnix japonica, are determined by testing, including the following steps: a. Acute oral toxicity test steps (1) Preliminary test: According to the conditions of the formal test, set up 5 concentration groups with a large interval, and find the lowest lethal concentration and the highest survival concentration of the test substance for the test birds. Set the concentration of the formal test within this range; (2) Formal test: According to the concentration range determined in the preliminary test, 5 concentration groups are set at a certain interval, with 10 birds in each group, half of them are male and half are female. A blank control group is also set up. If solvent is used for solubilization, a solvent control group is also required. There are no replicates in the control group and each concentration group, and the concentration difference between concentration groups shall not exceed 2 times. The poisoning symptoms and deaths of the test birds are observed and recorded every 24 hours. After the test, the data are statistically analyzed to calculate the median lethal concentration (LD) 50 Values and 95% confidence limits; (3) Limit test: Based on the toxicity classification standard for pesticides to birds, the upper limit dose is set at 2000 mg ai / kg body weight. That is, if no bird dies when the test substance reaches 2000 mg ai / kg body weight, there is no need to continue the test; at this point, the oral toxicity of the test substance to birds can be determined to be low toxicity; b. Acute feeding toxicity test procedures (1) Preliminary test: According to the conditions of the formal test, set up five concentration groups with a large interval, and find the lowest total lethal concentration and the highest total survival concentration of the test substance for the test birds; within this range, set the concentration of the formal test; (2) Formal test: According to the concentration range determined in the preliminary test, 5 concentration groups are set at a certain interval, with 10 birds in each group, half of them are male and half are female. A blank control group is also set up. The blank control group is fed with normal feed. If solvent is used to assist solubilization, a solvent control group is also required. There are no replicates in the control group and each concentration group. The concentration difference between the concentration groups shall not exceed 2 times. The poisoning symptoms and deaths of the experimental birds are observed and recorded every 24 hours. After the test, the data are statistically analyzed to calculate the half-lethal concentration (LC) 50 Values and 95% confidence limits; (3) Limit test: According to the classification standard of pesticide toxicity to birds, the upper limit dose is set at 5000 mg ai / kg feed. That is, if no bird deaths occur when the test substance reaches 5000 mg ai / kg feed, there is no need to continue the test; at this time, it can be determined that the test substance has low feeding toxicity to birds.

5. The rapid initial screening and evaluation method for a chemical control active ingredient for grassland borer according to claim 1, characterized in that: In step S3, referring to the national standard "Test Guidelines for Environmental Safety Assessment of Chemical Pesticides Part 10: Acute Toxicity Test for Bees" (GB / T 31270.10), the acute toxicity data of the tested chemical control active ingredient to the non-target organism bee in the plant pollination environment, the Italian adult worker bee Apis mellifera L., are determined by testing, including the following steps: a. Acute oral toxicity test steps (1) Preliminary test: According to the conditions of the formal test, five dose groups are set with a large interval. The minimum lethal dose and the maximum survivable dose of the test bees are determined through the preliminary test; (2) Formal test: According to the concentration range determined in the preliminary test, 5 dosage groups were set up with a certain proportional interval (the geometric difference should be controlled within 2.2), with 10 bees in each group, and a blank control group was set up. If organic solvents were used for solubilization, a solvent control group was also required. The bees in the storage cage were introduced into the test cage, and then 100 μL of 50% mass concentration sucrose water bath containing different concentrations of the test substance was added to the feeder, and the consumption of the drug solution for each group was measured. Once the drug solution was consumed, the food container was removed and replaced with sucrose water without the test substance for feeding (unlimited). For some test substances, If the bees refuse to eat at a higher test dose, resulting in little or no food consumption, the observation time shall be extended to 6 hours at most, and the food consumption shall be measured (i.e., the volume or weight of the remaining food in the treatment shall be measured). There shall be 3 replicates for the control group and each treatment group; the poisoning symptoms and the number of deaths shall be observed and recorded 24 hours and 48 hours after the treatment; if the mortality rate of the control group is lower than 10%, if the difference in mortality rate after 24 hours and 48 hours of treatment reaches 10%, the observation time shall be extended to 96 hours at most; after the end of the test, the data shall be statistically analyzed to calculate the half-lethal concentration (LC50) 50 Values and 95% confidence limits; (3) Limit test: Set the upper limit dose at 100 μg ai / bee. That is, if no bee death occurs when the test substance reaches 100 μg ai / bee, there is no need to continue the test; if the solubility of the test substance is lower than 100 μg ai / bee, the maximum solubility is used as the upper limit concentration; b. Acute contact toxicity test steps (1) Preliminary test: According to the conditions of the formal test, five dose groups are set with a large interval. The minimum lethal dose and the maximum survivable dose of the test bees are determined through the preliminary test; (2) Formal test: According to the concentration range determined in the preliminary test, 5 dosage groups were set up with a certain proportional interval (the geometric difference should be controlled within 2.2), with 10 bees in each group, and a blank control group and a solvent control group were set up; the control group and each treatment group were set up with 3 replicates; the test substance was dissolved in methanol solvent and prepared into drug solutions of different concentrations; 1.0 μL of the test solution of each concentration was dripped on the mesothorax of the bees using a micro-drip meter, and after the bees were dried, they were transferred to the test cage and fed with 50% mass concentration sucrose water; the poisoning symptoms and the number of deaths were observed and recorded 24 hours and 48 hours after treatment; if the mortality rate of the control group was lower than 10%, if the difference in mortality rate after 24 hours and 48 hours of treatment reached 10%, the observation time should be extended to a maximum of 96 hours; after the end of the test, the data were statistically analyzed to calculate the half lethal concentration (LC) 50 Values and 95% confidence limits; (3) Limit test: The upper limit dose is set at 100 μg ai / bee. That is, if no bee death occurs when the test substance reaches 100 μg ai / bee, there is no need to continue the test; if the solubility of the test substance is lower than 100 μg ai / bee, the maximum solubility is used as the upper limit concentration.

6. The rapid initial screening and evaluation method for a chemical control active ingredient for grassland borer according to claim 1, characterized in that: In step S3, referring to the national standard "Test Guidelines for Environmental Safety Assessment of Chemical Pesticides Part 12: Acute Toxicity Test for Fish" (GB / T 31270.12), the acute toxicity data of the tested chemical control active ingredient to the non-target fish species in the aquatic environment, namely, zebrafish Brachydanio rerio, are determined by testing, including the following steps: (1) Method selection: static test method, semi-static test method or flow test method should be selected according to the characteristics of the pesticide. When using static or semi-static test method, it should be ensured that the concentration of the test substance in the test solution is not less than 80% of the initial concentration during the test. If the concentration of the test substance in the test solution deviates by more than 20% during the test of the flow test method, the actual concentration of the test substance in the test solution should be detected and the result calculated based on it, or the flow test method should be used to stabilize the concentration of the test substance in the test solution. (2) Preliminary test: According to the conditions of the formal test, set 5 concentration groups with large intervals; use 5 fish for each treatment without replication, observe and record the poisoning symptoms and mortality of the test fish for 96 hours (or 48 hours); determine the maximum total survival concentration and the minimum total lethal concentration of the test fish through the preliminary test; (3) Formal test: Within the concentration range determined in the preliminary test, set up 5 concentration groups at a certain proportional interval (the geometric difference should be controlled within 2.2 times), and set up a blank control group. If solvent dissolution is used, a solvent control group should be added. Each group should have 7 fish, without repetition, and ensure that the number of fish used in each group is the same. Observe and record the poisoning symptoms and death number of the test fish at any time within 6 hours after the start of the test. Thereafter, observe and record the poisoning symptoms and death number of the test fish at 24 hours, 48 hours, 72 hours and 96 hours. When there is no visible movement when the tail of the fish is touched with a glass rod, it is dead, and the dead fish should be removed in time; measure and record the temperature, pH and dissolved oxygen of the test solution every day; after the end of the test, perform mathematical statistics on the data and calculate the half-lethal concentration (LC) 50 Values and 95% confidence limits; (4) Limit test: The upper effective concentration is set at 100 mg ai / L. That is, if the fish do not die when the test substance concentration reaches 100 mg ai / L, there is no need to continue the test. If the solubility of the test substance is less than 100 mg ai / L, its maximum solubility is used as the upper limit concentration.

7. The rapid initial screening and evaluation method for a chemical control active ingredient for grassland borer according to claim 1, characterized in that: In step S3, referring to the national standard "Test Guidelines for Environmental Safety Assessment of Chemical Pesticides Part 15: Acute Toxicity Test for Earthworms" (GB / T 31270.15), the acute toxicity data of the tested chemical control active ingredient to the non-target earthworm Eisenia foetida in the soil are determined by testing, including the following steps: (1) Preliminary test: According to the conditions of the formal test, set five concentration groups with large intervals, and find the lowest concentration of the test substance that is completely lethal to earthworms and the highest concentration that allows complete survival; (2) Formal test: Set up 5 concentration groups according to a certain level difference within the concentration range determined in the preliminary test, and set up a blank control group. If a solvent is used, a solvent control group should be added, and a blank control group without pesticide should be set up. Each concentration group should be repeated 3 times. Put 500g of soil in a specimen bottle, add the pesticide solution and mix it thoroughly (if an organic solvent is used as a solvent, the organic solvent must be evaporated). Add appropriate amount of distilled water to adjust the soil moisture content to 30% to 35% of the soil dry weight. Put 10 earthworms in each treatment, tie the bottle mouth with gauze, and place the specimen bottle in an incubator at 20℃±2℃, humidity 70% to 90%, and light intensity 400 1x to 800lx. The test lasts for two weeks. Pour out the soil in the bottle on the 7th and 14th day, observe and record the poisoning symptoms and death number of earthworms (touch the tail of the earthworm with a needle, if the earthworm does not respond, it is dead), and remove the dead earthworms in time. Based on the mortality rate of earthworms at 7 and 14 days, calculate the LC value of the pesticide's toxicity to earthworms. 50 Values and 95% confidence limits; (3) Limit test: Set the upper limit concentration to 100 mg ai / dry soil. If no earthworms die, there is no need to continue the test.

8. The rapid initial screening and evaluation method for a chemical control active ingredient for grassland borer according to claim 1, characterized in that: In step S2, pests I and II are respectively Asian corn borer (Ostrinia furnacalis) and fall armyworm (Spodoptera frugiperda).

9. The rapid initial screening and evaluation method for chemical control active ingredients of meadow moth according to claim 1, characterized in that: The public database in step S3 is the e-Pesticide Manual (16th ed.), the North American Pesticide Action Network database PAN Pesticide Database or the Pesticide Properties Database PPDB (Pesticide Properties Database).

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