Nicotine herbicide as well as formula optimization method and application thereof

Abstract

The invention provides a nicotine herbicide and a formula optimization method and application thereof, and belongs to the technical field of herbicides, the effective component of the nicotine herbicide is nicotine, and the mass concentration of the nicotine is 0.30-0.60%. Nicotine in the herbicide can be replaced by a dry tobacco leaf extract, and a preparation method of the dry tobacco leaf extract comprises the following steps: grinding dry tobacco leaves into powder, sieving, adding water, dissolving, and filtering to obtain the dry tobacco leaf extract. The herbicide can be prepared into any dosage form suitable for agricultural use by a known method, and the dosage form comprises a soluble concentrate, a fogging concentrate and the like. When the pesticide is applied to crop production, crop plant phytotoxicity and pesticide residues cannot be caused to crops; particularly, during tobacco production, nicotine is used as an endogenous component of tobacco, so that no herbicide residue is caused to tobacco leaves; the problems that an existing herbicide for the tobacco field causes crop plant phytotoxicity and crop pesticide residues exceed the standard are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of herbicides, and in particular, relates to a nicotine herbicide, a formulation optimization method and an application thereof. Background Art

[0002] At present, the weed control of crops in my country mainly relies on chemical reagents, such as glyphosate, paraquat, cypermethrin, 40% cypermethrin·isoxazone EC, isopropylamine and isopropylamine. Due to the pollution problems, serious poisoning hazards and limited treatment methods of glyphosate, paraquat and other lethal herbicides, they are restricted by the Ministry of Agriculture and Rural Affairs. After that, many new herbicide products have been launched to fill the market gap. New herbicides are also chemical reagents. During use, it is easy to cause excessive application or improper application. At the same time, under the combined effects of factors such as the physical and chemical properties of the pesticides themselves and changes in the field environment, it is easy to cause problems such as crop plant damage and excessive pesticide residues in crops. The continuous excessive use of chemical reagent herbicides will also have many negative impacts on the ecological environment and human health. Its selective effect on weeds will also change the weed community in the field, enhance the resistance of some weeds, and expand the spectrum of weed resistance. The difficulty in developing new herbicides has long been an important factor that has plagued the development of herbicides in my country. Therefore, the development of economical, safe, and environmentally friendly crop herbicides that are highly efficient, low-toxic, low-residue or residue-free to replace chemical herbicides is of great significance to promoting the sustainable development of agriculture. Summary of the invention

[0003] In view of this, the present invention provides a nicotine herbicide and a method and application of its formulation optimization, which can solve the problems of crop plant damage and excessive pesticide residues in crops caused by the use of herbicides in existing tobacco fields.

[0004] The present invention is achieved in that:

[0005] A first aspect of the present invention provides a nicotine herbicide, wherein the active ingredient of the nicotine herbicide is nicotine, and the mass concentration of nicotine is 0.30-0.60%.

[0006] On the basis of the above technical solution, a nicotine herbicide of the present invention can also be improved as follows:

[0007] Wherein, the nicotine mass concentration of the herbicide is 0.30-0.45%.

[0008] Preferably, the nicotine herbicide may be a nicotine aqueous solution.

[0009] Furthermore, the nicotine in the herbicide is replaced by a dry tobacco leaf extract, and the preparation method of the dry tobacco leaf extract is: grinding the dry tobacco leaves, sieving, adding water to dissolve, and filtering to obtain the dry tobacco leaf extract. Preferably, the filtration is performed using filter paper. More preferably, the dry tobacco leaves are ground and sieved through a 30-60 mesh sieve, 5-20 mL of water is added to each 1 g of powder to dissolve, and the dry tobacco leaf extract is obtained by filtering with filter paper. Most preferably, the dry tobacco leaves are ground and sieved through a 40 mesh sieve, 10 mL of water is added to each 1 g of powder to dissolve, and the dry tobacco leaf extract is obtained by filtering with filter paper.

[0010] The herbicide may comprise or consist of the above-mentioned dried tobacco leaf extract.

[0011] Furthermore, the herbicide is in the form of a soluble solution or a spray.

[0012] A second aspect of the present invention provides a method for optimizing the formulation of a nicotine herbicide, comprising the following steps:

[0013] Step 1, preparing nicotine aqueous solutions of different concentrations, the concentration range is 0.15%-0.60%;

[0014] Step 2, using the prepared nicotine aqueous solution in a mixed weed control test and a tobacco field weed control test;

[0015] Step 3: In the mixed weed control test, each concentration of nicotine aqueous solution was sprayed, and the unit spraying amount was 100mL / m 2 , after 10 days, the plant protection effect and fresh weight protection effect were determined;

[0016] Step 4: In the weed control test in tobacco fields, 10 days after tobacco transplanting, each concentration of nicotine aqueous solution was sprayed, and the unit spraying amount was 100mL / m 2 , after 10 days, the plant protection effect and fresh weight protection effect were determined;

[0017] Step 5, comparing the weed control effects of nicotine aqueous solutions of different concentrations in a mixed weed control test and a tobacco field weed control test, and comparing the weed control effects with those of 50% naproxen wettable powder;

[0018] Step 6: Comprehensively consider the weed control effect and the economic cost of nicotine dosage to determine the optimal concentration range of nicotine herbicide.

[0019] On the basis of the above technical solution, the formulation optimization method of a nicotine herbicide of the present invention can also be improved as follows:

[0020] Furthermore, the plant protection effect calculation formula is: plant protection effect (percentage) = (the number of weeds in the blank control area minus the number of weeds remaining in the treatment area) divided by the number of weeds in the blank control area multiplied by 100; the fresh weight protection effect calculation formula is: fresh weight protection effect (percentage) = (the fresh weight of weeds in the blank control area minus the fresh weight of weeds remaining in the treatment area) divided by the fresh weight of weeds in the blank control area multiplied by 100, wherein the blank control area is treated by spraying water.

[0021] The third aspect of the present invention provides an application of a nicotine herbicide, wherein the active ingredient of the nicotine herbicide is nicotine, and the nicotine herbicide is used as a weed killer, preferably as a weed killer in tobacco fields, and more preferably, the nicotine herbicide is a nicotine aqueous solution.

[0022] Preferably, the mass concentration of nicotine in the nicotine herbicide is 0.30-0.60%, more preferably 0.30-0.45%.

[0023] Preferably, the nicotine herbicide comprises or consists of a dry tobacco leaf extract. The preparation method of the dry tobacco leaf extract is: grinding the dry tobacco leaves, sieving, adding water to dissolve, and filtering to obtain the dry tobacco leaf extract, preferably, using filter paper for the filtration, more preferably, grinding the dry tobacco leaves and passing through a 30-60 mesh sieve, adding 5-20 mL of water to each 1 g of powder to dissolve, and filtering with filter paper to obtain the dry tobacco leaf extract, most preferably, grinding the dry tobacco leaves and passing through a 40 mesh sieve, adding 10 mL of water to each 1 g of powder to dissolve, and filtering with filter paper to obtain the dry tobacco leaf extract.

[0024] Preferably, the nicotine herbicide is used as an aqueous nicotine solution as a herbicide for weeds in tobacco fields.

[0025] The weeds may be one or more selected from crabgrass, foxtail grass, amaranth and quinoa.

[0026] On the basis of the above technical solution, the application of a nicotine herbicide of the present invention can also be improved as follows:

[0027] Furthermore, when the nicotine aqueous solution is used as a herbicide for weeds in tobacco fields, the step of determining optimal herbicide application parameters is also included, specifically including:

[0028] S10, obtaining multiple groups of historical data, specifically weed control effect data of nicotine herbicides using nicotine aqueous solutions of different concentrations under different application parameters, wherein the application parameters include application amount, application time, and continuous application days;

[0029] S20, establishing and fitting a weed control effect equation group according to the multiple groups of historical data;

[0030] S30, using the weed control effect equation group, constructing a multi-objective optimization model to maximize the weed mortality rate and weed growth inhibition rate while minimizing the application amount, continuous application days and economic cost;

[0031] S40, using a genetic algorithm or a particle swarm optimization algorithm to solve a multi-objective optimization model to obtain optimal herbicide application parameters, including an optimal concentration, an optimal application amount, an optimal application time, and an optimal number of continuous application days;

[0032] S50. Based on the obtained optimal application parameters, an application test of the nicotine herbicide is conducted in an actual field to verify the weed control effect and make necessary adjustments, and finally determine the optimal application plan of the nicotine herbicide.

[0033] Furthermore, the weed control effect equation group includes a weed mortality rate equation, a weed growth inhibition rate equation, a weed regeneration inhibition rate equation, a weed plant height change equation, and a weed leaf area index change equation.

[0034] Furthermore, the weed control effect data include weed mortality rate, weed growth inhibition rate, weed regeneration inhibition rate, weed plant height change, and weed leaf area index change.

[0035] Compared with the prior art, the nicotine herbicide and its formulation optimization method and application provided by the present invention have the following beneficial effects: nicotine, the main active ingredient of the nicotine herbicide, is an endogenous active substance of the plant, and its application in crop production will not cause crop plant damage and pesticide residues to the crops themselves; especially in tobacco production, nicotine, as an endogenous component of tobacco, will not cause any herbicide residues to tobacco leaves; and the problem of existing herbicides used in tobacco fields causing crop plant damage and excessive crop pesticide residues is solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a comparison chart of the nicotine sensitivity test of tobacco seedlings in Example 1.

[0037] Figure 2 This is a comparison chart of the weed control effect of pure nicotine in Example 1.

[0038] Figure 3 This is a comparison chart of the herbicidal effects of the dry tobacco leaf extract in Example 3.

[0039] Figure 4 Flow chart of the steps of determining optimal herbicide application parameters in the third aspect of the present invention.

[0040] Figure 5 The graph is a relationship between the weed mortality rate and the herbicide concentration and application rate in Example 5.

[0041] Figure 6This is a diagram showing the control effects of the main weed species in Example 5.

[0042] Figure 7 This is a graph showing the change of weed growth indicators over time in Example 5.

[0043] Figure 8 This is a comparison chart of tobacco yield and quality in Example 5.

[0044] Fig. 9 This is a cost-benefit analysis diagram in Example 5. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0046] A first aspect of the present invention provides a nicotine herbicide, wherein the active ingredient of the herbicide is nicotine, and the mass concentration of nicotine is 0.30-0.60%.

[0047] On the basis of the above technical solution, a nicotine herbicide of the present invention can also be improved as follows:

[0048] Wherein, the nicotine mass concentration of the herbicide is 0.30-0.45%.

[0049] Preferably, the nicotine herbicide may be a nicotine aqueous solution.

[0050] Furthermore, the nicotine in the herbicide is replaced by a dry tobacco leaf extract, and the preparation method of the dry tobacco leaf extract is: grinding the dry tobacco leaves, sieving, adding water to dissolve, and filtering to obtain the dry tobacco leaf extract. Preferably, the filtration is performed using filter paper. More preferably, the dry tobacco leaves are ground and sieved through a 30-60 mesh sieve, 5-20 mL of water is added to each 1 g of powder to dissolve, and the dry tobacco leaf extract is obtained by filtering with filter paper. Most preferably, the dry tobacco leaves are ground and sieved through a 40 mesh sieve, 10 mL of water is added to each 1 g of powder to dissolve, and the dry tobacco leaf extract is obtained by filtering with filter paper.

[0051] The herbicide may comprise or consist of a dried tobacco leaf extract.

[0052] Furthermore, the herbicide is in the form of a soluble solution or a spray.

[0053] Four specific embodiments of the first aspect of the present invention are provided below:

[0054] Example 1: Test on the weed control effect of pure nicotine

[0055] The nicotine herbicides in this Example 1 are nicotine aqueous solutions with mass concentrations of 0.15%, 0.30%, 0.45% and 0.60%, respectively.

[0056] Treatment group 1 (nicotine herbicide): nicotine aqueous solution was sprayed on mixed weeds (unit spraying rate 100mL / m 2 ), avoid tobacco seedlings when spraying, and calculate the plant protection effect (plant protection effect (%) = (number of weeds in blank control area - number of remaining weeds in treatment area) / number of weeds in blank control area × 100) and fresh weight protection effect (fresh weight protection effect (%) = (fresh weight of weeds in blank control area - fresh weight of remaining weeds in treatment area) / fresh weight of weeds in blank control area × 100) after 10 days. The blank control used was the water spraying treatment.

[0057] Treatment group 2 (chemical herbicide): Use purchased 50% naproxen wettable powder, 100g-150g / mu, dilute with about 50L of water, and spray on mixed weeds (unit spraying amount 100mL / m 2 ), avoid tobacco seedlings when spraying, and calculate the plant protection effect and fresh weight protection effect after 10 days. The specific formula refers to treatment group 1.

[0058] Figure 2 The graph shows the comparison of the weed control effect after applying the nicotine herbicide and the blank control (water). The results obtained in the weed control effect test of the nicotine herbicide and the chemical herbicide on mixed weeds in Example 1 are listed in the following Table 1.

[0059] Table 1: Control effect of nicotine herbicides on mixed weeds

[0060]

[0061] The above test results show that nicotine herbicide with 0.30% nicotine content can achieve the same weed control effect as 50% naproxen wettable powder; the effects of 0.45% and 0.60% nicotine herbicides are higher than 50% naproxen wettable powder, and the weed control effect increases with the increase of nicotine content. Figure 1 It can be seen that 0.2% nicotine can kill the newly sprouted tobacco seedlings. Taking into account the weed control effect and the economic cost of nicotine dosage, the appropriate nicotine content of nicotine herbicide is 0.30-0.45%.

[0062] Example 2: Field weed control application of pure nicotine

[0063] The nicotine herbicides in Example 2 are nicotine aqueous solutions with mass concentrations of 0.15%, 0.30%, 0.45% and 0.60%, respectively.

[0064] Treatment group 1 (nicotine herbicide): 10 days after the tobacco was transplanted to the tobacco field, the nicotine aqueous solution was evenly sprayed on the surface of the seedling belt (unit spraying amount 100mL / m 2 ), avoid tobacco seedlings during spraying, and calculate the plant protection effect and fresh weight protection effect after 10 days. The specific formula refers to Example 1, and the blank control used is the water spray treatment.

[0065] Treatment group 2 (chemical herbicide): 10 days after tobacco transplanting, use the purchased 50% naproxen WP at 100g-150g / mu, dilute with about 50L of water and mix thoroughly, and spray evenly on the surface of the seedling belt (unit spraying amount 100mL / m 2 ), avoid tobacco seedlings when spraying, and calculate the plant protection effect and fresh weight protection effect after 10 days. The specific formula refers to treatment group 1.

[0066] This Example 2 is a test of the weed control effect of nicotine herbicides and chemical herbicides in tobacco fields. The results obtained are listed in the following Table 2.

[0067] The tobacco used for the test was Zhongyan 100, and the test site was in the tobacco field of Shimen Village, Jimo District, Qingdao City, Shandong Province. The test day (i.e. the spraying treatment day) was sunny, and the temperature on the test day was 24° C. The test results are listed in Table 2 below.

[0068] Table 2: Field weed control test results of nicotine herbicides

[0069]

[0070] The above test results show that nicotine herbicide with 0.30% nicotine content can achieve the same weed control effect as 50% naproxen wettable powder; the weed control ability increases with the increase of nicotine content. Considering the weed control effect and nicotine dosage cost, the appropriate nicotine content of nicotine herbicide is 0.30-0.45%.

[0071] Example 3: Test on the weed control effect of dried tobacco leaf extract

[0072] In this embodiment 3, the nicotine herbicide is a dry tobacco leaf extract.

[0073] The preparation method of the dry tobacco leaf extract in this Example 3 is: grind the dry tobacco leaves into powder and pass it through a 40-mesh sieve; add 10 mL of water to dissolve every 1 g of powder, and filter it with filter paper to obtain the dry tobacco leaf extract.

[0074] After testing, the nicotine content of the dry tobacco leaf extract is about 0.37%.

[0075] Treatment group 1 (dry tobacco leaf extract): The mixed weeds were sprayed with the above dry tobacco leaf extract (unit spraying rate 100mL / m 2), avoid tobacco seedlings during spraying, and calculate the plant protection effect and fresh weight protection effect after 10 days. The specific calculation formula refers to Example 1. The water spraying treatment was used as a blank control.

[0076] Treatment group 2 (nicotine herbicide): a nicotine aqueous solution with a nicotine content of 0.30% was used to spray the mixed weeds (unit spraying amount 100mL / m 2 ), avoid tobacco seedlings during spraying, and calculate the plant protection effect and fresh weight protection effect after 10 days. The specific calculation formula refers to treatment group 1.

[0077] Treatment group 3 (chemical herbicide): Use purchased 50% naproxen wettable powder, 100g-150g / mu, dilute with about 50L of water, and spray on mixed weeds (unit spraying amount 100mL / m 2 ), avoid tobacco seedlings when spraying, and calculate the plant protection effect and fresh weight protection effect after 10 days. The specific formula refers to treatment group 1.

[0078] Figure 3 The following table shows the results of the weed control effect test of the nicotine herbicide, the dry tobacco leaf extract and the chemical herbicide on mixed weeds.

[0079] Table 3: Control effect of dry tobacco leaf extract on mixed weeds

[0080]

[0081] Comparing the above examples, the weed control effects of nicotine herbicide and dry tobacco leaf extract are relatively consistent, and are comparable to the weed control effect of 50% naproxen wettable powder. The above results show that the extract of dry tobacco leaves can also be used for field weed control.

[0082] Example 4: Field weed control application of dried tobacco leaf extract

[0083] In this embodiment 4, the nicotine herbicide is a dry tobacco leaf extract.

[0084] The preparation method of the dry tobacco leaf extract in Example 4 is as follows: grind the dry tobacco leaves into powder and pass it through a 40-mesh sieve; add 10 mL of water to dissolve every 1 g of powder, and filter with filter paper to obtain the dry tobacco leaf extract.

[0085] After testing, the nicotine content of the dry tobacco leaf extract is about 0.37%.

[0086] Treatment group 1 (dry tobacco leaf extract): 10 days after the tobacco was transplanted to the tobacco field, the dry tobacco leaf extract was evenly sprayed on the surface of the seedling belt (unit spraying amount 100mL / m 2), avoid tobacco seedlings during spraying, and calculate the plant protection effect and fresh weight protection effect after 10 days. The specific formula is shown in Example 1. Observe the changes of tobacco seedlings before and after spraying dry tobacco leaf extract. The water spraying treatment is used as a blank control in the test.

[0087] Treatment group 2 (nicotine herbicide): 10 days after the tobacco was transplanted to the tobacco field, a nicotine aqueous solution with a nicotine content of 0.30% was evenly sprayed on the surface of the seedling belt (unit spraying amount 100mL / m 2 ), avoid tobacco seedlings during spraying, and calculate the plant protection effect and fresh weight protection effect 10 days later. The specific formula refers to treatment group 1. Observe the changes of tobacco seedlings before and after spraying dry tobacco leaf extract.

[0088] Treatment group 3 (chemical herbicide): 10 days after the tobacco was transplanted to the tobacco field, 50% naproxenic acid wettable powder was purchased and diluted with about 50L of water at a rate of 100g-150g / mu and sprayed on the mixed weeds (unit spraying amount 100mL / m 2 ), avoid tobacco seedlings during spraying, and calculate the plant protection effect and fresh weight protection effect 10 days later. The specific formula refers to treatment group 1. Observe the changes of tobacco seedlings before and after spraying dry tobacco leaf extract.

[0089] The tobacco used for the test was Zhongyan 100, and the test site was in the tobacco field of Shimen Village, Jimo District, Qingdao City, Shandong Province. The test day (i.e. the spraying treatment day) was sunny, and the temperature on the test day was 23°C. The test results are listed in Table 4.

[0090] Table 4: Field weed control effect of dry tobacco leaf extract

[0091]

[0092]

[0093] Comparing the above examples, the weed control effects of nicotine herbicide and dry tobacco leaf extract are relatively consistent, and are comparable to the weed control effect of 50% naproxen wettable powder. The above results show that dry tobacco leaf extract has a good effect in field weed control.

[0094] The above test results show that nicotine herbicide has a weed control effect comparable to that of 50% pyrimethamine wettable powder in the field. At the same time, nicotine herbicide also has the following advantages: nicotine, the main active ingredient of nicotine herbicide, is an endogenous active substance of plants, and its application in crop production will not cause pesticide residues to the crops themselves; especially in tobacco production, nicotine, as an endogenous component of tobacco, will not cause any herbicide residues to tobacco leaves; and tobacco leaves that are easily available in the tobacco production process can be used as raw materials to prepare tobacco leaf extracts, which can be used as nicotine herbicides, which helps to reduce production costs.

[0095] A second aspect of the present invention provides a method for optimizing the formulation of a nicotine herbicide, comprising the following steps:

[0096] Step 1, preparing nicotine aqueous solutions of different concentrations, the concentration range is 0.15%-0.60%;

[0097] Step 2, using the prepared nicotine aqueous solution in a mixed weed control test and a tobacco field weed control test;

[0098] Step 3: In the mixed weed control test, each concentration of nicotine aqueous solution was sprayed, and the unit spraying amount was 100mL / m 2 , after 10 days, the plant protection effect and fresh weight protection effect were determined;

[0099] Step 4: In the weed control test in tobacco fields, 10 days after tobacco transplanting, each concentration of nicotine aqueous solution was sprayed, and the unit spraying amount was 100mL / m 2 , after 10 days, the plant protection effect and fresh weight protection effect were determined;

[0100] Step 5, comparing the weed control effects of nicotine aqueous solutions of different concentrations in a mixed weed control test and a tobacco field weed control test, and comparing the weed control effects with those of 50% naproxen wettable powder;

[0101] Step 6: Comprehensively consider the weed control effect and the economic cost of nicotine dosage to determine the optimal concentration range of nicotine herbicide.

[0102] On the basis of the above technical solution, the formulation optimization method of a nicotine herbicide of the present invention can also be improved as follows:

[0103] Furthermore, the plant protection effect calculation formula is: plant protection effect (percentage) = (the number of weeds in the blank control area minus the number of weeds remaining in the treatment area) divided by the number of weeds in the blank control area multiplied by 100; the fresh weight protection effect calculation formula is: fresh weight protection effect (percentage) = (the fresh weight of weeds in the blank control area minus the fresh weight of weeds remaining in the treatment area) divided by the fresh weight of weeds in the blank control area multiplied by 100, wherein the blank control area is treated by spraying water.

[0104] The third aspect of the present invention provides an application of a nicotine herbicide, wherein the aqueous solution of the specific nicotine herbicide is used as a herbicide for weeds in tobacco fields. Specifically, the nicotine herbicide used in the present invention can be divided into two application methods according to the needs of crop planting: pre-emergence closed weeding and post-emergence weeding. When performing pre-emergence closed weeding, the herbicide can be fully shaken and evenly sprayed on the soil surface of the ridge 5 days before sowing or transplanting seedlings, and the unearthed weeds are killed, and then sowing or transplanting seedlings are performed; when performing post-emergence weeding, the herbicide is evenly sprayed on the surface of the seedling belt 5 days after the crop seedlings or transplanting seedlings, avoiding the unearthed or transplanted seedlings during spraying, and the unearthed weeds are killed. The best time to apply the herbicide in the field is between 10 am and 4 pm on a sunny day. During this period, the temperature is moderate and the humidity is high, which is conducive to the attachment and absorption of the herbicide and can give full play to the efficacy of the herbicide.

[0105] On the basis of the above technical solution, the application of a nicotine herbicide of the present invention can also be improved as follows:

[0106] Furthermore, when the nicotine aqueous solution is used as a herbicide for weeds in tobacco fields, the step of determining optimal herbicide application parameters is also included, specifically including:

[0107] S10, acquiring multiple groups of historical data, specifically weed control effect data of nicotine herbicides using nicotine aqueous solutions of different concentrations under different application parameters, the application parameters including application amount, application time, and continuous application days, the weed control effect data including weed mortality rate, weed growth inhibition rate, weed regeneration inhibition rate, weed plant height change, and weed leaf area index change;

[0108] S20, establishing and fitting a set of weed control effect equations based on the multiple sets of historical data, including a weed mortality rate equation, a weed growth inhibition rate equation, a weed regeneration inhibition rate equation, a weed height change equation, and a weed leaf area index change equation;

[0109] S30, using the weed control effect equation group, constructing a multi-objective optimization model to maximize the weed mortality rate and weed growth inhibition rate while minimizing the application amount, continuous application days and economic cost;

[0110] S40, using a genetic algorithm or a particle swarm optimization algorithm to solve a multi-objective optimization model to obtain optimal herbicide application parameters, including an optimal concentration, an optimal application amount, an optimal application time, and an optimal number of continuous application days;

[0111] S50. Based on the obtained optimal application parameters, an application test of the nicotine herbicide is conducted in an actual field to verify the weed control effect and make necessary adjustments, and finally determine the optimal application plan of the nicotine herbicide.

[0112] Each equation in the weed control effect equation group involved in the present invention is obtained by fitting. First, as many different relationships as possible are listed in the equation group, and then all the relationships are fitted to obtain weights, and finally each equation is obtained.

[0113] The weed mortality equation is specifically expressed as follows:

[0114] D=β0+β1C+β2A+β3T+β4D t +β5C 2 +β6A 2 +β7T 2 +β8D t 2 +β9CA+β 10 CT+β 11 CD t +ε;

[0115] Where D is the weed mortality rate (%); C is the herbicide concentration (g / L); A is the application amount (L / ha); T is the application time (h); D t is the number of days of continuous administration (d); β0 is the intercept; β1, β2, β3, β4 are the linear coefficients; β5, β b ,β7,β8 are quadratic coefficients; β9,β 10 ,β 11 is the interaction term coefficient; ε is the random error term.

[0116] Parameter acquisition method:

[0117] The steps to obtain data through field trials are as follows:

[0118] Step 1: Divide the experimental field into several plots, each with an area of ​​no less than 10m 2 ;

[0119] Step 2: In different cells, follow the preset C, A, T, D t Conduct herbicide applications;

[0120] Step 3: Seven days after the application, randomly select three 1m 2 Sample plot, count the number of weeds in the sample plot;

[0121] Step 4: Calculate weed mortality Where N0 is the number of weeds in the control group, N t is the number of weeds in the treatment group, and the control group was treated with water spraying.

[0122] The weed growth inhibition rate equation is specifically expressed as follows:

[0123]

[0124] In the formula, I g is the weed growth inhibition rate (%); C, A, T, D t The meaning is the same as before; α0 is the intercept; α1, α2, α3, α4 are linear term coefficients; α5, α6, α7, α8 are nonlinear term coefficients; α9, α 10 ,α 11 is the interaction term coefficient; η is the random error term.

[0125] Parameter acquisition method:

[0126] The steps to obtain data through greenhouse pot experiments are as follows:

[0127] Step 1: Prepare soil pots containing target weed seeds, with 3 replicates for each treatment;

[0128] Step 2: When the weeds grow to 3-4 leaves, adjust the temperature according to the preset α, A, T, D t Apply herbicide treatment;

[0129] Step 3: 14 days after treatment, measure the height and fresh weight of weeds;

[0130] Step 4: Calculate weed growth inhibition rate Where W0 is the fresh weight of weeds in the control group, W t is the fresh weight of weeds in the treatment group, and the control group was treated with water spraying.

[0131] The weed regeneration inhibition rate equation is specifically expressed as follows:

[0132]

[0133] Where, R is the weed regeneration inhibition rate (%); C, A, T, D t Same meaning as before; C max is the maximum herbicide concentration (g / L); A max is the maximum application rate (L / ha); γ0 is the intercept; γ1,γ2,γ3,γ4 are linear term coefficients; γ5,γ6,γ7,γ8 are nonlinear term coefficients; γ9,γ 10 ,γ 11 is the interaction term coefficient; ξ is the random error term.

[0134] Parameter acquisition method:

[0135] The steps to obtain data through long-term field observation experiments are as follows:

[0136] Step 1: Divide the experimental field into small plots, with 3 replicates for each treatment and an area of ​​no less than 20m 2 ;

[0137] Step 2: Follow the preset C, A, T, Dt Apply herbicide treatment;

[0138] Step 3: Observe weed regrowth 30, 60, and 90 days after treatment;

[0139] Step 4: Calculate weed regrowth inhibition rate Where N r is the number of regenerated weeds in the control group, N t The number of regenerated weeds in the treatment group and the control group were treated with water spraying.

[0140] The weed height variation equation is specifically expressed as follows:

[0141]

[0142] Where, ΔH is the change rate of weed height (%); C, A, T, D t The meaning is the same as before; δ0 is the intercept; δ1, δ2, δ3, δ4 are linear term coefficients; δ5, δ6, δ7, δ8 are nonlinear term coefficients; δ9, δ 10 ,δ 11 is the interaction term coefficient; ζ is the random error term.

[0143] Parameter acquisition method:

[0144] The data is obtained by regular field measurements. The steps are as follows:

[0145] Step 1: Select representative weeds in the test field, select 10 plants for each treatment, and mark them;

[0146] Step 2: Measure the initial plant height H0 before herbicide treatment;

[0147] Step 3: Follow the preset C, A, T, D t Apply herbicide treatment;

[0148] Step 4: Measure weed height H 7, 14, and 21 days after treatment t ;

[0149] Step 5: Calculate the change rate of weed height

[0150] The weed leaf area index variation equation is specifically expressed as follows:

[0151]

[0152] Where ΔLAI is the change rate of weed leaf area index (%); C, A, T, D t The meaning is the same as before; λ0 is the intercept; λ1,λ2,λ3,λ4 are the linear term coefficients; λ5,λ6,λ7,λ8 are the nonlinear term coefficients; λ9,λ10 ,λ 11 is the interaction term coefficient; ω is the random error term.

[0153] Parameter acquisition method:

[0154] The steps to obtain data through leaf area meter measurement are as follows:

[0155] Step 1: Divide the experimental field into small plots, with 3 replicates for each treatment and an area of ​​1m 2 ;

[0156] Step 2: Before herbicide treatment, measure the initial leaf area index LAI0 using a leaf area meter;

[0157] Step 3: Follow the preset C, A, T, D t Apply herbicide treatment;

[0158] Step 4: Measure the leaf area index (LAI) using a leaf area meter 7, 14, and 21 days after treatment. t ;

[0159] Step 5: Calculate the rate of change of weed leaf area index

[0160] A specific embodiment 5 of the present invention is provided below: This embodiment 5 was conducted in a tobacco field in Shimen Village, Jimo District, Qingdao City, Shandong Province, and was intended to verify the application effect of nicotine aqueous solution as a nicotine herbicide in a tobacco field and determine the optimal herbicide application parameters. The experimental site is in a temperate monsoon climate, and the soil in the test field is sandy loam, with a pH value of 6.8 and an organic matter content of 1.8%.

[0161] Experimental design: This experiment adopted a randomized block design with 16 treatments in total, each treatment was repeated 3 times, and the area of ​​each plot was 20m 2 The experimental factors include the concentration of nicotine aqueous solution (C), application amount (A), application time (T) and continuous application days (Dt). The specific treatments are as follows:

[0162] Nicotine aqueous solution concentration (C): 1.0g / L, 2.0g / L, 3.0g / L, 4.0g / L

[0163] Application rate (A): 150L / ha, 200L / ha, 250L / ha, 300L / ha

[0164] Application time (T): 8:00, 10:00, 14:00, 16:00

[0165] Duration of administration (Dt): 1 day, 2 days, 3 days, 4 days

[0166] Experimental process: 1. Soil preparation: Two weeks before the start of the experiment, the experimental field was deep plowed, leveled and fertilized. 500 kg of compound fertilizer (N:P:K=15:15:15) was applied per hectare.

[0167] Tobacco planting: Select the "Zhongyan 101" variety, use a planting density of 40cm×110cm, plant 5 rows in each plot, and 10 plants in each row.

[0168] Weed survey: Weed survey was conducted 30 days after tobacco transplanting. The main weed species included crabgrass, foxtail grass, amaranth and pigweed.

[0169] Preparation of herbicide: According to the experimental design, nicotine aqueous solutions of different concentrations were prepared. The purity of the nicotine used was 98%, and distilled water was used to prepare the required concentration.

[0170] Herbicide application: Herbicide application began 35 days after tobacco transplanting. Application was carried out according to the different treatment combinations designed in the experiment. A backpack sprayer was used for spraying, with the nozzle height maintained at 50 cm and the spray pressure at 0.3 MPa. The control group was treated with water spraying.

[0171] Data collection:

[0172] Weed mortality: Seven days after the last application, three 1m2 weeds were randomly selected from each plot. 2 Sample plots were taken, the number of weeds in the plots was counted, and the weed mortality rate was calculated.

[0173] Weed growth inhibition rate: 14 days after the last application, three 1m2 weeds were randomly selected from each plot. 2 The height and fresh weight of weeds were measured and the weed growth inhibition rate was calculated.

[0174] Weed regrowth inhibition rate: Observe the weed regrowth 30 days, 60 days and 90 days after the last application of the pesticide, and calculate the weed regrowth inhibition rate.

[0175] Changes in weed height: 10 representative weeds were selected in each plot, and their heights were measured before, 7 days, 14 days, and 21 days after pesticide application after marking, and the change rate of weed height was calculated.

[0176] Changes in weed leaf area index: The leaf area index was measured using the LAI-2200C plant canopy analyzer before, and 7, 14, and 21 days after pesticide application, and the change rate of the weed leaf area index was calculated.

[0177] Data analysis: SPSS26.0 software was used for data processing and analysis, and multiple regression analysis was used to establish the weed control effect equation group.

[0178] Experimental results: 1. Through multiple regression analysis, the weed mortality rate equation was obtained as follows:

[0179]

[0180] Among them, D is the weed mortality rate (%), C is the herbicide concentration (g / L), A is the application amount (L / ha), T is the application time (h), and Dt is the number of days of continuous application (d). The coefficient of determination R2 of this equation is 0.92, indicating that the fitting effect is good.

[0181] Weed growth inhibition rate equation The weed growth inhibition rate equation is as follows:

[0182]

[0183] Wherein, Ig is the weed growth inhibition rate (%), and other variables have the same meanings as above. The coefficient of determination R2 of the equation is 0.89.

[0184] Weed regrowth inhibition rate equation The weed regrowth inhibition rate equation is as follows:

[0185]

[0186] Wherein, R is the weed regeneration inhibition rate (%), and the other variables have the same meanings as above. The coefficient of determination R2 of the equation is 0.87.

[0187] Weed height change equation The weed height change equation is as follows:

[0188]

[0189] Among them, ΔH is the change rate of weed plant height (%), and the other variables have the same meanings as above. The coefficient of determination R2 of this equation is 0.85.

[0190] Weed leaf area index change equation The weed leaf area index change equation is as follows:

[0191]

[0192] Among them, ΔLAI is the change rate of weed leaf area index (%), and the other variables have the same meanings as before. The coefficient of determination R2 of this equation is 0.90.

[0193] According to the above equations, a multi-objective optimization model is constructed, and the objective functions include:

[0194] Maximize: f1(x)=D(C,A,T,D t ) / / Weed mortality rate;

[0195] Maximize: f2(x) = I g (C,A,T,D t) / / Weed growth inhibition rate;

[0196] Minimize: f3(x) = A / / application rate;

[0197] Minimize: f4(x) = D t / / Continued application days;

[0198] Minimize: f5(x)=10C+0.5A+20D t / / Economic cost (assumed units);

[0199] Constraints: 1.0≤C≤4.0; 150≤A≤300; 8≤T≤16; 1≤D t ≤4;

[0200] Where: C is the herbicide concentration (g / L); A is the application amount (L / ha); T is the application time (h); D t is the number of days of continuous administration (d);

[0201] D(C,A,T,D t ), I g (C,A,T,D t ) are the weed mortality rate equation and the weed growth inhibition rate equation, respectively, and their specific expressions are as follows:

[0202]

[0203]

[0204] This multi-objective optimization model aims to simultaneously maximize the weed control effect (f1 and f2), minimize resource input (f3 and f4), and minimize the economic cost (f5) while satisfying the given constraints.

[0205] The multi-objective optimization model was solved using NSGA-II (non-dominated sorting genetic algorithm II), and the optimal herbicide application parameters were obtained as follows: optimal concentration (C): 3.2 g / L, optimal application rate (A): 225 L / ha, optimal application time (T): 10:00, and optimal continuous application days (Dt): 2 days;

[0206] According to the obtained optimal application parameters, the application test of nicotine herbicide was carried out in the actual field. A 1-hectare test field in the tobacco field of Shimen Village, Jimo District, Qingdao City, Shandong Province was selected and divided into a treatment area (0.8 hectares) and a control area (0.2 hectares). Nicotine aqueous solution was sprayed in the treatment area according to the optimal parameters, and no weeding treatment was carried out in the control area.

[0207] The test results are as follows:

[0208] Table 5. Comparison of the application effects of nicotine herbicides

[0209]

[0210]

[0211] As can be seen from Table 5, after applying nicotine herbicide with the optimal parameters, the weed control effect in the treatment area was significantly better than that in the control area. The weed mortality rate in the treatment area reached 89.6%, the weed growth inhibition rate was 85.3%, and the weed regeneration inhibition rate was 78.2%. At the same time, the weed plant height and leaf area index in the treatment area were significantly reduced, by 76.5% and 82.7% respectively. The weeds in the control area continued to grow, and the plant height and leaf area index increased by 15.2% and 10.8% respectively.

[0212] In addition, the application of nicotine herbicides also had a positive effect on tobacco growth. The tobacco yield in the treatment area reached 2850kg / ha, 23.4% higher than that in the control area. The quality of tobacco leaves was also improved, with the tobacco leaves in the treatment area reaching the upper-middle grade, while those in the control area were only the lower-middle grade.

[0213] In order to further verify the application effect of nicotine herbicide, a detailed investigation was conducted on the main weed species in the treatment area and the control area. The results are as follows:

[0214] Table 6. Control effects on major weed species

[0215] Weed Types <![CDATA[Planting density in treatment area (plants / m 2 )]]> <![CDATA[Control area density (plants / m 2 )]]> Control effect (%) Crataegus 3.2 45.6 93.0 Setaria 2.8 38.4 92.7 Amaranth 1.5 22.3 93.3 Quinoa 2.1 29.7 92.9

[0216] Control effect (%) = (density of control area (plants / m 2 )-treatment area density (plants / m 2 )) / density of control area (plants / m 2 )

[0217] As can be seen from Table 6, the nicotine herbicide showed good control effects on the main weed species in the test field. The control effects on crabgrass, foxtail grass, amaranth and quinoa reached 93.0%, 92.7%, 93.3% and 92.9% respectively. This shows that the herbicide has a broad-spectrum herbicidal activity and can effectively control a variety of weeds in the tobacco field.

[0218] In order to evaluate the impact of nicotine herbicides on the environment, residue tests were conducted on the soil and surrounding water bodies after application. The results showed that 30 days after application, no nicotine residues were detected in the soil (detection limit was 0.01 mg / kg). Nicotine was also not detected in the surrounding water bodies (detection limit was 0.005 mg / L). This shows that the nicotine herbicide is easily degraded in the environment and has little impact on the ecological environment.

[0219] In addition, the tobacco leaves in the treatment area and the control area were tested for pesticide residues. The results showed that no nicotine residues were detected in the tobacco leaves in both areas (the detection limit was 0.05 mg / kg), indicating that the herbicide would not have a negative impact on the quality of tobacco leaves.

[0220] In order to evaluate the economic benefits of nicotine herbicide (3.2 g / L nicotine aqueous solution), a cost-effectiveness analysis was conducted on the treatment area and the control area:

[0221] Table 7. Cost-benefit analysis (unit: yuan / hectare)

[0222] project Processing Area Control area Herbicide costs 720 0 Manual weeding costs 0 1800 Tobacco leaf output value 85500 69300 Net income 84780 67500

[0223] As can be seen from Table 7, although the treatment area required additional herbicide costs, the final net income was 17,280 yuan / hectare higher than that of the control area, an increase of 25.6%, due to the elimination of manual weeding costs and the improvement of tobacco leaf yield and quality.

[0224] Several diagrams related to Example 5 are given below:

[0225] Figure 5 This is a contour plot showing how weed mortality changes with changes in herbicide concentration and application rate. Darker colors indicate higher mortality. This plot can help you visually understand the best herbicide concentration and application rate combination.

[0226] Figure 6 This is a bar graph comparing the density of four major weeds (crabgrass, foxtail grass, amaranth, and quinoa) in the treatment area and the control area. The black bar represents the treatment area and the gray bar represents the control area. This figure clearly shows the control effect of nicotine herbicide on various weeds.

[0227] Figure 7 This is a line graph showing the changes in weed growth indicators over time. It shows the changes in weed plant height and leaf area index over time in the treatment area and the control area. The solid line represents the plant height, and the dotted line represents the leaf area index. The black line represents the treatment area, and the gray line represents the control area. This graph intuitively shows the inhibitory effect of herbicides on weed growth.

[0228] Figure 8 This is a comparison chart of tobacco yield and quality. This is a combined chart. The bar chart on the left shows the tobacco yield of the treatment area and the control area, and the line chart on the right shows the tobacco leaf quality grade. This chart also shows the effect of nicotine herbicide on tobacco yield and quality.

[0229] Fig. 9This is a cost-effectiveness analysis chart. This is a grouped bar chart that compares the differences between the treatment area and the control area in terms of herbicide cost, manual weeding cost, tobacco leaf output value and net income. The black column represents the treatment area and the gray column represents the control area. This chart intuitively shows the economic benefits of using nicotine herbicides.

[0230] In summary, this example demonstrates that the application of nicotine aqueous solution as nicotine herbicide in tobacco fields has significant weed control effect and economic benefits. The optimal application parameters (concentration 3.2 g / L, application amount 225 L / ha, application time 10:00, and continuous application for 2 days) determined by multi-objective optimization can effectively control a variety of weeds, improve tobacco yield and quality, and have little impact on the environment and tobacco leaf quality. This method provides a new environmentally friendly and efficient solution for tobacco field weed management.

[0231] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A nicotine herbicide, characterized in that: The active ingredient of the herbicide is nicotine, and the mass concentration of nicotine is 0.30-0.60%.

2. A nicotine herbicide according to claim 1, characterized in that: The nicotine mass concentration of the herbicide is 0.30-0.45%.

3. A nicotine herbicide according to any one of claims 1 to 2, characterized in that: The nicotine in the herbicide is replaced by a dry tobacco leaf extract, and the preparation method of the dry tobacco leaf extract is: grinding the dry tobacco leaves, sieving, adding water to dissolve, and filtering to obtain the dry tobacco leaf extract. Preferably, the filtration is performed using filter paper. More preferably, the dry tobacco leaves are ground and sieved through a 30-60 mesh sieve, 5-20 mL of water is added to each 1 g of powder to dissolve, and the dry tobacco leaf extract is filtered with filter paper to obtain the dry tobacco leaf extract. Most preferably, the dry tobacco leaves are ground and sieved through a 40 mesh sieve, 10 mL of water is added to each 1 g of powder to dissolve, and the dry tobacco leaf extract is filtered with filter paper to obtain the dry tobacco leaf extract.

4. A nicotine herbicide according to claim 3, characterized in that: The herbicide is in the form of a soluble solution or a spray.

5. A method for optimizing the formulation of a nicotine herbicide, characterized in that: The following steps are involved: Step 1, preparing nicotine aqueous solutions of different concentrations, wherein the nicotine mass concentration ranges from 0.15% to 0.60%; Step 2, using the prepared nicotine aqueous solution in a mixed weed control test and a tobacco field weed control test; Step 3: In the mixed weed control test, each concentration of nicotine aqueous solution was sprayed, with a unit spraying amount of 100 mL / m2, and the plant control effect and fresh weight control effect were measured after 10 days; Step 4: In the tobacco field weed control test, 10 days after tobacco transplanting, each concentration of nicotine aqueous solution was sprayed, with a unit spraying amount of 100 mL / m2, and the plant control effect and fresh weight control effect were measured after 10 days; Step 5, comparing the weed control effects of nicotine aqueous solutions of different concentrations in a mixed weed control test and a tobacco field weed control test, and comparing the weed control effects with those of 50% naproxen wettable powder; Step 6: Comprehensively consider the weed control effect and the economic cost of nicotine dosage to determine the optimal concentration range of nicotine herbicide.

6. The method for optimizing the formulation of a nicotine herbicide according to claim 5, characterized in that: The formula for calculating the plant protection effect is: plant protection effect (percentage) = (the number of weeds in the blank control area minus the number of weeds remaining in the treatment area) divided by the number of weeds in the blank control area multiplied by 100; the formula for calculating the fresh weight protection effect is: fresh weight protection effect (percentage) = (the fresh weight of weeds in the blank control area minus the fresh weight of weeds remaining in the treatment area) divided by the fresh weight of weeds in the blank control area multiplied by 100, wherein the blank control area is treated by spraying water.

7. An application of a nicotine herbicide, characterized in that: The active ingredient of the nicotine herbicide is nicotine. The nicotine herbicide is used as a weed killer, preferably as a weed killer in tobacco fields. More preferably, the nicotine herbicide is a nicotine aqueous solution.

8. The use of a nicotine herbicide according to claim 7, characterized in that: When the nicotine herbicide is used as a nicotine aqueous solution as a herbicide for weeds in tobacco fields, the step of determining the optimal herbicide application parameters is further included, specifically including: S10, obtaining multiple groups of historical data, specifically weed control effect data of nicotine herbicides using nicotine aqueous solutions of different concentrations under different application parameters, wherein the application parameters include application amount, application time, and continuous application days; S20, establishing and fitting a weed control effect equation group according to the multiple groups of historical data; S30, using the weed control effect equation group, constructing a multi-objective optimization model to maximize the weed mortality rate and weed growth inhibition rate while minimizing the application amount, continuous application days and economic cost; S40, using a genetic algorithm or a particle swarm optimization algorithm to solve a multi-objective optimization model to obtain optimal herbicide application parameters, including an optimal concentration, an optimal application amount, an optimal application time, and an optimal number of continuous application days; S50. Based on the obtained optimal application parameters, an application test of the nicotine herbicide is conducted in an actual field to verify the weed control effect and make necessary adjustments, and finally determine the optimal application plan of the nicotine herbicide.

9. The use of a nicotine herbicide according to claim 8, characterized in that: The weed control effect equation group includes a weed mortality rate equation, a weed growth inhibition rate equation, a weed regeneration inhibition rate equation, a weed plant height change equation and a weed leaf area index change equation.

10. The use of a nicotine herbicide according to claim 9, characterized in that: The weed control effect data include weed mortality rate, weed growth inhibition rate, weed regeneration inhibition rate, weed plant height change, and weed leaf area index change.

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