Environment-friendly and efficient plant source insecticidal and acaricidal sterilization mixture and preparation method thereof

Abstract

The invention relates to the field of agriculture, and discloses an environment-friendly efficient plant source insecticidal and acaricidal sterilization mixture and a preparation method thereof, and the insecticidal and acaricidal sterilization mixture is composed of the following components in parts by weight: 15-40 parts of tobacco shreds; 10-30 parts of Chinese prickly ash; 10 to 25 parts of pepper; 5 to 20 parts of mint; and 5-15 parts of lemon. The tobacco shreds are dry leaves of Virginia type flue-cured tobacco, the tobacco shreds are subjected to primary baking and re-baking process treatment, the leaves are complete, the color is golden yellow to orange yellow, and the nicotine reference content of the tobacco shreds is 3.0%; the Chinese prickly ash is dry peel of Dahongpao Chinese prickly ash, the Chinese prickly ash is dark red, the peel is open, Chinese prickly ash seeds and branches are removed, and the volatile oil content of the Chinese prickly ash is 6.0%. By combining various plant source components, an efficient and environment-friendly pest control scheme is provided, the pest killing effect and the control durability are remarkably improved, and meanwhile the environmental pollution risk is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of agriculture, in particular to an environmentally friendly and efficient plant source insecticide and miticide sterilization mixture and a preparation method thereof. BACKGROUND

[0002] In modern agricultural production, pest control has always been a key factor for high yield of crops. With global climate change and diversification of crop planting, the number of pests is increasing, posing a serious challenge to agriculture. Therefore, it is particularly important to develop efficient and safe pesticides.

[0003] The existing technology mainly relies on synthetic chemical pesticides, which can reduce the number of pests to some extent and maintain the yield of crops. Some chemical pesticides can produce rapid effects and significantly improve the growth conditions of crops in the short term, reducing economic losses. However, these traditional pesticides often have strong specificity and cannot cover a variety of pests, and show great limitations in integrated control. This makes farmers need to frequently change or combine the use of multiple chemicals in the control process, which not only increases the cost but also affects the convenience of use.

[0004] However, there are still some deficiencies in the existing technology. Long-term use of chemical pesticides leads to the development of pesticide resistance, which gradually weakens the control effect and even causes pollution to farmland and the environment. Relying solely on toxicity to control pests cannot fundamentally curb the reproduction and spread of pests. In addition, the research on plant extract components in the existing technology is relatively superficial, which leads to the potential effectiveness of many natural ingredients not being fully developed and utilized. SUMMARY

[0005] In view of the deficiencies of the prior art, the present application provides an environmentally friendly and efficient plant source insecticide and miticide sterilization mixture and a preparation method thereof, which solves the problems of increased pesticide resistance, environmental pollution and ineffective response to multiple pests caused by chemical pesticides in the prior art.

[0006] To achieve the above purpose, the present application realizes the following technical scheme: an environmentally friendly and efficient plant source insecticide and miticide sterilization mixture, which is composed of the following components by weight: Tobacco shred: 15-40 parts, the tobacco shred is a dry leaf of Virginia type flue-cured tobacco, which is treated by primary curing and re-curing process, the leaf is complete, the color is golden yellow to orange yellow, and the nicotine base content of the tobacco shred is 3.0%; the core active substance in the tobacco shred is nicotine, which is a classic acetylcholine competitive agonist; nicotine can act irreversibly on the nicotinic acetylcholine receptor of the postsynaptic membrane; this combination will cause persistent depolarization of neurons, leading to disorder of nerve signal transmission; finally, the pests will appear spasm, paralysis and even death due to overexcitation of the nervous system; Zanthoxylum bungeanum: 10-30 parts, the Zanthoxylum bungeanum is dried pericarp of Zanthoxylum bungeanum, the Zanthoxylum bungeanum is dark red, pericarp is open, Zanthoxylum bungeanum seed and branch are removed, and the volatile oil content of the Zanthoxylum bungeanum is 6.0 %; the key active ingredient of Zanthoxylum bungeanum is Zanthoxylum mace, mainly acting on voltage-gated sodium ion channels and potassium ion channels on nerve cell membranes; Zanthoxylum mace can interact with these ion channels, interfere with the normal opening and closing, and thus block or disturb the normal conduction of nerve impulses; the effect is manifested on pests as rapid muscle paralysis and movement disorder, that is, "knockdown" effect; Capsicum annuum: 10-25 parts, the Capsicum annuum is dried fruit of Capsicum annuum var. baccatum, the dried fruit is complete in shape, has wrinkle specific to the variety on the surface, and is red in color, and the total content of capsaicin in the Capsicum annuum is 2.0 %; the core active ingredient of Capsicum annuum is capsaicin; it can specifically activate the nociceptors on the body surface of pests, especially transient receptor potential vanilloid subtype 1 channels; the activation can bring pests strong burning and stimulating sensation, thereby generating strong repellent effect, and pests actively avoid the application area; meanwhile, high-concentration capsaicin can also destroy the membrane structure of the body wall cells of pests when directly contacted, and has a certain contact-killing effect; Mentha haplocalyx: 5-20 parts, the raw material of the Mentha haplocalyx is stem and leaf part of Mentha haplocalyx harvested before the flowering stage, the Mentha haplocalyx is subjected to shade drying treatment under ventilation conditions, and the final water content is less than 12.0 %; the main active ingredient of the Mentha haplocalyx is menthol; menthol itself has significant olfactory repellent effect, and its strong smell can interfere with the identification of pests to the smell of host plants, and is complementary to the gustatory repellent effect of Capsicum annuum; in addition, menthol also has a certain paralyzing effect on the nervous system of insects; the volatile component of Mentha haplocalyx can act as a synergist, and by affecting the permeability of the body wall of pests, it creates more favorable conditions for the penetration and action of other active ingredients; Citrus limon: 5-15 parts, the key active substance rich in the Citrus limon is D-limonene; the effect of the Citrus limon is not direct killing, but as a high-efficiency natural penetrating agent; D-limonene is a nonpolar terpene compound, has strong affinity and dissolving capacity for the waxy layer of the body wall of insects; it can effectively dissolve the protective waxy layer, thereby opening a "channel", so that the active molecules in the formula, which are originally difficult to penetrate the body wall due to strong polarity, can penetrate into the pests more quickly and in a larger amount, and directly reach the target.

[0007] The application also provides a preparation method of the environment-friendly and high-efficiency plant source insecticide, acaricide and sterilization mixture, comprising the following steps: S1, the dried raw materials of the tobacco, Zanthoxylum bungeanum, Capsicum annuum, Mentha haplocalyx and Citrus limon are respectively taken, a universal pulverizer is used for pulverizing treatment, all the dried raw materials pass through a standard sieve of 80-120 meshes, the plant fine powder of the tobacco, Zanthoxylum bungeanum, Capsicum annuum, Mentha haplocalyx and Citrus limon is obtained, and is packed and sealed for use. S2, after the tobacco shred fine powder is screened, 8-10 times deionized water of tobacco shred fine powder is added, the pH value of the material liquid is adjusted to 9.0-10.0, constant temperature stirring extraction is carried out at 55-65 DEG C for 1.5-2.0 hours, filtration is carried out, and the filtrate is collected to obtain a nicotine extract; S3, the pepper fine powder, chili fine powder, mint fine powder and lemon fine powder prepared in step S1 are mixed and loaded into an extraction kettle, and are extracted by using a subcritical fluid extraction method under the conditions of a temperature of 35-45 DEG C and a pressure of 2.0-3.0 MPa to obtain a composite plant essential oil extract; S4, the nicotine extract is reduced pressure concentrated under the conditions of a vacuum degree of-0.08 to-0.09 MPa and a temperature of 60-70 DEG C until a thick leaching paste is formed to obtain a nicotine concentrate; S5, the nicotine concentrate and the composite plant essential oil extract are mixed according to the weight ratio of the feeding proportion, high shear pre-emulsification is carried out at a rotating speed of 6000-8000 rpm for 15-20 minutes to form a primary emulsion, the primary emulsion is pumped into a high pressure homogenizer, and cycle homogenization treatment is carried out under a pressure of 110-140 MPa to obtain a final mixture.

[0008] Preferably, in step S1, the pulverization treatment by using the universal pulverizer comprises the following steps: The dry raw materials of the tobacco shred, pepper, chili, mint and lemon are respectively subjected to coarse pulverization treatment so that the particle size is less than 10 mm, and the dry raw materials subjected to the coarse pulverization treatment are fed into a micro-pulverizer with a grading device to be finely pulverized until the materials all pass through the standard sieve with a mesh size of 80-120; By pulverizing the raw materials into fine powder with a mesh size of 80-120, the specific surface area of the materials is greatly increased; this enables the subsequent extraction solvent to be in maximum contact with the plant cells, thereby significantly shortening the mass transfer distance and enabling the active ingredients in the cells to be quickly and fully dissolved out; the design of the two-step pulverization method takes into account the efficiency and equipment protection, and the micro-pulverizer with a grading device ensures the uniformity of the particle size of the final powder.

[0009] Preferably, in step S2, the adjustment of the pH value of the material liquid to 9.0-10.0 comprises the following steps: Sodium hydroxide or sodium carbonate is dissolved in deionized water to prepare an alkaline standard solution with a concentration of 1.0-2.0 mol / L; Under the condition of continuous stirring, the alkaline standard solution is slowly added to the material liquid by using a peristaltic pump, and the pH value of the material liquid is monitored in real time by using an online pH meter; when the pH value reaches and stabilizes in the range of 9.0-10.0, the addition of the alkaline standard solution is stopped; In the plant body, nicotine is mostly in the form of protonated hydrochloride, citrate and other forms, which has good water solubility but is tightly combined with plant tissues; by accurately controlling the pH value to 9.0-10.0 alkaline environment, the deprotonation reaction of nicotine salt is promoted, and the free base form is converted; the free base form of nicotine is more easily separated from the plant tissue matrix and dissolved in water; this accurate control ensures that the pH value of the extraction system can be stably maintained in the optimal interval, which not only guarantees the highest dissolution rate of nicotine, but also avoids the degradation of nicotine structure caused by local over-alkaline, thereby realizing the efficient and non-destructive extraction of the core active ingredient.

[0010] Preferably, in step S3, the extraction by subcritical fluid extraction method comprises the following steps: The pepper powder, chili powder, mint powder and lemon powder are mixed and loaded into an extraction kettle and sealed, and after sealing, liquefied n-butane is pumped into the extraction kettle as an extractant until the preset solvent to raw material mass ratio is reached; Under the temperature and pressure conditions, the extractant is circulated and fully contacted with the material in the extraction kettle for 1.0-1.5 hours, and after the extraction is completed, the extractant containing the extract is pumped into a separation kettle, and the extractant is gasified and separated from the extract by reducing the pressure; the composite plant essential oil extract is collected at the bottom of the separation kettle, and the gasified extractant is recovered; n-butane is in a liquid state at a temperature close to room temperature of 35-45℃ and a moderate pressure of 2.0-3.0 MPa, and as a non-polar solvent, it has strong solubility for the fat-soluble components of essential oils and alkaloids in plants; after extraction is completed, only the system pressure needs to be reduced, and n-butane will rapidly gasify due to its extremely low boiling point, perfectly separating from the extracted material, and almost no residue.

[0011] Preferably, in step S4, the reduced pressure concentration comprises the following steps: The nicotine extract is transferred to a rotating flask of a rotary evaporator, the rotating flask is placed in a water bath and heated to the temperature, and the rotary evaporator is started to rotate the rotating flask at a speed of 40-60 rpm; Using the physical principle that the boiling point of a liquid decreases as its surface pressure decreases; under vacuum conditions of-0.08 to-0.09 MPa, the boiling point of water can be significantly reduced from 100℃ to 60-70℃; the rotary evaporator continuously rotates the flask, forming a large and constantly updated film on the inner wall, greatly increasing the evaporation area; through this low-temperature and high-efficiency evaporation method, a large amount of water can be quickly removed under mild conditions to obtain a paste-like nicotine concentrate, effectively avoiding the oxidation or degradation of nicotine that may be caused by long-time high-temperature in traditional atmospheric heating concentration.

[0012] The application provides an environmentally friendly and efficient plant source insecticide and acaricide and sterilization mixture and a preparation method thereof. 1、The application adopts a composite plant extraction technology, and by combining components such as lemons and peppers, the lethal effect on pests is significantly improved. Compared with the single-component insecticide in the prior art, the problem of insufficient insecticidal efficiency is solved.

[0013] 2、The composition of the application successfully improves the repellent effect by enhancing permeability and nerve stimulation. Compared with the traditional insect repellent which only relies on the smell of repellent, the problem of unsatisfactory pest repellent effect is solved, so that houseflies and other pests are more easily driven away.

[0014] 3、The application adopts a multi-target mechanism, which can effectively inhibit the reproductive capacity of pests. Compared with the products in the prior art which lack overall control strategies, the product of the application has more advantages in inhibiting the growth of pests, and reduces the successful reproduction rate of pests.

[0015] 4、The step-by-step targeted extraction method of the application improves the activity of the extracted components. Compared with the conventional extraction method, this technical solution solves the problems of low extraction efficiency and insufficient component activity, so that each component can play a better insecticidal effect, thereby improving the effectiveness and safety of the overall product. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 The application provides an environmentally friendly and efficient plant source insecticide and acaricide and sterilization mixture and a preparation method thereof. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the application will be described in detail below with reference to the drawings of the application specification. Obviously, the described embodiments are only a part of the embodiments of the application, not all embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the application.

[0018] Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available or can be prepared by known methods.

[0019] Please refer to the attached Figure 1 : Example 1 Component ratio (ratio by weight): tobacco: 30 parts, pepper: 20 parts, chili pepper: 15 parts, mint: 10 parts, lemon: 10 parts.

[0020] Preparation steps Raw material pretreatment 30 parts of dried tobacco, 20 parts of dried Sichuan pepper, 15 parts of dried chili, 10 parts of dried mint and 10 parts of dried lemon were respectively crushed by a universal crusher. The crushing process was performed in a way of coarse crushing followed by fine crushing. Finally, all the dried raw materials passed through a standard sieve of 100 mesh to obtain five independent plant powders which were sealed and stored.

[0021] Nicotine extraction: After the screening, 30 parts of tobacco powder were added with 270 parts (9 times by weight) of deionized water. Under continuous stirring, 1.5 mol / L sodium hydroxide solution was slowly added by using a peristaltic pump, and the pH value of the solution was monitored in real time by using an online pH meter. The pH value of the solution was accurately adjusted and stabilized at 9.5. Then, the solution was stirred at 60°C for 1.8 hours. After the extraction was completed, the solution was filtered to obtain a nicotine extract.

[0022] Composite plant essential oil extraction: The 20 parts of Sichuan pepper powder, 15 parts of chili powder, 10 parts of mint powder and 10 parts of lemon powder were uniformly mixed, and the mixed powder was loaded into an extraction kettle. The composite plant essential oil extract was obtained by using a subcritical fluid extraction method under the conditions of a temperature of 40°C and a pressure of 2.5 MPa for 1.2 hours.

[0023] Nicotine extract concentration: The nicotine extract was transferred to a rotary evaporator and concentrated under reduced pressure at a vacuum degree of -0.085 MPa and a water bath temperature of 65°C until a thick extract was formed to obtain a nicotine concentrate.

[0024] Compound and homogenization: The nicotine concentrate obtained in step S4 and the composite plant essential oil extract obtained in step S3 were mixed according to the weight ratio of the original feed. The mixture was subjected to high shear pre-emulsification at a speed of 7000 rpm for 18 minutes to form a primary emulsion. Then, the primary emulsion was pumped into a high-pressure homogenizer and subjected to cycle homogenization treatment twice at a pressure of 120 MPa to obtain the final mixture.

[0025] Example 2: Component ratio (by weight ratio): tobacco 15 parts, Sichuan pepper 10 parts, chili 10 parts, mint 5 parts, lemon 5 parts.

[0026] Preparation steps: Raw material pretreatment: The dried raw materials were crushed to pass through a standard sieve of 80 mesh to obtain five independent plant powders which were sealed and stored.

[0027] Nicotine extraction: Take the 15 parts of tobacco powder after screening, add 120 parts (8 times weight) of deionized water, adjust the pH value of the material liquid to 9.0, constant temperature stirring extraction at 55℃ for 1.5 hours, filter, collect the filtrate, get the nicotine extract.

[0028] Composite plant essential oil extraction: Mix the fine powder of Zanthoxylum bungeanum, Capsicum annuum, Mentha haplocalyx and lemon, extract for 1.0 hour at a temperature of 35℃ and a pressure of 2.0 MPa by using subcritical fluid extraction method, get the composite plant essential oil extract.

[0029] Nicotine extract concentration: The nicotine extract obtained in step S2 is reduced pressure concentrated under the condition of vacuum degree-0.08 MPa and temperature 60℃, until the thick extract is formed, get the nicotine concentrate.

[0030] Compound and homogeneous agent: Mix the nicotine concentrate and the composite plant essential oil extract, high shear pre-emulsification at a speed of 6000 rpm for 15 minutes, form the primary emulsion. Immediately pump the primary emulsion into the high pressure homogenizer, cycle homogenization treatment at a pressure of 110 MPa, get the final mixture.

[0031] Example 3: Component ratio (proportioned by weight): tobacco 40 parts, Zanthoxylum bungeanum 30 parts, Capsicum annuum 25 parts, Mentha haplocalyx 20 parts, lemon 15 parts.

[0032] Preparation steps: Raw material pretreatment: Pulverize the dry raw materials respectively, make all the dry raw materials pass through the standard sieve of 120 mesh, get five kinds of independent plant fine powder, seal and store separately.

[0033] Nicotine extraction: Take 40 parts of tobacco powder after screening, add 400 parts (10 times weight) of deionized water, adjust the pH value of the material liquid to 10.0, constant temperature stirring extraction at 65℃ for 2.0 hours, filter, collect the filtrate, get the nicotine extract.

[0034] Composite plant essential oil extraction: Mix the fine powder of Zanthoxylum bungeanum, Capsicum annuum, Mentha haplocalyx and lemon, extract for 1.5 hours at a temperature of 45℃ and a pressure of 3.0 MPa by using subcritical fluid extraction method, get the composite plant essential oil extract.

[0035] Nicotine extract concentration: The nicotine extract solution is concentrated under reduced pressure at a vacuum degree of -0.09 MPa and a temperature of 70°C until a thick extract paste is formed, thereby obtaining a nicotine concentrate.

[0036] Compound and homogeneous preparation: The nicotine concentrate and the compound plant essential oil extract are mixed, and then pre-emulsified at a high shear speed of 8000 rpm for 20 minutes to form a primary emulsion. The primary emulsion is then pumped into a high-pressure homogenizer and subjected to cyclic homogenization at a pressure of 140 MPa for 3 times to obtain a final mixture.

[0037] Comparative Example 1: Compared with Example 1, the difference is that no lemon component is added as a key physical penetration agent, and the rest is the same.

[0038] Comparative Example 2: Compared with Example 1, the difference is that no Sichuan pepper component is added as a component responsible for rapid knockdown, and the rest is the same.

[0039] Comparative Example 3: Compared with Example 1, the difference is that no Sichuan pepper component is added, and the addition of Sichuan pepper powder is omitted, and the rest is the same.

[0040] Experiment 1: Purpose of the experiment: Test the lethal effect of each sample on a specific pest (such as green bean beetle), and evaluate the influence of different components and preparation methods on its toxicity.

[0041] Experimental steps: Pre-treatment of pests: Select green bean beetles of the same age and weight, about 100, and place them in a constant temperature and humidity laboratory environment for 24 hours of adaptation.

[0042] Prepare samples: Dilute each sample according to the ratio of each sample to ensure consistent liquid concentration (e.g., 1:10 dilution).

[0043] Spray treatment: Each sample (Example 1, Comparative Example 1, Comparative Example 2, Comparative Example 3, control group) is sprayed into the corresponding container to ensure uniform coverage of the bottom of each container, and the spraying is repeated 3 times to ensure the treatment effect of each sample.

[0044] Place the pests: Place the same number (20) of green bean beetles into each container to ensure uniform distribution in each group.

[0045] Observation and recording: Record the number of live and dead pests in each container at 0.5 hours, 1 hour, 6 hours, 24 hours, and 48 hours after treatment.

[0046] Set a fixed observation time, such as every hour, and record the activity of the insects and whether there is a death phenomenon.

[0047] Data analysis: Calculate the mortality rate at each time point and calculate the LC50 value.

[0048] Organize the observation results into a table for subsequent analysis and comparison (see Table 1 for experimental results).

[0049] Table 1: Test results of insecticidal effect From Table 1: The results of this experiment show the insecticidal effect of each sample on green bean insects, suggesting the key role of each component in the composition in synergistic action. The lemon component contained in Example 1 serves as an important physical penetration agent, significantly improving the penetration performance of the core active ingredients, enabling water-soluble toxicants such as nicotine to enter the pest body more effectively, causing paralysis of the nervous system. This feature is directly reflected in the experimental data, with Example 1 having significantly lower survival rates at 24 hours and 48 hours than other comparative groups, indicating its rapid and efficient lethal effect, which is closely related to the good combination of water-soluble and fat-soluble components.

[0050] In addition, the presence of pepper in Example 1 provides additional rapid knockdown effect. The cannabinoids in pepper cause instantaneous numbness to the pest's nervous system, making it unable to avoid further attacks by toxins. The experimental data shows that Example 1 has significantly lower survival rates in the early time period than Comparative Example 2, indicating that the formulation without the pepper component fails to achieve the same degree of rapid knockdown effect. Therefore, the effective action of pepper in the composition is synergistically enhanced by the physical and biochemical mechanisms, enhancing the overall insecticidal effect.

[0051] In contrast, the removal of core components such as lemon and pepper in Comparative Examples 1 and 2 significantly reduces the insecticidal efficiency, demonstrating the scientificity and rigor of the composition design of the present invention. This multi-target attack strategy not only improves the insecticidal efficiency, but also effectively suppresses the development of pest resistance, enhancing the long-term use effect of pesticides. The results of this experiment further confirm the synergistic action of each component in the composition and the necessity of step-by-step targeted extraction process to maintain the activity of the components, fully demonstrating the innovation and application potential of the present invention in the field of plant-derived pesticides.

[0052] Experiment 2: Purpose of the experiment: Test the repellent effect of each sample on a specific pest (such as houseflies), and evaluate the influence of different components and preparation methods on the repellent performance.

[0053] Experimental steps: Setting up the experimental site: Prepare a transparent plastic box in the laboratory, dividing it into left and right areas, ensuring that each area is of equal size.

[0054] Spray the sample to be tested in the left area, and leave the right area empty as a control, ensuring no external interference.

[0055] Preparing the sample: According to the proportions of each sample, fill the spreader with Example 1, Comparative Example 1, Comparative Example 2, Comparative Example 3, and deionized water respectively.

[0056] Placing pests: First, place 100 houseflies evenly in the center area of the transparent plastic box, allowing them to adapt to the environment for 15 minutes, ensuring no external interference affects the initial activity.

[0057] Spraying treatment: Use the spreader to spray each sample in the left area, ensuring uniform spraying and equal spray volume for each sample.

[0058] The control group (deionized water) does not undergo spraying.

[0059] Observation and recording: At 0.5 hours, 1 hour, 3 hours, 6 hours, and 12 hours after spraying, record the number of houseflies entering the left treatment area and calculate the repellency rate.

[0060] Observe and record the distribution of houseflies in both areas at each time point, focusing on their dynamic entry into the treatment area (see Table 2 for experimental results).

[0061] Table 2: Repellent effect test results data From Table 2, we can see: The experimental results show that the composition used in Example 1 has a significant advantage in repelling houseflies, with a repellency rate higher than other comparative samples at each time point. The key to this effect lies in the limonene component in the lemon, which acts as an effective physical penetration agent, not only enhancing the penetration ability of other active ingredients, but also inhibiting the behavior of pests. Limonene itself stimulates the sensory organs of pests, changing their behavior and feeding patterns, thereby achieving repellency. In the experiment, Example 1 showed a high repellency rate in a short time, which exactly reflects the effectiveness of this mechanism.

[0062] In addition, the mace in the composition also plays an important role. It has a stimulating effect on the nervous system of the housefly, making the pest feel strong discomfort, thus more inclined to avoid the treated area. The experimental data show that the repellency rate of Example 1 is much higher than that of Comparative Examples 2 and 3 at each time period, indicating that the formula without the component of pepper fails to form the same effective repellent effect. The synergistic effect of pepper and lemon enables the composition to trigger multiple biological responses in the process of insect repellence, thereby achieving a fast and effective repellent effect.

[0063] The experimental results also emphasize the advantages of the composition of the present application compared with the control group, especially in terms of the durability of the repellent effect. Over time, the repellent effect of Example 1 is still significant, while the repellency of Comparative Example 1 is greatly reduced, showing the limitations of single-component combinations in repellence. This further confirms the effectiveness of the comprehensive composition in the repellent strategy, which is implemented through multiple targets and mechanisms, and the overall phenomenon fully demonstrates the innovation and practical application potential of the present application in the field of plant source pesticides.

[0064] Experiment 3: Purpose of the experiment: Test the effect of different samples on the resistance of pests (such as green bean worms), and evaluate the effect of each component on the survival and reproductive characteristics of pests.

[0065] Experimental steps: Pre-treatment of pests: Select green bean worms of the same age and weight, about 100, and place them in a constant temperature and humidity laboratory environment for 24 hours of adaptation.

[0066] Prepare samples: Prepare Example 1, Comparative Example 2, Comparative Example 3, and deionized water according to the proportions of each sample.

[0067] Drug application: Spray the above samples to the bottom of each group of containers respectively, ensuring uniform spraying of each sample with the same amount. For example, apply the same dose of product to the bottom of each group of containers.

[0068] Place the pests: Gently place the same number (20) of green bean worms into each container, ensuring uniform distribution in each group. Then observe and record for 20 minutes to allow the pests to adapt.

[0069] Observation and recording: Record the survival of pests in each group 24 hours and 48 hours after drug application, and count the number of live and dead cases in each group. Record the number of eggs, hatching, and number of surviving newly hatched larvae in each group, and observe the development of the eggs under a microscope.

[0070] Any abnormal behavior, such as reduced feeding and decreased activity, was also monitored (see Table 3 for experimental results).

[0071] Table 3: Resistance test results data From Table 3, it can be seen that: The experimental results show that Example 1 is significantly better than Comparative Examples 2 and 3 in controlling green bean worms, highlighting the synergistic effect of the key ingredients in the composition. The lemon component in Example 1 not only helps to enhance the penetration of other effective ingredients, but also affects the sensitivity of pests to toxic agents by changing their physiological state. Studies have shown that the active ingredients in lemon can increase the permeability of the insect body, thereby accelerating the absorption of toxins such as nicotine, causing a violent reaction in the nervous system in a short period of time, and ultimately leading to death. Therefore, Example 1 shows satisfactory results in terms of survival rate and reproductive success rate.

[0072] On the other hand, as an important component of Example 1, Sichuan pepper gives pests a quick knockdown effect through its unique pungent component. As can be seen from the experimental data, the survival rate of Example 1 at 48 hours is significantly lower than that of Comparative Examples 2 and 3, indicating that the presence of Sichuan pepper effectively inhibits the survival and reproduction of pests. This mechanism is attributed to the rapid activation of the nervous system by Sichuan pepper, affecting the normal activity and physiological processes of pests, reducing their survival and reproductive ability. Compared with other comparative groups, its reproductive success rate and survival rate are significantly lower, further verifying the importance of Sichuan pepper in the composition.

[0073] The experimental results demonstrate the superiority of the composition of the present application in controlling pests, especially through the combined action of multiple targets and biological mechanisms to reduce the survival rate of pests and inhibit reproduction. This not only indicates the synergistic effect between ingredients, but also emphasizes the importance of step-by-step targeted extraction process in maintaining biological activity.

[0074] Although embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and alterations can be made thereto without departing from the principles and spirit of the present application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An environmentally friendly and highly effective botanical insecticide and acaricide sterilization mixture, characterized in that: The insecticide, acaricide and sterilization mixture is composed of the following components in parts by weight: Tobacco: 15-40 servings; Sichuan peppercorns: 10-30 portions; Chili pepper: 10-25 servings; Mint: 5-20 servings; Lemon: 5-15 servings.

2. The environmentally friendly and highly effective botanical insecticide and acaricide sterilization mixture according to claim 1, characterized in that: The shredded tobacco is dried leaves of Virginia-type flue-cured tobacco, which has been processed through primary and secondary curing processes. The leaves are complete and have a golden to orange color. The nicotine baseline content of the shredded tobacco is 3.0%.

3. The environmentally friendly and highly effective botanical insecticide and acaricide sterilization mixture according to claim 1, characterized in that: The Sichuan pepper is the dried peel of Dahongpao Sichuan pepper, the Sichuan pepper is dark red, the peel is open, the Sichuan pepper seeds and stalks have been removed, and the volatile oil content of the Sichuan pepper is 6.0%.

4. The environmentally friendly and highly effective botanical insecticide and acaricide sterilization mixture according to claim 1, characterized in that: The pepper is the dried fruit of the Indian ghost pepper variety. The dried fruit has a complete shape, has variety-specific wrinkles on the surface, and is red in color. The total capsaicin content in the pepper is 2.0%.

5. The environmentally friendly and highly effective botanical insecticide and acaricide sterilization mixture according to claim 1, characterized in that: The raw materials of the mint are the stems and leaves of Asian mint harvested before the full flowering period. The mint is shade-dried under light-proof and ventilated conditions until the final moisture content is less than 12.0%.

6. A method for preparing an environmentally friendly and efficient botanical insecticide and acaricide sterilization mixture, for preparing an environmentally friendly and efficient botanical insecticide and acaricide sterilization mixture according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1, respectively weigh the dry raw materials of the tobacco, pepper, pepper, mint and lemon, use a universal grinder to grind them, make all the dry raw materials pass through an 80-120 mesh standard sieve, obtain the plant fine powder of the tobacco, pepper, pepper, mint and lemon, and pack and seal them for standby use; S2. Take the sieved tobacco powder, add deionized water 8-10 times heavier than the tobacco powder, adjust the pH value of the liquid to 9.0-10.0, and extract at a constant temperature of 55°C-65°C with stirring for 1.5-2.0 hours. Filter and collect the filtrate to obtain a nicotine extract; S3, mixing the fine Zanthoxylum bungeanum powder, the fine chili powder, the fine mint powder and the fine lemon powder obtained in step S1 and charging them into an extraction kettle, extracting them by subcritical fluid extraction at a temperature of 35° C. to 45° C. and a pressure of 2.0 MPa to 3.0 MPa to obtain a composite plant essential oil extract; S4, concentrating the nicotine extract under reduced pressure at a vacuum degree of -0.08 to -0.09 MPa and a temperature of 60° C. to 70° C. until a thick extract is formed to obtain a nicotine concentrate; S5. The nicotine concentrate and the composite plant essential oil extract are mixed in a weight ratio, and high-shear pre-emulsification is performed at a speed of 6000 rpm to 8000 rpm for 15-20 minutes to form a primary emulsion. The primary emulsion is pumped into a high-pressure homogenizer and circulated homogenized at a pressure of 110 MPa to 140 MPa to obtain a final mixture.

7. The method for preparing an environmentally friendly and highly effective botanical insecticide and acaricide sterilization mixture according to claim 6, characterized in that: In step S1, the pulverizing process using a universal pulverizer includes the following steps: The dried raw materials of tobacco, pepper, chili, mint and lemon are coarsely crushed to make the particle size less than 10 mm, and the coarsely crushed dried raw materials are sent to a micro-pulverizer with a grading device for fine grinding until all the materials pass through the 80-120 mesh standard sieve.

8. The method for preparing an environmentally friendly and highly effective botanical insecticide and acaricide sterilization mixture according to claim 6, characterized in that: In step S2, adjusting the pH value of the feed solution to 9.0-10.0 comprises the following steps: Dissolve sodium hydroxide or sodium carbonate in deionized water to prepare an alkaline standard solution with a concentration of 1.0-2.0 mol / L; Under continuous stirring, the alkaline standard solution is slowly added to the adjusted feed solution using a peristaltic pump, and the pH value of the feed solution is monitored in real time using an online pH meter. When the pH value reaches and stabilizes in the range of 9.0-10.0, the addition of the alkaline standard solution is stopped.

9. The method for preparing an environmentally friendly and highly effective botanical insecticide and acaricide sterilization mixture according to claim 6, characterized in that: In step S3, the extraction using subcritical fluid extraction includes the following steps: The fine powder of Sichuan pepper, the fine powder of chili pepper, the fine powder of mint and the fine powder of lemon are mixed and placed into an extraction kettle and sealed. After sealing, liquefied n-butane is pumped into the extraction kettle as an extractant until a preset mass ratio of solvent to raw materials is reached; Under the temperature and pressure conditions, the extractant is allowed to circulate in the extraction kettle and fully contact the material for 1.0-1.5 hours. After the extraction is completed, the extractant containing the extract is pumped into a separation kettle, and the extractant is vaporized and separated from the extract by reducing the pressure; the composite plant essential oil extract at the bottom of the separation kettle is collected, and the vaporized extractant is recovered at the same time.

10. The method for preparing an environmentally friendly and highly effective botanical insecticide and acaricide sterilization mixture according to claim 6, characterized in that: In step S4, the reduced pressure concentration comprises the following steps: The nicotine extract was transferred to a rotary bottle of a rotary evaporator, and the rotary bottle was placed in a water bath and heated to the temperature. At the same time, the rotary evaporator was turned on to rotate the rotary bottle at a speed of 40-60 rpm.

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