Botanical pesticide microcapsule capable of effectively preventing and treating fall webworm and preparation method of botanical pesticide microcapsule

Abstract

The invention relates to the technical field of novel botanical pesticide preparations, and particularly discloses a botanical pesticide microcapsule capable of effectively preventing and treating fall webworms and a preparation method thereof.According to the microcapsule, aesculetin serves as an original medicine, gelatin serves as a wall material, the concentration of the wall material is 3%, the core-wall ratio (W / W) is 1: 5, the concentration of sodium sulfate is 20%, the reaction temperature is 50 DEG C, the stirring speed is 500 r / min, and the stirring time is 30 min; the aesculetin microcapsule with the pH value of 4 has good performance characterization. According to the invention, the wall material gelatin of the microcapsule is a natural polymer material, and is low in price and harmless to the environment. According to the aesculetin microcapsule, the surface is smooth, the particle size distribution of the microcapsule is uniform, the toxicity of the aesculetin microcapsule to non-target organisms is remarkably reduced, the original drug effect and activity can be kept and the slow release capacity of the aesculetin can be enhanced after the aesculetin is microencapsulated, and the aesculetin microcapsule is simple in process, easy to operate and mild in reaction condition and has a good application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of novel botanical pesticide preparations, and in particular relates to a botanical pesticide microcapsule capable of effectively preventing and controlling the gypsy moth and a preparation method thereof. Background Art

[0002] The gypsy moth (Hyphantria cunea), also known as the "fall moth", belongs to the Erebidae family of the Lepidoptera order and is white in overall appearance. The gypsy moth mainly feeds on plant leaves as larvae. It harms a wide range of trees and eats a large amount of food. When the damage is serious, it can eat all the leaves of the host plant and gnaw on the bark, thereby weakening the tree's resistance to damage and stress, and seriously affecting the growth of forests. At present, chemical pesticides are still the first choice for the prevention and control of the gypsy moth. However, the long-term use of chemical pesticides will enhance the resistance of herbivorous insects and reduce the control effect. In addition, what is more serious is that traditional chemical pesticides are extremely difficult to degrade and remain in the food chain of the ecosystem, threatening the ecological environment and even human health. Some plant-derived substances have been proven to have biological activities such as repelling feeding, contact killing, and inhibiting growth and development of herbivorous insects, which can achieve or even exceed the control effect of chemical pesticides. In addition, plant-derived pesticides have advantages that chemical pesticides do not have, including not easy to produce resistance, low toxicity or non-toxicity, and natural environmental protection. Therefore, there is an urgent need to develop safe, effective, and environmentally friendly botanical pesticides to replace traditional chemical pesticides.

[0003] Microencapsulation is a technology that uses physical, chemical or physicochemical methods to encapsulate the core material in the wall material, so that the core material is slowly released through the capsule wall and its efficacy is prolonged without destroying itself. This technology has been widely used in the fields of pesticides, pharmaceuticals, biotechnology, cosmetics and food. Compared with raw materials, controlled-release microcapsule preparations have many advantages, such as effectively reducing the impact of external environmental factors (such as light, oxygen, and water) on the active substances of the core material, reducing the diffusion and evaporation of the core material to the environment, effectively improving the performance level of the core material, and reducing the potential toxicity risks to the environment and humans. Although plant-based substances have the advantages of low toxicity, safety, environmental protection, and low residue, their active ingredients are unstable to light and heat, easy to decompose, and have a short effective period. In addition, botanical pesticides are not non-toxic. While they are effective in preventing and controlling forest pests, their safety to non-target organisms has gradually attracted people's attention. The application of microencapsulation technology can effectively solve this shortcoming and is conducive to the research and development and promotion of botanical pesticides. Therefore, in order to avoid the toxic effects of plant secondary metabolites on target organisms due to external environments such as light and temperature, or to reduce their own toxicity to non-target organisms, it is urgent to use microencapsulation technology to encapsulate plant secondary metabolites to control herbivorous insects. Summary of the invention

[0004] The purpose of the present invention is to provide a botanical pesticide microcapsule and a preparation method that can effectively control the American white moth, so as to solve the problem that the toxic effects of plant secondary metabolites on target organisms are reduced due to external environments such as light and temperature, and the toxicity of plant secondary metabolites to non-target organisms is reduced.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A botanical pesticide microcapsule capable of effectively preventing and controlling the American white moth. The microcapsule components are: esculetin as a core material, gelatin as a wall material, the wall ratio is 1:5, and the microcapsule is placed in a sodium sulfate solution and mixed evenly.

[0007] Preferably, the concentration of the sodium sulfate solution is 20%, the reaction temperature is 50-55° C., and the stirring speed is 500-600 r / min.

[0008] A method for preparing botanical pesticide microcapsules capable of effectively controlling gypsy moths comprises the following steps:

[0009] S1. Stir the gelatin evenly in a water bath to completely dissolve it into a light yellow clear solution, and cool it naturally to room temperature to obtain a gelatin solution;

[0010] S2, placing the aesculetin powder in the gelatin solution obtained in step S1, adjusting the solution to be acidic, and stirring until the aesculetin powder is completely dissolved to obtain aesculetin suspension;

[0011] S3, preparing two concentrations of sodium sulfate solution, namely sodium sulfate mixed solution and sodium sulfate diluted solution;

[0012] S4, slowly adding the sodium sulfate mixture prepared in step S3 to the aesculetin suspension obtained in step S2, and continuously stirring under hot bath conditions to form capsules;

[0013] S5, the capsule formed in step S4 is continuously stirred in an ice water bath, and a 3-fold sodium sulfate dilution prepared in step S3 is added, and the mixture is stirred sufficiently to allow gelatin to be completely deposited on the aesculetin, thereby obtaining a gelatin-aesculetin mixed solution;

[0014] S6. Add glutaraldehyde to the gelatin-frasucrose mixed solution obtained in step S5, stir and solidify it continuously, then let it stand to sink, pour off the supernatant, rinse and filter it with deionized water for several times, wash it with anhydrous ethanol solution and filter it for several times, dry it naturally, and finally obtain the frasucrose microcapsule powder for standby use.

[0015] Preferably, the stirring device in step S1 is a magnetic stirrer, the stirring speed is 200-220 rpm, the stirring time is 10-15 min, the water bath temperature is 50-55° C., and the mass concentration of the obtained gelatin solution is 3%.

[0016] Preferably, in step S2, an acetic acid solution with a volume fraction of 10% is used to adjust the pH value of the solution to 4-5, the stirring speed is 500-600 rpm, and the stirring time is 20-25 min.

[0017] Preferably, in step S3, the concentration of the sodium sulfate mixed solution is 30% to 35%, and the concentration of the sodium sulfate dilution solution is 11% to 15%.

[0018] Preferably, in step S4, the stirring speed is 500-600 rpm, the stirring time is 30-40 min, and the temperature of the hot bath is 50-55°C.

[0019] Preferably, in step S5, the temperature of the ice water bath is 1-10° C., the temperature of the sodium sulfate dilution is 15-20° C., the stirring speed is 500-600 rpm, and the stirring time is 1-1.5 h.

[0020] Preferably, in step S6, the concentration of glutaraldehyde is 5% to 10%, the volume of glutaraldehyde is 2% to 10% of the system solution, the solidification time is 2 to 3 hours, and the stirring condition is 1 to 1.5 hours.

[0021] Preferably, the number of filtrations in step S6 is 3 to 5 times, and the number of suction filtrations is 3 to 5 times.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) The aesculetin microcapsules with gelatin as the wall material of the present invention have good sustained release performance;

[0024] (2) The wall material of the microcapsule in the present invention is a natural polymer material, which is inexpensive and harmless to the environment;

[0025] (3) The surface of the aesculetin microcapsules in the present invention is relatively smooth, and the particle size distribution of the microcapsules is uniform;

[0026] (4) The toxicity of the aesculetin microcapsules to non-target organisms is significantly reduced;

[0027] (5) The process of the present invention is simple, easy to operate, and the reaction conditions are mild, which provides a good theoretical and material basis for the development of plant-derived pesticides and has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a scanning electron microscope image of the aesculetin microcapsule of the present invention;

[0029] Figure 2 This is a particle size analysis diagram of the aesculetin microcapsules of the present invention;

[0030] Figure 3 The infrared spectra of the aesculetin microcapsules (1), aesculetin (2) and gelatin (3) of the present invention;

[0031] Figure 4 is a thermogravimetric analysis diagram of aesculetin and aesculetin microcapsules of the present invention;

[0032] Figure 5 is a release rate diagram of aesculetin and aesculetin microcapsules of the present invention;

[0033] Figure 6 The figures are the survival curve (A) and body weight (B) of the larvae of the American white moth in the group treated with the aesculetin microcapsules of the present invention;

[0034] Figure 7 The figures are the survival curves of zebrafish treated with aesculetin of the present invention (A); the survival curves of zebrafish treated with aesculetin microcapsules (B); the survival curves of corymboptera treated with aesculetin (C); and the survival curves of corymboptera treated with aesculetin microcapsules (D);

[0035] Figure 8 The figure is a field test of the aesculetin microcapsule suspension of the present invention. The figure shows the weight (A) and mortality (B) of the 9th day larvae of the American white moth treated with the aesculetin microcapsule suspension. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] Embodiment 1:

[0038] See also Figures 1 to 8 As shown, a plant-derived pesticide microcapsule that can effectively control the American white moth has esculetin as the core material and gelatin as the wall material, and the core-to-wall ratio (W / W) is 1:5. The preparation method thereof is as follows:

[0039] (1) Preparation of gelatin solution: Weigh 0.9 g of gelatin, add 30 ml of distilled water, place on a magnetic stirrer and stir at 200 rpm in a 50°C water bath for 15 min until it dissolves into a light yellow clear solution. This is the gelatin solution.

[0040] (2) Weigh 0.18 g of esculetin powder and place it in a gelatin solution at room temperature, adjust the pH value of the solution to 4 with 10% by volume acetic acid solution, and stir at a speed of 500 r / min for 20 min until fully mixed to obtain an esculetin suspension;

[0041] (3) Preparation of 30% sodium sulfate solution: Weigh 30 g of sodium sulfate and use a 100 mL volumetric flask and distilled water to make up to volume and dissolve by ultrasonication to obtain a 30% sodium sulfate solution;

[0042] (4) Preparation of 11.5% sodium sulfate solution: Weigh 11 g of sodium sulfate and use a 100 mL volumetric flask and distilled water to make up to volume and dissolve by ultrasonication to obtain an 11% sodium sulfate solution;

[0043] (5) Coagulation: The suspension of aesculetin was placed on a magnetic stirrer at 500 r / min, and 30% sodium sulfate solution was slowly added, and stirred for 30 min in a hot bath at 50°C until capsules were formed. Subsequently, in an ice water bath (5°C), 11% sodium sulfate dilution at a temperature of 15°C and a volume more than 3 times that of the system solution (200 mL) was added under continuous stirring, and stirred continuously at 500 r / min for 1 h to ensure that gelatin was completely deposited on aesculetin.

[0044] (6) Solidification, granulation and drying: Add 10 mL of 5% glutaraldehyde and solidify for 2 h (stirring during the process), let it stand until it sinks, decant the supernatant, rinse with distilled water for 3 times, continue to wash with ethanol solution and filter for 3 times, dry naturally, and finally obtain the quinoline microcapsule powder.

[0045] In this embodiment, the specific requirements of each raw material are shown in Table 1 below:

[0046]

[0047]

[0048] Table 1

[0049] The microscopic examination diagram shows that the aesculetin microcapsules prepared under the optimal conditions have good capsule appearance, uniform particle size, smooth surface, and basically no adhesion. The particle size distribution instrument observation found that the average particle size of the aesculetin microcapsules was 183.59μm, and the microcapsule particle size diagram showed that the left and right sides were relatively symmetrical, and no larger microcapsules appeared ( Figure 1 and Figure 2 ).

[0050] In the infrared spectrum of aesculetin microcapsules, it can be observed that the -1 、1628.33cm -1 、1442.84cm -1、1399.32cm -1 、873.65cm -1 and 560.09cm -1 A characteristic vibration absorption peak appears at . This is similar to the characteristic vibration absorption peak of aesculetin, but the vibration amplitude of aesculetin microcapsules is significantly weakened. The vibration absorption peak of aesculetin microcapsules in the infrared spectrum is basically consistent with the vibration absorption peak and vibration amplitude of gelatin ( Figure 3 ).

[0051] When the temperature is between 95.37℃ and 168.73℃, the total weight of aesculetin decreases by 2.77% ( Figure 4 A). When the temperature reaches 216.7℃~399.16℃, the weight loss rate of esculetin is as high as 64.81%, and the weight loss rate is maintained at 0.65mg / min -1 ( Figure 4 B). When the temperature was between 158.66℃ and 468.77℃, the weight loss rate of the aesculetin microcapsules was 63.96%, and the weight loss rate was maintained at 0.32 mg / min. -1 ( Figure 4 A and B).

[0052] Compared with the cumulative release rate of 21.5% of aesculetin microcapsules in aqueous solution in 2 days, the cumulative release rate of aesculetin in aqueous solution in 2 days was as high as 62.1%. On the 3rd day, aesculetin was completely released in water, while the complete release of aesculetin microcapsules required 11 days ( Figure 5 ).

[0053] Embodiment 2:

[0054] Indoor gastric toxicity test:

[0055] 2.5g of quinoline microcapsules were added to 10ml of distilled water to make a microcapsule suspension. Subsequently, 10ml of the microcapsule suspension was added to 90g of artificial feed. After stirring evenly, artificial feed containing 2.5% quinoline microcapsules was successfully prepared. The artificial feed containing quinoline microcapsules and untreated artificial feed were fed to the larvae of the third-instar American white moth that had molted for no more than 12h. After microcapsule treatment, the mortality rate and weight of the American white moth larvae in each group were counted on the 2nd, 4th, 6th and 8th days. When measuring the weight, one larva was a replicate, with a total of 100 replicates. When measuring the mortality rate, 4 replicates were set, with 25 larvae in each replicate. The results showed that compared with the control group, the treatment with 2.5% aesculetin microcapsules could significantly inhibit the weight of the larvae of the American moth on the 2nd, 4th, 6th and 8th days after treatment, with the weight inhibition rates being 25.38%, 27.87%, 60.13% and 74.67% respectively ( Figure 6B). Compared with the control group, the cumulative mortality of larvae treated with aesculetin microcapsules after 8 days was significantly increased (59%) ( Figure 6 A). The reason why the scutellarin microcapsules cause the death of the nymphalids and the weight inhibition rate gradually increases is that: the protective effect of the capsule material of the scutellarin microcapsules, the substances in the capsule core begin to penetrate and slowly release after spraying, the capsule material effectively blocks the adverse effects of the external environment on it, and the effect of the microcapsules is a slow release process. After the nymphalids feed on it, it can continue to produce the effect, making the drug effect more lasting and the insecticidal effect better.

[0056] Embodiment three:

[0057] Biosafety test of aesculetin microcapsules:

[0058] 20mg, 100mg, 500mg, 1000mg and 2500mg of esculetin microcapsules were placed in 1L of water (tap water, aerated for more than 5 days) to prepare 20mg / L, 100mg / L, 500mg / L, 1000mg / L and 2500mg / L treatment solutions. 300 healthy zebrafish with an average body length of about 3cm and a body weight of 1.0-1.2g were selected for the biosafety test of esculetin microcapsules. These zebrafish had been pre-raised in the laboratory for 8 days before the experiment. The zebrafish were kept under the conditions of a 12h / 12h light-dark cycle, a water temperature of 22-26℃, and fed once a day. Zebrafish were not fed 24h before the biosafety test. Zebrafish were then placed in different concentrations of esculetin microcapsule treatment solutions. Zebrafish placed in water (tap water, aerated for 5 days) were used as the control group. There were 4 replicates for each concentration, with 10 zebrafish in each replicate. The symptoms of zebrafish poisoning and the number of deaths were observed starting 2 hours after the experiment, and the statistics were kept for a total of 96 hours. In addition, a 2.5% quinoline suspension and quinoline microcapsule suspension were prepared with distilled water. Three-year-old caterpillars that had been molting for 24 hours were selected, and the prepared quinoline suspension and microcapsule suspension were sprayed on the back of the caterpillars (natural enemies of the American white moth) using a spray bottle. The treatment with distilled water was used as the control group. The mortality rate of caterpillars was observed every day for a total of 4 days. There were 3 replicates in each group, and each replicate consisted of 20 caterpillars. The results showed that the LC50 of zebrafish treated with quinoline was 541.00 mg / L ( Figure 7 A). However, the LC50 of zebrafish treated with esculetin microcapsules on the 4th day was only 901.00 mg / L ( Figure 7 B). The survival rate of the stink bugs treated with 2500 mg / L aesculetin microcapsules on the 4th day was significantly lower than that of the stink bugs treated with 2500 mg / L aesculetin on the 4th day, which were 95% and 86.7%, respectively ( Figure 7C and D). Refer to the classification standard of pesticide toxicity to fish in my country's "Chemical Pesticide Environmental Safety Evaluation Test Guidelines": LC50>10.0mg / L is a low-toxic pesticide. And refer to the acute toxicity classification standard of the natural enemy of arthropods, Trichogramma, and follow the toxicity (or risk) level classification standard in the informative appendix of the "Chemical Pesticide Environmental Safety Evaluation Test Guidelines" (Table 2).

[0059] Table 2 Toxicity or risk level classification standards of natural enemy Trichogramma:

[0060] Toxicity (or risk level) <![CDATA[96h-LC 50 (mg / L)]]> Low toxicity (low risk) <![CDATA[LC 50 >200]]> Poisoning (medium risk) <![CDATA[20<LC 50 <200]]> Highly toxic (high risk) <![CDATA[0.5<LC 50 <20]]> Highly toxic (extremely high risk) <![CDATA[LC 50 ≤0.5]]>

[0061] Table 2

[0062] The results showed that the microencapsulation of quinoline significantly reduced the toxicity of quinoline to non-target organisms, and also proved the biosafety of quinoline microcapsules to non-target organisms.

[0063] Embodiment 4:

[0064] This design is specifically used in many fields such as forestry protection, urban greening and organic agriculture. Its wall material design of natural polymer materials not only ensures the slow release of pesticides and improves the durability of drug efficacy, but also reduces toxicity to soil, water sources and non-target organisms (such as birds, insects, etc.), which meets the high requirements of modern agriculture for ecological safety.

[0065] In addition, as consumers become more aware of food safety and environmental protection, the market demand for green pesticides is growing. As a new type of plant-based pesticide, quinoline microcapsules have a simple production process, relatively low cost, and are easy to industrialize, which will strongly promote the expansion of the green pesticide market. As a green, efficient and environmentally friendly pesticide formulation, it can not only effectively solve the threat of harmful insects such as the American white moth to forestry resources, but also reduce the negative impact on the ecosystem and promote the development of sustainable agriculture and forestry.

[0066] Further, the insecticidal activity of esculetin microcapsules was verified in the field:

[0067] A 2.5% suspension of quinoline microcapsules was prepared with distilled water. The quinoline microcapsule suspension was sprayed on the leaves of Koelreuteria paniculata in the wild and on the backs of the third-instar larvae of the American white moth on the leaves. The spray volume was set at a ratio of 10 larvae to 1 mL of quinoline microcapsule suspension. The treatment sprayed with distilled water was used as the control group. Subsequently, the branches were covered with 80-mesh insect-proof nets to prevent the larvae from escaping. The mortality of the larvae in each group was counted on the 3rd, 6th and 9th days after spraying, and the weight of the larvae was counted on the 9th day. When measuring the weight, one larva was a replicate, with a total of 300 replicates. When measuring the mortality rate, 6 replicates were set, with 50 larvae in each replicate. The results showed that the mortality rate of the larvae in the quinoline microcapsule treatment group was significantly higher than that of the control group in each time period. The cumulative mortality rates of the American white moth larvae treated with 2.5% quinoline microcapsule suspension were 13.7% and 50.67% on the 3rd and 9th days, respectively ( Figure 8 B). The cumulative mortality of untreated larvae on the 3rd and 9th days was 3% and 5%, respectively ( Figure 8 B). On the 9th day after treatment, the body weight of the larvae in the group treated with aesculetin microcapsules was significantly lower than that in the control group, with a body weight inhibition rate of 72.3% ( Figure 8 A). This directly clarifies that plant-derived pesticide microcapsules with quinoline as the active ingredient can be used for efficient, safe and environmentally friendly prevention and control of the American white moth.

[0068] As can be seen from the above, the aesculetin microcapsules with gelatin as the wall material of the present invention have good sustained release performance;

[0069] The wall material of the microcapsule is natural polymer material, which is cheap and harmless to the environment;

[0070] The surface of the esculetin microcapsules is relatively smooth, and the particle size distribution of the microcapsules is uniform;

[0071] The toxicity of aesculetin microcapsules to non-target organisms was significantly reduced;

[0072] The invention has simple process, easy operation and mild reaction conditions, provides a good theoretical and material basis for the development of plant-derived pesticides and has good application prospects.

[0073] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0074] In the drawings of the embodiments disclosed in the present invention, only the structures related to the embodiments disclosed in the present invention are involved, and other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present invention can be combined with each other.

[0075] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A botanical pesticide microcapsule capable of effectively controlling the gypsy moth, characterized in that: The microcapsule components are: esculetin as the core material, gelatin as the wall material, the wall ratio is 1:5, and the microcapsules are placed in a sodium sulfate solution and mixed evenly.

2. The botanical pesticide microcapsule capable of effectively controlling the gypsy moth according to claim 1, characterized in that: The concentration of the sodium sulfate solution is 20%, the reaction temperature is 50-55° C., and the stirring speed is 500-600 r / min.

3. A method for preparing a botanical pesticide microcapsule capable of effectively controlling the gypsy moth according to any one of claims 1 to 2, characterized in that: The following steps are involved: S1. Stir the gelatin evenly in a water bath to completely dissolve it into a light yellow clear solution, and cool it naturally to room temperature to obtain a gelatin solution; S2, placing the aesculetin powder in the gelatin solution obtained in step S1, adjusting the solution to be acidic, and stirring until the aesculetin powder is completely dissolved to obtain aesculetin suspension; S3, preparing two concentrations of sodium sulfate solution, namely sodium sulfate mixed solution and sodium sulfate diluted solution; S4, slowly adding the sodium sulfate mixture prepared in step S3 to the aesculetin suspension obtained in step S2, and continuously stirring under hot bath conditions to form capsules; S5, the capsule formed in step S4 is continuously stirred in an ice water bath, and a 3-fold sodium sulfate dilution prepared in step S3 is added, and the mixture is stirred sufficiently to allow gelatin to be completely deposited on the aesculetin, thereby obtaining a gelatin-aesculetin mixed solution; S6. Add glutaraldehyde to the gelatin-frasucrose mixed solution obtained in step S5, stir and solidify it continuously, then let it stand to sink, pour off the supernatant, rinse and filter it with deionized water for several times, wash it with anhydrous ethanol solution and filter it for several times, dry it naturally, and finally obtain the frasucrose microcapsule powder for standby use.

4. The method for preparing a botanical pesticide microcapsule capable of effectively controlling the gypsy moth according to claim 3, characterized in that: The stirring device in step S1 is a magnetic stirrer, the stirring speed is 200-220 rpm, the stirring time is 10-15 min, the water bath temperature is 50-55° C., and the mass concentration of the obtained gelatin solution is 3%.

5. The method for preparing a botanical pesticide microcapsule capable of effectively controlling the gypsy moth according to claim 3, characterized in that: In step S2, an acetic acid solution with a volume fraction of 10% is used to adjust the pH value of the solution to 4-5, the stirring speed is 500-600 rpm, and the stirring time is 20-25 min.

6. The method for preparing a botanical pesticide microcapsule capable of effectively controlling the gypsy moth according to claim 3, characterized in that: In step S3, the concentration of the sodium sulfate mixed solution is 30% to 35%, and the concentration of the sodium sulfate dilution solution is 11% to 15%.

7. The method for preparing a botanical pesticide microcapsule capable of effectively controlling the gypsy moth according to claim 3, characterized in that: In step S4, the stirring speed is 500-600 rpm, the stirring time is 30-40 min, and the temperature of the hot bath is 50-55°C.

8. The method for preparing a botanical pesticide microcapsule capable of effectively controlling the gypsy moth according to claim 3, characterized in that: In step S5, the temperature of the ice water bath is 1-10° C., the temperature of the sodium sulfate dilution is 15-20° C., the stirring speed is 500-600 rpm, and the stirring time is 1-1.5 h.

9. The method for preparing a botanical pesticide microcapsule capable of effectively controlling the gypsy moth according to claim 3, characterized in that: In step S6, the concentration of glutaraldehyde is 5% to 10%, the volume of glutaraldehyde is 2% to 10% of the system solution, the solidification time is 2 to 3 hours, and the stirring condition is 1 to 1.5 hours.

10. The method for preparing a botanical pesticide microcapsule capable of effectively controlling the gypsy moth according to claim 3, characterized in that: In step S6, the number of filtrations is 3 to 5 times, and the number of suction filtrations is 3 to 5 times.

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