A bactrocera dorsalis nanosynergist, and a preparation method and application thereof

Abstract

The application discloses a Bactrocera dorsalis nanometer synergist and a preparation method and application thereof. The Bactrocera dorsalis nanometer synergist is prepared by compounding 5Z-7-oxozeaenol and a nanometer carrier HLDP with a pesticide; wherein, the 5Z-7-oxozeaenol and the nanometer carrier HLDP have structural formulas as shown in formula I and formula II. The preparation method of the Bactrocera dorsalis nanometer synergist comprises the following steps: mixing the pesticide, the 5Z-7-oxozeaenol and the nanometer carrier HLDP, and incubating to obtain the Bactrocera dorsalis nanometer synergist. The use method of the Bactrocera dorsalis nanometer synergist comprises the following steps: preparing the Bactrocera dorsalis nanometer synergist into a nanometer synergist solution, adding sucrose, and feeding the Bactrocera dorsalis. The Bactrocera dorsalis nanometer synergist has a low particle size, can significantly increase the insecticidal effect of chlorfenapyr, and is helpful for efficient prevention and control of the Bactrocera dorsalis; the Bactrocera dorsalis nanometer synergist has broad-spectrum synergism, and can enhance the insecticidal effect on the Bactrocera dorsalis when being compounded with other pesticides.

Description

Technical Field

[0001] This invention belongs to the field of pest control technology, and relates to a nano-synergist for the oriental fruit fly, its preparation method, and its application. Background Technology

[0002] Oriental fruit fly Bactrocera dorsalis The oriental fruit fly (Hendel) belongs to the order Diptera and is a global quarantine pest that damages various fruits and vegetables. Adult oriental fruit flies lay their eggs inside the fruit; the larvae hatch and feed on the pulp, causing the fruit to fall and rot, severely impacting fruit quality and yield. Due to its wide host range, high reproductive rate, strong flight ability, and rapid migration, the oriental fruit fly is difficult to control. However, with the widespread adoption of chemical control, the oriental fruit fly has gradually developed pesticide tolerance. Traditional insecticide spraying is ineffective because of the fly's ability to evade it through rapid flight, and it also leads to pesticide residues in the fruit.

[0003] To address the increasing resistance of oriental fruit flies to pesticides, the use of inhibitors or synergists is a widespread practice. For example, inhibitors of common detoxification enzymes can enhance the effectiveness of certain insecticides. Commonly used synergists include inhibitors of cytochrome P450 oxidases such as pyrethroids (PBO), pyrethroids, and pyrethroids; inhibitors of carboxylesterases such as defoliant (DEF) and triphenyl phosphate (TPP); and inhibitors of glutathione S-transferases such as diethyl maleate (DEM). Targeting specific genes identified as target genes for oriental fruit fly synergistic effects with specific inhibitors to enhance pest control is a crucial approach to controlling this pest.

[0004] However, how to link inhibitors with pesticides for controlling the oriental fruit fly, making the oriental fruit fly sensitive to pesticides, thereby reducing the pesticide dosage while improving its killing effect on the oriental fruit fly, and thus avoiding the problem of pesticide resistance from long-term use, is a technical challenge in this field. This application aims to solve this technical problem. Summary of the Invention

[0005] The purpose of this invention is to provide a nano-synergist for the oriental fruit fly, its preparation method, and its application.

[0006] The nano-synergist for the oriental fruit fly of this invention can improve the sensitivity of the oriental fruit fly to insecticides and increase the insecticidal effect of the insecticides.

[0007] The nano-enhancer for the oriental fruit fly of this invention has a low particle size, which can significantly increase the insecticidal effect of chlorfenapyr and help to effectively control the oriental fruit fly.

[0008] This invention provides a nano-synergist for the oriental fruit fly, which is formulated by compounding an insecticide with 5Z-7-Oxozeaenol and the nanocarrier HLDP; wherein the structural formulas of 5Z-7-Oxozeaenol and the nanocarrier HLDP are shown in Formula I and Formula II below: .

[0009] In the aforementioned oriental fruit fly nano-synergist, the mass ratio of the insecticide to the nanocarrier HLDP can be 1:1~3, preferably 1:2, and the final concentration of 5Z-7-Oxozeaenol can be 20~30μM, specifically 25μM, 20~25μM or 20~25μM.

[0010] In the above-mentioned oriental fruit fly nano-synergist, the insecticide is selected from at least one of chlorfenapyr, lambda-cyhalothrin, emamectin benzoate, and spinosad. The oriental fruit fly nano-synergist of the present invention can have an insecticidal synergistic effect on the above-mentioned insecticides.

[0011] The present invention also provides a method for preparing the above-mentioned oriental fruit fly nano-synergist, comprising the following steps: mixing the insecticide, 5Z-7-Oxozeaenol and the nanocarrier HLDP, and incubating to obtain the oriental fruit fly nano-synergist.

[0012] In the above-mentioned oriental fruit fly nano-enhancer, the incubation time can be 5 min to 10 min.

[0013] In this invention, the incubation temperature is room temperature, specifically 10~30℃.

[0014] The citrus fruit fly nano-synergist described in this invention is used in the preparation of insecticides for controlling citrus fruit flies.

[0015] The present invention further provides a method for using the above-mentioned oriental fruit fly nano-synergist, comprising the following steps: preparing the oriental fruit fly nano-synergist into a nano-synergist solution, adding sucrose, and feeding it to oriental fruit flies.

[0016] In the above method, the concentration of the nano-synergist solution can be 0.5 mg / L to 80 mg / L, and the concentration of sucrose added to the nano-synergist solution can be 3% to 10%, specifically 5%, 5% to 10%, or 5% to 10%.

[0017] The present invention has the following beneficial effects: 1. The present invention provides a nano-synergist for the oriental fruit fly, which combines 5Z-7-Oxozeaenol and the nanocarrier HLDP with an insecticide. It has a low particle size and can significantly increase the insecticidal effect of chlorfenapyr, thus contributing to the efficient control of the oriental fruit fly.

[0018] 2. The nano-synergist of this invention has broad-spectrum synergistic effects and can enhance the insecticidal effect against the oriental fruit fly when combined with other insecticides.

[0019] 3. The nano-synergist based on the inhibitor 5Z-7-Oxozeaenol and the nanocarrier HLDP, provided by this invention, and combined with insecticides, can effectively reduce the tolerance of oriental fruit fly to pesticides and improve the control effect of oriental fruit fly. Attached Figure Description

[0020] Figure 1 The particle size and morphology of the acaricide nano-synergist for the fruit fly citrus; Figure 1 In this context, A represents the particle size of the citrus fruit fly acaricide nano-synergist. Figure 1 In this context, B represents the morphology of the citrus fruit fly miticide nano-synergist.

[0021] Figure 2 A schematic diagram of a citrus fruit fly feeding on a nano-enhancing agent.

[0022] Figure 3 The mortality rate of oriental fruit flies at different time points after feeding on chlorfenapyr nano-enhancer.

[0023] Figure 4 The mortality rate of oriental fruit flies after feeding on nano-synergists formulated with different pesticides. Detailed Implementation

[0024] Unless otherwise specified, the experimental methods used in the following examples are conventional methods.

[0025] Unless otherwise specified, all materials and reagents used in the following examples are commercially available.

[0026] Those skilled in the art should understand that modifications or substitutions to the details and form of the present invention can be made without departing from the spirit and scope of the invention, but all such modifications and substitutions fall within the protection scope of the present invention.

[0027] The reagents and materials used in the following examples are as follows: Chlorfenapyr, lambda-cyhalothrin, and emamectin benzoate were all purchased from Shanghai Aladdin Reagent Co., Ltd., with product numbers C1421591, C707249, and E396669, respectively. Spinosad was purchased from Beijing Mairuida Technology Co., Ltd., with the abbreviations CHL, CYH, EB, and SPI for chlorfenapyr, lambda-cyhalothrin, emamectin benzoate, and spinosad, respectively. 5Z-7-Oxozeaenol was purchased from Shanghai Maclean Biochemical Technology Co., Ltd., with product number Z880005.

[0028] In the following examples, both the lambda-bearing strain (RES) and the wild-type strain (WT) of lambda-bearing flies were obtained from the laboratory of Li Zhihong, China Agricultural University (Liu et al., A novel potential nAChR variation and the upregulation of CYP304A1 contribute to resistance against lambda-cyhalothrin and spinosadin Bactrocera dorsalis . Entomologia Generalis. 44 (5) (2024) 1321-1330).

[0029] The preparation method of the HLDP nanocarrier in the following examples includes the following steps: (1) Take 100 mg 1 Butanol, 6.16 g ε-caprolactone (ε-CL) and 310 mg stannous octanoate (Sn(Oct)2) were mixed and incubated in an oil bath at 90 °C for 9 h. Then, 30 mL of dichloromethane (DCM) was added and the mixture was deposited in cold methanol. After filtration, the intermediate product PCL was obtained. (2) Take 3 g 2 Bromoisobutyryl bromide (BIBB), 30 mL of tetrahydrofuran (THF), and 4 g of triethanolamine (TEA) were added dropwise to 3 g of PCL solution to react. Then, methanol was added to quench the reaction. After quenching, the resulting precipitate was collected by filtration to obtain the intermediate product PCL. Br; (3) Take 100 mg PCL Br and 0.87 g of dimethylaminoethyl methacrylate (DMAEMA) were dissolved in a mixed solvent of 2 mL tetrahydrofuran and 15 mg CuBr. 37 mg of pentamethyldiethylenetriamine (PMDETA) was added to the solution, and then polymerization was carried out in an oil bath at 65 °C. (4) After the polymerization reaction stops, the reaction system is treated with liquid nitrogen bath, then heated to room temperature, and then dialyzed with water and freeze-dried to obtain a white powder product, which is the nanomaterial (hereinafter referred to as HLDP). HLDP is an amphiphilic block copolymer, which is used to prepare different concentrations of HLDP nanocarriers in the following examples.

[0030] Example 1 The preparation method of the ciprofloxacin nanocomposite includes the following steps: Take 10 μL of 10 g / L ciprofloxacin (final concentration 10 mg / L), 10 μL of 20 g / L HLDP nanocarrier (final concentration 20 mg / L), and 25 μL of 10 mM 5Z-7-Oxozeaenol (final concentration 25 μM), respectively, and then add them to a test tube containing 10 mL of ultrapure water and mix well. Incubate at room temperature (25℃, the same below) for 5 min to prepare the ciprofloxacin nanocomposite, which is used for measuring the particle size of the composite.

[0031] Example 2 The preparation method of the acaricide nanosynergist for the citrus fruit fly includes the following steps: Take 10 μL of 10 g / L acaricide (final concentration 10 mg / L), 10 μL of 20 g / L HLDP nanocarrier (final concentration 20 mg / L), and 25 μL of 10 mM 5Z-7-Oxozeaenol (final concentration 25 μM), respectively, and then add them to a test tube containing 10 mL of ultrapure water with 5% sucrose. Mix well and incubate at room temperature (25℃) for 5 min to obtain the acaricide nanosynergist for the citrus fruit fly.

[0032] Example 3 The preparation method of the nano-synergist of high-efficiency cyhalothrin for the oriental fruit fly includes the following steps: Take 80 μL of 10 g / L high-efficiency cyhalothrin (final concentration 80 mg / L), 80 μL of 20 g / L HLDP nanocarrier (final concentration 160 mg / L), and 25 μL of 10 mM 5Z-7-Oxozeaenol (final concentration 25 μM), respectively, and then add them to a test tube containing 10 mL of ultrapure water with 5% sucrose. Mix well and incubate at room temperature for 5 min to obtain the nano-synergist of high-efficiency cyhalothrin for the oriental fruit fly.

[0033] Example 4 The preparation method of nano-synergist of emamectin benzoate in the oriental fruit fly includes the following steps: Take 5 μL of 1 g / L emamectin benzoate (final concentration 0.5 mg / L), 0.5 μL of 20 g / L HLDP nanocarrier (final concentration 1 mg / L), and 25 μL of 10 mM 5Z-7-Oxozeaenol (final concentration 25 μM), respectively, and then add them to a test tube containing 10 mL of ultrapure water with 5% sucrose. Mix well and incubate at room temperature for 5 min to obtain the nano-synergist of emamectin benzoate in the oriental fruit fly.

[0034] Example 5 The preparation method of spinosad nano-synergist for oriental fruit fly includes the following steps: Take 10 μL of 1 g / L spinosad (final concentration 1 mg / L), 1 μL of 20 g / L HLDP nanocarrier (final concentration 2 mg / L), and 25 μL of 10 mM 5Z-7-Oxozeaenol (final concentration 25 μM), respectively, and then add them to a test tube containing 10 mL of ultrapure water with 5% sucrose. Mix well and incubate at room temperature for 5 min to obtain the spinosad nano-synergist for oriental fruit fly.

[0035] Example 6 The nano-synergists prepared in the above examples were subjected to the following characterization or effect determination experiments: 1. Morphological characteristics The particle size and morphology of the citrus fruit fly miticide nanocomposite prepared in Example 1 were determined using a laser particle size analyzer and a scanning electron microscope. The specific steps are as follows: 8 µL of chlorfenapyr nanocomposite was dropped onto a silicon wafer, air-dried at room temperature, and sputtered with a thin gold layer to enhance conductivity before imaging.

[0036] High-resolution cold field scanning electron microscope: Hitachi S-4800, Japan.

[0037] Laser particle size analyzer: NanoBrook 90Plus PALS, Brookhaven Instruments, USA.

[0038] Scanning electron microscopy reveals that its morphology consists of clustered particles, such as... Figure 1 As shown in Figure A. The average particle size of the citrus fruit fly miticide nanocomposite prepared in Example 1, measured using a nanoparticle size analyzer, was approximately 139.5 nm. This was repeated three times. Figure 1 As shown in B.

[0039] 2. Evaluation of the synergistic effect of acaricide nano-synergist for fruit fly citrus citrus To prepare the citrus fruit fly miticide nano-synergist mentioned in Example 2 of this invention, CHL solution, CHL / HLDP solution, and 5Z7O / HLDP solution with the same final concentration as the citrus fruit fly miticide nano-synergist prepared in Example 2 of this invention were also prepared. All these solutions contained 5% sucrose. 2 mL of each solution was added to plastic fruit fly tubes containing paper towels. Ten female and ten male citrus fruit flies were placed in each tube. The tube openings were plugged with cotton balls. Three tubes were treated with each solution. The mortality rate of the citrus fruit flies was recorded every 12 hours. Figure 2 As shown. Survival test results are as follows. Figure 3 As shown, at the working concentration, feeding with 5Z-7-Oxozeaenol and HLDP had no significant effect on the survival rate of the oriental fruit fly. CHL / HLDP significantly increased the mortality rate of the oriental fruit fly compared to feeding with chlorfenapyr alone. However, after feeding with the chlorfenapyr nano-synergist CHL / 5Z7O / HLDP, the mortality rate exceeded 80% after 48 hours, demonstrating a significant synergistic effect in control.

[0040] 3. Evaluation of the synergistic effect of nano-synergists on other pesticides for the fruit fly citrus fruit fly. The *Bacteroides citrinum* nano-synergist mentioned in Examples 3, 4, and 5 of this invention was prepared. Simultaneously, CYH / HLDP, EB / HLDP, and SPI / HLDP solutions with the same final concentrations as those prepared in Examples 3, 4, and 5 were also prepared, all containing 5% sucrose. 2 mL of each solution was added to plastic tubes containing paper towels. Ten female and ten male *Bacteroides citrinum* flies were placed in each tube, and the tube openings were plugged with cotton balls. Three tubes were treated with each solution, and the mortality rate of the *Bacteroides citrinum* flies was recorded after 24 hours. Example 3 used a lambda-cyhalothrin-resistant strain of *Bacteroides citrinum* flies, while Examples 4 and 5 used wild-type strains. Figure 4 As shown in Figure A, the high-efficiency cyhalothrin nano-synergist exhibits a significant synergistic effect in cyhalothrin-resistant strains, with an enhancement of approximately 20%. This indicates that the nano-synergist with added 5Z-7-Oxozeaenol has a prominent effect on controlling resistant pests. Figure 4 China B and Figure 4 As shown in Figure C, the nano-synergist of emamectin benzoate significantly enhanced the insecticidal effect of emamectin benzoate in the wild-type strain of oriental fruit fly, with an enhancement of approximately 40%. At the same time, the nano-synergist of spinosad significantly enhanced the insecticidal effect of spinosad in the wild-type strain of oriental fruit fly, with an enhancement of approximately 30%.

[0041] These results demonstrate that 5Z-7-Oxozeaenol has a broad-spectrum synergistic effect on the insecticidal efficacy of pesticides.

[0042] This invention successfully prepared a broad-spectrum synergist for the citrus fruit fly (Bactrocera dorsalis) based on the nanocarriers HLDP and 5Z-7-Oxozeaenol. This significantly enhances the insecticidal effect of pesticides on the citrus fruit fly, and the feeding method also reduces pesticide residues in fruit production, making it more valuable for application. Overall, this invention is beneficial for the efficient and green control of the citrus fruit fly.

[0043] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments, all of which fall within the scope of the invention.

Claims

1. A Bactrocera dorsalis nanosynergist, characterized in that, This oriental fruit fly nano-synergist is formulated by combining 5Z-7-Oxozeaenol and the nanocarrier HLDP with an insecticide; wherein, the structural formulas of 5Z-7-Oxozeaenol and the nanocarrier HLDP are shown in Formula I and Formula II below: 。 2. The B. cucurbitae nanoscale synergist according to claim 1, characterized in that, In the aforementioned oriental fruit fly nano-enhancer, the mass ratio of the insecticide to the nanocarrier HLDP is 1:1~3, and the final concentration of 5Z-7-Oxozeaenol is 20~30 μM.

3. The B. cucurbitae nanosenseiibon according to claim 1 or 2, characterized in that, The insecticide is selected from at least one of chlorfenapyr, lambda-cyhalothrin, emamectin benzoate, and spinosad.

4. A method for preparing the oriental fruit fly nano-synergist according to any one of claims 1-3, comprising the following steps: mixing the insecticide, 5Z-7-Oxozeaenol and the nanocarrier HLDP, and incubating to obtain the oriental fruit fly nano-synergist.

5. The nano-synergist for the oriental fruit fly according to claim 4, characterized in that, The incubation time is 5 min to 10 min.

6. The use of the oriental fruit fly nano-synergist according to any one of claims 1-3 in the preparation of an insecticide for controlling oriental fruit flies.

7. A method of using the oriental fruit fly nano-synergist according to any one of claims 1-3, comprising the following steps: preparing the oriental fruit fly nano-synergist into a nano-synergist solution, adding sucrose, and feeding it to oriental fruit flies.

8. The method according to claim 7, characterized in that, The concentration of the nano-synergist solution is 0.5 mg / L to 80 mg / L, and the concentration of sucrose added to the nano-synergist solution is 3% to 10%.

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