Application of compound of acinetobacter HUNAN-1, dinotefuran and nitenpyram in prevention and treatment of sogatella furcifera

Abstract

The invention relates to an application of a compound of a sogatella furcifera symbiotic bacterium acinetobacter HUNAN-1, dinotefuran and nitenpyram in prevention and treatment of sogatella furcifera. According to the invention, on the basis that the HUNAN-1 strain bacterial liquid has the effect of killing sogatella furcifera, through compounding with the pesticides dinotefuran and nitenpyram, the effect of enhancing the insecticidal effect of the compound agent is realized, and the usage amount of the pesticides is reduced. The invention can delay the generation of pest resistance to drugs and reduce the pollution of pesticides to the environment, and has a good application prospect.

Description

Technical Field

[0001] The present invention belongs to the technical field of agricultural pest control, and specifically relates to the application of the compound of Acinetobacter HUNAN-1, dinotefuran, and nitenpyram in the control of the white-backed planthopper. Background Art

[0002] Acinetobacter is a Gram-negative coccus bacillus, widely distributed in the natural environment with strong adaptability, and can survive in humid environments. It can cause various human diseases, including bloodstream infections, pneumonia, urinary tract infections, and gastroenteritis. Acinetobacter bacteria also have strong drug resistance, can accumulate various drug resistance mechanisms, and produce strains that are resistant to all commercially available antibiotics. In addition, Acinetobacter is also a symbiotic bacterium in insects such as Spodoptera frugiperda and planthoppers, and has a lethal effect on nematodes.

[0003] The white-backed planthopper Sogatella furcifera (Horváth) belongs to the Delphacidae family of the Hemiptera order, and is one of the main pests of rice. By sucking the phloem sap of rice, it causes the rice to turn yellow and wither, seriously affecting the safe production of rice and causing significant economic losses. At present, chemical pesticides are still the main means of controlling the white-backed planthopper, and the frequent use of pesticides has exacerbated the emergence of pest drug resistance. Research shows that the white-backed planthopper shows moderate resistance to imidacloprid and thiamethoxam, and high resistance to chlorpyrifos and buprofezin. Therefore, it has become particularly urgent to explore green control methods for the white-backed planthopper, and there is an urgent need to provide a green, environmentally friendly and efficient control method for the white-backed planthopper. Summary of the Invention

[0004] To solve the existing problems, the present invention discovers that the symbiotic bacterium Acinetobacter soli HUNAN-1 in the white-backed planthopper and the compounding of pesticides can reduce the use of pesticides, thereby delaying the emergence of pest drug resistance and being environmentally friendly.

[0005] One object of the present invention is to provide the application of Acinetobacter soli HUNAN-1, a symbiotic bacterium of the white-backed planthopper, in the control of the white-backed planthopper.

[0006] One object of the present invention provides the compound application of Acinetobacter soli HUNAN-1, a symbiotic bacterium of the white-backed planthopper, and dinotefuran in pest control, including the following steps:

[0007] 1) Add the Acinetobacter of the white-backed planthopper to LB liquid medium for enrichment and culture;

[0008] 2) Add sterile water to the bacterial solution to disperse it evenly and mix it with the dinotefuran medicinal solution;

[0009] 3) Attach the solution to the rice seedlings by the rice seedling dipping method.

[0010] One of the purposes of the present invention is to provide a compound application of Acinetobacter soli HUNAN-1, a symbiotic bacterium of the white-backed planthopper, and nitenpyram in pest control, including the following steps:

[0011] 1) Add Acinetobacter of the white-backed planthopper to LB liquid medium for enrichment and culture;

[0012] 2) Add sterile water to the bacterial solution to disperse it evenly and mix it with the nitenpyram medicament solution;

[0013] 3) Attach the solution to the rice seedlings by the rice seedling dipping method.

[0014] Specifically, the present invention provides a composition for controlling the white-backed planthopper, including effective active components A and B. Among them, the active ingredient A is Acinetobacter HUNAN-1, and its preservation number is CCTCC M20241953; the active ingredient B is dinotefuran or nitenpyram.

[0015] Furthermore, when the active ingredient B is dinotefuran, the ratio of Acinetobacter HUNAN-1 to dinotefuran is 2:1; when the active ingredient B is nitenpyram, the ratio of Acinetobacter HUNAN-1 to nitenpyram is (1-2):(5-1).

[0016] Furthermore, the concentration of Acinetobacter HUNAN-1 is 1.54×10 7 -1.09×10 8 CFU / mL, preferably 2.79×10 7 CFU / mL; the concentration of dinotefuran is 2.11-2.78 mg / L, preferably 2.42 mg / L; the concentration of nitenpyram is 1.28-1.82 mg / L, preferably 1.54 mg / L.

[0017] Furthermore, the dosage form of the composition includes wettable powder, suspension, water dispersible granule, emulsion in water or emulsifiable concentrate.

[0018] The present invention also provides a method for controlling the white-backed planthopper, using any one of the above compositions to treat rice.

[0019] Furthermore, attach the composition to the rice seedlings by the rice seedling dipping method.

[0020] The present invention also provides the application of the combination of Acinetobacter HUNAN-1 and dinotefuran or nitenpyram in the preparation of a preparation for controlling the white-backed planthopper, and the preservation number of Acinetobacter HUNAN-1 is CCTCC M20241953.

[0021] Further, the ratio of Acinetobacter HUNAN-1 to dinotefuran is 2:1, or the ratio of Acinetobacter HUNAN-1 to nitenpyram is (1-2):(5-1).

[0022] Further, the concentration of Acinetobacter HUNAN-1 is 1.54×10 7 -1.09×10 8 CFU / mL, preferably 2.79×10 7 CFU / mL; the concentration of dinotefuran is 2.11-2.78 mg / L, preferably 2.42 mg / L; the concentration of nitenpyram is 1.28-1.82 mg / L, preferably 1.54 mg / L.

[0023] The present invention also provides the application of any one of the above-mentioned compositions or methods in controlling Sogatella furcifera.

[0024] The present invention combines the symbiotic bacterium Acinetobacter HUNAN-1 of Sogatella furcifera with dinotefuran and nitenpyram. The process is simple and the effect is remarkable. On the premise of ensuring the insecticidal effect, the amount of pesticides used is reduced, and the generation of pest resistance is delayed, which is of great significance for realizing the sustainable control of pests. Specific Embodiments

[0025] The following examples are only used to illustrate the technical solutions of the present invention more clearly, so they are only examples and cannot be used to limit the protection scope of the present invention. It should be noted that unless otherwise specified, the technical terms or scientific terms used in this application should be the commonly understood meanings by those skilled in the art to which the present invention belongs. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in this technical field. Unless otherwise specified, the reagents and materials used in the following examples are all commercially available.

[0026] The inventor's prior patent (CN119120304A) has recorded Acinetobacter soli HUNAN-1, which was deposited at the China Center for Type Culture Collection on September 11, 2024, with the deposit number: CCTCC M20241953.

[0027] Example 1 Toxicity determination of the bacterial liquid of Acinetobacter soli HUNAN-1 strain against Sogatella furcifera

[0028] The Acinetobacter soli HUNAN-1 strain was inoculated into LB liquid medium and cultured in a shaker at 37°C and 200 r / min. Using the plate counting method, the concentration of the bacterial suspension was adjusted to 10 9 、108 、10 7 、10 6 、10 5 CFU / mL. The rice seedling dipping method was used to determine the virulence against the white-backed planthopper: Rice seedlings with good growth conditions and the same size were selected. The rice seedlings were dipped in the bacterial solution for 90 s, air-dried, and the roots of the rice seedlings were wrapped with absorbent cotton to keep the roots moist. The rice seedlings were placed in plastic cups, and 20 well-grown 3rd instar nymphs of the white-backed planthopper were placed in each plastic cup, and the cups were sealed with a gauze net. Each treatment was repeated 4 times. The control was the LB liquid medium without inoculating the strain. The treated nymphs were cultured in an incubator at 27 ± 1 °C, relative humidity (RH) 80 ± 5%, and a photoperiod of 16:8 h (L:D). The death of the nymphs was checked every 24 h, and the corrected mortality was cumulatively counted for 120 h.

[0029] Table 1 Virulence of Acinetobacter sp. HUNAN-1 against 3rd instar nymphs of the white-backed planthopper for 72 h

[0030]

[0031] The results showed that after 72 h of treatment with the bacterial solution, the rice seedling dipping method had good insecticidal effects against the white-backed planthopper, and the LC 50 value was 4.79×10 7 CFU / mL (Table 1). It was proved that the strain had stomach toxicity against the white-backed planthopper.

[0032] Example 2 Determination of the virulence of dinotefuran and nitenpyram against 3rd instar nymphs of the white-backed planthopper for 72 h

[0033] The tested dinotefuran and nitenpyram technicals were diluted with acetone into a stock solution of 1000 mg·L -1 . Then, they were serially diluted with ultrapure water into 5 different concentration gradients of 10 mg·L -1 , 5 mg·L -1 , 2.5 mg·L -1 , 1.25 mg·L -1 , 0.625 mg·L -1 , and ultrapure water was used as the blank control. Rice seedlings with good growth conditions and the same size were selected. The rice seedlings were dipped in the solution for 90 s, air-dried, and the roots of the rice seedlings were wrapped with absorbent cotton to keep the roots moist. The white-backed planthopper nymphs were inoculated in the same way as in Example 1, and the death of the nymphs was checked every 24 h.

[0034] Table 2 Virulence of dinotefuran and nitenpyram against 3rd instar nymphs of the white-backed planthopper for 72 h

[0035]

[0036]

[0037] The results showed that after treating the 3rd instar nymphs of Sogatella furcifera with the rice seedling immersion method for 72 h, the LC 50 value of dinotefuran was 2.42 mg / L, and the LC 50 value of nitenpyram was 1.54 mg / L (Table 2). The results indicated that S. furcifera was more sensitive to nitenpyram.

[0038] Example 3 Co-toxicity factor of Acinetobacter sp. HUNAN-1 and dinotefuran against the 3rd instar nymphs of Sogatella furcifera after compounding

[0039] The bacterial suspension and the medicament solution at the concentration of dinotefuran LC 50 were separately selected, and then mixed at volume ratios of 5:1, 2:1, 1:1, 1:2, and 1:5. The insecticidal activities of the mixed agents were determined by the rice seedling immersion method, and the death of nymphs was checked every 24 h. The synergistic effect was evaluated by the co-toxicity factor method to determine the synergistic effect of each combination.

[0040] Co-toxicity factor = (observed mortality of the mixture - theoretical mortality of the mixture / theoretical mortality of the mixture) × 100. A co-toxicity factor > 20 indicates a synergistic effect of the compound agent; ≤ -20 indicates an antagonistic effect; between -20 and 20 indicates an additive effect.

[0041] Table 3 Co-toxicity factor of Acinetobacter sp. HUNAN-1 and dinotefuran against the 3rd instar nymphs of Sogatella furcifera after compounding

[0042]

[0043] The results showed that when the Acinetobacter sp. HUNAN-1 bacterial suspension was compounded with dinotefuran and the volume ratio of the strain to dinotefuran was 2:1, the co-toxicity factor was greater than 20, indicating that the compounding of the two had a synergistic effect against S. furcifera. It could be compounded as an insecticide against S. furcifera, reducing the amount of pesticides used on the premise of ensuring the insecticidal effect and delaying the emergence of pest resistance.

[0044] Example 4 Co-toxicity factor of Acinetobacter sp. HUNAN-1 and nitenpyram against the 3rd instar nymphs of Sogatella furcifera after compounding

[0045] The bacterial suspension and the medicament solution at the concentration of nitenpyram LC 50 were separately selected, and then mixed at volume ratios of 5:1, 2:1, 1:1, 1:2, and 1:5. The insecticidal activities of the mixed agents were determined by the rice seedling immersion method, and the death of nymphs was checked every 24 h. The synergistic effect was evaluated by the co-toxicity factor method to determine the synergistic effect of each combination.

[0046] The results showed that when the Acinetobacter sp. HUNAN-1 bacterial solution was compounded with nitenpyram, both had a synergistic effect when the volume ratio of the bacterial solution to nitenpyram was 2:1, 1:1, 1:2, or 1:5 (see Table 4).

[0047] Table 4 Co-toxicity factors of the mixture of Acinetobacter sp. HUNAN-1 and nitenpyram against the 3rd instar nymphs of the white-backed planthopper

[0048]

[0049] The results showed that when the Acinetobacter sp. HUNAN-1 bacterial solution was compounded with nitenpyram, and the volume ratio of the strain to nitenpyram was 1:2, 1:5, 1:1, or 2:1, the co-toxicity factors were all greater than 20, indicating that the ratio of (1-2):(5-1) had a synergistic effect against the white-backed planthopper. It could be compounded as an insecticide against the white-backed planthopper, reducing the amount of pesticides used while ensuring the insecticidal effect and delaying the emergence of pest resistance.

[0050] The above specific embodiments have described the implementation of the present invention in detail. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the claims and technical concept of the present invention, various simple modifications and changes can be made to the technical solution of the present invention, and these simple variations all belong to the protection scope of the present invention.

Claims

1. A composition for controlling white-backed planthopper, characterized in that: The invention comprises effective active components A and B, wherein the active component A is Acinetobacter HUNAN-1; and the active component B is dinotefuran or nitenpyram.

2. The composition according to claim 1, characterized in that When the active ingredient B is dimethoate, the ratio of Acinetobacter HUNAN-1 to dimethoate is 2:1; when the active ingredient B is nitenpyram, the ratio of Acinetobacter HUNAN-1 to nitenpyram is (1-2): (5-1).

3. The composition according to any one of claims 1-2, characterized in that The concentration of Acinetobacter HUNAN-1 was 1.54×10 7 -1.09×10 8 CFU / mL, preferably 2.79×10 7 CFU / mL; the concentration of dinotefuran is 2.11-2.78 mg / L, preferably 2.42 mg / L; the concentration of nitenpyram is 1.28-1.82 mg / L, preferably 1.54 mg / L.

4. The composition according to any one of claims 1-2, characterized in that The dosage form of the composition includes wettable powder, suspension, water dispersible granule, aqueous emulsion or emulsifiable concentrate.

5. A method for controlling white-backed planthoppers, characterized in that: The composition according to any one of claims 1 to 4 is used to treat rice.

6. The method according to claim 5, characterized in that The composition is attached to the rice seedlings by dipping the rice seedlings.

7. The application of the combination of Acinetobacter HUNAN-1 and dinotefuran or nitenpyram in the preparation of preparations for controlling white-backed planthoppers.

8. The use according to claim 7, characterized in that: The ratio of Acinetobacter HUNAN-1 to dimethoate is 2:1, or the ratio of Acinetobacter HUNAN-1 to nitenpyram is (1-2): (5-1).

9. The use according to any one of claims 7-8, characterized in that: The concentration of Acinetobacter HUNAN-1 was 1.54×10 7 -1.09×10 8 CFU / mL, preferably 2.79×10 7 CFU / mL; the concentration of dinotefuran is 2.11-2.78 mg / L, preferably 2.42 mg / L; the concentration of nitenpyram is 1.28-1.82 mg / L, preferably 1.54 mg / L.

10. Use of the composition according to any one of claims 1 to 4 or the method according to any one of claims 5 to 6 in controlling white-backed planthoppers.

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