Method for controlling spider mites by using bifenthrin-ethidimaz and plant essential oil

Abstract

The application belongs to the field of agricultural pest prevention and control and the field of pesticides, and provides a method for preventing and controlling spider mites by using bifenthrin-ethomec and plant essential oil, which comprises the following steps: (1) applying a plant essential oil solution or suspension to crops in need of prevention and control; and (2) applying a bifenthrin-ethomec suspension concentrate to the crops in need of prevention and control 12-36 hours after the application of the plant essential oil solution or suspension. According to the method, a low concentration of plant essential oil is applied in advance before the application of bifenthrin-ethomec, so that the dilution multiple of bifenthrin-ethomec can be greatly increased while the prevention and control effect is maintained.

Description

Technical Field

[0001] This application pertains to the fields of agricultural pest control and pesticides. Specifically, this application provides a method for controlling spider mites by combining bifenazate-etoxazole and plant essential oils. Background Technology

[0002] Spider mites, also known as red spider mites or white spider mites, include various species of mites in the genus Tetranychus. They mainly damage leaves by piercing and sucking, causing widespread harm to a large number of food crops and cash crops, and are one of the important targets for pest control.

[0003] Both bifenazate and etoxazole are triazole insecticides and acaricides. Bifenazate works by blocking electron transport in the mitochondria of mites, and is effective against mites at all growth stages. Etoxazole, on the other hand, works by inhibiting the formation of mite eggs and embryos or directly interfering with the molting stage of larvae. It is largely ineffective against adult mites, but has a very good inhibitory effect on larvae and eggs (LC50 as low as 0.1-2 μg / mL). In practice, the two are often used in combination, and several manufacturers offer bifenazate-etoxazole suspensions of approximately 40%, with a common dilution ratio of 2000-3000 times.

[0004] Biphenylhydrazine itself and its metabolite biphenylhydrazine-diazepine are both highly toxic and are substances of concern in food safety standards in various countries; while etoxazole's main harm lies in its toxicity to non-target organisms such as parasitic wasps and fish. Summary of the Invention

[0005] To reduce the human and environmental toxicity of bifenazate-etoxazole, increasing the dilution ratio as much as possible while ensuring efficacy is the most effective approach.

[0006] In response to the above situation, this application provides a method for controlling spider mites by combining bifenazate-etoxazole and plant essential oils, the method comprising:

[0007] (1) Apply plant essential oil solutions or suspensions to crops that require control;

[0008] (2) Apply bifenazate-ethoxazole suspension to crops that need control 12-36 hours after applying plant essential oil solution or suspension.

[0009] Furthermore, the spider mite is either two-spotted spider mite or carmine spider mite.

[0010] Further, step (2) involves applying bifenazate-ethoxazole suspension to the crop requiring control 24 hours after applying the plant essential oil solution or suspension.

[0011] Furthermore, the concentration of the plant essential oil solution or suspension is 3-8 μL / mL.

[0012] Furthermore, the concentration of the plant essential oil solution or suspension is 5 μL / mL.

[0013] Furthermore, the plant essential oil solution or suspension contains plant essential oil and Tween 80.

[0014] Furthermore, the concentration of Tween 80 in the plant essential oil solution or suspension is 0.05-2% w / v.

[0015] Further, step (2) involves applying a 8000-15000 times diluted solution of bifenazate-ethoxazole suspension to the crops requiring control 24 hours after applying the plant essential oil solution or suspension.

[0016] Further, step (2) involves applying a 10,000-15,000 times diluted solution of bifenazate-ethoxazole suspension to the crops requiring control 24 hours after applying the plant essential oil solution or suspension.

[0017] Further, step (2) involves applying a 10,000-fold diluted solution of bifenazate-ethoxazole suspension to the crop requiring control 24 hours after applying the plant essential oil solution or suspension.

[0018] Furthermore, the plant essential oil is chamomile essential oil.

[0019] Furthermore, the chamomile essential oil is chamomile essential oil prepared by steam distillation.

[0020] Furthermore, the total concentration of bifenazate and etoxazole in the bifenazate-etoxazole suspension is 35-45% w / v.

[0021] Furthermore, the mass ratio of bifenazate to etoxazole in the bifenazate-etoxazole suspension is 1-3:1.

[0022] Furthermore, the bifenazate-etoxazole suspension contains 25% w / v bifenazate and 15% w / v etoxazole.

[0023] The method described in this application is applicable to various crops that are susceptible to spider mite damage, including but not limited to field crops such as corn and cotton; fruit trees such as citrus and apples; vegetables such as melons and beans; and other cash crops such as cotton and tea.

[0024] Besides Tween 80, other surfactants or methods that help disperse essential oils in aqueous solutions (such as ultrasound, liposomes) are also applicable to the methods of this application. Those skilled in the art can select these reagents and methods according to the properties and concentration of the essential oils used and the requirements for reagent homogeneity.

[0025] Bifenazate-etoxazole in various concentrations (e.g., common 40%, 45%, 50%), ratios (e.g., bifenazate to etoxazole ratio of 1:1, 2:1, 3:1), and formulations (e.g. commonly used suspension concentrates) can be used in the pesticides or methods of this application. Those skilled in the art can adjust the dilution ratio and dosage according to the insect infestation, pest control requirements, pesticide residue requirements, etc.

[0026] When implementing the method of this application, plant essential oils and bifenazate-etoxazole can be provided separately, or both can be prepared into the same package and the usage method can be provided in the form of an instruction manual.

[0027] Beneficial effects:

[0028] The method described in this application, by applying a low concentration of non-toxic plant essential oil before applying bifenazate-etoxazole, can significantly increase the dilution ratio of bifenazate-etoxazole while maintaining the control effect, thus providing better protection for biosecurity, especially for food crops. Attached Figure Description

[0029] Figure 1 Statistics on the killing effects of different essential oils on two-spotted spider mites.

[0030] Figure 2 Statistics on the killing effect of bifenazate-etoxazole suspension combined with plant essential oils (essential oil group 1).

[0031] Figure 3 Statistics on the killing effect of bifenazate-etoxazole suspension combined with plant essential oils (essential oil group 2).

[0032] Figure 4 Statistics on the killing effect of bifenazate-etoxazole suspension combined with chamomile essential oil.

[0033] Detailed Implementation Example 1 Experimental Materials

[0034] Test reagent:

[0035] The 40w / v bisfenazate-etoxazole suspension (25% w / v bisfenazate, 15% w / v etoxazole) is a product manufactured by the applicant.

[0036] Sage essential oil, peppermint essential oil, cardamom essential oil, cinnamon essential oil, orange peel essential oil, and rose essential oil were purchased from Jilin Xinweite Pharmaceutical Technology Co., Ltd.

[0037] Jasmine essential oil, eucalyptus essential oil, and chamomile essential oil were prepared by the applicant using steam distillation.

[0038] Two-spotted spider mite tested:

[0039] The applicant collected and preserved samples from apple trees and cultured them on pea seedlings for testing.

[0040] Example 2: Leaf residue method for detecting the killing effect of pesticide on two-spotted spider mites

[0041] (1) Take pea leaves (medium size, about 4cm×1.5cm), immerse them in the solution (or control purified water) for 5 seconds, then take them out and air dry or use absorbent paper to dry the visible water on the surface;

[0042] (2) Select normal active female adult two-spotted spider mites and transfer them to the shade-dried pea leaves with a paintbrush, inoculating 30 mites per leaf;

[0043] (3) Place the inoculated leaves in a petri dish, with a layer of absorbent cotton soaked in water underneath to maintain moisture;

[0044] (4) Place the petri dish at 25℃ and 70% humidity for rearing, with a photocycle of 12 hours in light and 12 hours in darkness;

[0045] (5) Count the survival status of two-spotted spider mites on the leaves within the required time (the criterion for death is that the body and feet do not move when touched).

[0046] Five replicates were performed for each condition. A purified water control was included in each group of experiments. For experiments lasting less than 24 hours, a mortality rate of no more than 5% in the control was considered acceptable. For experiments lasting more than 24 hours, a mortality rate of no more than 10% in the control was considered acceptable. If any condition was not met, all experiments under that condition needed to be repeated.

[0047] Example 3: Killing performance of different plant essential oils against two-spotted spider mites

[0048] The applicant selected nine relatively inexpensive and common plant essential oils to test their killing performance against two-spotted spider mites.

[0049] The plant essential oil was prepared into a 5 μL / mL solution / suspension (ultrasonic-assisted dispersion) using a 0.1% w / v Tween-80 solution as the test solution, and tested according to the method in Example 2.

[0050] The results are as follows Figure 1 As shown, sage essential oil exhibited a significantly higher scavenging effect than other essential oils, reaching approximately 50% within 12 hours; peppermint, jasmine, and eucalyptus essential oils also showed some inhibitory effects; however, no significant scavenging effects were observed in cardamom, cinnamon, orange peel, rose, and chamomile essential oils.

[0051] Example 4: Combined use of bifenazate-etoxazole suspension with plant essential oils

[0052] 40% bifenazate-etoxazole suspension was diluted 2000 times (representing the usual dosage) and 10000 times (at this point the drug concentration is 40 μg / mL, corresponding to bifenazate at 25 μg / mL, which is far lower than the reported LC50 / effective dose of bifenazate against adult female two-spotted spider mites).

[0053] Add 0.1% w / v Tween-80 to a 10,000-fold diluted 40% bifenazate-etoxazole suspension to prepare 5 μL / mL solutions / suspensions of sage oil, peppermint oil, jasmine oil, and eucalyptus oil (ultrasonic-assisted dispersion), and test according to the method in Example 2.

[0054] The results are as follows Figure 2 As shown, Figure 2 The results showed that, compared with the results of Example 3 and the 10000X group, the combined use schemes did not achieve significant synergistic effects, and the effect of sage essential oil was even reduced after the combined use of pesticides.

[0055] because Figure 2 The results were unsatisfactory, so the applicant further expanded the range of essential oils (adding 0.1% w / v Tween-80 to a 10,000-fold diluted 40% bifenazate-etoxazole suspension to prepare a 5 μL / mL essential oil solution).

[0056] The results are as follows Figure 3 As shown, unexpectedly, chamomile essential oil, which has no obvious killing effect when used alone, achieved a significant synergistic effect when combined with bifenazate-etoxazole suspension. Although it was not as effective as the 2000X solution and sage essential oil, it was significantly improved compared to the 10000X group.

[0057] Example 5: Improvement of the combined use of bifenazate-etoxazole suspension and chamomile essential oil.

[0058] The applicant further attempted to apply bifenazate-etoxazole suspension separately from chamomile essential oil and sage essential oil, and then apply 10000X bifenazate-etoxazole suspension 24 and 48 hours after applying the essential oil (when applying bifenazate-etoxazole, the surviving spider mites were temporarily transferred to the untreated pea leaves with a brush, and then transferred back to the experimental leaves after soaking / drying).

[0059] The results are as follows Figure 4 The data shown (0h interval group number, data for drug diluted 2000X alone are taken from Example 4; 12h, 24h, and 48h in the figure are calculated based on the time of administration of bifenazate-etoxazole suspension).

[0060] Regarding the combined use of chamomile essential oil: it was found that applying the essential oil first and then the bifenazate-etoxazole suspension can further improve the effect, especially when the two are 24 hours apart. The effect is equal to or even slightly higher than that of using 2000X bifenazate-etoxazole suspension alone (approximately 67%, 85%, 93% vs. 57%, 79%, 89%). It is speculated that this phenomenon may be due to certain components in chamomile essential oil affecting certain metabolic or immune processes in the insect, resulting in increased sensitivity to bifenazate (and the possibility of etoxazole sensitivity cannot be ruled out).

[0061] Subsequently, a similar method was used to study the killing effect on *Tetranychus carmineus*, and the results are shown in Table 1. The trend shown is similar to that of *Tetranychus two-spotted*, indicating that this method is generally effective against *Tetranychus* genus and even *Tetranychidae* family.

[0062] Table 1. Killing effect of different pesticides on Tetranychus carmine (Tetranychus carmine n=150)

[0063] medicine Number of Tetranychus carminee deaths in 24 hours 48. Number of dead carmine spider mites Bifenazate-Etoxazole 2000X 95 / 150 113 / 150 Bifenazate-Etoxazole 10000X 34 / 150 58 / 150 5μL / mL chamomile essential oil 6 / 150 11 / 150 5 μL / mL chamomile essential oil, after 24 hours, bifenazate-etoxazole 10000X 86 / 150 121 / 150 Comparison 4 / 150 7 / 150

[0064] .

[0065] Citrus trees in the rapid population increase phase of red spider mite infestation were selected to verify the practical effect of the above scheme. The results showed that the above combined scheme achieved similar control efficacy as 2000X solution spraying (after only one application of bifenazate-etoxazole without other drugs, the changes in insect population density after 7 days of application of bifenazate-etoxazole alone and in combination were approximately +0.2% and -1.1%, respectively. Even when further diluted to 15000X, the change in insect population density was only 3.7%, with no significant difference). However, the dosage of bifenazate-etoxazole was reduced to 1 / 5 or even 1 / 8, which greatly improved the safety of agricultural products and reduced the requirements for post-treatment.

Claims

1. A method for controlling spider mites by combining bifenazate-etoxazole and plant essential oils, characterized in that, The method includes: (1) Apply plant essential oil solutions or suspensions to crops that require control; (2) Apply bifenazate-ethoxazole suspension to crops that need control 12-36 hours after applying plant essential oil solution or suspension.

2. The method according to claim 1, wherein the spider mite is a two-spotted spider mite or a carmine spider mite.

3. According to the method of claim 1, step (2) is to apply bifenazate-ethoxazole suspension to the crop that needs to be controlled 24 hours after applying the plant essential oil solution or suspension.

4. The method according to claim 1, wherein the concentration of the plant essential oil solution or suspension is 3-8 μL / mL.

5. The method according to claim 4, wherein the concentration of the plant essential oil solution or suspension is 5 μL / mL.

6. The method according to claim 4 or 5, wherein the plant essential oil is chamomile essential oil.

7. The method according to claim 1, wherein the total concentration of bifenazate and etoxazole in the bifenazate-etoxazole suspension is 35-45% w / v; and the mass ratio of bifenazate and etoxazole in the bifenazate-etoxazole suspension is 1-3:

1.

8. The method according to claim 6, wherein the bifenazate-etoxazole suspension contains 25% w / v bifenazate and 15% w / v etoxazole.

9. The method according to claim 3, wherein step (2) is to apply a 8000-15000 times diluted solution of bifenazate-ethoxazole suspension to the crop requiring control 24 hours after applying the plant essential oil solution or suspension.

10. The method according to claim 9, wherein step (2) is to apply a 10,000-15,000 times diluted solution of bifenazate-ethoxazole suspension to the crop requiring control 24 hours after the application of the plant essential oil solution or suspension.

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