Pesticide composition for preventing and treating root-knot nematode and application method thereof
By combining abamectin formulations with water hyacinth extract, the problems of high toxicity and significant environmental impact of existing pesticides in controlling root-knot nematodes have been solved, achieving high-efficiency control and environmental benefits at low doses.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HENAN DECI YANGNONG BIOTECH CO LTD
- Filing Date
- 2026-02-05
- Publication Date
- 2026-05-12
AI Technical Summary
Existing pesticides are highly toxic and have a significant impact on soil and the environment when controlling root-knot nematodes. Furthermore, their effectiveness is not significant with long-term use, making it difficult to meet the demand for environmentally friendly and efficient pesticides that reduce dosage.
A pesticide combination of abamectin formulation and water hyacinth water extract was used. By applying 2% abamectin liquid formulation diluted 5000 times and water hyacinth water extract diluted 10 times through root irrigation, the dosage of abamectin was reduced while the control effect was improved.
It significantly reduced the amount of abamectin used, achieved effective control of root-knot nematodes, reduced soil and environmental pollution, promoted plant growth, and had environmental benefits.
Smart Images
Figure CN122004259A_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of biopesticide technology. Specifically, this application provides a pesticide combination for controlling root-knot nematodes and its application method. Background Technology
[0002] Root-knot nematodes (Meloidogyne) are highly specialized omnivorous plant pathogenic nematodes that can damage a variety of crops, including tobacco, cucumber, peanut, radish, and cabbage. Affected plants develop weak root systems and white root galls, severely impacting crop growth and agricultural production.
[0003] Root-knot nematodes live in shallow soil and are difficult to see with the naked eye. They usually overwinter as eggs and invade the tender root tissues of plants in spring as second-instar larvae. Deep tillage and other soil treatments can alleviate root-knot nematode disease, but the effect is not significant. In production, pesticides such as abamectin and thiazophos are commonly used by mixing or drenching. With technological advancements and regulatory changes, the toxicity and soil damage of these pesticides have become relatively low, but long-term use still has adverse effects on soil, surrounding water environment, and beneficial insects. There remains a continuous need in this field to reduce pesticide use.
[0004] Water hyacinth (Pontederia crassipes / Eichhornia crassipes), also known as water lettuce, is native to Central and South America and has medicinal, environmental, feed, and fertilizer value. After being introduced to my country in the early 20th century, it proliferated in many waterways due to its low environmental requirements and lack of competition, causing serious problems such as waterway blockage, harm to native flora and fauna, and eutrophication. Currently, the main method for dealing with water hyacinth outbreaks is harvesting. However, since utilization for feed and papermaking requires costly and specialized processing, the primary use of harvested water hyacinth is currently limited to the production of organic fertilizer. The ecological competitiveness of water hyacinth largely stems from its components that combat microalgae and insects; therefore, developing pesticides using its extracts is an effective way to fully utilize it. Summary of the Invention
[0005] On the one hand, this application provides a pesticide combination for controlling root-knot nematodes, the pesticide combination comprising an abamectin formulation and a water extract of water hyacinth.
[0006] Furthermore, the avermectin preparation is a 2-10% avermectin liquid preparation.
[0007] Furthermore, the avermectin preparation is a 2% avermectin liquid preparation.
[0008] Furthermore, the preparation method of the water hyacinth extract is as follows:
[0009] (1) After draining the water from the water hyacinth, crush it to obtain water hyacinth fragments;
[0010] (2) Add water containing 2-4 times the wet weight of water hyacinth fragments to water, and stir at 85-95℃ for 1-3 hours to obtain an extract mixture;
[0011] (3) Filter the extracted mixture and centrifuge at 800-1200g for 5-15 minutes to obtain water extract of water hyacinth.
[0012] Furthermore, the preparation method of the water hyacinth extract is as follows:
[0013] (1) After draining the water from the water hyacinth, crush it to obtain water hyacinth fragments;
[0014] (2) Add water containing three times the wet weight of the water hyacinth fragments to water and stir at 90°C for 2 hours to obtain an extract mixture;
[0015] (3) Filter the extracted mixture and centrifuge at 1000g for 10 minutes to obtain water extract of water hyacinth.
[0016] Furthermore, the nematode is the southern root-knot nematode.
[0017] On the other hand, this application provides a method for controlling southern root-knot nematodes in crops, the method comprising applying a 5000-fold diluted 2% abamectin liquid preparation and a 10-fold diluted water extract of water hyacinth through root irrigation.
[0018] Furthermore, the preparation method of the water hyacinth extract is as follows:
[0019] (1) After draining the water from the water hyacinth, crush it to obtain water hyacinth fragments;
[0020] (2) Add water containing 2-4 times the wet weight of water hyacinth fragments to water, and stir at 85-95℃ for 1-3 hours to obtain an extract mixture;
[0021] (3) Filter the extracted mixture and centrifuge at 800-1200g for 5-15 minutes to obtain water extract of water hyacinth.
[0022] Furthermore, the preparation method of the water hyacinth extract is as follows:
[0023] (1) After draining the water from the water hyacinth, crush it to obtain water hyacinth fragments;
[0024] (2) Add water containing three times the wet weight of the water hyacinth fragments to water and stir at 90°C for 2 hours to obtain an extract mixture;
[0025] (3) Filter the extracted mixture and centrifuge at 1000g for 10 minutes to obtain water extract of water hyacinth.
[0026] Furthermore, the method includes applying 150-350 mL of a 2% abamectin liquid preparation diluted 5000 times and 100-200 mL of water hyacinth water extract diluted 10 times to the roots of each plant.
[0027] Furthermore, the crop in question is chili pepper.
[0028] The abamectin can be a liquid or solid formulation, and can be in the form of emulsion, water-in-oil emulsion, microcapsule, etc. Those skilled in the art can dilute and adjust the dosage according to the instructions and common knowledge of pesticide application.
[0029] Those skilled in the art can also adjust the dosage according to the formulation (e.g., solid formulation), the crop (such as cucumber, tobacco, etc., which may be affected by root-knot nematodes), and the method of application (fertigation, mixing, etc.).
[0030] Beneficial effects:
[0031] In the technical solution of this application, water hyacinth is a low-cost waste (only requiring salvage and transportation), and the extraction method is simple and easy to implement. When used in conjunction with abamectin, it can significantly reduce the dosage / concentration of abamectin, achieving significant environmental benefits, while also promoting plant growth. Attached Figure Description
[0032] Figure 1 Typical results of the insecticidal activity experiment are shown (the left part shows typical images of surviving nematodes in the control group, and the right part shows typical images of nematodes that became stiff and died after the drug was applied; the unclear camera annotation information is covered with a white box).
[0033] Figure 2 Typical results of the chili plant experiment are shown (the left part shows the typical situation of weak seedling roots due to the influence of nematodes in the control group, and the right part shows the seedling root condition after pesticide application; the unclear camera annotation information is covered with a white box).
[0034] Figure 3 The values are root node inhibition rate, root weight, and leaf chlorophyll content for various parameters in Example 3.
[0035] Detailed Implementation Example 1: Preparation of Aqueous Extract of Water Hyacinth
[0036] The water hyacinth samples were collected from a body of water in Wuhan.
[0037] Fresh water hyacinth samples were drained and pulverized, then purified water (3 times the wet weight of the pulverized samples) was added. The mixture was extracted at 90°C with stirring for 2 hours. After filtration, the water hyacinth was centrifuged at 1000g for 10 minutes to obtain the water hyacinth water extract. The water extract can be further concentrated or prepared into powder using methods such as rotary evaporation or freeze-drying.
[0038] Example 2: Nematode-killing effect of water hyacinth extract and its compound pesticide
[0039] Basic experimental methods for nematicidal activity:
[0040] A large number of second-instar root-knot nematode larvae (Southern Root-Knot Nematode, Meloidogyne incognita) were obtained by selecting appropriate egg sacs and hatching them uniformly. The larvae were prepared into a suspension of approximately 200 larvae / mL. Approximately 100 larvae and 1 mL of drug solution or distilled water were added to each well of a plate (3 replicates). The larvae were incubated at 25°C for 48 hours, and the mortality rate was observed and calculated (rigid, immobile larvae were considered dead). The mortality rate was corrected by subtracting the mortality rate of the control group to calculate the actual effect of the drug: (Drug group mortality rate - Control group mortality rate) / (1 - Control group mortality rate) × 100%.
[0041] The nematicidal effect of the water extract of *Eichhornia crassipes* was determined using a 1000-fold dilution of 2% abamectin (commercially available emulsion) as a control. The results are shown in Table 1.
[0042] Table 1. Nematode-killing effect of water extract from water hyacinth
[0043]
[0044] The results showed that the nematicidal effect of the water extract of water hyacinth was very limited, with an inhibitory effect of only about 15% even when using the concentrated solution.
[0045] Subsequently, the applicant attempted to test the nematicidal effect of water hyacinth extract combined with different drugs (1 mL of nematode suspension of approximately 100 nematodes + 1 mL of each drug solution), and the results are shown in Table 2.
[0046] Table 2. Nematode-killing effects of water hyacinth extract and different drug combinations.
[0047]
[0048] The results showed that the aqueous extract of water hyacinth had virtually no effect on the efficacy of thiazophos. However, it exhibited a very significant synergistic effect with avermectin, especially at low concentrations. A 10-fold dilution of the water hyacinth aqueous extract, combined with a 5000-fold dilution (considering the increased volume, this can be considered a 10000-fold dilution, 10 times lower than the conventional concentration), still achieved an effect similar to direct application of a 1000-fold dilution. Based on these results, the water hyacinth aqueous extract should have the effect of increasing avermectin uptake or enhancing its neurotoxic physiological effects.
[0049] Example 3: Actual crop application effect
[0050] Laboratory-grown chili seedlings (screw peppers) were transplanted to an experimental plot in southern China severely affected by root-knot nematodes. One week after transplanting, the following treatments were administered via root drenching: 200 mL of abamectin 1000X (Group 1); 200 mL of abamectin 5000X (Group 2); 100 mL of water hyacinth water extract 10X (Group 3); 200 mL of abamectin 5000X + 100 mL of water hyacinth water extract 10X (Group 4); and 200 mL of distilled water as a control. Each treatment had 50 plants. Three weeks after root drenching, the root knot inhibition rate (number of root knots in control - number of root knots treated / number of root knots in control), average root weight, and average chlorophyll content (average of the top three leaves) were measured.
[0051] The results are as follows Figure 1-3 As shown, when combined with a 10X diluted water extract of water hyacinth, the dosage / concentration of abamectin can be reduced by 5 times, while still achieving similar effects to standard application methods. In terms of chlorophyll content, the water extract of water hyacinth also has a certain growth-promoting effect (the figure shows a large number of axes, making it less obvious; group 1 has a chlorophyll content of approximately 3.0 mg / g, and group 4 has approximately 3.4 mg / g).
Claims
1. A pesticide combination for controlling root-knot nematodes, characterized in that, The pesticide combination includes abamectin formulation and water hyacinth extract.
2. The pesticide combination according to claim 1, wherein the abamectin formulation is a 2-10% abamectin liquid formulation.
3. The pesticide combination according to claim 2, wherein the abamectin formulation is a 2% abamectin liquid formulation.
4. The method for preparing the water hyacinth extract according to any one of claims 1-3 is as follows: (1) After draining the water from the water hyacinth, crush it to obtain water hyacinth fragments; (2) Add water containing 2-4 times the wet weight of water hyacinth fragments to water, and stir at 85-95℃ for 1-3 hours to obtain an extract mixture; (3) Filter the extracted mixture and centrifuge at 800-1200g for 5-15 minutes to obtain water extract of water hyacinth.
5. The method for preparing the water hyacinth extract according to claim 4 is as follows: (1) After draining the water from the water hyacinth, crush it to obtain water hyacinth fragments; (2) Add water containing three times the wet weight of the water hyacinth fragments to water and stir at 90°C for 2 hours to obtain an extract mixture; (3) Filter the extracted mixture and centrifuge at 1000g for 10 minutes to obtain water extract of water hyacinth.
6. A method for controlling southern root-knot nematodes in crops, characterized in that, The method includes root irrigation with a 2% avermectin liquid preparation diluted 4000-6000 times and a 10-fold diluted water extract of water hyacinth.
7. The method according to claim 6, wherein the preparation method of the water hyacinth extract is as follows: (1) After draining the water from the water hyacinth, crush it to obtain water hyacinth fragments; (2) Add water containing 2-4 times the wet weight of water hyacinth fragments to water, and stir at 85-95℃ for 1-3 hours to obtain an extract mixture; (3) Filter the extracted mixture and centrifuge at 800-1200g for 5-15 minutes to obtain water extract of water hyacinth.
8. The method according to claim 6, wherein the preparation method of the water hyacinth extract is as follows: (1) After draining the water from the water hyacinth, crush it to obtain water hyacinth fragments; (2) Add water containing three times the wet weight of the water hyacinth fragments to water and stir at 90°C for 2 hours to obtain an extract mixture; (3) Filter the extracted mixture and centrifuge at 1000g for 10 minutes to obtain water extract of water hyacinth.
9. The method according to any one of claims 6-8, wherein the method comprises applying 150-350 mL of a 2% abamectin liquid preparation diluted 5000 times and 100-200 mL of water hyacinth water extract diluted 10 times to the roots of each plant.
10. The method according to any one of claims 6-9, wherein the crop is chili pepper.