Application of 2-hydroxy-3-methyl-2-cyclopentene-1-ketone in prevention and treatment of plant parasitic nematodes

Abstract

The invention discloses application of 2-hydroxy-3-methyl-2-cyclopentene-1-ketone in prevention and treatment of plant parasitic nematodes, and relates to the field of biological prevention and treatment of crop diseases, in particular to application of 2-hydroxy-3-methyl-2-cyclopentene-1-ketone in prevention and treatment of plant parasitic nematodes. The 2-hydroxy-3-methyl-2-cyclopentene-1-ketone is used for preventing and treating plant parasitic nematodes. When the concentration of the 2-hydroxy-3-methyl-2-cyclopentene-1-ketone is 0.8 g / L, the 24-hour corrected death rate of second-instar larvae of the meloidogyne incognita reaches 92.4%, the LC50 value is 0.29 g / L, the 48-hour corrected death rate reaches 99.15%, and the LC50 value is reduced to 0.047 g / L when the concentration of the 2-hydroxy-3-methyl-2-cyclopentene-1-ketone is 96 h. When the concentration of the 2-hydroxy-3-methyl-2-cyclopentene-1-ketone is 0.8 g / L, the 24-hour corrected death rate of second instar larvae of the soybean cyst nematode reaches 89.53%, the LC50 value is 0.39 g / L, the 48-hour corrected death rate reaches 92.64%, and the LC50 value is reduced to 0.019 g / L when the concentration of the 2-hydroxy-3-methyl-2-cyclopentene-1-ketone is 96 h.

Description

Technical Field

[0001] This invention relates to the field of biological control of crop diseases, and in particular to the application of 2-hydroxy-3-methyl-2-cyclopenten-1-one in the control of plant parasitic nematodes. Background Technology

[0002] Plant nematode diseases are plant diseases caused by the invasion and parasitism of plant-parasitic nematodes. They mainly occur in the roots of crops and are difficult to eradicate once they occur due to their hidden nature. Severe outbreaks can be devastating, especially with continuous planting of host plants. As the number of consecutive years of cropping increases, root-parasitic nematode diseases in these plants become particularly severe.

[0003] In production practice, chemical pesticides are mainly used for pest control. Although chemical control is effective, frequent use easily leads to pesticide resistance, reducing efficacy and causing serious pollution to the ecological environment. Pesticide residues also pose a significant threat to human health. With increasing awareness of environmental protection and food safety, green food is gaining more and more attention. The ban on highly toxic chemical pesticides is also leading to their withdrawal from the market. Currently, there is an urgent need for safe and efficient biological and bio-based agents to control soil-borne diseases in crops. Plants are rich in insecticidal and bacteriostatic bioactive substances that can resist pathogen invasion, are harmless to beneficial organisms, and are environmentally friendly. The development of new plant-derived pesticides using these substances is of great significance for the green control of nematode diseases. Summary of the Invention

[0004] The purpose of this invention is to solve the technical problems of chemical pesticide control, which can easily cause environmental pollution and pose potential risks to human health, and to provide an application of 2-hydroxy-3-methyl-2-cyclopenten-1-one in the control of plant parasitic nematodes.

[0005] Application of 2-hydroxy-3-methyl-2-cyclopenten-1-one in the control of plant parasitic nematodes, wherein the 2-hydroxy-3-methyl-2-cyclopenten-1-one is used to control plant parasitic nematodes.

[0006] The 2-hydroxy-3-methyl-2-cyclopenten-1-one is used as a nematicide to kill plant parasitic nematodes.

[0007] The 2-hydroxy-3-methyl-2-cyclopenten-1-one is used to control plant parasitic nematode diseases.

[0008] The plant parasitic nematodes mentioned are the southern root-knot nematode and the soybean cyst nematode.

[0009] The 2-hydroxy-3-methyl-2-cyclopenten-1-one, also known as methylcyclopentenolone (2-Hydroxy-3-methyl-2-cyclopenten-1-one), CAS number 80-71-7, has the molecular formula C6H8O2, a molecular weight of 112.13, a melting point of 106℃, and a boiling point of 170.05℃. It is a natural substance found in maple, angelica (family Prorocentrum), tobacco, and roasted coffee, exhibiting a maple-licorice flavor in diluted solutions. It is a white crystalline powder with an aroma similar to maple and angelica root, and is a good flavor enhancer and low-calorie sweetener, widely used in flavor formulations for food and beverages. The 2-hydroxy-3-methyl-2-cyclopenten-1-one in this invention is derived from a smoked flavoring primarily used for marinating grilled meats. Studies have shown that the mixture of smoked spices has a strong toxic effect on southern root-knot nematodes and soybean cyst nematodes, and also strongly inhibits the hatching of eggs from both nematodes. Further metabolomic analysis of the smoked spices revealed that 2-hydroxy-3-methyl-2-cyclopenten-1-one has excellent control effects against these two plant nematode diseases.

[0010] The beneficial effects of this invention are:

[0011] Experimental results showed that, in the toxicity test of 2-hydroxy-3-methyl-2-cyclopenten-1-one diluted to five concentrations against second-instar larvae of the southern root-knot nematode (Meloidogyne incognita), the 24-h corrected mortality rate reached 92.4% and the LC50 value was 0.29 g / L at a concentration of 0.8 g / L, the 48-h corrected mortality rate reached 99.15%, and the LC50 value decreased to 0.047 g / L at 96 h.

[0012] In a toxicity test of 2-hydroxy-3-methyl-2-cyclopenten-1-one against second-instar larvae of the soybean cyst nematode (Heterodera glycines, SCN), a concentration of 0.8 g / L resulted in a 24-h corrected mortality rate of 89.53% and an LC50 value of 0.39 g / L. The 48-h corrected mortality rate reached 92.64%, and the LC50 value decreased to 0.019 g / L at 96 h. Microscopic observation revealed that after 24 h of treatment with 2-hydroxy-3-methyl-2-cyclopenten-1-one, both types of nematodes exhibited a rigid state and showed no reaction upon mechanical contact, indicating their death. This demonstrates the strong toxicity of this plant-derived substance against both the southern root-knot nematode and the soybean cyst nematode.

[0013] In a pot experiment using 1000 second-instar larvae per plant as an inoculation dose for southern root-knot nematodes, drenching tomato roots with 1.6 g / L of 2-hydroxy-3-methyl-2-cyclopenten-1-one showed a control efficacy of 36.68% against the southern root-knot nematode, significantly higher than that of the conventional plant-derived preparation 1.6 g / L matrine (20.62% efficacy, P<0.05). Simultaneously, this substance had no adverse effects on tomato plant growth.

[0014] In a pot experiment using 1000 second-instar larvae per soybean cyst nematode inoculation dose, drenching soybean roots with 1.6 g / L of 2-hydroxy-3-methyl-2-cyclopenten-1-one showed a control efficacy of 66.09% against soybean cyst nematodes, significantly higher than that of the conventional plant-derived preparation 1.6 g / L matrine (21.43% efficacy, P<0.05). Simultaneously, this substance had no adverse effects on soybean plant growth. Attached Figure Description

[0015] Figure 1 This is a phenotypic diagram of the activity of second-instar larvae of *Strombocytoxinus chinensis* in southern China after 24 hours of untreated (control group) 2-hydroxy-3-methyl-2-cyclopenten-1-one.

[0016] Figure 2 This is a phenotypic diagram of the activity of second-instar larvae of *Strombocytoxinus chinensis* after 24 hours of treatment with 2-hydroxy-3-methyl-2-cyclopenten-1-one in Experiment 1.

[0017] Figure 3 This is a phenotypic diagram of the activity of second-instar soybean cyst nematode larvae in untreated (control group) soybeans for 24 hours in Experiment 2.

[0018] Figure 4 This is a phenotypic diagram of the activity of second-instar larvae of soybean cyst nematodes after 24 hours of treatment with 2-hydroxy-3-methyl-2-cyclopenten-1-one in Experiment 2. Detailed Implementation

[0019] The technical solution of the present invention is not limited to the specific embodiments listed below, but also includes any combination of the specific embodiments.

[0020] Specific Implementation Method 1: The application of 2-hydroxy-3-methyl-2-cyclopenten-1-one in the control of plant parasitic nematodes in this implementation method.

[0021] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that the 2-hydroxy-3-methyl-2-cyclopenten-1-one is used as a nematicide to kill plant parasitic nematodes. Everything else is the same as in Specific Implementation Method One.

[0022] Specific Implementation Method 3: This implementation method differs from Specific Implementation Method 1 or 2 in that the 2-hydroxy-3-methyl-2-cyclopenten-1-one is used to control plant parasitic nematode diseases. Everything else is the same as in Specific Implementation Method 1 or 2.

[0023] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that the plant parasitic nematodes are Southern Root-Knot Nematodes and Soybean Cyst Nematodes. Otherwise, it is the same as Specific Implementation Methods One to Three.

[0024] The following experiments were used to verify the effectiveness of the invention:

[0025] Experiment 1:

[0026] Toxicity experiments of 2-hydroxy-3-methyl-2-cyclopenten-1-one diluted to 5 concentrations against second-instar larvae of the southern root-knot nematode (Meloidogyne incognita):

[0027] Dilute pure 2-hydroxy-3-methyl-2-cyclopenten-1-one was prepared into dilute solutions with concentrations of 50 mg / L, 200 mg / L, 800 mg / L, 1600 mg / L, and 5000 mg / L using sterile water. Matrine (Mat) was used as a positive control, and sterile water served as a blank control (CK). 3 mL of each concentration of reagent was injected into 35 mm sterile culture dishes, followed by 50 μL of a suspension of approximately 200 J2 larvae (second instar) of *Symplocos spp.* root-knot nematodes. Three culture dishes were treated per batch and placed in a 28°C dark incubator. Nematode mortality was observed under a microscope at 24 h, 48 h, 72 h, and 96 h, and the corrected mortality rate for J2 larvae was calculated. The experiment was repeated twice.

[0028] Larval mortality rate (%) = Number of dead nematodes / Total number of tested larvae × 100;

[0029] Corrected larval mortality rate (%) = (Larval mortality rate in treatment group - Larval mortality rate in control group) / (1 - Larval mortality rate in control group) × 100

[0030] Experimental results showed that, in the toxicity test of 2-hydroxy-3-methyl-2-cyclopenten-1-one diluted to five concentrations against second-instar larvae of the southern root-knot nematode (Meloidogyne incognita), the 24-h corrected mortality rate reached 92.4% and the LC50 value was 0.29 g / L at a concentration of 0.8 g / L. The 24-h corrected mortality rate reached 99.15%, and the LC50 value decreased to 0.047 g / L at 96 h.

[0031] Table 1. Effects on the activity of second-instar larvae of the southern root-knot nematode.

[0032]

[0033] Experiment 2:

[0034] Toxicity test of 2-hydroxy-3-methyl-2-cyclopenten-1-one against second instar larvae of soybean cyst nematode (Heterodera glycines, SCN):

[0035] The method is the same as in Experiment 1, except that the southern root-knot nematode is replaced with soybean cyst nematode.

[0036] In a toxicity test of 2-hydroxy-3-methyl-2-cyclopenten-1-one against second-instar larvae of the soybean cyst nematode (Heterodera glycines, SCN), a concentration of 0.8 g / L resulted in a 24-h corrected mortality rate of 89.53% and an LC50 value of 0.39 g / L. The 48-h corrected mortality rate reached 92.64%, and the 48-h corrected mortality rate reached 100%. At 96 h, the LC50 value decreased to 0.019 g / L. Microscopic observation showed that after 24 h of treatment with 2-hydroxy-3-methyl-2-cyclopenten-1-one, both types of nematodes exhibited a rigid state and showed no reaction upon mechanical contact, indicating that the nematodes were dead. This demonstrates the strong toxicity of this plant-derived substance to both the southern root-knot nematode and the soybean cyst nematode.

[0037] Table 2 Effects on the activity of second-instar larvae of soybean cyst nematode

[0038]

[0039] Experiment 3:

[0040] Pot experiment on Southern Root-Knot Nematode inoculation dose of 1000 second-instar larvae / plant:

[0041] Sterilized and well-mixed sand (volume ratio 1:1) was placed in disposable seedling pots (diameter × height 8 × 12 cm), and three surface-sterilized tomato seeds (Zhongshu 4 variety) were sown in each pot. One week after seed germination, one healthy seedling was retained in each pot. Two weeks after sowing, 1000 J2 lines / plant were inoculated, and each plant was simultaneously watered with 20 mL of 3-hydroxy-2-methyl-4-pyranone solution at concentrations of 50 mg / L, 200 mg / L, 800 mg / L, and 1600 mg / L. The conventional control agent was Mat 500×, and the blank control was the same volume of sterile water. Each treatment consisted of 10 pots, and the experiment was repeated twice. The plants were cultivated in a smart greenhouse at a temperature of 22–28℃, a light intensity of 16 h / d, and a humidity of 60%–80%. Forty-two days after inoculation, the fresh weight of roots and the number of root oocytes per plant were investigated by covering the pots, and the inhibition rate per gram of oocytes was calculated, i.e., the control effect.

[0042] Number of root egg masses per gram = Number of root egg masses per plant / Fresh weight of roots per plant

[0043] Control efficacy (%) = (Number of root egg masses per gram in control - Number of root egg masses per gram in treatment) / Number of root egg masses per gram in control × 100

[0044] In a pot experiment using 1000 second-instar larvae per plant as an inoculation dose for the southern root-knot nematode, drenching the roots with 1.6 g / L of 2-hydroxy-3-methyl-2-cyclopenten-1-one showed a control efficacy of 36.68% against the southern root-knot nematode, significantly higher than that of the conventional plant-derived preparation 1.6 g / L matrine (20.62% efficacy, P<0.05). Meanwhile, this substance had no adverse effects on tomato plant growth.

[0045] Experiment 4:

[0046] Pot experiment on soybean cyst nematode inoculation dose of 1000 second-instar larvae / plant:

[0047] The method was the same as in Experiment 3, except that the southern root-knot nematode was replaced with soybean cyst nematode. 21 days after inoculation, the fresh weight of the roots and the number of cysts on the root surface were investigated by covering the pots, and the inhibition rate per gram of root cysts was calculated, which is the control effect.

[0048] Number of root cysts per gram = Number of root surface cysts per plant / Fresh weight of roots per plant

[0049] Control efficacy (%) = (Number of cysts per gram of root in control - Number of cysts per gram of root in treatment) / Number of cysts per gram of root in control × 100%

[0050] In a pot experiment using 1000 second-instar larvae per soybean cyst nematode inoculation dose, 1.6 g / L of 2-hydroxy-3-methyl-2-cyclopenten-1-one applied to the roots showed a control efficacy of 66.09% against soybean cyst nematodes, significantly higher than that of the conventional plant-derived preparation 1.6 g / L matrine (21.43% efficacy, P<0.05). Simultaneously, this substance had no adverse effects on soybean plant growth.

Claims

The application of 1,2-hydroxy-3-methyl-2-cyclopenten-1-one in the control of plant parasitic nematodes, characterized in that... The 2-hydroxy-3-methyl-2-cyclopenten-1-one is used to control plant parasitic nematodes.

2. The application of 2-hydroxy-3-methyl-2-cyclopenten-1-one according to claim 1 in the control of plant parasitic nematodes, characterized in that... The 2-hydroxy-3-methyl-2-cyclopenten-1-one is used as a nematicide to kill plant parasitic nematodes.

3. The application of 2-hydroxy-3-methyl-2-cyclopenten-1-one according to claim 1 in the control of plant parasitic nematodes, characterized in that... The 2-hydroxy-3-methyl-2-cyclopenten-1-one is used to control plant parasitic nematode diseases.

4. The application of 2-hydroxy-3-methyl-2-cyclopenten-1-one according to claim 1 in the control of plant parasitic nematodes, characterized in that... The plant parasitic nematodes mentioned are the southern root-knot nematode and the soybean cyst nematode.

Images