CN116616286B - Pesticide composition for preventing and treating banded sclerotial blight of wheat - Google Patents

Abstract

The present invention belongs to the technical field of pesticides, and specifically relates to a pesticide composition for preventing and treating wheat sheath blight. A pesticide composition for preventing and treating wheat sheath blight, wherein the active ingredient is a binary compound of magnolol and epoxiconazole, tebuconazole or fluopicolide. In the pesticide composition of the present invention, magnolol has a good synergistic effect after being compounded with epoxiconazole, tebuconazole or fluopicolide, which can improve the prevention and treatment effect of wheat sheath blight, reduce the dosage of pesticide application, reduce the prevention and treatment cost, and reduce the pesticide residue in agricultural products.

Description

A pesticide composition for preventing and controlling wheat sheath blight

Technical Field

The invention belongs to the technical field of pesticides, and particularly relates to a pesticide composition for preventing and treating wheat sheath blight.

Background technique

Wheat sheath blight is a worldwide disease. Wheat can be affected at all growth stages, causing symptoms such as rotten buds, dead seedlings, rotten flower stalks, lodging, and dry ears. In the wheat production process, Rhizoctonia cerealis and Rizoctonia solani can infect wheat and cause wheat sheath blight. The occurrence process of wheat sheath blight in the field in winter wheat areas is divided into the following five stages: pre-winter disease period, winter dormancy period, disease recovery period, disease peak period, and disease stability period. Among them, the disease period before winter mainly infects the leaf sheaths near the ground, forming white ears; during the overwintering dormant period, the pathogen overwinters with the wheat seedlings; the disease recovery period is mainly from the end of tillering to jointing, when the disease severity is not high; the peak disease period is mainly from the late jointing to the heading stage. After heading, the stalks become hard and the disease is basically stable. Sclerotia are produced on the diseased plants and fall into the soil. Severely diseased plants die due to lack of water, and dry ears and dry white ears appear in the field, seriously affecting wheat yield and wheat grain quality.

In wheat production, wheat field sheath blight is mainly controlled by chemical agents, such as triadimefon, diniconazole, thiophanate-methyl, tebuconazole, epoxiconazole and carbendazim. Then, with the unscientific abuse of chemical agents, the pathogens of wheat sheath blight have developed different degrees of resistance, making the control effect of wheat sheath blight unsatisfactory. Blindly increasing the dosage of chemical agents can improve the control effect in a short period of time, but it will aggravate the development of resistance, increase pesticide residues in agricultural products and increase environmental pressure.

Magnolia officinalis, CAS: 528-43-8, molecular formula: C ₁₈ H ₁₈ O ₂ , structural formula is as follows:

The patent with application number CN202110454042.2 discloses the use of magnolol as an agricultural fungicide, and specifically discloses that magnolol can effectively inhibit the growth of mycelium of pathogens such as sclerotinia disease, sheath blight, gray mold, fusarium head blight, anthracnose, seedling blight, vine blight, wilt and yellow dwarf disease.

Compounding different fungicidal active ingredients is one of the effective and convenient ways to develop new agents and prevent and treat drug-resistant diseases. The inventors found through indoor experiments that when magnolol is compounded with fluopiconazole, tebuconazole or fluopiconamide, it has a synergistic effect on wheat sheath blight pathogens within a certain mass ratio range, and can improve the control effect on wheat sheath blight. At present, there are no reports on the compounding of magnolol with fluopiconazole, tebuconazole or fluopiconamide.

The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

Summary of the invention

The purpose of the present invention is to provide a pesticide composition for preventing and treating wheat sheath blight, so as to solve the problems caused by unscientific abuse of chemical agents.

To achieve the above object, the present invention provides the following technical solutions:

A pesticide composition for preventing and treating wheat sheath blight, wherein the active ingredients are a binary combination of magnolol and epoxiconazole, tebuconazole or pentoconazole.

More specifically, the mass ratio of magnolol to epoxiconazole is 1-10:10-1.

More specifically, the mass ratio of magnolol to tebuconazole is 1-40:8-1.

More specifically, the mass ratio of magnolol to tebuconazole is 1-6:9-1.

Compared with the prior art, the present invention has the following beneficial effects:

The magnolol in the pesticide composition of the present invention has a good synergistic effect after being compounded with epoxiconazole, tebuconazole or fluopicolide, which can improve the control effect of wheat sheath blight, reduce the pesticide application dosage, reduce the control cost and pesticide residues in agricultural products. At the same time, it can also reduce the risk of drug resistance when using a single active ingredient and extend the service life of the agent.

Detailed ways

The following is a clear and complete description of the technical solution of the patent of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by technicians in this field without creative work are within the scope of protection of the present invention.

Example : Indoor biological activity test of magnolol compound

1. Test strain: Rizoctonia solani, collected from infected wheat plants, isolated in the laboratory and preserved on PDA medium.

2. Test Drugs

98% magnolol technical, 97% fluopicolide technical, 96% tebuconazole technical, 98% fluopicolide technical, all of the above agents are commercially available.

The test agent was first dissolved in dimethyl sulfoxide and then diluted with 0.1% Tween-80 aqueous solution to prepare a single-dose stock solution. Multiple groups of proportions were set, and each single-dose stock solution and proportioned mixture were set with 5 mass concentration gradients according to the equal ratio method.

3. Test methods

The mycelium growth rate method was used. 9 mL of pre-melted PDA medium was added to a sterile conical flask, and 1 mL of the drug solution was quantitatively drawn from low concentration to high concentration, respectively, and added to the above conical flasks. After being fully shaken, it was poured into a culture dish with a diameter of 9 cm to make a drug-containing plate of the corresponding concentration; and a treatment without drug was set as a blank control, and 10 replicates were set for each treatment. A 5 mm diameter puncher was used to cut the bacterial cake at the edge of the test strain colony, inoculated in the center of the drug-containing plate and the blank control plate, covered with a dish cover, and placed in a 25°C constant temperature box for 4 days. The colony diameter was measured by the cross method, and the inhibition rate of mycelium growth by different treatments was calculated.

4. Data analysis: DPS software was used for data statistical analysis. Linear regression was performed with the logarithmic value of fungicide concentration as x and the corresponding probability value of mycelium growth inhibition rate as y to obtain the toxicity regression equation and the toxicity _EC50 value of the agent against the target pathogen. The co-toxicity coefficient (CTC) was calculated according to the Sun Yunpei method.

5. Measurement results

The synergistic effect of the drug was evaluated based on the calculated co-toxicity coefficient (CTC), CTC ≤ 80 for antagonistic effect, 80 < CTC < 120 for additive effect, and CTC ≥ 120 for synergistic effect. The results are shown in Table 1-3.

Table 1 Indoor biological activity of magnolol and epoxiconazole against Rhizoctonia solani

Drug name and ratio EC50(mg/L) ATI TTI CTC Magnolia 9.2614 100.0000 -- -- Epoxiconazole 1.3948 663.9948 -- -- Magnolia nobile 1: Fluoxepiconazole 10 1.2079 766.7357 612.7226 125.1359 Magnolia phenol 1: Fluoxepiconazole 5 0.3663 2528.3647 569.9957 443.5761 Magnolia phenol 1: Fluoxepiconazole 3 1.3805 670.8729 522.9961 128.2749 Magnolia nobile 1: Fluoxepiconazole 1 1.9777 468.2914 381.9974 122.5902 Magnolol 3: Fluoxepiconazole 1 2.6013 356.0297 240.9987 147.7309 Magnolia phenol 5: Fluoxepiconazole 1 3.3998 272.4101 193.9991 140.4182 Magnolia nobile 10: Fluoxepiconazole 1 4.6031 201.1992 151.2723 133.0047

As shown in Table 1, after the active ingredients magnolol and epoxiconazole were compounded, the co-toxicity coefficient against Rhizoctonia solani was greater than 120 within the mass ratio range of 1-10:10-1, showing a synergistic effect.

Table 2 Indoor biological activity of magnolol and tebuconazole against Rhizoctonia solani

As shown in Table 2, after the active ingredients magnolol and tebuconazole were compounded, the co-toxicity coefficients against Rhizoctonia solani were all greater than 120 in the mass ratio range of 1-40:8-1, showing a synergistic effect.

Table 3 Indoor biological activity of magnolol and fluopicolide against Rhizoctonia solani

Drug name and ratio EC50(mg/L) ATI TTI CTC Magnolia 9.2614 100.0000 -- -- Fluoxathiapiprolin 0.8455 1095.3755 -- -- Magnolia nobile 1: Fluoxathiapiprolin 9 0.6482 1428.7874 995.8380 143.4759 Magnolia nobile 1: Fluoxathiapiprolin 6 0.7879 1175.4537 953.1790 123.3193 Magnolia nobile 1: Fluoxathiapiprolin 3 0.5172 1790.6806 846.5316 211.5314 Magnolia nobile 1: Fluoxathiapiprolin 1 1.1589 799.1544 597.6878 133.7077 Magnolia phenol 3: fluopicolide 1 2.0293 456.3840 348.8439 130.8276 Magnolia nobile 6: Fluoxathiapiprolin 1 0.9618 962.9237 242.1965 397.5795

As shown in Table 3, after the active ingredients magnolol and fluopicolide were compounded, the co-toxicity coefficients against Rhizoctonia solani were all greater than 120 in the mass ratio range of 1-6:9-1, showing a synergistic effect.

In summary, magnolol has a good synergistic effect when combined with fluopicolide, tebuconazole or fluopicolide, which can improve the prevention and control effect of wheat stripe blight. Based on this, the dosage of pesticide application can be reduced, the cost of prevention and control can be reduced, and the pesticide residues in agricultural products can be reduced.

The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims (1)

1. A pesticide composition for preventing and treating wheat sheath blight, characterized in that the active ingredient is a binary compound of magnolol and epoxiconazole, tebuconazole or fluopicolide; The mass ratio of magnolol to epoxiconazole is 1-10:10-1; The mass ratio of magnolol to tebuconazole is 1-40:8-1; The mass ratio of magnolol to fluopicolide is 1-6:9-1.