Bactericide composition containing picoxystrobin and application thereof

Abstract

The invention discloses a bactericide composition containing picoxystrobin and application of the bactericide composition, and belongs to the technical field of pesticides. The active ingredients of the bactericide composition comprise picoxystrobin and mancozeb, and the weight ratio of picoxystrobin to mancozeb is (1: 80)-(1: 1). The invention finds that the effect of the mixture of picoxystrobin and mancozeb for preventing and treating the southern rust disease of corn is obviously higher than that of a single component, the synergistic effect of the mixture of picoxystrobin and mancozeb in the range of 1: 80 to 1: 1 is obvious, the optimal ratio is 1: 40, the composition has excellent prevention and treatment effect on the southern rust disease of corn, and the safety to crops and environment is improved.

Description

Technical Field

[0001] The invention relates to the technical field of pesticides, and in particular to a fungicide composition containing picoxystrobin and application thereof. Background Art

[0002] Southern corn rust is a fungal disease caused by Puccinia polysora. The disease is a typical airborne disease, characterized by rapid spread, strong outbreaks, and heavy damage and losses. It can occur in all above-ground tissues of corn plants, mainly damaging corn leaves, and in severe cases, it can also damage cobs, bracts, and even male flowers. Symptoms include small chlorotic spots on the leaves, which then develop into yellow-brown blisters and eventually form orange-yellow rust-like summer spores. These spore piles can seriously affect the photosynthesis of corn, causing the leaves to dry up, the plants to age prematurely, and even the entire plant to dry up, seriously affecting the yield and quality of corn.

[0003] Picoxystrobin is a methoxyacrylate fungicide, and its mechanism of action is a mitochondrial respiration inhibitor, that is, it inhibits mitochondrial respiration by electron transfer between cytochrome b and C1. It is effective in controlling strains that are resistant to 14-demethylase inhibitors, benzamides, tricarboxamides and benzimidazoles. Once picoxystrobin is absorbed by the leaves, it moves in the xylem and flows in the transport system with the water flow; it also flows in the gas phase on the surface of the leaves and flows in the xylem again after being absorbed from the gas phase into the leaves, and has a wide spectrum of fungicides. It is mainly used to control a variety of crop diseases, such as leaf blight, leaf rust, glumes blight, brown spot, powdery mildew, downy mildew, powdery mildew, etc.

[0004] Mancozeb is an organic sulfur protective fungicide and a low-toxic pesticide. Due to its wide range of fungicides and low resistance, its control effect is significantly better than other similar fungicides. Most of the compound fungicides in China are processed and prepared with mancozeb. Trace elements of manganese and zinc have obvious effects on promoting growth and increasing yield of crops, and are effective in preventing and treating pear scab, apple leaf spot, vegetable blight, downy mildew, and field crop rust. There is no relevant report in the prior art on the combined use of picoxystrobin and mancozeb to prevent and treat southern corn rust. Summary of the invention

[0005] In view of the above prior art, the purpose of the present invention is to provide a fungicide composition containing picoxystrobin and its application. The present invention combines picoxystrobin and mancozeb as a fungicide composition, which has a significant synergistic effect on the prevention and treatment of southern corn rust.

[0006] To achieve the above object, the present invention adopts the following technical solution:

[0007] A first aspect of the present invention provides a fungicide composition containing picoxystrobin, wherein the fungicide composition is compounded by picoxystrobin and mancozeb in a weight ratio of 1:80 to 1:1.

[0008] Preferably, the fungicide composition is prepared by compounding picoxystrobin and mancozeb in a weight ratio of 1:40.

[0009] The second aspect of the present invention provides the use of the above-mentioned fungicide composition in the following (1) or (2):

[0010] (1) Prevent and control southern corn rust;

[0011] (2) Prepare products for preventing and controlling southern corn rust.

[0012] Pesticides are the main means of dealing with plant diseases. The rational use of pesticides is the focus of research on the sustainable and effective prevention and control of crop diseases. Exploring the combination of pesticides is an innovative use and development trend of existing pesticides. The combination of different pesticides can achieve joint prevention and control of target diseases and improve prevention and control efficiency; it can also reduce the amount of pesticides used and reduce pesticide residues. However, after two or more pesticides are mixed, chemical reactions may occur between the agents, resulting in changes in the chemical properties of the active ingredients, making it impossible to achieve the purpose of compounding or causing pesticide damage. Therefore, how to effectively combine pesticides remains a difficult point.

[0013] Southern corn rust is a fungal disease that seriously affects corn yield and quality. Picoxystrobin and mancozeb are two existing fungicides and pesticides that have preventive and therapeutic effects on a variety of plant diseases, but there is no report on their use for the prevention and treatment of southern corn rust. The present invention uses picoxystrobin and mancozeb in combination, and unexpectedly finds that they have a significant synergistic effect on the prevention and treatment of southern corn rust, achieving a prevention and treatment effect of 1+1>2.

[0014] The third aspect of the present invention provides an agent for preventing and controlling southern corn rust, wherein the agent contains an effective amount of the above-mentioned fungicide composition.

[0015] Preferably, in the medicament, the weight percentage of the fungicide composition is 10-80%.

[0016] Furthermore, the medicament also contains pharmaceutical excipients; optional pharmaceutical excipients include but are not limited to: adhesives, emulsifiers, dispersants, wetting agents, stabilizers, etc.

[0017] Furthermore, the medicament can be prepared into various suitable pharmaceutical dosage forms, such as granules, powders, suspensions, aqueous solutions, aqueous emulsions, sustained-release preparations, tablets, and the like.

[0018] The fourth aspect of the present invention provides the use of the above-mentioned agent in the prevention and control of southern corn rust.

[0019] A fifth aspect of the present invention provides a method for preventing and controlling southern corn rust, comprising the following steps:

[0020] Before or in the early stages of southern corn rust, spray the above-mentioned agents on the above-ground parts of corn plants.

[0021] Beneficial effects of the present invention:

[0022] The present invention is the first to study and find that picoxystrobin and mancozeb have strong inhibitory activity on the spore germination of southern corn rust pathogen; the effect of a mixture of picoxystrobin and mancozeb for preventing and controlling southern corn rust is significantly higher than that of a single component, and the synergistic effect of the two is significant within the range of 1:80 to 1:1, with 1:40 being the best ratio, which can reduce the dosage of the agent, improve the prevention and control effect, reduce the cost of use, delay the resistance of the agent, and improve the safety to crops and the environment. DETAILED DESCRIPTION

[0023] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0024] As mentioned above, southern corn rust is a fungal disease that seriously affects corn yield and quality, and the combination of pesticides is the current trend in disease prevention and control research. However, since different pesticides may have complex action relationships after mixing, it is difficult to predict the effect of the compounded pesticides.

[0025] The present invention uses picoxystrobin and mancozeb in combination, and unexpectedly finds that, compared with single pesticides, the combined use of the two significantly improves the control effect on southern corn rust, thereby proposing the present invention.

[0026] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the technical solution of the present application will be described in detail below in conjunction with specific embodiments. If the specific experimental conditions are not specified in the embodiments, they are usually in accordance with conventional conditions or the conditions recommended by the reagent company; the reagents, consumables, etc. used in the following embodiments and comparative examples, unless otherwise specified, can be obtained through commercial channels. Among them:

[0027] The CAS number of picoxystrobin is 117428–22–5; the CAS number of mancozeb is 8018-01-7.

[0028] Example 1: Preparation of a fungicide composition containing picoxystrobin

[0029] Picoxystrobin and mancozeb are mixed in a weight ratio of 1:1 to serve as a fungicide composition for preventing and controlling southern rust of corn.

[0030] Example 2: Preparation of a fungicide composition containing picoxystrobin

[0031] Picoxystrobin and mancozeb are mixed in a weight ratio of 1:20 to serve as a fungicide composition for preventing and controlling southern corn rust.

[0032] Example 3: Preparation of a fungicide composition containing picoxystrobin

[0033] Picoxystrobin and mancozeb are mixed in a weight ratio of 1:40 to serve as a fungicide composition for preventing and controlling southern corn rust.

[0034] Example 4: Preparation of a fungicide composition containing picoxystrobin

[0035] Picoxystrobin and mancozeb are mixed in a weight ratio of 1:60 to serve as a fungicide composition for preventing and controlling southern rust of corn.

[0036] Example 5: Preparation of a fungicide composition containing picoxystrobin

[0037] Picoxystrobin and mancozeb are mixed in a weight ratio of 1:80 to serve as a fungicide composition for preventing and controlling southern rust of corn.

[0038] Example 6: Preparation of a fungicide composition containing picoxystrobin

[0039] Picoxystrobin and mancozeb are mixed at a weight ratio of 1:100 to serve as a fungicide composition for preventing and controlling southern corn rust.

[0040] Example 7: Preparation of a fungicide composition containing picoxystrobin

[0041] Picoxystrobin and mancozeb were mixed in a weight ratio of 20:1 to form a fungicide composition for preventing and controlling southern corn rust.

[0042] Application example: Indoor toxicity test of picoxystrobin and mancozeb mixture against southern corn rust pathogen

[0043] 1. Test pathogen: Southern corn rust (Puccinia polysora Underw).

[0044] 2. Test methods:

[0045] Refer to the spore germination concave slide method (NY / T 1156.1-2006) and the combined action determination of fungicide mixtures (NY / T 1156.6-2006) in the "Guidelines for Indoor Bioassay Tests of Pesticides" (NY / T 1156.1-2006). Use a pipette or a pipette to draw 1 mL from low concentration to high concentration and add them to small test tubes respectively, and then draw 1 mL of the prepared spore suspension to make the drug solution and spore suspension equal and mix evenly.

[0046] Use a micropipette to draw the above mixed solution and drop it onto a concave glass slide, then place it in a culture dish with a shallow layer of water, cover it to keep it moist, and culture it in an incubator at a suitable temperature. Repeat each treatment for no less than 4 times, and set a treatment without the drug as a blank control. Culture it in a light biochemical incubator at 28°C and a relative humidity of 90% for 5 hours.

[0047] When the spore germination rate of the blank control reaches more than 90%, check the spore germination of each treatment. Since the spore germination rate of southern corn rust is relatively low, the spore germination of each treatment is checked when the spore germination rate of the blank control reaches more than 85% during the test.

[0048] For each treatment, three or more fields of view were randomly observed in each replicate, and the total number of spores was not less than 200. The number of germination and the total number of spores were recorded respectively. The spore germ tube length was greater than the short radius of the spore and was considered to have germinated.

[0049] If the spore germination inhibition rate of the blank control is less than 5%, no correction is required; if the spore germination inhibition rate of the blank control is between 5% and 20%, the corrected inhibition rate of each treatment is calculated using the Abott formula; if the spore germination inhibition rate of the blank control is more than 20%, the test needs to be repeated.

[0050] According to the survey data, the relative inhibition rate of spore germination of each treatment was calculated in percentage (%). The control effect of each treatment concentration was calculated according to the formula, and then the DPS data processing software was used to calculate the test results. The toxicity regression equations and EC values ​​of the single agent and the mixtures with different ratios of the test agent were obtained. 50 and EC 90 The 95% confidence limit was calculated, and the co-toxicity coefficient (CTC) of the two drugs in different ratios was calculated to screen out the best ratio of the test drugs. The original data of all the repetitions of each treatment were recorded.

[0051] Corrected inhibition rate (%) = (spore germination rate of blank control - spore germination rate of treated) / spore germination rate of blank control × 100

[0052] The co-toxicity coefficient (CTC) of compound pharmaceutical mixtures is calculated according to Sun Yunpei's method. The formula for calculating the co-toxicity coefficient (CTC) is as follows:

[0053] Measured toxicity index (ATI) = (EC50 of standard agent / EC50 of test agent)50 )×100

[0054] Theoretical Toxicity Index (TTI) = Toxicity index of agent A × Percentage content of agent A in the mixture + Toxicity index of agent B × Percentage content of agent B in the mixture

[0055] Coefficient of Toxicity Combination (CTC) = (ATI / TTI)×100

[0056] According to the classification standard of the Coefficient of Toxicity Combination (CTC), CTC ≤ 80 indicates antagonistic effect, 80 < CTC < 120 indicates additive effect, and CTC ≥ 120 indicates synergistic effect.

[0057] 3. Test results:

[0058] The test results are shown in Table 1.

[0059] Table 1: Results of indoor combined toxicity determination of picoxystrobin and mancozeb against the pathogen of southern rust of maize

[0060]

[0061] It can be seen from the results in Table 1 that picoxystrobin and mancozeb have very high inhibitory activities against the spore germination of the pathogen of southern rust of maize, and the EC 50 are 0.0251 mg / L and 1.0246 mg / L respectively. When the ratio of the two is in the range of 1:80 to 1:1, the Coefficient of Toxicity Combination (CTC) is greater than 120, showing a significant synergistic effect and very high activity against the pathogen of southern rust of maize. Among them, the ratio of 1:40 is the best ratio.

[0062] In summary, the bactericidal composition of picoxystrobin and mancozeb compounded in the present invention has a significant synergistic effect, can reduce the dosage of the agent, improve the control effect on southern rust of maize, reduce the use cost, delay the drug resistance, and improve the safety for crops and the environment.

[0063] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A fungicide composition containing picoxystrobin, characterized in that: The bactericidal composition is prepared by compounding picoxystrobin and mancozeb in a weight ratio of 1:80 to 1:

1.

2. The fungicide composition according to claim 1, characterized in that The bactericidal composition is prepared by compounding picoxystrobin and mancozeb at a weight ratio of 1:

40.

3. Use of the fungicide composition according to claim 1 or 2 in the following (1) or (2): (1) Prevent and control southern corn rust; (2) Prepare products for preventing and controlling southern corn rust.

4. A medicament for preventing and treating southern corn rust, characterized in that: The medicament contains an effective amount of the fungicide composition according to claim 1 or 2.

5. Use of the agent according to claim 4 in the prevention and treatment of southern corn rust.

6. A method for preventing and controlling southern corn rust, characterized in that: The following steps are involved: Before or at the early stage of the onset of southern corn rust, the agent of claim 4 is sprayed on the aerial part of the corn plant.

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