CN104824007A - Spreading oil for controlling rice blast - Google Patents

Abstract

The invention relates to a film spreading oil agent for preventing and treating rice blast, which is characterized in that it consists of the following components in weight percent: 0.1% to 20% of prochloraz, 0.1% to 20% of orysastrobin, surface active 1% to 15% of the agent, 1% to 30% of the water surface diffusing agent, 0.1% to 5% of the stabilizer, and the solvent is added to 100%; the weight ratio of prochloraz to orysastrobin is 5 to 1:1 ~5. The film spreading oil prepared by the present invention made of prochloraz and orysastrobin can not only significantly improve the control effect, prolong the lasting effect, but also save labor, labor and water, significantly reduce the cost of pesticides, and greatly reduce the resistance of bacteria. The emergence of sex and the rate of development of drug resistance.

Description

A film spreading oil agent for preventing and treating rice blast

technical field

The invention relates to a film-spreading oil agent compounded with prochloraz and orysastrobin (Orysastrobin) as active ingredients, belongs to the field of pesticides, and is suitable for the control of rice blast by spraying by bottle shaking method, water surface film-spreading method and poisonous soil method .

Background technique

Rice blast is one of the important diseases of rice, which can cause a large reduction in yield, and in severe cases, the yield can be reduced by 40% to 50%, and even the grains cannot be harvested. Mainly damage leaves, stems and ears.

Prochloraz, chemical name: N-propyl-N-[2-(2,4,6-trichlorophenoxy)ethyl]imidazole-1-carboxamide, its structural formula is: Prochloraz is a high-efficiency broad-spectrum fungicide of imidazoles. It acts by inhibiting the biosynthesis of sterols, has multiple functions such as prevention, protection and treatment, and has excellent control effects on various diseases caused by Ascomycetes and Deuteromycetes. It has an excellent therapeutic and eradicating effect on rice blast, sheath blight, fruit leaf spot, anthracnose, scab, melon and bean rust, powdery mildew, turf and ornamental plants that are common in field crops.

Orysastrobin, the chemical name is (2E)-2-(methoxyimino)-2-{2-[(3E,5E,6E)-S-(methoxyimino)-4,6 -Dimethyl-2,8-dioxa-3,7-dioxanon-3,6-dien-1-yl]phenyl}-N-methylacetamide. Orysastrobin is a methoxyacrylate (strobilurin) fungicide developed by BASF in Germany. This type of compound has a unique mechanism of action, mainly inhibiting the germination of spores and the formation of appendages on the living environment of pathogenic bacteria, and hindering the invasion of rice. The mycelia of rice blast fungus and sheath blight fungus grow in the body, control the increase of diseased stems, and are effective and long-lasting for some strains that are resistant to other fungicides.

High-efficiency agents have been used in large quantities and frequently throughout the year, resulting in serious resistance to them from various pathogens, and are not suitable for single use. Conventional spraying methods have low efficiency, high labor intensity, and serious environmental residues, and it is difficult to meet the requirements of large-scale planting areas for the prevention and control of pests and diseases.

Film spreading oil, also known as water surface diffusing agent, is based on the special aquatic environment characteristics. In order to improve the efficiency of pesticide application and reduce labor intensity, a special "oil" is made by dissolving the original drug of hydrophobic pesticide in an organic solvent. The medicine does not need to add water or soil, and does not use any plant protection equipment. After the dot-like application of the medicine on the water surface, the medicine spreads rapidly in waves, and is quickly and evenly distributed throughout the field. With the help of intermolecular non-covalent bond associations, A drug film layer is formed on the surface and gathers at the base of the crop stem. With the help of the siphon effect of the base of the aquatic crop, it can directly and effectively prevent and control various diseases, insect pests and weeds of the aquatic crop 20-30 cm away from the water surface. At the same time, the medicament enters the duct through the phloem of the stem and is transported to various parts of the crops, which has a long-term protection effect on the crops, can reduce the frequency of medication, and reduce labor costs.

At present, the active ingredient prochloraz has public reports in the literature, such as emulsifiable concentrate, hot fog, seed coating suspension, water emulsion, microemulsion, soluble solution and wettable powder. It has not been reported yet. Secondly, orysastrobin, the active component, is often reported in the literature that the single agent and compound agent of granules are widely used in rice fields, but the film spreading oil compounded with prochloraz has not been reported at home and abroad.

Contents of the invention

The technical problem to be solved in the present invention is to provide a method for preventing and treating rice blast for the above-mentioned problems in the prior art, such as rapid development of single agent resistance, poor drug efficacy, low efficiency of using conventional dosage forms, high labor intensity, and serious environmental residues. film spreading oil.

The technical scheme adopted by the present invention to solve the above-mentioned technical problems is that a film spreading oil agent for preventing and treating rice blast is composed of the following components in weight percent: prochloraz 0.1% to 20%, oryzastrobin 0.1% ～20%, surfactant 1%～15%, water surface diffusing agent 1%～30%, stabilizer 0.1%～5%, solvent supplemented to 100%; the weight ratio of prochloraz to orysastrobin It is 5～1:1～5.

The surfactant is fatty alcohol polyoxyethylene ether, octylphenol polyoxyethylene ether, alkylaryl polyoxypropylene polyoxyethylene ether, alkylphenol polyoxyethylene ether, phenylethylphenol polyoxyethylene ether , at least one of calcium dodecylbenzenesulfonate.

The water surface diffusing agent is at least one of triethylhexyl phosphoric acid, methyl amyl alcohol, gull gum or fatty acid polyethylene glycol ester.

Described stabilizer is at least one in benzoic acid, sorbic acid or dehydroacetic acid;

Described solvent is at least one of enumerating below:

(1) Aromatic solvents: xylene, trimethylbenzene, o-dichlorobenzene, tetramethylbenzene, diethylbenzene, methylnaphthalene, diesel oil, gasoline and second-line oil;

(2) Vegetable oil solvents: soybean oil, cottonseed oil, palm oil, rapeseed oil, castor oil, corn oil, turpentine; esterified vegetable oil: methyl oleate, ethyl oleate and dimethyl carbonate;

(3) Other solvents: ether, acetophenone, n-octanol, isoamyl alcohol and terpineol.

The application methods of the film-spreading oil agent in the present invention are bottle shake method, water-surface film-spreading method and poisonous soil method, and the appropriate dosage is determined according to the occurrence of the control object, and the usual dosage is 1L-5L/hm ² .

The beneficial effects of the present invention are:

1. Low labor intensity and high industrial control efficiency. The film-spreading oil agent does not need to use equipment to apply pesticides, does not need to be mixed with water, and reduces labor intensity. On average, a single person can spray 80-100 acres per day, and the work efficiency is 8-10 times that of conventional spraying. At the same time, the compound of orysastrobin and prochloraz is specialized in the control of rice blast, with low resistance and high control effect.

2. Increase the inhibition of different sites of mycelia, delay resistance, and synergize. Due to the massive, single and frequent use of conventional pesticides, many pathogens have developed severe resistance to them. Prochloraz and oryzastrobin are fungicides with different mechanisms of action. The combination of oryzastrobin and prochloraz itself does not produce antagonism, but increases the inhibition of prochloraz on the growth of different targets of rice blast mycelium, and plays a role To delay resistance, expand the role of the target spectrum.

3. High safety and low cost per mu. Film spreading oil adopts low toxicity original medicine and solvent, which has low toxicity to natural enemies insects, human body and animal husbandry. There are few residues during use, less threat to the ecology, and high safety. Combining low-resistance pesticides with conventional pesticides can improve the control effect and reduce the cost per mu. At the same time, the medicament is applied by dripping method, which releases labor force, and the labor cost is very low.

4. Targeted drug administration, the prevention and treatment effect is remarkable. The film-spreading oil agent can directly reach the base of rice, and through phloem systemic targeted drug delivery, it can increase the concentration of liquid medicine at the base of rice and significantly improve the control effect.

In summary, the film-spreading oil made of prochloraz and orysastrobin can not only significantly improve the control effect and prolong the lasting effect, but also save labor, labor and water, significantly reduce the cost of pesticides, and greatly reduce the cost of pesticides. The emergence of bacterial resistance and the rate of drug resistance.

Detailed ways

The present invention will be described in further detail below in conjunction with specific embodiments.

The following experiments were conducted by the Guangxi Agricultural Resources Environment and Agricultural Products Quality and Safety University Laboratory.

1. Indoor toxicity test

After pre-testing to determine the effective inhibitory concentration range of each agent, prochloraz, orysastrobin and their mixed preparations were serially diluted to 5 concentrations according to the active ingredient content gradient, and sterile water was used as a control. Refer to the "Pesticide Indoor Bioassay Test Guidelines for Fungicides", and use the growth rate method to measure. Add different concentrations of chemicals into sterilized petri dishes, 1mL per dish, and then add 10mL of sterilized and melted PDA medium, mix well to make a plate , and then the expanded colonies were made into = 0.8cm bacterial discs, 1 disc per dish, and each treatment was repeated 4 times, placed in a 25 ° C incubator for cultivation, and the colony diameter was measured once every 24 hours. Calculate the net growth rate and relative inhibition rate, convert the mycelia growth inhibition rate into a probability value (y), convert the liquid concentration (μg/mL) into a logarithmic value (x), and obtain the toxicity regression equation ( y=a+bx), and the _EC50 of each agent was calculated from this. The formula for calculating the antibacterial rate is as follows:

Mycelial growth inhibition rate (%) = (control colony diameter - treated colony diameter) / control colony diameter × 100

According to the co-toxicity coefficient method (CTC) of Sun Yunpei's method to evaluate the synergistic effect of drug mixture, that is, CTC≤80 is an antagonistic effect, 80﹤CTC﹤120 is an additive effect, and CTC≥120 is a synergistic effect.

The test results are shown in Table 1:

Table 1 Analysis table of toxicity determination results of oryzastrobin and prochloraz composition to rice sheath blight

Test drug Proportion Regression equation (y=a+bx) correlation coefficient _EC50 (mg/L) co-toxicity coefficient Orysastrobin / y=2.1503+1.2981x 0.9902 9.86 / prochloraz / y=3.1725+1.6945x 0.9912 14.99 / Oryzastrobin: Prochloraz 5:1 y=3.5334+1.4438x 0.9945 8.16 138.8 Oryzastrobin: Prochloraz 4:1 y=3.1968+1.9806x 0.9939 7.14 158.1 Oryzastrobin: Prochloraz 2:1 y=3.7056+1.5427x 0.9952 6.85 169.4 Oryzastrobin: Prochloraz 1:1 y=3.5989+1.6763x 0.9902 7.35 156.8 Oryzastrobin: Prochloraz 1:2 y=3.4705+1.6638x 0.9989 7.56 151.4 Oryzastrobin: Prochloraz 1:3 y=3.7841+1.5326x 0.9924 8.06 155.7 Oryzastrobin: Prochloraz 1:4 y=3.3541+1.7922x 0.9977 8.09 149.3 Oryzastrobin: Prochloraz 1:5 y=3.6541+1.4628x 0.9948 8.36 125.5

It can be seen from Table 1 that the EC ₅₀ of prochloraz and oryzastrobin against rice sheath blight are 14.99 mg/L and 9.86 mg/L respectively, and the toxicity index of oryzastrobin is higher than that of prochloraz ; Mixing of oryzastrobin and prochloraz in the ratio of 5:1 to 1:5 shows obvious synergistic effect, and when the weight percentage of oryzastrobin and oryzastrobin is 1:2, The co-toxicity coefficient is 169.4, the highest co-toxicity coefficient.

2. Determination of preparation performance

According to the following table, prepare 10 film-expanding oil agent samples, respectively measure the antibacterial activity of film-forming stability, expansion performance and base residual agent, and the determination methods of each index are as follows:

Film-forming stability: Take 1ml of each drug, drop it into the water surface of the beaker, and observe its film-forming stability. If the drug is dispersed to the lower water surface within 24 hours, the film-forming stability is poor, and it is recorded as "poor". If there is no drug within 24 hours Disperse to the water surface of the lower layer, if part of the agent is dispersed to the water surface of the lower layer within 24-72 hours, the film-forming stability is good, which is recorded as "good". If no agent is dispersed to the water surface of the lower layer after 72 hours, the film-forming stability is good, which is recorded as "excellent".

Expansion performance: take 1ml of each medicine, drop it into the water surface, and measure its diffusion radius. If the diffusion radius is <0.5m, the diffusion performance is poor, which is recorded as "poor". If 0.5m<diffusion radius<2m, the diffusion performance is good. , recorded as "good", if the diffusion radius > 2m, the diffusion performance is good, recorded as "excellent".

Antibacterial activity of residual pesticides at the base: After application in the paddy field, the base of rice 0-3 cm above the water surface was cut off 2 days and 7 days respectively, and the rice blast pathogen was inoculated indoors, and the incidence was investigated 10 days after the inoculation.

3. Product preparation and application examples

The present invention is illustrated with the following examples and field tests, but does not limit the scope and control objects of the present invention.

Example 1: 20.1% prochloraz · oryzastrobin film developing oil

At normal temperature and pressure, put prochloraz, orysastrobin and solvent into a stirred reaction vessel, and at a stirring speed of 160-250 rpm, the solvent stirs and dissolves prochloraz and orysastrobin, Then add a surfactant, stir well for 15 to 30 minutes, and make it evenly mixed to obtain 20.1% prochloraz-oryresstrobin film-developing oil.

Following the same steps as in Example 1, the following examples can be prepared.

Example 2: 21% prochloraz · oryzastrobin film developing oil

Example 3: 20% prochloraz · oryzastrobin film developing oil

Example 4: 20% prochloraz · oryzastrobin film developing oil

Example 5: 19% prochloraz · oryzastrobin film developing oil

Example 6: 14% prochloraz · oryzastrobin film developing oil

Example 7: 23% prochloraz · oryzastrobin film developing oil

Example 8: 23% prochloraz · oryzastrobin film developing oil

Example 9: 23% prochloraz · oryzastrobin film developing oil

Example 10: 22% prochloraz · oryzastrobin film developing oil

Example 11: 20% prochloraz · oryzastrobin film developing oil

Example 12: 20.1% prochloraz · orysastrobin film developing oil

The prepared film-spreading oil agent for controlling rice blast is a uniform oily liquid in appearance; it has good low-temperature compatibility, and no crystals and suspended solids are precipitated after refrigerated for 14 days at –5°C; it has low volatility and can be tested by hanging filter paper. As a result, the volatilization rate is lower than 30 percent; it is safe to plants and has no phytotoxicity; the viscosity is less than 10 mPa·s; and the conductivity is in the range of 1×10 ⁻⁶ to 1×10 ⁻¹⁰ s/cm.

Field efficacy test

Field experiment of various formulations of prochloraz and orysastrobin compound film-spreading oil to control rice blast

Application location: In a rice field in the suburbs of Leizhou City, Guangdong

Method of use: Examples 3, 5, 7, 9, and 10 were sprayed with an ultra-low-capacity sprayer, and 45% prochloraz SC and 40% rice blastling EC were sprayed with a conventional Gongnong 16 sprayer.

Assuming that the area of each experimental plot is 40m ² of paddy area, repeat 4 times, and investigate the control effect 7 days and 14 days after the application. Take one point in the north and one in the middle direction, survey 20 clusters at each point, record the total number of plants and the number of diseased plants at all levels, and check the occurrence degree of rice blast. The test results are shown in Table 2:

Table 2 The control effect of various formulations on the control of rice blast field test

Field test results show that a spreading oil agent for the control of rice blast can effectively control rice blast, and the control effect is better than that of prochloraz and Daobunling single agents at approximately the same dosage of active ingredients. At the same time, the test showed that the film-spreading oil agent had better control effect on rice blast than the suspension concentrate and the emulsifiable concentrate; under the same amount of active ingredients, the film-spreading oil agent had better persistence than the suspension concentrate and the emulsifiable concentrate.

Claims (2)

1. prevent and treat the film-spreading oil solution of rice blast for one kind, it is characterized in that, be made up of the component of following weight percent content: Prochloraz 0.1% ~ 20%, orysastrobin 0.1% ~ 20%, surfactant 1% ~ 15%, water surface diffusant 1% ~ 30%, stabilizing agent 0.1% ~ 5%, solvent complements to 100%; Described Prochloraz and the weight ratio of orysastrobin are 5 ~ 1:1 ~ 5.

2. the film-spreading oil solution of control rice blast according to claim 1, it is characterized in that, described surfactant is at least one in fatty alcohol-polyoxyethylene ether, OPEO, alkylaryl polyoxyethylene polyoxypropylene ether, alkylphenol polyoxyethylene, phenethyl phenol polyethenoxy ether, calcium dodecyl benzene sulfonate;

Described water surface diffusant is at least one in triethyl group hexyl phosphoric acid, methyl anyl alcohol, guar gum or fatty acid polyethylene glycol ester;

Described stabilizing agent is at least one in benzoic acid, sorbic acid or dehydroactic acid;

Described solvent is following cited at least one:

(1) aromatic hydrocarbon solvent: dimethylbenzene, trimethylbenzene, o-dichlorohenzene, durene, diethylbenzene, methyl naphthalene, diesel oil, gasoline and two wires oil;

(2) vegetable oil solvent class: soybean oil, cottonseed oil, palm oil, rapeseed oil, castor oil, corn oil, turpentine oil; Esterified vegetable oil: methyl oleate, ethyl oleate and dimethyl carbonate;

(3) other kind solvents: ether, acetophenone, n-octyl alcohol, isoamyl alcohol and terpineol.