CN104686529A - Drug combination for preventing wheat scab and application thereof - Google Patents

Abstract

The invention relates to a medicament combination for preventing and treating wheat scab and its application. The medicament combination is compounded with tebuconazole and salicylamine, prepared into a water suspension, and used for preventing The occurrence and prevalence of wheat head blight; by using a combination of agents, compared with a single agent, it has a broad spectrum of sterilization and high efficiency, and can effectively reduce the cost of use and reduce the resistance of pathogens.

Description

Combination of agents for preventing and treating wheat scab and its application

technical field

The invention belongs to the technical field of pesticides, and relates to a medicament combination for preventing and treating wheat scab, and more particularly relates to preparing the medicament combination into a suspension for the prevention and treatment of wheat scab.

technical background

Wheat scab (Fusarium head blight) is an important disease affecting wheat production. The disease is mainly caused by pathogenic fungi such as Fusarium graminearum, which leads to wilted ears of wheat and seriously affects the yield of wheat. At the same time, during the infection process, the bacteria can produce mycotoxins such as deoxynivalenol (NOD), Trichothecenes and Zearelanone, which are harmful to humans and animals. , Pollution of grains seriously affects the use value of wheat.

The control of wheat head blight is mainly through the selection of resistant varieties and the control of chemical agents. However, in actual production and application, varieties resistant to wheat scab are extremely scarce. The only recognized varieties are Sumai 3 and Wangshuibai, and these two varieties have poor agronomic traits and are difficult to be accepted by growers. At present, in the breeding of varieties resistant to wheat head blight, most of them focus on the screening of new resistance sources and the hybridization and aggregation of Sumai 3 and other varieties, but it is still in the research stage and is far from practical application in production.

For the chemical control of wheat head blight, there are few agents to choose from, among which tebuconazole is one of the main agents used. However, after long-term large-scale use, it is easy to cause resistance of gibberella to tebuconazole. Developing the combination of tebuconazole and other agents with different mechanisms of action is one of the important measures to delay drug resistance. Among the known compound agents, tebuconazole is mostly compounded with some old agents such as carbendazim and thiram. Long-term use is likely to lead to multi-resistance of wheat scab. It is urgent to find new agents and tebuconazole Compounding is carried out to reduce the risk of multi-resistance.

Salicylamine is a broad-spectrum fungicide, which has a strong inhibitory effect on a variety of fungi including Fusarium, and has extremely low toxicity, which is suitable for the control of wheat head blight. At present, there is no relevant report on the compounding of tebuconazole and salicylamine for the control of wheat head blight.

Contents of the invention

In the invention, the tebuconazole and salicylamine are compounded and prepared into a water suspension to prevent the occurrence and prevalence of wheat scab.

Based on this purpose, the technical solution of the present invention is: a bactericidal composition, characterized in that the active ingredient of the bactericidal composition is a compound composition of tebuconazole and salicylamine, and the weight ratio of the two is 1:4 to 4:1.

Preferably, the weight ratio of the two is 1:1˜4:1; more preferably, the weight ratio of the two is 4:1.

Further, the present invention relates to an aqueous suspension, which is characterized in that it contains 5% to 60% of the above-mentioned bactericidal composition and auxiliary agents, and the auxiliary agents are 0.2% to 5% by weight of wetting agent and 2% to 10% of emulsifying and dispersing agent , 0.1% to 3% of thickener, 3% to 5% of antifreeze, 0.4% to 5% of defoamer, and make up 100% of the rest with water, and said % is weight percentage.

The wetting agent is a combination of one or more of sodium dodecylsulfate, sodium dodecylbenzenesulfonate and pull-off powder.

The emulsifying dispersant is one or more combinations of sodium methylene bis-naphthalene sulfonate, sodium lignin sulfonate, alkylphenol polyoxyethylene ether, polyarylphenol polyoxyethylene ether phosphate.

The thickener is one or a mixture of xanthan gum, sodium alginate, guar gum and sodium carboxymethylcellulose.

The antifreeze is ethylene glycol.

The defoamer is n-octanol.

Preferably, the amount of the bactericidal composition is 20-50%; more preferably, the amount of the bactericidal composition is 40%.

Unless otherwise specified, "%" in this specification is "percentage by weight".

Further, the present invention also relates to the use of the above-mentioned fungicidal composition or aqueous suspension for preventing and treating wheat head blight.

The preparation method of the water-suspending agent of the present application: Put the measured components into an emulsifying shearing machine in proportion; shear at a high speed for 30 minutes to obtain the product, and spray it for use after dilution.

The active ingredients used in the fungicidal composition or aqueous suspension of the present invention are low-toxic agents, which are safe to non-target organisms and the environment, harmless to humans and animals, are suitable for use on wheat, and can effectively prevent and treat the occurrence and treatment of wheat scab. Popularity. At the same time, using a mixed dosage form, compared with a single agent, has a broad spectrum of sterilization and high efficiency, and can effectively reduce the cost of use and reduce the resistance of bacteria.

Detailed ways

In order to make the object, technical solution and advantages of the present invention more clear, the present invention is illustrated with the following specific examples, but the present invention is not limited to these specific examples.

Preparation Example

Example 1:

Tebuconazole 8wt%; Salicylamine 32wt%; Sodium dodecylbenzene sulfonate 2wt%, Sodium methylene bis-naphthalene sulfonate 3wt%; Alkylphenol polyoxyethylene ether 1.5wt%; Xanthan gum 0.5 wt%; ethylene glycol 3%; n-octanol 3wt%; the balance is made up with water.

Example 2:

Tebuconazole 10wt%; Salicylamine 30wt%; Sodium dodecylbenzenesulfonate 2wt%, Sodium methylene bis-naphthalene sulfonate 3wt%; Alkylphenol polyoxyethylene ether 1.5wt%; Xanthan gum 0.5 wt%; ethylene glycol 3%; n-octanol 3wt%; the balance is made up with water.

Example 3:

Tebuconazole 13wt%; Salicylamine 27wt%; Sodium dodecylbenzene sulfonate 2wt%, Sodium methylene bis-naphthalene sulfonate 3wt%; Alkylphenol polyoxyethylene ether 1.5wt%; Xanthan gum 0.5 wt%; ethylene glycol 3%; n-octanol 3wt%; the balance is made up with water.

Example 4:

Tebuconazole 20wt%; Salicylamine 20wt%; Sodium dodecylbenzenesulfonate 2wt%, Sodium methylene bis-naphthalene sulfonate 3wt%; Alkylphenol polyoxyethylene ether 1.5wt%; Xanthan gum 0.5 wt%; ethylene glycol 3%; n-octanol 3wt%; the balance is made up with water.

Example 5:

Tebuconazole 27wt%; Salicylamine 13wt%; Sodium dodecylbenzenesulfonate 2wt%, Sodium methylene bis-naphthalene sulfonate 3wt%; Alkylphenol polyoxyethylene ether 1.5wt%; Xanthan gum 0.5 wt%; ethylene glycol 3%; n-octanol 3wt%; the balance is made up with water.

Embodiment 6:

Tebuconazole 30wt%; Salicylamine 10wt%; Sodium dodecylbenzene sulfonate 2wt%, Sodium methylene bis-naphthalene sulfonate 3wt%; Alkylphenol polyoxyethylene ether 1.5wt%; Xanthan gum 0.5 wt%; ethylene glycol 3%; n-octanol 3wt%; the balance is made up with water.

Embodiment 7:

Tebuconazole 32wt%; Salicylamine 8wt%; Sodium dodecylbenzene sulfonate 2wt%, Sodium methylene bis-naphthalene sulfonate 3wt%; Alkylphenol polyoxyethylene ether 1.5wt%; Xanthan gum 0.5 wt%; ethylene glycol 3%; n-octanol 3wt%; the balance is made up with water.

Embodiment 8:

Tebuconazole 8wt%; Salicylamine 2wt%; Sodium dodecylbenzenesulfonate 2wt%, Sodium methylene bis-naphthalene sulfonate 3wt%; Alkylphenol polyoxyethylene ether 1.5wt%; Xanthan gum 0.5 wt%; ethylene glycol 3%; n-octanol 3wt%; the balance is made up with water.

Embodiment 9:

Tebuconazole 16wt%; Salicylamine 4wt%; Sodium dodecylbenzene sulfonate 2wt%, Sodium methylene bis-naphthalene sulfonate 3wt%; Alkylphenol polyoxyethylene ether 1.5wt%; Xanthan gum 0.5 wt%; ethylene glycol 3%; n-octanol 3wt%; the balance is made up with water.

Example 10:

Tebuconazole 40wt%; Salicylamine 10wt%; Sodium dodecylbenzene sulfonate 2wt%, Sodium methylene bis-naphthalene sulfonate 3wt%; Alkylphenol polyoxyethylene ether 1.5wt%; Xanthan gum 0.5 wt%; ethylene glycol 3%; n-octanol 3wt%; the balance is made up with water.

Example 11:

Tebuconazole 48wt%; Salicylamine 12wt%; Sodium dodecylbenzene sulfonate 2wt%, Sodium methylene bis-naphthalene sulfonate 3wt%; Alkylphenol polyoxyethylene ether 1.5wt%; Xanthan gum 0.5 wt%; ethylene glycol 3%; n-octanol 3wt%; the balance is made up with water.

One, biological embodiment

1. Determination of indoor bactericidal activity

1.1 Drug toxicity determination

Referring to the indoor bioassay test guidelines for pesticides, the growth rate inhibition method was used to determine the inhibitory effect of the tested single agent on the mycelium growth of wheat head blight. Mix different concentrations of medicinal liquid with melted PDA medium to make a drug-containing medium plate with a corresponding concentration gradient. The PDA plate without medicinal liquid was used as a blank control, and each concentration was repeated 3 times.

Get the bacterium cake of wheat scab (diameter 4mm) with puncher, inoculate to the center of the PDA plate containing medicine of different concentrations. Place in a 27°C incubator and cultivate until the diameter of the blank control colony reaches 2/3 of the culture dish, measure the diameter of the colony with the cross method, and calculate the respective inhibition rates.

Change the growth inhibition rate into the inhibition probability value and use it as the ordinate, transform the drug mass concentration into a logarithm value as the abscissa, and perform the linear regression relationship between the probability value (y) and the mass concentration logarithm (x) according to the bacteriostatic rate , seek toxicity regression equation, calculate EC ₅₀ value and correlation coefficient r, etc.

1.2 Research on compounding effect of salicylamine and tebuconazole

Compounding salicylamine and tebuconazole: the two original drugs are prepared according to the active ingredients in 4:1, 3:1, 2:1, 1:1, 1:2, 1:3, 1: 4 7 proportioning ratios (mass ratios) in total. The above formulations were tested for toxicity according to the drug toxicity test method.

To evaluate the joint effect of the mixture, based on the EC ₅₀ value, the type of joint effect of the mixture was evaluated by calculating the co-toxicity coefficient of the mixture.

CTC≥120 is a synergistic effect, 80≤CTC<120 is an additive effect, and CTC<80 is an antagonistic effect.

2. Test results

2.1 Drug toxicity test results

Table 1 Indoor toxicity test results of two kinds of pesticide technical substances against wheat head blight

It can be seen from Table 1 that the EC ₅₀ of tebuconazole against S. tritici is 2.9198 μg/mL; the EC ₅₀ of salicylamine against S. tritici is 21.1244 μg/mL.

Table 2 Indoor toxicity test results of tebuconazole and salicylamine compound against wheat head blight

It can be seen from Table 2 that all proportions of the compounded tebuconazole and salicylamine showed a certain synergistic effect, but the synergistic coefficients of different compounded proportions were different. Among them, when the compound ratio of tebuconazole and salicylamine was 4:1, the co-toxicity coefficient was the highest, which was 161.56.

2. Field experiment

1. Test method

Field spraying was carried out at the flowering stage of wheat, and each embodiment was diluted 3000 times for use, and the test was repeated 4 times for each treatment. 50% carbendazim WP diluted 1000 times was used as drug control, and clear water was used as blank control. Investigate the incidence of wheat head blight in wheat milk stage. 5 points on the diagonal of each plot were surveyed, and 100 plants were surveyed at each point. The disease condition of each panicle was counted according to the disease grading standard by graded counting method. At the same time, the effect of pesticide application on wheat growth was observed.

Grading method:

Level 0: no disease

Grade 1: less than 1/4 of the diseased spikelets.

Grade 2: Diseased spikelets account for 1/4 to 1/2 of the total.

Grade 3: Diseased spikelets account for 1/2 to 3/4 of the total.

Grade 4: Diseased spikelets account for more than 3/4 of the total.

Pharmacological Calculation Method

In the formula: CK—the condition index of the blank control area;

PT—the condition index of the drug treatment area;

2. Test results

As can be seen from Table 3, different embodiments all have different degrees of control effects on wheat scab. Wherein, when the active ingredients of tebuconazole and salicylamine are 40wt%, when the ratio of the two is 4:1 (Example 7), the control effect on wheat head blight is the best, which is higher than other ratios (Example 7). 1, embodiment 2, embodiment 3, embodiment 4, embodiment 5 and embodiment 6 and contrast agent treatment), and have no obvious impact on wheat growth. When active ingredient content was lower than 40wt% (embodiment 8 and embodiment 9), the control effect to wheat head blight obviously declined; when active ingredient content was higher than 40wt% (embodiment 10 and embodiment 11), to There was no significant change in the control effect of wheat head blight. It can be seen that when the active ingredients of tebuconazole and salicylamine are 40wt%, and the ratio of the two is 4:1, it is the best content and ratio of active ingredients, and it has a good control effect on wheat head blight .

Table 3 Field Effects of Different Embodiments Handling Control of Wheat Scab

A method of the present invention for controlling wheat scab has been described through specific examples. Those skilled in the art can learn from the content of the present invention to appropriately change links such as raw materials and process conditions to achieve other corresponding goals, and the relevant changes do not depart from the content of the present invention. All similar replacements and changes are considered by those skilled in the art Obviously, all are considered to be included within the scope of the present invention.

Claims (9)

1. A bactericidal composition, characterized in that the active ingredient of the bactericidal composition is a compound composition of tebuconazole and salicylamine, and the weight ratio of the two is 1:4 to 4:1. 2. The fungicidal composition according to claim 1, characterized in that the weight ratio of the two is 1:1 to 4:1. 3. bactericidal composition according to claim 1, is characterized in that, the weight ratio of the two is 4:1. 4. A water suspension, characterized in that the water suspension comprises 5% to 60% of the bactericidal composition and auxiliary agent described in any one of claims 1 to 3, and the auxiliary agent is a wetting agent 0.2 ～5wt%, 2%～10% of emulsifying dispersant, 0.1%～3% of thickener, 3%～5% of antifreeze, 0.4%～5% of antifoaming agent, the rest make up 100% with water, the stated % is weight percentage. 5. water suspension according to claim 4, is characterized in that, described wetting agent is one or more in sodium lauryl sulfate, sodium dodecylbenzenesulfonate and pull apart powder Combination; the emulsifying dispersant is one or more combinations of sodium methylene bis-naphthalene sulfonate, sodium lignin sulfonate, alkylphenol polyoxyethylene ether, polyarylphenol polyoxyethylene ether phosphate ; The thickener is one or a mixture of xanthan gum, sodium alginate, guar gum and sodium carboxymethyl cellulose; the antifreeze is ethylene glycol; the defoamer is positive octanol. 6. The aqueous suspension according to claim 4, characterized in that the amount of the bactericidal composition is 20-50%. 7. The aqueous suspension according to claim 4, characterized in that the consumption of the bactericidal composition is 40%. 8. The use of the fungicidal composition according to any one of claims 1 to 3 for preventing and treating wheat head blight. 9. Use of the water suspension concentrate according to any one of claims 4 to 7 for preventing and treating wheat head blight.