CN106259436B - Formula and preparation method of bactericidal mixture for enhancing tebuconazole control effect - Google Patents

Abstract

The invention discloses a formula and preparation method of a bactericidal mixture for enhancing the prevention effect of tebuconazole, and relates to the application field of agricultural bactericides. The agricultural bactericidal mixture comprises two effective ingredients of tebuconazole and quicklime, and the mass fraction ratio of the two ingredients is 1:25-1:1200, and contains two effective ingredient agents or substances directly mixed before use, wherein tebuconazole is the original medicine or various preparations with tebuconazole as the main effective ingredient. The agricultural bactericidal mixture is mainly used for tree branch coating, trunk coating or winter and spring whitening, and can also be used for rainy season spraying, and can replace Bordeaux mixture or Bordeaux pulp to prevent and control branch and trunk diseases of fruit trees or prevent and control leaf diseases in rainy season. The invented agricultural bactericidal mixture overcomes the problems that Bordeaux mixture does not have systemic therapeutic effect, the preparation method is cumbersome, and the environmental pollution caused by a large amount of use, improves the prevention and control effect of tebuconazole, prolongs its lasting effect, reduces the dosage, and provides new ideas for the development and use of bactericides.

Description

A formulation and preparation method of a bactericidal mixture that enhances the preventive effect of tebuconazole

technical field

The invention belongs to the application field of agricultural fungicides, and relates to a formula and a preparation method of a fungicide mixture containing tebuconazole and quicklime.

Background technique

Tebuconazole is a triazole fungicide, which has highly effective systemic treatment, protection and eradication effects. It has a wide bactericidal spectrum and has good control effects on various crop diseases. In the prevention and control of fruit tree diseases, tebuconazole and other triazole fungicides are effective against brown spot, rust, powdery mildew, rot, branch and fruit ring disease, bagged fruit black spot, anthracnose of leaves and fruits. It has a good control effect on various diseases such as fruit tree disease, and has the advantages of broad spectrum, high efficiency, safety, and low toxicity. It is the first choice for the prevention and treatment of fruit tree diseases. However, tebuconazole has poor resistance to rain erosion, is easily decomposed by sunlight (ultraviolet decomposition), and has a short duration of effect. It is difficult to exert its effective control effect in the rainy season, thus limiting its application.

Bordeaux mixture is an important agent for preventing and controlling fruit tree diseases in the rainy season. It has the advantages of long-lasting effect and resistance to rain erosion. However, Bordeaux mixture has no systemic therapeutic effect, and the preparation method is cumbersome. It cannot be mixed with most insecticides and acaricides, and fruit farmers are reluctant to use it. Moreover, copper ions in Bordeaux mixture cannot be decomposed. It caused the increase of copper ions in the orchard environment and the deterioration of the ecological environment.

The traditional view also holds that chemical fungicides are unstable and easy to decompose under alkaline conditions, so organic fungicides and insecticides cannot be mixed with alkaline substances, otherwise it will accelerate the decomposition speed of the medicine, reduce the control effect of the medicine or even fail . Lime is alkaline, and few people mix lime with chemical fungicides in production practice and scientific experiments.

Lime has a good disinfection and sterilization effect. When lime meets water or humidity, it forms calcium hydroxide, which is strongly alkaline and has a strong killing effect on mold and bacteria. Lime is a disinfectant widely used in agricultural production, and is often used for soil disinfection; lime water is often used for seed and seedling treatment; after lime is sprayed on the surface of plants, calcium hydroxide can easily absorb carbon dioxide in the air to form calcium carbonate, forming white The film layer, which adheres to the surface of the plant, can withstand rain for a long time, and the white film layer can also resist ultraviolet rays and sunlight, and balance the temperature of the yin and yang sides of the tree.

Contents of the invention

Aiming at the defects of Bordeaux mixture and tebuconazole, the object of the present invention is to provide a set of formulation and preparation method of an agricultural bactericidal mixture of tebuconazole and quicklime, so as to overcome the lack of systemic treatment, cumbersome preparation method and large amount of Problems such as environmental pollution after use; prolong the duration of tebuconazole and improve its control effect; replace Bordeaux mixture or Bordeaux pulp to prevent and control fruit tree branch diseases or prevent leaf diseases during the rainy season. At the same time, it provides new ideas for the development and use of fungicides.

The technical principle of this invention is as follows: mixed spraying of tebuconazole and lime milk, the bactericidal effect of lime can be used at the initial stage of spraying to kill the germs on the surface of the plants or inhibit the growth of the germs, and protect the plants from the pathogenic bacteria. Infection; at the same time, after the tebuconazole in the mixed liquid is absorbed by the plant, it inhibits the growth and expansion of the infected bacteria, and exerts the systemic therapeutic effect of the drug. After mixed spraying of tebuconazole and lime, if the degradation speed is slow, the conversion of calcium hydroxide to calcium carbonate is fast, and tebuconazole will be mixed in the white film formed in the milk of lime, protected by the white film and protected from sunlight. Direct sunlight and photolysis prolong the duration of tebuconazole; after rainfall, tebuconazole can be released from the white film to exert its bactericidal effect and protect plants from the infection of pathogens.

Specific embodiments: the agricultural bactericidal mixture proposed by the present invention includes two kinds of main agent A and auxiliary agent B.

The active ingredient in main agent A is tebuconazole. The dosage form of the main agent A can be wettable powder, suspension concentrate, water dispersible granule, emulsifiable concentrate, etc., and its active ingredient content is not less than 5%. The corresponding other auxiliary agents are commonly used agricultural surfactants such as wetting agents, Dispersants and other auxiliaries, including mineral carriers, etc.

The molecular formula of tebuconazole is C ₁₆ H ₂₂ ClN ₃ O, the English common name is Tebuconazole, and the chemical name is (RS)-1-(4-chlorophenyl)-4,4-dimethyl-3-(1H-1 ,2,4 Triazol-1-ylmethyl)pentan-3-ol, the relative molecular mass is 307.8. Tebuconazole is a high-efficiency, broad-spectrum, systemic triazole fungicidal pesticide, which has three functions of protection, treatment and eradication, with a broad bactericidal spectrum and long-lasting effect. Tebuconazole exerts its bactericidal effect mainly by inhibiting the biosynthesis of ergosterol in fungi.

The auxiliary agent B is quicklime, which is quicklime block or quicklime powder.

The preferred mass/number ratio of agent A and agent B in the formula combination is 1:25-1:1200. When used as a spray, the usual concentration of agent A is 50mg/kg-200mg/kg (active ingredient), and the concentration of agent B is 5g/kg-20g/kg; when used for coating, the usual concentration of agent A is 250mg/kg -2000mg/kg, the concentration of agent B is 100g/kg-300g/kg.

Application Example 1: Experiment of Controlling Anthracnose Leaf Blight

Test agents include: 1) tebuconazole 43% suspension concentrate, produced by Jiangsu Jianpai Agrochemical Co., Ltd., diluted 3000 times for use; 2) Bordeaux mixture ratio is copper sulfate: quicklime: water = 1:2: 200; 3) The use concentration of quicklime is 1%, that is, weigh 50g of quicklime, add 50mL of water for digestion, add 1950ml of clear water, filter with four layers of gauze, and prepare milk of lime, then add 3000mL of water to make 1% lime water; 4 ) Weigh 1.7g tebuconazole 43% suspension concentrate, dilute it with 3000mL water, and mix it into 2000mL milk of lime to form a mixture of tebuconazole and lime.

The pathogenic bacteria used for inoculation was Leaf blight of apple anthracnose, which was collected from Jinshuai apple in Dangshan, Anhui in 2011. Before inoculation, transfer the preserved strains to PDA medium and activate at 25°C. When the colonies grow to 2/3 of the petri dish, scrape off the aerial hyphae with an inoculation loop, and continue to cultivate at 25°C for 2-3 days. When orange-yellow conidia horns grow on the cultured colony, pick the conidia horns, put in an appropriate amount of pure water, mix well, adjust the concentration of the spore suspension to ¹⁰⁴ /mL with a hemocytometer, and add a concentration of 0.1 % Tween-20, spare. The spore suspension is prepared now and placed for no more than 1 hour.

In 2014, in the Jiaozhou Science and Technology Demonstration Park of Qingdao Agricultural University, 10 "Gala" apple trees with good growth potential, numerous branches and healthy leaves were selected for 5 years. pesticides. During the test, the chemical liquid was evenly sprayed on the whole tree with a knapsack electric sprayer, and the spraying method of "two reverses and one buckle" was adopted when spraying the chemical, until the chemical liquid flowed down on the leaf surface, and clear water was used as a blank control. Two trees were treated with each chemical agent, and water was sprayed as a blank control.

On the 3rd day, 7th day, 14th day, 21st day and 28th day after the medicament treatment, cut 3 well-growing branches from the apple trees treated with each medicament respectively, and keep 3 healthy and uniform branches for each branch. Disease-free mature leaves were placed in an ice box and brought back to the laboratory for in vitro inoculation.

The treated branches were inserted into the tissue culture bottle for hydroponics, and the spore suspension was evenly sprayed onto the inoculated leaves with a hand-held sprayer until water droplets flowed down. Cover the inoculated shoots with plastic bags, transfer them to a 25°C light incubator for moisturizing cultivation, and untie the bag after 24 hours; continue to cultivate in the same incubator for 48 hours, when the number of diseased spots on the leaves of the blank control group no longer increases, Check and record the number of lesions on each inoculated leaf. The control effect of the pesticide was calculated according to the number of lesion spots on the leaves.

Control effect (%)=(average number of diseased spots on control leaves-average number of diseased spots on treated leaves)/(average number of diseased spots on control leaves)×100.

All the experiments were repeated twice at the end of May and July respectively, each time 3 shoots were inoculated with each agent, and a total of 9 leaves were inoculated.

Results: As shown in Table 1 (accompanying drawing 1), the experimental results of 10 repeated inoculations twice showed that the control effect of tebuconazole and quicklime mixture on anthracnose leaf blight was 71%, which was slightly higher than that of using tebuconazole alone The control effect of tebuconazole and quicklime was 58%, and the difference was not significant; from the 3rd day to the 28th day of inoculation after spraying, the control effect of tebuconazole and quicklime mixture on anthracnose leaf blight was higher than that of tebuconazole alone. Control effect, the control effect of the 21st day after spraying had the largest difference. The control effect of the mixture of tebuconazole and quicklime on anthracnose leaf blight was slightly lower than that of Bordeaux mixture (83%), and was basically the same as that of quicklime, and there was no significant difference among the three.

Conclusion: After mixed use of tebuconazole and quicklime, the control effect on anthracnose leaf blight is slightly improved, indicating that quicklime does not promote the degradation of tebuconazole, and tebuconazole can be mixed with quicklime.

Application example 2: Experiment on prevention and treatment of brown spot disease

The test set up 3 drug treatments and 1 water control: 1) 43% tebuconazole suspension 3000 times liquid. 43% Tebuconazole SC was produced by Jiangsu Jianpai Agrochemical Co., Ltd. 2) 43% tebuconazole suspension concentrate 3000 times liquid + 1% quicklime. Weigh 3.3g of 43% tebuconazole suspending agent and dilute with 9000mL of water; weigh 100g of quicklime, add 200mL of water for digestion, add 1000ml of clear water, filter with four layers of gauze, prepare lime milk, and directly mix it into 9000mL of lime milk, Mix well to form a mixture of tebuconazole and lime. 3) Bordeaux mixture with double amount of lime. The ratio of Bordeaux mixture is copper sulfate: quicklime: water = 1:2:200.

On June 25, 2014, in the Jiaozhou Science and Technology Demonstration Park of Qingdao Agricultural University, 20 Fuji apple trees with good growth potential and healthy leaves for 5 years were randomly selected, and 5 apple trees were treated with each chemical agent. Processed three times on 1st and 21st August. 5 long shoots in the east, west, north, south, and middle were marked on each tree, and a total of 100 shoots were marked, and the incidence base of brown spot was investigated before spraying. Spray with a knapsack electric sprayer, and spray the liquid medicine evenly on the whole tree until all the leaves flow down.

No other fungicides and insecticides were applied to the pesticide-applied trees, and the water and fertilizer management was carried out according to the normal orchard management plan, and the brown spot fungus was transmitted completely through natural transmission. In the later stage of apple growth, the investigation and records of the disease of the leaves on the marked apple branches were conducted twice on September 4 and October 9. The severity of disease on apple leaves was recorded according to the following grading method:

Grade 0: The leaves do not have any visible brown spot lesions, disease spots or conidia discs;

Grade 1: There are sporadic lesions on the leaves, and the area of lesions does not exceed 5% of the leaf area;

Grade 2: There are a small amount of diseased spots on the leaves, and the area of the diseased spots accounts for 6%-20% of the entire leaf area;

Grade 3: There are a large number of lesion spots on the leaves, and the lesion area accounts for 21%-40% of the entire leaf area, but the leaf surface does not turn yellow;

Grade 4: There are a large number of diseased spots on the leaf surface, and the area of the diseased spots accounts for more than 40% of the entire leaf area, or the leaves have turned yellow and will fall off soon;

Grade 5: The leaves have fallen off, leaving only leaf scars on the branches.

After the investigation, the disease index on each branch was calculated in units of branches, and then the average disease index of each chemical treatment was calculated based on the disease index on each branch, and variance analysis was performed to calculate the control effect.

Disease index=∑(leaf disease severity at the time of final investigation-leaf disease severity in June)/(total number of leaves on branches×5).

Control effect=100×(the disease index of the control branch-the disease index of the treated branch)/the disease index of the control branch.

Result: As shown in Table 2 (attached figure 2), after three times of medication in June, July and August of 2014, the results of the two surveys showed that the control effect of the mixture of tebuconazole and quicklime on brown spot was 80%. Above, slightly higher than the control effect of tebuconazole spraying alone, there is no significant difference between the two; the control effect of tebuconazole mixed with quicklime, and single use of tebuconazole is significantly higher than that of Bordeaux mixture.

Conclusion: After mixing tebuconazole with quicklime, the control effect of tebuconazole on brown spot disease is not reduced, but can be slightly improved; it shows that quicklime does not promote the degradation of tebuconazole, and tebuconazole can be mixed with quicklime.

The fungicide formulated according to the formula of the present invention can be used for tree body coating, drying or whitening in winter and spring, and can also be used for rainy season spraying. The sprayed agent has protective, therapeutic and eradicating activities, and can be used to prevent and control diseases caused by fungi such as Ascomycetes, Deuteromycetes and Basidiomycetes on various fruit trees or forests, such as apple trees, pear trees, peach trees, cherries, etc. Rot, ring spot, anthracnose, gummosis on the branches of fruit trees, anthracnose leaf blight, spot defoliation, etc. on the leaves.

The preparation of the agricultural bactericidal mixture according to the formula of the present invention has the following advantages: 1) the cost of raw materials is low, the source is wide, the preparation is easy, and the use is convenient; 2) within a certain proportion range, there is a synergistic effect, which improves the disease prevention effect; 3) After quicklime is used, the persistence period of tebuconazole can be extended; 4) the frequency of application is reduced, and the input of manpower, material resources and financial resources of fruit growers is reduced; 5) environmental safety is improved, and the pressure caused by chemical pesticides on the environment is alleviated.

Description of the drawings: Figure 1 shows the average number of lesions and control effects formed on each leaf of Gala apple leaves sprayed with different pesticides in Table 1 after being sampled at different times and inoculated with anthracnose leaf blight; Control effect of three consecutive application of pesticides on Fuji apple against apple brown spot.

Claims (1)

1. a kind of fungicide mixture of enhancing Tebuconazole preventive effect, it is characterised in that：Including two kinds of effective ingredients of Tebuconazole and quick lime, The quality parts ratio of two kinds of compositions is 1:25-1:1200, the medicament of effective ingredient is using preceding direct mixing containing there are two types of, can use In coating or spray pesticide；

The Tebuconazole refers to Original Tebuconazole, or with Tebuconazole be main effective ingredient wettable powder, suspending agent, water Dispersible granule, wherein the content of effective ingredient Tebuconazole is not less than 5% in each dosage form；

The quick lime is lime block, pulverized limestone or the white lime for adding water resolution within 48 hours；

The direct mixing refers to adding a small amount of water to be made into milk of lime after clearing up quick lime, filters off residue, is directly mixed in Tebuconazole In prepared liquid, used after being diluted to required concentration；Or mix Tebuconazole with pulverized limestone, being then watered directly makes With.