Bactericidal composition for preventing and treating fungal diseases of plants and application of bactericidal composition

Abstract

The invention discloses a bactericidal composition for preventing and treating plant fungal diseases and application. According to the invention, the iminoctadine tris-octyl alkyl benzene sulfonate is compounded with sclareol, tetramycin or fluxapyroxad, so that white powder and gibberellic disease caused by multi-drug resistance Blummeria graminis and Fusarium graminearum can be effectively prevented and controlled, a good prevention and control effect is achieved, multiple prevention by one spray is realized, the dosage of chemical agents is reduced, the prevention and control efficiency is improved, and the purpose of increasing the yield and income of wheat is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of pesticides, and in particular relates to a bactericidal composition for preventing and controlling plant fungal diseases and its application. Background Art

[0002] China is the world's largest wheat producer, with an annual planting area of ​​about 23 million hm2. 2 , with an annual output of about 120 million tons, accounting for 16.5% of the world's total wheat production.

[0003] Blumeria graminis Blumeria grassinis f. sp. wheat It belongs to the wheat-specific type of Brucella graminearum of the Poaceae family. The fungus spreads to the leaves of susceptible wheat through air currents through conidia. Wheat powdery mildew is common under suitable temperature and humidity conditions. In 1981, wheat powdery mildew was prevalent in China. The affected wheat fields generally reduced production by 5% to 10%, and severely diseased fields reduced production by more than 30%. At present, chemical control is the main method for preventing and controlling wheat powdery mildew in production. However, many places at home and abroad have reported that 97% of wheat powdery mildew strains in major wheat-growing areas in my country have developed resistance to triazole agents such as triadimefon, and the average resistance level to triadimefon is 34.92 times. The emergence of resistance has led to a significant reduction in the control effect of various agents on powdery mildew. In order to effectively control the damage of powdery mildew, it is urgent to develop high-efficiency and low-toxic fungicides or synergistic combinations.

[0004] Fusarium graminearum Fusarium gramineae Schwabe is one of the most important diseases in wheat production. The affected area of ​​wheat head blight in my country is about 7 million hm2 per year. 2 . Fusarium head blight fungi also secrete and produce deoxynivalenol (DON) toxins, which seriously affect the health of humans and animals. At present, my country's wheat-growing areas mainly spray benzimidazole fungicides such as carbendazim to control wheat head blight. However, wheat head blight has developed resistance to benzimidazole fungicides such as carbendazim, and the range of drug-resistant groups has a tendency to expand. Therefore, it is necessary to screen fungicides with different mechanisms of action to provide more efficient fungicides or synergistic combinations for the prevention and control of wheat head blight, so as to improve the prevention effect and delay drug resistance. Summary of the invention

[0005] The purpose of the present invention is to provide a fungicide composition for preventing and controlling plant fungal diseases and its application.

[0006] In order to achieve the purpose of the present invention, in the first aspect, the present invention provides a fungicidal composition for preventing and controlling plant fungal diseases, wherein the active components are: Biguanide trioctylbenzene sulfonate and sclareol; or,

[0007] Biguanide trioctylbenzene sulfonate and tetramycin; or,

[0008] Biguanide trioctylbenzene sulfonate and trifloxystrobin.

[0009] Furthermore, in the active component, the mass ratio of biguanide trioctylbenzene sulfonate to sclareol is (1-8):(1-6), preferably (1-6):(1-2), and more preferably 1:2, 1:1, 2:1, 4:1 or 6:1.

[0010] Furthermore, in the active component, the mass ratio of biguanide trioctylbenzene sulfonate to tetramycin is (50-100):1, preferably (70-90):1, more preferably 70:1, 80:1 or 90:1.

[0011] Furthermore, in the active component, the mass ratio of biguanide trioctylbenzene sulfonate to fluopyrabdo is (1-10):(1-10), preferably (1-5):(1-3), and more preferably 1:3, 1:1, 3:1 or 5:1.

[0012] In a second aspect, the present invention provides a pesticide preparation, which contains the fungicide composition, and the active component accounts for 5%-40% of the total mass of the pesticide preparation.

[0013] In a specific embodiment of the present invention, the dosage form of the pesticide preparation is a microemulsion, which is composed of the following components in parts by weight: 24 parts of 90% biguanide tri-octylbenzene sulfonate technical, 6 parts of 98% sclareol technical, 8 parts of dimethyl carbonate, 5 parts of propylene glycol, 3 parts of glycerol, 2 parts of PEG-400, 5 parts of fatty alcohol polyoxyethylene ether, 3 parts of Cremophor EL-35, 4 parts of chitosan and 3 parts of glycerol, and deionized water is supplemented to 100 parts.

[0014] In another specific embodiment of the present invention, the dosage form of the pesticide preparation is a microemulsion, which is composed of the following components in parts by weight: 8 parts of 90% biguanide trioctylbenzene sulfonate original drug, 0.1 parts of 15% tetramycin mother drug, 5 parts of acetone, 5 parts of dimethyl carbonate, 5 parts of fatty alcohol polyoxyethylene ether, 5 parts of polyoxyethylene fatty alcohol ether, 5 parts of ethylene glycol and 3 parts of glycerol, and deionized water is supplemented to 100 parts.

[0015] In another specific embodiment of the present invention, the dosage form of the pesticide preparation is a microemulsion, which is composed of the following components in parts by weight: 24 parts of 90% biguanide tri-octylbenzene sulfonate technical, 8 parts of 95% fluopicolide technical, 5 parts of tetrahydrofurfuryl alcohol, 10 parts of xylene, 5 parts of fatty alcohol polyoxyethylene ether, 5 parts of agricultural milk 600#, 3 parts of ethylene glycol, 2 parts of propylene glycol, and deionized water is supplemented to 100 parts.

[0016] In a third aspect, the present invention provides use of the fungicidal composition or the pesticide formulation in preventing and controlling plant fungal diseases (such as powdery mildew and fusarium head blight).

[0017] Pathogens that cause plant fungal diseases include but are not limited to Blumeria grassinis , Fusarium grasses , and those resistant to triadimefon, tebuconazole, and carbendazim Blumeria grassinis and Fusarium grasses .

[0018] The plants include, but are not limited to, cereal crops, such as wheat.

[0019] Furthermore, the application amount of the composition or the pesticide preparation is 40-50 ml / mu, the application interval is 7-10 days, and the number of applications is 2-3 times.

[0020] By means of the above technical solution, the present invention has at least the following advantages and beneficial effects: The present invention compounds biguanide trioctylbenzene sulfonate with sclareol, tetramycin or fluopyram, which can effectively prevent and control multidrug resistance. Blumeria grassinis and Fusarium gramineae It has good prevention and control effects on powdery mildew and ergot caused by wheat, realizes multiple preventions with one spray, reduces the use of chemical agents, improves prevention and control efficiency, and achieves the goal of increasing wheat production and income. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is the operation process of the combined toxicity detection of the agents against wheat powdery mildew in the preferred embodiment of the present invention.

[0022] Figure 2 This is an example of the toxicity test results of single doses and compound combinations of drugs in the preferred embodiment of the present invention. DETAILED DESCRIPTION

[0023] The present invention provides a composite synergistic fungicidal composition for preventing and controlling important fungal diseases of wheat. According to the indoor combined toxicity test, the fungicidal composition of the present invention has a Blumeria grassinis , Fusarium gramineae At the same time, according to the field efficacy test, the fungicide composition of the present invention has good prevention effect on powdery mildew and scab, realizes multiple prevention with one spray, reduces the number of pesticide applications, effectively reduces the amount of chemical agents used, improves the prevention and control efficiency, and achieves the goal of reducing the use of chemical pesticides and increasing their efficacy.

[0024] Biguanide tri-octylbenzene sulfonate is a new type of biguanide fungicide. Biguanide tri-octylbenzene sulfonate is a contact and preventive fungicide that mainly inhibits spore germination, germ tube elongation, attachment spores and hyphae formation, and acts on the biosynthesis of fungal ester compounds and cell membrane function. Biguanide tri-octylbenzene sulfonate is widely used to prevent and control fungal diseases caused by most ascomycetes and imperfect fungi, such as gray mold, powdery mildew, sclerotinia, vine blight, anthracnose, leaf spot and fruit soft rot of fruits and vegetables and various crops.

[0025] Sclareol is a natural product with important biological activity. Since sclareol has strong antibacterial activity and has a regulatory effect on fungal growth and plant growth, it can also be used in the field of pesticides. Sclareol has significant antibacterial activity against a variety of plant pathogens, and has an inhibitory effect on the growth and spore germination of rust fungi, thereby protecting plants from infection by these pathogens. As a natural product, low-concentration sclareol solutions cannot produce a good prevention and control effect on plant diseases. Therefore, it is necessary to combine chemical fungicides to expand the application level of the plant-derived active substance sclareol and achieve the purpose of delaying chemical fungicide resistance.

[0026] Tetramycin is a broad-spectrum, highly effective and low-toxic agricultural antibiotic fungicide. Tetramycin can not only effectively prevent and treat diseases caused by ascomycetes, basidiomycetes and imperfect fungi, but also induce the increase of the activity of defense enzymes such as phenylalanine ammonia lyase, peroxidase and polyphenol oxidase in the host, thereby improving the resistance of host plants to pathogens. This agent is used to prevent and treat rice damping-off, wheat powdery mildew and fusarium head blight, and poplar canker. It also has good antibacterial activity against vegetable sclerotinia, tomato leaf mold and pepper phytophthora.

[0027] Fluopyrab is a carboxamide fungicide with good preventive and therapeutic activity. It is a succinate dehydrogenase inhibitor, acting on succinate dehydrogenase in complex II of the mitochondrial respiratory chain, inhibiting the germination of pathogenic fungi and the growth of germ tubes and mycelium. Fluopyrab is effective in preventing and controlling major diseases of various crops, such as diseases caused by Septoria, Botrytis cinerea, powdery mildew, Cercospora, Puccinia, Rhizoctonia, and Pyricularia on cereals, soybeans, fruit trees, and vegetables, gray mold, rust, and powdery mildew on leguminous plants, damping-off disease on cotton, and diseases caused by Alternaria alternata on sunflowers and oilseed rapeseed.

[0028] At present, there is no research on the combination of biguanide trioctylbenzene sulfonate with sclareol, tetramycin or fluopyram. Blumeria grassinis and Fusarium gramineae In order to control drug resistance, the present invention has carried out a method of mixing biguanide trioctylbenzene sulfonate with sclareol, tetramycin or fluopyram in different proportions. Blumeria grassinis and Fusarium gramineae Combined toxicity study.

[0029] After a large number of experiments and repeated studies, the present invention found that after the biguanide trioctylbenzene sulfonate is compounded with sclareol, tetramycin or fluopyram, it can not only Blumeria grassinis and Fusarium gramineae It has a toxicity enhancement effect, and at the same time, it also shows good prevention and control effects on wheat powdery mildew in the field and also has a good prevention and control effect on wheat scab, realizing one spray for multiple preventions, improving the prevention and control efficiency, and achieving the effect of reducing the use of chemical pesticides and increasing their effectiveness. To this end, the fungicide composition provided by the present invention includes biguanide tri-octylbenzene sulfonate as an active component, as well as sclareol, tetramycin or fluopyram.

[0030] In order to further improve the combined toxicity of the bactericidal composition, the present invention also studies the specific compounding method of the active components, which is as follows: In the active component, the mass ratio of the biguanide trioctylbenzene sulfonate to sclareol is (1-8): (1-6). By controlling the ratio of the two, the combined toxicity of the composition can be significantly improved while controlling the cost.

[0031] Further preferably, the mass ratio of biguanide trioctylbenzene sulfonate to sclareol is (1-6):(1-2), which can significantly improve the combined toxicity of the composition to wheat powdery mildew and fusarium head blight while controlling the cost.

[0032] In some specific embodiments, the mass ratio of the biguanide trioctylbenzene sulfonate to sclareol is 1:2, 1:1, 2:1, 4:1 and 6:1.

[0033] In the active component, the mass ratio of the biguanide trioctylbenzene sulfonate to tetramycin is (50-100): 1. By controlling the ratio between the two, the combined toxicity of the composition can be significantly improved while controlling the cost.

[0034] More preferably, the mass ratio of the biguanide trioctylbenzene sulfonate to tetramycin is (70-90): 1. While controlling the cost, the combined toxicity of the composition to wheat powdery mildew and fusarium head blight can be significantly improved.

[0035] In some specific embodiments, the mass ratio of the biguanide trioctylbenzene sulfonate to tetramycin is 70:1, 80:1 or 90:1.

[0036] In the active component, the mass ratio of the biguanide trioctylbenzene sulfonate to fluopyrabdo is (1-10):(1-10). By controlling the ratio between the two, the combined toxicity of the composition can be significantly improved while controlling the cost.

[0037] More preferably, the mass ratio of the biguanide trioctylbenzene sulfonate to fluopyrabdo is (1-5):(1-3). While controlling the cost, the combined toxicity of the composition to wheat powdery mildew and fusarium head blight can be significantly improved.

[0038] In some specific embodiments, the mass ratio of the biguanide trioctylbenzene sulfonate to fluopyrabdo is 1:3, 1:1, 3:1, and 5:1.

[0039] The present invention also provides a pesticide preparation, which contains the above-mentioned fungicide composition.

[0040] Specifically, the pesticide preparation is in the form of a microemulsion.

[0041] The pesticide preparation of the present invention maintains resistance to triadimefon and carbendazim. Blumeria grassinis and Fusarium gramineae It has good prevention and control effects on powdery mildew and ergot caused by pathogens, realizes multiple preventions with one spray, improves prevention and control efficiency, and achieves the goal of increasing wheat production and income.

[0042] The active component accounts for 5%-40% of the total mass of the pesticide preparation.

[0043] The dosage form of the pesticide preparation is a pesticide dosage form microemulsion commonly used in the art.

[0044] The present invention provides an application of the bactericidal composition or the pesticide preparation in the control and prevention of drug resistance of powdery mildew and fusarium head blight. Experiments show that the implementation of the bactericidal composition or the pesticide preparation of the present invention can significantly improve the field control effect, achieve one spray for multiple preventions, significantly reduce the amount of chemical agents used, and achieve the purpose of increasing wheat production and income.

[0045] Preferably, the crop is a cereal crop, especially wheat, where the prevention and control effect is more significant.

[0046] The present invention provides a method for applying the above-mentioned bactericidal composition or pesticide preparation. The method for applying the preparation is as follows: controlling the application amount of the preparation to be 40-50 ml / mu, the application interval to be 7-10 days, and the application times to be 2-3 times.

[0047] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention. Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art, and the raw materials used are all commercially available products.

[0048] In the following embodiments: The original drug of biguanide trioctylbenzene sulfonate, with an active ingredient concentration of 90%, was purchased from the market.

[0049] The original drug of sclareol, with an active ingredient concentration of 98%, was purchased from the market.

[0050] Tetramycin stock drug, with an active component concentration of 15%, was purchased from the market.

[0051] Fluopyrab amide technical, with an active ingredient concentration of 95%, was purchased from the market.

[0052] Biguanide trioctylbenzene sulfonate wettable powder, with an active ingredient concentration of 40%, is commercially available.

[0053] Sclareol microemulsion, active ingredient concentration 10%. Preparation method is as follows: Step 1, 10 parts of sclareol, 30 parts of ethanol and 25 parts of fatty alcohol polyoxyethylene ether are mixed, stirred at 100r / min speed to dissolve, and then continued to stir for 40min; Step 2, 8 parts of sodium dodecyl sulfate are added to water, stirred to dissolve; under stirring conditions, the mixed solution of step 1 is slowly poured into the mixed solution of step 2, and deionized water is supplemented to 100 parts. After mixing, stirring is continued at 100r / min speed for 30min to obtain sclareol microemulsion. The parts are by mass.

[0054] The fluopicolide suspension concentrate, with an active ingredient concentration of 300 g / L, was purchased from the market.

[0055] Example 1 Combined toxicity of a mixture of biguanide trioctylbenzene sulfonate and sclareol, tetramycin or fluopicolide against wheat powdery mildew

[0056] Determination of wheat powdery mildew pathogens caused by the mixture of biguanide trioctylbenzene sulfonate with sclareol, tetramycin or fluopicolide using the detached leaf segment method Blumeria grassinis The combined toxicity.

[0057] Test pathogen strain: Blumeria graminis T BMX-1 strain, resistant to triadimefon and tebuconazole, is preserved by the Fungicide Research Laboratory, Institute of Plant Protection, Hebei Academy of Agricultural and Forestry Sciences. T For the BMX-1 strain, please refer to the sensitivity of wheat powdery mildew fungus to azoxystrobin and triadimefon, Zhang Yacan et al., Journal of Wheat Crops, 2015, 35(12): 1746-1750.

[0058] When the healthy indoor potted wheat seedlings grow to 1 leaf and 1 heart, the wheat powdery mildew spores are inoculated in excess using a sedimentation tower, and the spores are covered with glass covers for isolation and cultivation. 4 days after inoculation, infection points begin to appear on the wheat leaves. The first leaf of each plant is cut and cut into 3 cm leaf segments, which are placed in a culture dish with a diameter of 6 cm and about 20 ml of water agar medium containing 60ug / mL benzimidazole. Five leaf segments are placed in each dish. The leaf segments are placed face up on the bottom plate of the mist sedimentation tower to be sprayed with different agents and a series of concentrations of agents. The test drug was dissolved in acetone to prepare a mother solution with a concentration of 1000 μg / mL, and then biguanide trioctylbenzene sulfonate was mixed with sclareol, tetramycin or fluopyram in different mass ratios (1:6, 1:4, 1:2, 1:1, 2:1, 4:1, 6:1 and 8:1), (100:1, 90:1, 80:1, 70:1, 60:1 and 50:1) and (1:10, 1:5, 1:3, 1:1, 3:1, 5:1 and 10:1) to obtain mixed solutions with different ratios, which were then serially diluted with sterile water. Use air compressors to drive the nozzles to evenly spray the above-mentioned different agents and mixed series concentrations of the agents (QWJ-150 oil-free silent air compressor pressure 0.1 ~ 0.2mPa, sedimentation time 1 min), spray 1.5 mL of the solution per dish, 4 dishes for each concentration, repeat 4 times, and set up a blank control. After the drug-coated leaf segments are dried, cover the culture dishes. Place them in an incubator with L 16 h: D 8 h and culture them in vitro at 18 ± 1℃. After 7 days of culture, investigate the number of infection points in each leaf segment. Calculate EC using DPS software 50 and correlation coefficient.

[0059] Calculation of inhibition rate: Inhibition rate = (1-average number of infection points per leaf segment of treatment / average number of infection points per leaf segment of control) × 100%.

[0060] Refer to the Wadley formula to calculate the synergistic coefficient after mixing the drugs: EC 50 (th) = (a+b) / (a / EC 50 (A)+b / EC 50 (B)

[0061] SR=EC 50 (th) / EC 50 (ob)

[0062] In the above formula, a and b represent the proportion of the two fungicides in the mixture; EC 50 (A) and EC 50 (B) represent the actual observed EC of A and B respectively 50 Value, EC 50 (th) represents the expected theoretical EC after the mixture of two fungicides A and B in the ratio of a:b50 Value, EC 50 (ob) is the actual observed EC after the two fungicides A and B are mixed in the ratio of a:b 50 SR>1.5, synergistic effect; SR<0.5, antagonistic effect; SR between 0.5 and 1.5 indicates additive effect.

[0063] The experimental results are shown in Table 1~Table 3: Table 1 The combined toxicity of biguanide trioctylbenzene sulfonate and sclareol to wheat powdery mildew pathogens

[0064] As shown in Table 1, the mixture of biguanide tri-octylbenzene sulfonate and sclareol showed good inhibitory effect on the growth of wheat powdery mildew pathogens, and the synergistic coefficients of each ratio (1-8): (1-6) were all greater than 1.5, showing a synergistic effect, but the degree of synergism was different. Among them, when the ratio of biguanide tri-octylbenzene sulfonate to sclareol was 4:1, the synergistic effect was the most obvious, and the synergistic coefficient was 3.34.

[0065] The combined toxicity of biguanide trioctylbenzene sulfonate and tetramycin against wheat powdery mildew pathogen

[0066] As shown in Table 2, the mixture of biguanide tri-octylbenzene sulfonate and tetramycin showed a good inhibitory effect on the growth of wheat powdery mildew pathogens, and the synergistic coefficients of each ratio (50-100):1 were all greater than 1.5, showing a synergistic effect, but the degree of synergism was different. Among them, when the ratio of biguanide tri-octylbenzene sulfonate to tetramycin was 80:1, the synergistic effect was the most obvious, and the synergistic coefficient was 2.69.

[0067] Table 3 The combined toxicity of tri-octylbenzene sulfonate and tripyraclostrobin against wheat powdery mildew pathogens

[0068] As shown in Table 3, the mixture of tri-octylbenzene sulfonate and flupyracopyram showed a good inhibitory effect on the growth of wheat powdery mildew pathogens, and the synergistic coefficients of each ratio (1-10): (1-10) were all greater than 1.5, showing a synergistic effect, but the degree of synergism was different. Among them, when the ratio of tri-octylbenzene sulfonate and flupyracopyram was 3:1, the synergistic effect was the most obvious, and the synergistic coefficient was 3.40.

[0069] The operation process of the combined toxicity test of the pesticides against wheat powdery mildew is shown in Figure 1 .

[0070] Example 2 Combined toxicity of a mixture of biguanide trioctylbenzene sulfonate and sclareol, tetramycin or fluopyram against Gibberella tritici

[0071] Determination of the pathogenic fungus causing wheat fusarium rust by the mycelial growth rate method in the mixture of biguanide trioctylbenzene sulfonate and sclareol, tetramycin or fluopyram Fusarium gramineae The combined toxicity.

[0072] The pathogenic bacteria strains used for testing: Gibberella graminearum (strain ZF504, resistant to carbendazim), provided by Professor Zhou Mingguo of Nanjing Agricultural University. The strain ZF504 can be found in Study on the resistance of Fusarium graminearum to carbendazim, Wang Jianxin (supervisor: Zhou Mingguo), Nanjing Agricultural University, Master's thesis in 2000.

[0073] The test strain was pre-cultured using PDA medium. The PDA medium contained 200 g of potato, 20 g of glucose, 10 g of agar, and 1000 mL of distilled water. The original drug was dissolved in acetone to prepare a mother solution with a concentration of 10,000 μg / mL, and then the biguanide trioctylbenzene sulfonate was mixed with sclareol, tetramycin or fluopyram in different mass ratios (1:6, 1:4, 1:2, 1:1, 2:1, 4:1, 6:1 and 8:1), (100:1, 90:1, 80:1, 70:1, 60:1 and 50:1) and (1:10, 1:5, 1:3, 1:1, 3:1, 5:1 and 10:1) to obtain mixed solutions with different ratios. Then, the mixture was serially diluted with sterile water, mixed with the culture medium in a volume ratio of 1:9, and a series of drug-containing PDA plates were prepared, and a blank control was set at the same time. A 5 mm diameter bacterial cake was made on the edge of the pre-cultured strain and placed face down in the center of the drug-containing plate. The plate was cultured at 25°C. When the control colony expanded to about 80% of the culture dish, the diameter of each treatment and the control was measured using the cross method. EC was calculated using DPS software. 50 and correlation coefficient.

[0074] Calculation of inhibition rate: Inhibition rate (%) = [(control colony growth - treatment colony growth) / control colony growth] × 100%

[0075] Refer to the Wadley formula to calculate the synergistic coefficient after mixing the drugs: EC 50 (th) = (a+b) / (a / EC 50 (A)+b / EC 50 (B)

[0076] SR=EC 50 (th) / EC 50 (ob)

[0077] In the above formula, a and b represent the proportion of the two fungicides in the mixture; EC 50 (A) and EC 50 (B) represent the actual observed EC of A and B respectively 50 Value, EC 50 (th) represents the expected theoretical EC after the mixture of two fungicides A and B in the ratio of a:b 50 Value, EC 50 (ob) is the actual observed EC after the two fungicides A and B are mixed in the ratio of a:b 50 SR>1.5, synergistic effect; SR<0.5, antagonistic effect; SR between 0.5 and 1.5 indicates additive effect.

[0078] The experimental results are shown in Table 4~Table 6: Table 4 The combined toxicity of tri-octylbenzene sulfonate and claryol to the pathogen of wheat fusarium rust

[0079] As shown in Table 4, the mixture of biguanide tri-octylbenzene sulfonate and sclareol showed good inhibitory effect on the mycelial growth of wheat fusarium rust. The synergistic coefficients of each ratio (1-8): (1-6) were all greater than 1.5, showing a synergistic effect, but the degree of synergism was different. Among them, when the ratio of biguanide tri-octylbenzene sulfonate to sclareol was 4:1, the synergistic effect was most obvious, with a synergistic coefficient of 3.04. The synergistic effect of the mixture of biguanide tri-octylbenzene sulfonate and sclareol on wheat fusarium rust was different from that on wheat powdery mildew, and there were differences, but the synergistic ratio range was basically the same.

[0080] Table 5 The combined toxicity of tri-octylbenzene sulfonate and tetramycin against wheat fusarium head blight pathogens

[0081] As can be seen from Table 5, the mixture of tri-octylbenzene sulfonate and tetramycin showed good inhibitory effect on the mycelial growth of wheat fusarium, and the synergistic coefficient of each ratio (50-100): 1 was greater than 1.5, showing a toxicity synergistic effect, but the degree of synergism was different. Among them, when the ratio of tri-octylbenzene sulfonate and tetramycin was 80: 1, the synergistic coefficient was the largest, and the synergistic coefficient was 2.27. The synergistic effect of tri-octylbenzene sulfonate and tetramycin on wheat fusarium was different from the synergistic effect on wheat powdery mildew. There were differences, but the synergistic ratio range was basically the same.

[0082] Table 6 The combined toxicity of tri-octylbenzene sulfonate and tripyraclostrobin against the pathogen of wheat fusarium head blight

[0083] As shown in Table 6, the mixture of tri-octylbenzene sulfonate and flupyracoxad showed good inhibitory effect on the mycelial growth of wheat fusarium rust, and the synergistic coefficients of each ratio (1-10): (1-10) were all greater than 1.5, showing a synergistic effect, but the degree of synergy was different. Among them, when the ratio of tri-octylbenzene sulfonate to flupyracoxad was 3:1, the synergistic effect was most obvious, with a synergistic coefficient of 2.78. The synergistic effect of tri-octylbenzene sulfonate and flupyracoxad on wheat fusarium rust was different from that on wheat powdery mildew in terms of degree and trend, but the synergistic ratio range was basically the same.

[0084] See the examples of toxicity test results of single and compound drugs for Figure 2 Among them, the upper left is the toxicity test result of a single dose of biguanide tri-octylbenzene sulfonate, the upper right is the toxicity test result of a single dose of sclareol, and the bottom is the toxicity test result of the combination of biguanide tri-octylbenzene sulfonate and sclareol (4:1).

[0085] Example 3 Bactericidal composition microemulsion

[0086] (1) Preparation of 30% biguanide trioctylbenzene sulfonate·sclareol microemulsion (4:1)

[0087] 24% biguanide tri-octylbenzene sulfonate, 6% sclareol, 8% dimethyl carbonate, 5% propylene glycol, 3% glycerol, 2% PEG-400, 5% fatty alcohol polyoxyethylene ether, 3% Cremophor EL-35, 4% chitosan, and 3% glycerol were weighed and dissolved completely and mixed evenly, and deionized water was added to 100%, and a 30% biguanide tri-octylbenzene sulfonate·sclareol microemulsion was prepared after stirring.

[0088] (2) Preparation of 8.1% biguanide trioctylbenzene sulfonate·tetramycin microemulsion (80:1)

[0089] 8% biguanide tri-octylbenzene sulfonate, 0.1% tetramycin, 5% acetone, 5% dimethyl carbonate, 5% fatty alcohol polyoxyethylene ether, 5% polyoxyethylene fatty alcohol ether, 5% ethylene glycol, and 3% glycerol were weighed and dissolved completely and mixed evenly, and deionized water was added to 100%, and 8.1% biguanide tri-octylbenzene sulfonate·tetramycin microemulsion was prepared after stirring.

[0090] (3) Preparation of 32% biguanide trioctylbenzene sulfonate·flupyraclostrobin microemulsion (3:1)

[0091] 24% of tri-octylbenzene sulfonate of biguanide, 8% of fluopicolide, 5% of tetrahydrofurfuryl alcohol, 10% of xylene, 5% of fatty alcohol polyoxyethylene ether, 5% of Nongru 600#, 3% of ethylene glycol and 2% of propylene glycol were weighed and dissolved completely and mixed evenly, and deionized water was added to 100%, and a 32% tri-octylbenzene sulfonate of biguanide·fluopicolide microemulsion was prepared after stirring.

[0092] Example 4 Field efficacy of biguanide trioctylbenzene sulfonate and other agents and their combined preparations against wheat powdery mildew

[0093] The test was conducted in accordance with the "Guidelines for Field Efficacy Tests of Pesticides" GB / T17980.22-2000 "Guidelines for Efficacy Tests of Fungicides for Control of Powdery Mildew of Cereals" of the Institute for Drug Control of the Ministry of Agriculture and Rural Affairs.

[0094] The experimental field is located in Guantao County, Handan City, Hebei Province, and the wheat variety is Handan 6172. In the season when wheat powdery mildew often occurs, the first spray is carried out before the onset of powdery mildew, and the medicine is used twice in succession, with an interval of about 10 days between applications. The field disease situation is investigated 10 days after the last application of the medicine, and the disease index and control effect are calculated.

[0095] Table 7 Field test on control of wheat powdery mildew by biguanide trioctylbenzene sulfonate and other fungicides and their combination preparations

[0096] From the experimental results in Table 7, it can be seen that 30% biguanide tri-octylbenzene sulfonate·sclareol microemulsion, 8.1% biguanide tri-octylbenzene sulfonate·tetramycin microemulsion and 32% biguanide tri-octylbenzene sulfonate·flupyraclostrobin microemulsion showed good control effects on wheat powdery mildew at the test dose; compared with their single chemical agents, the dosage of chemical agents was significantly reduced, the relative effective dosage of chemical agents was reduced by more than 25%, and there was no adverse effect on crops and other beneficial organisms at the test dose.

[0097] The results also show that 30% biguanide tri-octylbenzene sulfonate·sclareol microemulsion, 8.1% biguanide tri-octylbenzene sulfonate·tetramycin microemulsion and 32% biguanide tri-octylbenzene sulfonate·fluoxadamide microemulsion can effectively control powdery mildew caused by powdery mildew fungi that are resistant to triadimefon and tebuconazole (preliminary research results show that the powdery mildew fungi at the test site have developed resistance to triadimefon and tebuconazole). The development of this formula is of great significance for controlling the drug resistance of powdery mildew fungi.

[0098] Example 5 Field efficacy of biguanide trioctylbenzene sulfonate with different fungicides and their combined preparations against wheat scab

[0099] The test was conducted in accordance with the "Guidelines for Field Efficacy Tests of Pesticides" NY / T 1464.15-2007 "Guidelines for Field Efficacy Tests of Fungicides for Controlling Wheat Fusarium Head Blight" of the Institute for Drug Control, Ministry of Agriculture and Rural Affairs.

[0100] The experimental field is located in Dingxing County, Baoding City, and the wheat variety is Shixin 737. The test was carried out in the season when wheat scab often occurs. The first spraying began at the flowering stage of wheat, and the drug was used twice in succession, with an interval of about 10 days. The field disease situation was investigated 10 days after the last application of the drug, and the disease index and control effect were calculated.

[0101] Table 8 Field test of biguanide trioctylbenzene sulfonate with different fungicides and their combined preparations against wheat fusarium head blight

[0102] From the experimental results in Table 8, it can be seen that 30% biguanide tri-octylbenzene sulfonate·sclareol microemulsion, 8.1% biguanide tri-octylbenzene sulfonate·tetramycin microemulsion and 32% biguanide tri-octylbenzene sulfonate·flupyraclostrobin microemulsion all showed good control effects on wheat fusarium rust at the test dose. Compared with their single chemical agents, the effective dosage of chemical agents was reduced by more than 25%, and there was no adverse effect on crops and other beneficial organisms at the test dose.

[0103] The results also show that 30% biguanide tri-octylbenzene sulfonate·sclareol microemulsion, 8.1% biguanide tri-octylbenzene sulfonate·tetramycin microemulsion and 32% biguanide tri-octylbenzene sulfonate·flupyraclostrobin microemulsion can effectively control fusarium scurf caused by fusarium scurf that is resistant to carbendazim (preliminary research results show that the fusarium scurf at the test site has become resistant to carbendazim). The development of this formula is also of great significance for controlling the drug resistance of fusarium scurf.

[0104] According to the above experimental results, 30% biguanide tri-octylbenzene sulfonate·sclareol microemulsion, 8.1% biguanide tri-octylbenzene sulfonate·tetramycin microemulsion and 32% biguanide tri-octylbenzene sulfonate·flupyraclostrobin microemulsion can simultaneously prevent and control wheat diseases such as powdery mildew and ergot, achieving multiple preventions with one spray, effectively reducing the use of chemical agents, improving prevention and control efficiency, and achieving the goal of increasing production and income.

[0105] Although the present invention has been described in detail above with general descriptions and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made based on the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims

1. A fungicidal composition for preventing and controlling plant fungal diseases, characterized in that: The active ingredients are: Biguanide trioctylbenzene sulfonate and sclareol; or, Biguanide trioctylbenzene sulfonate and tetramycin; or, Biguanide trioctylbenzene sulfonate and trifloxystrobin.

2. The bactericidal composition according to claim 1, characterized in that In the active component, the mass ratio of biguanide trioctylbenzene sulfonate to sclareol is (1-8):(1-6), preferably (1-6):(1-2), and more preferably 1:2, 1:1, 2:1, 4:1 or 6:

1.

3. The bactericidal composition according to claim 1, characterized in that In the active component, the mass ratio of biguanide trioctylbenzene sulfonate to tetramycin is (50-100):1, preferably (70-90):1, more preferably 70:1, 80:1 or 90:

1.

4. The bactericidal composition according to claim 1, characterized in that In the active component, the mass ratio of biguanide trioctylbenzene sulfonate to fluopyrabdo is (1-10):(1-10), preferably (1-5):(1-3), more preferably 1:3, 1:1, 3:1 or 5:

1.

5. A pesticide preparation, characterized in that: It contains the fungicide composition according to any one of claims 1 to 4, wherein the active component accounts for 5% to 40% of the total mass of the pesticide preparation.

6. The pesticide formulation according to claim 5, characterized in that: The pesticide preparation is in the form of a microemulsion, and is composed of the following components in parts by weight: 24 parts of 90% biguanide tri-octylbenzene sulfonate technical, 6 parts of 98% sclareol technical, 8 parts of dimethyl carbonate, 5 parts of propylene glycol, 3 parts of glycerol, 2 parts of PEG-400, 5 parts of fatty alcohol polyoxyethylene ether, 3 parts of Cremophor EL-35, 4 parts of chitosan and 3 parts of glycerol, and deionized water is supplemented to 100 parts.

7. The pesticide formulation according to claim 5, characterized in that The pesticide preparation is in the form of a microemulsion, and is composed of the following components in parts by weight: 8 parts of 90% biguanide trioctylbenzene sulfonate technical, 0.1 parts of 15% tetramycin parent drug, 5 parts of acetone, 5 parts of dimethyl carbonate, 5 parts of fatty alcohol polyoxyethylene ether, 5 parts of polyoxyethylene fatty alcohol ether, 5 parts of ethylene glycol and 3 parts of glycerol, and deionized water is supplemented to 100 parts.

8. The pesticide formulation according to claim 5, characterized in that: The pesticide preparation is in the form of a microemulsion, and is composed of the following components in parts by weight: 24 parts of 90% biguanide trioctylbenzene sulfonate technical, 8 parts of 95% fluopicolide technical, 5 parts of tetrahydrofurfuryl alcohol, 10 parts of xylene, 5 parts of fatty alcohol polyoxyethylene ether, 5 parts of agricultural milk 600#, 3 parts of ethylene glycol, 2 parts of propylene glycol, and deionized water to make up to 100 parts.

9. Use of the fungicidal composition according to any one of claims 1 to 4 or the pesticide preparation according to any one of claims 5 to 8 in preventing and controlling plant fungal diseases; Pathogens that cause fungal plant diseases include Blumeria graminis , Fusarium graminearum , and those resistant to triadimefon, tebuconazole, and carbendazim Blumeria graminis and Fusarium graminearum ; The plants include cereals, preferably wheat.

10. The use according to claim 9, characterized in that: The application amount of the composition or the pesticide preparation is 40-50 ml / mu, the application interval is 7-10 days, and the application times is 2-3 times.

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