Bactericidal composition for preventing and controlling sunflower white rust and its application

Abstract

The invention discloses a fungicide composition for preventing and controlling sunflower white rust and its application. The active ingredients of the fungicide composition are composed of Bacillus amyloliquefaciens and Rhodomyces thulophilus. The two active ingredients in the fungicide composition have a significant synergistic effect, and have an excellent control effect on sunflower white rust caused by infection of sharp herb white rust fungus. In addition, the amount of the fungicide composition used is small, which can reduce the amount of chemical pesticides used and reduce pollution to the environment.

Description

Technical Field

[0001] The invention belongs to the technical field of pesticides, and particularly relates to a fungicide composition comprising Bacillus amyloliquefaciens and Rhodomyces thulophilus as effective ingredients, and application of the fungicide composition in preventing and controlling sunflower white rust. Background Art

[0002] White rust refers to a disease caused by white rust fungus, which mostly occurs in the Cruciferae family and can harm leaves, flower organs, etc. In the early stage of the disease, small yellow spots can be seen on the front of the leaves, which then gradually expand and turn yellowish, and white pus-like spots appear on the back of the leaves. In the later stage, the epidermis of the pus-like spots ruptures and white powder is released.

[0003] White rust disease has almost never occurred in Asteraceae sunflower before, but it has broken out on a large scale in recent years, with a field disease rate of about 30%, and in severe cases, the disease rate can reach more than 70%, which seriously affects the yield and quality of sunflower. Different from the common species of white rust pathogens in Cruciferae, the pathogen of sunflower white rust disease is Albugo aechmantherae Zhang et Y.X.Wang sp.nov.. Albugo aechmantherae is a kind of white rust fungus named by Zhang Zhongyi and Wang Yingxiang, belonging to the Acanthaceae on Yuelu Mountain, and is the pathogen of the fungal disease of the hairy herb of the genus Acanthaceae. The sunflower white rust disease rate caused by the infection of the sharp herb white rust disease is high, the onset time is early and the cycle is long, and the resistance to chemical agents is strong. There is no effective control agent registered for the production of sunflower white rust disease caused by this new pathogen in my country so far, and most of the conventional chemical agents have produced higher resistance or poor effect against the new pathogen, making the disease control effect poor. Summary of the invention

[0004] In view of this, it is necessary for the present invention to provide a fungicide composition for preventing and controlling sunflower white rust. The active ingredients of the fungicide composition are composed of Bacillus amyloliquefaciens and Rhodomycetes sulfidophilus. It has an excellent control effect on sunflower white rust caused by infection by white rust of sharp herbs, and the dosage is small, which can reduce the use of chemical pesticides and reduce environmental pollution.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] The invention firstly provides a fungicide composition for preventing and controlling sunflower white rust. The active ingredients of the fungicide composition consist of Bacillus amyloliquefaciens and Rhodomyces thiophilus.

[0007] In a further embodiment, in the fungicide composition, the gram ratio of Bacillus amyloliquefaciens to Rhodomyces sulfidophilus is (100) billion CFU / gram: (100) billion CFU / gram.

[0008] In a further embodiment, in the fungicidal composition, the gram ratio of Bacillus amyloliquefaciens to Rhodobacterium sulfidophilum is 4 billion CFU / gram:400 million CFU / gram.

[0009] In a further embodiment, the bactericidal composition further comprises an adjuvant, wherein the content of the active ingredient is (100) million CFU / gram.

[0010] According to a further embodiment, the active ingredient content is 4.4 billion CFU / gram.

[0011] In a further embodiment, the bactericidal composition is in the form of a liquid preparation.

[0012] In a further embodiment, the liquid preparation is an aqueous suspension.

[0013] In a further embodiment, the adjuvant is any acceptable adjuvant in pesticides;

[0014] Preferably, the auxiliary agent is selected from at least one of a dispersant, a wetting agent, a preservative and a solvent.

[0015] The present invention further discloses the use of the aforementioned fungicide composition in preventing and controlling sunflower white rust.

[0016] In a further embodiment, the sunflower white rust is caused by infection by Albugo serrata.

[0017] The beneficial effects of the present invention are as follows:

[0018] The active ingredients of the fungicide composition of the present invention are composed of Bacillus amyloliquefaciens and Rhodomycetes sulfidophilus. The two active ingredients are compounded to have a significant synergistic effect, and have an excellent control effect on sunflower white rust caused by infection of white rust fungus on sharp herbs. In addition, the amount of the fungicide composition used is small, which can reduce the amount of chemical pesticides used and reduce pollution to the environment. DETAILED DESCRIPTION

[0019] Embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0021] A first aspect of the present invention provides a fungicide composition for preventing and controlling sunflower white rust, wherein the active ingredients of the fungicide composition consist of Bacillus amyloliquefaciens and Rhodomyces thiophilus.

[0022] Bacillus amyloliquefaciens is a genus of Bacillus that can secrete active substances such as antimicrobial proteins, antibiotics, and enzyme-active polypeptides to promote crop growth and prevent and treat crop diseases. Currently, it is mainly used to control gray mold and bacterial diseases on crops such as sunflowers, and there is no report that it has a preventive effect on white rust.

[0023] Rhodovulum sulfidophilum is a microorganism of the genus Rhodovulum. It can enhance plant disease resistance by inducing plant systemic disease resistance and improving plant immunity. It can also secrete anti-target proteins and directly inactivate target activity. It is currently used to control plant nematodes and viruses. There are few studies on its effectiveness against fungal diseases, and there are no reports on white rust.

[0024] Bacillus amyloliquefaciens and Rhodomyces thiophilus are both natural microbial strains, and both have a certain preventive effect on bacterial diseases when used alone. In the face of the problem that there is currently no effective preventive agent registered for the production of sunflower white rust caused by the infection of sharp herb white rust fungus, conventional chemical agents have high resistance. The present invention innovatively compounded the two active ingredients, and found that the combination of the two had an obvious synergistic effect on sunflower white rust, providing a new idea for the prevention and control of sunflower white rust. In addition, the compounding mechanism of the two is relatively new and is not easy to produce resistance, which is of great significance to sunflower production and disease control.

[0025] In the present invention, in the bactericidal composition, the gram ratio of Bacillus amyloliquefaciens to Rhodomyces sulfidophilus is (100) billion CFU / g: (100) billion CFU / g. Preferably, in the bactericidal composition, the gram ratio of Bacillus amyloliquefaciens to Rhodomyces sulfidophilus is 4 billion CFU / g: 400 million CFU / g.

[0026] The bactericidal composition of the present invention also includes an adjuvant, which is any acceptable adjuvant in pesticide science. Specifically, the bactericidal composition of the present invention can be made into commonly used dosage forms in agriculture such as water-dispersible granules, water suspensions, emulsifiable concentrates, dispersible oil suspensions, seed treatment agents, wettable powders, suspoemulsions, emulsions in water, microcapsule suspensions, and microemulsions by certain technical means. As a further improvement of the present invention, the dosage form of the bactericidal composition described herein is preferably a liquid preparation, which has obvious advantages in absorption efficiency of active ingredients, safety, and ease of use, and has excellent storage, stability, and activity; more preferably, the liquid preparation adopts a water suspension.

[0027] Furthermore, the total amount of active ingredients (Bacillus amyloliquefaciens and Rhodomyces sulfidophilus) of the fungicidal composition provided herein can be selected according to specific factors to obtain the expected prevention and control effect. In some typical embodiments of the present invention, the content of the active ingredients in the fungicidal composition is (10-200) billion CFU / g; preferably, the content of the active ingredients is 4.4 billion CFU / g.

[0028] In addition, it can be understood that the adjuvants described in this article may optionally contain pesticide-acceptable adjuvants. Specific examples include but are not limited to at least one of a dispersant, a wetting agent, a preservative, and a solvent. The specific type can be selected based on conventional adjuvants in the art, so it will not be elaborated here.

[0029] The third aspect of the present invention provides the use of the fungicide composition according to the first aspect of the present invention in preventing and controlling sunflower white rust; the sunflower white rust is caused by infection by white rust of sharp herbs, and the combination of Bacillus amyloliquefaciens and Rhodomyces thiophilus as effective active ingredients has a significant control effect on the sunflower white rust caused by the specific pathogen. In addition, the fungicide composition described herein can also be used in other crops of the Cruciferae and Asteraceae families.

[0030] The present invention is described below by means of specific examples. It should be noted that the following specific examples are only for illustrative purposes and do not limit the scope of the present invention in any way. In addition, unless otherwise specified, methods without specific conditions or steps are conventional methods, and the reagents and materials used can be obtained from commercial channels.

[0031] Example 1

[0032] The bactericidal composition in this embodiment is an aqueous suspension, and its composition and dosage are as follows:

[0033]

[0034]

[0035] Example 2

[0036] The bactericidal composition in this embodiment is an aqueous suspension, and its composition and dosage are as follows:

[0037] Ingredient name content Bacillus amyloliquefaciens 8 billion CFU / g Rhodomyces thiophilus 200 million CFU / g Sodium lignin sulfonate 2.2％ Sodium Lauryl Sulfate 3.5％ Xanthan gum 0.57％ Sodium Benzoate 2.06％ Ethylene glycol 2.7％ water Top up to 100%

[0038] Example 3

[0039] The bactericidal composition in this embodiment is an aqueous suspension, and its composition and dosage are as follows:

[0040] Ingredient name content Bacillus amyloliquefaciens 4 billion CFU / g Rhodomyces thiophilus 400 million CFU / g Sodium lignin sulfonate 1.0％ Sodium Lauryl Sulfate 1.45％ Xanthan gum 0.06％ Sodium Benzoate 1.2％ Ethylene glycol 1.1％ water Top up to 100%

[0041] Example 4

[0042] The bactericidal composition in this embodiment is an aqueous suspension, and its composition and dosage are as follows:

[0043]

[0044]

[0045] Example 5

[0046] The bactericidal composition in this embodiment is an aqueous suspension, and its composition and dosage are as follows:

[0047] Ingredient name content Bacillus amyloliquefaciens 100 million CFU / g Rhodomyces thiophilus 1 billion CFU / g Sodium lignin sulfonate 5.0％ Sodium Lauryl Sulfate 6.3％ Xanthan gum 4.0％ Sodium Benzoate 2.1％ Ethylene glycol 3.8％ water Top up to 100%

[0048] Comparative Example 1

[0049] The bactericidal composition in this comparative example is an aqueous suspension, and its composition and dosage are as follows:

[0050] Ingredient name content Rhodomyces thiophilus 1.2 billion CFU / g Sodium lignin sulfonate 5.0％ Sodium Lauryl Sulfate 6.3％ Xanthan gum 4.0％ Sodium Benzoate 2.1％ Ethylene glycol 3.8％ water Top up to 100%

[0051] Comparative Example 2

[0052] The bactericidal composition in this comparative example is an aqueous suspension, and its composition and dosage are as follows:

[0053]

[0054]

[0055] Comparative Example 3

[0056] The bactericidal composition in this comparative example is an aqueous suspension, and its composition and dosage are as follows:

[0057] Ingredient name content Bacillus sub-tilis 100 million CFU / g Rhodomyces thiophilus 1 billion CFU / g Sodium lignin sulfonate 5.0％ Sodium Lauryl Sulfate 6.3％ Xanthan gum 4.0％ Sodium Benzoate 2.1％ Ethylene glycol 3.8％ water Top up to 100%

[0058] Test Example 1 Physical and Chemical Properties Test

[0059] Standards: GB / T 19136-2003 Pesticide thermal storage stability test method; GB / T 19137-2003 Pesticide low temperature stability test method; GB / T 28137-2011 Pesticide persistent foaming test method. Test results are shown in Table 1.

[0060] Table 1 Physical and chemical tests of aqueous suspensions of Examples 1-5

[0061]

[0062] It can be seen from the test results in Table 1 that the water suspension concentrates in Examples 1-5 are qualified in terms of suspension rate, hot storage and cold storage stability, long-lasting foaming ≤ 20 ml, spore activity germination rate exceeding 90%, and excellent physical and chemical properties. Stability, storage properties and activity are all very well guaranteed.

[0063] Test Example 2 Biological Activity Test

[0064] The test target is Albugo aechmantherae Zhang et Y.X.Wang sp.nov., and the test agents are Bacillus amyloliquefaciens, Rhodomyces thiophilus (and two mixed preparations with different contents, all from Anhui Fengle Agrochemical Co., Ltd.

[0065] The test method refers to the agricultural industry standard of the People's Republic of China "Guidelines for Indoor Bioassay Tests of Pesticides" bactericides NY / T 1156.1-2006, NY / T 1156.2-2006, NY / T 1156.6-2006, and the test adopts the method of inhibiting pathogenic fungal spores. DPS data processing software is used for statistical analysis to calculate the EC50, EC90, b value standard error and its 95% confidence limit of each agent to evaluate the activity of the test agent. The calculation formula involved is as follows:

[0066] ATI of the mixture:

[0067] In the above formula:

[0068] S---EC50 of standard bactericide, in μg / ml;

[0069] M---EC50 of the mixture, in μg / ml.

[0070] Theoretical toxicity index of mixture TTI: TTI = TIA × PA + TIB × PB;

[0071] In the above formula:

[0072] TIA---A toxicity index of drugs;

[0073] PA---the percentage of A agent in the mixture, in %;

[0074] TIB---Toxicity index of B agent;

[0075] PB---the percentage of B agent in the mixture, in %.

[0076] Co-toxicity coefficient (CTC value) of the mixture:

[0077] In the above formula:

[0078] ATI---Actual toxicity index of mixture;

[0079] TTI---theoretical toxicity index of mixture.

[0080] If the co-toxicity coefficient (CTC) of the mixture is ≥120, it shows a synergistic effect; CTC≤80 shows an antagonistic effect; 80<CTC<120 shows an additive effect.

[0081] The specific toxicity test results are shown in Table 2. (In Table 1, A:B refers to the gram ratio of Bacillus amyloliquefaciens and Rhodomyces sulfidophilus. For example, if A:B=100:1, the content of Bacillus amyloliquefaciens in the mixture is 10 billion CFU / g, and the content of Rhodomyces sulfidophilus is 100 million CFU / g. And so on.)

[0082] Table 2 The results of 7-day toxicity test of each single agent and its mixture against white rust of pointed herbs

[0083] Test drug Regression equation EC50(×mg / L) AT1 TTI CTC value Bacillus amyloliquefaciens (A) y=5.2367+1.9151x 0.7523 66.99 / Rhodomyces thiophilus (B) y=5.6050+2.0327x 0.5040 100.00 / A:B=100:1 y=5.6583+1.4525x 0.3522 143.10 67.32 212.57 A:B=80:2 y=5.8391+1.4020x 0.2520 200.00 67.80 294.99 A:B=40:4 y=6.2573+1.4646x 0.1385 363.90 70.00 519.89 A:B=20:8 y=5.9303+1.4657x 0.2319 217.34 76.42 284.38 A:B=1:10 y=5.7654+1.3883x 0.2810 179.36 97.00 184.91

[0084] The results of indoor toxicity determination in Table 2 show that the EC50 of Bacillus amyloliquefaciens and R. thulophilus against Albugo sphaerocephala are 0.7523 mg / L and 0.5040 mg / L, respectively. When the gram ratio of Bacillus amyloliquefaciens to R. thulophilus is 100:1 to 1:10 (i.e., the contents of Bacillus amyloliquefaciens and R. thulophilus are (100 to 100) billion CFU / g and (100 to 100) billion CFU / g, respectively, the co-toxicity coefficient (CTC) is greater than 120, indicating that each ratio has a synergistic effect, especially when the gram ratio of Bacillus amyloliquefaciens to R. thulophilus is 40:4 (i.e., the contents of Bacillus amyloliquefaciens and R. thulophilus are 400 million CFU / g and 400 million CFU / g, respectively), the co-toxicity coefficient (CTC) is the largest, and the synergistic effect is significant.

[0085] Test Example 3 Field efficacy test

[0086] Test location: Xiangshan District, Huaibei City; the test field area is 6 mu, the soil pH is 6.4, and the organic matter content is 2.4%.

[0087] Experimental crop: Sunflower, sown on May 2, 2022, and cultivated and managed in accordance with local scientific cultivation measures.

[0088] Test target: Albugo serrata.

[0089] Test agents: The water suspensions in Examples 1-5 and Comparative Examples 1-3, and the conventional chemical agent 30% trifloxystrobin tebuconazole suspension, were all produced and prepared by Anhui Fengle Agrochemical Co., Ltd.

[0090] Application method: conventional spraying.

[0091] Application time: July 20, 2022, at the beginning of the disease.

[0092] Efficacy investigation: Two investigations were conducted, 3 days and 10 days after application, to investigate the disease condition of the leaves.

[0093] Investigation method: visual inspection, investigate the affected area, calculate the incidence rate and prevention and control effect.

[0094] The disease index and control effect calculation formulas are as follows:

[0095] Disease index = [Σ(number of diseased leaves (flowers) at each level × corresponding disease level value) / total number of leaves surveyed × highest level representative value] × 100;

[0096] Control effect = [(control disease index - treatment disease index) / control disease index] × 100%.

[0097] The dosage and efficacy of the experimental agents are shown in Table 3.

[0098] Table 3 Field efficacy test dosage and control effect

[0099]

[0100] It can be seen from the test results in Table 3 that the water suspension concentrates (10 g / mu dosage) in Examples 1-5 can achieve a control effect of more than 70% 3 days after application, and a control effect of more than 80% 10 days after application. Among them, the 3-day and 10-day control effects of the preparation in Example 3 with a dosage of 10 g / mu are the best, with control effects of 85.3% and 95.1% respectively, which are significantly better than the control effects of the two control agents and the chemical agent control.

[0101] Field observations showed that the above-mentioned test agents and control agents were safe for the test crop sunflower, and no symptoms of pesticide damage (such as dwarfing, chlorosis, deformity, etc.) were found.

[0102] The test results of the above embodiments show that the biopesticide compound preparation of Bacillus amyloliquefaciens and Rhodomyces thiophilus has a higher short-term and long-term protective effect than the chemical agent 30% trifloxystrobin propiconazole suspension, and has excellent rapidity and persistence, overcoming the disadvantages of poor rapidity, slow protective effect and high cost of biopesticides. Since biopesticides are living preparations, it is difficult to ensure the storage, stability and activity of liquid preparations, so most preparations are solid powder preparations. Solid preparations have poor uniformity and dispersibility during use, and safety and environmental protection cannot be guaranteed. It is very inconvenient and time-consuming for farmers to use. The present invention is a liquid preparation with excellent field effect and is very convenient to use. It overcomes the disadvantages of instability of liquid preparations of biopesticides and has strong creativity.

[0103] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0104] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A fungicidal composition for preventing and controlling sunflower white rust, characterized in that: The active ingredients of the bactericidal composition are composed of Bacillus amyloliquefaciens and Oomyces sulfidophilus, wherein the gram ratio of Bacillus amyloliquefaciens to Oomyces sulfidophilus is (100) billion CFU / g: (100) billion CFU / g.

2. The bactericidal composition according to claim 1, characterized in that In the fungicidal composition, the gram ratio of Bacillus amyloliquefaciens to Rhodomyces sulfidophilus is 4 billion CFU / g:400 million CFU / g.

3. The bactericidal composition according to any one of claims 1 to 2, characterized in that The bactericidal composition also includes an adjuvant, wherein the content of the active ingredient is (100-200) billion CFU / gram.

4. The bactericidal composition according to claim 3, characterized in that The active ingredient content is 4.4 billion CFU / gram.

5. The bactericidal composition according to claim 3, characterized in that The dosage form of the bactericidal composition is a liquid preparation.

6. The bactericidal composition according to claim 5, characterized in that The liquid preparation is an aqueous suspension.

7. The bactericidal composition according to claim 3, characterized in that The adjuvant is any acceptable adjuvant in pesticide science.

8. The bactericidal composition according to claim 7, characterized in that The auxiliary agent is selected from at least one of a dispersant, a wetting agent, a preservative and a solvent.

9. Use of the fungicidal composition according to any one of claims 1 to 8 in preventing and controlling sunflower white rust.

10. The use according to claim 9, characterized in that The sunflower white rust is caused by infection by Albugo serrata.

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