Biological agent for preventing and treating wheat scab as well as preparation method and application of biological agent

Abstract

The invention discloses a biological agent for preventing and treating wheat scab as well as a preparation method and application thereof, and belongs to the technical field of plant disease prevention and treatment. The microbial agent is prepared from the following raw materials in parts by weight: 5 to 10 parts of trichoderma harzianum, 2 to 5 parts of streptomyces microflavus, 2 to 5 parts of bacillus subtilis, 75 to 90 parts of soybean meal, 0.1 to 0.5 part of vitamin B1, 2 to 5 parts of potassium fulvate and 2 to 5 parts of ferrous phosphate. The microbial agent disclosed by the invention takes trichoderma harzianum, streptomyces microflavus and bacillus subtilis as biocontrol strains, and has an inhibiting effect on fusarium sp. The microbial agent in the wheat scab prevention and treatment scheme is environment-friendly and sustainable, and the resistance and biodiversity of crops are enhanced, so that the dependence of chemical pesticides is reduced, and the agricultural ecological balance is promoted.

Description

Technical Field

[0001] The invention relates to the technical field of plant disease prevention and control, in particular to a biological bacterial agent for preventing and controlling wheat scab and a preparation method and application thereof. Background Art

[0002] The dominant pathogen of wheat fusarium asiaticum is Fusarium asiaticum. The pathogen mainly infects wheat during the flowering stage and shows symptoms during the grain filling stage. When warm and humid conditions are encountered during the heading and flowering stage of wheat, the ascospores are released, spread by air currents, wind and rain, splashed on the anthers of the withered flower organs, and infected spikelets. The climate in northern Zhejiang is humid and rainy, especially the continuous rainy weather during the heading and flowering stage of wheat, which is the most important environmental factor determining the occurrence of fusarium spores. Ear rot is the most important symptom of wheat fusarium spores. In the early stage of the disease, small water-soaked light brown spots appear on the spikelets and glumes, and then gradually expand to the entire spikelet, and the spikelet turns yellow. When the humidity is high, a pink gelatinous mold layer is produced at the lesions, and small black spots, i.e., ascospores, are densely grown on it in the later stage. Later, it extends to the spike axis, and the diseased part turns brown, causing the spikelets above the affected part to form dry white ears. Seedling rot is caused by infection of seeds with bacteria or pathogens in the soil. First, the buds turn brown, then the root crown rots. In mild cases, the seedlings become yellow and thin, and in severe cases, the seedlings die. When the disease breaks out, it can generally reduce wheat production by 10%-20%, and in severe cases, it can reduce production by 80%-90%. In addition, after being infected with fusarium head blight, mycotoxins such as deoxynivalenol (DON) and zearalenone (ZEN) will be produced in wheat grains, which not only affect the processing quality and food safety of wheat, but may also cause fever, vomiting, diarrhea and other poisoning incidents after humans and animals accidentally eat it.

[0003] At present, the prevention and control of wheat scab mainly relies on chemical fungicides. However, the prevention and control method using chemical fungicides has certain limitations. On the one hand, Fusarium graminearum invades at different stages of wheat growth and development, and different chemical agents need to be used for prevention and control, resulting in high prevention and control costs; on the other hand, when wheat encounters rain during its flowering period, chemical agents are easily washed away by rain, which seriously weakens the prevention and control effect. In addition, long-term use of chemical pesticides will also cause pathogens to develop drug resistance, pollute the environment, and destroy the ecological balance. If microbial agents are used to prevent and control wheat scab, since the stability and prevention and control effect of microbial agents are greatly affected by environmental factors, in actual applications, their shelf life is short, storage and transportation conditions are harsh, and pathogens in different regions may have different sensitivities to microbial agents. Therefore, it is of great significance to provide a biological agent that can effectively prevent and control wheat scab. Summary of the invention

[0004] The purpose of the present invention is to provide a biological agent for preventing and controlling wheat scab and its preparation method and application, so as to solve the problems existing in the above-mentioned prior art. The microbial agent in the wheat scab prevention and control scheme of the present invention is environmentally friendly and sustainable. The present invention reduces the dependence on chemical pesticides and promotes agricultural ecological balance by enhancing the resistance and biodiversity of crops themselves.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] Technical Solution 1: A microbial agent for preventing and controlling wheat fusarium rust, which is prepared from raw materials including the following parts by weight: 5-10 parts of Trichoderma harzianum, 2-5 parts of Streptomyces tenuifolius, 2-5 parts of Bacillus subtilis, 75-90 parts of soybean meal, 0.1-0.5 parts of vitamin B1, 2-5 parts of potassium humate and 2-5 parts of ferrous phosphate.

[0007] Furthermore, the microbial agent is prepared from the following raw materials in parts by weight: 7 parts of Trichoderma harzianum, 4 parts of Streptomyces tenuifolius, 3 parts of Bacillus subtilis, 80 parts of soybean meal, 0.3 parts of vitamin B1, 3 parts of potassium humate and 3 parts of ferrous phosphate.

[0008] Furthermore, the bacterial content of the Trichoderma harzianum is 7-10 billion CFU / g; the bacterial content of the Streptomyces tenuifolius is 5-9 billion CFU / g; and the bacterial content of the Bacillus subtilis is 5-9 billion CFU / g.

[0009] Furthermore, the bacterial content of the Trichoderma harzianum is 9 billion CFU / g; the bacterial content of the Streptomyces tenuifolius is 7 billion CFU / g; and the bacterial content of the Bacillus subtilis is 6 billion CFU / g.

[0010] Furthermore, the microbial agent is applied during the heading and flowering period of wheat.

[0011] Technical Solution 2: A method for preparing the microbial agent, comprising uniformly mixing the Trichoderma harzianum, the Streptomyces tenuifolius and the Bacillus subtilis with the soybean meal, and then adding the vitamin B1, the potassium humate and the ferrous phosphate, and mixing to obtain the microbial agent.

[0012] Technical solution three: Application of the microbial agent in preventing and controlling wheat fusarium rust.

[0013] Technical Solution 4: Application of the microbial agent in the preparation of biocontrol drugs for preventing and controlling wheat fusarium head blight.

[0014] Technical Solution 5: A biocontrol drug for preventing and treating wheat fusarium rust, comprising the microbial agent.

[0015] Technical Solution 6: A method for preventing and controlling wheat fusarium rust, comprising the step of applying the microbial agent during the heading and flowering period of wheat.

[0016] The present invention discloses the following technical effects:

[0017] The invention provides a microbial agent for preventing and treating wheat fusarium head blight. The microbial agent is composed of Trichoderma harzianum, Streptomyces tenuifolius and Bacillus subtilis. The three microorganisms have different action mechanisms. Trichoderma harzianum can parasitize or produce antibacterial substances to inhibit pathogens, Streptomyces tenuifolius can produce abundant secondary metabolites, and Bacillus subtilis can produce anti-active substances. They cooperate with each other to more comprehensively inhibit the growth, reproduction and infection of wheat fusarium head blight pathogens and improve the prevention and control effect. Specifically, Trichoderma harzianum can promote the growth of wheat seedlings and improve the disease resistance of wheat; Bacillus subtilis can promote the absorption of nutrients in the soil for wheat; Streptomyces tenuifolius can secrete plant hormones such as auxin and cytokinin during metabolism. Auxin can promote the elongation and division of cells, increase the volume and number of wheat root cells, thereby promoting the growth and elongation of the root system; cytokinin can stimulate cell division, increase the activity of root meristems, promote the formation of new roots and the branching of the root system, and make the root system more developed. Soybean meal is a byproduct obtained after soybean oil is extracted from soybeans. It is rich in nutrients such as protein, fat, and minerals. While providing nutrition, it can also serve as a carrier and adsorbent for microorganisms. Potassium humate has the functions of improving soil structure, increasing soil fertility, and promoting plant growth. It can also provide a suitable living environment for microorganisms and enhance the effect of microbial agents. Ferrous phosphate can be added to fertilizers or soil conditioners as a nutrient supplement to provide iron for wheat growth, enhance wheat's stress resistance, and indirectly improve its resistance to ergot. Vitamin B1 can provide additional nutrition and stimulation for wheat, improve wheat's stress resistance and immunity, and enhance the inhibitory effect on ergot pathogens.

[0018] Compared with chemical pesticides, the microbial agent provided by the present invention is more environmentally friendly, does not cause pesticide residues and environmental pollution, and can reduce the use of chemical pesticides, reduce production costs, and also help maintain the balance and biodiversity of farmland ecosystems. The microbial agent in the wheat fusarium rust control scheme of the present invention is environmentally friendly and sustainable. The present invention reduces the dependence on chemical pesticides and promotes agricultural ecological balance by enhancing the resistance and biodiversity of crops themselves. It can also be used as an eco-friendly substitute to reduce the use of traditional chemical pesticides, thereby reducing their impact on the environment and ecosystem, and has broad prospects in the field of agricultural production. DETAILED DESCRIPTION

[0019] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0020] It should be understood that the terms described in the present invention are only for describing a particular embodiment and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. The intermediate value in any stated value or stated range, and each smaller range between any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0021] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0022] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present invention description and examples are exemplary only.

[0023] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0024] The strains involved in this example were sourced as follows: Trichoderma harzianum CICC41290 was purchased from China Industrial Microbiological Culture Collection Center; Streptomyces microflavus was purchased from Shandong Hezhong Kangyuan Biotechnology Co., Ltd.; Bacillus subtilis was purchased from Shanghai Gaoming Chemical Co., Ltd. Other reagents and materials not specifically described can be obtained by those skilled in the art through conventional purchase.

[0025] Example 1

[0026] A microbial agent for preventing and treating wheat scab, the specific preparation process is as follows:

[0027] Preparation: Ensure the operating environment is clean and sterile, prepare the necessary utensils and containers, and measure and prepare each ingredient according to the required amount;

[0028] Preparation process: 7 parts of Trichoderma harzianum, 4 parts of Streptomyces tenuifolius and 3 parts of Bacillus subtilis are mixed with 80 parts of soybean meal by weight, and 0.3 parts of vitamin B1, 3 parts of potassium humate and 3 parts of ferrous phosphate are added and mixed again to obtain a microbial agent. Among them, the bacterial content of Trichoderma harzianum is 9 billion CFU / g; the bacterial content of Streptomyces tenuifolius is 7 billion CFU / g; and the bacterial content of Bacillus subtilis is 6 billion CFU / g.

[0029] Storage: Avoid exposing the microbial agent to direct sunlight or extreme temperature conditions. Store in a dry, cool place and avoid contact with other chemicals.

[0030] Example 2

[0031] A microbial agent for preventing and treating wheat scab, the specific preparation process is as follows:

[0032] Preparation: Ensure the operating environment is clean and sterile, prepare the necessary utensils and containers, and measure and prepare each ingredient according to the required amount;

[0033] Preparation process: 5 parts of Trichoderma harzianum, 2 parts of Streptomyces tenuifolius and 2 parts of Bacillus subtilis are mixed with 75 parts of soybean meal by weight, and 0.1 parts of vitamin B1, 2 parts of potassium humate and 2 parts of ferrous phosphate are added and mixed again to obtain a microbial agent. Among them, the bacterial content of Trichoderma harzianum is 7 billion CFU / g; the bacterial content of Streptomyces tenuifolius is 5 billion CFU / g; and the bacterial content of Bacillus subtilis is 5 billion CFU / g.

[0034] Storage: Avoid exposing the microbial agent to direct sunlight or extreme temperature conditions. Store in a dry, cool place and avoid contact with other chemicals.

[0035] Example 3

[0036] A microbial agent for preventing and treating wheat scab, the specific preparation process is as follows:

[0037] Preparation: Ensure the operating environment is clean and sterile, prepare the necessary utensils and containers, and measure and prepare each ingredient according to the required amount;

[0038] Preparation process: 10 parts of Trichoderma harzianum, 5 parts of Streptomyces tenuifolius and 5 parts of Bacillus subtilis are mixed with 90 parts of soybean meal by weight, and 0.5 parts of vitamin B1, 5 parts of potassium humate and 5 parts of ferrous phosphate are added and mixed again to obtain a microbial agent. Among them, the bacterial content of Trichoderma harzianum is 10 billion CFU / g; the bacterial content of Streptomyces tenuifolius is 9 billion CFU / g; and the bacterial content of Bacillus subtilis is 9 billion CFU / g.

[0039] Storage: Avoid exposing the microbial agent to direct sunlight or extreme temperature conditions. Store in a dry, cool place and avoid contact with other chemicals.

[0040] Comparative Example 1

[0041] The difference between this comparative example and Example 1 is that Bacillus subtilis is omitted, and other operations are the same as those in Example 1.

[0042] Comparative Example 2

[0043] The difference between this comparative example and Example 1 is that Streptomyces tenuiflavus is omitted, and other operations are the same as those in Example 1.

[0044] Comparative Example 3

[0045] The difference between this comparative example and Example 1 is that Trichoderma harzianum is omitted, and other operations are the same as those in Example 1.

[0046] Comparative Example 4

[0047] The difference between this comparative example and Example 1 is that potassium humate is omitted, and other operations are the same as those in Example 1.

[0048] Comparative Example 5

[0049] The difference between this comparative example and Example 1 is that ferrous phosphate is omitted, and other operations are the same as those in Example 1.

[0050] Comparative Example 6

[0051] The difference between this comparative example and Example 1 is that the preparation process of this comparative example is as follows: by weight, 11 parts of Trichoderma harzianum, 6 parts of Streptomyces tenuifolius and 6 parts of Bacillus subtilis are mixed with 70 parts of soybean meal, 0.6 parts of vitamin B1, 1 part of potassium humate and 6 parts of ferrous phosphate are added and mixed again, and a microbial agent is obtained after mixing. Other operations are the same as those in Example 1.

[0052] Comparative Example 7

[0053] The difference between this comparative example and Example 1 is that in the preparation process of this comparative example, the bacterial content of Trichoderma harzianum is 11 billion CFU / g; the bacterial content of Streptomyces tenuifolius is 10 billion CFU / g; and the bacterial content of Bacillus subtilis is 4 billion CFU / g. Other operations are the same as in Example 1.

[0054] Test Example 1

[0055] This test example uses an indoor potted plant experiment to test the control effect of the microbial agents of each group (Examples 1-3 and Comparative Examples 1-7) on wheat fusarium wilt and the colonization effect of the biocontrol bacteria (Trichoderma harzianum, Streptomyces tenuifolius and Bacillus subtilis). The specific process is as follows:

[0056] The test soil was sterilized at 121°C for 2 h and then dried. 5 CFU / g dry soil. The test soil was moved into the pot and the moisture of the test soil was adjusted to 60%. The microbial agents of each group were added at a rate of 1×10 5 CFU / g dry soil (the same number of bacterial agents were applied in this test case to facilitate result analysis) was applied to the pots, the wheat seeds were disinfected, and then 10 wheat seeds were sown per tray. In addition, a blank control group and a positive control group were set up. The blank control group was neither inoculated with pathogens nor microbial agents, and the positive control group was only inoculated with pathogens. Each group was set up with 3 replicates. Under the conditions of 20℃ and soil moisture content of 19%, the wheat emergence rate was counted 10 days after sowing, as shown in Table 1.

[0057] At the same time, the soil below 5 cm from the surface of the potted plants was taken on the 1st, 7th and 20th day after sowing, and the dilution plate counting method was used to count the number of Fusarium asiatica and biocontrol bacteria in Example 1, Comparative Example 3 and Comparative Example 6 with obvious statistical effects, as shown in Table 2. The statistical results were averaged.

[0058] The statistical results of wheat emergence rate are shown in Table 1.

[0059] Table 1 Wheat germination rate in each group

[0060]

[0061]

[0062] Table 1 shows that fusarium head blight can reduce the emergence rate of wheat. The microbial agents of Examples 1-3 can improve the emergence rate of wheat by inhibiting pathogens, reaching a state similar to that of the blank control group. When certain raw materials are omitted and the dosage is adjusted, the inhibitory effect of the microbial agent on pathogens decreases, and the improvement effect on the emergence rate of wheat decreases. When Trichoderma harzianum, Streptomyces tenuifolius and Bacillus subtilis are added to the microbial agent together, the wheat emergence improvement effect is obvious.

[0063] The statistical numbers of Fusarium asiatica and biocontrol bacteria are shown in Table 2.

[0064] Table 2 Statistical number of Fusarium asiatica and biocontrol bacteria in each group of soil

[0065]

[0066] Table 2 shows that on the first day after inoculation / sowing, pathogens and biocontrol strains showed a downward trend, while on the 7th and 20th days, they showed an upward trend, which indicates that the microorganisms of the present invention need to gradually adapt to the complex soil environment. However, according to Example 1, Comparative Examples 3 and 6, it can be seen that only when Trichoderma harzianum, Streptomyces tenuifolius and Bacillus subtilis are added to the microbial agent in a specific ratio, can the adaptability of the biocontrol strains be effectively improved and their colonization rate be increased; the effect of adding them alone is significantly lower than the effect of the three together.

[0067] In summary, the microbial agent of the present invention has an inhibitory effect on Fusarium asiatica. When Trichoderma harzianum, Streptomyces tenuifolius and Bacillus subtilis are added to the microbial agent together, the wheat emergence rate is significantly improved.

[0068] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A microbial agent for preventing and treating wheat scab, characterized in that: The microbial agent is prepared from the following raw materials in parts by weight: 5-10 parts of Trichoderma harzianum, 2-5 parts of Streptomyces tenuifolius, 2-5 parts of Bacillus subtilis, 75-90 parts of soybean meal, 0.1-0.5 parts of vitamin B1, 2-5 parts of potassium humate and 2-5 parts of ferrous phosphate.

2. The microbial agent according to claim 1, characterized in that The microbial agent is prepared from the following raw materials in parts by weight: 7 parts of Trichoderma harzianum, 4 parts of Streptomyces tenuifolius, 3 parts of Bacillus subtilis, 80 parts of soybean meal, 0.3 parts of vitamin B1, 3 parts of potassium humate and 3 parts of ferrous phosphate.

3. The microbial agent according to claim 1, characterized in that: The bacterial content of the Trichoderma harzianum is 7-10 billion CFU / g; the bacterial content of the Streptomyces tenuifolius is 5-9 billion CFU / g; and the bacterial content of the Bacillus subtilis is 5-9 billion CFU / g.

4. The microbial agent according to claim 3, characterized in that: The bacterial content of the Trichoderma harzianum is 9 billion CFU / g; the bacterial content of the Streptomyces tenuifolius is 7 billion CFU / g; and the bacterial content of the Bacillus subtilis is 6 billion CFU / g.

5. The microbial agent according to any one of claims 1 to 4, characterized in that: The microbial agent is applied during the heading and flowering period of wheat.

6. A method for preparing the microbial agent according to any one of claims 1 to 4, characterized in that: The method comprises the steps of uniformly mixing the Trichoderma harzianum, the Streptomyces tenuifolius and the Bacillus subtilis with the soybean meal, then adding the vitamin B1, the potassium humate and the ferrous phosphate, and mixing them to obtain the microbial agent.

7. Use of the microbial agent according to any one of claims 1 to 4 in preventing and controlling wheat fusarium head blight.

8. Use of the microbial agent according to any one of claims 1 to 4 in the preparation of a biocontrol agent for preventing and controlling wheat fusarium head blight.

9. A biocontrol drug for preventing and controlling wheat scab, characterized in that: The microbial agent comprises the microbial agent according to any one of claims 1 to 4.

10. A method for preventing and controlling wheat scab, characterized in that: The method comprises the step of applying the microbial agent according to any one of claims 1 to 4 during the heading and flowering period of wheat.

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