Trichobacter sp. With phytopathogen resisting and plant growth promoting effects and application of Trichobacter sp.

Abstract

The invention relates to a Tarromyces sp. Strain and application thereof, the Tarromyces sp. Strain is named as Tarromyces sp. Strain F19, the preservation number is GDMCC No: 65365, and the preservation date is October 28, 2024. The Tarromyces sp. Strain is named as Tarromyces sp. Strain F19, the preservation number is GDMCC No: 65365, and the preservation date is October 28, 2024. According to the invention, a new strain of cyanobacteria with phytopathogen resisting and plant growth promoting effects is separated from rhizosphere soil of corn and is preserved, and the strain has a remarkable inhibition effect on various phytopathogens such as fusarium oxysporum, phytophthora nicotianae or Kleiella solani, and can be used as a biocontrol bacterium for preventing and treating various plant diseases; in addition, the strain can also be used for plant growth promotion. The strain resources of the biocontrol bacteria are enriched, and the method can be applied to the development of biopesticides.

Description

Technical Field

[0001] The invention belongs to the technical field of agricultural microorganisms and relates to a blue fungus with the functions of resisting plant pathogens and promoting plant growth and application thereof. Background Art

[0002] Soil-borne diseases are an increasingly serious problem in modern agricultural production. This is mainly due to the accumulation of plant root metabolites in the soil caused by continuous cropping, which provides a good growth and reproduction environment for soil-borne fungal diseases. Among them, Fusarium, Phytophthora and Ralstonia are three important soil-borne pathogenic fungi, which can cause wilt and blight symptoms in crops and vegetables, seriously affecting crop production and causing significant economic losses.

[0003] Fusarium oxysporum is a widely distributed soil-borne pathogenic fungus with a very wide host range. It can cause wilt in more than 100 species of plants, including cucurbits, solanaceae, and legumes. Infection by Fusarium oxysporum can cause browning of plant vascular bundles, wilting and death of plants, rot of bulbs and roots, and weak growth of plants. These symptoms develop most rapidly and seriously during high temperatures in summer. Fusarium oxysporum wilt poses a major threat to agricultural production, especially in areas where crops are continuously cropped, which directly affects the yield and economic benefits of crops.

[0004] There are many types of Phytophthora, among which tobacco black shank caused by Phytophthora nicotianae is an important soil-borne fungal disease that mainly infects the roots and stem base of tobacco, forming black sunken lesions. This disease is distributed worldwide, especially in temperate, subtropical and tropical regions.

[0005] Ralstonia solanacearum is an important plant pathogenic bacterium that has caused serious economic losses to agricultural production, especially Solanaceae crops, worldwide. In my country, Ralstonia solanacearum is also an important soil-borne disease of tobacco. Therefore, the management and prevention of these soil-borne diseases is an important issue in agricultural production.

[0006] At present, the prevention and control of diseases caused by plant pathogens mainly rely on chemical pesticides. However, excessive use of chemical agents will not only lead to excessive pesticide residues in agricultural products, endangering the health of consumers, but may also cause environmental pollution and damage to the ecological balance, affecting the sustainable development of agriculture. Therefore, it is necessary to seek more environmentally friendly and sustainable prevention and control methods. As an important plant disease prevention and control measure, biological control prevents or alleviates diseases by inducing disease resistance in host plants or by antagonizing pathogenic fungi. Biological agents or preparations can reduce or replace the use of chemical pesticides, effectively prevent and control diseases, and avoid the negative effects of chemical pesticides. This method not only helps to protect the environment, but also maintains ecological balance and promotes the sustainable development of agriculture. Summary of the invention

[0007] In view of the shortcomings of the prior art, the object of the present invention is to provide a blue fungus with anti-plant pathogenic bacteria and plant growth-promoting effects and its application.

[0008] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0009] In the first aspect, the present invention provides a blue fungus with anti-plant pathogenic bacteria and plant growth-promoting effects. The blue fungus is named as Talaromyces sp. F19 strain, with a preservation number of GDMCC No: 65365 and a preservation date of October 28, 2024.

[0010] The present invention isolates and preserves a new strain of Talaromyces sp. F19 strain that has anti-plant pathogenic bacteria and plant growth-promoting effects from corn rhizosphere soil. The strain has a significant inhibitory effect on a variety of plant pathogenic bacteria such as Fusarium oxysporum, Phytophthora nicotianae or Ralstonia solanacearum, and can be used as a biocontrol bacterium to control a variety of plant diseases; secondly, the bacterium can also be used for plant growth promotion. The present invention enriches the strain resources of biocontrol bacteria and can be applied to the development of biological pesticides.

[0011] In a second aspect, the present invention provides a bacterial agent having the effects of resisting plant pathogens and promoting plant growth, wherein the strain in the bacterial agent includes the Talaromyces sp. F19 strain described in the first aspect.

[0012] Preferably, the dosage form of the bacterial agent includes solution, powder, tablet or capsule.

[0013] In a third aspect, the present invention provides use of the blue bacteria described in the first aspect or the bacterial agent described in the second aspect in the preparation of a plant pathogen inhibitor.

[0014] Preferably, the plant pathogenic bacteria include any one of Fusarium oxysporum, Phytophthora nicotianae or Ralstonia solanacearum, or a combination of at least two thereof.

[0015] The F19 strain involved in the present invention has significant inhibitory effects on various plant pathogens, and has excellent inhibitory effects on Fusarium oxysporum, Phytophthora nicotianae and Ralstonia solanacearum, and can be used as a biocontrol bacterium to prevent and control various plant diseases caused by the above pathogens.

[0016] In a fourth aspect, the present invention provides use of the blue fungus described in the first aspect or the bacterial agent described in the second aspect in preventing and controlling plant diseases caused by soil-borne pathogens.

[0017] Preferably, the soil-borne pathogens include any one of Fusarium oxysporum, Phytophthora nicotianae or Ralstonia solanacearum, or a combination of at least two thereof.

[0018] Preferably, the plant comprises tobacco.

[0019] In a fifth aspect, the present invention provides the use of the blue bacteria described in the first aspect or the bacterial agent described in the second aspect in the preparation of a plant growth-promoting preparation.

[0020] Preferably, the plant comprises corn.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention isolates and preserves a new strain of Talaromyces sp. F19 strain that has anti-plant pathogenic bacteria and plant growth-promoting effects from corn rhizosphere soil. The strain has a significant inhibitory effect on a variety of plant pathogenic bacteria such as Fusarium oxysporum, Phytophthora nicotianae or Ralstonia solanacearum, and can be used as a biocontrol bacterium to control a variety of plant diseases; secondly, the bacterium can also be used for plant growth promotion. The present invention enriches the strain resources of biocontrol bacteria and can be applied to the development of biological pesticides. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is the colony picture of the blue bacteria F19 strain;

[0024] Figure 2 This is the genetic phylogenetic tree diagram of the F19 strain of the blue bacteria;

[0025] Figure 3 This is a graph showing the inhibitory effect of the Blue Fungus F19 strain on Fusarium oxysporum;

[0026] Figure 4 This is a graph showing the inhibitory effect of the blue fungus F19 strain on tobacco phytophthora;

[0027] Figure 5This is a graph showing the inhibitory effect of the blue fungus F19 strain on Ralstonia solanacearum;

[0028] Figure 6 This is a statistical graph showing the growth-promoting effect of the blue fungus F19 strain on corn seedlings.

[0029] The F19 strain involved in the present invention is classified and named Talaromyces sp., and is preserved in the Guangdong Provincial Microbiological Culture Collection Center. Its preservation number is GDMCC No: 65365, the preservation date is October 28, 2024, and the preservation address is 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou. DETAILED DESCRIPTION

[0030] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0031] Example 1

[0032] Isolation, screening and identification of strains:

[0033] (1) Isolation of strains:

[0034] In July 2021, 10 samples of corn rhizosphere soil were selected, transferred to sterile saline, and broken up by adding glass beads. -3 ~10 -6 times, take 100 μL respectively and spread on red Bengal agar medium (5 g / L peptone, 10 g / L glucose, 1 g / L potassium dihydrogen phosphate, 0.5 g / L magnesium sulfate, 15 g / L agar, 0.03 g / L red Bengal, 0.1 g / L chloramphenicol, final pH = 7.2 ± 0.2), pick a single colony, and use potato dextrose agar (PDA) medium (6 g / L potato powder, 20 g / L glucose, 20 g / L agar, fixed to 1000 ml, natural pH), and purify three times.

[0035] (2) Screening of strains:

[0036] Single colonies were picked, and the single colonies and Fusarium oxysporum, Phytophthora nicotianae, and Ralstonia solanacearum were inoculated on PDA plates using the plate confrontation growth method and cultured at 28°C. Fusarium oxysporum was isolated from the rhizosphere of corn, and Phytophthora nicotianae and Ralstonia solanacearum were isolated from the rhizosphere of tobacco. The inhibition rate of mycelial growth of each colony on plant pathogens was calculated, and the radial growth length of the pathogen was measured with a ruler and the inhibition rate was calculated. The calculation is as follows: [(R1-R2) / R1]×100%, where R1 is the colony diameter of the control group, and R2 is the colony diameter of the pathogen under dual culture with the strain to be tested. A strain with strong inhibition on the growth of Fusarium oxysporum, Phytophthora nicotianae, and Ralstonia solanacearum was screened out and named F19.

[0037] (3) Identification of morphological characteristics of strains:

[0038] The strain F19 isolated above was cultured on a PDA plate at 25°C for 7 days, and the color and morphological characteristics of the colonies were observed and recorded. It was found that the colonies were yellow in the middle and cyan at the edges, and produced a large number of conidia, such as Figure 1 shown.

[0039] (4) Biomolecular identification of strains:

[0040] DNA of the strain was extracted and PCR sequence determination was performed using universal primers ITS1 / ITS4. The PCR amplification product was sent to Shanghai Paisono Company for sequencing. After sequencing, the ITS fragment sequence of the F19 strain was shown in the sequence SEQ ID NO.1; after comparison with the NCBI database, the sequence matching rate between the strain F19 to be tested and Talaromyces verruculosu (GenBank: KF221083.1) was 99.81%. By establishing a phylogenetic tree, as shown in FIG. Figure 2 As shown, it can be seen that F19 belongs to the genus Ceratocystis. The strain F19 was deposited in Guangdong Microbiological Culture Collection Center with the deposit number GDMCC No: 65365.

[0041] Example 2

[0042] Evaluation of the antibacterial effect of F19 strain on plant pathogens:

[0043] (1) Inoculate F19 strain and Fusarium oxysporum on PDA plates respectively, activate and culture at 28℃ for 4 days for use; then inoculate Fusarium oxysporum in the center of the plate and inoculate F19 strain at four opposite corners of the plate as the treatment group, and inoculate only Fusarium oxysporum on the plate as the control group, and then invert the culture dish in an incubator for culture. After 10 days of culture, observe the growth of mycelium in each group. Figure 3As shown, the inhibition rate was calculated as follows: [(R1-R2) / R1]×100%, where R1 is the colony diameter of Fusarium oxysporum in the control group, and R2 is the colony diameter of Fusarium oxysporum in the treatment group. It was calculated that the inhibition rate of the mycelial growth of Fusarium oxysporum by the F19 strain was 54.7%.

[0044] (2) Inoculate F19 strain and Phytophthora nicotianae on PDA plates respectively, activate and culture at 28℃ for 4 days for use; then inoculate Phytophthora nicotianae in the center of the plate and inoculate F19 strain at four diagonal corners of the plate as the experimental group, and the plate inoculated with only Phytophthora nicotianae as the control group, and then invert the culture dish in an incubator for culture. After 10 days of culture, observe the growth of mycelium in each group. Figure 4 As shown, the inhibition rate was calculated as follows: [(R1-R2) / R1]×100%, where R1 is the colony diameter of tobacco phytophthora in the control group, and R2 is the colony diameter of tobacco phytophthora in the experimental group. It was calculated that the mycelial growth inhibition rate of F19 strain to tobacco phytophthora was 62.2%.

[0045] (3) First, Ralstonia solanacearum was isolated at a rate of about 10 7 The concentration of 100 / mL was evenly spread on the PDA plate, and then F19 hyphae were picked from the PDA plate and inoculated in the center of the plate. Then the culture dish was inverted and cultured in an incubator for 10 days. The growth of the strain was observed. Figure 5 As shown, it can be seen that the F19 strain also has an obvious inhibition zone against Ralstonia solanacearum.

[0046] Example 3

[0047] Evaluation of the effect of F19 strain on plant growth promotion:

[0048] The experimental group and the control group were set up. The experimental group was as follows: the corn seeds were sterilized and soaked for 7 hours, and germinated in the dark at 25°C for 3 days. The corn seeds with the same germination degree were planted in pots (1 kg soil / pot). The spores of strain F19 were directly scraped from the plate and adjusted to 10 6 / ml, 20mL spore liquid was directly poured into each pot, and 20mL pure water was poured into the control group. After 14 days of cultivation in the greenhouse, the average plant height, average root length, average root fresh weight and average plant fresh weight of corn were measured respectively.

[0049] The results are as follows Figure 6 As shown, compared with the control group, strain F19 can increase the plant height and root length of corn plants, and can also increase the plant weight and root weight of corn plants. This shows that strain F19 is harmless to plants and has a significant growth-promoting effect.

[0050] Example 4

[0051] Evaluation of the control effect of F19 strain on plant diseases:

[0052] (1) First, rice grains were placed in distilled water and boiled at high temperature until 2 / 3 of the grains were bloomed. After the water was drained with gauze, the rice grains were placed in a 500 mL conical flask and sterilized under high pressure (121°C, 1 h). At the same time, tobacco phytophthora was inoculated on a PDA plate and activated and cultured at 28°C for 7 days. The tobacco phytophthora hyphae was directly picked up with an inoculation loop and inoculated into the millet treated as above. After culturing at 28°C for 15 days, the tobacco phytophthora millet was air-dried at room temperature and set aside.

[0053] (2) The F19 strain was inoculated into a PDA liquid medium and cultured at 28°C for 7 days. The experimental soil was collected from a farmland (red soil) in Chenggong, Kunming, Yunnan. The tobacco phytophthora ...

[0054] The Yunyan 87 seedlings with basically uniform growth and 5 true leaves were transplanted into pots containing 500 g of soil (one plant per pot). Two treatments were set up: (1) CK group (control group, 10 mL of water was poured into the roots of the tobacco seedlings); (2) F19 inoculation group (spores of strain F19 were scraped from the plate and adjusted to 10 6 Each treatment was repeated 3 times, with 9 pots in each repeat. The plants were cultured in a light incubator at 28°C and a relative humidity of 70%.

[0055] On the 8th day after transplanting, the disease grade and incidence rate were counted, and the disease index and disease prevention effect were calculated. The classification standard of tobacco black shank disease is as follows: Grade 0, the whole plant is disease-free; Grade 1, the stem lesions do not exceed 1 / 3 of the stem circumference, or less than 1 / 3 of the leaves wilt; Grade 3, the stem lesions surround 1 / 2 to 2 / 3 of the stem circumference, or 1 / 3 to 1 / 2 of the leaves are slightly withered; Grade 5: the stem lesions exceed 1 / 2 of the stem circumference, but do not completely surround the stem circumference, or 1 / 2 to 2 / 3 of the leaves wilt; Grade 7, the stem lesions completely surround the stem circumference, or more than 2 / 3 of the leaves wilt; Grade 9: the diseased plants are basically dead. Incidence rate = (number of diseased plants / total number of inoculated plants) × 100%; Disease index = [(number of plants at each disease level × representative level value) / (total number of plants × representative level value of the highest disease level)] × 100; Control effect = [(control disease index - treatment disease index) / control disease index] × 100%.

[0056] The test results showed that the disease index of the CK group was 83.65, the disease index of the F19 inoculated group was 25.28, and the relative control efficiency was 69.78%, indicating that the F19 strain involved in the present invention can prevent and control plant diseases caused by soil-borne pathogens.

[0057] The applicant declares that the present invention illustrates the technical solution of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0058] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0059] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

Claims

1. A blue fungus having anti-plant pathogenic bacteria and plant growth-promoting effects, characterized in that: The blue bacteria is named as Talaromyces sp. F19 strain, the preservation number is GDMCC No: 65365, and the preservation date is October 28, 2024.

2. A fungal agent having anti-plant pathogenic bacteria and plant growth-promoting effects, characterized in that: The strain in the bacterial agent includes the Talaromyces sp. F19 strain described in claim 1.

3. The bacterial agent according to claim 2, characterized in that The dosage form of the bacterial agent includes solution, powder, tablet or capsule.

4. Use of the blue bacteria according to claim 1 or the bacterial agent according to claim 2 or 3 in the preparation of plant pathogen inhibitors.

5. The use according to claim 4, characterized in that: The plant pathogenic bacteria include any one of Fusarium oxysporum, Phytophthora nicotianae or Ralstonia solanacearum, or a combination of at least two thereof.

6. Use of the blue fungus according to claim 1 or the bacterial agent according to claim 2 or 3 in preventing and controlling plant diseases caused by soil-borne pathogens.

7. The use according to claim 6, characterized in that: The soil-borne pathogenic bacteria include any one of Fusarium oxysporum, Phytophthora nicotianae or Ralstonia solanacearum, or a combination of at least two thereof.

8. The use according to claim 6, characterized in that: The plants include tobacco.

9. Use of the blue bacteria according to claim 1 or the bacterial agent according to claim 2 or 3 in the preparation of a plant growth-promoting preparation.

10. The use according to claim 9, characterized in that: The plants include corn.

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