Application of pseudomonas paraxanthomonas YC15 strain in efficient prevention and treatment of wheat stem rot and various pathogenic bacteria

Abstract

The invention provides application of a pseudomonas parabarium YC15 strain in efficient prevention and treatment of wheat stem rot and various pathogenic bacteria. The invention provides a new application of the pseudomonas parabarium YC15 strain in prevention and control of plant diseases, and research shows that the YC15 strain has broad-spectrum bacteriostatic activity, has remarkable inhibitory activity on various plant pathogenic bacteria, can inhibit pathogenic fungi such as wheat stem rot, sesame root rot and colletotrichum gloeosporioides, and has a wide application prospect in prevention and control of plant diseases. And the compound has a relatively good inhibition effect on pathogenic bacteria, namely sesames pseudomonas solanacearum. The YC15 strain is applied to prevention and control of wheat stem rot, and pot experiments show that after the YC15 strain is adopted for treatment, plant lesions can be reduced, the inhibition effect of pathogenic bacteria on plants can be broken, the pathogenic bacteria can be effectively inhibited, plant growth can be promoted, and the wheat stem rot can be efficiently prevented and controlled. The invention provides new application of the YC15 strain, and the YC15 strain can be used for preventing and treating various plant protobacteria and diseases thereof, and has good development and application potential as a biocontrol bacterium.

Description

Technical Field

[0001] The invention belongs to the technical field of agricultural microorganisms, and more specifically, relates to the application of Pseudomonas paraxanthinus YC15 strain in the efficient prevention and treatment of wheat stem base rot and various pathogens. Background Art

[0002] At present, plant diseases caused by pathogenic microorganisms seriously threaten agricultural production, leading to a decrease in crop yield and quality, and causing losses to agricultural production. In order to reduce the loss of crops, efficient and safe prevention and control measures against pathogenic microorganisms are the key to controlling the occurrence and spread of plant diseases.

[0003] Wheat is the most important food crop in the world, and the safe production of wheat is of great significance to ensuring food security. Stem rot is an important soil-borne disease in wheat production caused by Fusarium pseudograminearum. Affected by factors such as climate, variety renewal, straw return to the field, and tillage system, it has shown a trend of increasing spread in some wheat-producing areas and has now become one of the main diseases in wheat-producing areas such as the Huanghuaihai area. Since most of the wheat varieties currently promoted in production are susceptible to wheat stem rot, there are no disease-resistant varieties available. At the same time, although the implementation of refined agricultural management measures has a certain control effect on the disease, since there is no registered fungicide specifically for the prevention and control of wheat stem rot in my country, the screening and prevention and control research of fungicides for wheat stem rot has become an important task for the majority of plant protection workers.

[0004] In the field of modern agricultural biological control, endophytes have attracted much attention because of their ability to promote the growth and development of host plants (nutrient acquisition, production of plant hormones, etc.) and their biological control potential (such as the production of antibiotics, lytic enzymes and other antibacterial substances). In addition, biocontrol agents are environmentally friendly, ecologically safe, and harmless to natural enemies. Biocontrol agents prepared using antagonistic bacteria are the best alternative to chemical agents. It can be seen that biological control measures are the development direction and important means of plant disease prevention and control. They have very broad application prospects in agricultural production and are of great significance to ensuring the healthy and sustainable development of agricultural production. However, there is still a lack of biocontrol agents that can effectively, broadly and safely prevent and control a variety of plant diseases including wheat stem rot. In order to further expand the bacterial resources that can prevent and control a variety of pathogenic microorganisms, it is necessary to develop or explore more strains that can be used to prevent and control a variety of pathogenic microorganisms, and provide safer and more efficient means and approaches for the prevention and control of a variety of plant diseases. Summary of the invention

[0005] The technical problem to be solved by the invention is to overcome the shortcomings of existing strains capable of preventing and treating a variety of pathogenic microorganisms, and to provide a new application of Pseudomonas parafulva YC15 strain.

[0006] The present invention aims to provide application of Pseudomonas paraxanthinus YC15 strain or its bacterial solution in inhibiting plant pathogenic fungi.

[0007] Another object of the present invention is to provide a method for controlling pathogenic fungi / bacteria or plant diseases caused by them.

[0008] The above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0009] The present invention provides a new application of Pseudomonas parafulva YC15 strain in the prevention and control of plant diseases. The YC15 strain has been preserved in the Guangdong Provincial Microbial Culture Collection Center on January 5, 2024, with the strain number GDMCC No: 64249, and the preservation address is 5th Floor, Building 59, No. 100, Xianlie Middle Road, Guangzhou. Studies have shown that the YC15 strain has a broad spectrum of antibacterial activity, has significant inhibition on a variety of plant pathogens, can inhibit pathogenic fungi wheat stem rot fungi, sesame root rot fungi, and fruit anthracnose fungi, and the inhibition rates are 65.62%, 53.08%, and 37.72%, respectively, and has a good inhibitory effect on pathogenic bacteria sesame bacterial wilt fungi. YC15 strain is used in the prevention and control of wheat stem rot. Potted plant experiments show that treatment with YC15 strain can reduce plant lesions, increase wheat germination rate, break the inhibitory effect of pathogens on plants, effectively inhibit pathogens, promote plant growth, and effectively prevent and control wheat stem base rot. The present invention provides a new application of YC15 strain, which can be used to prevent and control a variety of plant pathogens and their diseases, and has good development and application potential as a biocontrol bacterium.

[0010] Therefore, the present invention provides the use of the Pseudomonas paraxanthinus YC15 strain or its bacterial solution in inhibiting plant pathogenic fungi.

[0011] Preferably, the plant pathogenic fungus is selected from one or more of Fusarium pseudograminearum, Fusariumsolani, and Colletotrichum fructicola.

[0012] The present invention provides application of a Pseudomonas paraxanthinosus YC15 strain or a bacterial solution thereof in preventing and controlling plant diseases caused by plant pathogenic fungi.

[0013] Preferably, the plant pathogenic fungus is selected from one or more of Fusarium pseudograminearum, Fusariumsolani, and Colletotrichum fructicola.

[0014] More preferably, the plant diseases are one or more of wheat stem rot, sesame root rot, and fruit anthracnose.

[0015] The invention provides application of Pseudomonas paraxanthinus YC15 strain or bacterial liquid thereof in inhibiting plant pathogenic bacteria.

[0016] The present invention provides application of a Pseudomonas paraxanthinosus YC15 strain or a bacterial solution thereof in preventing and controlling plant diseases caused by plant pathogenic bacteria.

[0017] Preferably, the plant pathogenic bacterium is Ralstonia solanacearum.

[0018] More preferably, the plant disease is sesame bacterial wilt.

[0019] The invention provides application of Pseudomonas paraxanthinosus YC15 strain or bacterial liquid thereof in preparing biocontrol products.

[0020] Preferably, the biocontrol product can be used to control Fusarium pseudograminearum, Fusariumsolani, Colletotrichum fructicola and / or Ralstonia solanacearum pathogens and plant diseases caused by them.

[0021] The present invention also provides a method for preventing and controlling pathogenic fungi / bacteria, or plant diseases caused by them, which comprises treating with the Pseudomonas paraxanthinus YC15 strain or its bacterial liquid; the pathogenic fungi are selected from one or more of Fusarium pseudograminearum, Fusarium solani, and Colletotrichum fructicola; and the pathogenic bacteria are Ralstonia solanacearum.

[0022] Preferably, the bacterial liquid is a fermentation liquid with a concentration of not less than 1×10 8 cfu / mL.

[0023] The present invention has the following beneficial effects:

[0024] The present invention provides a new application of the Pseudomonas paraxanthus YC15 strain in the prevention and control of plant diseases. Studies have shown that the YC15 strain has a broad-spectrum antibacterial activity, has significant inhibitory properties against a variety of plant pathogens, can inhibit pathogenic fungi such as wheat stem rot, sesame root rot, and fruit anthracnose, and has a good inhibitory effect on pathogenic bacteria such as sesame bacterial wilt. The YC15 strain is used in the prevention and control of wheat stem rot. Potted plant experiments show that the treatment with the YC15 strain can reduce plant lesions, break the inhibitory effect of pathogens on plants, inhibit pathogens, promote plant growth, and effectively prevent and control wheat stem rot. The present invention provides a new application of the YC15 strain, which can be used to prevent and control a variety of plant pathogens and their diseases, and has good development and application potential as a biocontrol bacterium. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a graph showing the inhibition of Pseudomonas paraxanthinus YC15 on wheat stem rot pathogen.

[0026] Figure 2 This is a graph showing the inhibition of Pseudomonas paraxanthinus YC15 on sesame root rot pathogens.

[0027] Figure 3 This is a graph showing the inhibition of Pseudomonas paraxanthinum YC15 against fruit anthracnose.

[0028] Figure 4 This is the inhibition rate of Pseudomonas paraxanthin YC15 against fungal diseases.

[0029] Figure 5 This is the inhibition chart of Pseudomonas paraxanthinus YC15 on sesame bacterial wilt pathogen (1:50).

[0030] Figure 6 This is the inhibition chart of Pseudomonas paraxanthin YC15 against sesame bacterial wilt pathogen (1:100).

[0031] Figure 7 This is the inhibition diameter diagram of Pseudomonas paraxanthin YC15 against sesame bacterial wilt pathogen at different concentrations.

[0032] Figure 8 Growth chart of wheat potted plants inoculated and not inoculated with wheat stem rot pathogen.

[0033] Fig. 9 This is a graph of plant height of wheat potted plants inoculated and not inoculated with wheat stem rot pathogen.

[0034] Fig.10 This is a graph showing the seed germination rate of wheat potted plants inoculated and not inoculated with wheat stem rot pathogen. DETAILED DESCRIPTION

[0035] The present invention is further described below in conjunction with the accompanying drawings and specific examples, but the examples do not limit the present invention in any form. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art.

[0036] Unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0037] The Pseudomonas parafulva YC15 strain used in the present invention has been deposited in the Guangdong Microbiological Culture Collection Center (GDMCC) on January 5, 2024, with a deposit number of GDMCC No: 64249, deposited in the Guangdong Microbiological Culture Collection Center, and stored at the 5th Floor, Building 59, No. 100, Xianlie Middle Road, Guangdong Province, and is recorded in the existing patent document: CN117946945A.

[0038] Example 1 Preparation of Pseudomonas paraxanthin YC15 strain fermentation broth

[0039] The Pseudomonas parafulva YC15 strain stored at -80°C was activated, and the activated colonies were picked and placed in LB solid medium (5g yeast extract, 10g tryptone, 10g NaCl, 1000mL water, 17g agar, pH 7.2, sterilized at 121°C for 20min), and cultured at 28°C for 48h. A single colony was picked and placed in LB liquid medium, and shaken at 28°C, 180rpm for 24h to obtain seed liquid.

[0040] According to the volume ratio of Pseudomonas paraflavum YC15 seed liquid to liquid culture medium of 1:100, the YC15 seed liquid was added to LB liquid culture medium (5 g yeast extract, 10 g tryptone, 10 g NaCl, 1000 mL water, pH 7.2, sterilized at 121°C for 20 min), and cultured at 28°C, 180 rpm for 12 h to obtain Pseudomonas paraflavum YC15 fermentation liquid. Among them, the concentration of Pseudomonas paraflavum YC15 was 1-2×10 8 cfu / mL.

[0041] Example 2 Determination of antibacterial effect of Pseudomonas paraxanthin YC15 strain

[0042] (1) Using the four-point confrontation method, indicator bacteria (plant pathogens preserved in the laboratory: wheat stem rot fungus (F. pseudogammalinearum), sesame root rot fungus (F. solani) and fruit anthracnose fungus (C. fructicola)) were beaten into a cake and inoculated in the center of a PDA plate (200 g potato, 20 g glucose, 1 L distilled water, 121°C, high temperature sterilization for 20 min and then poured into the plate), 5 μL of the Pseudomonas paraxanthinum YC15 fermentation liquid prepared in Example 1 was dripped 2.5 cm away from the cake, and an equal amount of ddHO was dripped into the control group. 2 O, set three replicates. Cultivate at 28℃ for a certain period of time until the control grows to 2 / 3 of the plate, observe the antibacterial status and the size of the inhibition circle. Record the colony diameter and calculate the inhibition rate. The calculation formula for the inhibition rate is as follows:

[0043] Inhibition rate = (control colony diameter - treated colony diameter) / control colony diameter × 100%

[0044] The results showed that Pseudomonas paraxanthinus YC15 strain was effective against four plant pathogenic fungi: Triticum aestivum ( Figure 1 ), sesame root rot pathogen ( Figure 2 ), fruit anthracnose ( Figure 3 ) had a good inhibitory effect, and the inhibition rates were 65.62%, 53.08%, and 37.72% ( Figure 4 ), has a broad-spectrum antibacterial activity and can prevent and treat a variety of plant diseases caused by this pathogen.

[0045] (2) The inhibition zone method was used to determine the antibacterial effect of Pseudomonas paraxanthinus YC15 strain on sesame bacterial wilt (Ralstonia solanacearum). The concentration was taken as OD 600 =0.8 sesame bacterial wilt pathogen suspension was evenly spread on LB medium at a concentration of 1:50 and 1:100. After the medium was completely absorbed, 5 μL of YC15 fermentation liquid was added to the center of the culture dish containing sesame bacterial wilt pathogen at a concentration of 1×10 8 cfu / mL, cultured in a constant temperature incubator at 28°C for 24 h, observed the antibacterial effect and measured the diameter of the inhibition zone, and repeated 3 times.

[0046] The experiment showed that the inhibition zone of Pseudomonas paraxanthinus YC15 strain against sesame bacterial wilt was obvious, and the transparent zone at 1:100 concentration ( Figure 6 ) is greater than 1:50 concentration ( Figure 5 ), has a good antibacterial effect, and the statistical results of the diameter of the inhibition zone are as follows Figure 7 As shown, it can be used as a biocontrol bacteria for the prevention and control of sesame bacterial wilt disease.

[0047] Example 3 Control effect of Pseudomonas paraxanthinus YC15 strain fermentation liquid on wheat stem rot

[0048] The efficacy of the fermentation liquid of Pseudomonas paraxanthinus YC15 strain on the control of wheat stem rot was tested by pot experiments. In order to eliminate the potential interference of existing Fusarium species in the soil, especially considering the nature of the sampling sites affected by Fusarium, we conducted two greenhouse experiments using high-pressure sterilized soil. Treatment and control groups were set up. The treatment groups included only YC15 bacterial solution, only wheat stem rot bacteria, and YC15 bacterial solution and wheat stem rot bacteria at the same time. The blank control group was not inoculated with wheat stem rot bacteria, nor was it treated with YC15 bacterial solution. It was only treated with the same amount of clean water. The conidia solution of wheat stem rot bacteria (concentration of 10 5 / mL), YC15 bacterial solution (concentration 1×10 8 cfu / mL), 15 mL was poured at the base of the wheat seedling stem, and 7.5 mL was poured at the base of the wheat seedling stem for the treatment groups inoculated with YC15 solution and wheat stem rot pathogen respectively, while the blank control group was poured with the same volume of clean water. The treatment frequency was 3 days / time, and this experiment was repeated three times independently.

[0049] The results are as follows Figure 8 As shown, plants infected with wheat stem rot bacteria showed obvious symptoms of dwarfing, browning of the stem base, and reduced germination rate; treatment with YC15 bacterial solution alone can promote the growth of wheat seedlings, while wheat seedlings inoculated with wheat stem rot bacteria and YC15 bacterial solution at the same time had significantly reduced lesions and grew better than the bacteria-infected group, eliminating the effect of the bacteria on wheat seedlings and being able to effectively prevent and control wheat stem rot.

[0050] Further statistics on wheat seedling growth parameters, the results are as follows Fig. 9 and Fig.10 As shown, the YC15 bacterial solution treatment can significantly promote the growth of wheat seedlings and increase the germination rate, while the YC15+wheat stem rot pathogen treatment can restore the growth (plant height) of pathogenic wheat seedlings to the normal control level, and its seed germination rate is not significantly different from that of the YC15 bacterial solution treatment group, indicating that the fermentation liquid of Pseudomonas paraxanthin YC15 strain has a good prevention and control effect on wheat stem rot.

[0051] In summary, the present invention provides a new application of Pseudomonas parafulva YC15 strain in the prevention and control of various plant diseases, which can effectively prevent and control wheat stem base rot. Studies have shown that the YC15 strain has a broad-spectrum antibacterial activity and has a good inhibitory effect on a variety of plant pathogens. It can inhibit wheat stem base rot, sesame root rot, fruit anthracnose, and sesame bacterial wilt. When used in the prevention and control of wheat stem rot, it can reduce plant lesions, break the inhibitory effect of pathogens on plants, effectively inhibit pathogens, promote plant growth, and effectively prevent and control wheat stem base rot. The present invention provides a new application of the YC15 strain, which can be used to prevent and control a variety of plant pathogens and their diseases, and has good development and application potential as a biocontrol bacterium.

[0052] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. Use of Pseudomonas parafulva YC15 strain or its bacterial solution in inhibiting plant pathogenic fungi, characterized in that: The plant pathogenic fungi are selected from one or more of Fusarium pseudograminearum, Fusariumsolani and Colletotrichum fructicola.

2. Use of Pseudomonas parafulva YC15 strain or its bacterial solution in preventing and controlling plant diseases caused by plant pathogenic fungi, characterized in that: The plant pathogenic fungi are selected from one or more of Fusariumpseudograminearum, Fusarium solani and Colletotrichum fructicola.

3. The application according to claim 2, characterized in that: The plant diseases are one or more of wheat stem base rot, sesame root rot, and fruit anthracnose.

4. Use of Pseudomonas parafulva YC15 strain or its bacterial solution in inhibiting plant pathogenic bacteria, characterized in that: The plant pathogenic bacterium is Ralstonia solanacearum.

5. Use of Pseudomonas parafulva YC15 strain or its bacterial solution in preventing and controlling plant diseases caused by plant pathogenic bacteria, characterized in that: The plant pathogenic bacterium is Ralstonia solanacearum.

6. The use according to claim 5, characterized in that: The plant disease is sesame bacterial wilt.

7. Use of Pseudomonas parafulva YC15 strain or its bacterial solution in the preparation of biocontrol products, characterized in that: The biocontrol product can be used for preventing and controlling pathogenic bacteria of Fusarium pseudograminearum, Fusariumsolani, Colletotrichum fructicola and / or Ralstonia solanacearum and plant diseases caused by them.

8. A method for preventing and controlling pathogenic fungi / bacteria, or plant diseases caused by them, characterized in that: The treatment is carried out using the Pseudomonas paraxanthinus YC15 strain or its bacterial solution; the pathogenic fungus is selected from one or more of Fusarium pseudograminearum, Fusarium solani, and Colletotrichum fructicola; and the pathogenic bacteria is Ralstonia solanacearum.

9. The use according to any one of claims 1 to 7, or the method according to claim 8, characterized in that: The bacterial liquid is a fermentation liquid, and its concentration is not less than 1×10 8 cfu / mL.

10. The use according to any one of claims 1 to 7, or the method according to claim 8, characterized in that: The Pseudomonas paraxanthinosyltransferase YC15 strain was deposited in the Guangdong Provincial Microbiological Culture Collection Center on January 5, 2024, with the deposit number GDMCC No: 64249.

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