An antibacterial active substance and its application

Abstract

The present invention belongs to the field of agricultural microbiology technology and relates to an antimicrobial active substance and its application. The present invention isolates oleic acid, oosporin, 2,4-dihydroxy-6-benzylformic acid, and dioctyl terephthalate (DTT) from the fermentation product of the fungus Lecanococcus fasciatus. Oleic acid, oosporin, 2,4-dihydroxy-6-benzylformic acid, and DTT have been shown to exhibit good antibacterial activity against wheat stripe rust, Fusarium graminearum, and Fusarium graminearum. These compounds can be used to control wheat stripe rust, plant head blight, and plant stem rot, providing a wider range of compound options for biopesticide development.

Description

Technical Field

[0001] The invention belongs to the technical field of agricultural microorganisms and relates to an antibacterial active substance and application thereof. Background Art

[0002] wheat( Triticum aestivum L.) is the most widely distributed and cultivated cereal crop in the world and is the staple food for 40% of the world's population. However, wheat is susceptible to pathogens throughout its growth and development, especially fungal diseases, which are one of the important factors affecting wheat yield. Among them, wheat stripe rust ( P. striiformis f.sp. Tritici )、Wheat fusarium ( Fusarium headlight ) and wheat stem rot (C rown rot ) is a major disease of wheat, so effective prevention and control of fungal diseases such as wheat stripe rust, wheat fusarium wilt and wheat stem base rot is one of the key means to increase wheat yield.

[0003] At present, the strategy for wheat disease prevention and control mainly relies on disease-resistant breeding and chemical control. Although the use of disease-resistant varieties is the most economical and environmentally friendly measure to prevent and control wheat diseases, due to the frequent virulence mutation of stripe rust, new pathogenic species continue to emerge, resulting in the loss of resistance of wheat disease-resistant varieties. At the same time, the resistance to ergot and stem rot is controlled by multiple genes and is extremely complex. Currently, there are no highly resistant varieties that can be promoted and applied in production. Chemical control is still a powerful tool for plant disease control, but due to excessive reliance on various chemical pesticides, chemical control currently has problems such as high drug resistance, poor durability, pollution to the ecological environment, and chemical pesticide residues causing food safety problems. In addition, for soil-borne diseases, the use of chemical fungicides often cannot effectively kill pathogens in the soil, and it also affects the beneficial microorganisms in the soil.

[0004] Biological control, on the other hand, has become a research hotspot for wheat fungal disease control due to its advantages of environmental friendliness, long-term suppression of pathogens, and abundant and readily exploitable natural resources. The search for microorganisms with antifungal activity and their metabolites is a key approach to fungal disease biological control. However, no reports have been found on antifungal compounds from Lecanococcus fasciatus. Research on these compounds could provide new insights into plant fungal disease control. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention has isolated the fungus Lecanococcus spp. obtained from the laboratory in the early stage and deposited in the China General Microbiological Culture Collection Center with the deposit number CGMCC No. 41682. Lecanicillium aphanocladiiCompounds with antibacterial activity were isolated and purified from GC-2, and the antifungal activity of the screened compounds was further studied, aiming to provide new ideas for the prevention and control of plant fungal diseases such as wheat stripe rust, fusarium head blight, and stem base rot.

[0006] On the one hand, the present invention provides an application of an antimicrobial active substance in inhibiting the growth of plant fungi, wherein the plant fungi are one or more of wheat stripe rust, pseudofusarium graminearum and Fusarium graminearum, and the antimicrobial active substance is one or more of oleic acid, oosporin, 2,4-dihydroxy-6-benzylformic acid and dioctyl terephthalate.

[0007] Furthermore, in the application, the antibacterial active substance is obtained by separating the fermentation broth of Lecanococcus spp., and the preservation number of Lecanococcus spp. is CGMCC No. 41682.

[0008] Furthermore, in the application, when the plant fungus is wheat stripe rust, the concentration of oleic acid is 25 ppm to 100 ppm, the concentration of oosporin is 25 ppm to 100 ppm, the concentration of 2,4-dihydroxy-6-benzylcarboxylic acid is 25 ppm to 100 ppm, and the concentration of dioctyl terephthalate is 25 ppm to 100 ppm.

[0009] Furthermore, in the application, when the plant fungus is Fusarium graminearum or Fusarium graminearum, the concentration of oleic acid is 25 ppm~100 ppm, the concentration of oosporin is 25 ppm~100 ppm, the concentration of 2,4-dihydroxy-6-benzylcarboxylic acid is 25 ppm~100 ppm, and the concentration of dioctyl terephthalate is 5 ppm~50 ppm.

[0010] On the other hand, the present invention also provides an antibacterial active substance for use in preventing and controlling plant fungal diseases induced by wheat stripe rust, pseudofusarium graminearum or Fusarium graminearum, wherein the antibacterial active substance is one or more of oleic acid, oosporin, 2,4-dihydroxy-6-benzylformic acid and dioctyl terephthalate.

[0011] Furthermore, in the application, the antibacterial active substance is obtained by separating the fermentation broth of Lecanococcus spp., and the preservation number of Lecanococcus spp. is CGMCC No. 41682.

[0012] Furthermore, in the application, the plant fungal disease is wheat stripe rust, plant head blight or plant stem base rot.

[0013] Finally, the present invention also provides a method for preventing and controlling plant fungal diseases induced by wheat stripe rust, false Fusarium graminearum or Fusarium graminearum, comprising applying an antibacterial active substance to the plant, wherein the antibacterial active substance is composed of one or more of oleic acid, oosporin, 2,4-dihydroxy-6-benzylcarboxylic acid and dioctyl terephthalate.

[0014] Furthermore, in the method, the plant fungal disease is wheat stripe rust, plant head blight or plant base stem rot.

[0015] Compared with the prior art, the technical solution provided by the present invention has at least the following beneficial effects or advantages:

[0016] The present invention is a strain of Lecanococcus cereus isolated from the laboratory in the early stage and deposited in the China General Microbiological Culture Collection Center with the deposit number CGMCC No. 41682. Lecanicillium aphanocladii Compounds with antibacterial activity were isolated and purified using a GC-2 system: oleic acid, oosporin, 2,4-dihydroxy-6-benzylcarboxylic acid, and dioctyl terephthalate. Microbial assays were further conducted to verify the activity of these antibacterial compounds. The results showed that oleic acid, oosporin, 2,4-dihydroxy-6-benzylcarboxylic acid, and dioctyl terephthalate exhibited excellent antibacterial activity against wheat stripe rust, Fusarium graminearum, and Fusarium graminearum, demonstrating their potential applications in the prevention and control of wheat stripe rust, plant head blight, and stem rot. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The following are the NMR spectra of oleic acid. A is the H NMR spectrum of oleic acid; B is the C NMR spectrum of oleic acid.

[0018] Figure 2 Figure 1 is the NMR spectrum of oosporin. Figure A is the H NMR spectrum of oosporin; Figure B is the C NMR spectrum of oosporin.

[0019] Figure 3 The following are the nuclear magnetic resonance spectra of 2,4-dihydroxy-6-benzylformic acid. A is the hydrogen nuclear magnetic resonance spectrum of 2,4-dihydroxy-6-benzylformic acid; B is the carbon nuclear magnetic resonance spectrum of 2,4-dihydroxy-6-benzylformic acid.

[0020] Figure 4 Figure 1 is the nuclear magnetic resonance spectrum of dioctyl terephthalate. Figure A is the hydrogen nuclear magnetic resonance spectrum of dioctyl terephthalate; Figure B is the carbon nuclear magnetic resonance spectrum of dioctyl terephthalate.

[0021] Figure 5 This is a diagram showing the antibacterial effect of oleic acid on wheat stripe rust.

[0022] Figure 6 This is a diagram showing the antibacterial effect of oosporin on wheat stripe rust.

[0023] Figure 7 This is a diagram showing the antibacterial effect of 2,4-dihydroxy-6-benzylcarboxylic acid on wheat stripe rust.

[0024] Figure 8 This is the antibacterial effect diagram of dioctyl terephthalate on wheat stripe rust.

[0025] Figure 9 This is a diagram showing the antibacterial effect of oleic acid on Fusarium graminearum.

[0026] Figure 10 This is a diagram showing the antibacterial effect of oleic acid on Fusarium graminearum.

[0027] Figure 11 This is a diagram showing the antibacterial effect of oosporin on Fusarium graminearum.

[0028] Figure 12 This is a diagram showing the antibacterial effect of oosporin on Fusarium graminearum.

[0029] Figure 13 This is a diagram showing the antibacterial effect of 2,4-dihydroxy-6-benzylcarboxylic acid on Fusarium graminearum.

[0030] Figure 14 This is a diagram showing the antibacterial effect of 2,4-dihydroxy-6-benzylcarboxylic acid on Fusarium graminearum.

[0031] Figure 15 This is the antibacterial effect diagram of dioctyl phthalate on Fusarium graminearum.

[0032] Figure 16 This is a diagram showing the antibacterial effect of dioctyl phthalate on Fusarium graminearum. DETAILED DESCRIPTION

[0033] The technical solutions of the present invention are described below with reference to the following embodiments; however, the present invention is not limited to the following embodiments.

[0034] In order to enable those skilled in the art to better understand and implement the technical solution of the present invention, the present invention is further described below with reference to specific embodiments and drawings, but the embodiments are not intended to limit the present invention.

[0035] The experimental methods and detection methods described in the following examples are conventional methods unless otherwise specified; the reagents and materials are commercially available unless otherwise specified.

[0036] Example 1

[0037] This example is to prepare the Lecanicillium aphanocladii GC-2 fermentation broth.

[0038] The fungus used in this example is Lecanococcus cereus Lecanicillium aphanocladii GC-2 was isolated and obtained in our laboratory and deposited at the General Microbiology Center of the China Microorganism Culture Collection (CGMCC), Institute of Microbiology, Chinese Academy of Sciences, No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing. The deposit was received by the CGMCC on December 4, 2024; the deposit certificate was issued on January 2, 2025; the deposit number is CGMCC No. 41682. Hereinafter, it will be referred to as Lecanococcus fasciatus CGMCC No. 41682.

[0039] Primary seed preparation:

[0040] Under strictly sterile conditions, spores or mycelium of a slant culture of Lecanopsis fasciculata CGMCC No. 41682 or culture spores or mycelium in a glycerol cryovial or freeze-dried tube was inoculated into a 500 mL baffled Erlenmeyer flask containing 100 mL of seed culture medium. The culture was shaken at 280 rpm at 25-30°C for 5-7 days. Under strictly sterile conditions, samples were taken, stained, and examined under a microscope. If the test results were qualified, a 40% sterile glycerol solution prepared in advance was added at a volume ratio of 1:1, mixed thoroughly, and aliquoted into 2 mL cryovials. The resulting first-grade seeds of Lecanopsis fasciculata CGMCC No. 41682 were prepared.

[0041] The seed culture medium is an agar culture medium, and the agarose culture medium can be any commercially available culture medium of this type. The preparation method of the agar culture medium used in the present invention is as follows: weigh 200 g of potatoes, 20 g of agar, and 20 g of glucose, dissolve them with distilled water, and then dilute to 1000 mL with distilled water, and sterilize at 121°C for 20 min.

[0042] Lecanococcus cereus Lecanicillium aphanocladii Preparation of GC-2 fermentation broth:

[0043] The first-level seeds of the preserved Lecanopsis fasciatus CGMCC No. 41682 were inoculated into a second-level seed culture medium or fermentation medium at a volume percentage of 3-10%, and fermented. The second-level seed culture medium and fermentation medium were the same as the medium used in the first-level seed preparation process, both of which were agar medium. The fermentation conditions were 25-30°C, 280 rpm on a shaker, and cultured for 5-7 days to obtain Lecanopsis fasciatus. Lecanicillium aphanocladii GC-2 fermentation broth.

[0044] Example 2

[0045] This example is the isolation and identification of antimicrobial active substances from Lecanococcus cereus CGMCC No. 41682.

[0046] Fermentation broth pretreatment:

[0047] The Lecanococcus cereus prepared in Example 1 Lecanicillium aphanocladii The GC-2 fermentation liquid was filtered to obtain two parts: fermentation filtrate and mycelium. The fermentation filtrate was reserved for later use.

[0048] Treatment of the fermentation filtrate: The fermentation filtrate was separated and purified by extraction. An equal volume of chloroform was mixed with the fermentation filtrate and stirred thoroughly for 1±0.2 hours. The active substance in the fermentation filtrate was transferred to a solvent. The chloroform phase was then separated and evaporated to dryness under reduced pressure to obtain the antimicrobial active substance of Lecanococcus cereus CGMCC No. 41682.

[0049] The reduced pressure evaporation conditions are: vacuum degree 0.1~0.09MPa, temperature 40~60℃;

[0050] Isolation of antimicrobial active substances from Lecanococcus cereus CGMCC No. 41682:

[0051] The antimicrobial active substance of Lecanococcus cereus CGMCC No. 41682 prepared in the above steps was further separated using a silica gel column layer, and the separation steps were as follows:

[0052] (1) Column wet packing: Use a glass column with a diameter of 10-50 mm and a diameter-to-height ratio of 1:10-30; wet the silica gel with sufficient petroleum ether, stir evenly, and load it into the glass column. Wash the silica gel on the wall with petroleum ether, let it stand for more than 30 minutes, and release the excess solvent for later use;

[0053] (2) Sample preparation: Dissolve the antimicrobial active substance of Lecanococcus cereus CGMCC No. 41682 in dichloromethane, add silica gel at a ratio of dichloromethane to silica gel = 4-5:1 (V / W), stir well, and evaporate the solvent;

[0054] (3) Sample loading: Carefully add the mixture of silica gel and sample to the column, just above the liquid surface;

[0055] (4) Gradient elution: 100% petroleum ether, petroleum ether: ethyl acetate = 100:1, 50:1, 20:1, 10:1, 5:1, 1:1, 100% ethyl acetate, dichloromethane: methanol = 10:1, 5:1, 2:1, 1:1 were used for elution in sequence. The volume of each eluent was 3 to 5 times the volume of the silica gel column. The eluent was collected according to the volume of the silica gel column. The obtained components JQ2, JQ3, JQ4 and JQ10 were identified by nuclear magnetic resonance. The identification results are as follows: Figures 1 to 4 As shown. Figure 1 The results of JQ2 identification, Figure 2 The results of JQ3 identification, Figure 3 The results of JQ4 identification, Figure 4 This is the identification result of JQ10.

[0056] The results showed that JQ2 was oleic acid

[0057] 1 H NMR (400 MHz, CDCl3) δ 5.43 – 5.22 (m, 2H), 2.34 (t, J = 7.5 Hz, 2H),2.01 (dd, J = 12.1, 6.2 Hz, 3H), 1.67 – 1.58 (m, 2H), 1.32 – 1.24 (m, 18H), 0.88 (dd, J = 8.7, 4.9 Hz, 3H); 13 C NMR (101 MHz, CDCl3) δ 180.03, 130.04,129.74, 34.07, 31.93, 29.78, 29.70, 29.61, 29.54, 29.34, 29.16, 29.08, 29.05,27.23, 27.17, 24.68, 22.71, 14.13.

[0058] JQ3 is oosporin

[0059] 1 H NMR (400 MHz, DMSO) δ 11.11 (s, 3H), 1.82 (s, 6H); 13 C NMR (101 MHz, DMSO) δ 113.32, 107.68, 8.07.

[0060] JQ4 is 2,4-dihydroxy-6-benzylcarboxylic acid

[0061] 1 H NMR (400 MHz, DMSO) δ 12.42 (s, 1H), 10.14 (s, 1H), 6.18 (d, J = 2.0Hz, 1H), 6.12 (d, J = 2.3 Hz, 1H), 2.40 (s, 3H); 13 C NMR (101 MHz, DMSO) δ173.73, 164.84, 162.40, 143.47, 111.43, 105.28, 101.02, 23.93.

[0062] JQ10 is dioctyl terephthalate

[0063] 1 H NMR (400 MHz, CDCl3) δ 7.74 – 7.67 (m, 2H), 7.56 – 7.50 (m, 2H), 4.26 – 4.17 (m, 4H), 1.44 – 1.29 (m, 17H), 0.91 (dt, J = 8.8, 6.9 Hz, 13H); 13 CNMR (101 MHz, CDCl3) δ 167.83, 132.46, 131.03, 128.84, 68.19, 38.74, 30.38, 28.96, 23.76, 23.04, 14.12, 11.01.

[0064] Example 3

[0065] This example is an in vitro antibacterial test of oleic acid, oosporin, 2,4-dihydroxy-6-benzylcarboxylic acid and dioctyl terephthalate.

[0066] (1) Test on the antibacterial effect of oleic acid, oosporin, 2,4-dihydroxy-6-benzylcarboxylic acid and dioctyl terephthalate on wheat stripe rust

[0067] The in vitro inhibitory effects of oleic acid, oosporin, 2,4-dihydroxy-6-benzylcarboxylic acid and dioctyl terephthalate on wheat stripe rust were tested according to the spore germination method.

[0068] According to the preliminary test results, oleic acid, 2,4-dihydroxy-6-benzylformic acid and dioctyl terephthalate were dissolved in DMSO and then prepared with Tween-20 to prepare solutions with concentrations of 25 ppm, 50 ppm, 100 ppm and 200 ppm for later use; oosporin was dissolved in DMSO and then prepared with Tween-20 to prepare solutions with concentrations of 5 ppm, 25 ppm, 50 ppm and 100 ppm for later use.

[0069] Place one drop of each concentration of oleic acid, oosporin, 2,4-dihydroxy-6-benzylformic acid, and dioctyl terephthalate on a clean glass slide (use distilled water for control CK). Use an inoculation needle to pick up a small amount of stripe rust summer spores and shake them onto the droplet surface. Turn the glass slide over to make a hanging drop, and place it on a small glass rod covered with soaked absorbent paper at the bottom of a culture dish. Place the culture dish at 10-14°C and check the spore germination after 6-12 hours. Spores that have germinated are considered to be germinated if the length of the germ tube exceeds 50% of the spore diameter. The in vitro inhibitory effects of oleic acid, oosporin, 2,4-dihydroxy-6-benzylformic acid, and dioctyl terephthalate on wheat stripe rust are as follows: Figure 5-Figure 8 As shown, Figure 5 This is the antibacterial effect diagram of oleic acid on wheat stripe rust.

[0070] Figure 6 This is the antibacterial effect diagram of oosporin on wheat stripe rust. Figure 7 This is the antibacterial effect diagram of 2,4-dihydroxy-6-benzylformic acid on wheat stripe rust. Figure 8 Figure 2 shows the inhibitory effect of dioctyl terephthalate on wheat stripe rust. The results show that oleic acid, oosporin, and 2,4-dihydroxy-6-phenylcarboxylic acid all had inhibitory effects on wheat stripe rust within a concentration range of 25 to 100 ppm, with the highest inhibitory effect occurring at 25 ppm. Dioctyl terephthalate also had inhibitory effects on wheat stripe rust within a concentration range of 25 to 100 ppm, with the highest inhibitory effect occurring at 50 ppm.

[0071] (2) Test of the antibacterial effect of oleic acid, oosporin, 2,4-dihydroxy-6-phenylmethylcarboxylic acid and dioctyl terephthalate on the hyphae of Fusarium graminearum and Pseudomonas graminearum

[0072] Fusarium graminearum is the pathogen of plant fusarium wilt, and Pseudofusarium graminearum is the pathogen of plant stem base rot. Fusarium graminearum and Pseudofusarium graminearum are often used in the evaluation of the prevention and control effects of plant fusarium wilt and plant stem base rot. This example evaluates the inhibitory effects of oleic acid, oosporin, 2,4-dihydroxy-6-benzylformic acid and dioctyl terephthalate on Fusarium graminearum and Pseudofusarium graminearum based on the mycelium growth rate method.

[0073] Preparation of compound stock solution: Dissolve oleic acid, oosporin, 2,4-dihydroxy-6-phenylmethylcarboxylic acid and dioctyl terephthalate (DMSO) according to the method of indoor toxicity assay, dilute with Tween-20 to prepare 1×10 4 The mother solution of ppm was stored in a refrigerator at 4℃ for a short period of time.

[0074] Quantitatively add 45 mL of the prepared PDA medium to a 100 mL pre-sterilized, dry Erlenmeyer flask. Add the prepared stock solutions of oleic acid, oosporin, 2,4-dihydroxy-6-benzylformic acid, and dioctyl terephthalate in ascending order, from low to high concentrations, to the final concentrations of the different compounds listed in Table 1. Shake thoroughly and then pour equal amounts into three 9 cm diameter Petri dishes to prepare plates containing the different concentrations of compounds listed in Table 1. A PDA medium plate without compound served as a blank control (CK). Three replicates were performed for each treatment.

[0075] Table 1 Concentration gradients of four compounds

[0076]

[0077] The mycelium growth rate method was used for indoor toxicity tests. According to the preliminary test results, under aseptic operating conditions, activated Fusarium graminearum and Pseudofusarium graminearum were taken, and a sterilized punch was used to punch out a 7 mm diameter cake from the edge of the mycelium with vigorous growth, and inoculated into the center of the prepared plate containing the compound. The plate was sealed with a sealing film and placed in a constant temperature incubator at 25±1°C for dark culture. When the mycelium of the blank control grew to 3 / 4 of the culture dish, the colony diameter was measured by the cross method and compared with the blank control without compound. The inhibition rate of mycelium growth of each fungicide was calculated using the following formula. The recorded data were analyzed using SPSS25.0 software to calculate the toxicity regression equation and EC of different compounds on the mycelium growth of Fusarium graminearum and Pseudofusarium graminearum. 50 Values ​​and correlation coefficients (R 2 The results are shown in Table 2 to Table 5. Figures 9 to 16 shown.

[0078] Growth inhibition rate (%) = [1-(diameter of treated colony-diameter of bacterial cake) / (diameter of control colony-diameter of bacterial cake)] × 100

[0079] Table 2 Test results of the toxicity of oleic acid to Fusarium graminearum and Pseudomonas graminearum hyphae

[0080]

[0081] Table 3 Test results of the toxicity of oosporin to Fusarium graminearum and Pseudomonas graminearum hyphae

[0082]

[0083] Table 4 Toxicity test results of 2,4-dihydroxy-6-benzylcarboxylic acid against Fusarium graminearum and Pseudomonas graminearum hyphae

[0084]

[0085] Table 5 Test results of the toxicity of dioctyl terephthalate to Fusarium graminearum and Pseudomonas graminearum hyphae

[0086]

[0087] Table 2 Figure 9 、 Figure 10 The results showed that the oleic acid concentration in the range of 25~100 ppm had a significant inhibitory effect on the mycelial growth of F. graminearum and F. graminearum, among which the oleic acid concentration of 100 ppm had the best inhibitory effect on the mycelial growth of F. graminearum and F. graminearum.

[0088] Table 3 Figure 11 、 Figure 12The results showed that oosporin had a significant inhibitory effect on the mycelial growth of F. graminearum and F. graminearum when the concentration was in the range of 5-50 ppm, and the best inhibitory effect was achieved when the concentration was 50 ppm.

[0089] Table 4 Figure 13 、 Figure 14 The results showed that 2,4-dihydroxy-6-benzylcarboxylic acid had a significant inhibitory effect on the mycelial growth of Fusarium graminearum and Fusarium graminearum when the concentration was in the range of 25~100 ppm, among which 2,4-dihydroxy-6-benzylcarboxylic acid had the best inhibitory effect on the mycelial growth of Fusarium graminearum and Fusarium graminearum when the concentration was 100 ppm.

[0090] Table 5 Figure 15 、 Figure 16 The results showed that the inhibitory effect of dioctyl terephthalate on the mycelial growth of Fusarium graminearum and Fusarium graminearum was obvious when the concentration of dioctyl terephthalate was in the range of 25~100 ppm, among which the best inhibitory effect on the mycelial growth of Fusarium graminearum and Fusarium graminearum was achieved when the concentration of dioctyl terephthalate was 100 ppm.

[0091] The above results show that oleic acid, oosporin, 2,4-dihydroxy-6-phenylmethylcarboxylic acid and dioctyl terephthalate have strong inhibitory effects on the hyphal growth of Fusarium graminearum and Fusarium graminearum.

[0092] In summary, it can be seen that the antibacterial active substances of the filamentous wax scale fungus CGMCC No. 41682 in the embodiment of the present invention - oleic acid, oosporin, 2,4-dihydroxy-6-benzylcarboxylic acid and dioctyl terephthalate have good activity against wheat stripe rust, Fusarium graminearum and pseudo Fusarium graminearum, and can be used for the prevention and treatment of wheat stripe rust, plant head blight and plant stem rot.

[0093] As described above, the basic principles, main features and advantages of the present invention are well described. The above embodiments and descriptions are merely descriptions of preferred embodiments of the present invention, and the present invention is not limited to the above embodiments. Various changes and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the spirit and scope of the present invention should fall within the scope of protection determined by the present invention.

Claims

1. An application of an antimicrobial active substance in inhibiting the growth of plant fungi, characterized in that: The plant fungus is wheat stripe rust, and the antibacterial active substance is oosporin.

2. The use according to claim 1, characterized in that The antibacterial active substance is from Lecanococcus fasciatus Lecanicillium aphanocladii The fermentation liquid of GC-2 is separated and obtained, and the silk branch Lecanopsis Lecanicillium aphanocladii The deposit number of GC-2 is CGMCC No. 41682.

3. The use according to claim 1, characterized in that The concentration of oosporin is 25ppm~100ppm.

4. Use of an antimicrobial active substance in preventing and treating plant fungal diseases induced by wheat stripe rust, characterized in that: The antibacterial active substance is oosporin.

5. The use according to claim 4, characterized in that The antibacterial active substance is from Lecanococcus fasciatus Lecanicillium aphanocladii The fermentation liquid of GC-2 is separated and obtained, and the silk branch Lecanopsis Lecanicillium aphanocladii The deposit number of GC-2 is CGMCC No. 41682.

6. The use according to claim 5, characterized in that The plant fungal disease is wheat stripe rust.

7. A method for preventing and controlling plant fungal diseases induced by wheat stripe rust, characterized in that: The invention comprises applying an antimicrobial active substance to plants, wherein the antimicrobial active substance is oosporin.

8. The method according to claim 7, characterized in that The plant fungal disease is wheat stripe rust.

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