Plant small peptide MG-37 for preventing and treating bacterial blight of rice and application of plant small peptide MG-37
By using the plant peptide MG-37 as an antibacterial agent, the problems of pathogen resistance and environmental pollution in the control of rice bacterial blight were solved, achieving effective pathogen inhibition and environmentally friendly control.
Patent Information
- Application Number
- CN202511328879.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-17
- Publication Date
- 2026-01-20
AI Technical Summary
Existing chemical fungicides pose problems such as pathogen resistance and environmental pollution in the control of rice bacterial blight. There is an urgent need to develop new antibacterial methods that are environmentally friendly and do not easily induce resistance.
Plant peptide MG-37 was used as an antibacterial agent. It was prepared and applied to wounds on rice leaves to inhibit the growth and infection of bacterial blight pathogen PXO99A.
MG-37 significantly inhibits the spread of pathogens at a concentration of 50 μM, causing them to accumulate in the wound area and preventing systemic infection. It is thermally stable and water-soluble, has high safety, and reduces the risk of drug resistance.
Smart Images
Figure CN121362232A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to application research of plant-derived small peptides as bacteriostatic agents in rice against bacterial leaf blight, and belongs to the technical field of biological pesticides. BACKGROUND
[0002] Rice is one of the important staple crops for the global population and is widely planted in Asian regions. With the increase of agricultural planting density and the change of climate conditions, rice is prone to be invaded by various pathogenic microorganisms during the growth process. The bacterial leaf blight of rice is caused by a bacterial pathogen, has a fast transmission speed and high invasion intensity, and can cause rice leaves to wither and the yield to sharply decrease, and has become a key prevention and control problem in the planting management of rice regions in the south.
[0003] The traditional method for preventing and controlling the bacterial leaf blight of rice mainly uses chemical fungicides, but long-term use can cause the following problems: on the one hand, the pathogenic bacteria can gradually form drug resistance through gene mutation, reducing the prevention and control effect; on the other hand, the residues of some fungicides can have a cumulative impact on the ecological environment and increase the interference to the farmland ecological system. Therefore, the agricultural field urgently needs to develop a new type of antibacterial means with safe source, environment-friendly and not easy to induce drug resistance, so as to realize the sustainable prevention and control of the bacterial leaf blight.
[0004] In the research of agricultural biological agents, antibacterial peptides are considered as one of the potential new green agricultural antibacterial agents due to their good biocompatibility and broad-spectrum antibacterial activity. The antibacterial peptide is usually a small molecular polypeptide composed of 20-60 amino acid residues, has the characteristics of positive charge, thermal stability and easy water solubility. Its action mechanism mainly shows that the cell membrane structure of the pathogenic bacteria is destroyed, and then the growth and pathogenic process of the pathogenic bacteria are inhibited. It has been found in research that the antibacterial peptides of different sources show good prospects in the prevention and control of plant diseases, and have obvious advantages in replacing traditional fungicides. SUMMARY
[0005] Therefore, the application provides a new use of a plant small peptide MG-37 in the prevention and control of the bacterial leaf blight of rice, and a bacteriostatic agent preparation and an application method based on the small peptide. The technical problem that the prevention and control of the pathogenic bacteria of the bacterial leaf blight of rice mainly depends on chemical fungicides is solved.
[0006] The purpose of the application can be achieved by the following technical scheme.
[0007] The application of a plant small peptide MG-37 in the prevention and control of the bacterial leaf blight of rice, and the amino acid sequence is shown in SEQ ID NO: 1 (MGSFYWSFSDVAAYCFILLHFIVLRCLILFGFGVAFY).
[0008] The application of a plant small peptide MG-37 in the preparation of a bacteriostatic agent for preventing and controlling the bacterial leaf blight of rice.
[0009] The MG-37 small peptide is used for inhibiting the growth and / or pathogenicity of the rice bacterial blight pathogen PXO99A.
[0010] The bacteriostatic agent contains the plant small peptide MG-37, and the amino acid sequence of the small peptide is shown as SEQ ID NO: 1.
[0011] Preferably, the concentration of the small peptide MG-37 in the bacteriostatic agent is 12.5 μM to 100 μM.
[0012] More preferably, the concentration of the small peptide MG-37 in the bacteriostatic agent is 50 μM.
[0013] A method for preventing and treating rice bacterial blight, comprising applying the bacteriostatic agent to the wound of the rice leaf or the surrounding area to inhibit the expansion and infection of the bacterial blight pathogen PXO99A in the rice tissue.
[0014] Preferably, the application concentration of MG-37 in the method is 12.5 μM to 100 μM.
[0015] Further, the concentration is preferably 50 μM.
[0016] Advantages of the present application:
[0017] The present application is verified by in vitro co-culture experiments and rice plant inoculation models, and it is shown that the small peptide MG-37 can effectively inhibit the growth and migration ability of the pathogen PXO99A at a concentration of 50 μM. It is observed that MG-37 treatment can significantly inhibit the motility of the pathogen in solid culture medium, while in the rice body, the pathogen is aggregated in the wound area after MG-37 treatment, and fails to invade the vascular bundle and cause systemic infection. In the control group, the pathogen can rapidly expand along the vascular bundle, and finally cause significant disease symptoms.
[0018] In addition, MG-37 has a clear source, strong thermal stability and water solubility, and can stably exist in the bacteriostatic agent preparation, which is beneficial to agricultural popularization. As a plant-derived natural product, MG-37 has high safety and environmental friendliness, and is not easy to cause pathogen resistance, thereby providing a new technical direction for constructing a green prevention and control system. BRIEF DESCRIPTION OF DRAWINGS
[0019] Figure 1 A schematic diagram of the influence of the small peptide MG-37 at different concentrations on the aggregation of the bacterial blight pathogen in the present application;
[0020] Figure 2 A schematic diagram of the inhibition of the migration ability of the bacterial blight pathogen by the small peptide MG-37 in the present application;
[0021] Figure 3Figure 1. Inhibition of Xoo infection in rice leaves by small peptide MG-37. Left panel: DMSO treatment, the pathogen (green fluorescence) has spread along the vascular bundle. Right panel: small peptide MG-37 treatment, the pathogen mainly gathered at the wound site and failed to spread to the inside of the vascular bundle.
[0022] Figure 4 Figure 2. Statistical analysis of the length of rice leaves infected by Xoo after treatment with small peptide MG-37. DETAILED DESCRIPTION
[0023] It should be understood that the expression "one or more of" includes individually each of the objects recited after the expression as well as various different combinations of two or more of the recited objects, unless otherwise understood from the context and usage. The expression "and / or" in connection with three or more recited objects should be understood to have the same meaning, unless otherwise understood from the context.
[0024] The use of the terms "including", "has", "have" or "contains", or variations thereof, is intended to cover the meanings as taken in their broadest sense and is not intended to exclude other, not recited elements or steps, unless otherwise specifically stated or understood from the context.
[0025] It should be understood that the order of steps or order for performing certain actions is immaterial so long as the application remains operable. Moreover, two or more steps or actions can be conducted simultaneously.
[0026] The use of any and all examples, or exemplary language herein, is intended merely to better illuminate the application and does not pose a limitation on the scope of the application unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the application.
[0027] Further, the numerical ranges and parameters setting forth the broadest scope of the application are approximations, and are used to encompass the various specific embodiments of the application. Unless otherwise indicated, the numerical ranges and parameters are approximations. It will be apparent to one of ordinary skill in the art that values recited herein can be modified and that variations of the methods described herein can be practiced that are not specifically enumerated, but possess the basic features of the application. All percentages, ratios and proportions herein are by weight, unless otherwise indicated. Same, other specified, or other such similar terms of degree as used herein are intended to allow for a degree of variability in amounts, sizes and other parameters or between techniques and about or around the amounts, sizes and other parameters described herein, for example, due to standard variations in the art, and / or the skill of the individual actually using it. All percentages, ratios and proportions herein are by weight, unless otherwise indicated.
[0028] Example 1. Effect of small peptide MG-37 on the growth characteristics of rice bacterial blight pathogen PXO99A
[0029] Specific steps are as follows: in the clean bench, the PXO99A strain stored at -80°C is inoculated on the surface of NA medium, and is cultured at 28°C for 2-3 days to grow the colonies to a suitable state. After the colonies are formed, the bacterial cells are transferred to a new NA medium using an inoculation loop, and are cultured at 28°C for 3-5 days to obtain single colonies for subsequent inoculation experiments.
[0030] The small peptide MG-37 is dissolved in dimethyl sulfoxide (DMSO) and prepared into a 1 mM stock solution for use. Different concentrations of small peptide MG-37 solution are added to the NA medium to prepare 12.5 μM, 25 μM, 50 μM, and 100 μM small peptide-containing culture solutions, and all the culture solutions are cultured in a 28°C incubator for 10 hours. The control group is an NA medium containing the same concentration of DMSO, and a small peptide flg22 without antibacterial activity is used as a negative control group, and three replicates are set for each group.
[0031] 10 μL of the bacterial solution treated with 50 μM small peptide for 10 hours is added dropwise to 0.3% agarose and 0.7% agarose NA solid medium, respectively, to observe the effect of MG-37 treatment on the motility of the white leaf blight pathogen.
[0032] The results are shown in Figure 1 Under liquid culture conditions, the small peptide MG-37 can promote the aggregation of the white leaf blight pathogen and form obvious flocculent precipitates. It is shown that the small peptide MG-37 can promote the aggregation of the white leaf blight pathogen. Under solid medium conditions, as shown in Figure 2 , the motility of the white leaf blight pathogen is significantly inhibited, showing obvious diffusion limitation. The results show that the small peptide MG-37 significantly inhibits the motility of the white leaf blight pathogen of rice.
[0033] Example 2 Inhibition effect of small peptide MG-37 on the PXO99A-GFP (fluorescently labeled) white leaf blight pathogen of rice
[0034] Specific steps are as follows: in this embodiment, the white leaf blight pathogen PXO99A-GFP is inoculated on NA solid medium and is cultured at 28°C for about 3 days for activation treatment. A well-grown single colony is inoculated into NA liquid medium and is cultured at 28°C and 200 rpm for 12-16 hours until the OD 600 value of the bacterial solution reaches 1.0. Ultra-pure water is used to prepare a 50 μM small peptide MG-37 solution, which is mixed with the above bacterial solution in a proportion to adjust the OD 600 value of the mixed system to 0.5.
[0035] The prepared small peptide MG-37 solution and the same concentration of DMSO control solution were respectively and uniformly applied to the artificial wound area of rice leaves. The treated plants were placed in a culture environment with a temperature of 28°C and a relative humidity of not less than 90% for infection culture for 10 days. On the 2nd day after treatment, the distribution and infection of the pathogen in the rice leaf tissue were observed using a fluorescence microscope. After 10 days of culture, the disease phenotype of the rice was recorded, and the length of the disease spot was measured to evaluate the disease degree.
[0036] As shown in Figure 3 , the small peptide MG-37 can significantly inhibit the spread of the white leaf blight pathogen in rice leaves. On the 2nd day after treatment, the pathogen in the MG-37 group was mainly concentrated in the inoculation site, and no trend of migration along the vascular bundle was observed; while in the control group, the pathogen had begun to spread along the vascular bundle, showing obvious infection and expansion. The disease length measurement results on the 10th day further verified the above observation, as shown in Figure 4 , the disease spot range of the MG-37 treatment group was significantly smaller than that of the control group, indicating that the small peptide MG-37 had a significant inhibitory effect on the infection process of the white leaf blight pathogen.
[0037] The above is only the preferred embodiment of the present application, and it should be noted that for ordinary skilled persons in the art, several improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements should also be considered within the protection scope of the present application.
Claims
1. The use of a plant small peptide MG-37 in the prevention and treatment of rice bacterial leaf blight, characterized in that, The amino acid sequence of the plant small peptide MG-37 is shown as SEQ ID NO:
1.
2. Use of a plant small peptide MG-37 in the preparation of an antibacterial agent for preventing and treating bacterial leaf blight of rice.
3. Use according to claim 1 or 2, characterized in that, The MG-37 is used for inhibiting the growth or pathogenicity of the bacterial leaf blight pathogen PXO99A of rice.
4. A rice bacterial leaf blight inhibitor, characterized by comprising the bacterium of claim 1 or 2. The antibacterial agent contains the plant small peptide MG-37 as claimed in claim 1.
5. The bacterial agent for bacterial leaf blight of rice according to claim 4, characterized by, The concentration of MG-37 in the antibacterial agent is 12.5 μM to 100 μM.
6. The bacterial agent for bacterial leaf blight of rice according to claim 4, characterized by, The concentration of MG-37 in the antibacterial agent is 50 μM.
7. A method for controlling rice bacterial leaf blight, characterized by, The antibacterial agent containing the plant small peptide MG-37 as claimed in claim 1 is applied to the wound or the surrounding area of the rice leaf to inhibit the expansion and infection of the bacterial leaf blight pathogen PXO99A in the rice tissue.
8. The bacterial inhibitor for rice bacterial leaf blight according to claim 7, characterized by, The concentration of the small peptide MG-37 in the antibacterial agent is 12.5 μM to 100 μM.
9. The bacterial inhibitor for rice bacterial leaf blight according to claim 7, characterized by, The concentration of the small peptide MG-37 in the antibacterial agent is 50 μM.