Application of coumarin in preventing and treating bacterial wilt of cigar
By applying different concentrations of coumarin solution to cigars, the problem of controlling bacterial wilt in cigars was solved, achieving efficient and environmentally friendly disease control and avoiding the negative effects of chemical pesticides.
Patent Information
- Application Number
- CN202511818634.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-04
- Publication Date
- 2026-03-20
AI Technical Summary
Existing technologies are insufficient to effectively control bacterial wilt in cigars. Chemical pesticides have reduced efficacy and pollute the environment. Soil fumigation is costly. Crop rotation is difficult to implement. The antibacterial effect of existing coumarins on Gram-negative bacteria such as Ralstonia solanacearum is unclear.
Coumarin solutions of varying concentrations, ranging from 20 to 80 mg/L (preferably 80 mg/L), were applied by foliar spraying or root irrigation to control cigar leaf blight.
It significantly reduces the incidence and disease index of bacterial wilt in cigar tobacco, improves the control effect, avoids pollution and soil structure damage caused by chemical pesticides, and is highly efficient and environmentally friendly.
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Figure CN121694318A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of microorganisms, and relates to an application of a resource for preventing and treating cigar tobacco bacterial wilt, in particular to an application of coumarin for preventing and treating cigar tobacco bacterial wilt. BACKGROUND
[0002] Cigar tobacco is a characteristic product with high economic value in the tobacco industry, and its quality formation is closely related to disease prevention and control in the planting process. In recent years, with the continuous expansion of the global cigar tobacco planting scale, soil-borne diseases have become the core bottleneck restricting the high-quality development of the industry, among which the bacterial wilt caused by Ralstonia solanacearum is the most prominent, causing serious economic losses to growers.
[0003] Cigar tobacco bacterial wilt belongs to a typical bacterial soil-borne disease. The pathogen has the characteristics of wide host range and strong survival ability, and can infect more than 200 plant species in more than 30 families of Solanaceae and Leguminosae. It can survive in soil for a long time and has hidden transmission routes, and is difficult to completely eliminate once it occurs. In the main cigar tobacco producing areas of the tropics and subtropics, bacterial wilt occurs commonly, often mixed with root and stem diseases such as black tuber disease, causing wilting of plants, browning of vascular bundles, and eventually death of the whole plant. The disease incidence of serious plots can be more than 80%, and even absolute yield loss can occur. In recent years, with the warming of climate and the change of planting mode, the disease has shown a trend of spreading to temperate tobacco growing areas, and the prevention and control situation is becoming more and more severe.
[0004] At present, the prevention and control measures for cigar tobacco bacterial wilt are still mainly traditional measures, including chemical pesticide spraying, soil fumigation, and crop rotation, etc., but all have significant limitations. Chemical pesticides such as zinc thiazole and quinoline copper have a quick effect in the short term, but have poor targeting, killing pathogenic bacteria while destroying soil microbial community structure, leading to soil micro-ecological disorder and creating favorable conditions for secondary infection of pathogenic bacteria. Long-term use can also make Ralstonia solanacearum develop strong drug resistance, leading to a decrease in prevention and control effect year by year, and pesticide residues directly affect the aroma quality and safety indicators of cigar tobacco. Soil fumigation technology is difficult to popularize in large-scale planting due to high cost and environmental pollution; and crop rotation is difficult to implement in main producing areas due to land resource constraints, and cannot fundamentally solve the disease problem.
[0005] Based on the development needs of "green agriculture" and "reduction of pesticides", the development of biological control technology with high efficiency, safety and environmental friendliness has become a current research hotspot. Coumarin, also known as 1,2-benzopyrone and o-naphtholone, is an organic compound with the chemical formula C9H6O2. Coumarin is an important spice, commonly used as a fixative, deodorant, and prepared as a perfume and spice. It is also used as a flavoring agent for beverages, food, cigarettes, plastic products, rubber products, etc. Although studies have shown that coumarin compounds have certain antibacterial activity, they can reduce the virulence of some pathogenic bacteria by interfering with the formation of bacterial biofilm and inhibiting the synthesis of signaling molecules. For example, coumarin-chalcone conjugates can effectively inhibit the proliferation and invasion of common pathogenic bacteria such as Pseudomonas aeruginosa and Staphylococcus aureus. However, the antibacterial activity of substances has strong specificity. As a special group of highly invasive gram-negative bacteria, Ralstonia solanacearum has a unique lipopolysaccharide component in its cell structure and secreted type III secretion system effector proteins, making it naturally resistant to most antibacterial substances. The antibacterial objects of coumarin reported in existing reports are mainly gram-positive bacteria or ordinary saprophytic bacteria, and do not involve this type of highly pathogenic soil-borne pathogenic bacteria. Therefore, it cannot be predicted that coumarin can inhibit Ralstonia solanacearum and be used to prevent and control tobacco brown rot based on the reported activity of coumarin.
[0006] Although there have been many reports on the application of coumarin in plant protection, its specific application in the prevention and control of tobacco brown rot has not been reported in public literature or patents. The existing technology lacks a specific scheme for applying coumarin to the prevention and control of tobacco brown rot, and does not clearly define the inhibitory effect of coumarin on Ralstonia solanacearum and its mechanism of action. SUMMARY
[0007] The purpose of the present application is to overcome the above-mentioned deficiencies in the prior art and provide the application of coumarin in the prevention and control of tobacco brown rot.
[0008] Another purpose of the present application is to provide a method for preventing and controlling tobacco brown rot with coumarin.
[0009] Still another purpose of the present application is to provide the application of coumarin in the preparation of a reagent for preventing and controlling tobacco brown rot.
[0010] The purpose of the present application can be achieved by the following technical solutions:
[0011] The application of coumarin in the prevention and control of tobacco brown rot.
[0012] Preferably, the method of foliar spraying or root irrigation is used to apply coumarin.
[0013] Preferably, 15 mL of coumarin solution with a concentration of 20-80 mg / L is applied to each tobacco plant.
[0014] Preferably, 15 mL of coumarin solution with a concentration of 40-80 mg / L, preferably 80 mg / L, is applied to each tobacco plant.
[0015] A method for preventing and treating tobacco bacterial wilt by using coumarin, comprising: applying coumarin to tobacco seedlings by foliar spraying or root irrigation after the seedlings are transplanted for 5-7 days.
[0016] Preferably, the tobacco seedlings are tobacco seedlings with four leaves and one heart.
[0017] Preferably, 15 mL of coumarin solution with a concentration of 20-80 mg / L is applied to each tobacco seedling.
[0018] Preferably, 15 mL of coumarin solution with a concentration of 40-80 mg / L, preferably 80 mg / L, is applied to each tobacco plant.
[0019] Application of coumarin in the preparation of a reagent for preventing and treating tobacco bacterial wilt.
[0020] The beneficial effects of the present application are:
[0021] The inventors previously found a stable and high content of organic compound coumarin in tobacco varieties resistant to bacterial wilt based on transcriptome and metabolome data. The present application uses tobacco as the application crop and tobacco bacterial wilt, which is prone to occur in tobacco, as the application object. The effects of different concentrations of coumarin on the prevention and treatment of tobacco bacterial wilt were investigated in detail by foliar spraying and root irrigation. It was found that 15 mL of coumarin solution with a concentration of 20-80 mg / L applied to each tobacco seedling has excellent effects on the prevention and treatment of tobacco bacterial wilt. BRIEF DESCRIPTION OF DRAWINGS
[0022] Figure 1 Effect of foliar spraying of different concentrations of coumarin on the incidence of tobacco bacterial wilt
[0023] Figure 2 Effect of foliar spraying of different concentrations of coumarin on the disease index of tobacco bacterial wilt
[0024] Figure 3 Relative prevention and treatment effect of foliar spraying of different concentrations of coumarin on tobacco bacterial wilt
[0025] Figure 4 Tobacco plant disease situation corresponding to foliar spraying of different concentrations of coumarin (16d)
[0026] Figure 5 Effect of root irrigation of different concentrations of coumarin on the incidence of tobacco bacterial wilt
[0027] Figure 6Effect of coumarin with different concentrations on disease index of cigar tobacco bacterial wilt
[0028] Figure 7 Relative control effect of coumarin with different concentrations on cigar tobacco bacterial wilt
[0029] Figure 8 Disease occurrence of cigar tobacco (16 days) corresponding to root irrigation of coumarin with different concentrations DETAILED DESCRIPTION
[0030] The technical solutions of the present application will be further described below in combination with specific embodiments.
[0031] Example 1: Control effect of foliar spraying of coumarin on cigar tobacco bacterial wilt
[0032] Tested cigar tobacco: De Xue No. 1
[0033] Tested bacterial wilt: R. solanacearum sequence variant 15, strain FJ-SM-SY-2, collected from a bacterial wilt nursery in Fujian, purified by separation, and selected for strong pathogenicity, stored in a -80℃ ultra-low temperature freezer.
[0034] Cigar tobacco seedling raising: Cigar tobacco seeds were soaked in 1‰ silver nitrate (AgNO3) for 12 min and rinsed with sterile water for 5 times. The disinfected cigar tobacco seeds were sowed in a seedling tray and covered with film for seedling raising.
[0035] Cigar tobacco transplanting: After seedling raising for 4-5 true leaves, the cigar tobacco seedlings with consistent growth were transplanted into 9 cm diameter seedling pots, the temperature was controlled at 25-28℃, the humidity was controlled at 55-65% RH (Relative Humidity), and the potting position was randomly changed every two days.
[0036] After 10 days of transplanting, coumarin was applied by foliar spraying, 15 mL per plant. Seven concentrations were set: 1) 2 mg / L coumarin solution; 2) 5 mg / L coumarin solution; 3) 10 mg / L coumarin solution; 4) 20 mg / L coumarin solution; 5) 40 mg / L coumarin solution; 6) 80 mg / L coumarin solution; 7) control group, 15 mL of 0.2% DMSO per plant. Each treatment was set with 3 replicates, and each replicate had 10 cigar seedlings. After one week of transplanting, coumarin was applied by foliar spraying; after two weeks of transplanting, the prepared bacterial suspension was prepared into an OD600nm = 0.005 (about 2x107 cfu / mL) bacterial suspension, and 10 mL of bacterial suspension was inoculated per plant. After inoculation, the tobacco seedlings were cultured in an intelligent artificial climate chamber at a temperature of 30±2℃, a relative humidity of 100%, and a 12 h dark / 12 h light cycle. The indoor disease incidence of tobacco bacterial wilt was divided into five grades: 0, 1, 2, 3, and 4, wherein grade 0 was healthy seedlings; grade 1 was seedlings with mild wilting and wilting degree not exceeding 25%; grade 2 was seedlings with wilting degree exceeding 25% but not exceeding 50%; grade 3 was seedlings with wilting degree exceeding 50% but not exceeding 75%; and grade 4 was seedlings with wilting degree exceeding 75%. The disease incidence was observed and recorded, and the disease incidence rate, disease index, and relative control effect were calculated every 3-4 days. The calculation formula of the relative control effect is as follows:
[0037] The test results are shown in Tables 1, 2, 3, and Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 Compared with the control, foliar spraying of coumarin can reduce the incidence of tobacco bacterial wilt and disease index and improve the relative control effect. At 16 d after inoculation, foliar spraying of 10 mg / L coumarin has the best control effect on bacterial wilt, and there is a significant difference in control effect compared with the control group.
[0038] Table 1 Effect of foliar spraying of different concentrations of coumarin on the incidence of tobacco bacterial wilt
[0039]
[0040] Note: The same column represents a significant difference (P<0.05)
[0041] Table 2 Effect of foliar spraying of different concentrations of coumarin on the disease index of tobacco bacterial wilt
[0042]
[0043] Note: Different lower case letters in the same column represent significant difference (P < 0.05)
[0044] Table 3 Effect of foliar spraying of different concentrations of coumarin on the relative control effect of cigar tobacco bacterial wilt
[0045]
[0046] Note: Different lower case letters in the same column represent significant difference (P < 0.05)
[0047] Example 2 Root irrigation of coumarin for the prevention and treatment effect of cigar tobacco bacterial wilt
[0048] Tested cigar tobacco: De Xue No. 1
[0049] Tested bacterial wilt: Ralstonia solanacearum race 15, strain FJ-SM-SY-2, collected from a bacterial wilt nursery in Fujian, was isolated and purified, and a strong pathogenic strain was selected and stored in a -80°C ultra-low temperature freezer.
[0050] Cigar tobacco seedling: Cigar tobacco seeds were soaked in 1‰ silver nitrate (AgNO3) for 12 min and rinsed with sterile water 5 times. The disinfected cigar tobacco seeds were sown in seedling trays and covered with film for seedling.
[0051] Cigar tobacco transplanting: After 4-5 true leaves, the uniform cigar tobacco seedlings were transplanted into 9 cm diameter seedling pots, the temperature was controlled at 25-28°C, the humidity was controlled at 55-65% RH (Relative Humidity), and the potting position was changed randomly every two days.
[0052] After 10 days of transplanting, coumarin was applied by root irrigation, 15 mL per plant. Seven concentration treatments were set: 1) 2 mg / L coumarin solution; 2) 5 mg / L coumarin solution; 3) 10 mg / L coumarin solution; 4) 20 mg / L coumarin solution; 5) 40 mg / L coumarin solution; 6) 80 mg / L coumarin solution; 7) control group, 15 mL per plant root irrigation with a concentration of 0.2% DMSO. Each treatment was set with 3 replicates, and each replicate had 10 cigar tobacco seedlings. After one week of cigar tobacco seedling transplanting, coumarin was applied by root irrigation; after two weeks of cigar tobacco seedling transplanting, the prepared bacterial suspension was prepared to about OD600nm = 0.005 (about 2 x 10 7The tobacco seedlings were inoculated with 10 mL bacterial suspension per plant. The inoculated tobacco seedlings were placed in an intelligent artificial climate chamber for culture: temperature 30 ± 2°C, relative humidity 100%, 12 h darkness / 12 h light. The indoor disease incidence of tobacco bacterial wilt was divided into five grades: 0, 1, 2, 3, and 4, wherein grade 0 was healthy tobacco seedlings; grade 1 was tobacco seedlings with mild wilting and wilting degree less than 25%; grade 2 was tobacco seedlings with wilting degree more than 25% but less than 50%; grade 3 was tobacco seedlings with wilting degree more than 50% but less than 75%; and grade 4 was tobacco seedlings with wilting degree more than 75%. The disease incidence was observed and recorded, and the disease incidence rate, disease index, and relative control effect were calculated every 3-4 days.
[0053] The test results are shown in Tables 4, 5, 6 and Figure 5 、 Figure 6 、 Figure 7 、 Figure 8 As shown in Tables 4, 5, 6 and
[0054] Table 4 Effect of root irrigation of different concentrations of coumarin on the disease incidence of tobacco bacterial wilt
[0055] Note: The same column represents significant difference (P < 0.05)
[0056] Table 5 Effect of root irrigation of different concentrations of coumarin on the disease index of tobacco bacterial wilt
[0057] Note: The same column represents significant difference (P < 0.05)
[0058] Table 6 Effect of root irrigation of different concentrations of coumarin on the relative control effect of tobacco bacterial wilt
[0059] Note: The same column represents significant difference (P < 0.05).
Claims
1. Application of coumarin in the prevention and control of bacterial wilt in cigar tobacco.
2. The application according to claim 1, characterized in that: Coumarin should be applied by foliar spraying or root irrigation.
3. The application according to claim 1, characterized in that: Apply 15 mL of a coumarin solution with a concentration of 20-80 mg / L to each cigar.
4. The application according to claim 1, characterized in that: Apply 15 mL of a coumarin solution with a concentration of 40-80 mg / L to each cigar, preferably an 80 mg / L coumarin solution.
5. A method for controlling cigar leaf blight with coumarin, characterized in that: include: Five to seven days after transplanting cigar seedlings, apply coumarin by foliar spraying or root irrigation.
6. The method according to claim 5, characterized in that: The cigar seedlings mentioned are cigar seedlings with four leaves and one bud.
7. The method according to claim 5, characterized in that: Each cigar seedling needs to be treated with 15 mL of a coumarin solution with a concentration of 20-80 mg / L.
8. The method according to claim 7, characterized in that: Apply 15 mL of a coumarin solution with a concentration of 40-80 mg / L to each cigar, preferably an 80 mg / L coumarin solution.
9. Application of coumarin in the preparation of reagents for the prevention and control of bacterial wilt in cigar tobacco.
10. The application according to claim 9, characterized in that, The concentration of styrax in the reagent is 40-80 mg / L.