A method for preventing and treating tobacco black shank and a medicine

Abstract

The application provides a tobacco black shank disease prevention and treatment method, comprising the following steps: S201, preparing an SMJ solution: mixing a 0.3-0.5 mmol / L potassium sulfite and a 50-100 μmol / L methyl jasmonate mixed solution in a volume ratio of 1:1 to obtain the SMJ solution; S401, root irrigation of tobacco seedlings: when the tobacco seedlings grow to the seventh week, the SMJ solution is used to perform root irrigation on each tobacco seedling once every five days, the application amount of the SMJ solution is 100 mL-200 mL each time, and the root irrigation is performed until the eighth week ends. The tobacco black shank disease prevention and treatment method provided by the application can prevent and treat the tobacco black shank disease without pollution.

Description

Technical Field

[0001] This application relates to the field of tobacco disease control, and in particular to a method and agent for controlling tobacco black shank disease. Background Technology

[0002] Tobacco black shank disease is caused by *Phytophthora nicotianae*, a species belonging to the family Pythaceae. Also known as tobacco blight, it is called black root, black stem rot, or waist rot by tobacco farmers based on its symptom characteristics. *Phytophthora nicotianae* can infect tobacco throughout its entire growth cycle, with the most severe damage occurring in mature plants, primarily affecting the stem base and roots. Typical symptoms of tobacco black shank include wilting, yellowing leaves, stunting, and necrosis of the roots and stem base. The main manifestations include "black shank," "black plaster," and "wearing a large coat" appearance. The average incidence rate is 10%–20%, with severe cases resulting in losses of up to 75% or even total crop failure.

[0003] Currently, the control of tobacco black shank disease has long relied on chemical control. However, the excessive and unscientific use of pesticides will lead to the accumulation of pesticide residues in the tobacco field ecosystem, resulting in a rapid increase in pesticide resistance, increasing the difficulty of control, reducing the quality of tobacco leaves, and in severe cases, affecting the safe production of tobacco, polluting the farmland environment, and disrupting the ecological balance. Summary of the Invention

[0004] To address the aforementioned problems, this application provides a method for the prevention and control of tobacco black shank, which enables pollution-free prevention and control of tobacco black shank.

[0005] To achieve the objectives of this application, the following technical solution is provided:

[0006] In a first aspect, this application provides a method for preventing and treating tobacco black shank disease, comprising:

[0007] S201, Preparation of SMJ solution: Mix 0.3-0.5 mmol / L potassium sulfite solution with 50-100 μmol / L methyl jasmonate solution at a volume ratio of 1:1 to obtain SMJ solution;

[0008] S401, root irrigation of tobacco seedlings: When the tobacco seedlings grow to the seventh week, apply the SMJ solution to each seedling every five days for root irrigation. The amount of SMJ solution applied each time is 100mL-200mL, until the end of the eighth week.

[0009] In one possible implementation, before preparing the SMJ solution, the method further includes: S101, tobacco seedling cultivation: sowing tobacco seeds in nutrient soil and watering with Hogland nutrient solution once a week.

[0010] In one possible implementation, before the step of applying the SMJ solution to each seedling every five days during the seventh week of growth, the method further includes:

[0011] S301, Pre-drenching of tobacco seedlings: On the last day of the third week of tobacco seedling growth, drench each seedling once with 100 mL of the SMJ solution described above.

[0012] In one possible implementation, each liter of the Hogland nutrient solution comprises: 10 mL of A1 solution, 10 mL of A2 solution, 20 mL of B solution, 5 mL of C solution, and 2 mL of iron salt.

[0013] In one possible implementation, the 10 mL A1 solution comprises: 10 mL of 5 mmol / L KNO3.

[0014] In one possible implementation, the 10 mL A2 solution comprises: 10 mL of 5 mmol / L Ca(NO3)2·4H2O.

[0015] In one possible implementation, the 20 mL solution B comprises: 10 mL of 2 mmol / L MgSO4·7H2O and 10 mL of 1 mmol / L KH2PO4.

[0016] In one possible implementation, the 5 mL solution comprises: 1 mL of 0.045 μmol / L H3BO3, 1 mL of 0.01 μmol / L MnCl2·4H2O, 1 mL of 0.8 μmol / L ZnSO4·7H2O, 1 mL of 0.3 μmol / L CuSO4·5H2O, and 1 mL of 0.4 μmol / L Na2MoO4.

[0017] In one possible implementation, the 2 mL iron salt comprises: 1 mL of 0.037 μmol / L FeSO4·7H2O and 1 mL of 0.037 μmol / L EDTA·Na2.

[0018] Secondly, this application also provides a tobacco black shank prevention and treatment agent, comprising: a mixed solution obtained by mixing 0.3-0.5 mmol / L potassium sulfite with 50-100 μmol / L methyl jasmonate in a volume ratio of 1:1.

[0019] Beneficial effects:

[0020] The method for controlling tobacco black shank provided in this application is simple to operate, has low production costs, can quickly and significantly control tobacco black shank, and is pollution-free and harmless. Attached Figure Description

[0021] The accompanying drawings are provided to further understand this application and form part of the specification. They are used together with the embodiments of this application to explain this application and do not constitute a limitation thereof.

[0022] Figure 1 A flowchart of a method for preventing and controlling tobacco black shank provided in an embodiment of this application;

[0023] Figure 2 A detailed flowchart of the tobacco black shank prevention and control method provided in the embodiments of this application;

[0024] Figure 3 The graph shows the effect (disease index) of the tobacco black shank prevention and control method provided in Example 2 of this application;

[0025] Figure 4 This is a comparison diagram showing the effect of using the tobacco black shank prevention and control method provided in Example 2 of this application. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0027] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature; in the description of this application, unless otherwise stated, "multiple" means two or more.

[0028] Example 1

[0029] Figure 1-2 A method for preventing and controlling tobacco black shank disease provided in this application includes:

[0030] S201, Preparation of SMJ solution: Mix 0.3-0.5 mmol / L potassium sulfite solution with 50-100 μmol / L methyl jasmonate solution at a volume ratio of 1:1 to obtain SMJ solution.

[0031] S401, root irrigation of tobacco seedlings: When the tobacco seedlings grow to the seventh week, apply the SMJ solution to each seedling every five days for root irrigation. The amount of SMJ solution applied each time is 100mL-200mL, until the end of the eighth week.

[0032] In one possible implementation, before preparing the SMJ solution, the method further includes: S101, tobacco seedling cultivation: sowing tobacco seeds in nutrient soil and watering with Hogland nutrient solution once a week.

[0033] In one possible implementation, before the step of applying the SMJ solution to each seedling every five days during the seventh week of growth, the method further includes:

[0034] S301, Pre-drenching of tobacco seedlings: On the last day of the third week of tobacco seedling growth, drench each seedling once with 100 mL of the SMJ solution described above.

[0035] In one possible implementation, each liter of the Hogland nutrient solution comprises: 10 mL of A1 solution, 10 mL of A2 solution, 20 mL of B solution, 5 mL of C solution, and 2 mL of iron salt.

[0036] In one possible implementation, the 10 mL A1 solution comprises: 10 mL of 5 mmol / L KNO3.

[0037] In one possible implementation, the 10 mL A2 solution comprises: 10 mL of 5 mmol / L Ca(NO3)2·4H2O.

[0038] In one possible implementation, the 20 mL solution B comprises: 10 mL of 2 mmol / L MgSO4·7H2O and 10 mL of 1 mmol / L KH2PO4.

[0039] In one possible implementation, the 5 mLC solution comprises: 1 mL of 0.045 μmol / L H3BO3, 1 mL of 0.01 μmol / L MnCl2·4H2O, 1 mL of 0.8 μmol / L ZnSO4·7H2O, 1 mL of 0.3 μmol / L CuSO4·5H2O, and 1 mL of 0.4 μmol / L Na2MoO4.

[0040] In one possible implementation, the 2 mL iron salt comprises: 1 mL of 0.037 μmol / L FeSO4·7H2O and 1 mL of 0.037 μmol / L EDTA·Na2.

[0041] Example 2

[0042] Based on the foregoing embodiments, this application also provides a method for preventing and controlling tobacco black shank disease, comprising:

[0043] S101, Seedling Cultivation: Sow Yunyan 87 seeds in nutrient soil and water with Hogland nutrient solution once a week.

[0044] S201, Preparation of SMJ solution: Mix 0.3 mmol / L potassium sulfite solution and 50 μmol / L methyl jasmonate solution at a volume ratio of 1:1 to obtain SMJ solution.

[0045] S301, Pre-drenching of tobacco seedlings: On the last day of the third week of tobacco seedling growth, drench each seedling once with 100 mL of the SMJ solution described above.

[0046] S401, root irrigation of tobacco seedlings: When the tobacco seedlings grow to the seventh week, apply the SMJ solution to each seedling every five days, with each application of 100 mL of SMJ solution, until the end of the eighth week.

[0047] The components of Hogrange nutrient solution are shown in the table below:

[0048]

[0049] The effectiveness of the black shank prevention and control method in this embodiment was tested:

[0050] Preparation of spore suspension:

[0051] The fungal strain of *Phytophthora indicum* (race 1 of *Phytophthora indicum*) was cultured on PDA medium at 28°C for 7 days. Two weeks before inoculation, mycelium was picked and inoculated into the culture medium. The culture was then incubated for two weeks at 28°C with a shaker at 120 rpm, followed by a sudden cooling to prepare a zoospore suspension. The concentration of the zoospore suspension was adjusted to 1×10⁻⁶. 8 cfu / mL, for later use.

[0052] The preparation method of PDA culture medium is as follows:

[0053] (1) Boil 200g of potatoes in 1000mL of distilled water for 10-20 minutes.

[0054] (2) 4 layers of gauze filtration.

[0055] (3) Add 20g of sucrose and stir.

[0056] (4) Add distilled water to 1000 mL.

[0057] (5) Sterilize at 115℃ for 15 minutes.

[0058] Inoculation with black shank bacteria:

[0059] For tobacco seedlings that have grown to 4 weeks old, inoculate the tobacco plants by drenching the roots with spore suspension;

[0060] One method used was stem base wound inoculation: a wound was made at the base of the tobacco seedling stem, 10 mL of zoospore suspension was inoculated into the wound, and the wound was kept moist with absorbent cotton.

[0061] Root irrigation for tobacco seedlings:

[0062] The root irrigation method for tobacco seedlings described in the above embodiments uses SMJ solution and water for root irrigation, respectively.

[0063] Tobacco Black Shank Survey:

[0064] Tobacco black shank disease was graded and investigated according to the national standard "Grading and Survey Methods for Tobacco Diseases and Pests" (GB / T 23222—2008), and the disease index was calculated. Disease index = 100 × ∑(number of diseased plants at each level × representative value at each level) / (total number of plants surveyed × highest level representative value).

[0065] This embodiment demonstrates SMJ root drenching treatment. 20 This embodiment describes a root irrigation treatment with clean water. 70

[0066] As can be clearly seen from the disease index in the table, the disease index of tobacco plants treated with SMJ root irrigation in this embodiment is 20, which is significantly lower than the disease index of 70 for tobacco plants treated with water root irrigation. This indicates that the susceptibility inducer SMJ can significantly improve the resistance of tobacco to black shank and reduce the occurrence of black shank.

[0067] Example 3

[0068] Based on the foregoing embodiments, this application also provides a method for preventing and controlling tobacco black shank disease, comprising:

[0069] S101, tobacco seedling cultivation: Sow tobacco seeds in nutrient soil and water with Hogland nutrient solution once a week.

[0070] S201, Preparation of SMJ solution: Mix 0.4 mmol / L potassium sulfite solution and 75 μmol / L methyl jasmonate solution at a volume ratio of 1:1 to obtain SMJ solution.

[0071] S301, Pre-drenching of tobacco seedlings: On the last day of the third week of tobacco seedling growth, drench each seedling once with 100 mL of the SMJ solution described above.

[0072] S401, root irrigation of tobacco seedlings: When the tobacco seedlings grow to the seventh week, apply the SMJ solution to each seedling every five days, with each application of 150 mL of SMJ solution, until the end of the eighth week.

[0073] The components of Hogrange nutrient solution are shown in the table below:

[0074]

[0075] The effectiveness of the black shank prevention and control method in this embodiment was tested:

[0076] Preparation of spore suspension:

[0077] The fungal strain of *Phytophthora indicum* (race 1 of *Phytophthora indicum*) was cultured on PDA medium at 28°C for 7 days. Two weeks before inoculation, mycelium was picked and inoculated into the culture medium. The culture was then incubated for two weeks at 28°C with a shaker at 120 rpm, followed by a sudden cooling to prepare a zoospore suspension. The concentration of the zoospore suspension was adjusted to 1×10⁻⁶.8 cfu / mL, for later use.

[0078] The preparation method of PDA culture medium is as follows:

[0079] (1) Boil 200g of potatoes in 1000mL of distilled water for 10-20 minutes.

[0080] (2) 4 layers of gauze filtration.

[0081] (3) Add 20g of sucrose and stir.

[0082] (4) Add distilled water to 1000 mL.

[0083] (5) Sterilize at 115℃ for 15 minutes.

[0084] Inoculation with black shank bacteria:

[0085] For tobacco seedlings that have grown to 4 weeks old, inoculate the tobacco plants by drenching the roots with spore suspension;

[0086] One method used was stem base wound inoculation: a wound was made at the base of the tobacco seedling stem, 10 mL of zoospore suspension was inoculated into the wound, and the wound was kept moist with absorbent cotton.

[0087] Root irrigation for tobacco seedlings:

[0088] The root irrigation method for tobacco seedlings described in the above embodiments uses SMJ solution and water for root irrigation, respectively.

[0089] Tobacco Black Shank Survey:

[0090] like Figure 3-4 As shown, tobacco black shank disease was graded and investigated according to the national standard "Grading and Survey Methods for Tobacco Diseases and Pests" (GB / T 23222—2008), and the disease index was calculated. Disease index = 100 × ∑(number of diseased plants at each level × representative value at each level) / (total number of plants surveyed × highest representative value).

[0091] This embodiment demonstrates SMJ root drenching treatment. 10 This embodiment describes a root irrigation treatment with clean water. 70

[0092] As can be clearly seen from the disease index in the table, the disease index of tobacco plants treated with SMJ root irrigation in this embodiment is 10, which is significantly lower than the disease index of tobacco plants treated with plain water root irrigation, which is as high as 70. This indicates that the susceptibility inducer SMJ can significantly improve the resistance of tobacco to black shank and reduce the occurrence of black shank. Furthermore, the higher the concentration of SMJ and the higher the irrigation volume during root irrigation, the lower the disease index of the tobacco plants.

[0093] Example 4

[0094] Based on the foregoing embodiments, this application also provides a method for preventing and controlling tobacco black shank disease, comprising:

[0095] S101, tobacco seedling cultivation: Sow tobacco seeds in nutrient soil and water with Hogland nutrient solution once a week.

[0096] S201, Preparation of SMJ solution: Mix 0.5 mmol / L potassium sulfite solution and 100 μmol / L methyl jasmonate solution at a volume ratio of 1:1 to obtain SMJ solution.

[0097] S301, Pre-drenching of tobacco seedlings: On the last day of the third week of tobacco seedling growth, drench each seedling once with 100 mL of the SMJ solution described above.

[0098] S401, root irrigation of tobacco seedlings: When the tobacco seedlings grow to the seventh week, apply the SMJ solution to each seedling every five days, with each application of 200 mL of SMJ solution, until the end of the eighth week.

[0099] The components of Hogrange nutrient solution are shown in the table below:

[0100]

[0101] The effectiveness of the black shank prevention and control method in this embodiment was tested:

[0102] Preparation of spore suspension:

[0103] The fungal strain of *Phytophthora indicum* (race 1 of *Phytophthora indicum*) was cultured on PDA medium at 28°C for 7 days. Two weeks before inoculation, mycelium was picked and inoculated into the culture medium. The culture was then incubated for two weeks at 28°C with a shaker at 120 rpm, followed by a sudden cooling to prepare a zoospore suspension. The concentration of the zoospore suspension was adjusted to 1×10⁻⁶. 8 cfu / mL, for later use.

[0104] The preparation method of PDA culture medium is as follows:

[0105] (1) Boil 200g of potatoes in 1000mL of distilled water for 10-20 minutes.

[0106] (2) 4 layers of gauze filtration.

[0107] (3) Add 20g of sucrose and stir.

[0108] (4) Add distilled water to 1000 mL.

[0109] (5) Sterilize at 115℃ for 15 minutes.

[0110] Inoculation with black shank bacteria:

[0111] For tobacco seedlings that have grown to 4 weeks old, inoculate the tobacco plants by drenching the roots with spore suspension;

[0112] One method used was stem base wound inoculation: a wound was made at the base of the tobacco seedling stem, 10 mL of zoospore suspension was inoculated into the wound, and the wound was kept moist with absorbent cotton.

[0113] Root irrigation for tobacco seedlings:

[0114] The root irrigation method for tobacco seedlings described in the above embodiments uses SMJ solution and water for root irrigation, respectively.

[0115] Tobacco Black Shank Survey:

[0116] Tobacco black shank disease was graded and investigated according to the national standard "Grading and Survey Methods for Tobacco Diseases and Pests" (GB / T 23222—2008), and the disease index was calculated. Disease index = 100 × ∑(number of diseased plants at each level × representative value at each level) / (total number of plants surveyed × highest level representative value).

[0117] This embodiment demonstrates SMJ root drenching treatment. 5 This embodiment describes a root irrigation treatment with clean water. 70

[0118] As can be clearly seen from the disease index in the table, the disease index of tobacco plants treated with SMJ root irrigation in this embodiment is 5, which is significantly lower than the disease index of tobacco plants treated with plain water root irrigation, which is as high as 70. This indicates that the susceptibility inducer SMJ can significantly improve the resistance of tobacco to black shank and reduce the occurrence of black shank. Furthermore, the higher the concentration of SMJ and the higher the irrigation volume during root irrigation, the lower the disease index of the tobacco plants.

[0119] Example 5

[0120] Based on the foregoing embodiments, this application also provides a tobacco black shank prevention and treatment agent, comprising: a mixed solution obtained by mixing 0.3-0.5 mmol / L potassium sulfite and 50-100 μmol / L methyl jasmonate in a volume ratio of 1:1.

[0121] In the embodiments provided in this application, it should be understood that the disclosed systems, modules, and methods can be implemented in other ways. For example, the module embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, or indirect coupling or communication connection between modules or units, and may be electrical, mechanical, or other forms.

[0122] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit it. This application is not limited to the exact structures described above and illustrated in the accompanying drawings, and it should not be considered that the specific implementation of this application is limited to these descriptions. For those skilled in the art, various changes and modifications made without departing from the concept of this application should be considered to fall within the protection scope of this application.

Claims

1. A method for preventing and controlling tobacco black shank disease, characterized in that, include: S101, tobacco seedling cultivation: sow tobacco seeds in nutrient soil; S201, Preparation of SMJ solution: Mix 0.3-0.5 mmol / L potassium sulfite solution with 50-100 μmol / L methyl jasmonate solution at a volume ratio of 1:1 to obtain SMJ solution; S301, Pre-drenching of tobacco seedlings: On the last day of the third week of tobacco seedling growth, drench each seedling once with 100 mL of the SMJ solution described above. S401, root irrigation of tobacco seedlings: When the tobacco seedlings grow to the seventh week, apply the SMJ solution to each seedling every five days for root irrigation. The amount of SMJ solution applied each time is 100mL-200mL, until the end of the eighth week.

2. The method for preventing and controlling tobacco black shank disease according to claim 1, characterized in that, After sowing the tobacco seeds in the nutrient soil, water them with Hogland nutrient solution once a week; each liter of the Hogland nutrient solution consists of: 10 mL A1 solution, 10 mL A2 solution, 20 mL B solution, 5 mL C solution, and 2 mL iron salt.

3. The method for preventing and controlling tobacco black shank disease according to claim 2, characterized in that, The 10 mL A1 solution comprises: 10 mL of 5 mmol / L KNO3.

4. The method for preventing and controlling tobacco black shank disease according to claim 2, characterized in that, The 10 mL A2 solution comprises: 10 mL of 5 mmol / L Ca(NO3)2·4H2O.

5. The method for preventing and controlling tobacco black shank disease according to claim 2, characterized in that, The 20 mL solution B comprises: 10 mL of 2 mmol / L MgSO4·7H2O and 10 mL of 1 mmol / L KH2PO4.

6. The method for preventing and controlling tobacco black shank according to claim 2, characterized in that, The 5 mL solution comprises: 1 mL of 0.045 μmol / L H3BO3, 1 mL of 0.01 μmol / L MnCl2·4H2O, 1 mL of 0.8 μmol / L ZnSO4·7H2O, 1 mL of 0.3 μmol / L CuSO4·5H2O, and 1 mL of 0.4 μmol / L Na2MoO4.

7. The method for preventing and controlling tobacco black shank disease according to claim 2, characterized in that, The 2 mL iron salt comprises: 1 mL of 0.037 μmol / L FeSO4·7H2O and 1 mL of 0.037 μmol / L EDTA·Na2.

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