Method for preventing and controlling fusarium oxysporum from infecting plants and application

Abstract

The invention provides a method for preventing and controlling fusarium oxysporum from infecting plants and application, and relates to the technical field of crop disease resistance, and particularly relates to an externally applied compound 2-hydroxy-1, 4-naphthoquinone (Lawsone) or 2-methoxy-1, 4-naphthoquinone (MNQ), which not only significantly inhibits the growth of the fusarium oxysporum, but also greatly alleviates the pathogenic effect of the fusarium oxysporum on the plants, so that the disease resistance of the plants is improved. The application concentration of 2-hydroxy-1, 4-naphthoquinone or 2-methoxy-1, 4-naphthoquinone is 10mM, by adopting the technical scheme, 10mM Lawsone or 10mM MNQ is applied to plants (such as tomatoes) infected by fusarium oxysporum for treatment, the disease resistance of the plants can be remarkably improved, and therefore, the disease resistance of the plants can be remarkably improved. Experimental evidence and theoretical basis are provided for research on prevention and control of Lawsone and MNQ resistant fusarium oxysporum infected plants (such as tomatoes).

Description

Technical Field

[0001] The present invention relates to the technical field of disease resistance of crops, and relates to a method and application for preventing and controlling Fusarium oxysporum infection of plants. Background Art

[0002] tomato( Solanum lycopersicum L.) is an annual herbaceous plant of the Solanaceae family, and is an important crop. Tomatoes are rich in carotene, vitamin C and B vitamins, and have high nutritional value. They can be used as both vegetables and fruits. Fusariumoxysporum Fusarium oxysporum is a type of facultative parasitic fungus that can infect host plants and survive in the soil. The host range of Fusarium oxysporum is very wide, and it can cause more than 100 plant wilts in Solanaceae, Leguminosae, Cucurbitaceae, etc. Fusarium oxysporum is considered to be one of the most destructive pathogens of tomatoes. Infection of tomatoes with Fusarium oxysporum can cause tomato wilt, root rot, fruit rot, etc. Tomato wilt is an important disease of tomatoes and is widely distributed. It occurs in most parts of China. The incidence rate is 15-20%, and in severe cases, all plants die. It is serious in greenhouse tomato production. Tomato wilt is difficult to prevent and control, which can cause great losses in yield and cause huge economic losses to global agricultural production. Therefore, resisting the infection of tomatoes with Fusarium oxysporum can increase tomato yields.

[0003] 2-hydroxy-1,4-naphthoquinone (CAS-No: 83-72-7) (abbreviated as "Lawsone"); 2-methoxy-1,4-naphthoquinone (CAS-No: 2348-82-5) (abbreviated as "MNQ"); There are no reports on the use of these two chemicals in the field of resisting Fusarium oxysporum infection of tomatoes. Summary of the invention

[0004] In order to solve the above problems, the present invention provides an application of Lawsone and MNQ to resist Fusarium oxysporum infection of tomatoes. The present invention provides a theoretical basis for studying the mechanism of Lawsone and MNQ resisting Fusarium oxysporum infection of tomatoes.

[0005] In order to achieve the above object, the present invention provides the following technical solutions: Compared with the prior art, the present invention has the following beneficial effects: The invention provides a method for preventing and controlling Fusarium oxysporum infection of plants, comprising applying a compound 2-hydroxy-1,4-naphthoquinone or 2-methoxy-1,4-naphthoquinone to the plants infected by Fusarium oxysporum.

[0006] Furthermore, the plants are crops.

[0007] Preferably, the plant is tomato.

[0008] Preferably, the plant is a tomato seedling, and the application concentration of the compound 2-hydroxy-1,4-naphthoquinone or 2-methoxy-1,4-naphthoquinone is 10 mM.

[0009] The present invention also provides an application of a compound 2-hydroxy-1,4-naphthoquinone or 2-methoxy-1,4-naphthoquinone in resisting plants from being infected by Fusarium oxysporum.

[0010] Furthermore, the plant is a tomato seedling, and the application concentration of the compound 2-hydroxy-1,4-naphthoquinone or 2-methoxy-1,4-naphthoquinone is 10 mM.

[0011] The present invention provides a fungicide for preventing and controlling infection by Fusarium oxysporum, wherein the active ingredient of the fungicide is a compound 2-hydroxy-1,4-naphthoquinone or 2-methoxy-1,4-naphthoquinone. In some specific embodiments, the fungicide further comprises conventional ingredients known in the prior art such as surfactants, synergists, stabilizers, preservatives, and penetrants.

[0012] Furthermore, the fungicide is used in preventing and controlling Fusarium oxysporum infection in plants.

[0013] Preferably, the plants are crops.

[0014] Preferably, the plant is tomato.

[0015] The present invention has found that Lawsone and MNQ have significant effects on tomato infected by Fusarium oxysporum. The present invention is to inoculate Fusarium oxysporum spores at a concentration of 1×10 6 The results showed that Lawsone and MNQ had the ability to inhibit Fusarium oxysporum by applying them to solid and liquid PDA medium with a concentration of 1 mL / mL. The results showed that Lawsone and MNQ had the ability to resist Fusarium oxysporum infection in tomatoes by inoculating bacterial cakes with a diameter of 1 cm on Micro-Toms grown for one month after pretreatment with methanol, Lawsone and MNQ. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Figure 1: Phenotypic diagram of Fusarium oxysporum cultured in PDA medium containing methanol, 10 mM Lawsone and 10 mM MNQ.

[0017] Figure 2Figure 1: Inhibition zone diagrams made with circular filter paper containing methanol, 10 mM Lawsone and 10 mM MNQ; A is the phenotype diagram of the inhibition zone; B is the statistical diagram of the relative size of the inhibition zone.

[0018] Figure 3 Figure 1: Phenotypic diagram of Fusarium oxysporum cultured in PDA liquid medium containing methanol, 10mM Lawsone and 10mM MNQ.

[0019] Figure 4 Figure 1: Phenotypic graphs and fresh weight and chlorophyll content statistics of tomato leaves inoculated with Fusarium oxysporum after pretreatment with methanol, 10mM Lawsone and 10mM MNQ; A is the phenotype of tomato leaves inoculated with Fusarium oxysporum, without inoculation with Fusarium oxysporum and directly inoculated with Fusarium oxysporum after pretreatment with methanol, 10mM Lawsone and 10mM MNQ; B is the phenotype of tomato inoculated leaves inoculated with Fusarium oxysporum, without inoculation with Fusarium oxysporum and directly inoculated with Fusarium oxysporum after pretreatment with methanol, 10mM Lawsone and 10mM MNQ; C is the fresh weight statistics of tomato inoculated leaves; D is the chlorophyll content statistics of tomato inoculated leaves. DETAILED DESCRIPTION

[0020] To make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme in the present invention is described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work premise belong to the scope of protection of the present invention. Reagents used in the present invention, unless otherwise specified, can all be purchased from the market.

[0021] In one embodiment, the present invention provides a method for resisting infection of tomatoes by Fusarium oxysporum, wherein the compound 2-hydroxy-1,4-naphthoquinone (Lawsone) or 2-methoxy-1,4-naphthoquinone (MNQ) is applied to tomato plants infected by Fusarium oxysporum. In a more specific embodiment, the tomato plants are tomato seedlings, and the application concentration of the compound 2-hydroxy-1,4-naphthoquinone (Lawsone) or 2-methoxy-1,4-naphthoquinone (MNQ) is 10 mM.

[0022] In another embodiment, the present invention provides a fungicide for preventing and controlling infection by Fusarium oxysporum of tomatoes, wherein the active ingredient of the fungicide is the compound 2-hydroxy-1,4-naphthoquinone or 2-methoxy-1,4-naphthoquinone.

[0023] Example 1 Materials and methods 1. Inhibition zone analysis 1. Preparation of Liquid PDA Medium 1.1 Weigh 200g of washed and peeled potatoes, cut them into small pieces, add water and cook until they are soft (boil for 20 to 30 minutes until they can be pierced by a glass rod), and filter them through eight layers of gauze while they are hot.

[0024] 1.2 Add 20g of glucose, stir evenly, and add water to 1000mL after cooling slightly. Divide into different conical bottles, sterilize at 120℃ for 20 minutes, and store after cooling for later use.

[0025] 2. Preparation of solid PDA medium Add 10g agar to the liquid PDA medium, continue heating and stirring to mix, after the agar is dissolved, add 20g glucose, stir evenly, cool slightly and then add water to 1000mL, divide into test tubes or conical flasks, sterilize at 120℃ for 20 minutes, take out the test tubes and tilt them, pour the solid culture medium in the conical flask into the plate, cool and store for later use.

[0026] 3. Inhibition zone experiment 3.1. Inoculate the slant cultured Fusarium oxysporum (Fo) into liquid PDA medium with an inoculation loop, shake at 28°C for 18 h, filter the mycelium with cotton, and count the spores using a hemocytometer until the spore concentration reaches about 1×10 6 / mL.

[0027] 3.2. Cut the sterilized filter paper into circular filter paper pieces with a radius of 1 cm. Add PDA culture medium, 100% methanol, 10 mM Lawsone and 10 mM MNQ on the filter paper pieces respectively in the clean bench and wait for the filter paper pieces to be blown dry.

[0028] 3.3. Take 100 μL of the counted Fusarium oxysporum and spread it evenly on the solid PDA culture medium. Place the filter paper pieces treated with different chemical substances on the four corners of the culture medium respectively. Culture them at 28°C for two days. Take photos after the hyphae grow out.

[0029] 2. Antibacterial test on plate 1.1 Preparation of PDA medium containing different treatments After sterilizing the solid PDA culture medium according to the above steps 2, add equal amounts of methanol, Lawsone, and MNQ to the clean bench, pour into the plate, and cool for later use.

[0030] 1.2 The concentration of spores in 100 μL is about 1×10 6 / mL of spores were evenly spread on the plate, placed in a 28°C incubator for two days, and photographed after mycelium grew out.

[0031] 3. Analysis of antibacterial activity of liquid culture medium 1. Preparation of Liquid PDA Medium 2. In the clean bench, add 3 mL of liquid PDA culture medium to each well of a 12-well plate, and add 300 μL of the prepared 100 mM MNQ stock solution and 100 mM Lawsone stock solution to the well plate to make the final concentration 10 mM. Add 300 μL of methanol solution and 300 μL of PDA liquid culture medium to the control group.

[0032] 3. The concentration of spores in 100 μL is about 1×10 6 / mL of spores were added to a 12-well plate and placed in a 28°C incubator for one week. After mycelium grew out, photos were taken.

[0033] 4. Antibacterial Analysis on Tomatoes 1.MS medium preparation is as shown in Table 1 Sterilize the prepared 1 / 2 MS culture medium with high pressure steam, pour it into a plate in the clean bench, seal it after it cools and solidifies, and place it at 4°C for later use.

[0034] 2. Sterilize the tomatoes with 10% sodium hypochlorite solution in a clean bench for 8 minutes, wash them five times with sterilized pure water, burn the sterilized tweezers in an alcohol lamp, and after cooling, use tweezers to clamp the tomato seeds onto 1 / 2 MS culture medium and culture them for 10 days. When the two cotyledons grow out, move the tomato seedlings to a soil pot with a ratio of nutrient soil: vermiculite: perlite = 3:1:1 to continue growing.

[0035] 3. After the tomato seedlings have grown in the soil pots for three weeks, spray the back of the leaves with 10mM MNQ, 10mM Lawson and methanol respectively. One day after the growth, inoculate the back of the tomato leaves with a 1cm diameter Fusarium oxysporum cake. After one week, observe the growth of the leaves.

[0036] 4. Remove the above tomato leaves, take photos, measure the fresh weight, and then extract chlorophyll to measure the chlorophyll content in each treatment.

[0037] Experimental Results Depend on Figure 1 , Figure 2 and Figure 3 We can see that compared with CK, methanol treatment does not inhibit the growth of Fusarium oxysporum, indicating that methanol, the solvent of MNQ and Lawsone, has no inhibitory effect on Fusarium oxysporum. MNQ and Lawsone have an inhibitory effect on Fusarium oxysporum, and Figure 2From the relative size of the inhibition zone, we can conclude that the antibacterial effect of MNQ is better than that of Lawsone. Figure 4 We can conclude that compared with tomato leaves that were not inoculated with Fusarium oxysporum, tomato leaves inoculated with Fusarium oxysporum will turn yellow and show a wilt phenotype. However, after pre-treatment with MNQ and Lawsone for one day and then inoculated with Fusarium oxysporum, the yellowing phenotype of the leaves was restored, and the leaves of the plants were larger. Methanol treatment did not turn tomato leaves inoculated with Fusarium oxysporum green, which further illustrates the role of MNQ and Lawsone in preventing and controlling Fusarium oxysporum infection of tomato leaves. From the chlorophyll content statistical chart, we can clearly conclude that MNQ and Lawsone treatment can completely restore the yellowing phenotype of leaves after Fusarium oxysporum inoculation.

[0038] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for preventing and controlling Fusarium oxysporum infection in plants, characterized in that: The compounds 2-hydroxy-1,4-naphthoquinone or 2-methoxy-1,4-naphthoquinone were applied to plants infected with Fusarium oxysporum.

2. The method according to claim 1, characterized in that The plants are crop plants.

3. The method according to claim 2, characterized in that The plant is tomato.

4. The method according to any one of claims 1 to 3, characterized in that: The plant is a tomato seedling, and the application concentration of the compound 2-hydroxy-1,4-naphthoquinone or 2-methoxy-1,4-naphthoquinone is 10 mM.

5. Use of the compound 2-hydroxy-1,4-naphthoquinone or 2-methoxy-1,4-naphthoquinone in resisting plants infected by Fusarium oxysporum.

6. The use according to claim 5, characterized in that: The plant is a tomato seedling, and the application concentration of the compound 2-hydroxy-1,4-naphthoquinone or 2-methoxy-1,4-naphthoquinone is 10 mM.

7. A fungicide for preventing and controlling infection by Fusarium oxysporum, characterized in that: The active ingredient of the fungicide is the compound 2-hydroxy-1,4-naphthoquinone or 2-methoxy-1,4-naphthoquinone.

8. Use of the fungicide according to claim 7 in preventing and controlling Fusarium oxysporum infection in plants.

9. The use according to claim 8, characterized in that: The plants are crop plants.

10. The use according to claim 9, characterized in that: The plant is tomato.

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