A method of inhibiting the occurrence of phytophthora root rot in tomato

Abstract

The application discloses a method for inhibiting the occurrence of tomato phytophthora root rot, and relates to the technical field of vegetable disease prevention and treatment, and comprises the following steps: step S1, drying Hericium erinaceus dregs; step S2, mixing the Hericium erinaceus dregs and dry cattle manure to obtain a mixture; step S3, applying the mixture to the farmland soil where tomato seedlings are to be transplanted, and ploughing and mixing uniformly; step S4, transplanting the tomato seedlings into the farmland soil; step S5, soaking the Hericium erinaceus dregs in water to obtain a dregs leaching liquor; and step S6, performing root irrigation with the dregs leaching liquor at multiple times two weeks after the tomato seedlings are transplanted to before flowering. The method uses the residual nutrients in the dregs to supplement the growth requirements of the tomato for various nutrients, improves the growth of the tomato, enhances the resistance of the tomato to pathogenic microorganisms, uses the residual fungi and secretions in the dregs to inhibit the growth of the phytophthora root rot pathogenic bacteria, performs root irrigation with the dregs leaching liquor, supplements the plant nutrition, and inhibits the activity of the pathogenic bacteria.

Description

Technical Field

[0001] This invention belongs to the field of vegetable disease control technology, specifically relating to a method for inhibiting the occurrence of Phytophthora root rot in tomatoes. Technical Background Phytophthora root rot of tomatoes is a common soil-borne disease that can occur from the seedling stage to the mature plant stage. It mainly infects the roots of tomatoes and can cause the entire plant to die in severe cases, seriously threatening tomato production. Phytophthora capsici is one of the main pathogens causing Phytophthora root rot of tomatoes, and this pathogen is a major dominant pathogen shared by economic crops such as tomatoes, peppers, and eggplants.

[0002] Currently, the control of this pathogen mainly relies on chemical control techniques, such as the application of metalaxyl-mancozeb and cymoxanil. While these methods effectively suppress the number of pathogens and reduce the occurrence of tomato root rot, they inevitably bring the risk of soil pollution, affecting the safety and quality of agricultural products and posing safety hazards to humans and animals. In terms of biological control, existing research has found that biocontrol microorganisms are mainly concentrated in the genera *Bacillus*, *Pseudomonas*, and *Streptomyces*. However, the cultivation of these biocontrol microbial agents, their production processes, and production costs make widespread adoption difficult. Therefore, developing an economical, safe, and effective technology to reduce the occurrence of *Phytophthora infestans* root rot in tomatoes has become an urgent problem to be solved in tomato production.

[0003] Hericium erinaceus, a large edible fungus belonging to the Basidiomycetes class, is one of the rare edible and medicinal fungi cultivated in my country. In recent years, the scale of cultivation has expanded rapidly, and the product yield has increased rapidly. However, the proper disposal of the large amount of mushroom residue left after fruiting has become an urgent problem. The mushroom residue still contains a large amount of active Hericium erinaceus mycelium, as well as a variety of unused nutrients from Hericium erinaceus, such as cellulose, lignin, and mineral elements, and many intermediate products from the decomposition of Hericium erinaceus, such as monosaccharides, peptides, and various active substances.

[0004] The large amount of mycelium and its secretions remaining in the Hericium erinaceus (monkey head mushroom) substrate, when introduced into the soil, undoubtedly greatly enhances the soil's biological activity and may also have a certain inhibitory effect on the pathogen of Phytophthora root rot in tomatoes. In addition, other nutrients in the substrate and many intermediate products produced during the growth of Hericium erinaceus may play an important role in improving the rhizosphere microenvironment of tomatoes. Furthermore, the introduction of substrate into the soil increases the soil's organic matter content, strengthens the nutrient supply to tomatoes, and improves the tomatoes' own disease resistance. Combining previous research results, this study attempts to use Hericium erinaceus substrate as the main raw material to explore the inhibition of Phytophthora root rot in tomatoes, which has strong application value. It also solves the negative environmental impact of substrate residue, turning waste into treasure, and has good environmental and economic benefits. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a method for inhibiting the occurrence of Phytophthora root rot in tomatoes. The method involves mixing a small amount of animal manure with the mycelium residue left after harvesting Hericium erinaceus (monkey head mushroom) and incorporating it into the soil tillage layer before transplanting tomato seedlings. Maintaining the soil moisture content at 60-70% of the maximum water holding capacity, two weeks after transplanting and before flowering, the mycelium residue leachate is applied to the plant roots in several applications using a root irrigation method. The mycelium residue, residual Hericium erinaceus mycelium, and subsequent mycelium residue leachate inhibit the reproduction of root rot pathogens, while simultaneously enhancing the absorption of nutrients by the tomato roots and increasing their resistance to pathogens, thereby reducing the occurrence of tomato root rot. This method effectively reduces the incidence of tomato root rot, improving tomato production efficiency and safety.

[0006] To achieve the objectives of this invention, the technical solution is as follows: A method for inhibiting the occurrence of Phytophthora root rot in tomatoes, comprising the following steps: Step S1. Dry the monkey head mushroom residue; Step S2. Provide dried cow dung, mix the dried Hericium erinaceus spore residue from step S1 with the dried cow dung to obtain a mixture; Step S3. Apply the mixture to the farmland soil where the tomato seedlings are to be transplanted, and till and mix it thoroughly. Step S4. Transplant the tomato seedlings into the farmland soil formed in step S3 and water them.

[0007] Preferably, in the method for inhibiting the occurrence of Phytophthora root rot in tomatoes, the raw materials of the Hericium erinaceus mycelium residue in step S1, calculated by mass percentage, include the following components: 60-70% sawdust, 10-15% cottonseed hulls, 15-20% wheat bran, 1% gypsum powder, and 0.5% sugar; the moisture content of the Hericium erinaceus mycelium residue after drying is controlled to be ≤30%; and the sawdust does not contain any volatile aromatic odors.

[0008] Preferably, in the method for inhibiting the occurrence of Phytophthora root rot in tomatoes, the mixture in step S2, by mass percentage, comprises 75-85% Hericium erinaceus mycelium residue and 15-25% dried cow manure.

[0009] Preferably, in the method for inhibiting the occurrence of Phytophthora root rot in tomatoes, the rate at which the mixture is applied to the farmland soil where tomato seedlings are to be transplanted in step S3 is 10.0-15.0 t / hm². 2 The tillage depth is 20-30cm, and the soil moisture content is 60-70% of the field capacity.

[0010] Preferably, in the method for inhibiting the occurrence of Phytophthora root rot in tomatoes, in step S4, the tomato seedlings are 15-20 cm tall when transplanted, the row spacing is 45-55 cm, and the plant spacing is 30-35 cm.

[0011] Preferably, in the method for inhibiting the occurrence of Phytophthora root rot in tomatoes, step S4 further includes the steps of extracting fungal residue leachate and applying the fungal residue leachate to the roots, specifically: Step S5. Soak the Hericium erinaceus residue in water to obtain a leachate. Step S6. Two weeks after transplanting the tomato seedlings until before flowering, use the bacterial residue leachate obtained in step S5 to perform root irrigation multiple times, and then check the plant growth 40 days after transplanting.

[0012] Preferably, in the method for inhibiting the occurrence of Phytophthora root rot in tomatoes, the mass ratio of Hericium erinaceus mycelium residue to water in step S5 is 1:3-5, and the soaking time is 12-24 hours; the water in step S5 is tap water that has been sun-dried for 24-48 hours.

[0013] Preferably, in the method for inhibiting the occurrence of Phytophthora root rot in tomatoes, the number of root irrigations in step S6 is 3-5 times, the amount of mycelium residue leachate used is 150-200 mL / plant each time, and the interval between root irrigations is 7-10 days.

[0014] A method for inhibiting the occurrence of Phytophthora root rot in tomatoes, comprising the following steps: Step a1. Dry the monkey head mushroom residue; Step a2. Soak the monkey head mushroom residue in water to obtain a mushroom residue leachate; Step a3. Transplant the tomato seedlings into farmland soil and water them. Step a4. Two weeks after transplanting the tomato seedlings until before flowering, use the bacterial residue leachate obtained in step a2 for multiple root irrigations, and then check the plant growth 40 days after transplanting.

[0015] Preferably, in the method for inhibiting the occurrence of Phytophthora root rot in tomatoes, in step a1, the moisture content of the dried Hericium erinaceus mycelium residue is controlled to be ≤30%; the sawdust does not contain volatile aromatic odors; in step a2, the mass ratio of Hericium erinaceus mycelium residue to water is 1:3-5, and the soaking time is 12-24h; the water is tap water that has been sun-dried for 24-48h; in step a4, the root irrigation is performed 3-5 times, the amount of mycelium residue leachate used is 150-200 mL / plant each time, and the interval between root irrigations is 7-10 days.

[0016] Compared with existing technologies, the advantages of this invention are: (1) This invention uses the waste mushroom residue produced after the production of Hericium erinaceus as the main raw material. On the one hand, the large amount of nutrients remaining in the mushroom residue can supplement the growth requirements of tomatoes for various nutrients, improve the growth of tomatoes, enhance the resistance of tomatoes to pathogenic microorganisms, improve the living environment of soil microorganisms, and enhance the inhibitory effect of native microorganisms on pathogens. On the other hand, the fungi and their secretions remaining in the mushroom residue can quickly form beneficial bacteria in the roots of tomatoes through the principle of fungal dominance, inhibiting the growth of Phytophthora root rot pathogens. In addition, the root irrigation with mushroom residue leachate can supplement the plant nutrition with amino acids, polysaccharides and other nutrients in the leachate, enhance the root absorption function, and the beneficial microorganisms such as fungi in the leachate can also enhance the rhizosphere effect and inhibit the activity of pathogens.

[0017] (2) The materials used in this invention are safe and reliable, and not only do they not pollute the environment, but they also solve the negative impact of Hericium erinaceus residue on the environment, create a good ecological environment, achieve zero emissions, increase soil organic matter content, and improve soil structure.

[0018] (3) This invention has no special requirements for the environmental conditions for implementation, is suitable for large-scale promotion and application, and has a strong reference value for the prevention and control of pathogenic microorganisms in other horticultural products. Detailed Implementation

[0019] The present invention will be further described below with reference to specific embodiments; in the present invention, unless otherwise specified, all raw materials used in the preparation are commercially available products well known to those skilled in the art.

[0020] Hericium erinaceus (L.) mushroom substrate residue is the waste left after Hericium erinaceus spawn has grown into fruiting bodies. Since Hericium erinaceus culture medium consists of sawdust, cottonseed hulls, wheat bran, corn cobs, etc. as the main materials, plus gypsum powder, quicklime powder, etc., the main substances in the substrate residue are these substances remaining after being absorbed by the Hericium erinaceus mycelium, as well as the parts of the mycelium that were not used to synthesize fruiting bodies after decomposition, such as cellulose, hemicellulose, pectin, polysaccharides, etc. In addition, there are some active ingredients secreted by Hericium erinaceus mycelium, such as amino acids, polysaccharides, lipids and other chemical substances.

[0021] The main microorganisms in Hericium erinaceus spawn are Hericium erinaceus fungi, which exist in the form of mycelium; secondly, there are other cellulose-decomposing and lignin-decomposing bacteria (such as Trichoderma, Penicillium, white-rot fungi, etc.), as well as thermophilic actinomycetes and monosporous fungi present during the fermentation process with cow dung; there are also a large number of bacteria, including aerobic bacteria and anaerobic bacteria (such as Fibromospora and Clostridium).

[0022] After the inoculation of Hericium erinaceus substrate, under the combined action of the original microorganisms in the substrate and soil microorganisms, the polymers (such as cellulose and lignin) and non-lignin substances in the substrate are decomposed into aldehydes, acids, polyphenols, etc., and finally form humus. Humus is the main component of soil organic matter. The increase of soil organic matter is an important indicator of soil fertility improvement and an important carrier for enhancing soil biological activity.

[0023] Hericium erinaceus fungi in the substrate act as the dominant species in the rhizosphere soil of plants, inhibiting the reproduction of pathogens. Secondly, the active substances produced during the production of Hericium erinaceus mycelium, such as chitinase, protease, terpenoids, and lactones, have a certain inhibitory effect on pathogens. In addition, many products of the decomposition of Hericium erinaceus mycelium in the substrate and the organic matter formed by the substrate provide rich nutrients for plant growth and enhance the plant's own disease resistance.

[0024] Example 1 A method for inhibiting the occurrence of Phytophthora root rot in tomatoes, comprising the following steps: Step S1. Dry the Hericium erinaceus residue until the moisture content is ≤30%. The raw materials of Hericium erinaceus residue include the following components by mass percentage: 65% sawdust, 15% cottonseed hulls, 18% wheat bran, 1.5% gypsum powder, and 0.5% sugar. The sawdust does not contain any volatile aromatic odors. Step S2. Provide dried cow dung. Mix the dried Hericium erinaceus residue from Step S1 with the dried cow dung to obtain a mixture comprising 80% Hericium erinaceus residue and 20% dried cow dung. Step S3. Apply the mixture to the farmland soil where tomato seedlings will be transplanted, till and mix thoroughly. The application rate of the mixture to the farmland soil where tomato seedlings will be transplanted is 15.0 t / hm². 2 The tillage depth is 25-30cm, and the soil moisture content is 65% of the field capacity. Step S4. The selected tomato seedling variety is "Su Hong 9," bred by the Vegetable Research Institute of Jiangsu Academy of Agricultural Sciences. In mid-March, tomato seedlings with a height of 15 cm were transplanted into the farmland soil prepared in Step S3. The row spacing was 45 cm, and the plant spacing was 30 cm. 30 seedlings were grouped together, and 3 groups were set up. Using *Phytophthora capsici* as the representative pathogen of *Phytophthora capsici* root rot, a pathogenic fungal solution was prepared by propagation. The final concentration was 1×10⁻⁶. 6The concentration of cuf / ml was administered to the roots of the seedlings 10 days after transplanting, at a rate of 15.0 ml per seedling. All other management was carried out as usual. The disease status of the plants was checked 40 days after transplanting.

[0025] Example 2 A method for inhibiting the occurrence of Phytophthora root rot in tomatoes, comprising the following steps: Step a1. Dry the Hericium erinaceus residue until the moisture content is ≤30%. The raw materials of Hericium erinaceus residue include the following components by mass percentage: 60-70% sawdust, 10-15% cottonseed hulls, 15-20% wheat bran, 1% gypsum powder, and 0.5% sugar. The sawdust does not contain any volatile aromatic odors. Step a2. Select tomato seedlings of the variety "Su Hong 9", bred by the Vegetable Research Institute of Jiangsu Academy of Agricultural Sciences. In mid-March, select tomato seedlings with a height of 15 cm and transplant them into farmland soil without inoculum residue. The row spacing is 45 cm and the plant spacing is 30 cm. 30 plants are divided into 3 groups. Using *Phytophthora capsici* as the representative pathogen of *Phytophthora capsici* root rot, propagate and prepare pathogenic bacterial solution. The final concentration is 1×10⁻⁶. 6 10 days after transplanting, apply 15.0 ml of the solution to the roots of each seedling and manage as usual. Step a3. Soak 5.0 kg of Hericium erinaceus residue in 15 L of tap water that has been dried for 48 hours. The mass ratio of Hericium erinaceus residue to water is 1:3, and the soaking time is 15 hours to obtain a leachate from the residue. Step a4. Transplant tomato seedlings 15, 25 and 35 days after transplanting, and perform root irrigation three times with the fungal residue leachate obtained in step S4. The amount of fungal residue leachate used each time is 150 mL / plant. Check the disease status of the plants 40 days after transplanting.

[0026] Example 3 A method for inhibiting the occurrence of Phytophthora root rot in tomatoes, comprising the following steps: Step S1. Dry the Hericium erinaceus residue until the moisture content is ≤30%. The raw materials of Hericium erinaceus residue include the following components by mass percentage: 65% sawdust, 15% cottonseed hulls, 18% wheat bran, 1.5% gypsum powder, and 0.5% sugar. The sawdust does not contain volatile aromatic substances, such as pine or cypress. Step S2. Provide dried cow dung. Mix the dried Hericium erinaceus residue from Step S1 with the dried cow dung to obtain a mixture comprising 80% Hericium erinaceus residue and 20% dried cow dung. Step S3. Apply the mixture to the farmland soil where tomato seedlings will be transplanted, till and mix thoroughly. The application rate of the mixture to the farmland soil where tomato seedlings will be transplanted is 15.0 t / hm². 2The tillage depth is 25cm, the soil moisture content is 65% of the field maximum water holding capacity, and the soil to be transplanted has not been treated with any biological or chemical substances that affect microbial activity, such as herbicides and fungicides, one month before transplanting. Step S4. The selected tomato seedling variety is "Su Hong 9," bred by the Vegetable Research Institute of Jiangsu Academy of Agricultural Sciences. In mid-March, tomato seedlings with a height of 15 cm were transplanted into the farmland soil prepared in Step S3. The row spacing was 45 cm, and the plant spacing was 30 cm. 30 seedlings were grouped together, and 3 groups were set up. Using *Phytophthora capsici* as the representative pathogen of *Phytophthora capsici* root rot, a pathogenic fungal solution was prepared by propagation. The final concentration was 1×10⁻⁶. 6 10 days after transplanting, administer 15.0 ml of the solution to the roots of each seedling. Other routine management includes watering immediately after transplanting, maintaining a temperature of 25-30℃, avoiding prolonged exposure to strong sunlight, and providing support, tying vines, and pruning as the tomato plants grow.

[0027] Step S5. Soak 5.0 kg of Hericium erinaceus residue in 15 L of tap water that has been dried for 48 hours. The mass ratio of Hericium erinaceus residue to water is 1:3, and the soaking time is 15 hours to obtain a residue leachate. Step S6. Transplant tomato seedlings 15, 25 and 35 days after transplanting, and perform root irrigation three times with the fungal residue leachate obtained in step S5. The amount of fungal residue leachate used each time is 150 mL / plant. Check the plant disease status 40 days after transplanting. Do not apply other chemical or biological pesticides that may affect the activity of microorganisms in the fungal residue and leachate during the root irrigation leachate period.

[0028] Comparative Example 1 Tomato seedlings from the same batch were transplanted into the same soil with a soil moisture content of 65% of maximum water holding capacity, without any bacterial residue or leachate treatment. Ten days after transplanting, the seedlings were treated with 1×10⁻⁶ ppm of 1000 mg / L eggplant. 6 Seedlings treated with a cuf / ml pathogen solution (15.0 mL / plant) as the control group were irrigated with 150 mL / plant / time of clean water at 15, 25 and 35 days after transplanting. At the same time, the disease status of the plants was checked 40 days after transplanting and used as the control. Each group consisted of 30 plants and 3 replicates were set up.

[0029] Reaction Examples Tomato disease severity is graded using a 4-level system, with the following specific standards: Level 0: Healthy and disease-free; Level 1: Root base turns brown, but not soft or rotten, leaves are healthy, and roots have no obvious lesions; Level 2: Root base turns brown and shows obvious constriction, leaf tips or leaves turn yellow, and roots turn brown; Level 3: Root base turns brown and rots, leaves turn yellow, and roots turn brown or even black; Level 4: Roots and root base rot, and the entire seedling dies.

[0030] Disease index = ∑(number of diseased plants × representative value) / total number of plants × representative value of the most severe disease level × 100.

[0031] Prevention efficacy = [(comparative disease index – treatment disease index) / comparative disease index] × 100%.

[0032] The results of Example 1 show that the disease index of the treatment group that was treated with only Hericium erinaceus mycelium residue and dried cow dung as the main raw materials was 21.67±1.67%, while the disease index of Comparative Example 1 was 34.29±2.80%, and the control efficacy was 36.79±1.99%, which showed a significant effect.

[0033] The results of Example 2 showed that in the treatment with only the application of bacterial residue leachate, the plant disease index was 31.11±3.37% and the control efficacy was 9.40±2.59%, which was significantly better than that of Comparative Example 1.

[0034] The results of Example 3 showed that after treatment with fungal residue, dried cow manure and fungal residue leachate, the disease index of the plants was 16.11±1.27%, and the control efficacy was 52.99±1.85%, which was significant.

[0035] The above results show that using Hericium erinaceus mycelium residue as the main raw material, and applying it by mixing it into the soil or by irrigating the roots with the leachate, both methods have a significant inhibitory effect on the occurrence of Phytophthora root rot of tomato, which is caused by Phytophthora capsici. The former has a better inhibitory effect than the latter. The combined application of the two methods has an even better effect.

[0036] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for inhibiting the occurrence of Phytophthora root rot in tomatoes, characterized in that, Includes the following steps: Step S1. Dry the monkey head mushroom residue; Step S2. Provide dried cow dung, mix the dried Hericium erinaceus spore residue from step S1 with the dried cow dung to obtain a mixture; Step S3. Apply the mixture to the farmland soil where the tomato seedlings are to be transplanted, and till and mix it thoroughly. Step S4. Transplant the tomato seedlings into the farmland soil formed in step S3 and water them.

2. The method for inhibiting the occurrence of Phytophthora root rot in tomato according to claim 1, characterized in that, The raw materials for the Hericium erinaceus spore residue in step S1, calculated by mass percentage, include the following components: 60-70% sawdust, 10-15% cottonseed hulls, 15-20% wheat bran, 1% gypsum powder, and 0.5% sugar; the moisture content of the dried Hericium erinaceus spore residue is controlled to be ≤30%; the sawdust does not contain any volatile aromatic odors.

3. The method for inhibiting the occurrence of Phytophthora root rot in tomato according to claim 1, characterized in that, By mass percentage, the mixture in step S2 comprises 75-85% Hericium erinaceus mycelium residue and 15-25% dried cow dung.

4. The method for inhibiting the occurrence of Phytophthora root rot in tomato according to claim 1, characterized in that, In step S3, the mixture is applied to the farmland soil where tomato seedlings are to be transplanted at a rate of 10.0-15.0 t / hm². 2 The tillage depth is 20-30cm, and the soil moisture content is 60-70% of the field capacity.

5. The method for inhibiting the occurrence of Phytophthora root rot in tomato according to claim 1, characterized in that, In step S4, the tomato seedlings should be 15-20cm tall when transplanting, with a row spacing of 45-55cm and a plant spacing of 30-35cm.

6. The method for inhibiting the occurrence of Phytophthora root rot in tomato according to claim 1, characterized in that, Step S4 is followed by the steps of extracting fungal residue leachate and applying the fungal residue leachate to the roots, specifically: Step S5. Soak the Hericium erinaceus residue in water to obtain a leachate. Step S6. Two weeks after transplanting the tomato seedlings until before flowering, use the bacterial residue leachate obtained in step S5 to perform root irrigation multiple times, and then check the plant growth 40 days after transplanting.

7. The method for inhibiting the occurrence of Phytophthora root rot in tomato according to claim 6, characterized in that, In step S5, the mass ratio of Hericium erinaceus spore residue to water is 1:3-5, and the soaking time is 12-24 hours; the water in step S5 is tap water that has been sun-dried for 24-48 hours.

8. The method for inhibiting the occurrence of Phytophthora root rot in tomato according to claim 6, characterized in that, In step S6, root irrigation is performed 3-5 times, with each application of the mycelium residue leachate being 150-200 mL per plant, and the interval between root irrigations being 7-10 days.

9. A method for inhibiting the occurrence of Phytophthora root rot in tomatoes, characterized in that, Includes the following steps: Step a1. Dry the monkey head mushroom residue; Step a2. Soak the monkey head mushroom residue in water to obtain a mushroom residue leachate; Step a3. Transplant the tomato seedlings into farmland soil and water them. Step a4. Two weeks after transplanting the tomato seedlings until before flowering, use the bacterial residue leachate obtained in step a2 for multiple root irrigations, and then check the plant growth 40 days after transplanting.

10. The method for inhibiting the occurrence of Phytophthora root rot in tomato according to claim 9, characterized in that, In step a1, the moisture content of the dried Hericium erinaceus substrate should be ≤30%; the sawdust should not contain any volatile aromatic odors; in step a2, the mass ratio of Hericium erinaceus substrate to water should be 1:3-5, and the soaking time should be 12-24 hours; the water should be tap water that has been sun-dried for 24-48 hours; in step a4, the root irrigation should be performed 3-5 times, and the amount of substrate leachate should be 150-200 mL / plant each time, with an interval of 7-10 days between root irrigations.