Foliar fertilizer for improving disease resistance of plants as well as preparation method and application of foliar fertilizer
By mixing mealworm polypeptides with brown algae oligosaccharides to produce foliar fertilizer, the problem of the need for chemical fungicides in existing foliar fertilizers is solved, and the effect of improving plant disease resistance is achieved. In particular, it has shown significant disease control effect and economic benefits in the prevention and control of cucumber downy mildew.
Patent Information
- Application Number
- CN202511538173.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-27
- Publication Date
- 2026-01-20
AI Technical Summary
Existing foliar fertilizers have limited effectiveness in improving plant disease resistance, and need to be used in conjunction with chemical fungicides, which poses risks of drug resistance and biosafety, and are also costly.
A foliar fertilizer was prepared by mixing yellow mealworm polypeptides with brown algae oligosaccharides. The polypeptides with a molecular weight of 3-5 KD were retained through enzymatic hydrolysis and ultrafiltration technology and applied to the leaves to improve plant disease resistance.
It significantly reduces the disease index of cucumber downy mildew, improves plant disease resistance and disease control, and has advantages such as low cost, safety and high efficiency.
Smart Images
Figure SMS_1 
Figure SMS_2
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of disease-resistant fertilizer, in particular to a foliar fertilizer for improving plant disease resistance and a preparation method and application thereof. BACKGROUND
[0002] Foliar fertilizer refers to a type of fertilizer that applies nutrient elements to the surface of crop leaves to play its function through leaf absorption. The foliar fertilization method can prevent nutrient fixation in the soil, has the advantages of supplementing insufficient root fertilization, rapidly supplementing nutrients, fully playing the fertilizer effect, being economical and cost-effective, and reducing soil pollution. Foliar fertilization is often used as an auxiliary measure to supplement and adjust nutrition, but it has unique significance when the root absorption pathway is under external stress and the absorption function is limited.
[0003] At present, research on foliar fertilizer focuses on the improvement of plant yield and quality by new fertilizers (such as seaweed fertilizer and amino acid fertilizer) and special fertilizers (such as trace element compound fertilizer). Research on foliar fertilizer for improving plant disease resistance and reducing disease incidence is still in its infancy. Existing research has found that conventional foliar fertilizer cannot be used alone to control the occurrence and spread of diseases, and still needs to be used in combination with chemical fungicides. This leads to the fact that foliar fertilizer for improving plant disease resistance cannot escape the potential drug resistance and biological safety risks of chemical fungicides.
[0004] Therefore, there is an urgent need to provide a foliar fertilizer of natural origin, high efficiency, low cost, and for improving plant disease resistance and preventing and treating plant diseases. SUMMARY
[0005] The purpose of the present application is to provide a foliar fertilizer for improving plant disease resistance and a preparation method and application thereof to solve the problems existing in the prior art. The foliar fertilizer prepared by the present application can significantly reduce the disease index of cucumber downy mildew, improve the disease resistance of plants, and improve the disease control effect.
[0006] To achieve the above purpose, the present application provides the following solutions:
[0007] The present application provides a preparation method of a foliar fertilizer for improving plant disease resistance, comprising the following steps:
[0008] Take yellow mealworm powder, mix with sodium bicarbonate solution, stand, mix with compound protease preparation, adjust pH, enzymolysis, use ultrafiltration tube to intercept, retain components with a molecular weight greater than 3 KD and less than 5 KD, and obtain yellow mealworm polypeptide.
[0009] Mix the yellow mealworm polypeptide with brown algae oligosaccharide, and obtain the foliar fertilizer.
[0010] Further, the concentration of the sodium bicarbonate solution is 0.1 mmol / L.
[0011] Further, the complex protease preparation is composed of alkaline protease and flavor protease with a mass ratio of 2:1; the total enzyme addition amount of the complex protease preparation is 5000 U / g.
[0012] Further, the enzymolysis time is 3 h, the temperature is 50 DEG C, and the pH is 8.5.
[0013] Further, the mass ratio of the Tenebrio molitor polypeptide to the alginate oligosaccharide is 3:1.
[0014] The application further provides a foliar fertilizer obtained by the preparation method.
[0015] The application further provides application of the foliar fertilizer in improving plant disease resistance.
[0016] The application further provides application of the foliar fertilizer in preventing and treating cucumber downy mildew.
[0017] The application further provides a method for improving plant disease resistance, comprising the step of applying the foliar fertilizer to leaves of the plant.
[0018] The application further provides a method for preventing and treating cucumber downy mildew, comprising the step of applying the foliar fertilizer to leaves of the cucumber.
[0019] The application discloses the following technical effects:
[0020] The application uses alkaline protease and flavor protease to perform enzymolysis on Tenebrio molitor powder pretreated by a sodium bicarbonate solution, retains Tenebrio molitor polypeptide with a molecular weight of 3-5 KD through ultrafiltration, mixes the Tenebrio molitor polypeptide with alginate oligosaccharide, and prepares a foliar fertilizer. Experimental results show that application of the foliar fertilizer prepared by the application can significantly reduce a disease index of cucumber downy mildew, improve plant disease resistance, and improve disease prevention and control effects. The application provides a new foliar fertilizer for crop disease prevention and control, and has advantages of low cost, simple preparation, safety, high efficiency, and the like. The application has significant agricultural economic value and wide application prospect. DETAILED DESCRIPTION
[0021] The various exemplary embodiments of the application will now be described in detail, which should not be considered as limiting the application, but should be understood as a more detailed description of certain aspects, characteristics and embodiments of the application.
[0022] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. Additionally, for a range of values of, for example, the upper limit of the range and the lower limit of the range are each implicitly disclosed. Each intermediate value of is included in the present application. The upper and lower limits of these smaller ranges can independently be included or excluded in the range.
[0023] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Although preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application. All documents mentioned herein are incorporated by reference to disclose and describe in further detail the methods and / or materials associated with the documents. In the event of conflict between the present specification and any incorporated document, the present specification controls.
[0024] Many modifications and variations of the present application described in the specific embodiments of the application can be made by those skilled in the art without departing from the spirit or scope of the application. Other implementations of the application will be apparent to those skilled in the art from consideration of the specification and practice of the application. The specification and examples are illustrative only.
[0025] As used herein, the terms "comprises", "comprising", "includes", "including", "has", "having", "contains", "containing", or variations thereof, are intended to be open-ended terms that mean including, but not limited to.
[0026] The prior art alternative technical solutions for applying plant foliage fertilizer to improve plant disease resistance include: amino acid selenium foliage fertilizer improves the resistance of apple fruit to ring rot. With "Changfu No. 2" apple in fruiting period as test material, the incidence of apple fruit ring rot was investigated and the related resistance enzyme activity of the fruit was determined by continuous field spraying of amino acid selenium foliage fertilizer, and the prevention and control effect of amino acid selenium foliage fertilizer on apple ring rot was determined. Among them, the amino acid selenium foliage fertilizer is "Selenium Shibaobao" foliage fertilizer, which is developed by the Institute of Pomology, Chinese Academy of Agricultural Sciences, and the fungicide is 70% thiophanate-methyl wettable powder (WP) produced by Japan Soda Corporation; the application method is amino acid selenium 500 times dilution + 70% thiophanate-methyl WP 700 mg / kg.
[0027] The prior art on the application of plant foliage fertilizer to improve plant disease resistance includes: application of a new type of foliage fertilizer for prevention and treatment of pepper virus disease. The prevention and treatment effects of 2% aminosugar oligosaccharide aqueous solution and foliage fertilizer prepared therefrom on pepper virus disease are studied through efficacy test. Aminosugar oligosaccharide is a product of Shandong Qingdao Bozhihui Li Biological Technology Co., Ltd.; and 2% aminosugar oligosaccharide aqueous solution foliage fertilizer is a product of Jinzhengda Ecological Engineering Group Co., Ltd. The test is carried out in a greenhouse of Jinzhengda Ecological Engineering Group Co., Ltd. in Linshu County, Shandong Province. Potted plants are used, and 4 treatments are set: T1 is a water control (CK); T2 is 20% virus A soluble powder; T3 is aminosugar oligosaccharide aqueous solution; and T4 is aminosugar oligosaccharide aqueous solution foliage fertilizer. Each treatment has 3 replicates. Each pot (volume 4dm 3 ) contains 10 kg of soil, which is mixed uniformly and then equally divided into pots. Uniform pepper seedlings are transplanted into the pots, and then an equal amount of water is poured. The test is carried out when the seedlings recover and grow to 8 leaves. No other pesticides for preventing and treating other diseases and pests are used during the test.
[0028] The prior art on the application of plant foliage fertilizer to improve plant disease resistance includes: influence of 5 kinds of foliage fertilizers on growth and development of ginseng and research on prevention and treatment of ginseng stem blight. Alginic acid aqueous foliage fertilizer (Germany Conpak Company); alginin (Shandong Jingpu Biological Technology Co., Ltd.); Tianda 2116 medicine special (Shandong Tianda Biological Pharmaceutical Co., Ltd.); Zhixin high magnesium (American Plekang Company); and potassium dihydrogen phosphate (Jinzhengda Group). Two-year-old ginseng with spores is selected, with a row spacing of 15 cm and a plant spacing of 3 cm-5 cm, about 200 plants per 1m 2 , with uniform soil, 6 treatments and 3 replicates, each plot area of 2m 2 , a total of 36m 2 . The soil organic matter content is 138.04 g / kg, the available potassium content is 171.15 mg / kg, the alkali-hydrolyzable nitrogen content is 24.14 mg / kg, and the pH is 5.22. The field test adopts a random block arrangement, and the foliage fertilizer is sprayed on July 3, 2016, then sprayed once every 7 days, a total of 3 times. After the treatment is completed, samples are taken on September 7, and the agronomic traits of ginseng are investigated, including chlorophyll, plant height, root length, root diameter, single root dry weight, dry matter content, determination of ginseng nutrient elements by ICP-EOS, and investigation of the incidence of leaf surface of the aboveground part of 20 randomly selected ginseng seedlings per plot, and the area of each plant leaf infected is classified.
[0029] Existing technologies for applying foliar fertilizers to improve plant disease resistance include: the effects of different types of foliar fertilizers on the agronomic traits and disease resistance of flue-cured tobacco. Using the flue-cured tobacco variety Yunyan 97 as the research material, field trials were conducted to study the effects of different types of foliar fertilizers on the agronomic traits, resistance to mosaic virus, resistance to red spot disease, resistance to climate spot disease, and resistance to black shank disease of flue-cured tobacco. The experiment set up 7 treatments: Treatment (1) was Stecoop (75g / hm) 2 Treatment (2) was Vigo No. 7 (225g / hm). 2 Treatment (3) was silicon fertilizer (225g / hm). 2 Treatment (4) was ammonium molybdate (225 g / hm). 2 ); Treatment (5) is for copper master + master brother (300g / hm) 2 Treatment (6) was a live source library (1500 mL / hm). 2 Treatment (7) was a water control; randomized block design was adopted in the plots, with 3 replicates. All tobacco seedlings were transplanted on April 25, with a row spacing of 110cm × 55cm. 35, 45, and 55 days after transplanting, nutrient element solutions of the corresponding concentrations were sprayed evenly. Other cultivation and management measures were in accordance with the management of high-quality flue-cured tobacco leaves in the field. Among them, the amount of pure nitrogen applied was 10. 5 kg / hm 2 The nitrogen, phosphorus, and potassium ratio was 8:12:25. During tobacco growth, investigations were conducted on diseases such as mosaic virus, red spot, climate spot, and black shank. Disease investigations were carried out according to the national standard GB / 23222-2008 "Classification and Investigation Methods for Tobacco Diseases and Pests," using a 5-point sampling method, with 10 plants surveyed at each point. Depending on the specific disease, investigations began at the early stage of disease onset, with investigations conducted every 7-10 days for at least 4 consecutive investigations (3 investigations for black shank). The incidence and disease index of each disease were calculated.
[0030] Existing technologies for applying foliar fertilizers to improve plant disease resistance include: a microbial fungicide and microbial fertilizer / foliar fertilizer for controlling plant diseases; and a microbial fungicide whose effective ingredient is a compound of microbial active ingredients and chemical active ingredients; wherein the preparation method of the microbial active ingredients is as follows: *Phellinus cereus* GXMS1 is picked and inoculated onto PDA solid medium and cultured at 25℃ for 3 days; 10 mycelial cakes with a diameter of 5 mm are punched at the edge of the colony and inoculated into an Erlenmeyer flask containing 150 mL of PDA liquid medium; after culturing at 25℃ and 150 r / min for 7 days, the culture is filtered through double-layer gauze, and the bacterial count in the culture medium is adjusted to 8.0 × 10⁻⁶ using PDA liquid medium. 6cfu / g, the microbial active ingredient is obtained; the chemical active ingredient is fluopyram or flusilazole. When the chemical active ingredient is fluopyram, the mass ratio of the microbial active ingredient to the chemical active ingredient is (1-16):(8-1). When the chemical active ingredient is flusilazole, the mass ratio of the microbial active ingredient to the chemical active ingredient is (1-25):(10-1). The application of the microbial fungicide in the prevention and control of plant diseases. The plant diseases include apple ring rot, tomato gray mold, pepper anthracnose, cucumber powdery mildew, rice bunt, pea root rot and wheat scab. A microbial fertilizer or microbial foliar fertilizer is prepared from the following components: 0.75-20% of the microbial fungicide, 8-15% of humic acid, 0.1-0.2% of sodium selenite, 20-30% of fertilizer components, 1-10% of wetting agent, 2-10% of dispersing agent, and the balance of fillers. The fertilizer components are selected from one or more combinations of zinc sulfate, sodium selenite, ammonium sulfate, potassium dihydrogen phosphate, potassium nitrate, sodium octaborate tetrahydrate, urea, ammonium chloride, manganese sulfate, potassium silicate and sodium carbonate. The wetting agent is soapnut powder; the dispersing agent is sodium lignosulfonate; and the fillers are attapulgite.
[0031] Example 1. Preparation method of Tenebrio molitor polypeptide
[0032] The alkaline protease and flavor protease were taken respectively, and a compound protease preparation with a total enzyme amount of 5000 U / g was prepared according to a mass ratio of 2:1.
[0033] Tenebrio molitor powder 10 g was mixed with 0.1 mmol / L sodium bicarbonate solution 100 mL, and then was placed for 3 h. Then, the compound protease preparation was added, and the enzyme hydrolysis was carried out at 50°C and pH=8.5 for 3 h. Then, the temperature was increased to 90°C, and the enzyme was inactivated by heating for 10 min. The enzyme hydrolysate with a molecular weight greater than 3 KD and less than 5 KD was retained by using an ultrafiltration tube, and then Tenebrio molitor polypeptide was obtained.
[0034] Example 2. Preparation method of a foliar fertilizer
[0035] Tenebrio molitor polypeptide 4 g prepared in Example 1 was mixed with 1 g of brown algal oligosaccharide, and then a foliar fertilizer was obtained.
[0036] Example 3. Preparation method of a foliar fertilizer
[0037] Tenebrio molitor polypeptide 2 g prepared in Example 1 was mixed with 1 g of brown algal oligosaccharide, and then a foliar fertilizer was obtained.
[0038] Example 4. Preparation method of a foliar fertilizer
[0039] Tenebrio molitor polypeptide 8 g prepared in Example 1 was mixed with 1 g of brown algal oligosaccharide, and then a foliar fertilizer was obtained.
[0040] Example 5. Preparation method of a foliar fertilizer
[0041] Take the yellow mealworm polypeptide prepared in Example 1 6 g, mix with 1 g of alginate oligosaccharide, and you get a foliar fertilizer.
[0042] Example 6 A method for preparing a foliar fertilizer
[0043] Take the yellow mealworm polypeptide prepared in Example 1 3 g, mix with 1 g of alginate oligosaccharide, and you get a foliar fertilizer.
[0044] Example 7 A method for preparing a foliar fertilizer
[0045] Take the yellow mealworm polypeptide prepared in Example 1 5 g, mix with 1 g of alginate oligosaccharide, and you get a foliar fertilizer.
[0046] Example 8 A method for preparing a foliar fertilizer
[0047] Take the yellow mealworm polypeptide prepared in Example 1 7 g, mix with 1 g of alginate oligosaccharide, and you get a foliar fertilizer.
[0048] Comparative Example 1
[0049] Take 10 g of yellow mealworm powder and mix with 100 mL of 0.1 mmol / L sodium bicarbonate solution, stand at room temperature for 3 h, add 5000 U / g of total enzyme amount of alkaline protease, 50℃, pH=8.5, enzymolysis for 3 h, heat to 90℃, heat for 10 min to inactivate the enzyme; use an ultrafiltration tube to retain the enzymolysis product with a molecular weight greater than 3 KD and less than 5 KD, and you get a yellow mealworm polypeptide.
[0050] Take the yellow mealworm polypeptide prepared above 6 g, mix with 1 g of alginate oligosaccharide, and you get a foliar fertilizer.
[0051] Comparative Example 2
[0052] Take 10 g of yellow mealworm powder and mix with 100 mL of 0.1 mmol / L sodium bicarbonate solution, stand at room temperature for 3 h, add 5000 U / g of total enzyme amount of flavor protease, 50℃, pH=8.5, enzymolysis for 3 h, heat to 90℃, heat for 10 min to inactivate the enzyme; use an ultrafiltration tube to retain the enzymolysis product with a molecular weight greater than 3 KD and less than 5 KD, and you get a yellow mealworm polypeptide.
[0053] Take the yellow mealworm polypeptide prepared above 6 g, mix with 1 g of alginate oligosaccharide, and you get a foliar fertilizer.
[0054] Comparative Example 3
[0055] Take alkaline protease and flavor protease respectively, according to the mass ratio 2:1, to prepare a compound protease preparation with a total enzyme amount of 5000 U / g.
[0056] Take 10 g of yellow mealworm powder, add 100 mL of distilled water, add a complex protease preparation, and hydrolyze at 50°C and pH=8.5 for 3 h. Then, increase the temperature to 90°C and heat for 10 min to inactivate the enzyme. Use an ultrafiltration tube to retain the hydrolysis products with a molecular weight greater than 3 KD and less than 5 KD, and the yellow mealworm polypeptide is obtained.
[0057] Mix 6 g of the yellow mealworm polypeptide prepared above with 1 g of alginate oligosaccharide to obtain a foliar fertilizer.
[0058] Comparative Example 4
[0059] Take alkaline protease and flavor protease, respectively, and prepare a complex protease preparation with a total enzyme amount of 5000 U / g according to a mass ratio of 2:1.
[0060] Take 10 g of yellow mealworm powder, mix it with 0.1 mmol / L sodium bicarbonate solution 100 mL, and stand for 3 h. Then, add a complex protease preparation, hydrolyze at 50°C and pH=8.5 for 3 h, increase the temperature to 90°C, heat for 10 min to inactivate the enzyme, and use an ultrafiltration tube to retain the hydrolysis products with a molecular weight less than 3 KD, and the yellow mealworm polypeptide is obtained.
[0061] Mix 6 g of the yellow mealworm polypeptide prepared above with 1 g of alginate oligosaccharide to obtain a foliar fertilizer.
[0062] Experimental Example 1: Prevention and control of cucumber downy mildew
[0063] 1. Test design:
[0064] The test site is located in the Shaanxi Academy of Sciences Dali Biological Agricultural Research Demonstration Base in Qiangbai Town, Dali County, Weinan City. The test cucumbers were planted on August 20, 2024, and covered with black mulch. At the time of the test, the cucumbers were in the fruiting stage. All plot cultivation and management conditions were consistent.
[0065] Eleven treatments were designed. Treatment 1 was a water control; treatment 2 was 40% dimethomorph suspension concentrate diluted 1000 times; treatment 3 was 10% fluazinam suspension concentrate; treatments 4-10 were foliar fertilizers prepared according to Examples 2-8 of the present application, diluted 500 times, and sprayed on the leaves; and treatments 11-14 were foliar fertilizers prepared according to Comparative Examples 1-4 of the present application, diluted 500 times, and sprayed on the leaves.
[0066] A total of 2 applications were made during the test: the first spraying time was October 11, and the second spraying time was October 18.
[0067] 2. Investigation and analysis method
[0068] Each cell randomly investigated 10 strains of cucumber, from top to bottom, all leaf blades were investigated, and the percentage of lesion area on each leaf to the whole leaf area was used to grade, the grading method: 0 level: no disease; 1 level: lesion area accounts for less than 5% of the whole leaf area; 3 level: lesion area accounts for 6%-10% of the whole leaf area; 5 level: lesion area accounts for 11%-20% of the whole leaf area; 7 level: lesion area accounts for 21%-50% below of the whole leaf area; 9 level: lesion area accounts for more than 51% of the whole leaf area. And the disease index and control effect are calculated according to the following formula.
[0069] Disease index = ∑ (number of each level of diseased plants x the value of the disease level) / (total number of plants surveyed x the value of the highest level) x 100%.
[0070] Control effect = (1- (disease index before treatment of the control * disease index after treatment) / (disease index after treatment of the control * disease index before treatment)) x 100%.
[0071] 3. Results analysis
[0072] As shown in Table 1, different pesticide treatments can significantly reduce the disease index, but the control effect changes significantly with time. Seven days after spraying, the control effect of the foliar fertilizer prepared by the present application example 2-8 is significantly higher than that of the other two pesticides, indicating that the short-term effect is best. The control effect of the foliar fertilizer prepared by the present application comparative example 1-4 is significantly lower than that of the other two pesticides.
[0073] Disease control: all pesticides or foliar fertilizers control the disease index, which is significantly lower than the water control. Fourteen days after spraying, the control effect of the foliar fertilizer prepared by the present application example 2-8 is improved, and the disease index does not increase significantly, and the disease development almost stops. The control effect of 40% dimethomorph and 10% fluazinam is reduced to about 49.9%, and the attenuation amplitude is larger, and the disease index increases significantly (7.58 and 6.89), indicating that the control effect decays rapidly with time. The control effect of the foliar fertilizer of the present application comparative example 1-4 also decreases to different degrees. The foliar fertilizer prepared by the present application example 2-8 has short-term high efficiency and long-term persistence, and the control effect does not decrease but increases, indicating that the active ingredient may be more efficient or the mechanism of action is unique. By comparing the short-term and long-term control effects, the foliar fertilizer prepared by the present application example 5 has the best control effect on cucumber downy mildew.
[0074] Table 1 Control effect of different pesticides on cucumber downy mildew
[0075]
[0076] Different lowercase letters indicate that the difference is statistically significant.
[0077] Experimental example 2 Tomato leaf mold disease control
[0078] 1. Test design:
[0079] The test site was located in Xiabashivillage, Jiangcun Town, Huiyi District, Xi'an City. The test tomatoes were planted on June 25, 2024, and covered with black mulch. At the time of the test, the tomatoes were in the fruiting stage. All plots were cultivated and managed under uniform conditions.
[0080] Eleven treatments were designed, treatment 1 was water control; treatment 2 was 40% dimethomorph suspension concentrate diluted 1000 times; treatment 3 was 10% fluazinam suspension concentrate; treatments 4-10 were leaf fertilizers prepared by examples 2-8 of the present application, diluted 500 times, foliar spraying; treatments 11-14 were leaf fertilizers prepared by comparative examples 1-4 of the present application, diluted 500 times, foliar spraying.
[0081] A total of 2 times of pesticide application were performed during the test: the first spraying time was August 19, and the second spraying time was August 26.
[0082] 2. Investigation and analysis method
[0083] Ten tomato plants were randomly investigated in each plot, all leaf blades were investigated from top to bottom, and the disease index and control effect were calculated according to the following formula.
[0084] Disease index = ∑ (number of plants of each level x value of the disease level) / (total number of investigated plants x value of the highest level) x 100%.
[0085] Control effect = (1- (disease index before treatment of the control * disease index after treatment of the treatment) / (disease index after treatment of the control * disease index before treatment of the treatment)) x 100%.
[0086] 3. Result analysis
[0087] As shown in Table 2, different pesticide treatments can significantly reduce the disease index, but the difference in control effect changes with time is obvious. Seven days after spraying, the control effect of the leaf fertilizers prepared by examples 2-8 of the present application is significantly higher than that of the other two pesticides, indicating that the short-term effect is best. The control effect of the leaf fertilizers prepared by comparative examples 1-4 of the present application is significantly poorer than that of the other two pesticides.
[0088] Disease control: all the agents or foliar fertilizers controlled the disease index, which was significantly lower than the water control. 14 days after application, the control effect of the foliar fertilizer prepared by Example 2-8 of the present application was improved, and the disease index did not increase significantly, and the disease development almost stopped. The control effects of 40% dimethomorph and 10% fluazinam were both reduced to about 48%-49%, and the attenuation amplitude was larger, and the disease index increased significantly (17.29 and 17.91), indicating that the control effect rapidly declined with time. The foliar fertilizers of Comparative Examples 1-4 of the present application also had different degrees of decline in control effect. The foliar fertilizer prepared by Example 2-8 of the present application had short-term high efficiency and long-term persistence, and the control effect did not decline but increased, indicating that the active ingredient thereof might be more efficient or the mechanism of action was unique. By comparing the short-term and long-term control effects, the foliar fertilizer prepared by Example 5 had the best control effect on tomato leaf mold.
[0089] Table 2 Control effect of different agents on tomato leaf mold
[0090]
[0091] Different lowercase letters indicate that the difference is statistically significant.
[0092] The above-described examples only describe the preferred modes of the present application, and do not limit the scope of the present application. Without departing from the design spirit of the present application, various modifications and improvements to the technical solutions of the present application made by those skilled in the art shall fall within the protection scope determined by the claims of the present application.
Claims
1. A method for preparing a foliar fertilizer for improving disease resistance of a plant, characterized by, The method comprises the following steps: The yellow mealworm powder is mixed with a sodium bicarbonate solution, and then is left to stand, mixed with a compound protease preparation, adjusted in pH, subjected to enzymolysis, and subjected to ultrafiltration with a cutoff of 3 KD to 5 KD to retain the components with a molecular weight greater than 3 KD and less than 5 KD, thereby obtaining the yellow mealworm polypeptide; The yellow mealworm polypeptide is mixed with the alginate oligosaccharide, thereby obtaining the foliar fertilizer.
2. The production method according to claim 1, wherein The concentration of the sodium bicarbonate solution is 0.1 mmol / L.
3. The production method according to claim 1, wherein The compound protease preparation is composed of alkaline protease and flavor protease at a mass ratio of 2:1; and the total amount of the added enzyme is 5000 U / g.
4. The production method according to claim 1, wherein The enzymolysis is performed at a temperature of 50℃ and a pH of 8.5 for 3 h.
5. The production method according to claim 1, wherein The mass ratio of the yellow mealworm polypeptide to the alginate oligosaccharide is (2-8):
1.
6. A foliar fertilizer obtained by the preparation method according to any one of claims 1-5.
7. The foliar fertilizer according to claim 6 for use in improving the disease resistance of plants.
8. The foliar fertilizer according to claim 6 for use in preventing and treating cucumber downy mildew.
9. A method for improving plant disease resistance, characterized in that, The method comprises the step of applying the foliar fertilizer according to claim 6 to the leaves of the plants.
10. A method of controlling cucumber downy mildew, characterized by, The method comprises the step of applying the foliar fertilizer according to claim 6 to the leaves of the cucumber plants.