Resistance inducer against phytopathogenic microorganisms containing alkaline earth metal peroxide and iron-plant composite, and disease control method

Abstract

To provide a disease control method for vegetables / cereals that are agricultural or horticultural plants, against bacterial / mycotic diseases, where the method is free from phytotoxicity and contributes to reduction of environmental load in fields.SOLUTION: A resistance inducer against phytopathogenic microorganisms contains an agent A and an agent B in the following, where the application amounts per one horticultural plant are within the following ranges: the agent A is a formulation containing a peroxide such as CaO2, in an amount of 1 to 100 g / plant; and the agent B is a composite material (iron-PP composite material) obtained by mixing / reacting iron or an iron compound with a plant containing phenolic hydroxyl groups, in an amount of 1 to 100 g / plant; where the agent A is an active ingredient and contains 10 to 60 mass% of CaO2 and the like, and the iron content in the agent B is 1 to 20 mass%.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a plant pathogen resistance inducer containing a composite material obtained by reacting iron or an iron compound with a plant containing a phenolic hydroxyl group, and containing an alkaline earth metal peroxide such as calcium peroxide or magnesium peroxide as an active ingredient, and to a disease control method in which the resistance inducer is mixed with the soil in planting holes. [Background technology]

[0002] Bacterial wilt, a soil bacterial disease of solanaceous crops such as tomatoes and eggplants, causes damage on a global scale, resulting in enormous economic losses amounting to hundreds of billions of yen per year. The bacterial wilt fungus is a plant pathogen that invades the roots of plants and grows within the xylem. Plants infected with this fungus experience a blockage in the supply of water and other nutrients to the entire body due to bacterial proliferation within the xylem, causing the plant to wilt. The toxins released by the fungus cause necrosis of plant cells, ultimately resulting in the plant's death. Bacterial wilt is a difficult disease to eradicate once it has occurred, as the pathogen can survive deep underground for long periods and will re-emerge once a suitable host plant is planted.

[0003] Conventional techniques for controlling bacterial wilt include soil fumigation with chloropicrin, the use of resistant varieties, and the use of antibiotics, but all of these methods currently have many issues to be resolved in terms of control effectiveness, cost, environmental impact, etc. Under these circumstances, there is a need for the development of a control method that is inexpensive, has little impact on the environment, and is highly effective.

[0004] Meanwhile, disease resistance inducers have been attracting attention in recent years as an environmentally friendly pest control material. Disease resistance inducers are chemicals that exert disease control effects by increasing a plant's natural resistance to disease and inducing disease tolerance. Because they do not directly kill pathogens, they have the advantage of reducing the risk of the emergence of resistant bacteria, which can be a problem when using fungicides.

[0005] Examples of environmentally friendly agricultural materials include the use of alkaline earth metal peroxides such as calcium peroxide as oxygen suppliers to improve rice seedling establishment or as growth promoters for vegetables (Patent Documents 1 and 2, etc.). Other examples include the use of a combination of calcium peroxide and a reaction product of iron with coffee ingredients to control bacterial wilt of tomato (Patent Document 3, Non-Patent Documents 1 and 2), and the use of iron-polyphenols alone to control diseases such as rice seedling disease (Patent Documents 4 and 5).

[0006] Patent Document 3 and Non-Patent Documents 1 and 2 report that soil mixing of "coffee grounds and iron reaction products" and "calcium peroxide" is effective in controlling bacterial wilt of tomato. However, these studies were conducted in pot tests rather than in field trials, and the main bactericidal component is hydroxyl radicals generated by the Fenton reaction between hydrogen peroxide, which is produced by the decomposition of calcium peroxide, and divalent iron. In the technology described in Patent Document 3, since bacterial wilt bacteria are present throughout the soil, sufficient contact between the pathogen and the agent is required to achieve a sufficient control effect, and therefore, iron (coffee grounds and iron reaction products) and calcium peroxide must be mixed throughout the soil. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 1-262713 [Patent Document 2] Patent Application No. 2024-1641 [Patent Document 3] Japanese Patent Application Laid-Open No. 2011-212518 [Patent Document 4] Japanese Patent Application Publication No. 2020-158448 [Patent Document 5] Patent application No. 2022-159130 [Patent Document 6] Patent Publication No. 2021-155303 [Non-patent literature]

[0008] [Non-Patent Document 1] National Agriculture and Food Research Organization (NARO) press release, "(Research Results) Soil Disinfection with Coffee Grounds," NARO website, January 10, 2019 [Non-patent document 2] Claudio Morikawa, Kenji, "Polyphenol-iron complexes also have the effect of suppressing soil pathogens," Modern Agriculture, edited by the Rural Culture Association, January 2020, pp. 42-45 Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention uses alkaline earth metal peroxides such as calcium peroxide or magnesium peroxide as an active ingredient, A preparation containing a composite material obtained by mixing or reacting iron or an iron compound with a plant containing a phenolic hydroxyl group is used. The objective of the present invention is to find a disease control method for bacterial or fungal diseases of agricultural and horticultural plants such as vegetables or grains, which is simple, practical, and does not involve chemical damage, and which contributes to reducing the environmental load and work costs in farm fields. [Means for solving the problem]

[0010] The present inventors have discovered a simple and practical disease control method for bacterial or fungal diseases of agricultural and horticultural plants such as vegetables or grains, which contributes to reducing the environmental load and work costs in the field, by using a formulation containing a composite (iron-plant composite or iron-PP composite) obtained by mixing or reacting iron or an iron compound with a plant containing a phenolic hydroxyl group, and an alkaline earth metal peroxide such as calcium peroxide as an active ingredient.The method is summarized as follows.

[0011] [1] Contains the agents A and B below, The treatment amount of each agent per horticultural plant (or seedling) is shown below: Resistance inducers against plant pathogens: Agent A: Preparation containing calcium peroxide or magnesium peroxide: 1-100g / seed Agent B: Iron or iron compounds and plants containing phenolic hydroxyl groups Composites obtained by mixing or reacting (iron-PP composites): 1-100g / seed And, The agent A is an active ingredient, and the agent A contains calcium peroxide or magnesium peroxide in an amount of 10 to 60% by mass, The resistance inducer against plant pathogenic fungi, wherein the iron concentration in said agent B is 1 to 20 mass %.

[0012] [2] In the plant resistance inducer described in [1], the mixing ratio (mass ratio) of agent A and agent B is A resistance inducer in which the ratio of agent A to agent B is 1:0.1 to 1:10.

[0013] [3] In the plant resistance inducer described in [1], the mass of calcium peroxide or magnesium peroxide in agent A (M E ) to the mass of iron in agent B (M F ) mass ratio M F / M E is greater than or equal to 0.01 and less than or equal to 2.0.

[0014] [4] The plant resistance inducer against plant pathogens according to [1], wherein the plant containing a phenolic hydroxyl group is coffee or tea.

[0015] [5] A method for controlling bacterial or fungal diseases by mixing the resistance inducer against plant pathogens according to any one of [1] to [4] into planting holes and soil.

[0016] [6] The method for controlling a bacterial disease according to [5], wherein the bacterial disease is bacterial wilt of tomato.

[0017] [7] The method for controlling a fungal disease according to [5], wherein the fungal disease is sweet potato fusarium wilt. [Effects of the Invention]

[0018] Use of the plant pathogen resistance inducer of the present invention reduces phytotoxicity to agricultural and horticultural plants such as vegetables, and is useful as an agent for controlling bacterial or fungal diseases. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a cross-sectional view of a "ridge" 1 in which a "planting hole" 2 (the area indicated by the dashed rectangle (2 in a circle)) was dug in a "soil (field)" 10 using the "resistance inducer against plant pathogenic fungi" of the present invention, and agents A and B were scattered inside the "planting hole" 2, and plant 5 "seedlings" containing 3 "seedling raising soil" (the area indicated by the dashed rectangle (3 in a circle)) were scattered inside the "planting hole" 2. [Figure 2] This is a cross-sectional view of a "ridge" 1 in which 8 "agent A" and 9 "agent B" of the present invention have been mixed with soil and scattered into a "planting hole" 2 (spread over the walls and bottom of the soil hole), and a plant "seedling" 5 containing 3 "seedling raising soil" has been placed inside the "planting hole" 2. [Figure 3] This is a cross-sectional view of 1 "ridge" in which 8 "agent A" and 9 "agent B" of the present invention are mixed into 3 "seedling raising soil" and scattered into 2 "planting holes" of the same size as 3 "seedling raising soil". [Figure 4] This is a cross-sectional view of 1 "ridge" in which a planting hole was dug in 1 "ridge," and a mixture of 8 "agent A" and 9 "agent B" and soil was placed at the bottom of the hole, and 5 "seedling" and 3 "seedling raising soil" of the present invention were scattered on top of "agent 8A + agent 9B." [Figure 5] This is a cross-sectional view of "ridge" 1 of the present invention, in which "planting holes" 2 are dug in "ridge" 1, "seedlings" 5 and "seedling raising soil" 3 are placed in "planting holes" 2, and "agent A" 8 and "agent B" 9 are mixed with soil and scattered (covered) on top of "seedling raising soil" 3 (at the base of the seedlings). [Figure 6] This is a diagram of 50 "seedlings (after growth)" and 40 "roots (after growth)" that have grown beyond the 2 "planting hole" in the soil after the disease control method of the present invention has been applied, and is a schematic diagram showing the presence of a large number of 99 "bacteria (Ralstonia solanacearum)" (jagged granular) near 40 "roots" in the soil as an example of the cause of bacterial disease. [Figure 7]This is a simplified overhead (schematic) diagram showing an example of the present invention, in which 5 "seedlings" are planted in several 2 "planting holes" on 1 "ridge" in an actual 10 "field." DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments of the present invention will be described in detail, but the present invention is not limited to the following embodiments and can be implemented in various forms within the scope of the gist of the present invention.

[0021] The resistance inducer against plant pathogens of the present invention (hereinafter also simply referred to as the resistance inducer) comprises: It contains the agents represented by the following [Agent A] and [Agent B], and the treatment amount of each agent per 1 stalk (or 1 seedling) of agricultural and horticultural plants is represented as follows: Resistance inducers against plant pathogens: Agent A: Preparation containing calcium peroxide (CaO2) or magnesium peroxide (MgO2) (preparation containing alkaline earth metal peroxides): 1-100g / plant Agent B: Iron or iron compounds and plants containing phenolic hydroxyl groups Composite material obtained by mixing or reaction (iron-PP composite material): 1-100g / piece is.

[0022] The "agent A" included in the "resistance inducer against plant pathogenic fungi" of the present invention is an active ingredient, and is a preparation containing alkaline earth metal peroxides, specific representative examples of which are calcium peroxide or magnesium peroxide. Furthermore, the preparations containing these alkaline earth metal peroxides include alkaline earth metal peroxides; It is a mixture containing at least one of alkaline earth metal hydroxides, alkaline earth metal carbonates, and mineral substances. The form of agent A may be powder, or granular or particulate, and if granular or particulate, the particle size is preferably 1 mm to 10 mm.

[0023] Examples of methods for producing formulations containing calcium peroxide (CaO2) include the use of calcium hydroxide. Calcium (Ca(OH)2) and hydrogen peroxide (H2O2) aqueous solutions are mixed and reacted to form a slurry. Alternatively, the CaO2 may be prepared in a granular form, dehydrated, and then calcium hydroxide and calcium carbonate may be added as appropriate. Then, through steps such as granulation, drying, and grinding, a preparation consisting of a mixture (composition) containing at least one of calcium peroxide, calcium hydroxide, and calcium carbonate can be obtained. Additives such as sulfate hydrates may be added during the manufacturing process. The CaO2 content in the CaO2-containing preparation is preferably 10% by mass or more and 60% by mass or less of the total CaO2-containing preparation, and more preferably 15% by mass or more and 50% by mass or less.

[0024] Products containing magnesium peroxide (MgO2) can be produced using methods similar to those used for CaO2. For example, by mixing and reacting mainly magnesium hydroxide (Mg(OH)2) and an aqueous solution of hydrogen peroxide (H2O2), a preparation consisting of a mixture (composition) containing at least one of magnesium peroxide, magnesium hydroxide, and magnesium carbonate can be obtained (Patent Document 6). Additives such as sulfate hydrates may also be added during the production process.

[0025] The minerals (mineral substances) contained in these alkaline earth metal peroxide-containing formulations include calcium carbonate, clays (dry clay, wet clay), diatomaceous earth, talc, silica stone, silica sand, calcium carbonate, calcium sulfate (calcined gypsum), hydrated lime, olivine sand, vermiculite, shirasu attapulgite, rosewood, acid clay, activated clay, and fly ash, and these can be used singly or in combination of two or more types.

[0026] The resistance inducer of the present invention is, as "agent B", The iron-PP composite of the present invention contains a "composite obtained by mixing or reacting iron or an iron compound with a plant containing phenolic hydroxyl groups" (hereinafter also referred to simply as an iron-PP composite). The iron-PP composite of the present invention is preferably prepared by a method described in detail in Patent Document 4, in which "iron or an iron compound" and "a plant containing phenolic hydroxyl groups (or a polyphenol (PP) source, also simply referred to as PP; in Patent Document 4, it is referred to as a "polyphenol source")" are heated and mixed together with water to react with each other.

[0027] The "iron or iron compound" used as the raw material for the iron-PP composite of the present invention can be any iron or iron compound. Examples include metallic iron; water-soluble iron compounds such as iron(III) chloride (FeCl), iron(III) sulfate (Fe(SO)), iron(II) sulfate (FeSO), and iron(II) nitrate (Fe(NO)); water-insoluble iron compounds such as iron(III) oxide (FeO), iron(III) nitrate (Fe(NO)), iron(III) hydroxide (Fe(OH), FeO(OH)), and iron(II) hydroxide (Fe(OH)); hydrates of the above iron compounds; natural iron ores such as pyrite, marcasite, siderite, magnetite, and goethite; natural iron-containing materials such as soil, heme iron, and shells; and solutions of these in acid. Among these, iron(III) compounds such as iron(III) chloride and iron(III) sulfate are preferred, with iron(III) chloride being more preferred.

[0028] The "plant containing a phenolic hydroxyl group" of the present invention is not particularly limited as long as it is a common plant. Examples include woody or herbaceous materials or processed products thereof, grain raw materials such as malt, barley, and wheat, coffee beans, tea (tea leaves), hops, and wine lees, and mixtures of these can also be used. Coffee beans or tea are preferred as the "plant containing a phenolic hydroxyl group."

[0029] Examples of coffee beans include raw coffee beans, dried coffee beans, roasted coffee beans, roasted and ground coffee beans, extracts obtained by soaking these in water (drinkable coffee), dried and powdered extracts, coffee grounds, etc. Examples of tea leaves include raw tea leaves, dried tea leaves, fermented tea leaves, extracts obtained by soaking these in water (drinkable green tea, black tea, oolong tea, etc.), dried and powdered extracts, used tea leaves, etc.

[0030] The coffee grounds or used tea leaves may be used before or after extraction, or may have their moisture content adjusted by heating or other procedures before or after extraction. When using pre-extracted coffee grounds or used tea leaves, from the viewpoint of effective use of resources, it is preferable to use iron PP produced using non-standard products that are not intended for beverage use as raw materials, rather than those intended for beverage use.

[0031] In a method for producing the iron-PP composite of the present invention, for example, when coffee grounds are used as a plant (PP source) containing phenolic hydroxyl groups, an aqueous solution or dispersion of iron or an iron compound is mixed and contacted with the coffee grounds to obtain a reaction product, which is then heated for a certain period of time (e.g., at a temperature between 70°C and 200°C) and dried to a moisture content of a certain concentration or less (e.g., 20% by mass or less, preferably 15% by mass or less). A preferred specific production method is the method described in Patent Document 4. Alternatively, the iron-PP composite may be used as a resist derivative simply by mixing the iron or iron compound with the PP source.

[0032] The iron-PP composite material of the present invention, after being produced by the above-described production method, contains divalent iron ions (water-soluble iron ions) resulting from the reduction of trivalent iron derived from the iron or iron compound. The stable presence of divalent iron ions in the iron-PP composite material can be confirmed by subjecting the product to a pH stability test or by phenanthroline silver colorimetry. Furthermore, the amount of phenolic hydroxyl group-containing components contained in the raw plant material can be measured by analysis using methods such as the Folin-Denis method.

[0033] The properties of the iron-PP composite material of the present invention vary depending on the drying time during production, and the storage conditions and storage period after production. Therefore, drying or replenishment of moisture may be carried out as appropriate during storage, transportation, or before use as an agricultural or horticultural fungicide.

[0034] The iron concentration in the iron-PP composite material in "agent B" of the present invention is preferably 1% by mass or more and 20% by mass or less, more preferably 2% by mass or more and 16% by mass or less, and even more preferably 4% by mass or more and 10% by mass or less.

[0035] The plant resistance inducer containing "agent A" and "agent B" of the present invention will be described in detail below. In addition, a disease control method for plant pathogens using the plant resistance inducer of the present invention will also be described.

[0036] The resistance inducer of the present invention is characterized in that when planting seedlings of vegetables or grains such as rice as agricultural or horticultural plants in field soil, "agent A" and "agent B" are mixed or placed separately only inside the hole into which the seedlings will be planted, and then applied. In this case, the treatment (application) amount per plant seedling (or per seedling) is 1 to 100 g / plant of agent A and 1 to 100 g / plant of agent B. Details of the present invention will be specifically explained below using the simplified diagram of the present invention in Figure 1.

[0037] 1 to 5 are diagrams of the "disease control method" using the "resistance inducer" of the present invention, immediately after seedlings are first planted in the field. As described in the "Brief Description of the Drawings" section above, FIG. 6 is a schematic diagram of the seedlings after a certain period of growth. FIG. 7 is a schematic diagram showing a specific example of the state immediately after creating ridges in the field, digging planting holes in the ridges, treating with "agent A" and "agent B," and planting multiple seedlings. Generally, the field is an ordinary farm or farmland soil, such as a field used to grow vegetables or grains. A method for cultivating crops such as tomatoes and sweet potatoes involves creating one ridge of mounded soil in a cultivated and fertilized field, digging two planting holes, and planting five seedlings (including four roots and three seedling-raising soils) in a 10 cm diameter x 10 cm deep pot into one ridge. This method is a conventional and common cultivation method well known to farmers.

[0038] Figures 1 and 2 show cross-sectional views of a furrow 1 in which a planting hole 2 was dug in a soil (field) 10 using a plant pathogen resistance inducer, a feature of the present invention. The planting hole 2 was dug, and prescribed amounts of Agents A and B were dispersed within the planting hole 2. The agents were then uniformly mixed with the soil on the planting hole wall using a transplanting trowel or similar tool, ensuring the hole was not filled. A plant seedling 5 containing seedling soil 3 was then planted within the planting hole 2. In Figure 2, Agent A 8, a formulation containing alkaline earth metal peroxides such as calcium peroxide or magnesium peroxide, is represented by a white circle (○). Also, Agent B 9, an iron-PP composite, is represented by a diamond (◆). In this way, the resistance inducer of the present invention can be placed in the two planting holes and then mixed with an appropriate amount of soil, or a mixture of the resistance inducer of the present invention and an appropriate amount of soil can be placed in the planting holes in advance, and the seedlings can then be planted so that the resistance inducer of the present invention is located around (on the bottom and surrounding sides) the seedling soil of the seedlings to be planted.

[0039] The size of each ridge can be adjusted to suit the size and conditions of the crop and field. Any suitable height can be selected, such as 10cm or less, 20cm or less, or 30cm or less. Generally, mounded soil is laid out in rows in the field in long, straight lines, with one or two rows of planting holes drilled in each row and seedlings planted (see Figure 7 for example). The cross section of the ridges is rectangular or trapezoidal. The purpose of creating ridges is to increase the surface area that comes into contact with water and air on the sides, making water supply, drainage, and soil heating and cooling more efficient.

[0040] The holes for planting the seedlings (2 planting holes) may be the same size as holes for planting normal seedlings. Specifically, the diameter is 5 cm to 30 cm, and the depth is 5 cm to 30 cm. The size of the holes may be changed appropriately depending on the size of the seedling's roots. A diameter of 7 cm to 15 cm is preferable. The shape of the holes may be conical, cylindrical, or hemispherical to fit the seedling pot.

[0041] The seedlings (including 3 seedling medium, 4 roots, 6 leaves, and 7 stems) may be grown from vegetable or grain seeds or commercially available. Before planting, they are preferably grown in seedling pots or cell trays.

[0042] Figure 3 shows a specific example of applying the resistance inducer of the present invention. While the specific example of Figure 2 is a method in which Agents A and B are not mixed into the seedling raising soil, Agents A and B can also be applied (spread) to the seedlings, etc., so that the agents are located in the vicinity of the roots of the seedlings, etc., as in the method of Figure 3. Therefore, the resistance inducer of the present invention can be mixed into the seedling raising soil of the seedlings, etc., beforehand, and the seedlings can be raised, and then, at the time of planting, the seedlings, etc., can be planted together with the seedling raising soil into cultivation soil such as a field or a planter.

[0043] Figure 4 shows a specific example of applying the resistance inducer of the present invention. In the method of Figure 4, the resistance inducer is applied at the time of planting seedlings, etc. 5. When planting seedlings, etc., holes are made in the soil (field) 10, and the resistance inducers of the present invention (8 "Agent A" and 9 "Agent B") are placed in the bottom of two planting holes, so that the resistance inducers are located in the vicinity of the roots (lower parts) of the seedlings, etc., and the seedlings can be planted.

[0044] 5 shows a specific example of applying the resistance inducer of the present invention. The resistance inducer of the present invention (8 "Agent A" and 9 "Agent B") can be sprayed (as granules) around the seedlings (5) after planting (near the ground surface of the stems), or after spraying, the agent can be mixed into the soil so as not to damage the seedlings or other plants. Alternatively, a mixture of the resistance inducer of the present invention and an appropriate amount of soil can be mixed and then sprayed around the seedlings after planting.

[0045] In each of the above application methods, the two agents, "agent A" consisting of peroxide, which constitutes the resistance inducer of the present invention, and "agent B" consisting of an iron-PP composite material, may be mixed in advance to an appropriate amount and used, or appropriate amounts of "agent A" and "agent B" may be thoroughly mixed at the time of application. Alternatively, "agent A" and "agent B" may be applied as granules or other agents having an appropriate size and disintegrability by granulation, and appropriate additives may be selected and used for the granulation as needed. The mixing ratio (mass ratio) of "agent A" and "agent B" is The ratio of agent A to agent B may be 1:0.1 to 1:10, The ratio of agent A to agent B is preferably 1:0.2 to 1:5, A ratio of agent A to agent B of 1:1 to 1:5 is more preferable. If the soil is mixed before planting, the ratio can be any appropriate ratio. In the plant resistance inducer of the present invention, the mass of calcium peroxide or magnesium peroxide in agent A (M E ) to the mass of iron in agent B (M F ) mass ratio M F / M E is preferably 0.01 or more and 2.0 or less. For example, the mass M of CaO2 or MgO2 in agent A E When the amount is 7 to 11 g, the mass of iron in agent B, M F is preferably 0.07 to 22 g.

[0046] Furthermore, the plant resistance inducer of the present invention, Agent A or Agent B, may contain water before or after mixing or when mixing with the soil, and the water content may be appropriately set. The water used for the plant resistance inducer of the present invention is not particularly limited, and may be ordinary water for agricultural use, such as tap water or well water.

[0047] The resistance inducer of the present invention can be used by diluting it with water so that the iron-PP composite is contained at a concentration of 10 to 1000 times, preferably 10 to 200 times, when actually using "agent B." The iron concentration in the diluted solution is preferably 0.001% by mass to 2% by mass (10 ppm to 20,000 ppm).

[0048] By applying and using the plant pathogen resistance inducer of the present invention, the effects of planting hole treatment are enhanced compared to the techniques described in Patent Document 3 and Non-Patent Documents 1 and 2, significantly reducing the amount of chemicals applied to the soil or natural environment. As a concrete example of this effect, Figure 6 shows a diagram of a "seedling (after growth)" 50 and a "root (after growth)" 40 that has grown beyond the "planting hole" 2 in the soil after the disease control method of the present invention has been applied. Even if the "root (after growth)" 40 extends beyond the planting hole to the area treated with the chemical as the plant grows, as shown in Figure 6, the plant has already been conferred resistance, and infection (invasion) of tomato bacterial wilt (90 bacteria (Ralstonia solanacearum)) present throughout the soil can be prevented.

[0049] The disease control method of the present invention using the "resistance inducer against plant pathogens" is a localized application, unlike the overall soil treatment, and therefore there is no opportunity for the agent to come into contact with the bacterial wilt disease bacteria present over the entire soil surface, and is therefore based on a different concept from the methods that utilize the bactericidal action of the agent due to contact between the pathogen and the agent as described in Patent Document 3, Non-Patent Document 1, or Non-Patent Document 2. The present invention has been found to be able to obtain a very high control effect against bacterial diseases or fungal diseases, and that the disease control method using the agent of the present invention induces resistance to plant pathogens.

[0050] The resistance inducer of the present invention may be mixed with a solid or liquid carrier, and may contain other ingredients such as water and, if necessary, additives (auxiliaries) such as surfactants, dispersants, penetrants, spreaders, thickeners, antifreeze agents, binders, anti-caking agents, anti-decomposition agents, preservatives, anti-settling agents, and anti-foaming agents.

[0051] The resistance inducer of the present invention can be formulated in various forms by adding the above-mentioned additives (auxiliaries).Specific formulations of the fungicide include solutions, emulsifiable concentrates, wettable powders, suspensions (aqueous suspension formulations), water-soluble granules, water-dispersible granules, emulsions, suspoemulsions, dusts, granules, and gels.The fungicide can be used in any form, enclosed in a water-soluble package, or as a wet dressing.

[0052] The plant resistance inducer of the present invention can be used for treating various plants, including grains, vegetables, and the like, without any particular limitation.

[0053] The present invention is highly effective against bacterial and fungal diseases. Examples of bacterial diseases include bacterial wilt of solanaceae, such as bacterial wilt of tomato, and examples of fungal diseases include fusarium wilt of sweet potato and verticillium wilt of tomato.

[0054] The control effect of the resistance inducer of the present invention is evaluated using the control value. The control value is an index that represents the degree of control effect in a treated area against damage caused by diseases such as bacteria and fungi in an untreated area, and generally, the higher the control value, the greater the control effect. Control value = [100 - (disease severity in treated area / disease severity in untreated area) x 100] It is calculated using the formula: The higher the control value, the greater the control effect. [Example]

[0055] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[0056] [Formulation Examples 1 to 4, and Formulation Comparative Examples 2 and 3] As "Agent A," one of the following commercially available calcium peroxide preparations (manufactured by Hodogaya Chemical Co., Ltd.) was used. (Formulation Examples 1, 2, and 4) Product name: Calper Granules 16 (registered trademark "Calper") (The content of calcium peroxide (CaO2), an effective oxygen supplying agent, is 16% by mass of the mixture) (Formulation Example 3) Product name: Neocaloxo (registered trademark): (The content of calcium peroxide (CaO2), an effective oxygen supplying agent, is 20-30% by mass of the mixture)

[0057] For "Agent B," in Examples 1 to 3 and Comparative Example 1, an "iron-polyphenol (PP) composite (hereinafter abbreviated as iron-PP composite or "iron-PP")" (manufactured by Hodogaya Chemical Co., Ltd.) was used, which was manufactured by the method described in Patent Document 4, specifically by reacting iron chloride (III) (FeCl3) (manufactured by Kanto Chemical Co., Ltd.) with substandard coffee powder (before use). The bulk density of the iron-PP composite was 0.43 g / cm. 3 Measurement of the iron concentration ratio using the phenanthroline colorimetric method revealed that the iron-PP composite contained approximately 90% to 95% iron (high in divalent iron) with a ratio of Fe(II) / [Fe(II) + Fe(III)] of approximately 90% to 95%. Preparation Example 4 is a preparation that simply mixes the iron(III) chloride and the coffee powder (referred to as "PP"). Preparation Comparative Example 3 is a preparation prepared from non-standard coffee powder (referred to as "PP") that was scheduled to be discarded before use, which is the raw material for producing the iron PP.

[0058] Table 1 shows the composition and mixing ratio of Agent A and Agent B in each of the prepared formulations. In Table 1, the number in parentheses in the Agent A (g) column represents the amount of calcium peroxide (g) contained, and the number in parentheses in the Agent B (g) column represents the amount of iron (g) contained.

[0059] [Table 1]

[0060] [Example 1] <Tomato bacterial wilt control test> The required number of containers (57cm x 39cm x 25cm deep) were prepared and filled with soil contaminated with tomato bacterial wilt (the bacterial wilt bacteria were cultured in SMB medium with shaking, and the collected bacterial suspension was mixed with the soil to adjust the bacterial density in the soil to 103 cfu / g soil, which was used as the test soil). The test plots were set up in six replicates, with four plants (25cm spacing between plants) per container. On June 28, planting holes large enough to accommodate 9 cm pots were dug in the containers (four holes per container) with a transplanting trowel. Agents A and B from the formulation examples or comparative formulations listed in Table 1 were scattered into the planting holes at the specified ratios and gently mixed by hand with the soil in the planting holes just before planting. After treatment, tomato seedlings (Momotaro 8: own-root cultivation) were planted. From July 31 (34 days after planting) to September 12 (the end of the survey), the proportion of infected plants and the incidence of bacterial wilt were investigated for all plants in each plot every week, based on an index. The disease severity and control value were calculated according to the following formula. Chemical damage was visually observed after treatment and during the survey. The results are shown in Table 2.

[0061] Severity of disease = [Σ (number of plants by disease severity × index) / (number of plants surveyed × 4)] × 100 index 0: Healthy 1: Wilting of the shoot tip is observed 2: Wilting of leaves is observed 3: The entire plant becomes wilted. 4: Withering Control value = {1 - (disease severity in treated area) / (disease severity in untreated area)} x 100 Phytotoxicity: Phytotoxicity was visually inspected throughout the test period. - : No drug-related harm acknowledged +: Minor drug-related symptoms observed ++: Moderate adverse reactions observed +++: Severe drug-related symptoms observed

[0062] [Table 2]

[0063] [Example 2] A field contaminated with tomato bacterial wilt was prepared, and the required number of ridges (ridge width 1 m) were made. The test plots consisted of 12 plants (40 cm between plants) per plot, arranged in four rows. On September 4, each ridge was divided into 1 m x 3 m sections, and planting holes large enough to accommodate 9 cm pots were dug into the surface of the ridges with a transplanting trowel (12 holes per section). The prescribed ratios of Formulation Examples A and B listed in Table 1 were scattered into the planting holes immediately before planting, and the mixture was gently mixed by hand with the soil in the planting holes. After treatment, tomato seedlings (Momotaro 8: own-root cultivation) were planted. From September 18 (the first day of disease) to November 8, the proportion of infected plants and the incidence of bacterial wilt were investigated at 10-day intervals for all plants in each section, according to the index. The methods for evaluating disease severity, control value, and phytotoxicity were as described in Example 1.

[0064] [Table 3]

[0065] [Example 3] A field contaminated with tomato bacterial wilt was prepared, and the required number of ridges (ridge width 1.7 m) were made. The test plots consisted of 20 plants (40 cm between plants) per plot, set up in triplicate. On May 19, each ridge was divided into 4 m x 1.7 m sections, and planting holes large enough to accommodate 9 cm pots were dug on the surface of the ridges with a transplanting trowel (20 holes per section). The prescribed ratios of Formulations A and B from the Examples listed in Table 1 were scattered into the planting holes immediately before planting, and then gently mixed with the soil in the holes by hand. After treatment, tomato seedlings (Momotaro 8: own-root cultivation) were planted. From June 10 (the first day of disease) to July 26, the proportion of infected plants and the incidence of bacterial wilt were investigated at seven-day intervals for all plants in each section, according to the disease index. The methods for evaluating disease severity, control value, and phytotoxicity were as described in Example 1.

[0066] [Table 4]

[0067] [Example 4] The required number of containers (57cm x 39cm x 25cm deep) were prepared and filled with soil contaminated with tomato bacterial wilt (the bacterial wilt bacteria were cultured in SMB medium with shaking, and the collected bacterial suspension was mixed with the soil to adjust the bacterial density in the soil to 103 cfu / g soil, which was used as the test soil). The test plots were set up in six replicates, with four plants (25cm spacing between plants) per container. On June 12, planting holes large enough to accommodate 9 cm pots were dug in the containers (four holes per container) with a transplanting trowel. Agents A and B from the formulation examples listed in Table 1 were scattered into the planting holes at the prescribed ratios and gently mixed by hand with the soil in the holes just before planting. After treatment, tomato seedlings (Momotaro 8: own-root cultivation) were planted. From June 12 (planting day) to August 28, the percentage of infected plants and the incidence of bacterial wilt were investigated for all plants in each plot every week, based on an index. The severity of disease and control value were calculated according to the following formula. Chemical damage was visually observed after treatment and during the investigation. The results are shown in Table 5.

[0068] [Table 5]

[0069] As can be seen from Tables 2 to 5, the resistance inducer of the present invention has a high control effect against tomato bacterial wilt. [Industrial Applicability]

[0070] The plant resistance inducer of the present invention, which contains a composite (iron-PP composite) obtained by mixing or reacting an alkaline earth metal peroxide such as calcium peroxide, iron or an iron compound, and a plant containing a phenolic hydroxyl group, is effective as a plant resistance inducer against pathogenic fungi and is useful as an agent that can be used easily and stably for a long period of time. Furthermore, the disease control method of the present invention using the resistance inducer is effective as a disease control method that causes little phytotoxicity to vegetables, controls infectious diseases such as fungal diseases and bacterial diseases, and does not cause any phytotoxicity to vegetables, etc. The plant pathogen resistance inducer of the present invention can also be applied to vegetables, fruit trees, fruits, etc. [Explanation of symbols]

[0071] 1 ridge 2 Planting holes 3 Seedling growing soil 4 roots 5 Seedlings (above ground) 6 leaves 7 stems 8 Agent A 9. Agent B 10 Soil (field) 40 Roots (after growth) 50 seedlings (aerial part, after growth) 99 Bacteria (bacterial wilt)

Claims

1. Contains the agents A and B below, The treatment amount of each agent per horticultural plant (or per seedling) is shown below: Resistance inducers against plant pathogens: Agent A: Preparation containing calcium peroxide or magnesium peroxide: 1-100g / plant Agent B: Iron or an iron compound and a plant containing a phenolic hydroxyl group Composite material obtained by mixing or reacting (iron-PP composite material): 1-100g / plant And, The agent A is an active ingredient, and the agent A contains calcium peroxide or magnesium peroxide in an amount of 10 to 60% by mass, A resistance inducer against plant pathogenic fungi, wherein the iron concentration in the agent B is 1 to 20 mass%.

2. In the plant resistance inducer according to claim 1, the mixing ratio (mass ratio) of agent A to agent B is: A resistance inducer in which the ratio of agent A to agent B is 1:0.1 to 1:

10.

3. In the plant resistance inducer according to claim 1, the mass of calcium peroxide or magnesium peroxide in agent A (M Ｅ ) to the mass of iron in agent B (M Ｆ ) mass ratio M Ｆ / M Ｅ is 0.01 or more and 2.0 or less.

4. The plant pathogen resistance inducer according to claim 1, wherein the plant containing a phenolic hydroxyl group is coffee or tea.

5. A method for controlling bacterial or fungal diseases by mixing the resistance inducer against plant pathogens according to any one of claims 1 to 4 into soil in a planting hole.

6. The method for controlling a bacterial disease according to claim 5, wherein the bacterial disease is bacterial wilt of tomato.

7. The method for controlling a fungal disease according to claim 5, wherein the fungal disease is sweet potato fusarium wilt.

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