Agricultural composition and aqueous dispersion for agriculture

Abstract

Provided is an agricultural composition capable of controlling the supply of a biostimulant to a plant in accordance with conditions of high-temperature stress or low-temperature stress. An agricultural composition characterized in that the agricultural composition is composed of a temperature-responsive base material that begins to melt or decompose at a predetermined temperature, and contains a biostimulant that alleviates abiotic stress of plants or promotes growth of plants.

Description

Technical Field

[0001] The present invention relates to an agricultural composition and an aqueous dispersion used to improve the yield and quality of agricultural products. Background Art

[0002] Fertilizers and pesticides have been used in agriculture since ancient times to improve harvest yields and quality. Fertilizers and pesticides are typically used based on their intended purpose. For example, fertilizers, primarily containing nitrogen, phosphorus, and potassium, are used to provide crops (including trees and agricultural and forestry products, hereinafter referred to as "crops, etc.") with the nutrients they need for healthy growth. Furthermore, pesticides, such as fungicides, insecticides, and other agents, are used to directly control fungi, nematodes, mites, insects, rodents, other plants, animals, or viruses (pests and diseases) that harm crops.

[0003] Fertilizers and pesticides are classified into various categories according to their expected effects, and therefore the types of fertilizers and pesticides must be changed each time according to the desired effects.

[0004] Consequently, in recent years, biostimulants, as an alternative to fertilizers and pesticides, have been attracting global attention, primarily in Europe, as emerging agricultural materials. Biostimulants are various substances and microorganisms that enhance the physiological state of plants and soil. Biostimulants are characterized by their beneficial effects on plant health, stress tolerance, harvest yield and quality, post-harvest status, and storage by leveraging the inherent natural forces of plants and their surrounding environment.

[0005] Among environmental stresses, high temperature stress is caused by rising environmental temperatures, so it is important to supply biostimulants before the environmental temperature rises. However, since it is difficult to accurately predict the weather, a method of supplying biostimulants is used, for example, once every 1 to 2 weeks.

[0006] However, if the weather conditions do not predict the high temperature stress and the conditions continue, the supplied biostimulant is wasted. Therefore, it is necessary to control the supply of the biostimulant.

[0007] As a method for controlling the supply of active ingredients such as pesticides and fertilizers, for example, Patent Document 1 discloses a composition for slow-release, sustained-release, or controlled-release of active ingredients. Furthermore, Patent Document 2 discloses a controlled-release biodegradable composition that releases active ingredients into the soil at a controlled rate. Furthermore, Patent Document 3 discloses a biodegradable coating composition having a controlled release rate.

[0008] Furthermore, Patent Document 4 discloses a coated pesticide or coated fertilizer in which the temperature dependence of the elution rate of the active ingredient is small.

[0009] Furthermore, Patent Document 5 discloses a composition that releases an active ingredient after a certain period of time of administration but does not release the active ingredient during a certain period of time.

[0010] Prior art literature Patent Literature Patent Document 1: Japanese Patent Application No. 2019-523275 Patent Document 2: Japanese Patent No. 2995423 Patent Document 3: Japanese Patent Application No. 2021-501246 Patent Document 4: International Publication No. 2020 / 032224 Patent Document 5: Japanese Patent Application No. 2019-515928 Summary of the Invention Problems to be solved by the invention However, the compositions of Patent Documents 1-3 are materials that slowly release their active ingredients, and therefore continuously release them. Therefore, they are not designed to begin releasing active ingredients when conditions such as high temperature stress occur. In other words, the compositions of Patent Documents 1-3 are not capable of delivering active ingredients in response to high temperature stress.

[0011] Furthermore, since the material disclosed in Patent Document 4 has a low temperature dependency of the elution rate of the active ingredient, it is not possible to supply the active ingredient in response to high temperature stress conditions.

[0012] Furthermore, since Patent Document 5 is a material in which the supply of active ingredients is controlled according to time, it is not possible to supply active ingredients in response to a high temperature stress situation.

[0013] Furthermore, when growing plants in low-temperature environments, if the ambient temperature drops too low depending on the weather, the plants may experience cold stress. In the case of cold stress, it is important to supply biostimulants before the ambient temperature drops. However, as with high-temperature stress, accurate weather forecasting is difficult. Therefore, if, for example, biostimulants are supplied once every one to two weeks, the supplied biostimulant is wasted if, contrary to forecasts, the weather continues without the application of cold stress. Therefore, biostimulant supply must be controlled.

[0014] Therefore, an object of the present invention is to provide an agricultural composition capable of controlling the supply of a biostimulant to plants in response to conditions of high temperature stress or low temperature stress.

[0015] Means used to solve problems The above-mentioned problems are solved by the following present invention.

[0016] That is, the present invention (1) provides an agricultural composition characterized in that: The agricultural composition is composed of a temperature-responsive base material that begins to melt or decompose at a predetermined temperature. The agricultural composition includes a biostimulant that alleviates abiotic stress on plants or promotes plant growth.

[0017] In addition, the present invention (2) provides the agricultural composition of (1), characterized in that the temperature-responsive substrate is a material that does not dissolve or decompose at a temperature lower than the predetermined temperature and begins to dissolve or decompose when the temperature rises and reaches the predetermined temperature, and the melting start temperature or decomposition start temperature of the temperature-responsive substrate is 30 to 60°C.

[0018] In addition, the present invention (3) provides the agricultural composition of (1), characterized in that the temperature-responsive substrate is a material that does not dissolve or decompose at a temperature higher than the predetermined temperature and begins to dissolve or decompose when the temperature decreases and reaches the predetermined temperature, and the melting start temperature or decomposition start temperature of the temperature-responsive substrate is 0 to 20°C.

[0019] In addition, the present invention (4) provides the agricultural composition according to any one of (1) to (3), wherein the biostimulant is a compound that induces heat shock proteins.

[0020] In addition, the present invention (5) provides the agricultural composition according to any one of (1) to (3), wherein the temperature-responsive substrate is composed of a gel containing water and a gelling agent.

[0021] In addition, the present invention (6) provides an agricultural aqueous dispersion characterized in that: The agricultural aqueous dispersion comprises the agricultural composition described in any one of (1) to (3), The agricultural composition is dispersed in an aqueous solvent.

[0022] Effects of the Invention According to the present invention, it is possible to provide an agricultural composition capable of controlling the supply of a biostimulant to plants in response to conditions of high temperature stress or low temperature stress. DETAILED DESCRIPTION

[0023] The agricultural composition of the present invention is characterized in that The agricultural composition is composed of a temperature-responsive base material that begins to melt or decompose at a predetermined temperature. The agricultural composition includes a biostimulant that alleviates abiotic stress on plants or promotes plant growth.

[0024] The agricultural composition of the present invention includes a biostimulant (also referred to as a biostimulant). In other words, in the agricultural composition of the present invention, at least the biostimulant is dispersed and incorporated into a temperature-responsive substrate. In other words, the agricultural composition of the present invention includes at least a temperature-responsive substrate and a biostimulant dispersed within the temperature-responsive substrate. Furthermore, the agricultural composition of the present invention includes two types: one in which the temperature-responsive substrate begins to melt or decompose when the ambient temperature rises and reaches a predetermined temperature (the first agricultural composition of the present invention); and one in which the temperature-responsive substrate begins to melt or decompose when the ambient temperature drops and reaches a predetermined temperature (the second agricultural composition of the present invention). Furthermore, when the first and second agricultural compositions of the present invention are collectively referred to, they are referred to as the agricultural composition of the present invention.

[0025] The biostimulant is a compounding agent that, when the agricultural composition of the present invention is sprayed directly onto plants or onto soil or nutrient solution for plant growth, causes the temperature-responsive substrate to melt or decompose when the ambient temperature reaches a predetermined temperature and be supplied to the plants, soil, or nutrient solution, thereby alleviating environmental stress on the plants or promoting plant growth.

[0026] Biostimulants are a new type of agricultural material that has recently gained global attention, primarily in Europe. Biostimulants are a variety of substances and microorganisms that improve the physiological state of plants and soil. Biostimulants are characterized by their beneficial effects on plant health, stress tolerance, harvest quantity and quality, post-harvest status, and storage by leveraging the inherent natural forces of plants and their surroundings.

[0027] Biostimulants are substances or microorganisms that alleviate abiotic stress (environmental stress) by providing nutrients to plants, promote plant growth by improving their ability to acquire nutrients, and improve plant physiological conditions, thereby alleviating or promoting abiotic stress. Examples of abiotic stress (environmental stress) include high temperature stress, high humidity stress, salt stress, drought stress, low temperature stress, chilling stress, frost stress, oxidative stress (damage caused by reactive oxygen species), physical barriers (hail and wind damage), and stress caused by pesticides. Biostimulants alleviate these abiotic stresses (environmental stress) and promote plant growth. Furthermore, biostimulants promote plant growth by improving the rhizosphere environment, for example by promoting the development of soil microorganisms, stabilizing rhizobia, increasing root mass, enhancing root activity, inducing hormones that regulate stomatal opening and closing, and improving desiccation resistance. Biostimulants also improve plant physiological conditions, mitigate abiotic stress, and promote plant growth by activating photosynthesis, promoting flowering or fruit set, controlling transpiration, adjusting osmotic pressure, and synthesizing starch, which is disliked by aphids. Furthermore, biostimulants contribute to improved harvest yield and quality by alleviating abiotic stress, improving plants' ability to absorb nutrients, and promoting a better physiological state. Furthermore, biostimulants are materials that act on at least one of "alleviating abiotic stress," "improving plants' ability to absorb nutrients," and "improving plants' physiological state." Depending on the type of biostimulant, some may excel at one, two, or all of these three effects.

[0028] On the other hand, pesticides are materials that alleviate biotic stress, fertilizers are materials that provide nutrients to plants, and soil conditioners are materials that change the physical, chemical, or biological properties of the soil. In this sense, biostimulants are distinct from pesticides, fertilizers, and soil conditioners.

[0029] Furthermore, biostimulants are not materials that directly act on various agricultural problems to achieve the desired effects, but rather materials that achieve the desired effects by enhancing the abilities of plants themselves.

[0030] Therefore, according to the agricultural composition of the first embodiment of the present invention, which contains the aforementioned biostimulant, the biostimulant is supplied to plants when a high-temperature stress situation occurs due to an increase in ambient temperature. This imparts tolerance to high-temperature stress to the plants, allowing them to grow even in environments (temperatures) subject to high-temperature stress. Furthermore, according to the agricultural composition of the second embodiment of the present invention, which contains the aforementioned biostimulant, the biostimulant is supplied to plants when a low-temperature stress situation occurs due to a decrease in ambient temperature. This imparts tolerance to low-temperature stress to the plants, allowing them to grow even in environments (temperatures) subject to low-temperature stress.

[0031] There are no particular limitations on biostimulants and they may be selected appropriately. Examples of biostimulants include compounds that induce heat shock proteins. Examples of compounds that induce heat shock proteins include zingerone, sanguinarine, salicylic acid, polyamines, geldanamycin, isothiocyanates, trimethylglycine, perillaldehyde, citral, carotene, lycopene, zeaxanthin, cryptoxanthin, lutein, phenylethyl isothiocyanate, ursolic acid, choline, alginic acid, fulvic acid, humic acid, 5-aminolevulinic acid, oxidized glutathione, trehalose, and 2-hexenal.

[0032] Heat shock proteins are produced when cells are under stress, binding to modified proteins and playing a role in repairing the modified proteins. Moreover, compounds that induce heat shock proteins induce the production of heat shock proteins. Stress tolerance is therefore improved. That is, compounds that induce heat shock proteins are particularly effective in alleviating environmental stresses such as high temperature stress, high humidity stress, salt stress, and desiccation stress. Known heat shock proteins include zingerone, sanguinarine, salicylic acid, polyamines, geldanamycin, isothiocyanates, trimethylglycine, perillaldehyde, citral, carotene, lycopene, zeaxanthin, cryptoxanthin, lutein, phenylethyl isothiocyanate, ursolic acid, choline, alginic acid, fulvic acid, humic acid, 5-aminolevulinic acid, oxidized glutathione, trehalose, and 2-hexenal.

[0033] For example, when plant cells are subjected to heat shock, heat shock factors are activated within the cytoplasm and separated into HSP70 (heat shock protein), HSP90 (heat shock protein), and HSF (heat shock factor). HSFs bind to each other to form subunits with a predetermined three-dimensional structure. These subunits then translocate to the nucleus and bind to HSE sequences in the plant genome. Binding of these HSF subunits to HSE sequences activates genes involved in heat shock resistance. Specifically, these genes can produce heat shock proteins to repair damaged proteins, produce antimicrobial substances (proteins with antimicrobial properties) to prevent infection by pathogens, or produce proteins that eliminate reactive oxygen species. This improves tolerance to environmental stress.

[0034] Furthermore, heat shock protein-inducing compounds act on plant cells to produce HSFs. The produced HSFs bind to each other to form subunits with a predetermined three-dimensional structure. These subunits then translocate to the nucleus and bind to HSE sequences in the plant genome. Binding of these HSF subunits to the HSE sequences activates genes involved in combating heat shock, leading to the production of heat shock proteins. Thus, heat shock protein-inducing compounds are absorbed by plant cells, inducing the production of heat shock proteins.

[0035] Examples of heat shock proteins include heat shock protein 40, heat shock protein 70, heat shock protein 32, heat shock protein 47, and heat shock protein 60. Compounds that induce heat shock proteins induce heat shock proteins in the same manner as when exposed to a high temperature environment.

[0036] In the agricultural composition of the present invention, the heat shock protein-inducing compound itself may be blended and dispersed in the temperature-responsive substrate, or it may be blended and dispersed in the temperature-responsive substrate in the form of a formulation containing the heat shock protein-inducing compound as an active ingredient. Alternatively, the heat shock protein-inducing compound may be blended and dispersed in the temperature-responsive substrate by mixing a formulation containing the heat shock protein-inducing compound as an active ingredient with the temperature-responsive substrate and then removing the dispersion medium from the formulation. Commercially available formulations containing the heat shock protein-inducing compound as an active ingredient include THERMOZYMES, SUZUMIDORI, and SKEEPON.

[0037] The content of the heat shock protein-inducing compound in the agricultural composition of the present invention is not particularly limited and is appropriately selected depending on the environment in which the agricultural composition is used, the type of temperature-responsive substrate, and the like. The content, based on the active ingredient, i.e., based on the heat shock protein-inducing compound, is preferably 0.00005 to 1.0% by mass, and more preferably 0.0001 to 0.5% by mass.

[0038] Examples of biostimulants include zingerone, zingerone analogs, zingerone derivatives, zingerone salts, zingerone analog salts, and zingerone derivative salts. Zingerone (6CI, 7CI) is (2E,6E,10E)-2,6,9,9-tetramethylcycloundecane-2,6,10-trien-1-one (empirical formula (Hill method): C 15 H 22 O, CAS registration number: 471-05-6), is a substance represented by the following formula (1): [Chemical Formula 1]

[0039] In addition, as an analogue of zingerone, α-humulene can be mentioned: [Chemical Formula 2]

[0040] β-Caryophyllene: [Chemical Formula 3]

[0041] Myrcene D: [Chemical Formula 4]

[0042] Caryophyllene oxide: [Chemical Formula 5]

[0043] Cobutone: [Chemical Formula 6]

[0044] Salts of zingerone, salts of zingerone analogs, and salts of zingerone derivatives are not particularly limited. Examples include inorganic acid salts such as carbonates, hydrochlorides, nitrates, sulfates, and phosphates, and organic acid salts such as acetates, propionates, butyrates, and other aliphatic acid salts. Zingerone, zingerone analogs, zingerone derivatives, salts of zingerone analogs, and salts of zingerone derivatives are particularly effective in alleviating environmental stresses such as high temperature stress, low temperature stress, high humidity stress, salt stress, and desiccation stress.

[0045] Zingerone and its analogs comprise 80% to 90% by mass of the essential oil of red ginger and are available as extracts and ground products of plants in the Zingiberaceae family, such as ginger and turmeric. Zingerone and its analogs are also available as extracts and ground products of hops, cloves, and lavender.

[0046] In the agricultural composition of the present invention, zingerone, zingerone analogs, zingerone derivatives, zingerone salts, zingerone analog salts, and zingerone derivative salts may be blended and dispersed in the temperature-responsive base material as such, or in the form of a blending agent containing zingerone, zingerone analogs, zingerone derivatives, zingerone salts, zingerone analog salts, and zingerone derivative salts as active ingredients. Alternatively, zingerone, zingerone analogs, zingerone derivatives, zingerone salts, zingerone analog salts, and zingerone derivative salts may be blended and dispersed in the temperature-responsive base material after a blending agent containing zingerone, zingerone analogs, zingerone derivatives, zingerone salts, zingerone analog salts, and zingerone derivative salts as active ingredients is mixed with the temperature-responsive base material and then the dispersion medium in the blending agent is removed, whereby zingerone, zingerone analogs, zingerone derivatives, zingerone salts, zingerone analog salts, and zingerone derivative salts are blended and dispersed in the temperature-responsive base material. Examples of compounding agents containing zingerone, zingerone analogs, zingerone derivatives, zingerone salts, salts of zingerone analogs, and / or salts of zingerone derivatives as active ingredients include Stress Free-Z (registered trademark) (manufactured by Fuso Chemical Industries, Ltd.) and Stress Free-HE (registered trademark) (manufactured by Fuso Chemical Industries, Ltd.).

[0047] The content of zingerone, zingerone analogs, zingerone derivatives, zingerone salts, salts of zingerone analogs, and salts of zingerone derivatives in the agricultural composition of the present invention is not particularly limited and is appropriately selected depending on the use environment of the agricultural composition, the type of temperature-responsive substrate, etc., and is preferably 0.00005 to 1.0% by mass, more preferably 0.0001 to 0.5% by mass, based on the active ingredient. In addition, when the agricultural composition of the present invention contains one selected from the group consisting of zingerone, analogues of zingerone, derivatives of zingerone, salts of zingerone, salts of analogues of zingerone, and salts of derivatives of zingerone as a biostimulant, the amount of active ingredient refers to the content of one of them. Moreover, when the agricultural composition of the present invention contains two or more selected from the group consisting of zingerone, analogues of zingerone, derivatives of zingerone, salts of zingerone, salts of analogues of zingerone, and salts of derivatives of zingerone, it refers to the total amount of these zingerone, analogues of zingerone, derivatives of zingerone, salts of zingerone, salts of analogues of zingerone, and salts of derivatives of zingerone.

[0048] Examples of biostimulants include glycine betaine (also known as trimethylglycine), glycine betaine derivatives, glycine betaine salts, and salts of glycine betaine derivatives. Salts of glycine betaine are not particularly limited, and examples include inorganic acid salts such as carbonates, hydrochlorides, nitrates, sulfates, and phosphates, and organic acid salts such as acetates, propionates, butyrates, and other aliphatic acid salts. Glycine betaine, glycine betaine derivatives, glycine betaine salts, and salts of glycine betaine derivatives are particularly effective in alleviating environmental stresses such as high temperature stress, low temperature stress, high humidity stress, salt stress, and desiccation stress.

[0049] In the agricultural composition of the present invention, glycine betaine, a derivative of glycine betaine, a salt of glycine betaine, or a salt of a derivative of glycine betaine may be blended and dispersed in the temperature-responsive substrate as such, or in the form of a blending agent containing glycine betaine, a derivative of glycine betaine, a salt of glycine betaine, or a salt of a derivative of glycine betaine as an active ingredient. Alternatively, glycine betaine, a derivative of glycine betaine, a salt of glycine betaine, or a salt of a derivative of glycine betaine may be blended and dispersed in the temperature-responsive substrate by removing the dispersion medium from the blending agent after mixing a blending agent containing glycine betaine, a derivative of glycine betaine, a salt of glycine betaine, or a salt of a derivative of glycine betaine as an active ingredient with the temperature-responsive substrate. Examples of compounding agents containing the above-mentioned glycine betaine, a derivative of glycine betaine, a salt of glycine betaine, and / or a salt of a derivative of glycine betaine as an active ingredient include Sakata Liquid Fertilizer GB (registered trademark) (manufactured by Sakata Seed Co., Ltd.).

[0050] The content of glycine betaine, glycine betaine derivatives, glycine betaine salts, and glycine betaine derivative salts in the agricultural composition of the present invention is not particularly limited and is appropriately selected depending on the environment in which the agricultural composition is used, the type of temperature-responsive substrate, and the like. The content, based on the active ingredient, is preferably 0.00005 to 1.0% by mass, and more preferably 0.0001 to 0.5% by mass. Furthermore, when the agricultural composition of the present invention contains one selected from the group consisting of glycine betaine, glycine betaine derivatives, glycine betaine salts, and glycine betaine derivative salts as a biostimulant, the active ingredient amount refers to the content of one such active ingredient. Furthermore, when the agricultural composition of the present invention contains two or more selected from the group consisting of glycine betaine, glycine betaine derivatives, glycine betaine salts, and glycine betaine derivative salts, the amount refers to the total amount of these glycine betaine, glycine betaine derivatives, glycine betaine salts, and glycine betaine derivative salts.

[0051] Examples of biostimulants include sanguinarine, its derivatives, its salts, and salts of its derivatives. Sanguinarine is 13-methyl-[1,3]benzodioxolo[5,6-c]-1,3-dioxolo[4,5-i]phenanthridinium (CAS No. 2447-54-3). Sanguinarine salts are not particularly limited, and examples include inorganic acid salts such as carbonates, hydrochlorides, nitrates, sulfates, and phosphates, and organic acid salts such as acetates, propionates, butyrates, and other aliphatic acid salts. Sanguinarine, its derivatives, its salts, and salts of its derivatives are particularly effective in alleviating environmental stresses such as high temperature stress, low temperature stress, high humidity stress, salt stress, and desiccation stress.

[0052] Sanguinarine and its salts can be any of naturally derived substances such as natural extracts, chemically synthesized products, or microbially derived substances obtained through microbial fermentation. Sanguinarine is found in plants such as Macleaya cordata, Eschscholzia californica, Chelidonium majus, and Sangurinaria canadensis, all members of the Poppy family. Sanguinarine can be obtained by extracting sanguinarine as an active ingredient from plants containing these substances or their salts.

[0053] In the agricultural composition of the present invention, sanguinarine, its derivatives, its salts, or its salts may be blended and dispersed in the temperature-responsive substrate as such, or in the form of a blending agent containing sanguinarine, its derivatives, its salts, or its salts as an active ingredient. Alternatively, sanguinarine, its derivatives, its salts, or its salts may be blended and dispersed in the temperature-responsive substrate by removing the dispersion medium from the blending agent after mixing the blending agent containing sanguinarine, its derivatives, its salts, or its salts as an active ingredient. Examples of blending agents containing sanguinarine, its derivatives, its salts, and / or its salts as active ingredients include Thermozymes (registered trademark) (manufactured by Fujimi Kogyo Co., Ltd.).

[0054] The content of sanguinarine, its derivatives, its salts, and its salts in the agricultural composition of the present invention is not particularly limited and is appropriately selected depending on the environment in which the agricultural composition is used, the type of temperature-responsive substrate, and the like. The content, based on the active ingredient, is preferably 0.00005 to 1.0% by mass, and more preferably 0.0001 to 0.5% by mass. Furthermore, when the agricultural composition of the present invention contains one selected from the group consisting of sanguinarine, its derivatives, its salts, and its salts as a biostimulant, the amount of the active ingredient refers to the content of one such compound. When the composition contains two or more selected from the group consisting of sanguinarine, its derivatives, its salts, and its salts, the amount refers to the total amount of these sanguinarine, its derivatives, its salts, and its salts.

[0055] Examples of biostimulants include choline, alginic acid, fulvic acid, humic acid, and amino acids such as 5-aminolevulinic acid. Fulvic acid, for example, effectively improves plant nutrient absorption. Choline is rapidly absorbed by plants, effectively providing rapid nutrient replenishment. Amino acids activate active soil microorganisms, promote soil granulation, and effectively improve the environment surrounding roots. Examples of commercially available products containing these compounds as active ingredients include RIKIDASU (registered trademark) (manufactured by Hyponex), Morning Fresh (registered trademark) (manufactured by Agro Kanesho), Hi-tac C (registered trademark) (manufactured by Agro Kanesho), Atonik (registered trademark) (manufactured by Asahi Chemical Industries, Ltd.), Livital (registered trademark) (manufactured by OAT Agrio), Fullbody (registered trademark) (manufactured by OAT Agrio), ALA-FeSTA (registered trademark) (manufactured by Sakata Seed Co., Ltd.), Pentakeep (registered trademark) (manufactured by Seiwa Co., Ltd.), Azu-liquid (registered trademark) (manufactured by Denka), Azumin (registered trademark) (manufactured by Denka), BOMBARDIER (registered trademark) (manufactured by Hyponex Japan), PHYTO O2 (registered trademark) (Phytochrome), Tool-dry-soluble (manufactured by Bichemic Japan), Organmin DA (registered trademark) (manufactured by Pulsar International), Diliminosu (registered trademark) (manufactured by Pic-bio), and Royal Humic acid granules (registered trademark) (manufactured by Royal Industries, Ltd.), etc. The content of choline, 5-aminolevulinic acid, alginic acid, fulvic acid, humic acid, and amino acids in the agricultural composition of the present invention is not particularly limited and can be appropriately selected depending on the environment in which the agricultural composition is used, the type of temperature-responsive substrate, and other factors. The content, based on the active ingredient, is preferably 0.00005 to 1.0% by mass, and more preferably 0.0001 to 0.5% by mass. Furthermore, when the agricultural composition of the present invention contains two or more biostimulants, the amount of active ingredient refers to the total amount of these ingredients. In the agricultural composition of the present invention, these biostimulants may be blended and dispersed in the temperature-responsive substrate as such, or in the form of a compounding agent containing these biostimulants as active ingredients. Alternatively, a compounding agent containing these biostimulants as active ingredients may be mixed with the temperature-responsive substrate and then the dispersion medium removed, thereby blending and dispersing these biostimulants in the temperature-responsive substrate.

[0056] Examples of biostimulants include oxidized glutathione, trehalose, and 2-hexenal. Oxidized glutathione, trehalose, and 2-hexenal effectively act to alleviate environmental stress.

[0057] Examples of commercially available biostimulants or formulations containing a biostimulant as an active ingredient include TetsuRiki-Agri (registered trademark) (manufactured by Aichi Steel, Ltd.) and TetsuRiki-Treplus (registered trademark) (manufactured by Aichi Steel, Ltd.), which have iron as an active ingredient; Harmozyme (registered trademark) (manufactured by Arystalifescience, Ltd.), which has a corn extract as an active ingredient; Algamix (registered trademark) (manufactured by OAT Agri, Ltd.) and Kelpak66 (registered trademark) (manufactured by Royal Industries, Ltd.), which have a seaweed extract as an active ingredient; Kaneka Peptide (registered trademark) (manufactured by Kaneka, Ltd.) and Kaneka-Fertilizer (registered trademark) (manufactured by Kaneka, Ltd.), which have oxidized glutathione as an active ingredient; Sannonic (registered trademark) (manufactured by Sanyo Chemical Co., Ltd.), which has a surfactant as an active ingredient; and Oxo-power, which has an oxygen supply agent as an active ingredient. 5 (registered trademark) (manufactured by Takii Seeds and Seedlings Co., Ltd.), MOX (registered trademark) (manufactured by Hodogaya Chemical Co., Ltd.), Neocaroxol (registered trademark) (manufactured by Hodogaya Chemical Co., Ltd.); a compound containing trehalose as the active ingredient (manufactured by Hayashibara Co., Ltd.); Suzumidori (registered trademark) (manufactured by Phytochrome Co., Ltd.) containing 2-hexenal as the active ingredient; Manda 31 (registered trademark) (manufactured by Manda Fermentation Co., Ltd.) containing plant materials as the active ingredient; Agri Revolution (registered trademark) (manufactured by Menicon Co., Ltd.) containing plant cellulase as the active ingredient; and Takii Toreace (registered trademark) (manufactured by Takii Seeds and Seedlings Co., Ltd.) containing trehalose as the active ingredient. The amount of these substances incorporated into the agricultural composition of the present invention is not particularly limited and can be appropriately selected depending on the environment in which the agricultural composition is used, the type of temperature-responsive substrate, and other factors. The amount, based on the active ingredient, is preferably 0.00005 to 1.0% by mass, and more preferably 0.0001 to 0.5% by mass. Furthermore, when the agricultural composition of the present invention contains two or more biostimulants, the amount of the active ingredient refers to the total amount of these substances. In the agricultural composition of the present invention, these biostimulants may be formulated and dispersed in the temperature-responsive substrate by themselves, or in the form of a compounding agent containing these biostimulants as active ingredients, or in the form of a compounding agent containing these biostimulants as active ingredients, after being mixed with the temperature-responsive substrate, the dispersion medium in the compounding agent is removed, thereby formulating and dispersing these biostimulants in the temperature-responsive substrate.

[0058] Examples of biostimulants include microorganisms that contribute to the alleviation of abiotic stress on plants or the promotion of plant growth. The amount of microorganisms incorporated into the agricultural composition of the present invention is not particularly limited and may be appropriately selected depending on the environment in which the agricultural composition is used, the type of temperature-responsive substrate, and the like. The amount, based on the active ingredient, is preferably 0.00005 to 1.0% by mass, and more preferably 0.0001 to 0.5% by mass.

[0059] The content of the biostimulant in the agricultural composition of the present invention is not particularly limited and is appropriately selected depending on the environment in which the agricultural composition is used, the type of temperature-responsive substrate, etc., and is preferably 0.00005 to 1.0% by mass, more preferably 0.0001 to 0.5% by mass, based on the active ingredient, i.e., the biostimulant.

[0060] The agricultural composition of the present invention is composed of a temperature-responsive substrate. In other words, in the agricultural composition of the present invention, the framework is the temperature-responsive substrate.

[0061] In the present invention, the temperature-responsive substrate refers to a material that begins to melt or decompose when the agricultural composition of the present invention is directly applied to a plant or to soil for plant growth and the ambient temperature reaches a predetermined temperature. Furthermore, in the agricultural composition of the present invention, the temperature-responsive substrate forming the agricultural composition begins to melt or decompose when the ambient temperature reaches a predetermined temperature, causing a portion of the temperature-responsive substrate to disintegrate, and the biostimulant contained in the temperature-responsive substrate to be released from the agricultural composition and supplied to the plant or soil.

[0062] The first aspect of the agricultural composition of the present invention is used to impart tolerance to high-temperature stress to plants when subjected to high-temperature stress due to a rise in ambient temperature. In the first aspect of the agricultural composition of the present invention, a temperature-responsive substrate begins to melt or decompose when the ambient temperature rises and reaches a predetermined temperature. In the first aspect of the agricultural composition of the present invention, the temperature at which the release of the biostimulant from the agricultural composition begins, i.e., the predetermined temperature, is the temperature at which the biostimulant must be supplied to the plant in order to impart tolerance to high-temperature stress to the plant. This temperature is appropriately selected based on the type of plant being grown, the environment, the cultivation period, and other factors. For example, if the biostimulant is initiated at a temperature at which the plant cannot grow due to high-temperature stress, there may not be enough time for the plant to develop tolerance. Therefore, the predetermined temperature may be set slightly lower than the temperature at which the plant cannot grow due to high-temperature stress. Furthermore, the first aspect of the agricultural composition of the present invention uses a temperature-responsive substrate that begins to melt or decompose at the predetermined temperature. In other words, in the agricultural composition of the first embodiment of the present invention, a material that does not dissolve or decompose at a temperature lower than a predetermined temperature but begins to dissolve or decompose when the temperature rises and reaches the predetermined temperature is used, and a temperature-responsive substrate whose predetermined temperature is the melting start temperature or a temperature-responsive substrate whose predetermined temperature is the decomposition start temperature is used.

[0063] The second aspect of the agricultural composition of the present invention is used to impart tolerance to cold stress to plants when subjected to low-temperature stress due to a decrease in ambient temperature. In this second aspect of the agricultural composition, when the ambient temperature decreases and reaches a predetermined temperature, the temperature-responsive substrate begins to melt or decompose. In this second aspect of the agricultural composition, the temperature at which the release of the biostimulant from the agricultural composition begins, i.e., the predetermined temperature, is the temperature at which the biostimulant must be supplied to the plant in order to impart tolerance to cold stress to the plant. This temperature is appropriately selected based on the type of plant being grown, the environment, the cultivation period, and other factors. For example, if the biostimulant is initiated at a temperature at which the plant cannot grow due to cold stress, there may not be enough time for the plant to acquire tolerance. Therefore, the predetermined temperature may be set slightly higher than the temperature at which the plant cannot grow due to cold stress. Furthermore, the second aspect of the agricultural composition of the present invention uses a temperature-responsive substrate that begins to melt or decompose at the predetermined temperature. In other words, in the agricultural composition of the second embodiment of the present invention, a material that does not dissolve or decompose at a temperature higher than a predetermined temperature but begins to dissolve or decompose when the temperature is lowered to reach the predetermined temperature is used, and a temperature-responsive substrate whose predetermined temperature is the melting start temperature or a temperature-responsive substrate whose predetermined temperature is the decomposition start temperature is used.

[0064] Examples of temperature-responsive substrates include those that begin to melt at a predetermined temperature. The predetermined temperature, in other words, the melting start temperature of the temperature-responsive substrate, is preferably 0-60°C, more preferably 5-55°C. When growing plants in a high-temperature environment, for example, in a plastic greenhouse in the summer, the temperature inside the greenhouse can sometimes reach 35-45°C. Therefore, when the agricultural composition of the first embodiment of the present invention is used in a high-temperature environment such as a plastic greenhouse in the summer, the predetermined temperature, in other words, the melting start temperature of the temperature-responsive substrate, is preferably 30-60°C, more preferably 35-55°C. Furthermore, when growing plants in a low-temperature environment, for example, in the cultivation of Arabidopsis thaliana, enzyme activity decreases at temperatures of 0-15°C, slowing cellular metabolism. Therefore, when the agricultural composition of the second embodiment of the present invention is used in a low-temperature environment, the predetermined temperature, in other words, the melting start temperature of the temperature-responsive substrate, is preferably 0-20°C, more preferably 5-15°C.

[0065] In the present invention, the melting onset temperature of the temperature-responsive substrate is measured by the test tube inversion method in the following step.

[0066] <In the case of the temperature-responsive substrate according to the first aspect of the agricultural composition of the present invention> Add 5g of the object to be measured to a test tube with a 15mm outer diameter and a 150mm height. Next, place the test tube vertically in hot water and heat it, gradually raising the temperature. While increasing the temperature, visually inspect the flow of the contents by tilting the tube. The temperature at which the object to be measured becomes liquid and flows toward the mouth when the tube is tilted 15 degrees from the vertical is defined as the melting onset temperature.

[0067] <In the case of the temperature-responsive substrate according to the second aspect of the agricultural composition of the present invention> Add 5g of the test object to a test tube with a 15mm outer diameter and a 150mm height. Next, place the test tube vertically in ice water to cool it, gradually lowering the temperature. While lowering the temperature, visually inspect the flow of the contents by tilting the tube. The melting onset temperature is defined as the temperature at which the test object becomes liquid and flows toward the mouth when the tube is tilted 15 degrees from the vertical.

[0068] As materials constituting the temperature-responsive substrate involved in the agricultural composition of the first embodiment of the present invention, grease, hardened oil, and grease containing hardened oil can be listed. As grease, palm oil, soybean oil, coconut oil, coconut oil, olive oil, rapeseed oil, butter, margarine, tallow, chicken fat, and lard can be listed. In addition, as hardened oil, hardened oil obtained by hydrogenating part or all of the unsaturated bonds of greases such as palm oil, soybean oil, coconut oil, coconut oil, olive oil, rapeseed oil, butter, margarine, tallow, chicken fat, and lard can be listed. In addition, as grease containing hardened oil, mixtures of the above-mentioned grease and the above-mentioned hardened oil can be listed. Grease can be one kind or a combination of two or more. In addition, hardened oil can be one kind or a combination of two or more. In addition, grease containing hardened oil can be one kind or a combination of two or more.

[0069] The melting point of the fat, oil, or fat containing hardened oil used for the temperature-responsive substrate of the agricultural composition according to the first aspect of the present invention is preferably 30 to 60°C.

[0070] The types of fats and oils, hardened oils, and fats containing hardened oils used in the temperature-responsive substrate of the agricultural composition according to the first embodiment of the present invention, as well as the mixing ratio of the fats and oils to the hardened oils, are appropriately selected based on the temperature at which the release of the biostimulant from the agricultural composition begins, i.e., the predetermined temperature. In other words, by selecting the types of fats and oils, hardened oils, and fats containing hardened oils used in the temperature-responsive substrate, as well as the mixing ratio of the fats and oils to the hardened oils, the melting start temperature of the temperature-responsive substrate can be adjusted to the predetermined temperature.

[0071] Examples of the material constituting the temperature-responsive substrate of the agricultural composition according to the first aspect of the present invention include gels containing water and a gelling agent.

[0072] Examples of temperature-responsive gelling agents used in the agricultural composition according to the first embodiment of the present invention include proteins such as gelatin and hyaluronic acid. These materials are materials that form a gel by being mixed with water, heated to a gelation temperature, and then cooled to form a gel. The protein used as the gelling agent may be a single protein or a combination of two or more proteins.

[0073] Gelatin is a material obtained by heating and extracting collagen, the main component of animal skin, bones, tendons, and other materials. While there are no particular restrictions on the production method, examples of gelatin include materials produced by heating and extracting crude collagen obtained from the skin, bones, and tendons of cattle, pigs, chickens, and fish, treated with acids or alkalis. Gelatin can also be hydrolyzed, oxygen-decomposed, or gelatin derivatives (e.g., acylated gelatin).

[0074] The type of protein used as a gelling agent for the temperature-responsive substrate of the agricultural composition according to the first embodiment of the present invention, and the combination and mixing ratio of two or more proteins when used, are appropriately selected based on the temperature at which the release of the biostimulant from the agricultural composition begins, i.e., the predetermined temperature. In other words, the melting onset temperature of the temperature-responsive substrate can be adjusted to the predetermined temperature by selecting the type of protein used as a gelling agent, and the combination and mixing ratio of two or more proteins when used.

[0075] Examples of the temperature-responsive gelling agent used in the agricultural composition according to the first embodiment of the present invention include thickening polysaccharides such as locust bean gum, xanthan gum, carrageenan, agar, tara gum, gellan gum, and pectin. Examples thereof include materials that form a gel by being mixed with water, heated to a gelling temperature, and then cooled to form a gel. The thickening polysaccharide used as the gelling agent may be a single type or a combination of two or more types.

[0076] The type of thickening polysaccharide used as a gelling agent for the temperature-responsive substrate of the agricultural composition according to the first embodiment of the present invention, and the combination and mixing ratio of two or more thickening polysaccharides when used, are appropriately selected based on the temperature at which the release of the biostimulant from the agricultural composition begins, i.e., the predetermined temperature. In other words, the melting onset temperature of the temperature-responsive substrate can be adjusted to the predetermined temperature by selecting the type of thickening polysaccharide used as a gelling agent, and the combination and mixing ratio of two or more thickening polysaccharides when used.

[0077] The temperature-responsive gelling agent used in the agricultural composition according to the first embodiment of the present invention is a mixture of one or more proteins such as gelatin and hyaluronic acid and one or more thickening polysaccharides such as locust bean gum, xanthan gum, carrageenan, agar, tara gum, gellan gum, and pectin. Examples of such materials include those that form a gel by being mixed with water, heated to a gelation temperature, and then cooled to gel.

[0078] When a mixture of a protein and a thickening polysaccharide is used as a gelling agent for the temperature-responsive base involved in the first embodiment of the agricultural composition of the present invention, the melting onset temperature of the temperature-responsive base can be adjusted to a predetermined temperature by selecting the type of protein, the type of thickening polysaccharide, and their mixing ratio. Therefore, the use of a mixture of a protein and a thickening polysaccharide as a gelling agent is preferred in terms of easy adjustment of the melting onset temperature of the temperature-responsive base.

[0079] The type of protein and thickening polysaccharide used as the gelling agent for the temperature-responsive substrate of the agricultural composition according to the first embodiment of the present invention, and their mixing ratio are appropriately selected according to the temperature at which the release of the biostimulant from the agricultural composition begins, that is, the predetermined temperature.

[0080] The water content in the gel for the temperature-responsive substrate according to the first embodiment of the agricultural composition of the present invention is appropriately selected and is, for example, 0.10 to 10.0% by mass.

[0081] Examples of the material constituting the temperature-responsive substrate of the agricultural composition according to the second embodiment of the present invention include gels containing water and a gelling agent.

[0082] The temperature-responsive gelling agent used in the agricultural composition according to the second embodiment of the present invention is one or more thickening polysaccharides such as methylcellulose and hydroxypropylmethylcellulose. Examples of such gelling agents include those that dissolve when mixed with heated water and cooled, and then form a gel when the temperature rises. The thickening polysaccharide used as the gelling agent may be a single type or a combination of two or more types.

[0083] The type of material constituting the temperature-responsive substrate involved in the agricultural composition according to the second embodiment of the present invention, and the mixing ratio of these materials when multiple materials are used, are appropriately selected based on the temperature at which the release of the biostimulant from the agricultural composition begins, i.e., the predetermined temperature. In other words, by selecting the type of material constituting the temperature-responsive substrate and the mixing ratio of these materials when multiple materials are used, the melting start temperature of the temperature-responsive substrate can be adjusted to the predetermined temperature.

[0084] The water content in the gel for the temperature-responsive substrate according to the second embodiment of the agricultural composition of the present invention is appropriately selected and is, for example, 0.10 to 10.0% by mass.

[0085] Examples of temperature-responsive substrates include those that begin to decompose at a predetermined temperature. In the present invention, initiation of decomposition means that a portion of the compound comprising the temperature-responsive substrate begins to decompose when the ambient temperature reaches a predetermined temperature. The predetermined temperature, in other words, the decomposition start temperature of the temperature-responsive substrate is preferably 0-60°C, more preferably 5-55°C. When plants are cultivated in a high-temperature environment, for example, in a plastic greenhouse in the summer, the temperature inside the greenhouse can sometimes reach 35-45°C. Therefore, when the agricultural composition of the first embodiment of the present invention is used in a high-temperature environment such as a plastic greenhouse in the summer, the predetermined temperature, in other words, the decomposition start temperature of the temperature-responsive substrate is preferably 30-60°C, more preferably 35-55°C. Furthermore, when plants are cultivated in a low-temperature environment, for example, in the cultivation of Arabidopsis thaliana, enzyme activity decreases at temperatures of 0-15°C, slowing cellular metabolism. Therefore, when the agricultural composition of the second embodiment of the present invention is used in a low-temperature environment, the predetermined temperature, in other words, the decomposition start temperature of the temperature-responsive substrate is preferably 0-20°C, more preferably 5-15°C.

[0086] The agricultural composition of the present invention may contain a spreading agent. The spreading agent has the function of enhancing the wettability, adhesion, spreadability, and drapeability of the agricultural composition, thereby ensuring uniform adhesion of the agricultural composition. In particular, when the agricultural composition of the present invention is sprayed directly onto plants to adhere directly to the leaves, stems, etc. of the plants, the agricultural composition of the present invention is adhered to the plants by spraying a dispersion prepared by dispersing the agricultural composition of the present invention in an aqueous solvent onto the plants. The spreading agent is used to ensure uniform adhesion of the agricultural composition of the present invention to the plant surface at an appropriate density when the dispersion containing the agricultural composition of the present invention is sprayed onto the plants.

[0087] As the spreading agent, there is no particular limitation as long as it can be used in agriculture, and examples include nonionic surfactants, for example, materials with polyoxyethylene alkylphenyl ether-based surfactants, polyoxyethylene alkyl ether-based surfactants, polyalkylene glycol alkyl ether-based surfactants, polyoxyethylene fatty acid ester-based surfactants, polyoxyethylene resin acid ester-based surfactants, polyoxyethylene hexitol anhydride fatty acid ester-based surfactants, sorbitan fatty acid ester-based surfactants, silicone-based surfactants, etc. as active ingredients; anionic surfactants, for example, materials with naphthylmethane sulfonate-based surfactants, lignin sulfonate-based surfactants, alkyl sulfosuccinate-based surfactants as active ingredients; cationic surfactants, for example, tetraalkylammonium salt-based surfactants, etc. Examples of commercially available spreaders include Approach BI (registered trademark, manufactured by Maruwa Biochemical Co., Ltd.), Skasyu (registered trademark, manufactured by Maruwa Biochemical Co., Ltd.), Surfactant WK (registered trademark, manufactured by Maruwa Biochemical Co., Ltd.), Mixpower (registered trademark, manufactured by Syngenta Japan Co., Ltd.), and Supply (registered trademark, manufactured by OAT Agrio Co., Ltd.).

[0088] The content of the spreader in the agricultural composition of the present invention is appropriately selected, and is, for example, 0.10 to 40.0% by mass, preferably 0.10 to 25.0% by mass, and more preferably 1.0 to 20.0% by mass.

[0089] The agricultural composition of the present invention may contain a conditioner, a solvent, an emulsifier, a preservative, an antioxidant, a fragrance, a dye, a pigment, a stabilizer, and the like as needed.

[0090] The size of the agricultural composition of the present invention is not particularly limited and may be appropriately selected depending on the method of use. For example, when spraying a granular material (solid) onto soil for plant growth, the agricultural composition of the present invention preferably has an average particle size of 0.001 to 5.0 mm, more preferably 0.01 to 1.0 mm, for ease of handling. Furthermore, when the agricultural composition of the present invention is dispersed in an aqueous agricultural dispersion containing an aqueous solvent and then directly sprayed onto plants to adhere to the leaves or stems of the plants, the average particle size of the agricultural composition of the present invention is preferably 0.001 to 5.0 mm, more preferably 0.01 to 1.0 mm, for improved uniformity and adhesion. The above average particle size is illustrative based on examples of methods of use and the size of the agricultural composition of the present invention is not limited thereby.

[0091] The method for producing the agricultural composition of the first embodiment of the present invention is not particularly limited. For example, the following methods can be mentioned: dissolving or dispersing a biostimulant in water, heating the liquid containing the obtained biostimulant, adding a gelling agent thereto, stirring and mixing, and then cooling to gel, thereby producing the agricultural composition of the present invention; heating and melting fats, hardened oils, or fats and oils containing hardened oils, adding a biostimulant thereto, stirring and mixing, and then cooling, thereby producing the agricultural composition of the present invention.

[0092] The method for producing the agricultural composition of the second embodiment of the present invention is not particularly limited. For example, the following method can be used: dissolving or dispersing a biostimulant in water, heating the liquid containing the obtained biostimulant, adding a gelling agent thereto, stirring and mixing, cooling to dissolve, and then heating to gel, thereby producing the agricultural composition of the present invention.

[0093] In addition, as a method for producing the agricultural composition of the present invention, the following method can be mentioned: a temperature-responsive material that starts to decompose at a decomposition starting temperature and a biostimulant are dissolved or dispersed in a solvent, formed into a paste or clay form, and then granulated to produce the agricultural composition of the present invention.

[0094] The agricultural composition of the present invention can be sprayed directly onto the plants or onto the soil in which the plants grow before the ambient temperature reaches a temperature at which the plants are stressed, when stress is applied to the plants due to changes in ambient temperature during plant cultivation. When the ambient temperature changes and reaches "a temperature at which a biostimulant needs to be supplied to the plants in order to impart tolerance to stress caused by temperature changes to the plants," that is, when the ambient temperature reaches a predetermined temperature, the temperature-responsive substrate constituting the agricultural composition of the present invention begins to melt or decompose, and the biostimulant is supplied from the agricultural composition of the present invention.

[0095] According to the first embodiment of the agricultural composition of the present invention, if the agricultural composition of the first embodiment of the present invention is sprayed directly onto plants or onto soil in which plants are grown before a date when the environmental temperature is predicted to reach a temperature that causes high temperature stress, when the environmental temperature reaches "a temperature at which a biostimulant needs to be supplied to plants in order to impart tolerance to high temperature stress to plants," that is, when the environmental temperature reaches a predetermined temperature, the temperature-responsive substrate constituting the agricultural composition of the first embodiment of the present invention begins to melt or decompose, and the biostimulant can be supplied from the agricultural composition of the first embodiment of the present invention. Therefore, the biostimulant can be supplied to the plants promptly when needed.

[0096] Furthermore, although the agricultural composition of the first embodiment of the present invention is sprayed directly onto plants or onto the soil in which the plants grow before the date when the ambient temperature is predicted to be high temperature stress, contrary to expectations, thereafter, a period of time continues when the ambient temperature is not higher than the level at which the plants will be subjected to high temperature stress. Since the temperature-responsive substrate constituting the agricultural composition of the first embodiment of the present invention does not begin to melt or decompose until the ambient temperature reaches "the temperature at which the biostimulant needs to be supplied to the plants in order to impart tolerance to high temperature stress to the plants", that is, the predetermined temperature, the biostimulant is not released from the agricultural composition of the first embodiment of the present invention. Therefore, even if the agricultural composition of the first embodiment of the present invention is sprayed too early, the biostimulant is not wasted.

[0097] In summer greenhouse cultivation, the maximum temperature rises over time. As time goes by, the temperature inside the greenhouse becomes higher and higher. At a certain point, it reaches a temperature at which plants cannot tolerate high temperature stress. Therefore, before such weather occurs, cultivation in the greenhouse for that season has to be stopped. However, since it is difficult to accurately predict the weather in summer, the following situations may occur: (1) The date when the temperature at which plants cannot tolerate high temperature stress is predicted to be approaching, and cultivation for that season is abandoned in advance. However, the date when the temperature at which plants cannot tolerate high temperature stress actually reaches the date later than expected. As a result of subsequent analysis, cultivation and harvesting can be resumed. On the contrary, (2) There is enough time before the date when the temperature at which plants cannot tolerate high temperature stress is predicted to reach the date, and cultivation is resumed. However, the date when the temperature at which plants cannot tolerate high temperature stress actually reaches the date earlier than expected. Therefore, the plants cannot grow due to high temperature stress before harvesting, and harvesting cannot be carried out. In addition, the following situations may occur: (3) When spraying a biostimulant to impart tolerance to high temperature stress to plants, the biostimulant is sprayed multiple times for safety, but the result of subsequent analysis shows that the biostimulant spraying is actually only the last time, and the previous spraying of the biostimulant is wasted. In response to the above problem, if the agricultural composition of the first embodiment of the present invention is sprayed directly on the plants in the plastic greenhouse or on the soil for plant growth in advance, the temperature in the plastic greenhouse increases with the rise in air temperature. When the temperature in the plastic greenhouse reaches "the temperature at which the biostimulant needs to be supplied to the plants in order to impart tolerance to high temperature stress to the plants", that is, when it reaches the predetermined temperature, the temperature-responsive substrate constituting the agricultural composition of the first embodiment of the present invention begins to melt or decompose, and the biostimulant can be supplied from the agricultural composition of the first embodiment of the present invention. Therefore, in greenhouse cultivation in summer, the biostimulant can be supplied to the plants in a timely and rapid manner by spraying in advance once when it is needed. Therefore, according to the agricultural composition of the first embodiment of the present invention, greenhouse cultivation in summer can be carried out efficiently.

[0098] According to the second embodiment of the agricultural composition of the present invention, if the second embodiment of the agricultural composition of the present invention is sprayed directly onto plants or onto soil for plant growth before a date when the environmental temperature is predicted to reach a temperature that causes low temperature stress, when the environmental temperature reaches "a temperature at which a biostimulant needs to be supplied to the plants in order to impart tolerance to low temperature stress to the plants", that is, when the environmental temperature reaches a predetermined temperature, the temperature-responsive substrate constituting the second embodiment of the agricultural composition of the present invention begins to melt or decompose, and the biostimulant can be supplied from the second embodiment of the agricultural composition of the present invention, thereby enabling the biostimulant to be supplied to the plants promptly when needed.

[0099] In addition, although the agricultural composition of the second embodiment of the present invention is sprayed directly onto plants or onto the soil for plant growth before the date when the environmental temperature is predicted to reach a level that causes low temperature stress, contrary to expectations, the environmental temperature temporarily continues for a period of time at or above the level at which the plants will be subjected to low temperature stress. Since the temperature-responsive substrate constituting the agricultural composition of the second embodiment of the present invention does not begin to melt or decompose until the environmental temperature reaches "the temperature at which the biostimulant needs to be supplied to the plants in order to impart tolerance to low temperature stress to the plants", that is, the predetermined temperature, the biostimulant is not released from the agricultural composition of the second embodiment of the present invention. Therefore, even if the agricultural composition of the second embodiment of the present invention is sprayed too early, the biostimulant is not wasted.

[0100] It is known that in the cultivation of legumes, such as soybeans, the appropriate growth temperature is around 25°C, and the yield decreases when the temperature remains low. For example, biostimulants are effective in improving the yield when the temperature drops sharply during cultivation from summer to autumn. However, it is difficult to accurately predict the weather, so the following situations may occur: (1) It is predicted that there will be enough time until the date when the temperature reaches a point where the plants cannot tolerate low temperature stress, and the cultivation is carried out without spraying biostimulants. However, the date when the temperature reaches a point where the plants are subjected to low temperature stress is actually reached contrary to the expectation, and the yield decreases due to low temperature stress before the harvest. In addition, the following situations may occur: (2) When spraying biostimulants to impart tolerance to low temperature stress to plants, the biostimulant is sprayed multiple times for safety reasons, but the results of subsequent analysis show that the biostimulant spraying is actually only needed on the last occasion, and the biostimulant spraying before that is wasted. To address the above problem, if the agricultural composition of the second embodiment of the present invention is sprayed directly onto soybean plants or onto the soil in which the plants grow, as the ambient temperature decreases with the air temperature, the temperature of the environment decreases. When the ambient temperature reaches "a temperature at which a biostimulant needs to be supplied to the plants in order to impart tolerance to low temperature stress to the plants," that is, a predetermined temperature, the temperature-responsive substrate constituting the agricultural composition of the second embodiment of the present invention begins to melt or decompose, enabling the supply of the biostimulant from the agricultural composition of the second embodiment of the present invention. Therefore, during soybean cultivation, the biostimulant can be supplied promptly and quickly to the plants through a single, pre-sprayed application. Therefore, the agricultural composition of the second embodiment of the present invention enables efficient soybean cultivation.

[0101] In land where the air temperature reaches a temperature at which plants cannot tolerate high-temperature stress or where plants cannot tolerate low-temperature stress, if the agricultural composition of the first aspect of the present invention or the agricultural composition of the second aspect of the present invention is sprayed directly onto the plants or onto the soil where the plants grow, when the air temperature rises and reaches the "temperature at which the biostimulant needs to be supplied to the plants in order to impart tolerance to high-temperature stress to the plants," or when the air temperature drops and reaches the "temperature at which the biostimulant needs to be supplied to the plants in order to impart tolerance to low-temperature stress to the plants," that is, when the predetermined temperature is reached, the temperature-responsive substrate constituting the agricultural composition of the first aspect of the present invention or the agricultural composition of the second aspect of the present invention begins to melt or decompose, and the biostimulant can be supplied from the agricultural composition of the first aspect of the present invention or the agricultural composition of the second aspect of the present invention. Therefore, the agricultural composition of the first aspect of the present invention or the agricultural composition of the second aspect of the present invention can be sprayed over the entire land in advance, and the biostimulant can be supplied to the plants promptly when it is needed. Therefore, even if the land area is large or there are sudden changes in weather, the biostimulant can be supplied to the plants promptly when it is needed. On the other hand, when the biostimulant is directly sprayed on the land where the temperature reaches a temperature at which the plants cannot tolerate high temperature stress or a temperature at which the plants cannot tolerate low temperature stress, if the land area is too large or there are sudden changes in the weather, there will not be enough time to supply the biostimulant to the plants.

[0102] Examples of methods for using the agricultural composition of the present invention include forming the agricultural composition of the present invention into granules and spraying the granular agricultural composition of the present invention onto soil for plant growth. When the granular agricultural composition of the present invention is sprayed onto soil for plant growth, the average particle size of the agricultural composition of the present invention is not particularly limited, but is preferably 0.001 to 5.0 mm, more preferably 0.01 to 1.0 mm, for ease of handling.

[0103] Examples of methods for using the agricultural composition of the present invention include a method in which the agricultural composition of the present invention is formed, pressure is applied, and sprayed to form a fine solid substance on soil for plant growth.

[0104] Examples of methods for using the agricultural composition of the present invention include dispersing the agricultural composition of the present invention in an aqueous solvent and spraying the resulting dispersion directly onto plants, thereby causing the agricultural composition of the present invention to adhere to the surfaces of leaves, stems, etc. of the plants. This method is characterized in that when the agricultural composition of the present invention dispersed in an aqueous solvent is sprayed directly onto plants, the dispersion to be sprayed, i.e., the aqueous agricultural dispersion of the present invention, contains the agricultural composition of the present invention, and the agricultural composition of the present invention is dispersed in the aqueous solvent.

[0105] The agricultural composition of the present invention contained in the aqueous dispersion for agricultural use of the present invention preferably contains 0.10 to 40.0% by mass of a spreader, more preferably 0.10 to 25.0% by mass of a spreader, and even more preferably 1.0 to 20.0% by mass of a spreader. By containing the spreader in the above-described range, the agricultural composition of the present invention contained in the aqueous dispersion for agricultural use of the present invention can be directly sprayed onto plants, allowing the agricultural composition of the present invention contained therein to adhere uniformly to the surface of the plant at an appropriate density.

[0106] The average particle size of the agricultural composition of the present invention contained in the aqueous dispersion for agricultural use of the present invention is not particularly limited as long as it is a size that can be dispersed in an aqueous solvent, but is preferably 0.001 to 5.0 mm, more preferably 0.01 to 1.0 mm. By setting the average particle size of the agricultural composition of the present invention contained in the aqueous dispersion for agricultural use of the present invention within this range, uniform spraying can be achieved.

[0107] The aqueous solvent used in the agricultural aqueous dispersion of the present invention includes water, a mixed solvent of water and an aqueous alcohol, etc. Examples of the aqueous alcohol used in the aqueous solvent include methanol, ethanol, isopropyl alcohol, glycols, etc.

[0108] The content of the agricultural composition of the present invention in the aqueous dispersion for agriculture of the present invention is not particularly limited, but is, for example, 0.05 to 10.0% by mass, preferably 0.1 to 1.0% by mass.

[0109] The agricultural aqueous dispersion of the present invention may contain a regulator, a solvent, an emulsifier, a preservative, an antioxidant, a fragrance, a dye, a pigment, a stabilizer, and the like, as needed.

[0110] Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to the examples shown below.

[0111] Example Hereinafter, the agricultural composition of the present invention will be described with reference to Examples, but the present invention is not limited to these embodiments.

[0112] (Example 1) A biostimulant solution containing 1 gram of zingerone solution (0.10 mass %) was added to 99 grams of water. The resulting solution was then heated to 60°C, and 2.5 mass % of gelatin was added relative to the mass of the solution. After stirring and mixing, the mixture was cooled to 0°C. After cooling at 0°C for 6 hours, a solidified gel was obtained. The biostimulant content in the resulting gel was 0.001 mass %.

[0113] Next, the melting onset temperature of the obtained gel was measured by the following measurement method. As a result, the melting onset temperature of the obtained gel was 28°C.

[0114] Next, a verification test against high temperature stress was conducted using the obtained gel according to the following test method. The results are shown in Tables 1 and 2.

[0115] <Method for measuring melting onset temperature> 5 g of the object to be measured was placed in a test tube with a 15 mm outer diameter and a 150 mm height. The test tube containing the object to be measured was then placed vertically in hot water and heated to increase the temperature of the test tube. While the temperature was increasing, the test tube was tilted visually to confirm the flow of the contents. The temperature at which the object to be measured became liquid and flowed toward the mouth when the test tube was tilted 15 degrees from the vertical was defined as the melting onset temperature.

[0116] <Verification test 1 against high temperature stress> Four samples were prepared by adding seedling soil to 15 cm pots and adjusting the soil pH to 6.0-6.5. After fertilizer was buried in the soil of each of the four pots, one was sprayed with the test substance, one was sprayed with water, and the remaining two were sprayed with a 0.10% by mass solution of zingerone. These were the test substance spray tank, water spray tank, zingerone spray tank 1, and zingerone spray tank 2.

[0117] Next, the komatsuna were left standing for one week in an environment at 23°C, sprayed with water regularly, and then grown to the point where the main leaves had expanded, and then transferred to four pots respectively.

[0118] Next, the four tanks were transferred to an environment of 35° C. At this time, the zingerone spray tank 2 was sprayed again with a 0.10 mass % zingerone solution.

[0119] Then, after being left in an environment at 35°C for one week, the growth status was checked. The results are shown in Table 1.

[0120] (Evaluation Criteria) 0:Growth confirmed in all △: Some of the cells showed poor growth or no growth. ×: No growth was confirmed at all [Table 1]

[0121] In Table 1, A refers to the test object spray tank, B refers to the water spray tank, C refers to the zingerone spray tank 1, and D refers to the zingerone spray tank 2.

[0122] <Verification test 2 against high temperature stress> Four samples were prepared by placing seedling soil in 15 cm pots and adjusting the soil pH to 6.0-6.5. After burying fertilizer in the soil of each of the four pots, one was sprayed with the test substance, one was sprayed with water, and the remaining two were sprayed with a 0.10% by mass solution of zingerone. These were the test substance spray tank, water spray tank, zingerone spray tank 1, and zingerone spray tank 2.

[0123] After being left for one week at 23°C with regular watering, leaf lettuce was sown on a seedling-raising sponge laid on a seedling-raising tray and germinated and transferred to four pots.

[0124] Next, the four tanks were transferred to an environment of 35° C. At this time, the zingerone spray tank 2 was sprayed again with a 0.10 mass % zingerone solution.

[0125] Then, after being left in an environment at 35°C for one week, the growth status was checked. The results are shown in Table 2.

[0126] [Table 2]

[0127] In Table 2, A refers to the test object spray tank, B refers to the water spray tank, C refers to the zingerone spray tank 1, and D refers to the zingerone spray tank 2.

[0128] (Examples 2 to 6) A gel was obtained in the same manner as in Example 1 except that gelatin and the thickening polysaccharide shown in Table 3 were added to give a total of 2.5 mass % based on the mass of the solution instead of 2.5 mass % of gelatin based on the mass of the solution.

[0129] Next, the melting onset temperature of the obtained gel was measured by the same measurement method as in Example 1. The results are shown in Table 3.

[0130] [Table 3]

[0131] According to Table 3, it was confirmed that the gels of Examples 2 to 6 began to melt at the melting start temperatures in Table 3. Therefore, it is speculated that if the melting start temperatures of the gels of Examples 2 to 6 are set to a predetermined temperature, the biostimulant can be released at the predetermined temperature.

[0132] (Example 7) 100 g of palm oil (trade name Carotino, manufactured by Carotino) was heated to 50°C, 0.1 g of a biostimulant (0.10 mass % zingerone solution) was added, and the mixture was stirred for 10 minutes before being cooled to 0°C to obtain a solid. The biostimulant content in the obtained solid was 0.001 mass %.

[0133] Next, the melting onset temperature of the obtained solid material was measured by the same measurement method as in Example 1. As a result, the melting onset temperature of the obtained solid material was 38°C.

[0134] Next, using the obtained solid matter, a verification test 2 against high temperature stress was carried out by the same test method as in Example 1. The results are shown in Table 4.

[0135] [Table 4]

[0136] In Table 4, A refers to the test object spray tank, B refers to the water spray tank, C refers to the zingerone spray tank 1, and D refers to the zingerone spray tank 2.

Claims

1. An agricultural composition, characterized in that The agricultural composition is composed of a temperature-responsive base material that begins to melt or decompose at a predetermined temperature. The agricultural composition includes a biostimulant that alleviates abiotic stress on plants or promotes plant growth.

2. The agricultural composition according to claim 1, wherein The temperature-responsive substrate is a material that does not dissolve or decompose at a temperature lower than the predetermined temperature and begins to dissolve or decompose when the temperature rises and reaches the predetermined temperature. The melting start temperature or decomposition start temperature of the temperature-responsive substrate is 30-60°C.

3. The agricultural composition according to claim 1, wherein The temperature-responsive substrate is a material that does not dissolve or decompose at a temperature higher than the predetermined temperature, but begins to dissolve or decompose when the temperature decreases and reaches the predetermined temperature. The melting start temperature or decomposition start temperature of the temperature-responsive substrate is 0-20°C.

4. The agricultural composition according to any one of claims 1 to 3, characterized in that The biostimulant is a compound that induces heat shock proteins.

5. The agricultural composition according to any one of claims 1 to 3, characterized in that The temperature-responsive substrate is composed of a gel containing water and a gelling agent.

6. An aqueous dispersion for agricultural use, characterized in that The agricultural aqueous dispersion comprises the agricultural composition according to any one of claims 1 to 3, The agricultural composition is dispersed in an aqueous solvent.

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