Method for inducing high-temperature stress tolerance in plants

Abstract

The present invention addresses the problem of providing a technique for inducing high-temperature stress tolerance in a plant. According to the present invention, high-temperature stress tolerance in plants is induced by using, in combination, a substance having properties for changing the metabolism of plants with respect to amino acids such as valine and a substance having auxin-like activity such as indole-3-acetic acid.

Description

Method for inducing high temperature stress tolerance in plants

[0001] The present invention relates to a technique for inducing high temperature stress tolerance in plants.

[0002] Substances that have the property of altering amino acid metabolism in plants (e.g., branched-chain amino acids such as valine and related compounds) are known to have the function of inducing high temperature stress tolerance in plants (Patent Document 1).

[0003] Auxins such as indole-3-acetic acid (IAA) are known to have the function of reversing high temperature-induced male sterility in plants (Non-Patent Document 1).

[0004] Patent Publication No. 2012-197249

[0005] Tadashi Sakata et al. Auxins reverse plant male sterility caused by high temperatures. Proc Natl Acad Sci US A. 2010 May 11;107(19):8569-74.

[0006] An objective of the present invention is to provide a technique for inducing high temperature stress tolerance in plants.

[0007] As a result of intensive research to solve the above-mentioned problems, the inventors discovered that by applying to plants a substance that has the property of altering the amino acid metabolism of plants, such as valine, in combination with a substance that has auxin-like activity, such as IAA, it is possible to significantly induce high temperature stress tolerance in plants, and thus completed the present invention.

[0008] That is, the present invention can be exemplified as follows: [1] A composition for inducing high temperature stress tolerance in plants, comprising the following components (A) and (B): (A) a substance having the property of altering amino acid metabolism in plants; (B) a substance having auxin-like activity. [2] The composition, wherein the component (A) is the following components (A1), (A2), (A3), or a combination thereof: (A1) one or more components selected from the group consisting of branched-chain amino acids and intermediates in their biosynthetic and consumption pathways; (A2) a substance having inhibitory activity against acetolactate synthase; (A3) a substance having inhibitory activity against 5-enolpyruvylshikimate-3-phosphate synthase. [3] The composition, wherein the component (A1) is one or more components selected from the group consisting of pyruvic acid, ketobutyric acid, acetolactic acid, acetohydroxybutyric acid, 2,3-dihydroxyisovaleric acid, 2,3-dihydroxy-3-methylvaleric acid, α-ketoisovaleric acid, ketomethylvaleric acid, 2-isopropylmalic acid, 3-isopropylmalic acid, ketoisocaproic acid, valine, leucine, isoleucine, and derivatives thereof. [4] The composition, wherein the component (A1) is one or more components selected from the group consisting of valine, leucine, and α-ketoisovaleric acid. [5] The composition, wherein the branched-chain amino acid is in the L-configuration. [6] The composition, wherein component (A2) is one or more components selected from the group consisting of sulfonylurea compounds, imidazoline compounds, pyrimidinyl salicylic acid compounds, triazolopyrimidine sulfonamide compounds, pyrimidinyl(thio)benzoates, sulfonanilide compounds, and sulfonylaminocarbonyltriazolinone compounds. [7] The composition, wherein component (A3) is glyphosate. [8] The composition, wherein component (B) is one or more components selected from the group consisting of indole-3-acetic acid, 4-chloroindole-3-acetic acid, 2,4-dichlorophenoxyacetic acid, 2,4,5-trichlorophenoxyacetic acid, naphthaleneacetic acid, naphthoxyacetic acid, phenylacetic acid, and analogs thereof.[9] The composition, wherein the component (B) is one or more components selected from the group consisting of indole-3-acetic acid and phenylacetic acid.

[10] The composition, wherein the component (A1) is used in a liquid form containing a concentration of 200 μM to 200 mM.

[11] The composition, wherein the component (A2) is used in a liquid form containing a concentration of 5 nM to 5 μM.

[12] The composition, wherein the component (A3) is used in a liquid form containing a concentration of 500 nM to 100 μM.

[13] The composition, wherein the component (B) is used in a liquid form containing a concentration of 500 nM to 500 μM.

[14] The composition, wherein the induction of high temperature stress tolerance is the alleviation of high temperature stress symptoms.

[15] The composition, wherein the alleviation of high temperature stress symptoms is an increase in plant yield.

[16] The composition, wherein the plant is a grass, a solanaceae, a cucurbit, a legume, a Brassicaceae, a rose, a moraceae, a mallow, a pipal, a lily, a asteraceae, a amaranthaceae, an ericaceae, a vitiaceae, a citrus, a rubiaceae, an oleaceae, a laurel, a anacardiaceae, a Sapindaceae, or a Lamiaceae plant.

[17] A method for inducing high temperature stress tolerance in a plant, the method comprising applying to the plant the following components (A) and (B): (A) a substance having the property of altering amino acid metabolism in plants; (B) a substance having auxin-like activity.

[18] A method for producing a plant, comprising applying the following components (A) and (B) to the plant and cultivating the plant; and harvesting the plant: (A) a substance having a property of altering amino acid metabolism in the plant; (B) a substance having auxin-like activity.

[19] The method, wherein the component (A) is the following components (A1), (A2), (A3), or a combination thereof: (A1) one or more components selected from the group consisting of branched-chain amino acids and intermediates in their biosynthetic pathways and consumption pathways; (A2) a substance having inhibitory activity against acetolactate synthase; (A3) a substance having inhibitory activity against 5-enolpyruvylshikimate-3-phosphate synthase.

[20] The method as described above, wherein the component (A1) is one or more components selected from the group consisting of pyruvic acid, ketobutyric acid, acetolactic acid, acetohydroxybutyric acid, 2,3-dihydroxyisovaleric acid, 2,3-dihydroxy-3-methylvaleric acid, α-ketoisovaleric acid, ketomethylvaleric acid, 2-isopropylmalic acid, 3-isopropylmalic acid, ketoisocaproic acid, valine, leucine, isoleucine, and derivatives thereof.

[21] The method as described above, wherein the component (A1) is one or more components selected from the group consisting of valine, leucine, and α-ketoisovaleric acid.

[22] The method as described above, wherein the branched-chain amino acid is in the L-configuration.

[23] The method described above, wherein component (A2) is one or more components selected from the group consisting of sulfonylurea compounds, imidazoline compounds, pyrimidinyl salicylic acid compounds, triazolopyrimidine sulfonamide compounds, pyrimidinyl(thio)benzoates, sulfonanilide compounds, and sulfonylaminocarbonyltriazolinone compounds.

[24] The method described above, wherein component (A3) is glyphosate.

[25] The method described above, wherein component (B) is one or more components selected from the group consisting of indole-3-acetic acid, 4-chloroindole-3-acetic acid, 2,4-dichlorophenoxyacetic acid, 2,4,5-trichlorophenoxyacetic acid, naphthaleneacetic acid, naphthoxyacetic acid, phenylacetic acid, and analogs thereof.

[26] The method described above, wherein component (B) is one or more components selected from the group consisting of indole-3-acetic acid and phenylacetic acid.

[27] The method described above, wherein the component (A1) is used in the form of a liquid containing the component (A1) at a concentration of 200 μM to 200 mM.

[28] The method described above, wherein the component (A2) is used in the form of a liquid containing the component (A2) at a concentration of 5 nM to 5 μM.

[29] The method described above, wherein the component (A3) is used in the form of a liquid containing the component (A3) at a concentration of 500 nM to 100 μM.

[30] The method described above, wherein the component (B) is used in the form of a liquid containing the component (B) at a concentration of 500 nM to 500 μM.

[31] The method described above, wherein the induction of high temperature stress tolerance is the alleviation of high temperature stress symptoms.

[32] The method as described above, wherein the alleviation of high temperature stress symptoms is an increase in plant yield.

[33] The method as described above, wherein the plant is a grass, a solanaceae, a cucurbit, a legume, a Brassicaceae, a rose, a mulberry, a mallow, a pipal, a lily, a aster, a amaranth, a rhododendron, a vitiaceae, a citrus, a rubiaceae, a oleaceae, a laurel, a saccharaceae, a Sapindaceae, or a Lamiaceae plant.

[0009] According to the present invention, high temperature stress tolerance can be induced in plants.

[0010] 6(a) and 6(b) show the results of evaluating high temperature stress tolerance genes in tomatoes treated with high temperature stress and Val and / or PAA. (a) and (b) show the results of evaluating high temperature stress tolerance genes in tomatoes treated with high temperature stress and Val and / or PAA. (b) and (c) show the results of evaluating high temperature stress tolerance genes in tomatoes treated with high temperature stress and Val and / or PAA. (c) and (d) show the results of evaluating high temperature stress tolerance genes in tomatoes treated with high temperature stress and Val and / or PAA. (c) and (d) show the results of evaluating high temperature stress tolerance genes in tomatoes treated with high temperature stress and Val and / or PAA. (d) and (c) show the results of evaluating high temperature stress tolerance genes in tomatoes treated with high temperature stress and Val and / or PAA. (e) and (c) show the results of evaluating high temperature stress tolerance genes in tomatoes treated with high temperature stress and Val and / or PAA. (e) and (c) show the results of evaluating high temperature stress tolerance genes in tomatoes treated with high temperature stress and Val and / or PAA. (f) and (c) show the results of evaluating high temperature stress tolerance genes in tomatoes treated with high temperature stress and Val and / or PAA. (g) and (h) show the results of evaluating high temperature stress tolerance genes in tomatoes treated with high temperature stress and Val and / or PAA. (g) and (c) show the results of evaluating high temperature stress tolerance genes in tomatoes treated with high temperature stress and Val and / or PAA. (g) and (c) show the results of evaluating high temperature stress tolerance genes in tomatoes treated with high temperature stress and Val and / or PAA. (h ... Figure 9 shows the Brix of tomato fruits treated with high temperature stress and Val and / or PAA (pot experiment). Ave is the average, and R1, R2, and R3 are the values ​​for each individual plant. Figure 9 shows the total seed weight, fertile seed weight, and fruit fertility of rice plants treated with high temperature stress and Val and / or PAA. Figure 9a shows the results for total seed weight, Figure 9b shows the results for fertile seed weight, and Figure 9c shows the results for fruit fertility.

[0011] The present invention will be described in detail below.

[0012] In the present invention, the following components (A) and (B) are utilized: (A) a substance having the property of altering amino acid metabolism in plants; (B) a substance having auxin-like activity.

[0013] Components (A) and (B) are collectively referred to as the "active ingredients."

[0014] By utilizing an active ingredient, specifically by applying the active ingredient to a plant, it is possible to induce high temperature stress tolerance in the plant, i.e., the effect of inducing high temperature stress tolerance in the plant is obtained. This effect is also referred to as the "high temperature stress tolerance induction effect." "Induction of high temperature stress tolerance in a plant" may be used interchangeably with "conferring high temperature stress tolerance to a plant" or "improving high temperature stress tolerance in a plant." "High temperature stress tolerance" means tolerance to high temperature stress. High temperature stress tolerance is also referred to as "high temperature tolerance."

[0015] Examples of induction of high temperature stress tolerance include increased expression of genes involved in high temperature stress tolerance. In other words, induction of high temperature stress tolerance in plants can be confirmed, for example, using increased expression of genes involved in high temperature stress tolerance as an indicator. That is, if the expression of genes involved in high temperature stress tolerance increases when the active ingredient is used compared to when the active ingredient is not used, it can be determined that high temperature stress tolerance in plants has been induced by the active ingredient. Furthermore, the expression of genes involved in high temperature stress tolerance may increase when components (A) and (B) are used in combination compared to when components (A) or (B) are used alone. "Increased gene expression" may be used interchangeably with "induction of gene expression." "Increased gene expression" may specifically mean increased gene expression before, during, and / or after exposure to high temperature stress. "Before exposure to high temperature stress" may mean, for example, any time point before exposing a plant to high temperature stress. "Before exposure to high temperature stress" may specifically mean, for example, immediately before exposing a plant to high temperature stress. "During exposure to high temperature stress" may mean, for example, any time point during the period during which a plant is exposed to high temperature stress. "During exposure to high temperature stress" may specifically mean, for example, any time point during the period during which a plant is exposed to high temperature stress, when high temperature stress symptoms are induced in the plant without the use of an active ingredient. "After exposure to high temperature stress" may mean, for example, any time point after the plant is exposed to high temperature stress. "After exposure to high temperature stress" may specifically mean, for example, any time point after the plant is exposed to high temperature stress, when high temperature stress symptoms are induced in the plant without the use of an active ingredient. For example, the use of an active ingredient may increase the expression of a gene involved in high temperature stress tolerance by 1.2 times or more, preferably 1.5 times or more, and more preferably 2 times or more, compared to when the active ingredient is not used. Furthermore, "increased gene expression" also includes cases where the expression of a gene that is not observed when the active ingredient is not used is observed when the active ingredient is used. Examples of genes involved in high temperature stress tolerance include high temperature stress-responsive genes such as HSP100 and HSFA2.Use of an active ingredient may increase the expression of one or more (e.g., all) genes selected from these genes involved in high temperature stress tolerance. Increased gene expression can be confirmed, for example, by measuring the transcription level of the gene (e.g., the amount of mRNA), the translation level of the gene (e.g., the amount of protein encoded by the gene), or the activity of the protein encoded by the gene. Examples of methods for measuring mRNA levels include Northern hybridization and RT-PCR. Examples of methods for measuring protein levels include Western blotting. Methods for measuring protein activity can be appropriately selected depending on various conditions, such as the type of target protein.

[0016] Furthermore, examples of induction of high temperature stress tolerance in plants include alleviation of high temperature stress symptoms. That is, induction of high temperature stress tolerance in plants can be confirmed, for example, using the alleviation of high temperature stress symptoms as an indicator. That is, if high temperature stress symptoms are alleviated when the active ingredient is used compared to when the active ingredient is not used, it can be determined that high temperature stress tolerance in plants has been induced by the active ingredient. Furthermore, high temperature stress symptoms may be alleviated when the components (A) and (B) are used in combination compared to when the components (A) or (B) are used alone. "High temperature stress symptoms" may refer to symptoms caused by high temperature stress. Examples of high temperature stress symptoms include impaired plant growth, reduced plant yield, poor anther formation, reduced pollen fertility, plant death, plant cell death, reduced plant photosynthetic activity, reduced chlorophyll content in plant cells, and pollination inhibition. That is, induction of high temperature stress tolerance in plants (specifically, alleviation of high temperature stress symptoms) includes improvement of plant growth, increase in plant yield, suppression of poor anther formation, suppression of reduced pollen fertility, suppression of plant death, suppression of plant cell death, increase in plant photosynthetic activity, increase in chlorophyll content in plant cells, and suppression of pollination inhibition.

[0017] "Improvement of plant growth" may mean, for example, that the degree of growth of a plant after exposure to high temperature stress is greater when the active ingredient is used compared to when the active ingredient is not used. Examples of the degree of growth include growth amount and growth rate. "Growth amount" may mean, for example, the increase in fresh weight of the above-ground part of a plant. "Growth rate" may mean, for example, the increase in fresh weight of the above-ground part of a plant per unit time. By using the active ingredient, for example, the degree of growth of a plant after exposure to high temperature stress may be increased by 1.2 times or more, preferably 1.5 times or more, and more preferably 2 times or more compared to when the active ingredient is not used.

[0018] "Increased plant yield" may mean, for example, that the yield of a plant after exposure to high temperature stress is greater when the active ingredient is used compared to when the active ingredient is not used. Examples of increased plant yield include an increase in the overall yield of the plant, and an increase in the yield of parts of the plant, such as leaves, roots, fruits, and seeds. An increased plant yield may be measured, for example, as an increase in the fresh weight of the harvested plant or an increase in the number of harvested plants. Use of an active ingredient may increase the yield of a plant after exposure to high temperature stress by 1.2 times or more, preferably 1.5 times or more, and more preferably 2 times or more, compared to when the active ingredient is not used.

[0019] "Suppression of plant death" may mean, for example, that the rate of plant death due to exposure to high temperature stress when the active ingredient is used is lower than when the active ingredient is not used (i.e., the ratio of the number of surviving plants after exposure to high temperature stress to the number of surviving plants before exposure to high temperature stress subtracted from 100%). Use of the active ingredient may, for example, reduce the rate of plant death due to exposure to high temperature stress to 90% or less, preferably 70% or less, and more preferably 50% or less, compared to when the active ingredient is not used.

[0020] "Suppression of plant cell death" may mean, for example, that the cell death rate (i.e., the ratio of the number of dead cells to the total number of cells in the plant) after exposure to high temperature stress is lower when the active ingredient is used compared to when the active ingredient is not used. By using the active ingredient, for example, the cell death rate after exposure to high temperature stress may be reduced to 90% or less, preferably 70% or less, and more preferably 50% or less compared to when the active ingredient is not used.

[0021] "Increasing the photosynthetic activity of a plant" may mean, for example, that the photosynthetic activity of a plant after exposure to high temperature stress is greater when the active ingredient is used compared to when the active ingredient is not used. For example, the use of the active ingredient may increase the photosynthetic activity of a plant after exposure to high temperature stress by 1.2 times or more, preferably 1.5 times or more, and more preferably 2 times or more compared to when the active ingredient is not used.

[0022] "Increasing the chlorophyll content in plant cells" may mean, for example, that the chlorophyll content in plant cells after exposure to high temperature stress is greater when the active ingredient is used compared to when the active ingredient is not used. Use of the active ingredient may increase the chlorophyll content in plant cells after exposure to high temperature stress by 1.2 times or more, preferably 1.5 times or more, and more preferably 2 times or more compared to when the active ingredient is not used. The chlorophyll content in plant cells can be measured, for example, by the method described in JP 2012-197249 A.

[0023] Note that "reduction of high-temperature stress symptoms" also includes the complete disappearance of high-temperature stress symptoms. Furthermore, "reduction of high-temperature stress symptoms" includes both the reduction of high-temperature stress symptoms that may occur in the future (so-called preventive effect) and the reduction of high-temperature stress symptoms that have already occurred (so-called therapeutic effect). Reduction of high-temperature stress symptoms that may occur in the future includes cases where high-temperature stress symptoms do not occur in the future, and cases where high-temperature stress symptoms are reduced when high-temperature stress symptoms occur in the future. Reduction of high-temperature stress symptoms that have already occurred includes cases where high-temperature stress symptoms that have already occurred are improved, and cases where high-temperature stress symptoms that have already occurred are prevented from worsening. Reduction of high-temperature stress symptoms may be due, for example, to increased expression of genes involved in high-temperature stress resistance.

[0024] <1> Plants The type of plant is not particularly limited. The plant may be a woody plant or a herbaceous plant. Examples of plants include Gramineae plants (rice, barley, wheat, corn, sorghum, millet, sugarcane, oats, lawn grass, pearl millet, finger millet, fonio, etc.), Solanaceae plants (tomato, bell pepper, eggplant, potato, tobacco, etc.), Cucurbitaceae plants (cucumber, melon, pumpkin, etc.), Leguminous plants (pea, soybean, kidney bean, alfalfa, peanut, broad bean, cowpea, lentil, chickpea, clover, groundnut, bambara groundnut, etc.), Brassicaceae plants (radish, Chinese cabbage, cabbage, komatsuna, nanohana, bok choy, Arabidopsis, etc.), Rosaceae plants (strawberry, apple, pear, peach, etc.), and cruciferous plants. Examples of plants include plants from the family Crotalaceae (e.g., mulberry), family Malvaceae (e.g., cotton), family Apiaceae (e.g., carrot, parsley, celery), family Liliaceae (e.g., leek, onion, asparagus), family Asteraceae (e.g., burdock, sunflower, chrysanthemum, garland chrysanthemum, safflower, lettuce), family Amaranthaceae (e.g., sugar beet), family Ericaceae (e.g., blueberry, cranberry), family Vitaceae (e.g., grape), family Rutaceae (e.g., Satsuma mandarin, lemon, yuzu), family Rubiaceae (e.g., coffee tree), family Oleaceae (e.g., olive), family Lauraceae (e.g., avocado), family Anacardiaceae (e.g., mango, cashew tree), family Sapindaceae (e.g., lychee), and family Lamiaceae (e.g., coleus). Examples of plants include, in particular, plants from the family Solanaceae (e.g., tomato) and family Poaceae (e.g., rice). Examples of plants include, in particular, plants from which edible products such as fruit can be harvested. The plant may be one type of plant, or two or more types of plants.

[0025] <2> Active ingredient <2-1> Substance having the property of altering amino acid metabolism in plants: component (A) Component (A) is a substance having the property of altering amino acid metabolism in plants. As component (A), one type of component may be used, or two or more types of components may be used in combination.

[0026] In the present invention, any substance can be used as component (A) without limitation, as long as it has the activity of altering the amino acid metabolism of plants and exhibits the effects of the present invention. The phrase "a substance having the property of altering the amino acid metabolism of plants" does not limit the case where the substance itself has the property of altering the amino acid metabolism of plants, but also includes the case where another substance produced by metabolism of the substance has the property of altering the amino acid metabolism of plants.

[0027] Properties that alter amino acid metabolism include properties that inhibit amino acid biosynthesis.

[0028] Examples of the property of inhibiting amino acid biosynthesis include the property of inhibiting branched-chain amino acid biosynthesis and the property of inhibiting aromatic amino acid biosynthesis.

[0029] The property of inhibiting the biosynthesis of branched-chain amino acids includes the property of inhibiting the activity of enzymes in the biosynthetic pathway of branched-chain amino acids (also called "branched-chain amino acid synthases"). The property of inhibiting the biosynthesis of aromatic amino acids includes the property of inhibiting the activity of enzymes in the biosynthetic pathway of aromatic amino acids (also called "aromatic amino acid synthases").

[0030] Branched-chain amino acids include valine, leucine, and isoleucine. Aromatic amino acids include phenylalanine, tryptophan, and tyrosine. That is, "inhibiting the biosynthesis of branched-chain amino acids" may mean, for example, inhibiting the biosynthesis of one or more (i.e., one, two, or all three) amino acids selected from valine, leucine, and isoleucine. Furthermore, "inhibiting the biosynthesis of aromatic amino acids" may mean, for example, inhibiting the biosynthesis of one or more (i.e., one, two, or all three) amino acids selected from phenylalanine, tryptophan, and tyrosine.

[0031] (Component A1) Examples of substances that have the property of altering amino acid metabolism in plants include branched-chain amino acids, branched-chain amino acid derivatives (hereinafter collectively referred to as "branched-chain amino acids"), and intermediates in their biosynthetic pathways and consumption pathways (hereinafter collectively referred to as "component A1").

[0032] Branched-chain amino acid derivatives refer to various derivatives of branched-chain amino acids. Examples of branched-chain amino acid derivatives include non-standard amino acids, unnatural amino acids, amino alcohols, and amino acids in which one or more functional groups, such as terminal carbonyl groups and terminal amino groups, are substituted with various substituents. Specific examples of the substituents include alkyl groups, acyl groups, hydroxyl groups, amino groups, alkylamino groups, nitro groups, sulfonyl groups, and various protecting groups.

[0033] The amino acid derivative also includes glycosides, such as monosaccharides such as glucose, glucosamine, N-acetylglucosamine, mannose, galactose, fructose, ribose, lyxose, xylose, and arabinose; and polysaccharides composed of these monosaccharides.

[0034] Amino acid derivatives include intermediates in the biosynthetic and consumption pathways of branched-chain amino acids. In plants, branched-chain amino acids can generally be biosynthesized using pyruvate or ketobutyrate as a starting material. Ketobutyrate can be derived from threonine. Specifically, valine and leucine can be synthesized using pyruvate as a starting material via acetolactate. Specifically, isoleucine can be synthesized using pyruvate and ketobutyrate as starting materials via acetohydroxybutyrate. In other words, "intermediates in the biosynthetic pathway of branched-chain amino acids" may refer to compounds in the biosynthetic pathway from pyruvate or ketobutyrate to branched-chain amino acids (e.g., valine, leucine, and isoleucine). Furthermore, "intermediates in the consumption pathway of branched-chain amino acids" may refer to compounds produced by further metabolism of branched-chain amino acids (e.g., valine, leucine, and isoleucine). Specific examples of component A1 include pyruvic acid, ketobutyric acid, acetolactic acid, acetohydroxybutyric acid, 2,3-dihydroxyisovaleric acid, 2,3-dihydroxy-3-methylvaleric acid, α-ketoisovaleric acid, ketomethylvaleric acid, 2-isopropylmalic acid, 3-isopropylmalic acid, ketoisocaproic acid, valine, leucine, isoleucine, and derivatives thereof. Specific examples of component A1 include valine, leucine, and α-ketoisovaleric acid. Component A1 may be a single substance or a combination of two or more substances.

[0035] Each of the components A1 has the property of altering plant amino acid metabolism, for example, by inhibiting acetolactate synthase (ALS), a branched-chain amino acid synthase. ALS is also known as acetohydroxyacid synthase (AHAS). ALS catalyzes both the synthesis of acetolactate and acetohydroxyacid (EC 2.2.1.6).

[0036] Unless otherwise specified, branched-chain amino acids (e.g., valine, leucine, and isoleucine) may be in the D- or L-form, or a combination thereof. The ratio of D- to L-forms in a combination is not particularly limited. The ratio of D- or L-forms in a combination may be, for example, 20 to 80%, 30 to 70%, 40 to 60%, or 45 to 55% by molar ratio. The amino acid may particularly be in the L-form. When a branched-chain amino acid in the D- or L-form is selected, it is sufficient to use the branched-chain amino acid in the D- or L-form as an active ingredient, and this does not preclude the use of the branched-chain amino acid in the L- or D-form in combination.

[0037] (Component A2) Examples of substances that have the property of inhibiting the biosynthesis of branched-chain amino acids include substances that have inhibitory activity against acetolactate synthase (ALS), an enzyme that synthesizes branched-chain amino acids (hereinafter also referred to as "component A2" or "ALS inhibitor").

[0038] ALS inhibitors are preferably non-toxic or low-toxic to humans. Traditionally, ALS inhibitors with long-lasting activity and plant selectivity have been used as herbicides. ALS inhibitors inhibit plant ALS activity, thereby inhibiting the biosynthesis of valine, leucine, and isoleucine, altering plant amino acid metabolism and affecting plant growth.

[0039] ALS inhibitors include sulfonylurea compounds (SU agents), imidazoline compounds, pyrimidinylsalicylic acid compounds, triazolopyrimidine sulfonamide compounds, pyrimidinyl(thio)benzoate (PTB) compounds, sulfonanilide (SA) compounds, and sulfonylaminocarbonyltriazolinone (SCT) compounds.

[0040] Examples of sulfonylurea compounds include thifensulfuron methyl, trifloxysulfuron sodium salt, pyrazosulfuron ethyl, bensulfuron methyl, cinosulfuron, imazosulfuron, azimsulfuron, halosulfuron methyl, ethoxysulfuron, cyclosulfamuron, amidosulfuron, chlorimuron ethyl, sulfometuron methyl, oxasulfuron, primisulfuron, mesosulfuron methyl, foramsulfuron, chlorsulfuron, metsulfuron methyl, tribenuron methyl, iodosulfuron, isosulfuron methyl sodium salt, prosulfuron, triasulfuron, tritosulfuron, ethametsulfuron methyl, triflusulfuron methyl, rimsulfuron, nicosulfuron, flupyrsulfuron, and sulfosulfuron.

[0041] Examples of the imidazolinone compounds include imazapyr, imazamethabenz, imazamethapyr, imazethapyr, imazamox, imazaquin, and imazaquin ammonium.

[0042] Examples of pyrimidinylsalicylic acid compounds include bispyribac-sodium, pyrithiobac-sodium, pyriminobac-methyl, pyriftalid, and pyribenzoxim.

[0043] Examples of triazolopyrimidine sulfonamide compounds include flumetsulam, florasulam, metosulam, diclosulam, cloransulam-methyl, penosculum, and DASH-001 (penoxsulam).

[0044] Examples of pyrimidinyl (thio)benzoate (PTB) compounds include pyriminobac-methyl, bispyribac-sodium salt, and pyrithiobac-sodium salt.

[0045] Examples of sulfonanilide (SA) compounds include pyrimisulfan and triafamone.

[0046] Examples of sulfonylaminocarbonyltriazolinone (SCT) compounds include flucarbazone sodium salt and thiencarbazone methyl.

[0047] ALS inhibitors include thifensulfuron methyl, imazapyr, bispyribac sodium, among others.

[0048] As component A2, one kind of substance may be used, or two or more kinds of substances may be used in combination.

[0049] (Component A3) Examples of compounds that have the property of inhibiting the biosynthesis of aromatic amino acids include substances that have inhibitory activity against 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), an aromatic amino acid synthase (hereinafter also referred to as "Component A3" or "EPSPS inhibitor").

[0050] EPSPS inhibitors are preferably non-toxic or have low toxicity to humans. Conventionally, EPSPS inhibitors have been used as herbicides. EPSPS inhibitors inhibit EPSPS activity in plants, thereby inhibiting the biosynthesis of phenylalanine, tryptophan, and tyrosine via the shikimate pathway and altering amino acid metabolism in plants, thereby affecting plant growth.

[0051] Examples of EPSPS inhibitors include glyphosate. Glyphosate is known as an agricultural chemical ingredient that inhibits the shikimate pathway. As described below, glyphosate may be in the free form, a salt, or a combination thereof. The glyphosate is preferably a water-soluble glyphosate salt. Examples of water-soluble glyphosate salts include potassium salt, isopropylamine salt, ammonium salt, sodium salt, and trimethylsulfonium salt of glyphosate.

[0052] As component A3, one kind of substance may be used, or two or more kinds of substances may be used in combination.

[0053] When component (A) can form a salt, component (A) may be used in its free form, its salt, or a combination thereof. That is, unless otherwise specified, the term "component (A)" may refer to component (A) in its free form, its salt, or a combination thereof. The salt is not particularly limited as long as it does not impair the effects of the present invention. For example, salts of acidic groups such as carboxyl groups include ammonium salts, salts with alkali metals such as sodium and potassium, salts with alkaline earth metals such as calcium and magnesium, aluminum salts, zinc salts, salts with organic amines such as triethylamine, ethanolamine, morpholine, pyrrolidine, piperidine, piperazine, and dicyclohexylamine, and salts with basic amino acids such as arginine and lysine. Furthermore, examples of salts of basic groups such as amino groups include salts with inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid, nitric acid, and hydrobromic acid, salts with organic carboxylic acids such as acetic acid, citric acid, benzoic acid, maleic acid, fumaric acid, tartaric acid, succinic acid, tannic acid, butyric acid, hybenzic acid, pamoic acid, enanthic acid, decanoic acid, teoclic acid, salicylic acid, lactic acid, oxalic acid, mandelic acid, and malic acid, and salts with organic sulfonic acids such as methanesulfonic acid, benzenesulfonic acid, and p-toluenesulfonic acid. As the salt, one type of salt may be used, or two or more types of salts may be used in combination.

[0054] Furthermore, when component (A) can form a hydrate, component (A) may be used as a non-hydrate, a hydrate, or a combination thereof. That is, the term "component (A)" (e.g., "component (A) in free form" or "salt of component (A)") may encompass both the non-hydrate and the hydrate, unless otherwise specified.

[0055] Component (A) may be in any form, such as an ion, when used.

[0056] As component (A), one kind of substance may be used, or two or more kinds of substances may be used in combination. When two or more kinds of components are selected as component (A), the "amount" or "concentration" of component (A) (i.e., the "amount" or "concentration" of component (A)) may mean the total amount or total concentration of the selected components, unless otherwise specified.

[0057] Component (A) may be a commercially available product or may be obtained by appropriate production. The production method of component (A) is not particularly limited. Component (A) can be produced, for example, by a known method. Specific examples of component (A) include chemical synthesis, enzymatic reaction, fermentation, extraction, or a combination thereof. Component (A) may be purified to a desired degree or not. That is, component (A) may be a purified product, or a material containing component (A). Specific examples of materials containing component (A) include fermentation products such as culture solutions, bacterial cells, and culture supernatants obtained by culturing microorganisms capable of producing component (A), agricultural and aquatic livestock products containing component (A), and processed products thereof. Processed products include materials such as the above-mentioned fermentation products that have been subjected to processes such as concentration, dilution, drying, fractionation, extraction, and purification. For example, branched-chain amino acids (e.g., valine, leucine, and isoleucine) may be commercially available as reagents, purified or crude products produced by fermentation, by-products resulting from the purification process, or mixtures containing branched-chain amino acids, such as marine extracts or protein hydrolysates. Furthermore, pesticide ingredients (e.g., ALS inhibitors or EPSPS inhibitors) may be commercially available as reagents or mixtures of pesticides containing the pesticide ingredients. Component (A) may contain, for example, a material containing component (A) at a content of 1% (w / w) or more, 5% (w / w) or more, 10% (w / w) or more, 30% (w / w) or more, 50% (w / w) or more, 70% (w / w) or more, 90% (w / w) or more, or 95% (w / w) or more.

[0058] <2-2> Substance having auxin-like activity: component (B) Component (B) is a substance having auxin-like activity. As component (B), one substance having auxin-like activity may be used, or two or more substances having auxin-like activity may be used in combination.

[0059] "Auxin" is a general term for plant hormones that have the function of promoting plant growth (specifically, elongation growth). Auxin may be either natural or synthetic. In the present invention, any substance can be used as component (B) without limitation, as long as it has auxin-like plant growth-promoting activity and exhibits the effects of the present invention. "A substance having auxin-like activity" does not mean that the substance itself has plant growth-promoting activity, but also includes cases where another substance produced by metabolism of the substance has plant growth-promoting activity. Examples of such substances include, but are not limited to, auxin, auxin analogs, auxin receptor agonists, and signaling factors downstream of auxin. Preferably, auxin can be used.

[0060] Auxins include indole-3-acetic acid (IAA), 4-chloroindole-3-acetic acid (4Cl-IAA), 2,4-dichlorophenoxyacetic acid (2,4-D), 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), naphthaleneacetic acid, naphthoxyacetic acid, and phenylacetic acid (PAA). Auxins, particularly IAA and PAA, are preferred. Examples of auxin analogs include the auxin receptor agonist RubNeddin.

[0061] Component (B) may be a commercially available product or may be obtained by appropriate production. The production method of component (B) is not particularly limited. Component (B) can be produced, for example, by a known method. Specific examples of component (B) include chemical synthesis, enzymatic reaction, fermentation, extraction, or a combination thereof. Component (B) may be purified to a desired degree or not. That is, component (B) may be a purified product, or a material containing component (B). Specific examples of materials containing component (B) include fermentation products such as culture broth, bacterial cells, and culture supernatant obtained by culturing a microorganism capable of producing component (B), agricultural, aquatic, and livestock products containing component (B), and processed products thereof. Processed products include materials such as the above-mentioned fermentation products that have been subjected to processes such as concentration, dilution, drying, fractionation, extraction, and purification. As component (B), for example, a material having a component (B) content of 1% (w / w) or more, 5% (w / w) or more, 10% (w / w) or more, 30% (w / w) or more, 50% (w / w) or more, 70% (w / w) or more, 90% (w / w) or more, or 95% (w / w) or more may be used.

[0062] <3> Composition of the Present Invention The composition of the present invention is a composition containing active ingredients (i.e., the above-mentioned components (A) and (B)).

[0063] The composition of the present invention can be used by applying it to plants. The use of the composition of the present invention is described in detail in the "Method of the Present Invention." By utilizing the composition of the present invention, specifically by applying the composition of the present invention to plants, high temperature stress tolerance in plants can be induced. That is, the composition of the present invention may be a composition for inducing high temperature stress tolerance in plants. Specifically, the composition of the present invention (e.g., a composition for inducing high temperature stress tolerance in plants) may be a composition for improving plant growth, increasing plant yield, suppressing plant death, suppressing plant cell death, increasing plant photosynthetic activity, and / or increasing chlorophyll content in plant cells. Induction of high temperature stress tolerance in plants may be, for example, by increasing the expression of a gene involved in high temperature stress tolerance. That is, the composition of the present invention (e.g., a composition for inducing high temperature stress tolerance in plants) may be, for example, a composition for increasing the expression of a gene involved in high temperature stress tolerance in plants. A composition for inducing high temperature stress tolerance in plants is also referred to as a "high temperature stress tolerance inducer for plants."

[0064] The composition of the composition of the present invention is not particularly limited as long as the composition of the present invention contains an active ingredient and can achieve the desired effect, such as the effect of inducing high temperature stress tolerance. The types and amounts of ingredients contained in the composition of the present invention can be appropriately selected depending on various conditions, such as the type of plant, the plant cultivation method, the growth stage of the plant, the nature of the high temperature stress conditions, the degree of high temperature stress symptoms, and the manner of use of the composition of the present invention.

[0065] The composition of the present invention may consist of an active ingredient or may contain ingredients other than the active ingredient. Examples of ingredients other than the active ingredient include those commonly used in agricultural chemicals, fertilizers, pharmaceuticals, and other applications. Specific examples of such ingredients include additives such as excipients, binders, disintegrants, lubricants, stabilizers, diluents, surfactants, spreading agents, pH adjusters, fertilizer ingredients, agricultural chemical ingredients, water, alcohol, vitamins, and minerals. Spreading agents may be used, for example, to enhance the spreading ability of active ingredients on plants. Surfactants may be used, for example, to enhance the penetration of active ingredients into plants. Examples of excipients include solid carriers and liquid carriers. Solid carriers include inorganic substances such as vermiculite, talc, diatomaceous earth, kaolin, calcium carbonate, clay, calcium hydroxide, white clay, and silica gel, as well as wheat flour and starch. Liquid carriers include alcohols such as ethanol and ethylene glycol, ketones such as acetone, ethers such as dioxane and tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, and acetonitrile. A solid carrier may be used, for example, when the composition of the present invention is a solid formulation. A liquid carrier may be used, for example, when the composition of the present invention is a liquid formulation. As a spreading agent, Approach BI TM (Kao Corporation), Mix Power TM (Syngenta Japan Ltd.), Squash TM (Maruwa Biochemical Co., Ltd.). As the component other than the active ingredient, one component may be used, or two or more components may be used. The composition of the present invention may be formulated as appropriate. The dosage form of the composition of the present invention is not particularly limited. The dosage form of the composition of the present invention can be selected as appropriate depending on various conditions such as the mode of use of the composition of the present invention. Dosage forms include liquids, powders, granules, tablets, emulsions, wettable powders, oil solutions, aerosols, and flowables.

[0066] The total content of the active ingredients in the composition of the present invention is more than 0% (w / w) and 100% (w / w) or less. The total content of the active ingredients in the composition of the present invention is, for example, 0.000005% or more, 0.00001% or more, 0.00002% or more, 0.00005% or more, 0.0001% or more, 0.0002% or more, 0.0005% or more, 0.001% (w / w) or more, 0.002% (w / w) or more, 0.005% (w / w) or more, 0.01% (w / w) or more, 0.02% (w / w) or more, 0.05% (w / w) or more, 0.1% (w / w) or more, 0.2% (w / w) or more, 0.5% (w / w) or more, 1% (w / w) or more, 2% (w / w) or more, 5% (w / w). / w) or more, or 10% (w / w) or more, or 100% (w / w) or less, 99.9% (w / w) or less, 70% (w / w) or less, 50% (w / w) or less, 30% (w / w) or less, 20% (w / w) or less, 15% (w / w) or less, 10% (w / w) or less, 5% (w / w) or less, 2% (w / w) or less, 1% (w / w) or less, 0.5% (w / w) or less, 0.2% (w / w) or less, 0.1% (w / w) or less, 0.05% (w / w) or less, or 0.02% (w / w) or less, or any compatible combination thereof.

[0067] In the composition of the present invention, the ratio of the content of component (B) to the content of component (A) (content of component (B) / content of component (A)) may be, for example, in molar ratio, 0.0002 or more, 0.0005 or more, 0.001 or more, 0.002 or more, 0.005 or more, 0.01 or more, 0.02 or more, 0.05 or more, 0.1 or more, 0.2 or more, 0.5 or more, 1 or more, 2 or more, 5 or more, 10 or more, 20 or more, 50 or more, 100 or more, or It may be equal to or greater than 1000, 500 or less, 200 or less, 100 or less, 50 or less, 20 or less, 10 or less, 5 or less, 2 or less, 10 or less, 5 or less, 2 or less, 1 or less, 0.5 or less, 0.2 or less, 0.1 or less, 0.05 or less, 0.02 or less, 0.01 or less, 0.005 or less, 0.002 or less, 0.001 or less, or 0.0005 or less, or any compatible combination thereof. The ratio of the content of component (B) to the content of component (A) (content of component (B) / content of component (A)) may be, specifically, for example, in molar ratio, 0.0002 to 0.0005, 0.0005 to 0.001, 0.001 to 0.002, 0.002 to 0.005, 0.005 to 0.01, 0.01 to 0.02, 0.02 to 0.05, 0.05 to 0.1, 0.1 to 0.2, 0.2 to 0.5, 0.5 to 1, 1 to 2, 2 to 5, 5 to 10, 10 to 20, 20 to 50, 50 to 100, 100 to 200, 200 to 500, or 500 to 1000. When the composition of the present invention contains two or more types of component (A), the contents of those two or more types of component (A) may be set, independently or in total, so as to satisfy the ratio of the content of component (B) to the content of component (A) exemplified above. However, when the composition of the present invention contains two or more types of component (A), the "content of component (A) in the composition of the present invention" means the total content of those two or more types of component (A) in the composition of the present invention, unless otherwise specified. When the composition of the present invention contains two or more types of component (B), the contents of those two or more types of component (B) may be set, independently or in total, so as to satisfy the ratio of the content of component (B) to the content of component (A) exemplified above.However, when the composition of the present invention contains two or more types of component (B), the "content of component (B) in the composition of the present invention" means the total content of those two or more types of component (B) in the composition of the present invention, unless otherwise specified.

[0068] When at least component A1 is used as component (A), in the composition of the present invention, the ratio of the content of component (B) to the content of component A1 (content of component (B) / content of component A1) may be, for example, in molar ratio, 0.0002 or more, 0.0005 or more, 0.001 or more, 0.002 or more, 0.005 or more, or 0.01 or more, or 0.02 or less, 0.01 or less, 0.005 or less, 0.002 or less, 0.001 or less, or 0.0005 or less, or any compatible combination thereof. The ratio of the content of component (B) to the content of component A1 (content of component (B) / content of component A1) may be, for example, in molar ratio, 0.0002 to 0.0005, 0.0005 to 0.001, 0.001 to 0.002, 0.002 to 0.005, 0.005 to 0.01, or 0.01 to 0.02. The ratio of the content of component (B) to the content of component A1 (content of component (B) / content of component A1) may be, for example, in molar ratio, 0.0002 to 0.02, 0.0005 to 0.01, or 0.001 to 0.005. When the composition of the present invention contains two or more types of component A1, the contents of those two or more types of component A1 may be set independently or in total so as to satisfy the ratio of the content of component (B) to the content of component A1 exemplified above. However, when the composition of the present invention contains two or more types of component A1, the "content of component A1 in the composition of the present invention" means the total content of those two or more types of component A1 in the composition of the present invention, unless otherwise specified.

[0069] When at least component A2 is used as component (A), the ratio of the content of component (B) to the content of component A2 in the composition of the present invention (content of component (B) / content of component A2) may be, for example, in molar ratio, 2 or more, 5 or more, 10 or more, 20 or more, 50 or more, 100 or more, 200 or more, or 500 or more, or may be 1,000 or less, 500 or less, 200 or less, 100 or less, 50 or less, 20 or less, 10 or less, or 5 or less, or any combination thereof that is not contradictory. Specifically, the ratio of the content of component (B) to the content of component A2 (content of component (B) / content of component A2) may be, for example, in molar ratio, 2 to 5, 5 to 10, 10 to 20, 20 to 50, 50 to 100, 100 to 200, 200 to 500, or 500 to 1,000. The ratio of the content of component (B) to the content of component A2 (content of component (B) / content of component A2) may be, for example, a molar ratio of 2 to 1,000, 5 to 500, or 10 to 200. When the composition of the present invention contains two or more types of component A2, the contents of those two or more types of component A2, either independently or in total, may be set so as to satisfy the above-exemplified ratio of the content of component (B) to the content of component A2. However, when the composition of the present invention contains two or more types of component A2, the term "content of component A2 in the composition of the present invention" refers to the total content of those two or more types of component A2 in the composition of the present invention, unless otherwise specified.

[0070] When at least component A3 is used as component (A), the ratio of the content of component (B) to the content of component A3 in the composition of the present invention (content of component (B) / content of component A3) may be, for example, in molar ratio, 0.1 or more, 0.2 or more, 0.5 or more, 1 or more, 2 or more, or 5 or more, or may be 10 or less, 5 or less, 2 or less, 1 or less, 0.5 or less, or 0.2 or less, or any combination thereof that is not contradictory. Specifically, the ratio of the content of component (B) to the content of component A3 (content of component (B) / content of component A3) may be, for example, in molar ratio, 0.1 to 0.2, 0.2 to 0.5, 0.5 to 1, 1 to 2, 2 to 5, or 5 to 10. The ratio of the content of component (B) to the content of component A3 (content of component (B) / content of component A3) may be, for example, a molar ratio of 0.1 to 10, 0.2 to 5, or 0.5 to 2. When the composition of the present invention contains two or more types of component A3, the contents of those two or more types of component A3, either independently or in total, may be set so as to satisfy the above-exemplified ratio of the content of component (B) to the content of component A3. However, when the composition of the present invention contains two or more types of component A3, the term "content of component A3 in the composition of the present invention" refers to the total content of those two or more types of component A3 in the composition of the present invention, unless otherwise specified.

[0071] The content of each active ingredient in the composition of the present invention can be set, for example, so as to satisfy the total content and content ratio of the active ingredients exemplified above.

[0072] In addition, the content of each active ingredient in the composition of the present invention can be set, for example, so that the concentration of each active ingredient is within a predetermined range when the composition of the present invention is used. The concentration of the active ingredient when the composition of the present invention is used is also referred to as the "use concentration of the active ingredient" or the "application concentration of the active ingredient". The use concentration of the active ingredient may be, in particular, the concentration when the composition of the present invention is used in the form of a liquid.

[0073] The concentration of the active ingredient used is not particularly limited as long as the desired effect, such as the effect of inducing high temperature stress tolerance, is obtained. The concentration of the active ingredient used can be appropriately set depending on various conditions, such as the type of active ingredient, the type of plant, the plant cultivation method, the growth stage of the plant, the nature of the high temperature stress conditions, and the degree of high temperature stress symptoms. The concentration of the active ingredient used may be set, for example, to a concentration that allows the plant to survive to the desired extent.

[0074] The concentration of component (A) used is, for example, 5 nM or more, 10 nM or more, 20 nM or more, 50 nM or more, 100 nM or more, 200 nM or more, 500 nM or more, 1 μM or more, 2 μM or more, 5 μM or more, 10 μM or more, 20 μM or more, 50 μM or more, 100 μM or more, 200 μM or more, 500 μM or more, 1 mM or more. 200 mM or less, 100 mM or less, 50 mM or less, 20 mM or less, 10 mM or less, 5 mM or less, 2 mM or less, 1 mM or less, 500 μM or less, 200 μM or less, 100 μM or less, 50 μM or less, 20 μM or less, 10 μM or less, 5 μM or less, 2 Less than μM, less than 1 μM, 500 The concentration may be 0.1 nM or less, 200 nM or less, 100 nM or less, 50 nM or less, 20 nM or less, or 10 nM or less, or any compatible combination thereof. Specific examples of the concentration of component (A) used include 5 nM to 10 nM, 10 nM to 20 nM, 20 nM to 50 nM, 50 nM to 100 nM, 100 nM to 200 nM, 200 nM to 500 nM, 500 nM to 1 μM, 1 μM to 2 μM, 2 μM to 5 μM, 5 μM to 10 μM, 10 μM to 20 μM, 20 μM to 50 μM, 50 μM to 100 μM, 100 μM to 200 μM, 200 μM to 500 μM, 500 μM to 1 mM, 1 mM to 2 mM, 2 mM to 5 mM, 5 mM to 10 mM, 10 mM to 20 mM, 20 mM to 50 mM, 50 mM to 100 mM, or 100 mM to 200 mM. When two or more kinds of component (A) are used, the use concentrations of those two or more kinds of component (A) may be set independently or in total within the range of the use concentration of component (A) exemplified above. However, when two or more kinds of component (A) are used, the "use concentration of component (A)" means the total use concentration of those two or more kinds of component (A) unless otherwise specified.

[0075] When at least component A1 is used as component (A), the concentration of component A1 may be, for example, 200 μM or more, 500 μM or more, 1 mM or more, 2 mM or more, 5 mM or more, 10 mM or more, 20 mM or more, 50 mM or more, or 100 mM or more, or 200 mM or less, 100 mM or less, 50 mM or less, 20 mM or less, 10 mM or less, 5 mM or less, 2 mM or less, 1 mM or less, or 500 μM or less, or a compatible combination thereof. Specifically, the concentration of component A1 may be, for example, 200 μM to 500 μM, 500 μM to 1 mM, 1 mM to 2 mM, 2 mM to 5 mM, 5 mM to 10 mM, 10 mM to 20 mM, 20 mM to 50 mM, 50 mM to 100 mM, or 100 mM to 200 mM. The use concentration of component A1 may be, for example, 200 μM to 200 mM, 500 μM to 100 mM, or 1 mM to 50 mM. When two or more types of component A1 are used, the use concentrations of those two or more types of component A1 may be set independently or in total within the range of the use concentration of component A1 exemplified above. However, when two or more types of component A1 are used, the "use concentration of component A1" refers to the total use concentration of those two or more types of component A1, unless otherwise specified.

[0076] When at least component A2 is used as component (A), the concentration of component A2 used may be, for example, 5 nM or more, 10 nM or more, 20 nM or more, 50 nM or more, 100 nM or more, 200 nM or more, 500 nM or more, 1 μM or more, 2 μM or more, 5 μM or more, or 10 μM or more, or 20 μM or less, 10 μM or less, 5 μM or less, 2 μM or less, 1 μM or less, 500 nM or less, 200 nM or less, 100 nM or less, 50 nM or less, 20 nM or less, or 10 nM or less, or any compatible combination thereof. The use concentration of component A2 may be, for example, 5 nM to 10 nM, 10 nM to 20 nM, 20 nM to 50 nM, 50 nM to 100 nM, 100 nM to 200 nM, 200 nM to 500 nM, 500 nM to 1 μM, 1 μM to 2 μM, 2 μM to 5 μM, 5 μM to 10 μM, or 10 μM to 20 μM. The use concentration of component A2 may be, for example, 5 nM to 5 μM, 10 nM to 2 μM, or 20 nM to 1 μM. When two or more types of component A2 are used, the use concentrations of those two or more types of component A2 may be set independently or in total within the use concentration range of component A2 exemplified above. However, when two or more kinds of component A2 are used, the "concentration of component A2 used" means the total concentration of the two or more kinds of component A2 used, unless otherwise specified.

[0077] When at least component A3 is used as component (A), the concentration of component A3 used may be, for example, 500 nM or more, 1 μM or more, 2 μM or more, 5 μM or more, 10 μM or more, 20 μM or more, 50 μM or more, 100 μM or more, or 200 μM or more, or 500 μM or less, 200 μM or less, 100 μM or less, 50 μM or less, 20 μM or less, 10 μM or less, 5 μM or less, 2 μM or less, or 1 μM or less, or a compatible combination thereof. Specifically, the concentration of component A3 used may be, for example, 500 nM to 1 μM, 1 μM to 2 μM, 2 μM to 5 μM, 5 μM to 10 μM, 10 μM to 20 μM, 20 μM to 50 μM, 50 μM to 100 μM, 100 μM to 200 μM, or 200 μM to 500 μM. The use concentration of component A3 may be, for example, 500 nM to 100 μM, 1 μM to 50 μM, or 2 μM to 20 μM. When two or more types of component A3 are used, the use concentrations of those two or more types of component A3 may be set independently or in total within the range of the use concentration of component A3 exemplified above. However, when two or more types of component A3 are used, the "use concentration of component A3" refers to the total use concentration of those two or more types of component A3, unless otherwise specified.

[0078] The concentration of component (B) used may be, for example, 500 nM or more, 1 μM or more, 2 μM or more, 5 μM or more, 10 μM or more, 20 μM or more, 50 μM or more, 100 μM or more, or 200 μM or more, or 500 μM or less, 200 μM or less, 100 μM or less, 50 μM or less, 20 μM or less, 10 μM or less, 5 μM or less, 2 μM or less, or 1 μM or less, or a compatible combination thereof. Specifically, the concentration of component (B) used may be, for example, 500 nM to 1 μM, 1 μM to 2 μM, 2 μM to 5 μM, 5 μM to 10 μM, 10 μM to 20 μM, 20 μM to 50 μM, 50 μM to 100 μM, 100 μM to 200 μM, or 200 μM to 500 μM. The use concentration of component (B) may be, for example, 500 nM to 500 μM, 1 μM to 200 μM, or 2 μM to 100 μM. When two or more components (B) are used, the use concentrations of those two or more components (B) may be set independently or in total within the range of the use concentration of component (B) exemplified above. However, when two or more components (B) are used, the "use concentration of component (B)" refers to the total use concentration of those two or more components (B) unless otherwise specified.

[0079] When a material containing an active ingredient is used, the amount of the active ingredient (e.g., content (concentration) or amount used) is calculated based on the amount of the active ingredient itself in the material. When the active ingredient forms a salt or hydrate, the amount of the active ingredient (e.g., content (concentration) or amount used) is calculated based on the mass of the salt or hydrate converted to the mass of an equimolar free form.

[0080] The active ingredient and other ingredients may be mixed together and contained in the composition of the present invention, or may be contained separately or in any combination. For example, the composition of the present invention may be provided as a set of component (A) and component (B), each packaged separately. In such a case, component (A) and component (B) may be applied to plants in combination as appropriate.

[0081] <4> Method of the Present Invention The method of the present invention is a method comprising applying the active ingredients (i.e., the above-mentioned components (A) and (B)) to a plant. The method of the present invention can be carried out, for example, to obtain the effects exemplified above.

[0082] By practicing the method of the present invention, specifically by applying an active ingredient to a plant, high temperature stress tolerance can be induced in the plant. That is, the method of the present invention may be a method for inducing high temperature stress tolerance in a plant. Induction of high temperature stress tolerance in a plant may be, for example, by increasing the expression of a gene involved in high temperature stress tolerance. The method of the present invention (e.g., a method for inducing high temperature stress tolerance in a plant) may specifically be, for example, a method for improving plant growth, increasing plant yield, suppressing plant death, suppressing plant cell death, increasing plant photosynthetic activity, and / or increasing chlorophyll content in plant cells. That is, the method of the present invention (e.g., a method for inducing high temperature stress tolerance in a plant) may be, for example, a method for increasing the expression of a gene involved in high temperature stress tolerance in a plant.

[0083] The active ingredient can be applied to a plant, for example, using the composition of the present invention (i.e., by applying the composition of the present invention). That is, one embodiment of the method of the present invention may be, for example, a method comprising applying the composition of the present invention to a plant. "Applying an active ingredient to a plant" also includes applying the composition of the present invention to a plant. The composition of the present invention can be applied to a plant, for example, as is, or after being diluted, dispersed, or dissolved in a liquid such as water, physiological saline, a buffer solution, alcohol, or DMSO. That is, the composition of the present invention can be applied to a plant, for example, after adjusting the concentration to obtain the active ingredient use concentration as exemplified above. The composition of the present invention can be applied to a plant, particularly in liquid form. The active ingredients may be applied to a plant in a premixed state, or each may be applied to a plant separately. That is, for example, when the active ingredients are mixed together and contained in the composition of the present invention, the active ingredients can be applied to a plant in a premixed state by applying the composition of the present invention to a plant. Also, for example, when the active ingredients are contained separately in the composition of the present invention, the active ingredients may be mixed together and then applied to the plant, or may be applied separately to the plant. When the active ingredients are applied separately to the plant, the active ingredients may or may not be applied simultaneously to the plant. When the active ingredients are not applied simultaneously to the plant, the order of application of component (A) and component (B) is not particularly limited. For example, component (A) may be applied first, or component (B) may be applied first. For example, component (A) may be applied first in particular. When the active ingredients are not applied simultaneously to the plant, the interval between application of component (A) and application of component (B) is not particularly limited, as long as the desired effect, such as the effect of inducing high temperature stress tolerance, is obtained. The interval between the application of component (A) and the application of component (B) may be, for example, within 50 days, within 30 days, within 20 days, within 15 days, within 10 days, within 7 days, within 5 days, within 3 days, or within 1 day. The composition of the present invention may also be used in combination with other components. The same description of the components other than the active ingredient in the description of the composition of the present invention can be applied mutatis mutandis to the other components. That is, the composition of the present invention may also be used in combination with additives such as a spreading agent.

[0084] The method of application of the composition of the present invention is not particularly limited as long as the desired effect, such as the effect of inducing high temperature stress tolerance, is obtained. The method of application of the composition of the present invention can be appropriately selected depending on various conditions, such as the type of active ingredient, the type of plant, the plant cultivation method, the plant growth stage, the nature of the high temperature stress conditions, and the severity of the high temperature stress symptoms. The composition of the present invention can be applied to plants, for example, by a conventional method for applying pesticides or fertilizers to plants. The composition of the present invention can be applied to plants, for example, by a conventional method for applying pesticides or fertilizers to plants. The composition of the present invention may be applied to the plant itself, to the medium in which the plant is cultivated, or a combination thereof. "Applying an active ingredient to a plant" is not limited to applying the composition of the present invention to the plant itself, but also includes applying the composition of the present invention to the medium in which the plant is cultivated. The medium in which the plant is cultivated is also referred to as a "growth medium" or "growth system." The growth medium can be appropriately selected depending on various conditions, such as the type of plant and the cultivation method. The plant cultivation method is not particularly limited. Plant cultivation can be carried out, for example, by the same method as a conventional plant cultivation method, except for applying the composition of the present invention. Plant cultivation methods include soil cultivation, nutrient solution cultivation, and nutrient solution soil cultivation. Nutrient solution cultivation includes hydroponics and solid medium cultivation. Hydroponics includes nutrient film technique (NFT) and deep flow technique (DFT). That is, the medium (growth medium) in which plants are cultivated includes soil, hydroponic culture solution, and solid medium. Application to the plant itself includes spraying or coating the plant, and immersion of the plant. The composition of the present invention may be applied to the entire plant or to a part of the plant. For example, when the plant is a plant, the composition of the present invention may be applied to the entire plant body or to a part of the plant body. The composition of the present invention may be applied to, for example, the entire above-ground part of the plant body. Examples of parts of the plant body include leaves, stems, trunks, roots, fruits, and seeds. Examples of parts of the plant body include leaves, in particular.When the composition of the present invention is applied to leaves, the composition of the present invention may be applied to only one or both of the upper and lower surfaces of the leaves. Specific examples of application to plants include foliar spraying and root dipping. Application to growth media include spraying, irrigation, and mixing into the growth media. Specific examples of application (e.g., spraying) of the composition of the present invention to the growth media may be through an irrigation tube. Application to the growth media may be carried out so that the active ingredient reaches a position where it can act on the plant. For example, application to the medium in which the plant is grown may be carried out so that the active ingredient reaches the rhizosphere of the plant.

[0085] The application timing of the composition of the present invention is not particularly limited as long as the desired effect, such as the effect of inducing high temperature stress tolerance, can be obtained. The application timing of the composition of the present invention can be appropriately selected depending on various conditions, such as the type of active ingredient, the type of plant, the plant cultivation method, the growth stage of the plant, the nature of the high temperature stress conditions, and the severity of high temperature stress symptoms. The composition of the present invention can be applied to a plant, for example, before the onset of high temperature stress symptoms. By applying the composition of the present invention to a plant before the onset of high temperature stress symptoms, it is possible to, for example, alleviate high temperature stress symptoms that may occur in the future. The composition of the present invention can also be applied to a plant after the onset of high temperature stress symptoms. By applying the composition of the present invention to a plant after the onset of high temperature stress symptoms, it is possible to alleviate high temperature stress symptoms that have already occurred. The composition of the present invention can be applied, for example, before the completion of the vegetative growth stage of the plant. The composition of the present invention can also be applied, for example, before the completion of the reproductive stage of the plant (specifically, pollen formation). The composition of the present invention can also be applied, for example, after the onset of flowering of the plant. When the active ingredients are applied to plants separately, for example, component (A) may be applied before the completion of the vegetative growth stage of the plant, and component (B) may be applied before the completion of the reproductive stage of the plant (specifically, pollen formation). The composition of the present invention may be applied only once, or may be applied twice or more times. The composition of the present invention may be applied intermittently or continuously.

[0086] The application amount of the composition of the present invention is not particularly limited as long as the desired effect, such as the effect of inducing high temperature stress tolerance, is obtained. The application amount of the composition of the present invention can be appropriately selected depending on various conditions, such as the type of active ingredient, the type of plant, the method of cultivating the plant, the growth stage of the plant, the nature of the high temperature stress conditions, the degree of the high temperature stress symptoms, and the method and timing of application of the composition of the present invention.

[0087] The application rate of the composition of the present invention may be, for example, 100 L / ha or more, 200 L / ha or more, 500 L / ha or more, 1000 L / ha or more, 1500 L / ha or more, 2000 L / ha or more, 3000 L / ha or more, 4000 L / ha or more, 5000 L / ha or more, 7000 L / ha or more, 10,000 L / ha or more, 30,000 L / ha or more, 50,000 L / ha or more, 70,000 L / ha or more, 100,000 L / ha or more, 150,000 L / ha or more, 200,000 L / ha or more, 300,000 L / ha or more, 500,000 L / ha or more, or 750,000 L / ha or more. The amount may be 1,000,000 L / ha or more, 1,000,000 L / ha or less, 750,000 L / ha or less, 500,000 L / ha or less, 300,000 L / ha or less, 200,000 L / ha or less, 150,000 L / ha or less, 100,000 L / ha or less, 70,000 L / ha or less, 50,000 L / ha or less, 30,000 L / ha or less, 10,000 L / ha or less, 9000 L / ha or less, 8000 L / ha or less, 7000 L / ha or less, 6000 L / ha or less, 5000 L / ha or less, 4000 L / ha or less, 3000 L / ha or less, 2000 L / ha or less, or 1500 L / ha or less, or any combination thereof that is not contradictory. Specific examples of the application rate of the composition of the present invention in liquid form (e.g., a liquid composition of the present invention containing the active ingredient at a use concentration such as those exemplified above) may be 100 L / ha to 1500 L / ha, 1500 L / ha to 5000 L / ha, 5000 L / ha to 10,000 L / ha, 10,000 L / ha to 30,000 L / ha, 30,000 L / ha to 50,000 L / ha, 50,000 L / ha to 100,000 L / ha, 100,000 L / ha to 150,000 L / ha, 150,000 L / ha to 200,000 L / ha, 200,000 L / ha to 500,000 L / ha, or 500,000 L / ha to 10,000,000 L / ha.Specifically, the application rate of the composition of the present invention in liquid form (for example, a liquid composition of the present invention containing the active ingredient at a use concentration such as those exemplified above) may be, for example, 100 L / ha to 1,000,000 L / ha, 200 L / ha to 1,000,000 L / ha, 500 L / ha to 1,000,000 L / ha, 1000 L / ha to 750,000 L / ha, 10,000 L / ha to 750,000 L / ha, or 100,000 L / ha to 750,000 L / ha.

[0088] Furthermore, the application rate of the composition of the present invention can be determined taking into consideration not only the application area (two-dimensional factors) but also three-dimensional factors. That is, the application rate of the composition of the present invention can be determined, for example, depending on the height of the plants to which the composition of the present invention is applied (e.g., sprayed). Specifically, the application rate of the composition of the present invention in liquid form (e.g., a liquid composition of the present invention containing the active ingredient at a use concentration as exemplified above) for plants from ground level to knee height may be 1000 L / ha to 750,000 L / ha, 1000 L / ha to 30,000 L / ha, 1000 L / ha to 5000 L / ha, or 1000 L / ha to 1500 L / ha. Specifically, the application rate of the composition of the present invention may be, for example, as the application rate of the composition of the present invention in liquid form (for example, the composition of the present invention in liquid form containing the active ingredient at the use concentration as exemplified above), 1500 L / ha to 750,000 L / ha, 1500 L / ha to 70,000 L / ha, 1500 L / ha to 10,000 L / ha, or 1500 L / ha to 3000 L / ha for plants that are knee-high to human height. Specifically, the application rate of the composition of the present invention may be, for example, as the application rate of the composition of the present invention in liquid form (for example, a liquid composition of the present invention containing the active ingredient at a use concentration as exemplified above), 3000 L / ha to 750,000 L / ha, 3000 L / ha to 100,000 L / ha, 3000 L / ha to 30,000 L / ha, or 3000 L / ha to 5000 L / ha for plants up to 2 meters tall. Specifically, the application rate of the composition of the present invention may be, for example, as the application rate of the composition of the present invention in liquid form (for example, a composition of the present invention in liquid form containing the active ingredient at the use concentration as exemplified above), for plants of 2 meters or more, 5000 L / ha to 750,000 L / ha, 5000 L / ha to 150,000 L / ha, 5000 L / ha to 30,000 L / ha, or 5000 L / ha to 7000 L / ha.

[0089] When the composition of the present invention is applied to a growing medium (for example, by irrigation to the ground surface), the application rate of the composition of the present invention may be, for example, 250,000 L / ha to 750,000 L / ha as the application rate of the composition of the present invention in liquid form (for example, the composition of the present invention in liquid form containing the active ingredient at the use concentration as exemplified above).

[0090] The composition of the present invention may be applied only once or may be applied in multiple portions.The composition of the present invention may be applied, for example, in two or more portions, three or more portions, five or more portions, or ten or more portions.When the composition of the present invention is applied in multiple portions, the "application amount of the composition of the present invention" means the total application amount of the composition of the present invention by multiple applications.

[0091] The application amount of the composition of the present invention can be set, for example, so that the application amount of each active ingredient falls within a predetermined range.

[0092] 10 µmol / ha, 20 µmol / ha, 50 µmol / ha, 100 µmol / ha, 200 µmol / ha µmol / ha, 500 µmol / ha, 1 mmol / ha, 2 mmol / ha, 5 mmol / ha, 10 mmol / ha, 20 mmol / ha, 50 mmol / ha, 100 mmol / ha, 200 mmol / ha, 500 mmol / ha, 1 mol / ha, 2 mol / ha, 5 mol / ha, 10 mol / ha, 20 mol / ha, 50 mol / ha, 100 mol / ha, 200 mol / ha, 500 mol / ha mol / ha, 200 mol / ha, 100 mol / ha, 50 mol / ha, 20 mol / ha, 10 mol / ha, 5 mol / ha, 2 mol / ha, 1 mol / ha, 500 mmol / ha, 200 mmol / ha, 100 mmol / ha, 50 mmol / ha, 20 mmol / ha, 10 mmol / ha mmol / ha, 5 mmol / ha, 2 mmol / ha, 1 mmol / ha, 500 μmol / ha, 200 μmol / ha, 100 μmol / ha, 50 20 μmol / ha µmol / ha of 100 μmol / ha, 100,000,000 square meters, 100,000 mSpecifically, the application amount of component (A) is, for example, 10 μmol / ha to 20 μmol / ha, 20 μmol / ha to 50 μmol / ha, 50 μmol / ha to 100 μmol / ha, 100 μmol / ha to 200 μmol / ha, 200 μmol / ha to 500 μmol / ha, 500 μmol / ha to 1 mmol / ha, 1 mmol / ha to 2 mmol / ha, 2 mmol / ha to 5 mmol / ha, 5 mmol / ha to 10 mmol / ha, 10 mmol / ha to 20 mmol / ha, 20 mmol / ha to 50 mmol / ha, 50 mmol / ha to 100 mmol / ha, 100 mmol / ha to 200 mmol / ha, 200 mmol / ha to 500 mmol / ha, 500 mmol / ha to 1 mol / ha, 1 mol / ha to 2 mol / ha, 2 mol / ha to 5 mol / ha, 5 mol / ha to 10 The application rate may be 10 mol / ha, 10 mol / ha to 20 mol / ha, 20 mol / ha to 50 mol / ha, 50 mol / ha to 100 mol / ha, 100 mol / ha to 200 mol / ha, or 200 mol / ha to 500 mol / ha. When two or more types of component (A) are used, the application rates of those two or more types of component (A) may be set independently or in total within the range of the application rate of component (A) exemplified above. However, when two or more types of component (A) are used, unless otherwise specified, the "application rate of component (A)" refers to the total application rate of those two or more types of component (A). When the composition of the present invention is applied in multiple applications, the "application rate of component (A)" refers to the total application rate of component (A) from the multiple applications.

[0093] When at least component A1 is used as component (A), the application rate of component A1 may be, for example, 500 mmol / ha or more, 1 mol / ha or more, 2 mol / ha or more, 5 mol / ha or more, 10 mol / ha or more, 20 mol / ha or more, 50 mol / ha or more, 100 mol / ha or more, or 200 mol / ha or more, or 500 mol / ha or less, 200 mol / ha or less, 100 mol / ha or less, 50 mol / ha or less, 20 mol / ha or less, 10 mol / ha or less, 5 mol / ha or less, 2 mol / ha or less, or 1 mol / ha or less, or any compatible combination thereof. The application rate of component A1 may be, for example, 500 mmol / ha to 1 mol / ha, 1 mol / ha to 2 mol / ha, 2 mol / ha to 5 mol / ha, 5 mol / ha to 10 mol / ha, 10 mol / ha to 20 mol / ha, 20 mol / ha to 50 mol / ha, 50 mol / ha to 100 mol / ha, 100 mol / ha to 200 mol / ha, or 200 mol / ha to 500 mol / ha. The application rate of component A1 may be, for example, 500 mmol / ha to 500 mol / ha, 1 mol / ha to 100 mol / ha, or 2 mol / ha to 20 mol / ha. When two or more types of component A1 are used, the application rates of the two or more types of component A1 may be set independently or in total within the range of the application rate of component A1 exemplified above. However, when two or more kinds of component A1 are used, the term "application amount of component A1" means the total application amount of those two or more kinds of component A1, unless otherwise specified. When the composition of the present invention is applied in multiple applications, the term "application amount of component A1" means the total application amount of component A1 in multiple applications.

[0094] When at least component A2 is used as component (A), the application rate of component A2 may be, for example, 10 μmol / ha or more, 20 μmol / ha or more, 50 μmol / ha or more, 100 μmol / ha or more, 200 μmol / ha or more, 500 μmol / ha or more, 1 mmol / ha or more, 2 mmol / ha or more, 5 mmol / ha or more, 10 mmol / ha or more, or 20 mmol / ha or more, 50 mmol / ha or less, 20 mmol / ha or less, 10 mmol / ha or less, 5 mmol / ha or less, 2 mmol / ha or less, 1 mmol / ha or less, 500 μmol / ha or less, 200 μmol / ha or less, 100 μmol / ha or less, 50 μmol / ha or less, or 20 μmol / ha or less, or a compatible combination thereof. Specifically, the application amount of component A2 is, for example, 10 μmol / ha to 20 μmol / ha, 20 μmol / ha to 50 μmol / ha, 50 μmol / ha to 100 μmol / ha, 100 μmol / ha to 200 μmol / ha, 200 μmol / ha to 500 μmol / ha, 500 μmol / ha to 1 mmol / ha, 1 mmol / ha to 2 mmol / ha, 2 It may be mmol / ha to 5 mmol / ha, 5 mmol / ha to 10 mmol / ha, 10 mmol / ha to 20 mmol / ha, or 20 mmol / ha to 50 mmol / ha. Specifically, the application amount of component A2 may be, for example, 10 μmol / ha to 10 mmol / ha, 20 μmol / ha to 5 mmol / ha, or 50 μmol / ha to 2 mmol / ha. When two or more kinds of component A2 are used, the application amounts of the two or more kinds of component A2 may be set independently or in total within the range of the application amount of component A2 exemplified above. However, when two or more kinds of component A2 are used, the "application amount of component A2" means the total application amount of the two or more kinds of component A2 unless otherwise specified. When the composition of the present invention is applied in multiple applications, the "application amount of component A2" means the total application amount of component A2 in multiple applications.

[0095] When at least component A3 is used as component (A), the application rate of component A3 may be, for example, 1 mmol / ha or more, 2 mmol / ha or more, 5 mmol / ha or more, 10 mmol / ha or more, 20 mmol / ha or more, 50 mmol / ha or more, 100 mmol / ha or more, 200 mmol / ha or more, or 500 mmol / ha or more, or 1 mol / ha or less, 500 mmol / ha or less, 200 mmol / ha or less, 100 mmol / ha or less, 50 mmol / ha or less, 20 mmol / ha or less, 10 mmol / ha or less, 5 mmol / ha or less, or 2 mmol / ha or less, or a compatible combination thereof. The application rate of component A3 may be, for example, 1 mmol / ha to 2 mmol / ha, 2 mmol / ha to 5 mmol / ha, 5 mmol / ha to 10 mmol / ha, 10 mmol / ha to 20 mmol / ha, 20 mmol / ha to 50 mmol / ha, 50 mmol / ha to 100 mmol / ha, 100 mmol / ha to 200 mmol / ha, 200 mmol / ha to 500 mmol / ha, or 500 mmol / ha to 1 mol / ha. The application rate of component A3 may be, for example, 1 mmol / ha to 200 mmol / ha, 2 mmol / ha to 100 mmol / ha, or 5 mmol / ha to 50 mmol / ha. When two or more types of component A3 are used, the application rates of those two or more types of component A3 may be set independently or in total within the range of the application rate of component A3 exemplified above. However, when two or more kinds of component A3 are used, the "application amount of component A3" means the total application amount of those two or more kinds of component A3, unless otherwise specified. When the composition of the present invention is applied in multiple applications, the "application amount of component A3" means the total application amount of component A3 in multiple applications.

[0096] The application rate of component (B) may be, for example, 1 mmol / ha or more, 2 mmol / ha or more, 5 mmol / ha or more, 10 mmol / ha or more, 20 mmol / ha or more, 50 mmol / ha or more, 100 mmol / ha or more, 200 mmol / ha or more, or 500 mmol / ha or more, or 1 mol / ha or less, 500 mmol / ha or less, 200 mmol / ha or less, 100 mmol / ha or less, 50 mmol / ha or less, 20 mmol / ha or less, 10 mmol / ha or less, 5 mmol / ha or less, or 2 mmol / ha or less, or any compatible combination thereof. The application rate of component (B) may be, for example, 1 mmol / ha to 2 mmol / ha, 2 mmol / ha to 5 mmol / ha, 5 mmol / ha to 10 mmol / ha, 10 mmol / ha to 20 mmol / ha, 20 mmol / ha to 50 mmol / ha, 50 mmol / ha to 100 mmol / ha, 100 mmol / ha to 200 mmol / ha, 200 mmol / ha to 500 mmol / ha, or 500 mmol / ha to 1 mol / ha. The application rate of component (B) may be, for example, 1 mmol / ha to 1 mol / ha, 2 mmol / ha to 200 mmol / ha, or 5 mmol / ha to 50 mmol / ha. When two or more types of component (B) are used, the application rates of those two or more types of component (B) may be set independently or in total within the range of the application rate of component (B) exemplified above. However, when two or more kinds of component (B) are used, unless otherwise specified, the "application amount of component (B)" means the total application amount of those two or more kinds of component (B). When the composition of the present invention is applied in multiple divided applications, the "application amount of component (B)" means the total application amount of component (B) in multiple applications.

[0097] The application amount of the composition of the present invention as exemplified above may be the application amount when the composition of the present invention is applied to a plant by spraying it onto a plant body, such as by foliar spraying, or by spraying it onto a medium in which the plant is cultivated.

[0098] The above-mentioned description of the application mode of the composition of the present invention can be applied mutatis mutandis to any other case in which an active ingredient is applied to a plant. That is, the active ingredient may be applied to a plant, for example, at a use concentration such as those exemplified above. Also, the active ingredient may be applied to a plant, for example, at an application rate of the active ingredient such as those exemplified above. Also, the active ingredient may be prepared as a composition, such as a liquid composition, containing the active ingredient and applied to a plant. The description of the composition of the present invention can be applied mutatis mutandis to a composition containing an active ingredient. The active ingredient can be applied to a plant, particularly in liquid form. That is, specifically, the active ingredient may be prepared as a liquid composition containing the active ingredient at a use concentration such as those exemplified above and applied to a plant. The active ingredients may be applied to a plant in a pre-mixed state, or each may be applied to a plant separately. That is, for example, a composition, such as a liquid composition, containing both component (A) and component (B) can be prepared and applied to a plant. Alternatively, for example, a composition such as a liquid composition containing component (A) and a composition such as a liquid composition containing component (B) can be prepared separately and applied to plants. The active ingredient may also be used in combination with other ingredients such as a wetting agent.

[0099] Plant cultivation may be carried out under high-temperature stress conditions. Cultivating plants under high-temperature stress conditions is also referred to as "exposing plants to high-temperature stress" or "treating plants to high temperatures." Plant cultivation may be carried out under high-temperature stress conditions for the entire period or only a portion of the period. "Plant cultivation under high-temperature stress conditions" means that plant cultivation is carried out under high-temperature stress conditions for at least a portion of the period, and does not necessarily require plant cultivation to be carried out under high-temperature stress conditions for the entire period. "High-temperature stress conditions" may refer to conditions under which high-temperature stress symptoms are induced in plants when an active ingredient is not used. Examples of high-temperature stress conditions include conditions under which plants are cultivated at temperatures higher than the normal cultivation temperature for plants, and in which growth is worse than when the plant is cultivated at the normal cultivation temperature when an active ingredient is not used. "Growth is impaired" may mean, for example, that the degree of growth (e.g., growth amount or growth rate) of a plant grown under high temperature stress conditions is reduced to 90% or less, 70% or less, 50% or less, 30% or less, 20% or less, or 10% or less compared to when the plant is grown at a normal cultivation temperature, and also includes cases where no growth of the plant is observed at all. The cultivation temperature for a plant under high temperature stress conditions may be, for example, 3 to 20°C, 5 to 15°C, or 7 to 12°C higher than the normal cultivation temperature for the plant. Normal cultivation temperatures for plants include the optimum temperature for plant growth. The high temperature treatment may be carried out only once, or may be carried out intermittently two or more times. The high temperature treatment may be carried out intentionally or unintentionally. The high temperature treatment may usually be carried out unintentionally. For example, high temperature stress conditions may be naturally achieved depending on the natural environment, such as weather or season, thereby carrying out the high temperature treatment unintentionally.

[0100] The period of high-temperature treatment per session or in total may be, for example, 3 hours or more, 6 hours or more, 12 hours or more, 1 day or more, 2 days or more, 3 days or more, 5 days or more, 7 days or more, 10 days or more, 15 days or more, 20 days or more, or 30 days or more, or 50 days or less, 30 days or less, 20 days or less, 15 days or less, 10 days or less, 7 days or less, 5 days or less, 3 days or less, 2 days or less, 1 day or less, 12 hours or less, or 6 hours or less, or any combination thereof that is not inconsistent. The period of high-temperature treatment per session or in total may be, for example, 3 hours to 6 hours, 6 hours to 12 hours, 12 hours to 1 day, 1 day to 2 days, 2 days to 3 days, 3 days to 5 days, 5 days to 7 days, 7 days to 10 days, 10 days to 15 days, 15 days to 20 days, 20 days to 30 days, or 30 days to 50 days.

[0101] Furthermore, the high-temperature treatment may be carried out continuously or intermittently for a predetermined number of days for a predetermined period of time per day. The predetermined period of time may be, for example, 1 hour or more, 3 hours or more, 6 hours or more, 9 hours or more, or 12 hours or more per day, or 18 hours or less, 12 hours or less, 9 hours or less, 6 hours or less, or 3 hours or less per day, or any combination thereof that is not inconsistent. Specifically, the predetermined period of time may be, for example, 1 to 3 hours, 3 to 6 hours, 6 to 9 hours, 9 to 12 hours, or 12 to 18 hours per day. Specifically, the predetermined period of time may be, for example, 1 to 12 hours or 3 to 6 hours per day. The predetermined number of days may be, for example, 1 day or more, 2 days or more, 3 days or more, 5 days or more, 7 days or more, 10 days or more, 15 days or more, 20 days or more, or 30 days or more, or 50 days or less, 30 days or less, 20 days or less, 15 days or less, 10 days or less, 7 days or less, 5 days or less, 3 days or less, or 2 days or less, or any compatible combination thereof. Specifically, the predetermined number of days may be, for example, 1 to 50 days, 3 to 20 days, or 5 to 15 days.

[0102] Note that a plant (specifically, a plant body) can be obtained by cultivating a plant using the method of the present invention. Therefore, one embodiment of the method of the present invention may be a method for producing a plant (specifically, a plant body). More specifically, one embodiment of the method of the present invention may be a method for producing a plant (specifically, a plant body) comprising applying active ingredients (i.e., the above-mentioned components (A) and (B)) to a plant and cultivating the plant. The method for cultivating a plant is not particularly limited. Plant cultivation can be carried out, for example, by the same method as a conventional method for cultivating plants, except for the application of the active ingredients. The plant cultivation method is as described above. The plant (specifically, a plant body) can be harvested as appropriate. That is, the method of the present invention may further include harvesting the plant (specifically, a plant body). "Harvesting" may be used interchangeably with "recovery." "Harvesting or recovering a plant" may be used interchangeably with "harvesting or recovering a plant body." The harvested plant (specifically, a plant body) may be the entire plant body or a part of the plant body. Examples of parts of the plant body include leaves, stems, trunks, roots, fruits, and seeds. Plant parts include, in particular, fruits.

[0103] <5> Use of Active Ingredient The present invention also discloses the use of the active ingredient in the above-exemplified applications. That is, the present invention discloses, for example, the use of the active ingredient for inducing heat stress tolerance in plants, and the use of the active ingredient in the production of a composition for inducing heat stress tolerance in plants.

[0104] The present invention also discloses active ingredients for use in the above-exemplified applications. That is, the present invention discloses, for example, active ingredients for use in inducing high temperature stress tolerance in plants and active ingredients for use in producing a composition for inducing high temperature stress tolerance in plants.

[0105] The present invention also discloses the use of each active ingredient in combination with other active ingredients. That is, the present invention discloses, for example, the use of component (A) in combination with component (B), or the use of component (B) in combination with component (A). Each active ingredient may be used in combination with other active ingredients for the uses exemplified above.

[0106] The present invention will be described in more detail below with reference to non-limiting examples. Valine (Val) used in the following experiments is L-valine.

[0107] Example 1 Evaluation of the effect of Val, IAA, and Val & IAA in inducing high temperature stress tolerance In this example, Val (valine) and IAA (indole-3-acetic acid) were applied alone or in combination to tomatoes, and the effect of inducing high temperature stress tolerance was evaluated.

[0108] Experimental materials: Tomato: variety Regina

[0109] Plant cultivation Two tomato seeds were sown in a 10.5 cm diameter pot (Sakata) containing 350 g of a mixture of potting soil (Combination No. 1) and vermiculite (potting soil:vermiculite = 3:1 (v:v)). After two weeks, the tomato plants were thinned out, leaving only one plant. The tomato plants were grown in a Biotron under the temperature and light conditions shown in Table 2. 35 days after sowing, soil fertilization was carried out with 100 mL of 500-fold diluted Hyponex solution. Watering was carried out at the appropriate time.

[0110] Six treatments, as shown in Table 1, were evaluated. The non-heat stress + water treatment (No. 1) served as the positive control. The heat stress treatment included five treatments (Nos. 2–6). The tomato plant growth stages and cultivation conditions are shown in Table 2. The treatments and heat treatments were divided into two sets. The first treatment was performed 40 days after sowing, when the tomato plants had begun to flower. The second treatment was performed 46 days after sowing. The treatments were performed by foliar spray using an aqueous solution containing 0.1% Approach BI as a wetting agent. 6 mL of the aqueous solution was sprayed per tomato plant. The heat treatment began 24 hours after treatment and continued for five days in each set. The heat treatment was performed under conditions similar to those observed in nature, gradually increasing to a maximum of 35°C and then gradually decreasing. After the second set of high temperature treatments was completed, the tomato plants were grown at room temperature for an additional 14 days.

[0111]

[0112]

[0113] Fruit survey The number of tomato fruits was surveyed from the time of the first set of material treatment until the completion of cultivation.

[0114] Results and Discussion Figure 1 shows the appearance of tomato plants just before harvest. Figure 2 shows the harvested tomato fruits. Figure 3 shows the cumulative number of tomato fruits. There were no significant differences in the appearance of tomato plants among the treatments (Figure 1). However, compared with the non-high temperature stress + water treatment (No. 1), the number of tomato fruits in the high temperature stress + water treatment (No. 2) was significantly reduced (Figure 2). This result suggests that high temperature treatment significantly damaged tomatoes. Compared with the high temperature stress + water treatment (No. 2), the number of tomato fruits in the high temperature stress + Val and / or IAA treatment (No. 3-6) treatments was significantly increased (Figure 2). In particular, the number of tomato fruits increased most significantly in the high temperature stress + Val and IAA treatment (No. 6), demonstrating a synergistic effect of Val and IAA (Figure 2). Furthermore, there were no significant differences in the timing of fruit increase among the treatments (Figure 3). At all cultivation stages, the number of tomato fruits was highest in the non-high temperature stress + water treatment group (No. 1), followed by the high temperature stress + Val and IAA treatment group (No. 6), and the lowest in the high temperature stress + water treatment group (No. 2). These results suggest that the combined use of substances that alter plant amino acid metabolism, such as Val, and substances with auxin-like activity, such as IAA, can significantly induce high temperature stress tolerance in plants.

[0115] Example 2 Evaluation of the effect of Val, PAA, and Val & PAA in inducing high temperature stress tolerance In this example, Val (valine) and PAA (phenylacetic acid) were applied alone or in combination to tomatoes, and the effect of inducing high temperature stress tolerance was evaluated.

[0116] Experimental materials: Same as in Example 1.

[0117] Plant cultivation: Same as in Example 1.

[0118] Treatment of materials and high temperature treatment The same as in Example 1, except that the five treatment plots shown in Table 3 were evaluated under the cultivation conditions shown in Table 4 (maximum high temperature: 37°C).

[0119]

[0120]

[0121] Fruit survey: Same as Example 1.

[0122] Results and Discussion: The number and weight of harvested tomato fruits are shown in Figures 4 and 5, respectively. Compared with the non-heat-stressed + water-treated group (No. 1), the number of tomato fruits in the heat-stressed + water-treated group (No. 2) was significantly reduced (Figure 4). This result suggests that high temperature treatment significantly damaged tomatoes. Compared with the heat-stressed + water-treated group (No. 2), there was no significant difference in the number of tomato fruits in the heat-stressed + Val or PAA-treated group (No. 3-4). On the other hand, compared with the heat-stressed + water-treated group (No. 2), the number of tomato fruits in the heat-stressed + Val and PAA-treated group (No. 5) significantly increased, demonstrating a synergistic effect of Val and PAA. A correlation was observed between the number and weight of tomato fruits (Figures 3-4). These results suggest that the combined use of substances that alter plant amino acid metabolism, such as Val, and substances with auxin-like activity, such as PAA, can significantly induce high temperature stress tolerance in plants.

[0123] Example 3 Evaluation of High Temperature Stress Tolerance Genes Experimental Materials Tomato plants (variety: Regina) were used for gene evaluation.

[0124] Plant cultivation and material treatment Two tomato seeds were sown in a 10.5 cm diameter slit pot (10.5 cm diameter x 8.8 cm height) filled with potting soil and cultivated in a biotron at 23°C with a 14 hour light period (6:00 to 20:00) and 10 hour dark period (20:00 to 6:00). The potting soil used was a 3:1 (volume ratio) mixture of Kumiai Nippi Engei Baido No. 1 (Nihon Hiryo Co., Ltd.) and vermiculite. After one week, the plants were thinned out, leaving only one plant, and cultivation continued.

[0125] The materials were dissolved in water before use. 25 days after sowing, 0.1% Approach BI (Kao Corporation) wetting agent was added to the treatment solution and sprayed over the entire plant. The treatment groups are shown in Table 5. Three tomato plants were used for each treatment group, and 2 mL of the treatment solution was sprayed per plant. 24 hours after spraying, a 1.5 cm x 1.5 cm square sample was collected from the second true leaf.

[0126]

[0127] Gene expression analysis: Maxwell TM RNA was extracted using the RSC Plant RNA Kit (Promega) according to the kit's instructions. TM Single-stranded cDNA was synthesized from the extracted RNA using qPCR RT Master Mix (TOYOBO). Two genes related to high temperature stress tolerance in tomato were evaluated: Heat shock factor A2 (HsFA2) and ascorbate peroxidases (APX).

[0128] Using the above cDNA as a template, real-time PCR was carried out using the primers shown in Table 6, and the expression level of each gene was calculated as a relative expression level to the actin gene.

[0129]

[0130] Results The results are shown in Figure 6 (n=3). Compared to the mock water control, no significant difference in the expression of SLHsfA2 or SLAPX was observed with Val, IAA, or PAA alone, but the combinations Val&IAA and Val&PAA promoted the expression of both genes. These results suggest that the combinations Val&IAA and Val&PAA are effective in improving heat stress tolerance.

[0131] Example 4 Tomato pot test Experimental materials Tomato: Home Momotaro, rootstock (Volante)

[0132] Plant Cultivation and Processing Methods 0.18m 2A planter was filled with sandy loam (SL) and two tomato plants were planted. The fertilizer used was OK-F-1 (OAT Agrio Co., Ltd.), diluted 2,000 times with water and applied at 2,000 mL per plant per application. The tops were pinched off, leaving one leaf on the fourth inflorescence, and side shoots were removed as needed. Cultivation took place in a greenhouse exposed to natural light.

[0133] Five treatments were evaluated for high temperature and material treatments (Table 7). The water treatment, a non-high temperature stress treatment, served as a positive control. The other four treatments were high temperature treatments. High temperature treatments were carried out twice, once for 10 days before the first inflorescence had bloomed and again for 10 days after the fourth inflorescence had bloomed. High temperature treatments (maximum temperature within the facility of 35°C) were carried out by opening and closing the side windows and skylights of the greenhouse.

[0134] The materials were sprayed on the foliage at 50 mL per plant on the day the high-temperature treatment started and three days later. A wetting agent (Approach BI (Kao)) was added to each material to a final concentration of 0.05%.

[0135]

[0136] Fruit survey Harvesting and surveys were carried out 11 times until the fourth inflorescence matured.

[0137] Results and Discussion Fruit harvesting and investigation were carried out 11 times until the fourth inflorescence matured.

[0138] The average maximum temperature during the first stress treatment period was 29.8°C for the non-heat-stressed area and 33.2°C for the heat-stressed area. During the second treatment, the average maximum temperature was 30.8°C for the non-heat-stressed area and 34.3°C for the heat-stressed area.

[0139] Figure 7 shows the fruit harvest weight for each treatment. Fruit harvest weight in the water sprayed high-temperature stress treatment was lower than in the non-high-temperature stressed treatment, suggesting that high-temperature stress had been applied. Among the high-temperature stress treatments, the PAA 10 μM + Val 5 mM treatment had the highest fruit harvest weight, exceeding even the non-high-temperature stressed treatment. This was followed by the PAA 10 μM and Val 5 mM treatments, both of which exceeded the water spray treatment.

[0140] Figure 8 shows the fruit Brix for each treatment. No clear differences were observed between treatments. Generally, fruit yield and Brix are in a trade-off relationship, with Brix decreasing as yield increases. However, the materials used in this test were able to increase yield without decreasing Brix.

[0141] The above evaluation results showed that the combination of Val and PAA significantly reduced or increased yield compared to water treatment or treatment with Val or PAA alone, and was effective as a material for improving high temperature stress tolerance.

[0142] Example 5 Rice pot test Experimental materials Rice variety: Nipponbare

[0143] Plant Cultivation and Material Treatment Sowing and Planting of Rice Before sowing, rice seeds were sterilized with 25% antiformin and 70% ethanol. Rice seeds were placed on filter paper in a petri dish, the filter paper was thoroughly wetted with sterilized water, and germinated in the dark at 25°C. Six days after sowing, the germinated rice seeds were planted in cell trays. The culture medium in the cell trays was a mixture of Kumiai-bai-do No. 1 and vermiculite at a ratio of 7:3 (V / V). The rice plants planted in the cell trays were grown in a chamber under the following conditions: 28°C, 14 h light, 22°C, 10 h dark.

[0144] Rice cultivation and material treatment On June 20th, rice seedlings grown in a chamber for 18 days were transplanted into magnetic pots and grown in an outdoor cultivation tank until harvest. 2.3 kg of potting soil (Kumiai-hitsuji No. 1: vermiculite = 7:3 (V / V)) was used in the magnetic pots, and two rice seedlings were transplanted per pot. Water was managed appropriately during cultivation, and starting one month after transplanting, ammonium sulfate and Hyponex were fertilized three times at weekly intervals.

[0145] Rice plants were sprayed twice at one-week intervals during the heading stage, one week after the onset of heading, and then subjected to high-temperature treatment. The high-temperature treatment was initiated approximately 16 hours after spraying. The treatment groups are shown in Table 8. Each treatment group consisted of five replicate pots. The treatment solution was prepared by diluting the materials with water, and 0.1% Approach BI (Kao Corporation) wetting agent was added to the treatment solution. 60 mL of the solution was sprayed over the entire plant per pot. The high-temperature treatment was performed for six hours between 10:00 and 16:00, with the rice plants placed in a mini greenhouse at a temperature of approximately 37°C to 39°C. After the high-temperature treatment, the plants were cultivated and harvested by cutting the above-ground parts on October 8, 50 days after transplanting them into Wagner pots.

[0146]

[0147] After drying the above-ground parts of the plants, including the excised seeds, for 15 days, the total seed weight, fertile seed weight, and fertility were measured. The fertile seed weight was the weight of the seeds after empty, sterile seeds were removed using a thresher. 10 mL of seeds (approximately 100-150 seeds) were randomly taken from the total seeds and placed in a 50 mL Falcon tube. Fertile and sterile seeds were separated and counted, and the percentage of fertile seeds relative to the total number of seeds was used to determine fertility.

[0148] Results and Discussion Figure 9 and Table 9 show the results for total seed weight, fertile seed weight, and seed fertility. Compared to the treatment without high temperature stress, all three parameters shown in the figure were lower in each treatment with high temperature stress, suggesting damage from the high temperature. Under high temperature treatment, total seed weight and fertile seed weight were not significantly different from the water treatment for either Val or PAA alone, but the combination of Val and PAA increased seed fertility by 8.5% and 17.7%, respectively. Both Val and PAA alone and the combination of both increased seed fertility, with PAA alone and the combination of Val and PAA increasing seed fertility by more than 20%.

[0149] Under high temperature conditions, the combination of Val and PAA increased rice total seed weight, fertile seed weight, and seed fertility compared to the control water treatment, suggesting that the combination of Val and PAA was effective in reducing high-temperature damage to rice seed formation and growth and improving high-temperature tolerance.

[0150]

Claims

1. A composition for inducing high temperature stress tolerance in a plant, comprising the following components (A) and (B): (A) a substance having the property of changing the amino acid metabolism of a plant; (B) a substance having auxin-like activity.

2. The composition according to claim 1, wherein the component (A) is the following components (A1), (A2), (A3), or a combination thereof: (A1) one or more components selected from the group consisting of branched-chain amino acids and intermediates in their biosynthetic and consumption pathways; (A2) a substance having inhibitory activity against acetolactate synthase; (A3) a substance having inhibitory activity against 5-enolpyruvylshikimate-3-phosphate synthase.

3. The composition according to claim 2, wherein the component (A1) is one or more components selected from the group consisting of pyruvic acid, ketobutyric acid, acetolactic acid, acetohydroxybutyric acid, 2,3-dihydroxyisovaleric acid, 2,3-dihydroxy-3-methylvaleric acid, α-ketoisovaleric acid, ketomethylvaleric acid, 2-isopropylmalic acid, 3-isopropylmalic acid, ketoisocaproic acid, valine, leucine, isoleucine, and derivatives thereof.

4. The composition according to claim 2, wherein said component (A1) is one or more components selected from the group consisting of valine, leucine, and α-ketoisovaleric acid.

5. The composition of claim 2, wherein the branched chain amino acid is in the L-configuration.

6. The composition according to claim 2, wherein the component (A2) is one or more components selected from the group consisting of sulfonylurea compounds, imidazoline compounds, pyrimidinylsalicylic acid compounds, triazolopyrimidine sulfonamide compounds, pyrimidinyl (thio)benzoate compounds, sulfonanilide compounds, and sulfonylaminocarbonyltriazolinone compounds.

7. The composition according to claim 2, wherein the component (A3) is glyphosate.

8. The composition of claim 1 or 2, wherein component (B) is one or more components selected from the group consisting of indole-3-acetic acid, 4-chloroindole-3-acetic acid, 2,4-dichlorophenoxyacetic acid, 2,4,5-trichlorophenoxyacetic acid, naphthaleneacetic acid, naphthoxyacetic acid, phenylacetic acid, and analogs thereof.

9. The composition of claim 1, wherein said component (B) is one or more components selected from the group consisting of indole-3-acetic acid and phenylacetic acid.

10. The composition according to claim 2, which is used in the form of a liquid containing the component (A1) at a concentration of 200 μM to 200 mM.

11. The composition according to claim 2, which is used in the form of a liquid containing the component (A2) at a concentration of 5 nM to 5 μM.

12. The composition according to claim 2, which is used in the form of a liquid containing the component (A3) at a concentration of 500 nM to 100 μM.

13. The composition according to claim 1 or 2, which is used in the form of a liquid containing the component (B) at a concentration of 500 nM to 500 μM.

14. The composition according to claim 1 or 2, wherein the induction of high temperature stress resistance is the alleviation of high temperature stress symptoms.

15. The composition according to claim 14, wherein the relief of the high temperature stress symptoms is an increase in plant yield.

16. The composition according to claim 1 or 2, wherein the plant is a grass, a solanaceae, a cucurbit, a legume, a cruciferous, a rose, a mulberry, a mallow, a parsley, a lily, a aster, a amaranth, an ericaceae, a vine, a citrus, a rubiaceae, an oleaceae, a laurel, a sycamore, a sanguinea, a sapindaceae, or a lamiaceae.

17. A method for inducing high temperature stress tolerance in a plant, comprising applying the following components (A) and (B) to the plant: (A) a substance having the property of changing the amino acid metabolism of the plant; (B) a substance having auxin-like activity.

18. A method for producing a plant body, comprising: cultivating the plant by applying the following components (A) and (B) to the plant; and harvesting the plant body: (A) a substance having the property of changing the amino acid metabolism of the plant; (B) a substance having auxin-like activity.

19. The method according to claim 17 or 18, wherein the component (A) is the following components (A1), (A2), (A3), or a combination thereof: (A1) one or more components selected from the group consisting of branched-chain amino acids and intermediates in their biosynthetic and consumption pathways; (A2) a substance having inhibitory activity against acetolactate synthase; (A3) a substance having inhibitory activity against 5-enolpyruvylshikimate-3-phosphate synthase.

20. The method of claim 19, wherein the component (A1) is one or more components selected from the group consisting of pyruvic acid, ketobutyric acid, acetolactic acid, acetohydroxybutyric acid, 2,3-dihydroxyisovaleric acid, 2,3-dihydroxy-3-methylvaleric acid, α-ketoisovaleric acid, ketomethylvaleric acid, 2-isopropylmalic acid, 3-isopropylmalic acid, ketoisocaproic acid, valine, leucine, isoleucine, and derivatives thereof.

21. The method of claim 19, wherein said component (A1) is one or more components selected from the group consisting of valine, leucine, and α-ketoisovaleric acid.

22. The method of claim 19, wherein the branched chain amino acid is in the L-configuration.

23. The method according to claim 19, wherein the component (A2) is one or more components selected from the group consisting of sulfonylurea compounds, imidazoline compounds, pyrimidinyl salicylic acid compounds, triazolopyrimidine sulfonamide compounds, pyrimidinyl (thio)benzoate compounds, sulfonanilide compounds, and sulfonylaminocarbonyltriazolinone compounds.

24. The method of claim 19, wherein the component (A3) is glyphosate.

25. The method of claim 17 or 18, wherein component (B) is one or more components selected from the group consisting of indole-3-acetic acid, 4-chloroindole-3-acetic acid, 2,4-dichlorophenoxyacetic acid, 2,4,5-trichlorophenoxyacetic acid, naphthaleneacetic acid, naphthoxyacetic acid, phenylacetic acid, and analogs thereof.

26. The method of claim 17 or 18, wherein component (B) is one or more components selected from the group consisting of indole-3-acetic acid and phenylacetic acid.

27. The method according to claim 19, wherein the component (A1) is used in the form of a liquid containing the component (A1) at a concentration of 200 μM to 200 mM.

28. The method according to claim 19, wherein the component (A2) is used in the form of a liquid containing the component (A2) at a concentration of 5 nM to 5 μM.

29. The method according to claim 19, wherein the component (A3) is used in the form of a liquid containing the component (A3) at a concentration of 500 nM to 100 μM.

30. The method according to claim 17 or 18, wherein the component (B) is used in the form of a liquid containing the component (B) at a concentration of 500 nM to 500 μM.

31. The method according to claim 17 or 18, wherein the induction of high temperature stress resistance is the alleviation of high temperature stress symptoms.

32. The method of claim 31, wherein the reduction in the high temperature stress symptoms is an increase in plant yield.

33. The method of claim 17 or 18, wherein the plant is a grass, a solanaceae, a cucurbit, a legume, a cruciferous, a rose, a mulberry, a mallow, a parsley, a lily, a aster, an amaranth, an ericaceae, a citrus, a rubiaceae, an oleaceae, a laurel, a sycamore, a sanguinea, a sapindaceae, or a lamiaceae.