How to reduce or prevent the effects of salt stress on plants

Abstract

The present invention pertains to a method for reducing or preventing the effect of salt stress on a plant which involves applying at least one compound / salt selected from the group consisting of a compound represented by formula (I) and a salt thereof to a plant which has been exposed to salt stress or a plant for which there is a risk of salt stress exposure.　In formula (I), R represents a C1-6 alkyl group, X represents a halogen group, n represents the number of X and is any integer from 0-2, X may be the same as or different from one another when n is 2 or higher, Y represents a halogen group, m represents the number of Y and is any integer from 0-3, Y may be the same as or different from one another when m is 2 or higher, and Z represents a C1-8 alkyl group or a C1-8 alkoxy group.

Description

[Technical Field]

[0001] The present invention relates to a method for reducing or preventing the effects of salt stress on plants. This application claims priority to Japanese Patent Application No. 2022-34791, filed on March 7, 2022, the contents of which are incorporated herein by reference. [Background technology]

[0002] Salt stress refers to a state of repression or tension observed in cells or individuals under environmental conditions in which the salt concentration in the soil has shifted from the optimum concentration for growth to a higher concentration. Salt stress is caused by the accumulation of salts, such as sodium chloride, and is observed not only in coastal areas where seawater can flood or infiltrate, but also in arid regions and in saline soils artificially created by inappropriate irrigation. The effects of salt stress are most evident in the form of stunted growth and reduced productivity. There is a need to reduce or prevent the effects of salt stress on plants.

[0003] Incidentally, Patent Document 1 discloses a crop phytotoxicity safener containing hydroxyisoxazole or the like as an active ingredient. According to Patent Document 1, the phytotoxicity safener is a composition that is used in combination with agricultural materials or applied alone before or after the use of agricultural materials to reduce phytotoxicity when known or unknown undesirable phytotoxicity is expected to occur in crops when agricultural materials are used on cultivated crops to control weeds, diseases, or pests, such as growth impairment, growth inhibition, growth suppression, appearance of brown spots, tillering inhibition, yellowing, leaf wither, withering, wilting, bleaching, twisting, browning, root growth inhibition, etc.

[0004] Patent Document 2 discloses a plant growth promoter containing, as an active ingredient, a compound represented by formula (1-31), a compound represented by formula (2-13), or the like. [ka]

[0005] [ka]

[0006] Patent Document 3 discloses a plant disease control agent containing a compound represented by formula (1)-7 as an active ingredient. [ka] [Prior art documents] [Patent documents]

[0007] [Patent Document 1] WO 2019 / 163946 A1 [Patent Document 2] WO 2010 / 001563 A1 [Patent Document 3] WO 03 / 016303 A1 [Non-patent literature]

[0008] [Non-Patent Document 1] "Graphical representation of stereochemical configuration", Pure and Applied Chemistry 78, 1897-1970, 2006 IUPAC Summary of the Invention [Problem to be solved by the invention]

[0009] An object of the present invention is to provide a method for reducing or preventing the effects of salt stress on plants. [Means for solving the problem]

[0010] The present invention includes the following aspects.

[0011] [1] A method for reducing or preventing the effects of salt stress on a plant, comprising applying at least one compound selected from the group consisting of the compound represented by formula (I) and a salt thereof to a plant that is exposed to salt stress or that may be exposed to salt stress. [ka] [In formula (I), R represents a C1-6 alkyl group; X represents a halogeno group; n represents the number of Xs and is an integer of 0 to 2, and when n is 2 or greater, Xs may be the same or different; Y represents a halogeno group; m represents the number of Y's and is an integer of 0 to 3, and when m is 2 or more, Y's may be the same or different from each other; and Z represents a C1-8 alkyl group or a C1-8 alkoxy group.

[0012] [2] The method according to [1], wherein in formula (I), R is a methyl group, n is 0, m is 0, and Z is a t-butoxy group.

[0013] [3] The method according to [1] or [2], wherein the application to the plant is by spraying on the planted plant, drenching the soil in which the plant is planted, smearing on the seeds of the plant, or adding to the water medium in which the plant is planted.

[0014] [4] A composition for reducing or preventing the effects of salt stress on plants, comprising at least one selected from the group consisting of compounds represented by formula (I) and salts thereof.

[0015] [ka] [In formula (I), R represents a C1-6 alkyl group; X represents a halogeno group; n represents the number of Xs and is an integer of 0 to 2, and when n is 2 or greater, Xs may be the same or different; Y represents a halogeno group; m represents the number of Y's and is an integer of 0 to 3, and when m is 2 or more, Y's may be the same or different from each other; and Z represents a C1-8 alkyl group or a C1-8 alkoxy group.

[0016] [5] The composition according to [4], wherein in formula (I), R is a methyl group, n is 0, m is 0, and Z is a t-butoxy group. [Effects of the Invention]

[0017] The present invention is expected to have the effect of reducing or preventing the effects of salt stress on plants. The present invention can improve plant growth health even in soil in coastal areas where seawater may flood or infiltrate, or in arid regions or in saline soil artificially created by inappropriate irrigation. The present invention can improve the quality and quantity of harvested crops even when subjected to salt stress. [Brief explanation of the drawings]

[0018] [Figure 1] This figure shows the amount of water lost after one day of filling the Wagner pots with water on the 68th day after sowing, comparing the amount of water lost after treatment with and without chemical solution. [Figure 2] FIG. 10 is a graph comparing the length of dead leaf tips 68 days after sowing between plants treated with and without chemical solution treatment. [Figure 3] FIG. 10 is a graph comparing the number of dead stems and the number of rolled leaves 68 days after sowing between plants with and without chemical treatment. [Figure 4] FIG. 10 is a graph comparing the number of crown roots and the number of aboveground roots 68 days after sowing between plants treated with and without chemical solution treatment. [Figure 5] This is a graph comparing plant height and number of stems 18 days after heading (92 days after sowing) between plants with and without chemical treatment. [Figure 6]FIG. 1 is a graph comparing the number of days from sowing to the beginning of heading with and without chemical treatment. [Figure 7] This figure compares the number of panicles 18 days (92 days after sowing) and 32 days (106 days after sowing) after the start of heading, with and without chemical treatment. In the figure, DAH indicates the number of days elapsed since the start of heading (74 days after sowing), and the numbers in parentheses indicate the date. [Figure 8] This figure compares flag leaf color 10 days (84 days after sowing), 18 days (92 days after sowing), and 32 days (106 days after sowing) after the start of heading, with and without chemical treatment. The numbers at the beginning of the bar graphs are SPAD values. In the figure, DAH indicates the number of days elapsed since the start of heading (74 days after sowing), and the numbers in parentheses indicate the date. [Figure 9] FIG. 1 is a graph comparing the number of panicles, panicle length, and culm length three weeks before harvest between plants with and without chemical treatment. [Figure 10] This is a graph comparing the white rice grain index, number of dead flag leaf individuals, and number of damaged flag leaf individuals three weeks before harvest with and without chemical treatment. The white rice grain index is an index per ear calculated using the following formula: White rice grain index = (A x 1) + (B x 0.5) + (C x 0) A: Total number of rice grains with a white area ratio of 100% (completely white rice grains) B: Total number of rice grains with a white area ratio of more than 0 but less than 100% (part of the rice grain is white) C: Total number of rice grains with a white area ratio of 0 (green rice grains) [Figure 11] This is a graph comparing the weight of polished brown rice and the weight of 1,000 kernels harvested with and without chemical treatment. [Figure 12] This is a graph showing the total number of grains harvested, comparing those with and without chemical treatment. [Figure 13] This is a graph comparing the ripening rate with and without chemical treatment. [Figure 14] FIG. 1 is a graph showing a comparison of the total % of total immature grains and the total % of white immature grains between those with and without chemical treatment. [Figure 15] FIG. 10 is a diagram showing temperatures during the implementation period of Test Example 4. DETAILED DESCRIPTION OF THE INVENTION

[0019] The method of the present invention for reducing or preventing the effects of salt stress on plants comprises applying at least one compound selected from the group consisting of a compound represented by formula (I) (hereinafter sometimes referred to as compound (I)) and a salt thereof (hereinafter sometimes referred to as a salt of compound (I)) to a plant that is exposed to salt stress or that may be exposed to salt stress.

[0020] [ka] [In formula (I), R represents a C1-6 alkyl group; X represents a halogeno group; n represents the number of Xs and is an integer of 0 to 2, and when n is 2 or greater, Xs may be the same or different; Y represents a halogeno group; m represents the number of Y's and is an integer of 0 to 3, and when m is 2 or more, Y's may be the same or different from each other; and Z represents a C1-8 alkyl group or a C1-8 alkoxy group.

[0021] In formula (I), Wavy line [ka] is an undefined single stereo bond (see Non-Patent Document 1).

[0022] The compound represented by formula (I) may be the (E) isomer alone, the (Z) isomer alone, or a mixture of the (E) and (Z) isomers. A mixture of the (E) and (Z) isomers can be separated and purified to obtain the (E) isomer alone or the (Z) isomer alone. The (Z) isomer of the compound represented by formula (I) is preferred because it is highly effective in reducing or preventing the effects of salt stress on plants. However, in natural environments, the (E) isomer may change from the (E) isomer to the (Z) isomer or from the (Z) isomer to the (E) isomer due to the action of light or other factors, and a mixture of the (E) and (Z) isomers tends to be stabilized at a certain ratio. The stabilization ratio between the (E) and (Z) isomers varies depending on the compound.

[0023] Examples of the C1-6 alkyl group for R in formula (I) include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, amyl, isoamyl, s-amyl, t-amyl, and hexyl. Of these, methyl is preferred. C1-6 indicates that the group contains 1 to 6 carbon atoms.

[0024] Examples of the halogeno group for X in formula (I) include a chloro group, a bromo group, an iodo group, and a fluoro group, of which a chloro group or a fluoro group is preferred. n represents the number of X and is an integer of 0 to 2. When n is 2 or more, X may be the same or different. n is preferably 0.

[0025] Examples of the halogeno group for Y in formula (I) include a chloro group, a bromo group, an iodo group, and a fluoro group. Of these, a chloro group or a fluoro group is preferred. m represents the number of Y's and is an integer of 0 to 3. When m is 2 or more, the Y's may be the same or different. m is preferably 0.

[0026] Examples of the C1-8 alkyl group for Z in formula (I) include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, amyl, isoamyl, s-amyl, t-amyl, hexyl, heptyl, and octyl groups. Of these, butyl is preferred. C1-8 indicates that the group contains 1 to 8 carbon atoms.

[0027] Examples of the C1-8 alkoxy group for Z in formula (I) include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, an s-butoxy group, a t-butoxy group, an n-amyloxy group, an isoamyloxy group, an s-amyloxy group, a t-amyloxy group, a hexyloxy group, a heptoxy group, an octyloxy group, etc. Among these, a butoxy group is preferred, and a t-butoxy group is particularly preferred.

[0028] Compound (I) in which R is a methyl group, n is 0, m is 0, and Z is a t-butoxy group (compound represented by formula (I)-1) is particularly preferred. [ka]

[0029] The salt of Compound (I) is not particularly limited as long as it is an agriculturally and horticulturally acceptable salt. Examples thereof include salts of inorganic acids such as hydrochloric acid and sulfuric acid; salts of organic acids such as acetic acid and lactic acid; salts of alkali metals such as lithium, sodium, and potassium; salts of alkaline earth metals such as calcium and magnesium; salts of transition metals such as iron and copper; salts of organic bases such as triethylamine, tributylamine, pyridine, and hydrazine; and ammonium salts.

[0030] Compound (I) or a salt of compound (I) is not particularly limited by its production method, and can be obtained using known chemical reactions. A salt of compound (I) can be obtained from compound (I) using known chemical reactions. Examples of methods for producing compound (I) or a salt of compound (I) of the present invention include the method described in Patent Document 3.

[0031] The compound (I) and / or a salt of compound (I) to be applied may be compound (I) and / or a salt of compound (I) as it is, or may be a composition containing compound (I) and / or a salt of compound (I) (a composition that reduces or prevents the effects of salt stress on plants).

[0032] A composition for reducing or preventing the effects of salt stress on plants (hereinafter sometimes referred to as the composition of the present invention) contains, as an active ingredient, at least one selected from the group consisting of compounds represented by formula (I) and salts thereof. The composition of the present invention may contain other ingredients in addition to compound (I) and / or a salt of compound (I). The content of compound (I) and / or a salt of compound (I) in the composition of the present invention varies depending on the formulation, application method, and other conditions, but is preferably 0.5 to 95% by mass, more preferably 2 to 70% by mass.

[0033] The composition of the present invention may contain other ingredients, such as conventional solid carriers, liquid carriers, dispersants, diluents, emulsifiers, spreaders, thickeners, adjuvants, etc. Examples of formulations include wettable powders, liquids, oils, dusts, granules, sols (flowables), etc.

[0034] Examples of solid or liquid carriers include talc, clay, bentonite, kaolin, diatomaceous earth, montmorillonite, mica, vermiculite, gypsum, calcium carbonate, white carbon, wood flour, starch, alumina, silicates, sugar polymers, waxes, water, alcohols (methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, ethylene glycol, benzyl alcohol, etc.), petroleum distillates (petroleum ether, kerosene, solvent naphtha, etc.), aliphatic or alicyclic hydrocarbons (n-hexane, cyclohexane, etc.), aromatic hydrocarbons (benzene, toluene, xylene, ethylbenzene, chlorobenzene, cumene, methyl naphtha, etc.), and the like. Examples of suitable solvents include toluene, methyl ether, ethylene oxide, tetrahydrofuran, ketones (acetone, methyl ethyl ketone, cyclohexanone, methyl isobutyl ketone, etc.), esters (ethyl acetate, butyl acetate, ethylene glycol acetate, amyl acetate, etc.), acid amides (dimethylformamide, dimethylacetanilide, etc.), nitriles (acetonitrile, propionitrile, acrylonitrile, etc.), sulfoxides (dimethyl sulfoxide, etc.), and alcohol ethers (ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, etc.).

[0035] Examples of adjuvants include nonionic surfactants (polyoxyethylene alkyl ethers, polyoxyethylene alkyl esters, polyoxyethylene alkylphenyl ethers, polyoxyethylene sorbitan alkyl esters, sorbitan alkyl esters, etc.), anionic surfactants (alkylbenzenesulfonates, alkyl sulfosuccinates, polyoxyethylene alkyl sulfates, arylsulfonates, etc.), cationic surfactants (alkylamines, polyoxyethylene alkylamines, quaternary ammonium salts, etc.), amphoteric surfactants (alkylaminoethylglycine, alkyldimethylbetaine, etc.), polyvinyl alcohol, hydroxypropyl cellulose, carboxymethyl cellulose, gum arabic, tragacanth gum, xanthan gum, polyvinyl acetate, gelatin, casein, and sodium alginate.

[0036] The composition of the present invention may contain other components such as known pesticides, known fertilizers, etc. Examples of pesticides include agricultural and horticultural fungicides, plant growth regulators, insecticides, and acaricides.

[0037] Sensitivity to salt stress varies among plant species, and even within the same species, it varies depending on the growth stage. Sensitivity is also affected by meteorological conditions such as temperature, humidity, and light intensity, as well as physicochemical environmental conditions such as the type of salt and soil moisture. The plants to which the present invention is applicable are not particularly limited, as long as they are exposed to salt stress or are at risk of being exposed to salt stress. Examples of plants to which the present invention is applicable include: cereals of the Gramineae family, such as rice, barley, wheat, barnyard millet, corn, and foxtail millet; vegetables, such as pumpkin, turnip, cabbage, radish, Chinese cabbage, spinach, bell pepper, and tomato; flowering plants, such as chrysanthemum, gerbera, pansy, orchid, peony, and tulip; beans, such as adzuki beans, kidney beans, soybeans, peanuts, broad beans, and peas; tubers, such as potato, sweet potato, taro, yam, and taro; and allium species, such as leeks, onions, and scallions.

[0038] Application to plants can be directly or indirectly applied to plants, and examples of application to plants include spraying, coating, etc. on planted plants (stems, leaves, etc.), spraying, irrigation, mixing, etc. on soil in which plants are planted, spraying, smearing, etc. on plant seeds (seeds, bulbs, etc.), and spraying or adding to the water medium in which plants are planted.

[0039] The application rate varies depending on the target plant, the growing environment, and other factors. For example, in the case of foliar application, it is preferable to apply 50 to 300 L of a solution containing an active ingredient at a concentration of preferably 1 to 10,000 ppm, more preferably 10 to 1,000 ppm, per 10 ares. In the case of soil application and surface application, it is preferable to apply 0.1 to 1,000 g, particularly preferably 10 to 100 g, of the active ingredient per 10 ares. In the case of seed treatment, it is preferable to apply 0.001 to 50 g of the active ingredient per 1 kg of seeds. Therefore, it is preferable to dilute the composition of the present invention with water to the desired ratio before application.

[0040] The effects of the present invention will now be specifically explained using test examples, although the scope of the present invention is not limited to these test examples.

[0041] (Test Example 1) Wheat seeds A flowable preparation containing 10% of the compound represented by formula (I)-1 was diluted with water to 10 3 double and ten 4 The solution was diluted 1:1 to obtain drug solution 1a and drug solution 1b. Eight layers of filter paper were placed in the center of a petri dish, and wheat seeds (Norin 61) (6 grains) were placed on top of the filter paper. Four such dishes were prepared. (1) 125 mM sodium chloride and 10 ml of the drug solution 1a were poured into a petri dish (Example 1a). (2) 125 mM sodium chloride and 10 ml of the drug solution 1b were poured into a petri dish (Example 1b). (3) 125 mM sodium chloride and 10 ml of water were poured into a petri dish (Comparative Example 1a). (4) 10 ml of water was poured into the petri dish (Comparative Example 1b). Each petri dish was placed in a growth chamber set at 25°C with a light / dark ratio of 16:8. After six days, the number of roots, root length, and stem / leaf length of six seeds from each of (1) to (4) were measured. The averages and recovery rates of each measurement are shown in Table 1. The recovery rate was calculated using the following formula. (XY) / (ZY) x 100 X: Chemical treatment with sodium chloride Y: Untreated with sodium chloride Z: Untreated, no sodium chloride

[0042] [Table 1]

[0043] Examples 1a and 1b, in which salt stress was applied using the compound represented by formula (I-1) of the present invention, showed better recovery than Comparative Example 1a, in which salt stress was applied without using the compound represented by formula (I-1).

[0044] (Test Example 2) Corn seeds A flowable preparation containing 10% of the compound represented by formula (I)-1 was diluted with water to 10 6 The solution was diluted 1:1 to obtain drug solution 2a. Eight layers of filter paper were placed in the center of a petri dish, and five kernels of corn (P2307) were placed on top of the filter paper. Four such dishes were prepared. (1) 125 mM sodium chloride and 10 ml of the drug solution 2a were poured into a petri dish (Example 2a). (2) 125 mM sodium chloride and 10 ml of water were poured into a petri dish (Comparative Example 2a). (3) 10 ml of water was poured into the petri dish (Comparative Example 2b). Each petri dish was placed in a growth chamber set at 25°C with a light / dark ratio of 16:8. After four days, the number of roots, root length, and stem / leaf length were measured for five seeds from each of (1) to (3). The average values ​​and recovery rates are shown in Table 2. The calculation of recovery rate was the same as in Test Example 1.

[0045] [Table 2]

[0046] Example 2a, in which salt stress was applied using the compound represented by formula (I-1) of the present invention, showed a better recovery than Comparative Example 2a, in which salt stress was applied without using the compound represented by formula (I-1).

[0047] (Test Example 3) Wheat seeds A flowable preparation containing 10% of the compound represented by formula (I)-1 was diluted with water to 10 5 double and ten 7 The solution was diluted 1:1 to obtain drug solution 3a and drug solution 3b. Eight layers of filter paper were placed in the center of a petri dish, and wheat seeds (Norin 61) (6 grains) were placed on top of the filter paper. Four such dishes were prepared. (1) 125 mM sodium chloride and 10 ml of the drug solution 2a were poured into a petri dish (Example 3a). (2) 125 mM sodium chloride and 10 ml of the drug solution 2b were poured into a petri dish (Example 3b). (3) 125 mM sodium chloride and 10 ml of water were poured into a petri dish (Comparative Example 3a). (4) 10 ml of water was poured into the petri dish (Comparative Example 3b). Each petri dish was placed in a growth chamber set at 25°C with a light / dark ratio of 16:8. After four days, the number of roots, root length, and stem / leaf length were measured for five seeds from each of (1) to (4). The average values ​​and recovery rates are shown in Table 3. The calculation of recovery rate was the same as in Test Example 1.

[0048] [Table 3]

[0049] In Examples 3a and 3b, in which salt stress was applied using the compound represented by formula (I-1) of the present invention, the roots showed greater recovery than in Comparative Example 3a, in which salt stress was applied without using the compound represented by formula (I-1).

[0050] (Test Example 4) Rice In mid-June, Arakida soil (2mm sieve under, Akagi Engei) was placed in a Wagner pot (1 / 5000a), and five dried rice seeds (Koshihikari: Oryza Sativa) were sown in the center of the pot at a depth of 3-5mm to begin direct sowing in flooded water. 28 days after sowing, all but one well-grown individual, which had reached 2-3 minutes of tillering, was thinned out with scissors. 10 pots were prepared.

[0051] The seeds were dried between 47th and 49th days after sowing. A flowable formulation containing 10% of the compound represented by formula (I)-1 was mixed with water for 10 minutes. 3 On the 50th day after sowing, 56 ml (0.28 gai / 2.8 L / m) of solution was added to 5 pots. 2 The plants were then treated with a solution of 1000 mg of the drug solution 4 (equivalent to 280 gai per 10 a) by dripping in water (drug solution treatment). Cultivation was continued together with the remaining 5 pots (untreated). A 10 g / L aqueous solution of sodium chloride a was prepared. On the 57th day after sowing, aqueous solution a was poured into two pots that had been flooded with water and dripped with chemical solution 4 and two pots that had not been flooded with water and dripped with chemical solution 4 (Example 4a and Comparative Example 4a). On the 58th, 59th, 65th, 66th, 72nd, 73rd, 79th, and 80th days after sowing, tap water was allowed to flow in. On the other days, the flow of solution a continued until the 84th day after sowing. From the 85th day after sowing onwards, tap water was allowed to flow in. Flowering began on the 81st day after sowing.

[0052] On the 68th day after sowing, the number of dead stems, the number of rolling leaves, the number of crown roots, the amount of water loss, and the length of dead leaf tips were measured (Figures 1 to 4). At or after the heading stage, plant height, number of stems, culm length, number of panicles, panicle length, number of white grains, flag leaf color, and number of withered and dead flag leafs were measured (Figures 5 to 8). On the 106th day after sowing, the culm length, number of panicles, panicle length, number of white grains, flag leaf color, and number of withered and dead flag leaves were measured (Figures 9 and 10). On the 126th day after sowing, the rice was harvested with scissors and dried in a greenhouse for about a week. The rice grains were then harvested using a tsubo-harvesting thresher, and the brown rice was obtained using a testing huller. The weight of the coarse and polished brown rice, the total number of grains, the percentage of immature grains, and the percentage of ripened grains (sorted using saline with a specific gravity of 1.06) were measured (Figures 11 to 14). The results are shown in Figures 1 to 15. When salt stress was applied using the compound represented by formula (I-1) of the present invention, Example 4a often showed better values ​​than Comparative Example 4a, in which salt stress was applied without using the compound represented by formula (I-1). In addition, a similar effect was observed in a test in which a 2g / L sodium chloride solution was drip-applied to produce 28gai per 10a.

[0053] (Test Example 5) Corn, soybeans (1) Example 5a An 8 g / L sodium chloride solution and the drug solution 5a were irrigated. (2) Comparative Example 5a Water containing 8 g / L of sodium chloride solution was irrigated. (3) Comparative Example 5b Water was irrigated. Polypots were filled with Kannami soil, and edible corn (Idaho Sweet 88) and soybean (Enrei) seeds were sown in the center of each pot (3 cm deep), with three seeds per pot. Three replicates were performed. The plants were grown in a greenhouse with submerged irrigation. A flowable preparation containing 5% of the compound represented by formula (I)-1 was diluted with water for 10 minutes. 3 The solution was diluted 1:1 to prepare Chemical Solution 5, and 17.3 ml of the solution was drenched per pot on the 8th day after sowing (Example 5a only). After the chemical treatment, pots without holes were placed on the bottom, and tap water was misted from above on weekends and holidays, and 50 ml of tap water per pot was drenched in the soil every day on weekdays. From the 11th day after sowing, 50 ml of an 8 g / L sodium chloride solution was drenched into the soil per pot every day (Example 5a and Comparative Example 5a only). On the 19th day after sowing, maximum root length (cm), plant height (cm), and dry weight (g) of above-ground and below-ground parts were measured. The results are shown in Table 4.

[0054] [Table 4]

[0055] Example 5a, in which salt stress was applied using the compound represented by formula (I-1) of the present invention, showed better values ​​for both corn and soybean than Comparative Example 5a, in which salt stress was applied without using the compound represented by formula (I-1).

[0056] (Test Example 6) Wheat (1) Example 6a An 8 g / L sodium chloride solution and the chemical solution 6a were irrigated. (2) Comparative Example 6a Water containing 8 g / L of sodium chloride solution was irrigated. (3) Comparative Example 6b Water was irrigated. Polypots were filled with Kannami soil, and five wheat seeds (variety: Kitahonami) were sown in the center of each pot (3 cm deep). Three replicates were performed. After sowing, the seeds were left in a growth chamber (20°C, dark room) for 4 days and then transferred to a greenhouse. A flowable preparation containing 5% of the compound represented by formula (I)-1 was diluted with water for 10 minutes. 3 The solution was diluted 1:1 to prepare Chemical Solution 6, and 17.3 ml of the solution was drenched per pot on the 7th day after sowing (Example 6a only). From the 10th day after sowing, 30 ml of 8 g / L sodium chloride was drenched into the soil per pot once a day (Example 6a and Comparative Example 6a only). On the 17th day after sowing, maximum root length (cm), number of roots (plants), plant height (cm), and dry weight (g) of above-ground and below-ground parts were measured. The results are shown in Table 5.

[0057] [Table 5]

[0058] Example 6a, in which salt stress was applied using the compound represented by formula (I-1) of the present invention, showed better values ​​for the number of roots, plant height, and underground dry weight than Comparative Example 6a, in which salt stress was applied without using the compound represented by formula (I-1).

[0059] As described above, it is clear that the present invention can reduce or prevent the effects of salt stress on plants.

Claims

1. A method for reducing or preventing the effects of salt stress on a plant, comprising applying at least one compound selected from the group consisting of the compound represented by formula (I) and a salt thereof to a plant that is exposed to salt stress or that may be exposed to salt stress. 【Chemistry 1】 [In formula (I), R represents a C1-6 alkyl group; X represents a halogeno group; n represents the number of Xs and is an integer of 0 to 2, and when n is 2 or more, Xs may be the same or different; Y represents a halogeno group; m represents the number of Y's and is an integer of 0 to 3, and when m is 2 or more, Y's may be the same or different; and Z represents a C1-8 alkyl group or a C1-8 alkoxy group.

2. 2. The method according to claim 1, wherein in formula (I), R is a methyl group, n is 0, m is 0, and Z is a t-butoxy group.

3. 3. The method according to claim 1 or 2, wherein application to plants is by spraying on planted plants, drenching the soil in which the plants are planted, smearing on plant seeds, or adding to the water medium in which the plants are planted.

4. A composition for reducing or preventing the effects of salt stress on plants, comprising as an active ingredient at least one selected from the group consisting of compounds represented by formula (I) and salts thereof. [In formula (I), R represents a C1-6 alkyl group; X represents a halogeno group; n represents the number of Xs and is an integer of 0 to 2, and when n is 2 or more, Xs may be the same or different; Y represents a halogeno group; m represents the number of Y's and is an integer of 0 to 3, and when m is 2 or more, Y's may be the same or different; and Z represents a C1-8 alkyl group or a C1-8 alkoxy group.

5. 5. The composition according to claim 4, wherein in formula (I), R is a methyl group, n is 0, m is 0, and Z is a t-butoxy group.

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