JP2022114322A - Plant growth inhibition suppressing or alleviating agent - Google Patents

Abstract

To provide an agent for suppressing or alleviating plant growth inhibition due to oxidative stress that can actually be used in a plant cultivation environment.SOLUTION: Provided is an agent for suppressing or alleviating plant growth inhibition due to oxidative stress that contains 5-amino-4-hydroxypentanoic acid, an ester thereof, or a salt thereof as an active ingredient.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to an agent for suppressing or alleviating plant growth inhibition due to oxidative stress.

Plant growth is stunted under various stress environments that exceed normal growing environmental conditions, such as strong light, dryness, high temperature, high salt concentration, and flooding (low oxygen). One of the main causes of these growth inhibitions is that the light energy that cannot be consumed by photosynthesis cannot be processed by the photosynthetic pigments and electron transfer system of plant chloroplasts, and reactive oxygen species are generated in the surroundings, resulting in oxidative stress. be. Plants have ascorbic acid/glutathione pathways, antioxidants such as polyphenols and carotenoids, and enzymes such as SOD as mechanisms for scavenging reactive oxygen. Causes damage and stunting of plants.

As a technique for avoiding growth inhibition due to such oxidative stress, ALDH-overexpressing plants with improved ability to scavenge active oxygen (for example, paraquat resistance) (Non-Patent Document 1) and plant roots that absorb an aqueous solution of high hydrogen concentration. A method for avoiding photo-oxidation damage to plants that have been exposed to the sun (Patent Document 1) and a method for administering formic acid and methanol to plants (Patent Document 2) have been proposed.

JP 2011-193851 A JP-A-2000-312531 JP-A-2002-284750 JP-A-2003-88393 WO2014/136863 JP 2019-151577 A

Plant, Cell and Environment (2006) 29, 1033-1048

However, the means described in Patent Document 1 requires a hydrogen gas generator and is not practical. Moreover, the formic acid and methanol used in Patent Document 2 are not practical in consideration of their safety to humans.
Accordingly, an object of the present invention is to provide an agent for suppressing or alleviating plant growth inhibition due to oxidative stress, which can be actually used in a plant cultivation environment.

Therefore, the present inventor cultivated plants under oxidative stress conditions such as strong light to cause growth inhibition, and applied various ingredients to examine the effect on the growth inhibition. The inventors have found that an acid, an ester thereof, or a salt thereof suppresses or alleviates the growth inhibition of plants caused by the oxidative stress, and completed the present invention.

That is, the present invention provides the following inventions [1] to [8].
[1] An agent for suppressing or alleviating plant growth inhibition due to oxidative stress, comprising 5-amino-4-hydroxypentanoic acid, an ester thereof, or a salt thereof as an active ingredient.
[2] The environment in which plant growth is inhibited by oxidative stress is an environment in which the ratio of ascorbic acid/dehydroascorbic acid in the plant is reduced to at least 4/5 or less compared to normal growth conditions without oxidative stress [1] ] suppressing or mitigating agents according to the above.
[3] The environment in which oxidative stress inhibits plant growth is an environment in which the ratio of glutathione/oxidized glutathione in the plant is reduced to at least 4/5 or less compared to normal growth conditions without oxidative stress [1] A suppressing or mitigating agent as described.
[4] Any one of [1] to [3], wherein the environment in which oxidative stress inhibits plant growth is selected from strong light, high temperature, high salt concentration, flooding, and dryness. Suppressor or alleviator of
[5] A method for suppressing or alleviating plant growth inhibition due to oxidative stress, which comprises applying 5-amino-4-hydroxypentanoic acid, an ester thereof, or a salt thereof.
[6] The environment in which plant growth is inhibited by oxidative stress is an environment in which the ratio of ascorbic acid/dehydroascorbic acid in the plant is reduced to at least 4/5 or less compared to normal growth conditions without oxidative stress [5] ] method of suppressing or mitigating described.
[7] The environment in which oxidative stress inhibits plant growth is an environment in which the ratio of glutathione/oxidized glutathione in the plant is reduced to at least 4/5 or less compared to normal growth conditions without oxidative stress [5] Method of suppression or mitigation as described.
[8] The method for suppressing or alleviating the effect of any one of [5] to [7], wherein the environment in which oxidative stress inhibits plant growth is selected from strong light, high temperature, and dry conditions.

According to the present invention, by applying 5-amino-4-hydroxypentanoic acid, its ester, or a salt thereof, plants can grow under oxidative stress environments such as strong light, high temperature, dryness, high salt concentration, and flooding. Inhibition is significantly reduced or alleviated. Therefore, application of 5-amino-4-hydroxypentanoic acid, its esters, or salts thereof provides sufficient growth and yield when plants are grown under an oxidative stress environment.

The ascorbic acid/glutathione pathway, which is one of the major active oxygen scavenging systems in plants, is shown. In the steady state, the reduced forms of glutathione and ascorbic acid are abundant, but when exposed to oxidative stress, the oxidized form increases, and the stress is relieved and eliminated by returning to the oxidized form. FIG. 3 shows growth inhibition by oxidative stress (intense light) and the concentration-dependent effect of 5-amino-4-hydroxypentanoic acid on it. s-HAVA: 5-amino-4-hydroxypentanoic acid, NL: normal light (70 μE), HL: high light (1000 μE) FIG. 2 is a diagram showing a decrease in glutathione/oxidized glutathione ratio (GSH/GSSG) due to oxidative stress (intense light), and the improvement effect of 5-amino-4-hydroxypentanoic acid (and the effect of reducing GSSG) thereon. HAVA: 5-amino-4-hydroxypentanoic acid, NL: normal light (70 μE), HL: high light (1000 μE) FIG. 2 is a diagram showing a decrease in the ascorbic acid/dehydroascorbic acid ratio (AsA/DHA) due to oxidative stress (intense light) and the improvement effect of 5-amino-4-hydroxypentanoic acid thereon (and the effect of reducing DHA). HAVA: 5-amino-4-hydroxypentanoic acid, NL: normal light (70 μE), HL: high light (1000 μE) FIG. 2 shows the activity-increasing effect of 5-amino-4-hydroxypentanoic acid on catalase (CAT) and ascorbate peroxidase (APX) in the ascorbic acid/glutathione pathway, which are major active oxygen scavenging systems in plants. HAVA: 5-amino-4-hydroxypentanoic acid, NL: normal light (70 μE), HL: high light (1000 μE) Graph showing the activity-increasing effect of 5-amino-4-hydroxypentanoic acid on monodehydroascorbate reductase (MDAR) and dehydroascorbate reductase (DHAR) in the ascorbic acid/glutathione pathway, which is the main active oxygen scavenging system in plants. is. HAVA: 5-amino-4-hydroxypentanoic acid, NL: normal light (70 μE), HL: high light (1000 μE)

The active ingredient of the agent for suppressing or alleviating plant growth inhibition due to oxidative stress of the present invention is 5-amino-4-hydroxypentanoic acid, esters thereof, or salts thereof.
5-Amino-4-hydroxypentanoic acid, its esters, or salts thereof are known as intermediates for the production of pharmaceuticals (Patent Documents 3 and 4), and also promote the growth of plants under normal cultivation conditions. (Patent Document 5) and suppressing plant pathogen infection (Patent Document 6).

Ester residues in 5-amino-4-hydroxypentanoic acid esters include hydrocarbon groups having 1 to 10 carbon atoms. Examples of hydrocarbon groups having 1 to 10 carbon atoms include saturated aliphatic hydrocarbon groups having 1 to 10 carbon atoms, unsaturated aliphatic hydrocarbon groups having 2 to 10 carbon atoms, and alicyclic hydrocarbon groups having 3 to 10 carbon atoms. They include a hydrogen group, an alicyclic-aliphatic hydrocarbon group having 4 to 10 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, an aromatic-aliphatic hydrocarbon group having 7 to 10 carbon atoms, and the like. Preferred hydrocarbon groups are saturated aliphatic hydrocarbon groups.

Examples of the above saturated aliphatic hydrocarbon groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, 2-methylbutyl, n-hexyl, isohexyl, 3-methylpentyl, ethylbutyl, n-heptyl, 2-methylhexyl, n-octyl, isooctyl, tert-octyl, 2-ethylhexyl, 3-methylheptyl, n-nonyl, isononyl, 1-methyl Octyl, ethylheptyl, n-decyl, 1-methylnonyl and the like, and preferred saturated aliphatic hydrocarbon groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, and straight- or branched-chain alkyl groups having 1 to 6 carbon atoms such as n-hexyl.

Suitable specific examples of the unsaturated aliphatic hydrocarbon group include vinyl, allyl, isopropenyl, 2-butenyl, 2-methylallyl, 1,1-dimethylallyl, 3-methyl-2-butenyl, 3-methyl -3-butenyl, 4-pentenyl, n-hexenyl, n-octenyl, n-nonenyl, n-decenyl and the like, and preferred unsaturated aliphatic hydrocarbon groups include vinyl, allyl, isopropenyl, 2-butenyl, C2-C6 straight or branched alkenyl groups such as 2-methylallyl, 1,1-dimethylallyl, 3-methyl-2-butenyl, 3-methyl-3-butenyl, 4-pentenyl, and n-hexenyl is mentioned.

Specific examples of suitable alicyclic hydrocarbon groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, 3-methylcyclohexyl, 4-methylcyclohexyl, 4-ethylcyclohexyl and 2-methylcyclohexyl. Octyl, cyclopropenyl, cyclobutenyl, cyclopentenyl, cyclohexenyl, cyclopentenyl, cyclooctenyl, 4-methylcyclohexenyl, 4-ethylcyclohexenyl and the like, and preferred alicyclic hydrocarbon groups are cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl. cycloalkyl or cycloalkenyl groups having 3 to 6 carbon atoms such as , cyclopropenyl, cyclobutenyl, cyclopentenyl, and cyclohexenyl.

Suitable specific examples of the alicyclic-aliphatic hydrocarbon groups include cyclopropylethyl, cyclobutylethyl, cyclopentylethyl, cyclohexylmethyl, cyclohexylethyl, cycloheptylmethyl, cyclooctylethyl, 3-methylcyclohexylpropyl, 4-methylcyclohexylethyl, 4-ethylcyclohexylethyl, cyclopropenylbutyl, cyclobutenylethyl, cyclopentenylethyl, cyclohexenylmethyl, cycloheptenylmethyl, cyclooctenylethyl, and 4-methylcyclohexenylpropyl, and the like. and preferred alicyclic-aliphatic hydrocarbon groups include cycloalkyl-alkyl groups having 4 to 6 carbon atoms such as cyclopropylethyl and cyclobutylethyl.

Suitable specific examples of the aromatic hydrocarbon group include aryl groups such as phenyl and naphthyl; 4-methylphenyl, 3,4-dimethylphenyl, 3,4,5-trimethylphenyl, 2-ethylphenyl, n Alkyl-substituted phenyl groups such as -butylphenyl and tert-butylphenyl, and the like, and a preferable aromatic hydrocarbon group is phenyl.

Specific examples of the aromatic-aliphatic hydrocarbon groups include groups having 7 to 7 carbon atoms such as benzyl, 1-phenylethyl, 2-phenylethyl, 2-phenylpropyl, 3-phenylpropyl and 4-phenylbutyl. Ten phenylalkyl groups are mentioned.

Salts of 5-amino-4-hydroxypentanoic acid or esters thereof include, for example, hydrochloride, hydrobromide, hydroiodide, phosphate, methyl phosphate, ethyl phosphate, phosphite, hypoxite Phosphate, Nitrate, Sulfate, Acetate, Propionate, Toluenesulfonate, Succinate, Oxalate, Lactate, Tartrate, Glycolate, Methanesulfonate, Butyrate, Valerate , citrate, fumarate, maleate, malate and other acid addition salts, sodium salts, potassium salts, calcium salts and other metal salts, ammonium salts, alkylammonium salts and the like. These salts are used as an aqueous solution or powder at the time of use.

The above-mentioned 5-amino-4-hydroxypentanoic acid, esters thereof, or salts thereof may form hydrates or solvates, and any of them may be used alone or in combination of two or more. be able to. Moreover, an optically active form may be used, and a racemic form may be used.

5-Amino-4-hydroxypentanoic acid, esters thereof, or salts thereof can be produced by any of chemical synthesis, microbial production, and enzymatic production, and are described, for example, in Patent Documents 3 and 4. It can be manufactured according to the method of. Chemical reaction solutions and fermentation liquids before purification of 5-amino-4-hydroxypentanoic acid, its esters, or salts thereof produced in this way are used as they are without separation and purification unless they contain harmful substances. be able to. Moreover, a commercial item etc. can be used.

As described above, the present inventors have found that 5-amino-4-hydroxypentanoic acid, its esters, or salts thereof suppress or relieve the growth inhibition of plants caused by oxidative stress.
When plants are subjected to oxidative stress, the light energy that cannot be consumed in photosynthesis cannot be processed by the photosynthetic pigments and electron transport system in plant chloroplasts, and reactive oxygen species are generated in the surroundings. Plants have the ascorbic acid/glutathione pathway (see Fig. 1), antioxidants such as polyphenols and carotenoids, and enzymes such as SOD as mechanisms for scavenging reactive oxygen. It damages biological components such as lipids and causes growth inhibition of plants. 5-amino-4-hydroxypentanoic acid, its esters, or salts thereof remarkably suppress or alleviate such oxidative stress-induced plant growth inhibition.

The suppressor or ameliorator of the present invention contains 5-amino-4-hydroxypentanoic acid, its ester, or a salt thereof as a component, and when applied to a plant cultivated in an environment under oxidative stress, oxidative stress is alleviated.・By resolving the problem, it is possible to show an effect of suppressing or alleviating plant growth inhibition.
Here, the environment in which plant growth is inhibited by oxidative stress is an environment in which the ratio of ascorbic acid/dehydroascorbic acid in the plant is reduced to at least 4/5 or less compared to normal growing conditions without oxidative stress, or oxidative stress. It is an environment in which the ratio of glutathione/oxidized glutathione in the plant is reduced to at least 4/5 or less compared to the normal growth condition without culturing. This is because, in such an environment, the ascorbic acid/glutathione pathway cannot eliminate active oxygen due to oxidative stress.
One aspect of the environment in which oxidative stress causes plant growth inhibition in the present invention is an environment in which the ascorbic acid/dehydroascorbic acid ratio in the plant is reduced to at least 4/5 or less compared to normal growing conditions without oxidative stress. However, it is preferable to apply the inhibitor or alleviator of the present invention in an environment where the ratio of ascorbic acid/dehydroascorbic acid in the plant is reduced to at least 3/4 or less compared to normal growth conditions without oxidative stress. More preferably, the control or mitigating agents of the present invention are applied in environments where the ascorbic acid/dehydroascorbic acid ratio has been reduced to at least 2/3 or less, and the ascorbic acid/dehydroascorbic acid ratio has been reduced to at least 2/5 or less. It is more preferred to apply the control or mitigation agent of the present invention in a reduced environment.
One aspect of the environment in which oxidative stress inhibits plant growth in the present invention is an environment in which the ratio of glutathione/oxidized glutathione in the plant is reduced to at least 4/5 or less compared to normal growth conditions without oxidative stress. However, it is preferable to apply the suppressor or ameliorator of the present invention in an environment in which the glutathione/oxidized glutathione ratio in the plant is reduced to at least 3/4 or less compared to normal growth conditions without oxidative stress, and the glutathione More preferably, the suppressor or alleviator of the present invention is applied in an environment in which the glutathione/oxidized glutathione ratio has been reduced to at least 2/3 or less, and in an environment in which the glutathione/oxidized glutathione ratio has been reduced to at least 2/5 or less. , it is particularly preferred to apply the inhibitors or mitigants according to the invention.

Also, an environment in which the ascorbic acid/dehydroascorbic acid ratio in the plant is reduced to at least 4/5 or less compared to normal growth conditions without oxidative stress, or glutathione in plants compared to normal growth conditions without oxidative stress. /oxidized glutathione ratio is reduced to at least 4/5 or less, the plant cultivation environment is preferably an environment selected from strong light, high temperature, dryness, high salt concentration and under flooding. more preferred.
The ascorbic acid / dehydroascorbic acid ratio and the glutathione / oxidized glutathione ratio in plants in the oxidative stress and antioxidant system of such plants are described in, for example, Plant, Cell and Environment (2016) 39, 1140-1160. can be determined based on

5-Amino-4-hydroxypentanoic acid, its esters, or salts thereof remarkably suppress or alleviate plant growth inhibition due to oxidative stress. Inhibition of plant growth due to oxidative stress results in suppression of plant height growth, tillering suppression, and weight loss of aboveground parts and roots. When applied to plants, these growth inhibitions are suppressed or alleviated.
In addition, when the plant is subjected to oxidative stress as described above, the ascorbic acid/dehydroascorbic acid ratio in the plant is reduced to at least 4/5 or less compared to normal growth conditions without oxidative stress, or oxidative stress The glutathione/oxidized glutathione ratio in the plant is reduced to at least 3/4 or less compared to normal growth conditions without 5-amino-4-hydroxypentanoic acid and its When an ester or a salt thereof is applied, the active oxygen scavenging system of the ascorbic acid/glutathione pathway acts, the ascorbic acid/dehydroascorbic acid ratio and the glutathione/oxidized glutathione ratio are improved, catalase (CAT), ascorbic Acid peroxidase (APX), monodehydroascorbate reductase (MDAR) and dehydroascorbate reductase (DHAR) activities are also increased (see Figure 1).

Plants to which the suppressing or alleviating agent of the present invention is applied include, but are not limited to, grains and vegetables. Specific examples of grains include rice, wheat, barley, corn, buckwheat, and soybean. , adzuki beans, peas, edamame beans, beans, etc. Leafy vegetables such as tomatoes, eggplants, green peppers, paprika, cucumbers, shishito peppers, okra, strawberries, melons, watermelons, pumpkins, gourds, cabbage, Brussels sprouts, Chinese cabbage, Japanese mustard spinach, spinach, Asparagus, mizuna, lettuce, parsley, leek, etc. Stem flower vegetables include asparagus, leek, onion, garlic, spring onion, broccoli, cauliflower, edible chrysanthemum, Japanese ginger, etc. Root vegetables and potatoes include radish, turnip, radish, Examples include carrots, lotus roots, burdock roots, shallots, sweet potatoes, potatoes, and taro.

In the present invention, the suppressor or ameliorator may contain 5-amino-4-hydroxypentanoic acid, its ester, or a salt thereof. Compounds, acids, alcohols, vitamins, trace elements, metal salts, chelating agents, preservatives, antifungal agents, spreading agents and the like can be blended.

Plant growth regulators used here include, for example, brassinolides such as epibrassinolide, choline agents such as choline chloride and choline nitrate, indolebutyric acid, indoleacetic acid, ethiclozate agents, 1-naphthylacetamide agents, and isoprothiolane. drug, nicotinamide drug, hydroxyisoxazole drug, calcium peroxide drug, benzylaminopurine drug, metasulfocamb drug, oxyethylene docosanol drug, ethephon drug, cloquinhonac drug, gibberellin, streptomycin drug, daminozite drug, benzylamino Purine agents, 4-CPA agents, ancidol agents, inapenfide agents, uniconazole agents, chlormequat agents, Dikeblack agents, mefluidide agents, calcium carbonate agents, piperonyl butoxide agents and the like can be mentioned.

Sugars include, for example, glucose, sucrose, xylitol, sorbitol, galactose, xylose, mannose, arabinose, majulose, sucrose, ribose, rhamnose, fructose, maltose, lactose and maltotriose.

Examples of nitrogen-containing compounds include amino acids (asparagine, glutamine, histidine, tyrosine, glycine, arginine, alanine, tryptophan, methionine, valine, proline, leucine, lysine, glutamic acid, aspartic acid, isoleucine, etc.), urea, and ammonia. be done.

Examples of acids include organic acids (formic acid, acetic acid, propionic acid, butyric acid, valeric acid, oxalic acid, phthalic acid, benzoic acid, lactic acid, citric acid, tartaric acid, malonic acid, malic acid, succinic acid, glycolic acid, maleic acid, , caproic acid, caprylic acid, myristic acid, stearic acid, palmitic acid, pyruvic acid, α-ketoglutaric acid, levulinic acid, etc.), sulfurous acid, sulfuric acid, nitric acid, phosphorous acid, phosphoric acid, polyphosphoric acid and the like.

Examples of alcohols include methanol, ethanol, propanol, butanol, pentanol, hexanol, glycerol and the like.

Examples of vitamins include nicotinamide, vitamin B6, vitamin _B12 , vitamin _B5 , vitamin _C , vitamin _B13 , vitamin B1, vitamin _B3 , vitamin B2, vitamin K3 _, vitamin _{A ,} vitamin D. ₂ , vitamin D3 _, vitamin K1, α _- tocopherol, β-tocopherol, γ-tocopherol, σ-tocopherol, p-hydroxybenzoic acid, biotin, folic acid, nicotinic acid, pantothenic acid, α-liponic acid, etc. can be done.

Trace elements include, for example, boron, manganese, zinc, copper, iron, molybdenum, chlorine, and the like.

Examples of metal salts include calcium salts, potassium salts, magnesium salts, phosphates and the like.

Chelating agents include, for example, aminocarboxylic acid-based chelating agents (ethylenediaminetetraacetic acid, nitrilotriacetic acid, hydroxyethyliminodiacetic acid, hydroxyethylethylenediaminetriacetic acid, diethylenetriaminepentaacetic acid, triethylenetetraaminehexaacetic acid, dicarboxymethylglutamic acid, dihydroxy ethylglycine, 1,3-propanediaminetetraacetic acid, 1,3-diamino-2-hydroxypropanetetraacetic acid, etc.) and phosphonic acid-based chelating agents (hydroxyethylidenediphosphonic acid, methylenephosphonic acid, phosphonobutanetricarboxylic acid, etc.) etc. These chelating agents may be used as metal salts.

The inhibitor or alleviation agent of the present invention may be applied by any of foliar application, soil application or irrigation, and hydroponic irrigation. In addition, the absorption treatment may be carried out before planting the plant permanently or before taking cuttings.

When this agent is applied by foliage spraying treatment, the 5-amino-4-hydroxypentanoic acid, its ester or salt thereof is contained at a concentration of 0.0001 to 100 ppm, especially 0.005 to 1 ppm, It is preferable to use 10 to 1000 L, particularly 50 to 300 L of this per 10 ares. A spreading agent can be used for plants such as monocotyledonous plants to which the agent does not easily adhere to the leaf surface, but the type and amount used are not particularly limited.

When applying this agent by soil spraying or irrigation treatment or hydroponic irrigation treatment, 5-amino-4-hydroxypentanoic acid, its ester or salt thereof at a concentration of 0.0001 to 100 ppm, especially 0.01 to 1 ppm It is preferable to use 10 to 1000 L, particularly 50 to 300 L, of this per 10 ares in field cultivation, and 10 mL to 2 L, particularly 10 mL to 1 L of this per plant in potted cultivation.

When using this agent for absorption treatment before planting or before taking cuttings, 5-amino-4-hydroxypentanoic acid, its esters or their salts can be soaked and absorbed. The concentration of -4-hydroxypentanoic acid, its esters or salts thereof is desirably 0.0001 to 100 ppm, more preferably 0.00001 to 10 ppm, particularly 0.001 to 0.1 ppm. The immersion time is preferably 1 second to 1 week, especially 1 minute to 1 day.

A sufficient effect can be obtained with one treatment, but the effect can be further enhanced by performing the treatment multiple times. In this case, the above methods can be combined.

The present invention will now be described in detail with reference to examples, but these are given for illustrative purposes only and the present invention is not limited to these examples.

Example 1
Arabidopsis thaliana was sown and cultivated in Jiffy-7 (a soilless system for gardeners, manufactured by Jiffy Products International BV). The number of individuals was 1 individual/Jiffy-7, 8 pots/section. The basal fertilizer is the amount originally added to Jiffy-7, and top dressing is not applied. The temperature was 23° C. and the light intensity was 70 μE (normal light).
After sowing, vernalization treatment was performed for 2 days in a refrigerator. After 4 weeks of cultivation, 5-amino-4-hydroxypentanoic acid was administered to a final concentration of 1 μM, 3 μM or 5 μM. The plot was continuously cultivated under the condition of 1000 μE (strong light). After 2 weeks, the plants were harvested and weighed wet, dried at 50°C for 1 day and weighed dry.
As a result, as shown in FIG. 2, growth inhibition occurred when cultivated under strong light (1000 μE) compared to when cultivated under normal light (70 μE). On the other hand, when 5-amino-4-hydroxypentanoic acid is applied, the growth inhibition is remarkably suppressed, and 5-amino-4-hydroxypentanoic acid remarkably suppresses the growth inhibition due to oxidative stress under strong light. It turns out that

Example 2
Arabidopsis thaliana seeds were sterilized, sown in petri dishes containing Murashige-Skoog medium, and cultivated. The number of seeds was 64 grains/dish. The temperature was 23° C. and the light intensity was 70 μE (normal light).
After sowing, vernalization treatment was performed in a refrigerator for 2 days, and 10 days after cultivation, 5-amino-4-hydroxypentanoic acid was administered at a final concentration of 5 μM. ) was grown under After 3 days, Arabidopsis thaliana was harvested, and glutathione, oxidized glutathione, ascorbic acid, and dehydroascorbic acid in the plant body were measured.
The results are shown in FIGS. 3 and 4. FIG. FIG. 3 shows the glutathione/oxidized glutathione ratio, and FIG. 4 shows the ascorbic acid/dehydroascorbic acid ratio.
From FIG. 3, it can be seen that the glutathione/oxidized glutathione ratio decreased to about 2/3 by cultivation under strong light (1000 μE) compared to cultivation under normal light (70 μE), indicating that oxidative stress is applied. Application of 5-amino-4-hydroxypentanoic acid remarkably restored the reduction in the ratio of glutathione/oxidized glutathione due to cultivation under strong light (1000 μE), and eliminated oxidative stress.
From FIG. 4, it can be seen that the ascorbic acid/dehydroascorbic acid ratio is reduced to about 2/3 by cultivation under strong light (1000 μE) compared to cultivation under normal light (70 μE), indicating that oxidative stress is applied. . The application of 5-amino-4-hydroxypentanoic acid remarkably restored the decrease in the ascorbic acid/dehydroascorbic acid ratio due to cultivation under this strong light (1000 μE) and eliminated the oxidative stress.

Example 3
Arabidopsis thaliana was cultivated according to the same protocol as in Example 2. Three days later, Arabidopsis thaliana was harvested, and catalase (CAT), ascorbate peroxidase (APX), monodehydroascorbate reductase (MDAR), and dehydroascorbate reductase (DHAR) in the plant body were measured. The enzymatic activity was measured using the reagents and methods described in Plant, Cell and Environment (2016) 39, 1140-1160 of Non-Patent Document 1 (review) and references cited in the article.
The results are shown in FIGS. 5 and 6. FIG.
From FIGS. 5 and 6, by applying 5-amino-4-hydroxypentanoic acid, catalase (CAT), ascorbate peroxidase (APX), and monodehydroascorbine of the ascorbic acid/glutathione pathway, which are active oxygen scavenging systems in plants Both acid reductase (MDAR) and dehydroascorbate reductase (DHAR) activities were found to be increased.

Claims (8)

An agent for suppressing or alleviating plant growth inhibition due to oxidative stress, comprising 5-amino-4-hydroxypentanoic acid, an ester thereof, or a salt thereof as an active ingredient. 2. The environment according to claim 1, wherein the environment in which oxidative stress inhibits plant growth is an environment in which the ratio of ascorbic acid/dehydroascorbic acid in the plant is reduced to at least 4/5 or less compared to normal growing conditions without oxidative stress. Suppressing or alleviating agent. The suppression according to claim 1, wherein the environment in which oxidative stress inhibits plant growth is an environment in which the ratio of glutathione/oxidized glutathione in the plant is reduced to at least 4/5 or less compared to normal growth conditions without oxidative stress. or emollients. 4. The inhibitor or alleviation agent according to any one of claims 1 to 3, wherein the environment in which oxidative stress inhibits plant growth is an environment selected from strong light, high temperature and dry conditions. A method for suppressing or alleviating plant growth inhibition due to oxidative stress, which comprises applying 5-amino-4-hydroxypentanoic acid, its ester, or a salt thereof. 6. The environment according to claim 5, wherein the environment in which oxidative stress inhibits plant growth is an environment in which the ratio of ascorbic acid/dehydroascorbic acid in the plant is reduced to at least 4/5 or less compared to normal growing conditions without oxidative stress. suppression or mitigation methods; 6. Suppression according to claim 5, wherein the environment in which oxidative stress inhibits plant growth is an environment in which the glutathione/oxidized glutathione ratio in the plant is reduced to at least 4/5 or less compared to normal growth conditions without oxidative stress. or mitigation methods. 8. The method for suppressing or alleviating oxidative stress according to any one of claims 5 to 7, wherein the environment in which oxidative stress inhibits plant growth is an environment selected from strong light, high temperature and dry conditions.

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