JPH09255509A - Promoter for formation of chlorophyll and plant senescence preventing agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a chemical having efficiently promoting actions on the formation of chlorophyll even under weak light or a treating agent for indoor cultivated plants containing the chemical and further a plant senescence preventing agent capable of preventing the plants from defoliating, flowers from shedding and fruits from dropping, etc. SOLUTION: This promoter for the formation of chlorophyll comprises a lepidimoide represented by the formula (R is hydrogen atom, an alkyl group or an alkali metallic element) or its analog or a salt thereof as an active ingredient. The prepared promoter for the formation of the chlorophyll is used as a treating agent for indoor cultivated plants. Furthermore, the plant senescence preventing agent is prepared by using the lepidimoide represented by the formula or its analog or salt thereof as an active ingredient.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel chlorophyll formation promoter or plant antiaging agent.
More specifically, the present invention relates to a chlorophyll formation promoter or a plant anti-aging agent containing, as an active ingredient, a plant growth promoting substance, lepidimoid, an analog thereof, or a salt thereof.

[0002]

2. Description of the Related Art In recent years, indoor cultivation such as greenhouse cultivation and plant factory has become popular as a method for cultivating agricultural products. However, such indoor cultivation has a weak light intensity as compared with the usual outdoors, and the amount of light is small. There is a drawback that the leaf color of leafy vegetables and the like deteriorates due to lack. Therefore, in order to prevent such a decrease in leaf color of crops due to insufficient light quantity, it is usual to use artificial lighting in many indoor cultivations, and in plant factories in particular, cultivation is carried out under complete artificial lighting.

Since cultivation using such artificial lighting requires a lot of cost, as a method for reducing the production cost without degrading the quality of crops, a cultivation method in which the quality does not change even if the light quantity of artificial lighting is reduced. The development of chlorophyll (chlorophyll) in plants has been attempted to be developed as one of them. If the synthesis of chlorophyll is promoted, vegetables with a dark leaf color can be produced even under weak light, and the light amount of artificial lighting can be reduced without lowering the quality of the crops to reduce the production cost. In addition, darkening the leaf color of plants also improves the commercial value of crops.

Further, in order to reduce the production cost, attempts have been made to develop a method for preventing plant aging such as defoliation in order to efficiently cultivate the crop by reducing the production cost loss of the crop in a plant factory or the like.

As a method for accelerating the synthesis of chlorophyll, it has been attempted to use a chlorophyll formation (production) accelerator regardless of whether it is natural or synthetic. However, there is a problem that the effect is small under the low light such as indoor cultivation, though the effect is exhibited in the light intensity under the low temperature. Therefore, it is desired to develop a chlorophyll formation promoter that can efficiently promote the synthesis of chlorophyll even under weak light.

On the other hand, with respect to lepidimoid, which is a compound represented by the following general formula (I), or an analogue thereof or a salt thereof, a chemical synthesis method thereof as a plant growth promoter,
A method for extracting from a natural product and its physical properties have been reported (JP-A-6-49089 and JP-A-6-92819).
Japanese Patent Laid-Open Publication No. JP-A-2003-242242 is not known for its effect on chlorophyll synthesis promotion, and therefore, it has not been known to be used for crop production under low light to increase the leaf color of crops. It also prevents aging of plants and leaves
The effect of preventing flower drop and fruit drop was also unknown.

[0007]

Embedded image

[In the formula (I), R ¹ , R ² , R ³ , R ⁴ and R ⁵ each independently represent a hydrogen atom, an acetyl group or a benzyl group, and R ⁶ is a hydrogen atom, a hydroxyl group, Represents an acetoxy group or a benzyloxy group, R ⁷ represents a hydrogen atom, R ⁶ and R ⁷ may jointly represent another direct bond, and R ⁸ represents a carboxyl group, an alkyloxycarbonyl group, a hydroxy group. It represents a methyl group or an acetoxymethyl group. ]

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a drug having an action of efficiently promoting chlorophyll formation even under weak light or a treating agent for indoor cultivation plants containing the drug. Another object of the present invention is to provide a plant anti-aging agent which prevents leaves, flowers, fruits and the like of plants.

[0010]

[Means for Solving the Problems] As a result of diligent studies, the present inventors have found that lepizimoid or its analogs or salts thereof, which are known as plant growth promoting substances, act to promote the formation of chlorophyll (chlorophyll). Further, they have found that they have a function of preventing plant aging, and completed the present invention.

[0011] That is, the present invention relates to a chlorophyll formation promoter containing as an active ingredient a lepidimoid represented by the following general formula (I) or an analogue thereof or a salt thereof.

[0012]

[Chemical 6]

[In the formula (I), R ¹ , R ² , R ³ , R ⁴ and R ⁵ each independently represent a hydrogen atom, an acetyl group or a benzyl group, and R ⁶ is a hydrogen atom, a hydroxyl group, Represents an acetoxy group or a benzyloxy group, R ⁷ represents a hydrogen atom, R ⁶ and R ⁷ may jointly represent another direct bond, and R ⁸ represents a carboxyl group, an alkyloxycarbonyl group, a hydroxy group. It represents a methyl group or an acetoxymethyl group. ]

The present invention also relates to a treatment agent for indoor cultivated plants, which contains the chlorophyll formation promoter. Furthermore,
The present invention relates to a plant anti-aging agent containing a repidimoid represented by the above general formula (I) or an analog thereof or a salt thereof as an active ingredient.

By using the chlorophyll formation promoter of the present invention, it is possible to enhance the photosynthetic ability of plants, to produce leafy vegetables having a dark leaf color even in low light, and to prevent the leaf color from becoming light even in the dark. Therefore, it is possible to realize a cultivation method in which the quality is not changed even if the light amount of artificial lighting is reduced. Therefore, auxiliary lighting in greenhouse cultivation is unnecessary,
In addition, it is possible to reduce the production cost without degrading the quality of crops, as it is possible to reduce the illumination intensity in the plant factory. In addition, it is possible to improve the commercial value of crops by enabling the production of vegetables with dark leaf color. Therefore, it is particularly suitable as a treatment agent for indoor cultivation plants such as greenhouse cultivation and plant factories.

Further, by using the plant antiaging agent of the present invention, it is possible to prevent plant aging and prevent leaf fall, flower fall, physiological fruit drop, and the like, so that the production efficiency of crops can be improved. In particular, it is possible to further greatly reduce the cost loss in a plant factory or the like, which tends to be expensive.

[0017]

Embodiments of the present invention will be described below.

(1) Chlorophyll formation promoter of the present invention The chlorophyll formation promoter of the present invention has the general formula (I) above.
Is characterized in that a repidimoid represented by the formula (1) or an analog thereof or a salt thereof (hereinafter, may be simply referred to as "repidimoid") is used as an active ingredient.

In the general formula (I), R ¹ , R ² , R ³ ,
R ⁴ and R ⁵ each independently represent a hydrogen atom, an acetyl group or a benzyl group, R ⁶ represents a hydrogen atom, a hydroxyl group, an acetoxy group or a benzyloxy group, R ⁷ represents a hydrogen atom, and R ⁶ and R ⁷ may together represent another direct bond, and R ⁸ represents a carboxyl group, an alkyloxycarbonyl group, a hydroxymethyl group or an acetoxymethyl group. The alkyloxycarbonyl group for R ⁸ is preferably a methoxycarbonyl group.

Preferred examples of such lepidimoid or its analogs include the compounds shown below.

(1) In the above formula (I), R¹, R^Two,
R^Three, R^Four, And R^FiveIs a hydrogen atom, and R ⁶Is a hydroxyl group
R⁷Is a hydrogen atom, and R⁸Is a carboxyl group
Compound. (2) In the above formula (I), R¹, R^Two, R^Three, R^Four,as well as
R^FiveIs a hydrogen atom, and R ⁶Is a hydroxyl group, and R⁷Is hydrogen
An atom, R⁸A compound in which is a methoxycarboxyl group
Stuff. (3) In the above formula (I), R¹, R^Two, R^Three, R^Four,as well as
R^FiveIs a hydrogen atom, and R ⁶Is a hydroxyl group, and R⁷Is hydrogen
An atom, R⁸Is a hydroxymethyl group. (4) In the above formula (I), R¹, R^Two, R^Three, R^Four,as well as
R^FiveIs a hydrogen atom, and R ⁶Is a hydrogen atom, and R⁷But water
An elementary atom, R⁸A compound in which is a carboxyl group. (5) In the above formula (I), R¹, R^Two, R^Three, R^Four,as well as
R^FiveIs a benzyl group, R⁶Is a benzyloxy group
R⁷Is a hydrogen atom, and R⁸Is an acetoxymethyl group
Is a compound. (6) In the formula (I), R¹, R^Two, R^Three, R^Four,as well as
R^FiveIs an acetyl group, R⁶And R⁷One more in collaboration
Form two direct bonds, R⁸Is a methoxycarbonyl group
Is a compound. (7) In the formula (I), R¹, R^Two, R^Three, R^Four,as well as
R^FiveIs a hydrogen atom, and R ⁶And R⁷Another in collaboration
Form a direct bond of R⁸Is a compound in which is a carboxyl group
Stuff.

Examples of the salt of the repidimoid represented by the above general formula (I) or its analog include alkali metal salts such as sodium salt and potassium salt of the above-mentioned compounds.

Particularly preferred as the repidimoid of the present invention or its analog or a salt thereof is a compound having a chemical structure represented by the following general formula (II).

[0024]

Embedded image

[In the formula (II), R represents a hydrogen atom, an alkyl group or an alkali metal element. ]

In the general formula (II), examples of the alkyl group represented by R include a methyl group and an ethyl group. In addition, examples of the alkali metal element include sodium (Na) and potassium (K). In the present invention, in the above formula (II), the case where R is Na (sodium salt of lepidimoid) or the case where R is a hydrogen atom (sometimes referred to as carboxylic acid type lepidimoid) is particularly preferably used.

[0027] Lepidimoid is known as a physiologically active substance having a plant growth promoting effect, but its action for promoting the formation of chlorophyll was not known.
The mechanism of chlorophyll formation promoting action of lepidimoid is not necessarily clear, but it is considered that it may have an effect of promoting the synthesis of aminolevulinic acid which is a precursor of chlorophyll.

The repidimoid represented by the above general formula (I), its analogs or salts thereof can be obtained by a method such as extraction from a natural product, chemical synthesis and the like. As a method for extracting from a natural product, according to the method described in JP-A-6-49089, JP-A-6-92816, etc., it is obtained by extracting from plant seeds with water, isolating and purifying the seeds. You can That is, the seeds of the plant are immersed in water, and the seeds are cultivated and germinated in the immersion of the water as the case may be to extract the lepizimoid in the immersion liquid. When seeds are germinated, the culturing form is not particularly limited as long as it can germinate plant seeds, but usually a technique of germination under dark / aerated conditions is adopted. Further, the immersion temperature is usually 15 to 30 ° C., preferably 2 regardless of whether the seed is germinated or not.
It is 0 to 25 ° C. The immersion time is usually about 1 to 2 days. The immersion liquid is not particularly limited as long as it is ordinary water, but it is preferable to use distilled water in consideration of the efficiency of isolation and purification of lepidimoid. Next, after concentrating the immersion liquid in which the lepidimoid has been extracted in this manner by a conventional method, this is optionally filtered through gel filtration chromatography, high performance liquid chromatography, or the like, or a combination thereof to isolate the desired lepidimoid. -Can be purified.

Examples of plant seeds that can be used to extract lepidimoid include cress, sunflower, spinach, corn, okra, carrot, avena, parsley, barnyard grass, capsicum, buckwheat, tomato, cabbage,
Examples include seeds of plants selected from lettuce, citrus, burdock, honeywort, pea, Japanese radish, Scutellaria baicalensis and the like.

The chemical synthesis method of the repidimoid represented by the above general formula (I) or its analog or a salt thereof includes Kosemura, S., Yamamura, S., Kakuta, H., Mizuta.
ni, J., and Hasegawa, K., "Synthesis and absolute c
onfiguration of lepidimoide, a high potent allelop
athic substance from mucilage of germinated cress
seeds. "Tetrahedron Letters, 34 (16), 1993, p2653-26
56, or by reacting an α-L-rhamnose derivative with a D-glucose derivative according to the method described in JP-A-6-49089. This reaction is shown in the following reaction formula (Formula 8).

For example, after reacting α-L-rhamnose with benzyl alcohol to form benzyl glycoside,
A compound obtained by reacting with 2,2-dimethoxypropane to form isopropylidene, further reacting with benzyl bromide, and then deisopropyliding, is treated with dibutyltin oxide and benzyl bromide to give a compound represented by the following reaction formula ( a) is obtained. Then, the compound (c) can be obtained by reacting the compound (a) with the compound (b). The compound (b) used here is a known compound and can be synthesized from D-glucose in 7 steps (Acta Chem. Scand., 43, 471 (1989); Carboh.
See ydr. Res., 202, 225 (1990). Next, the desired compound can be obtained by treating the obtained compound (c) in combination with known reduction reaction, oxidation reaction and the like.

[0032]

Embedded image

[In the reaction formula, Bn represents a benzyl group, Ph represents a phenyl group, and OAc represents an acetyl group. ]

The lepidimoid thus obtained has the action of promoting the formation of chlorophyll. Therefore, the chlorophyll formation promoter of the present invention containing this as an active ingredient can activate chlorophyll synthesis in plants and produce crops with dark leaf color when used in various cultivation methods.

The dosage form of the chlorophyll formation accelerator of the present invention includes powders, granules, liquids and the like, which can be prepared by a conventional method using a solvent, a dispersion medium, a filler and the like. Further, in order to apply the chlorophyll formation promoter of the present invention to plants, it may be used for foliage treatment (foliage treatment agent) or for soil treatment (soil treatment agent). Further, it may be absorbed before planting or cutting and the like, or may be added to the culture solution during hydroponics.

When the chlorophyll formation promoter of the present invention is used in a culture solution such as a dipping solution or a spraying / spraying solution in hydroponics, the concentration of lepidimoid in the culture solution is not particularly limited, but is, for example, 1 to 10000 ppm. Preferably 1
It is about 0.00 to 1000 ppm. When used for soil treatment, the amount is, for example, about 3 to 30 g / m ² .

The chlorophyll formation promoter of the present invention is used in combination with other plant growth regulators such as plant hormones, sugars, amino acids, organic acids, alcohols, vitamins, minerals and other components commonly used in plant cultivation. be able to. These other components can be appropriately added to the culture solution or the like according to the formulation used for ordinary cultivation, depending on the type of plant to be applied.

The plant to which the chlorophyll formation promoter of the present invention is applied is not particularly limited as long as it is a plant that synthesizes chlorophyll, but lettuce, saladana, parsley, shungiku, spinach, cabbage, komatsuna, Chinese cabbage, leek. , Leafy vegetables such as Chinese chive, radish radish, honeywort, watercress and agar, and fruit vegetables such as tomato, eggplant, cucumber, pumpkin, watermelon and melon. In particular, plants cultivated indoors such as house cultivation and plant factories, such as lettuce, saladana, shungiku, parsley,
It is preferably applied to radish radish, honeywort, watercress, agar and the like.

(2) Treatment agent for indoor cultivated plant of the present invention The treatment agent for indoor cultivated plant of the present invention is characterized by containing the above-mentioned chlorophyll formation promoter of the present invention. The chlorophyll formation promoter of the present invention has a high effect of promoting chlorophyll synthesis even under weak light indoors, which has less light than outdoors, and can enhance the photosynthetic ability of plants.
It is suitable for use as a treatment agent for indoor cultivation plants such as house cultivation and plant factories.

Examples of the treatment agent for indoor-cultivated plants include a foliage treatment agent, a soil treatment agent such as a soil conditioner, and an additive to a culture solution for hydroponic culture. In addition to the chlorophyll formation promoter of the present invention, the treatment agent is used for other plant growth regulators such as plant hormones, sugars, amino acids, organic acids, alcohols, vitamins, minerals, etc. You may mix | blend the component of previously.

The treatment agent for indoor cultivated plants of the present invention is applied to lettuce, saladana, shungiku, parsley, kaiware radish, honeywort, watercress, seri which are plants cultivated indoors such as in the above-mentioned greenhouse cultivation and plant factories. Is preferred.

(3) Anti-aging Agent of the Present Invention The anti-aging agent of the present invention is characterized by containing lepidimoid as an active ingredient. Although the mechanism of action of lepizimoid in preventing senescence such as leaves, flowers, and physiological fruit drop is not clear, growth of the delamination formed between leaves (flowers, fruits) and stems promotes leaves, etc. It is considered that lepidimoid exerts an effect of preventing defoliation by inhibiting the formation of this delamination.

The method for obtaining lepidimoid may be either extraction from the above-mentioned natural product or chemical synthesis. The dosage form of the anti-aging agent of the present invention containing such a lepidimoid as an active ingredient includes powders, granules, liquids and the like, which are used in a conventional manner using a solvent, a dispersion medium, a filler, etc. It can be prepared. Further, regarding the application of the anti-aging agent of the present invention, for foliage treatment (foliage treatment agent), soil treatment (soil treatment agent), application to planting or cuttings of plants, for cultivation liquid of hydroponics, etc. Either is fine.

For example, when the defoliant-preventing agent of the present invention is used as a culture solution such as a dipping solution or a spraying / spraying solution in hydroponic culture, the concentration of lepidimoid in the culture solution is not particularly limited, but is, for example, 1 to 10000 ppm, More preferably 1
It is about 0.00 to 1000 ppm. The concentration of lepidimoid when used as a soil treatment agent is not particularly limited, but is preferably about 3 to 30 g / m ² .

The defoliant-preventing agent of the present invention may be used in combination with other plant growth regulators such as plant hormones, sugars, amino acids, organic acids, alcohols, vitamins, minerals and other components commonly used in plant cultivation. You can These other components can be appropriately added to the culture solution or the like according to the formulation used for ordinary cultivation, depending on the type of plant to be applied.

The plants to which the defoliant-preventing agent of the present invention is applied are not particularly limited, but lettuce, saladana, parsley,
Leaf vegetables such as shungiku, spinach, cabbage, komatsuna, Chinese cabbage, leek, Chinese chive, radish radish, honeywort, watercress, and acer, and fruit vegetables such as tomato, eggplant, cucumber, pumpkin, watermelon, and melon, and the like can be mentioned. By applying to these plants, it is possible to prevent foliage and the like to prevent plant aging, improve crop production efficiency, and reduce cost loss.

[0047]

Embodiments of the present invention will be described below.

[0048]

Example 1 In this example, the effect of increasing the chlorophyll content was investigated by adding the chlorophyll formation promoter of the present invention to seedlings.

(1) Synthesis of lepidimoid In this example, sodium salt of lepidimoid and carboxylic acid type lepidimoid were mixed with Kosemura, S., Yamamura, S.,
Kakuta, H., Mizutani, J., and Hasegawa, K., "Synth
esis and absolute configuration of lepidimoide, a
high potent allelopathic substance from mucilage o
f germinated cress seeds. "Tetrahedron Letters, 34
(16), 1993, p2653-2656, and according to the method described in JP-A-6-49089, D-glucose and L-
Rhamnose was synthesized as a raw material and used as a chlorophyll formation promoter.

(2) Measurement of increase in chlorophyll Sunflower seedlings germinated in the dark were irradiated with light (14 hours photoperiod, light amount 23 μmol / m ²⁾ on filter paper containing the test solution.
-The cells were cultured for 7 days under s (white fluorescent lamp), 25 ± 1 ° C. An aqueous solution of lepizimoid was used as the test solution. For comparison, a solution prepared by using an aqueous solution of benzyladenine, which is a kind of cytokinin known as a hormone that promotes the synthesis of sucrose or chlorophyll, was also prepared. The composition of the test solution is 300 ppm or 1000 ppm for lepizimoid and sucrose, respectively.
There are two types of benzyladenine, 10 ppm or 30 ppm (limit of dissolved concentration). Moreover, what used pure water as a control (Control) was prepared.

After culturing, chlorophyll was extracted from this seedling and the chlorophyll content was measured. That is, 12 ml of 80% cold (-15
℃) crushed in acetone (5-10 times the volume of seedlings),
After centrifugation at 12,000 g for 5 minutes at 4 ° C., the supernatant was collected with a Pasteur pipette and placed on ice. 12 ml of 80% cold acetone was added to the centrifugation residue, and the mixture was vortexed and centrifuged at 4 ° C. and 12000 g for 5 minutes.
The supernatant was collected with a Pasteur pipette and added to the previous collection solution. The recovered liquid was diluted with 80% cold acetone to 25 ml to prepare an extract, and the chlorophyll content was measured. The chlorophyll content is measured by Arno (Arno
n) According to the law.

The absorbance (D645nm, D663nm) was measured, and the calculation formula [20.2D645 + 8.02D66] was used.
3] was defined as the total chlorophyll content. The measurement result of the chlorophyll content is shown in FIG. In FIG. 1, LM represents a sodium salt of repidimoid in which R in the general formula (II) is Na, and CA-LM represents a carboxylic acid type repidimoid in which R in the general formula (II) is H. S represents sucrose and BA represents benzyladenine. Also, regarding the experimental results of each test solution, the left column has a concentration of 1000 ppm, the right column has a concentration of 300 ppm (benzyl adenine has a left column of 30 p.
pm, right column 10 ppm). As can be seen from FIG. 1, when lepizimoid is added to the test solution, the rate of increase in chlorophyll content is higher than that of benzyladenine, and there is a stronger chlorophyll synthesis promoting effect.

As a result of carrying out the same experiment by changing the concentration of lepidimoid, the effective minimum concentration of lepidimoid was 100.
It was found to be 1.5 times the chlorophyll content of the control (no addition = Control) in ppm.

[0054]

Example 2 In Example 1, the effect of promoting chlorophyll synthesis under weak light was examined by changing the light irradiation amount. That is,
The degree of increase in the chlorophyll content was measured in the same manner as in Example 1 (7 day culture / 14 hour photoperiod) except that the light irradiation amount to the seedlings was 11 μmol / m ² · s (white fluorescent lamp). The results are shown in FIG. In FIG. 2, LM is the general formula (I
The sodium salt of lepidimoid in which R in I) is Na is
CA-LM represents a carboxylic acid type lepidimoid in which R in the general formula (II) is H, and BA represents benzyladenine. Regarding the experimental results of each test solution, the left column has a concentration of 1000 ppm and the right column has a concentration of 300 ppm (benzyladenine has a left column of 30 ppm and a right column of 10 ppm).
From the results shown in FIG. 2, it can be seen that the addition of lepizimoid further increased the amount of chlorophyll synthesis and improved the photosynthetic ability, as compared with the case of no addition under normal illumination intensity.

[0055]

Example 3 In this example, the promoting effect of the chlorophyll formation promoter of the present invention on aminolevulinic acid (ALA) biosynthesis was examined.

The increase in chlorophyll due to the addition of lepidimoid is considered to be due to the promotion of the biosynthesis of aminolevulinic acid which is a precursor of chlorophyll. The quantitative determination of the amount of aminolevulinic acid synthesized is because the conversion of aminolevulinic acid to chlorophyll occurs instantaneously. The apparent content of aminolevulinic acid itself does not differ from that of the control when lepidimoid is added. However, the addition of levulinic acid, a competitive inhibitor of the conversion of aminolevulinic acid to chlorophyll,
The conversion of aminolevulinic acid to chlorophyll is inhibited,
It can be confirmed that the content of aminolevulinic acid increases with the promotion of chlorophyll synthesis.

Therefore, the test solution containing levulinic acid and lepidimoid (carboxylic acid type lepidimoid) was used to incubate the seedlings to examine the effect of lepizimoid on the biosynthesis of aminolevulinic acid. That is, 2 ml of sunflower seedlings cultivated in the dark for 5 days on a filter paper containing a test solution containing levulinic acid and lepidimoid
7 pieces each were placed in a 4.5 cm Petri dish containing pure water (MilliQ water) and irradiated for 14 hours (25 ± 1 ° C., 23 μ
mol / m ² · s). The concentration of lepidimoid in the test solution is 300 ppm or 1000 ppm,
The concentration of levulinic acid is 10 mM. For comparison, the same experiment was carried out using a test solution containing levulinic acid alone or lepidimoid alone and a control (Control: water).

Immediately after irradiation, aminolevulinic acid was extracted. That is, after measuring the fresh weight of 7 cotyledons, 5
Homogenize by adding ml of 4% TCA (trichloroacetic acid). This was centrifuged for 15 minutes, 1 ml of the supernatant was collected, 480 μl of 1M sodium acetate and 30 μl of acetylacetone were added thereto, and the mixture was boiled for 10 minutes. After cooling with water, an equal amount of Ehrlich reagent (DMBA: p-dimethylaminobenzaldehyde 1 g, 8 ml perchloric acid and acetic acid were added to make the total amount 50 ml) was added,
The absorbance (A553 nm) of this was measured to calculate the aminolevulinic acid content (mM / gFW). The results are shown in FIG. In FIG. 3, LA represents levulinic acid, ALA represents aminolevulinic acid, and CA-LM represents carboxylic acid type lepidimoid (concentration (ppm) in parentheses).

From the results shown in FIG. 3, it can be seen that the synthesis of aminolevulinic acid is promoted when the test solution containing levulinic acid and lepidimoid is used. On the other hand, since levulinic acid alone does not increase the content of aminolevulinic acid, it can be seen that it is lepidimoid that promotes the synthesis of chlorophyll precursor aminolevulinic acid.

[0060]

Example 4 In this example, the following experiment was carried out in order to investigate the effect of preventing defoliation due to delamination inhibition when the chlorophyll formation promoter of the present invention was used. That is, common bean (Phaseolus vulgaris L. cv. Mast
erpiece) is soaked in tap water for 2-3 hours, then germinated in sand washed with water, and continuous light (fluorescent lamp, 8W / m ² ) after germination
It was cultivated for 10 days at 25 ° C. under

An explant containing the first leaf was cut out from the kidney bean thus cultivated. Two sheets of filter paper (Toyo Filter Paper, No. 2) were laid on a sterilized 9 cm Petri dish, and 5 ml of a test solution containing a predetermined concentration (0, 1, 10, 100, or 1000 μM) of lepidimoid (carboxylic acid type) was added. The above-mentioned 10 to 16 explants were placed in a humidified incubator and cultured at 25 ° C. under continuous light (fluorescent lamp, 8 W · m ² ) for a predetermined time (60 hours or 48 hours).

After culturing, light pressure was continuously applied to the explants to count the number of individuals with cracks or the number of individuals with deciduous leaves, and the ratio to the total number of individuals was determined to be the delamination rate.
FIG. 4 shows the results. In FIG. 4, 60 h represents a measurement curve of 60 hours of culture, and 48 h represents a measurement curve of 48 hours of culture.

As can be seen from FIG. 4, when the case of irradiation for 60 hours was examined, the control group (repidimoid concentration 0%)
The delamination rate was 80%, but when the test liquid containing lepizimoid was used (1 μM or more), the delamination rate was remarkably reduced. When treated with 1 mM (1000 μM) lepizimoid, the delamination rate was 30%. A similar tendency was observed in the case of irradiation for 48 hours.

[0064]

Example 5 The following experiment was conducted in order to confirm that the chlorophyll formation promoter of the present invention has an effect of preventing chlorophyll reduction in the dark.

Oats (Avena sativa L. cv. Victory
I) is germinated in a moistened vermiculite and
Culturing was performed for 9 days under continuous light (fluorescent lamp, 8 W / m ² ) at ℃. The upper 3 cm leaf segment was cut out from the first seedling that had grown to approximately 15 cm. Of these, 15 leaf slices were randomly selected, and 2 sheets of filter paper (Toyo Filter Paper, No. 2) were laid on a sterilized 9 cm Petri dish, and 5 ml of the test solution was used.
Was added. Here, an aqueous solution containing lepidimoid (carboxylic acid type) was used as the test solution, and the concentrations were 0, 10, 30, 100, 300, and 1000 μM, respectively.
And The petri dish containing this leaf slice was cultured for 24 hours in the dark at 25 ° C. The leaf sections after culturing were stored at -80 ° C until the chlorophyll content was quantified.

Of the cultured leaf slices, 80 leaf slices were used.
Chlorophyll was extracted by boiling in ethanol at 60 ° C for 60 minutes. 10 ml of the obtained extract was added to ethanol at 80 ° C.
The absorbance of this product was measured at A665 nm. On the other hand, the chlorophyll content of fresh leaf slices before dark treatment was measured, and as the original chlorophyll content,
The residual rate (%) of the chlorophyll content after the culture was measured.
The experiment was repeated 3 times or more, and the average value was calculated and used as the measured value. Results are shown in FIG. As can be seen from FIG. 5, culturing by immersing leaf slices in a liquid containing lepidimoid prevents the reduction of chlorophyll.

[0067]

EFFECTS OF THE INVENTION By using the chlorophyll formation promoter of the present invention, it is possible to cultivate vegetables with a dark leaf color even under weak light, reduce the production cost in indoor cultivation, and improve the commercial value. be able to.

Further, by using the plant anti-aging agent of the present invention, it is possible to prevent fallen leaves and improve the production efficiency of crops.

[Brief description of drawings]

FIG. 1 is a diagram showing measurement results of chlorophyll content in Example 1.

FIG. 2 is a diagram showing measurement results of chlorophyll content under weak light in Example 2.

FIG. 3 shows aminolevulinic acid (AL in Example 3).
A) It is a figure which shows the measurement result of content.

FIG. 4 is a diagram showing a measurement result of a delamination formation rate in Example 4.

FIG. 5 is a diagram showing measurement results of chlorophyll residual ratio in Example 5 (after culturing for 24 hours).

Claims (5)

[Claims] 1. A chlorophyll formation accelerator comprising a repidimoid represented by the following general formula (I) or an analog thereof or a salt thereof as an active ingredient. Embedded image [In the formula (I), R ¹ , R ² , R ³ , R ⁴ and R ⁵ each independently represent a hydrogen atom, an acetyl group or a benzyl group, and R ⁶ is a hydrogen atom, a hydroxyl group, an acetoxy group or R ⁸ represents a benzyloxy group, R ⁷ represents a hydrogen atom, and R ⁶ and R ⁷ together may represent another direct bond, R ⁸
Represents a carboxyl group, an alkyloxycarbonyl group, a hydroxymethyl group or an acetoxymethyl group. ] 2. The chlorophyll formation accelerator according to claim 1, wherein the repidimoid, its analog or a salt thereof is a compound represented by the following general formula (II). Embedded image [In the formula (II), R represents a hydrogen atom, an alkyl group or an alkali metal element. ] 3. A treatment agent for indoor cultivated plants, which comprises the chlorophyll formation promoter according to claim 1 or 2. 4. A plant anti-aging agent comprising a repidimoid represented by the following general formula (I) or an analog thereof or a salt thereof as an active ingredient. Embedded image [In the formula (I), R ¹ , R ² , R ³ , R ⁴ and R ⁵ each independently represent a hydrogen atom, an acetyl group or a benzyl group, and R ⁶ is a hydrogen atom, a hydroxyl group, an acetoxy group or R ⁸ represents a benzyloxy group, R ⁷ represents a hydrogen atom, and R ⁶ and R ⁷ together may represent another direct bond, R ⁸
Represents a carboxyl group, an alkyloxycarbonyl group, a hydroxymethyl group or an acetoxymethyl group. ] 5. The plant anti-aging agent according to claim 4, wherein the repidimoid or its analog or a salt thereof is a compound represented by the following general formula (II). Embedded image [In the formula (II), R represents a hydrogen atom, an alkyl group or an alkali metal element. ]