JP5366474B2 - Gibberellin signaling pathway inhibitor for plants containing D-allose as an active ingredient and use thereof - Google Patents

Description

  The present invention relates to a plant gibberellin signal pathway inhibitor containing D-allose as an active ingredient, and makes it possible to control plant growth. Gibberellin (GA) is a plant hormone that controls plant germination, elongation growth, flower bud formation and the like. For example, rice SLR1 protein is a transcription factor that negatively regulates GA signal transduction, and it has been clarified that degradation of SLR1 protein depending on upstream GA signal is essential in various reactions caused by GA. . As a result of assaying the influence of D-allose on the gibberellin signal pathway using rice treated with D-allose, it became clear that D-allose can control the gibberellin signal pathway via an HXK (hexokinase) -dependent signal pathway. It was. The present invention makes it possible to control the growth of plants by utilizing such characteristics of D-allose. In the agricultural production technical field, for example, lodging by rice chiefs or excessive growth due to rice seedling disease is possible. It is intended to provide a useful drug capable of preventing rice and increasing rice yield.

  Gibberellin, a kind of plant hormone, is a general term for compounds having an ent gibberane skeleton, and plays an important role in various biological processes including stem / internode elongation (see Non-Patent Documents 1 and 2). ), And has been used in agriculture as a hormone that controls important characteristics of crops such as germination and dormancy. Internode elongation in rice is a typical model system for gibberellin signaling in monocots.

On the other hand, rice mutants eui (e longated u pper-most i nternode) denotes a phenotype which abnormally extending the internode Heading time. When the endogenous gibberellin content between the most elongated upper nodes of the eui plant was measured, abnormal accumulation of GA ₄ was observed compared to the wild type. Studies have been conducted on gene regions on the rice genome related to internode elongation at the time of heading rice, and gene regions related to internode elongation have been specified to some extent (see Non-Patent Document 3).

  Some rare sugars such as D-psicose, D-fructose, D-allose, L-galactose are effective as growth regulators of various plants, induce the expression of pest defense related genes such as rice, Was found to have growth-regulating activity. For example, a rare sugar is recognized as a foreign substance by a plant, and has a function of activating a plant resistance gene group to promote an increase in resistance against pathogenic bacteria and pests. An invention relating to a technique using a rare sugar such as D-psicose as a plant disease resistance amplifying agent has been patented (see Patent Document 1).

  In addition, for the purpose of providing agricultural chemicals using the effect of induction of systemic acquired resistance of plants, or the growth inhibitor of harmful microorganisms as well as plant pathogens, the effect of inducing acquired systemic resistance of plants Pesticides used, plant disease inhibitors, plant growth regulator inducers (disease resistance, insect resistance, fruit ripening, dormancy breaking, germination control, drought resistance, low temperature resistance, high temperature resistance, salt resistance, heavy metal resistance And the like, and an invention relating to use as a microbial growth inhibitor (see Patent Document 2). As the rare sugar, aldose (D-allose, D-altrose, or L-galactose) or ketose (D-psicose, or a mixture of D-psicose and D-fructose) is used.

Furthermore, for the purpose of providing a plant growth regulator and a plant growth regulator, an invention relating to a plant growth regulator comprising a rare sugar as an active ingredient is disclosed. As a rare sugar, a plant growth regulator using a rare sugar selected from the group consisting of D-psicose, a mixture of D-psicose and D-fructose, D-allose and L-galactose is disclosed (see Patent Document 3). ).
However, the mechanism of action of these rare sugars on plants has not been elucidated.

Japanese Patent No. 4009720 JP 2006-8669 A JP 2006-188482 A 161-188 (Elsevier Science B.V., 1999) Rev. Plant Biol. 55, 197-223 (2004) (2004) Mol. Gen. Genomics. 272, 149-155

  Under such circumstances, in view of the above prior art, the present inventors have clarified the mechanism of bioactive action of rare sugars on plants, thereby enabling useful plant growth regulators in the production process of agricultural crops. As a result of intensive research with the goal of developing a novel saccharide, D-allose has been found to have a plant gibberellin signal pathway inhibitory action among rare sugars, and further research has led to the completion of the present invention.

  The objective of this invention is providing the gibberellin signal pathway inhibitor of the plant which has D-allose as a main component. Another object of the present invention is to provide a plant growth suppression method and a growth inhibitor that suppresses growth by applying D-allose to a plant body in a scene where it is desired to suppress the gibberellin action in an agricultural scene. For example, it is possible to solve the problems related to the length and internode elongation caused by gibberellin secreted by rice sapling seedling fungus by treating D-allose with contaminated cocoons and plants.

  In addition, an object of the present invention is to provide a pesticide, a plant disease inhibitor, and a plant growth regulator inducer that uses the effect of inducing resistance to plant whole body acquisition, which may drastically reduce the amount of pesticide used. It is provided by using D-allose as an active ingredient. Further, the object of the present invention is to spray D-allose on seeds, plant roots, stems, leaves, flower tissues, cells, etc. in a solution state or in a solid state, soak the cutting base in the solution, soil An object of the present invention is to provide a method for suppressing plant growth, which is carried out by applying by a method such as irrigation. More specifically, the object of the present invention is to prevent the planting of rice by the head of rice, reduce the various effects of rice diseases, and increase the yield of rice. It is to provide a growth inhibitor.

  The present invention relates to a plant gibberellin signal pathway inhibitor characterized by comprising D-allose as an active ingredient, and the mechanism of action of D-allose is through the HXK-dependent signal pathway and the gibberellin signal pathway. Suppress. More specifically, D-allose inhibits the pathway from the SLR1 protein system to the α-amylase in the gibberellin signal pathway via an HXK-dependent signal pathway. The plant to which the present invention can be applied is not limited in its kind as long as it has a gibberellin signal pathway. Examples of plants to which the present invention can be applied include monocotyledonous plants, specifically, grasses, and more specifically, rice, wheat, barley, rye, oats, corn. , Sugarcane, ryegrass, Kentucky bluegrass, fescues, bentgrass, wild buckwheat, red mulberry, and Bermudagrass. In addition, the present invention is a plant growth inhibitor that suppresses the gibberellin signaling pathway of plants by D-allose. For example, it can be used as an inhibitor of plant growth caused by rice sapling seedling disease, or as a rice lodging inhibitor. it can.

  The present invention also relates to a method for suppressing the gibberellin signal pathway of a plant by applying the above-described gibberellin signal inhibitor to the plant body, for example, the root, stem, leaf, seed, bud, flower of the plant body. This is a method for inhibiting the gibberellin signal pathway in plants, which comprises applying D-allose to the tissues and cells. In applying D-allose to plants, D-allose is preferably applied in the form of a 0.01 to 20% by weight solution. Moreover, in order to apply D-allose to agricultural land, a culture medium, etc., it is preferable to set it as 0.1-1000 kg / ha, for example. Moreover, said plant is mentioned as an example of the plant which can apply the gibberellin signal pathway inhibition method of the plant of this invention. The present invention also relates to a method for inhibiting plant growth by inhibiting the plant gibberellin signal pathway. The present invention, among the plants exemplified above, particularly as a method for suppressing rice growth, suppresses the growth of rice afflicted with rice seedling disease, prevents the lodging of rice, and further suppresses the growth of turfgrass and its state It is a method to keep the proper.

The following effects are exhibited by the present invention.
D-allose is expected to be applied in the scene where it is desired to suppress GA action in agriculture using the inhibition of gibberellin (GA) signal pathway, and exhibits growth inhibitory action on plants with GA signal pathway can do. For example, rice sapling is caused by GA secreted by the pathogen, but it became possible to suppress the pupa by treating cocoons infected with the pathogen with D-allose.
Moreover, by applying D-allose to a plant body, it becomes possible to prevent lodging due to overgrowth and to prevent the growth of turfgrass. In particular, by applying the growth inhibitor of the present invention to rice, it is possible to reduce the symptoms of diseases such as infected rice seedling disease and to prevent lodging by the chief, thereby increasing the yield of rice. Be expected.

  In the present invention, as a result of elucidating the mechanism of action by examining various physiological actions regarding the relationship between D-allose (hereinafter also simply referred to as “allose”) and various plant hormone production / hormone signal pathways, -Allose is based on the finding that it inhibits the signal transduction system of plant hormones, especially gibberellins. Below, the outline | summary is demonstrated about the action mechanism of D-allose.

Gibberellin (GA) is a plant hormone that controls plant germination, elongation growth, flower bud formation and the like. In recent years, several factors involved in GA signaling have been identified from studies using Arabidopsis and rice mutants. Research on hormone systems that promote rice growth is progressing in GA research. For example, rice SLR1 protein is a transcription factor that negatively regulates GA signal transduction, and it has been clarified that degradation of SLR1 protein depending on upstream GA signal is essential for various reactions caused by GA. . Then, as a result of testing the signal pathway of D-allose action in rice treated with D-allose using various inhibitors of hexokinase (HXK), the action of D-allose may go through an HXK-dependent signal pathway. It became clear. Furthermore, as a result of examining the relationship between the action of D-allose and the GA pathway, rice that was inhibited from growth by treatment with D-allose was also inhibited from growth even if treated simultaneously with GA (gibberellin A ₃ ). Therefore, it was considered that GA production was not suppressed by D-allose.

  Therefore, in order to see the effect on the GA signal system, α-amylase activity, which is an activity indicator enzyme of the GA signal pathway, was measured, and as a result, suppression by D-allose treatment was observed. The action of D-allose is not complemented by the addition of GA, and α-amylase activity is inhibited, indicating that D-allose may inhibit the GA signal pathway. Furthermore, when assayed for the relationship with the SLR1 protein, GA promoted the degradation of the nuclear GA signal suppressor protein SLR1, and the GA signal pathway was activated by the degradation of the SLR1 protein. As a result of assaying the action of D-allose in slr1 rice, which is a mutant mutant of SLR1, D-allose exhibited a strong inhibitory action even in the slr1 strain showing a prominent trait due to SLR1 deficiency. From the above results and the test results using the defective mutant slr1, D-allose can inhibit the pathway from the SLR1 protein system to the α-amylase in the GA signal pathway via the HXK-dependent signal pathway. It became clear. The present invention is based on such knowledge.

Next, the present invention will be described in more detail.
The plant gibberellin signal pathway inhibitor and its inhibition method comprising D-allose according to the present invention as an active ingredient can be applied to any plant having a gibberellin signal pathway. More specifically, examples include rice, wheat, barley, rye, oats, corn, sugarcane, ryegrass, Kentucky bluegrass, fescue, bentgrass, wild buckwheat, damselfly, and Bermudagrass. it can.
In the present invention, among plants to which the present invention is applied, rice will be described in detail below as a typical example.

D-allose used in the present invention is a rare sugar that has been found to have various physiological activities in the research on rare sugars. D-allose (D-allohexose) is a D-form of allose classified as aldose (aldohexose), and is a hexose having a melting point of 178 ° C. (C ₆ H ₁₂ O ₆ ). As a production method of this D-allose, there is a production method by a method of reducing D-alonic acid lactone with sodium amalgam. Also, using L-rhamnose isomerase described in “Journal of Fermentation and Bioengineering” Vol. 85, pp. 539 to 541 (1993) by Sheikhwat Hossein Puiyang etc. A process for synthesizing from D-psicose is known. Furthermore, in recent years, as described in JP-A No. 2002-17392, there is a production method for producing D-allose from D-psicose by allowing D-xylose isomerase to act on a solution containing D-psicose. Proposed. According to the production method described in this document, production of D-allose is obtained as an enzyme reaction solution containing newly produced D-allose together with unreacted D-psicose.

  The type of enzyme used when converting a substrate that can be converted to D-allose into D-allose by an enzymatic reaction is not limited, but the enzyme “L-rhamnose isomerase” that can produce D-allose from D-psicose is available. Illustrated as preferred. L-rhamnose isomerase is an enzyme published in "Journal of Fermentation and Bioengineering", Vol. 85, 539-541 (1998). L-rhamnose isomerase, an enzyme that catalyzes the isomerization reaction from L-rhamnose to L-rhamnulose and the isomerization from L-rhamnulose to L-rhamnose, is also used for isomerization between D-allose and D-psicose. Since it acts, it is an enzyme that can produce D-allose from D-psicose.

  The plant disease control agent of the present invention mixed with D-allose or D-allose with other saccharides and the like may be used as it is, but is usually used by mixing with a carrier, and if necessary, a surfactant. , Wetting agents, sticking agents, thickeners, preservatives, coloring agents, stabilizers and other formulation aids are added, and wettable powders, flowable powders, granular wettable powders, powders, and emulsions are generally used. It is appropriately formulated by a known method and used.

  The carrier used in the present invention is a synthetic or natural inorganic or organic compounded to help reach the active ingredient allose to the site to be treated and to facilitate the storage, transport and handling of the active ingredient compound. It means a substance, and any solid or liquid can be used as long as it is usually used for agricultural and horticultural medicines, and is not limited to a specific carrier. For example, as a solid carrier, bentonite, montmorillonite, kaolinite, diatomaceous earth, white clay, talc, clay, vermiculite, gypsum, calcium carbonate, amorphous silica, ammonium sulfate and other inorganic substances, soy flour, wood flour, sawdust, wheat flour, Examples include plant organic substances such as lactose, sucrose, and glucose, and urea. Liquid carriers include aromatic hydrocarbons such as toluene, xylene, cumene and naphthenes, paraffinic hydrocarbons such as n-paraffin, iso-paraffin, liquid paraffin, kerosene, mineral oil, polybutene, acetone, methyl ethyl ketone, etc. Ketones, ethers such as dioxane and diethylene glycol dimethyl ether, alcohols such as ethanol, propanol and ethylene glycol, carbonates such as ethylene carbonate, propylene carbonate and butylene carbonate, aprotic solvents such as dimethylformamide and dimethyl sulfoxide, and water Is mentioned.

  Furthermore, in order to enhance the efficacy of the gibberellin signal pathway inhibitor containing D-allose of the present invention as an active ingredient, each of them can be used alone or in combination depending on the purpose in consideration of the dosage form and treatment method of the preparation. Adjuvants such as can also be used. As surfactants usually used for the purpose of emulsifying, dispersing, spreading and wetting in agricultural chemical formulations, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, sucrose fatty acid esters, polyoxyethylene fatty acid esters, Nonionic surfactants such as polyoxyethylene resin acid esters, polyoxyethylene fatty acid diesters, polyoxyalkylene adducts of higher alcohols, polyoxyethylene ethers, ester-type silicon, and fluorosurfactants; alkyl sulfates; Anionic surfactants such as polyoxyethylene alkyl ether sulfate, phosphatidylcholine, phosphatidylethanolimine, alkyl phosphate, sodium tripolyphosphate; acrylic acid and acrylonitrile, acrylic Polyanionic polymer surfactants derived from imidomethylpropanesulfonic acid; cationic surfactants such as alkyltrimethylammonium chloride, methylpolyoxyethylenealkylammonium chloride, alkyl N-methylpyridinium bromide, monomethylated ammonium chloride; dialkyldiamino Examples include, but are not limited to, amphoteric surfactants such as ethyl bentine and alkyl dimethyl benzyl bentine.

  Examples of the binder include sodium alginate, polyvinyl alcohol, gum arabic, CMC sodium, bentonite and the like. Examples of the disintegrant include CMC sodium and croscarmellose sodium, and examples of the stabilizer include hindered phenol-based antioxidants, benzotriazole-based, and hindered amine-based ultraviolet absorbers. Phosphoric acid, acetic acid, sodium hydroxide, etc. are used as pH adjusters, and industrial fungicides such as 1,2-benzisothiazolin-3-one, antibacterial fungicides, etc. are added for antibacterial and fungicidal purposes. The As the thickener, xanthan gum, guar gum, CMC sodium, gum arabic, polyvinyl alcohol, montmorillonite and the like are used. A silicone compound as an antifoaming agent and propylene glycol, ethylene glycol or the like as an antifreezing agent may be used as necessary. However, these components are not limited to those exemplified above.

  Examples of the application method of D-allose include, for example, spray treatment of plant bodies such as stems, leaves, and flower tissues and cells, seedling box treatment, spray treatment to the soil surface, and soil treatment after the spray treatment to the soil surface. Mixing, injection into soil, mixing of soil injected into soil, soil irrigation, mixing of irrigated soil, mixing into culture solution or medium, spraying onto plant seeds, coating onto plant seeds Splash treatment, soaking treatment on plant seeds or dressing treatment on plant seeds, spraying or soaking treatment on flowers, etc., but usually shows sufficient efficacy in any application method used by those skilled in the art To do.

  The dose of D-allose varies depending on the target crop, target disease, degree of disease occurrence, type of compound preparation, application method and various environmental conditions, but when spraying or irrigating, the amount of active ingredient in allose is hectares. 0.1 to 1000 kg per hectare is suitable, preferably 1 to 500 kg per hectare. The application concentration when sprayed with a solution is preferably 0.01 to 20% by weight. The amount used for seed treatment is 0.01 to 100 g, preferably 0.1 to 50 g, per 1 kg of seed. The application of D-allose is performed after dilution to an appropriate concentration with an appropriate carrier. For example, when D-allose is brought into contact with plant seeds, the plant seeds may be immersed in the D-allose solution as they are, but the amount of D-allose used is limited to these exemplified ranges. It is not a thing but can change with the form of a formulation, and the kind of plant seed used as a process target.

  The plant as used in the present invention includes all plants having a gibberellin signal pathway, and examples thereof include monocotyledonous plants. Specific examples include gramineous plants, and more specifically, rice, Mention may be made of wheat, barley, rye, oats, corn, sugar cane, ryegrass, Kentucky bluegrass, fescue, bentgrass, turkeys, cucumbers, and Bermudagrass. In addition, the “plant” in the present invention is a general term for all parts constituting a plant individual, and examples thereof include stems, leaves, roots, seeds, floral tissues, cells, protoplasts, and the like.

Next, the fact that D-allose inhibits the signal transduction system of plant hormones, particularly gibberellins, will be described in detail below based on experimental examples in comparison with D-psicose.
By labeling D-allose with D-psicose and ¹⁴ C and conducting experiments, it was clarified that both were incorporated into rice protoplasts. Therefore, research on kinetic analysis of uptake and metabolism after uptake into cells was advanced. As a result, ¹⁴ C-D-psicose and ¹⁴ C-D-allose uptake, respectively Vmax 313μg protein / hr, Km 19.3mM and Vmax 625μg protein / hr, were Km 46.0 mm, also ¹⁴ C-D- Psicose was not metabolized rapidly in rice cells, but ¹⁴ CD-allose was found to be phosphorylated.

  When rice is treated with D-psicose or D-allose, a large movement is observed in the gene expression behavior due to signal transmission to the nucleus, and further, a growth inhibitory action is observed. Therefore, the relationship between these rare sugar signals and a hexokinase (HXK) -dependent pathway or D-allose-independent pathway known as a glucose signaling pathway to the nucleus was clarified. As a result of investigating the effect on the action of rare sugars using D-Mannose, N-Acetyl-D-Glucosamine (D-GlucNAc) and D-Mannoheptulose which are HXK inhibitors, these inhibitors are all D-psicose. It did not inhibit the rice growth-inhibiting action by, but the action by D-allose was inhibited by these inhibitors in a concentration-dependent manner and the growth was promoted (FIG. 1).

  In addition, since only D-allose is phosphorylated after being taken into the cell, the action of D-psicose is transmitted through an HXK-independent signal pathway, but the action of D-allose is an HXK-dependent signal. It became clear that it went through a route (Fig. 2). It has been reported that the regulation of hormone signaling in Arabidopsis and the like differs greatly in HXK-dependent or independent signal pathways. From these results, it was considered that both rare sugars of D-allose and D-psicose show growth inhibitory action, but the mechanism of action in the cells until the growth inhibition is different.

Then, comparative examination was advanced about the relationship between D-psicose and D-allose, various plant hormone biosynthesis, and a hormone signal pathway.
In order to test the action of rare sugars on plant hormones, along with the absorption method from the roots used as a treatment method for rare sugars (the method of floating rice seedlings on the fifth day of sowing in a rare sugar aqueous solution and absorbing them from the roots) The microdrop method commonly used in gibberellin research was adopted. Even with this method, the specificity of the rare sugar was reproduced, and a strong growth inhibitory action was observed for D-psicose and D-allose (FIG. 3). In the case of the absorption method from the root, it was necessary to prepare a large amount of 0.5 mM aqueous solution for suppression, but in the microdrop method, it is sufficient to drop 1 μl of 100 mM aqueous solution between the cotyledon sheath and the first leaf. Thus, it has become possible to test the action of rare sugar in a small amount and with ease. The concentration of rare sugar used is 100 mM / L in the microdrop method, but since only 1 μl is used, the total amount used can be significantly reduced by this treatment method.

  When gibberellin (gibberellin A3, GA) is treated simultaneously with rice that has been subjected to growth inhibition by dropping rare sugars, the recovery of inhibition occurs in the D-psicose-treated group, but the recovery by GA is weak in the D-allose-treated group. It became clear (Fig. 4). Therefore, growth inhibition by D-psicose is related to inhibition of GA production (or inhibition of conversion to active GA, promotion of conversion to inactive GA) or other hormone signal systems closely linked to GA. Was suggested. On the other hand, with D-allose, strong growth inhibition was observed even in the GA-added group at a high concentration (100 mM), and recovery of inhibition as seen with D-psicose was not observed (FIG. 4).

At present, it has been elucidated that activated GA induces degradation of nuclear SLR1 protein, and activation of the GA signal pathway occurs by degradation of this protein. As an indicator of GA signal activation, induction measurement of α-amyloid activity is often used. Then, when the influence of rare sugars on α-amylase activity in embryoless half seeds was assayed, D-psicose had no effect on α-amylase activity induction, but D-allose showed an inhibitory action. Thus, D-allose action is not complemented by GA addition, and α-amylase activity is inhibited, indicating that D-allose may inhibit the GA signal pathway.
Thus, D-allose showed inhibition of α-amylase induction in the embryoless half-seed assay, suggesting inhibition of the GA signal pathway, but D-psicose did not show such activity.

As described above, it has been elucidated that, in rice, activated GA promotes the degradation of nuclear GA signal suppression protein SLR1, and the GA signal pathway is activated by the degradation of SLR1. Therefore, a test was conducted in which a rare sugar was allowed to act on slr1, which is a mutant mutant of SLR1. As a result, D-allose also showed a strong inhibitory action, and D-psicose also showed a suppression in the slr1 strain exhibiting a prominent trait due to SLR1 deficiency (FIG. 5). From the above results and the results using slr1, it is clear that D-allose inhibits the pathway from the SLR1 proteolytic system to the α-amylase in the GA signal pathway via the HXK-dependent signal pathway. (FIG. 6).
On the other hand, D-psicose recovers by GA addition although the inhibitory effect is not perfect (FIG. 4). In addition, since it does not affect the induction of α-amylase, suppression of GA production (including inhibition of conversion to active GA and promotion of conversion to inactive GA) occurs, and there is no inhibition in the GA signal pathway. I thought. However, D-psicose also suppressed the slr1 mutant length (FIG. 5). From this, it was considered that D-psicose does not directly act on GA production or GA signal pathway, but affects other hormone signaling pathways linked to GA.

  Next, although the detail of this invention is demonstrated based on an Example, this invention is not limited at all by these Examples.

(Rice laboratory test)
In this example, the effect of adding gibberellin on the rice growth inhibitory action of D-allose was examined. Rice seeds (rice cake) of the cultivar Nipponbare were planted in agar containing 10 to 1000 mg / L of rare sugar and 0.1 to 25 mg / L of GA3 (gibberellin), and the plant height on the seventh day after sowing was investigated. The result is shown in FIG. The growth-inhibiting action of D-allose was clearly observed at a concentration of about 10 mg / L or more of D-allose. It was revealed that the growth promoting action of GA3 was completely abolished in a medium containing about 100 mg / L or more of D-allose. On the other hand, in D-psicose, the effect of the effect of promoting the growth of gibberellin which coexists even under such high concentration conditions is noticeable.

(Growth inhibition test during rice seedling)
In this example, a test was conducted to clarify the effect of treatment with D-allose on the initial growth of rice. 6 seeds of rice (variety: Nipponbare) were planted in a 4 x 4 cm pot, and after 5 days of sowing and irrigation with 5 mL of D-allose aqueous solution, 5 individuals were randomly selected on the 25th day. The roots and leaves were examined for growth conditions. The amount of D-allose for the irrigation treatment was adjusted to 4 to 62.5 kg / ha, and a sample without D-allose was used as a control example.

  The test results are shown in FIG. For example, as a result of measuring the fourth leaf height, when the leaf height is 100% without D-allose treatment, about 89% is applied at 4 kg / ha, about 90% at 25 kg / ha is applied at 10 kg / ha. Growth was suppressed to about 82% by application of ha and about 79% by application of 62.5 kg / ha. On the other hand, when the length and weight of the roots were measured, in the range of application rates tested, by applying allose, root lengths of 92 to 119% with no treatment were obtained, and the root weight was 113. A value of ˜127% was obtained.

  As can be seen in FIG. 8, by performing the D-allose treatment, the fourth leaf height, third leaf height, and third sheath height of rice were lowered, and the weight of the dried stem was suppressed. However, with D-allose treatment, the root length and root dry weight showed a slight increase or the same value as compared to the untreated seedling. Thereby, it became clear that the growth inhibitory action by D-allose mainly affects only the above-ground part of a stem and a leaf. It was also revealed that the growth inhibitory effect was enhanced as the application amount of D-allose was increased.

(Rice field spray test)
In this example, the growth inhibitory effect on rice when D-allose is sprayed is shown by experiments.
After soaking and germinating rice (variety: Kofu), the seedlings were grown in a seedling box for 2 weeks and planted in rice. A solution prepared to a concentration of 5% by weight of D-allose was sprayed on the stems and leaves 20 days after rice planting at a volume of 200 L per 10a. The growth state 10 days after spraying is shown in FIG. The plant height of rice in the D-allose sprayed area was about 70% of that in the untreated area, and a remarkable growth inhibitory effect was observed.

(Rice field water treatment test for rice)
In this example, the growth-inhibiting effect on rice when D-allose is treated with paddy water is shown by experiments.
After soaking and germinating rice (variety: Kofu), the seedlings were grown in a seedling box for 2 weeks and planted in rice. A solution prepared to have a concentration of 5% by weight of D-allose in the rice surface water 20 days after rice planting was treated to 32 kg per 10a. The growth state 10 days after spraying is shown in FIG. The plant height of rice in the D-allose sprayed area was about 90% of that in the untreated area, and a remarkable growth inhibitory effect was observed.

(In-house test for rice idiot)
In the present Example, the control effect of the rice seedling disease by the drip treatment to a rice individual was examined. After seeding rice (variety: Tan Ginbo) with healthy cocoons and idiot-bearing fungi, seedlings grown for 3 days were used for the test. FIG. 11 shows the plant height of rice after 10 days after instilling 1 μL of an aqueous solution containing 0.1 to 5% by weight of D-allose on the leaf sheath of rice. In the growth of rice treated with D-allose, the length of gibberellin produced by the rice sapling fungus was significantly suppressed.

(Examination at the time of rice idiot seedling raising)
In this example, the control of rice seedling disease by irrigation treatment at the time of sowing was examined. After irrigating 10 mL of 1, 0.5, 0.1% by weight D-allose aqueous solution in a 5 x 5 cm pot filled with soil, germinate rice seedlings with rice seedling disease (variety: short silver shaved) 4g was seeded per pot. This was grown at 28 ° C. for 2 days and at 25 ° C. for 14 days, and then the plant height was examined to determine the proportion of diseased individuals. D-allose aqueous solution 1, 0.5, 0.1% by weight The treatment rates of the treated group and untreated group were 17.9, 29.7, 33.3, 71.8%, respectively, and D-allose was irrigated It was possible to suppress the rice chief due to gibberellin produced by the rice sapling fungus.

(Growth inhibition test in plants other than rice)
This example shows growth inhibition by D-allose using Taenobie, barley, corn, Italian ryegrass, and bentgrass, which are plants of the family Gramineae other than rice.
Pots were planted with cereals, barley, corn, Italian ryegrass and bentgrass, and 11 days after sowing, the plants were sprayed with a D-allose aqueous solution having a maximum concentration of 1% by weight and a minimum concentration of 0.0156% by weight. FIG. 12 shows the results of investigation on growth inhibition obtained by measuring the weight of the ground part 25 days after spraying.

  The result of comparing the ground weight after 25 days of spraying with the untreated section as 100% is, for example, about 22% for Tainubier, about 62% for barley, about 62% for corn and about 0.5% for D-allose. A value of 73%, about 42% for Italian ryegrass, and about 28% for bentgrass were obtained. Further, even when 0.0625% by weight of D-allose was sprayed, Tainubier and bentgrass had a sufficient growth inhibitory effect.

The present invention controls D-allose, which is a monosaccharide consisting only of carbon, oxygen, and hydrogen, in various scenes, without containing harmful elements by organic synthesis like conventional agricultural chemicals. By using it as a drug having an action, it provides a new technology useful for improving agricultural production technology. Since D-allose can suppress the GA signal pathway of plants, it is expected to be applied in scenes where it is desired to suppress GA action in agriculture, and various controls are performed on all plants having the GA signal pathway. Became possible. For example, rice sapling seedling disease is caused by GA secreted by pathogenic bacteria, but by treating D-allose with contaminated rice cake, the pupa can be suppressed. Moreover, by applying D-allose to a plant body, it becomes possible to prevent elongation due to excessive growth and to prevent elongation by applying it to turfgrass. In particular, by applying the growth inhibitor of the present invention to rice, for example, it is possible to reduce symptoms of infectious diseases and prevent lodging by a chief, and an increase in rice yield is expected.
The present invention makes it possible to control the growth of plants using the characteristics of D-allose and is useful in the field of agricultural production technology.

It is drawing which shows the influence with respect to the growth effect | action of the plant which applied rare sugar of the hexokinase (HXK) inhibitor. It is the schematic which shows the difference in the effect | action with respect to a plant of D-psicose and D-allose. It is drawing which shows the influence on the growth of rice at the time of applying rare sugars, such as D-allose, to a rice by microdrop method. It is a figure which shows that addition of gibberellin complements the action of D-psicose and does not affect the action of D-allose. This is a photograph in place of a drawing showing that the progeny of the SLR1-deficient mutant slr1 is strongly suppressed by D-allose treatment, but is also suppressed by D-psicose treatment. FIG. 4 is a schematic diagram showing that D-allose affects the pathway from the DELLA protein system of the GA signal pathway to α-amylase via the HXK-dependent signal pathway. It is drawing which shows the influence of the addition of gibberellin with respect to the growth inhibitory effect of rice by D-allose and D-psicose. It is the figure which compared the growth of the root and leaf of a rice which applied D-allose in the ratio of 0-62.5 kg / ha. It is the photograph replaced with drawing which shows the growth suppression of rice when 10 days passed after spraying 5% D-allose. It is the photograph replaced with drawing which shows the growth suppression of the rice at the time of having passed 10 days after processing D-allose in the amount of 32 kg / 10a to Ta surface water. It is a photograph replaced with drawing which shows the growth state after carrying out D-allose treatment of the rice sapling seedling blight. It is drawing which shows the growth suppression measured when 25 days passed, after spraying D-allose to five kinds of gramineous plants.

Claims (13)

  A plant gibberellin signal pathway inhibitor characterized by comprising D-allose as an active ingredient.   The plant gibberellin signal pathway inhibitor according to claim 1, which inhibits the gibberellin signal pathway via an HXK-dependent signal pathway.   3. The plant gibberellin signal pathway inhibitor according to claim 1 or 2, which inhibits the pathway from the SLR1 protein system to the α-amylase in the gibberellin signal pathway through the HXK-dependent signal pathway.   The plant gibberellin signal pathway inhibitor according to any one of claims 1 to 3, wherein the plant is a plant having a gibberellin signal pathway.   The plant gibberellin signal pathway inhibitor according to any one of claims 1 to 4, wherein the plant is a monocotyledonous plant.   The plant gibberellin signal pathway inhibitor according to any one of claims 1 to 5, wherein the plant is a gramineous plant.   The plant is a plant selected from the group consisting of rice, wheat, barley, rye, oats, corn, sugarcane, ryegrass, kentucky bluegrass, fescue, bentgrass, wild buckwheat, peony, and bermudagrass. 5. The plant gibberellin signal pathway inhibitor according to 5 or 6.   A method for inhibiting a gibberellin signal pathway in a plant, comprising applying the gibberellin signal inhibitor according to any one of claims 1 to 7 to a plant body. The method for inhibiting a gibberellin signal pathway of a plant according to claim 8 , wherein the plant is a root, stem, leaf, seed, bud, flower tissue, or cell. The method for inhibiting a gibberellin signal pathway in plants according to claim 8 or 9 , wherein D-allose is a 0.01 to 20% by weight solution. The method for inhibiting a gibberellin signal pathway of a plant according to any one of claims 8 to 10 , wherein D-allose is applied in an amount of 0.1 to 1000 kg / ha. The said plant is a monocotyledonous plant, The gibberellin signal pathway suppression method of the plant as described in any one of Claim 8 to 11 . The plant is rice, wheat, barley, rye, oats, corn, sugarcane, ryegrass, Kentucky bluegrass, fescue, bentgrass acids, Zoysia japonica, Zoysia tenuifolia, and from the claims 8 selected from the group consisting of Bermudagrass 1 3. The method for inhibiting a gibberellin signal pathway in a plant according to any one of 2 above.