JP2003321309A - Weed control agent for nonfarm land and its production method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a weed control agent having a high versatility, environmentally friendly, non-toxic, surely suppressing the growth of weeds, capable of enhancing the convenience and living environment of nonfarm lands, and having little effect and safe on the human body. <P>SOLUTION: There is provided a weed control agent for nonfarm lands including cinnamic acid, and a method for production thereof is also provided. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a weed inhibitor for suppressing the growth of weeds. More specifically, in non-agricultural land such as parks, riverbeds, roads and factory sites, it is effective in suppressing the growth of weeds that significantly reduces convenience and living environment, and is a safe and reliable weed inhibitor for non-agricultural land and its It relates to a manufacturing method.

[0002]

2. Description of the Related Art Conventionally, various herbicides have been used for the above-mentioned measures against weeds in non-agricultural land. There are several types of herbicides such as phenol type, diphenyl ether type, acid amide type, triazine type, carbamate type and phenoxy type, but most of them have been reported to be mutagenic or have harmful decomposition metabolites such as nitroso compounds. It has a considerable toxicity to humans and animals due to concern about the production of Among these herbicides, many have been suspected as environmental hormones and have been disputed. The use of such herbicides causes problems in terms of residual toxicity and environmental pollution.

On the other hand, as a measure against weeding that is relatively safe for the human body and the environment, there is the use of film-like (covering) mulch materials, which are systems for weeding with various light-shielding materials, Is limited, and it takes a lot of time to lay it. Moreover, although the liquid mulching agent can be used relatively easily, it is effective for paddy fields because it uses water as a medium, but is not suitable for non-farmland. There is also a method of using birds such as duck, but in this case as well, weeding was limited to paddy fields. Therefore, it is environmentally friendly, safe for the human body,
Moreover, a highly versatile weed countermeasure that can be used in a wide range has been desired.

[0004]

The present invention has been made in view of the above circumstances, and an object of the present invention is to have high versatility, be environmentally friendly, have no toxicity, and ensure the growth of weeds. The purpose of the present invention is to provide a safe weed control agent which can suppress the above-mentioned problems, enhance the convenience of non-agricultural land and the living environment, and have a small effect on the human body.

[0005]

Means for Solving the Problems As a result of intensive studies for achieving the above-mentioned object, the present inventors have found that cinnamic acid satisfactorily suppresses the growth of weeds and completed the present invention. Came to. That is, the present invention provides a non-farmland weed suppressant characterized by containing cinnamic acid and a method for producing the same.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to the following preferred embodiments. The cinnamic acid used as a weed suppressor in the present invention is a plant-related naturally-occurring substance and also a food additive, and thus is a substance having extremely high safety. Cinnamic acid also has an antibacterial and antifungal action (Japanese Patent Application Laid-Open No. 5-117125 and Japanese Patent Application Laid-Open No. 8-125125).
No. 259408), the weed suppressant of the present invention is effective not only for weed control but also for maintaining environmental hygiene.

In the present invention, weeds to be suppressed include:
For example, annual weeds include Nobies, Cyperaceae, Crabgrass, Acacia, Chickweed, Astragalus, Poa annua, and the like.For perennial weeds, Japanese pampas grass, Japanese oyster grass, Japanese knotweed, mugwort, Solidago mytilus, Reed,
Examples include bamboo grass, horsetail, and pine nuts. The weed suppressor of the present invention is generally effective against any of these weeds, but is particularly effective against grass weeds such as Nobies and Crabgrass and weeds of Oxalis.

In general, herbicides, when in direct contact with plants,
It is classified into a contact type in which the part is withered, and a transfer type in which the herbicidal component is absorbed into the leaves and stems and the drug is transferred to gradually show the herbicidal effect. A contact-type herbicide is a system that stays in the contacted area and exerts an effect only on that area, causing it to die. Generally, the herbicide is highly toxic and its safety to the human body and the environment becomes a problem.

On the other hand, the transitional herbicide (drug) is
It does not kill the plant from the contact area, but acts as a physiological substance that affects hormone balance etc., so it is relatively less toxic to other living organisms, safer than conventional herbicides, and less environmentally burdensome .

The weed-suppressing agent of the present invention belongs to this category, in which cinnamic acid as the main component is a food additive, and as a mutagen or an endocrine disrupter found in other transitional herbicides. Since no doubt has been acknowledged, it is extremely safe. The weed suppressor of the present invention causes abnormal growth of plants such as 2,4-D (2,4-dichlorophenoxyacetic acid) and MCP (2-methyl-4-chlorophenoxyacetic acid) among transitional herbicides. It is presumed that the weed-suppressing effect is expressed by a mechanism similar to that of the hormone-type herbicide that exerts the herbicidal effect. In other words, cinnamic acid disrupts the action of auxin, which is a plant hormone involved in cell division and elongation, resulting in suppression of cell division, inhibition of chlorophyll formation, abnormal increase in respiratory action, etc. It is presumed that the weed-suppressing effect is exhibited by the collapse and abnormal growth.

The weed-suppressing agent of the present invention can be applied, for example, by spraying it in various forms on a plant, or by dipping the roots or stems of the plant in an aqueous solution or dispersion of the plant, or when the plant originally has roots. By sucking up an aqueous solution or dispersion of cinnamic acid present in the vicinity, it acts as a transitional weed suppressor. The transfer-type drug is absorbed from the foliage and roots and transferred inside the plant to exert its effect. After spraying, it migrates to the whole plant, so some unevenness is allowed.

The use form of the weed suppressor of the present invention is not particularly limited, but cinnamic acid, which is the above-mentioned weed suppressor, may be used as a powder or granules which are easily dispersible in water. The substance is used in a liquid form such as a solution, emulsion, dispersion or suspension in which the substance is dissolved, emulsified, dispersed or suspended in water or another solvent.

When it is used as a liquid, it may be diluted in advance to a predetermined concentration, or may be diluted as a concentrated liquid before use. Further, if necessary, they can be used by mixing with a spreading agent, other herbicides, other additives and the like. Further, it can also be used as a powder in which the above weed-suppressing substance is supported on a carrier such as cyclodextrin, zeolite or silica.

The use amount of the weed suppressor of the present invention is not particularly limited, but a particularly effective use amount is 0.05 to cinnamic acid.
The absolute amount of cinnamic acid is 0.5 to 3 in 1 m ² of a solution, emulsion, dispersion or suspension containing 5.0 wt% concentration.
It is desirable to apply it so that the amount becomes 50 g. If the concentration is too low, the sufficient effect may not be exhibited, and if the concentration is too high, the surrounding environment may be adversely affected.

The aqueous dispersion as the weed control agent of the present invention can be produced by a generally known dispersion method using a dispersant. For example, cinnamic acid is mixed with a dispersant and water, the mixture is put into a vessel of a disperser such as a sand mill, and dispersed for about 3 hours at a rotation speed of about 120 rpm to obtain a weed suppressor of an aqueous dispersion. To be

The sand mill used in the present invention is
A small diameter (0.2-5.
(0 mm) spherical particles are filled to 30 to 95% of the internal volume, and a rotating mechanism for stirring the dispersion medium is further provided inside the container. The volume of the cylindrical container is 0.3 to 250 liters, and as a material, for example, stabilized zirconia, alumina, rubber or the like is preferable, and as a material for the dispersion medium, for example, stabilized zirconium, alumina, glass beads or the like is used. Can be used. As the use conditions, the rotation speed is 300 to 3,000 rpm, and the slurry supply amount of cinnamic acid is 0.2 to 5,000 ml / min.
Therefore, it is desirable to pass the disperser a plurality of times as necessary.

As the aqueous medium, water or a mixed solvent of water and an organic solvent such as water-soluble alcohols, ketones, esters and ethanolamines is used, and water is particularly preferable. The average particle size of cinnamic acid and the like is not particularly limited, but is preferably 3 μm or less.

As the dispersant used in the present invention, any dispersant can be used as long as it is a dispersant used in an aqueous medium. For example, a natural product system, an inorganic compound system, a polymer system or a special activator system is used. As a natural product system,
For example, lignin sulfonate, carboxymethyl cellulose (CMC), etc., inorganic compounds such as condensed phosphates such as hexametaphosphate, and polymers such as polyacrylate, acrylic acid. Examples thereof include salts of maleic acid copolymers and salts of olefin-maleic acid copolymers. As a special activator,
For example, an alkyl diphenyl ether disulfonate or a polycyclic special nonionic activator is used.

As an aqueous dispersant, various anionic, cationic, nonionic or amphoteric surfactants derived from natural products are used. Examples of the anionic surfactant include sulfated salts and sulfated salts of oils and fats such as castor oil, rapeseed oil and olive oil, aerosol type surfactants obtained by adding sulfuric acid to an ester of maleic acid and a higher alcohol, and fatty acid. Amidosulfated salt obtained by condensing chloride and taurine which is amine sulfonic acid,
Examples thereof include naphthalene-based sulfated salts and α-olefin sulfated salts.

Examples of the cationic activator include primary to tertiary amine salts such as alkylamine acetate, alkylamine hydrochloride and alkyldiethanolamine salt, and quaternary ammonium such as alkyldimethylbenzylammonium chloride. Examples thereof include salts and pyridinium salts.

As the nonionic activator,
For example, aliphatic polyoxyethylene esters such as fatty acid esters of polyhydric alcohols such as glycerin, sorbitol, sorbitan, sucrose, higher alcohols, alkylphenols, castor oil, polyoxyethylene ethers such as polyoxypropylene, sorbitol, sorbitan fatty acids. Examples thereof include ethylene oxide polymerization addition type activators such as ester polyoxyethylene adducts, and fatty acid alkylol amide type activators such as monoethanolamine condensates and diethanolamine condensates.

Examples of the zwitterionic activator include amino acid activators such as betaine activator, dodecyldiaminoethylglycine hydrochloride, N-tetradecyl taurine soda salt and the like. Among the above-exemplified dispersants, particularly preferable are dispersants of natural products such as lignin sulfonate and CMC, which are less likely to cause environmental pollution.

In carrying out the present invention, for example, a pure content of 3
An aqueous dispersion of cinnamic acid or the like at about 0% by weight is prepared, and diluted to about 6 to 600 times before use. Further, in the case of an aqueous dispersion of cinnamic acid having a pure content of about 10% by weight, it is diluted about 2 to 200 times before use.

The high-concentration aqueous solution of cinnamic acid, which is the weed-suppressing agent of the present invention, is characterized in that cinnamic acid is dissolved in water at a concentration exceeding its saturated solubility (maximum solubility) at 25 ° C. in water. . Such an aqueous solution can be produced by using a water-soluble solubilizing agent.

The solubilizing agent used in the present invention may be any salt or base of a weak acid and a strong base whose aqueous solution exhibits alkalinity, but exhibits a pH buffering action,
It is preferable to use one that is less likely to cause environmental pollution and safe for the human body. Examples of the salt of a weak acid and a strong base include sodium tripolyphosphate, potassium tripolyphosphate, sodium polyphosphate, potassium polyphosphate, 3 sodium phosphate, 3 potassium phosphate, 2 potassium hydrogen phosphate, 2 sodium hydrogen phosphate, carbonic acid. Preferable examples of potassium, sodium carbonate, sodium acetate, potassium acetate and the like, and preferable examples of the base include sodium hydroxide, potassium hydroxide and the like. As particularly preferable solubilizing agents, sodium tripolyphosphate, potassium hydroxide, potassium carbonate, sodium acetate and the like which are designated as food additives are used.

When a high-concentration aqueous solution of cinnamic acid is prepared, a high-concentration aqueous solution of cinnamic acid can be easily obtained by preparing an aqueous solution of a solubilizing agent in advance, adding cinnamic acid to this, and mixing them well to dissolve them. You can The amount of the solubilizing agent used is not particularly limited, but is preferably an amount of 35 to 300% by weight with respect to cinnamic acid and the like.

By using the solubilizing agent in this way, a high-concentration aqueous solution having a cinnamic acid content of 25% by weight or less is obtained, which exceeds the maximum solubility in water at room temperature. The preferable concentration is 0.5 to 25% by weight from the viewpoint of the storage space of the high-concentration aqueous solution and the transportation efficiency.

The weed control agent of the present invention comprising a high-concentration aqueous solution of cinnamic acid is used as a rough guide, for example, by preparing a high-concentration aqueous solution having a pure content of about 10% by weight.
It is used after diluting about 200 times.

[0029]

EXAMPLES Next, the present invention will be described more specifically with reference to examples. In addition, “%” in the text is based on weight, and the amount of cinnamic acid used is 1 total amount of the aqueous solution or the dispersion diluted liquid.
The amount is based on 00 parts by weight.

Example 1 (Preparation of 1% Diluted Solution of Cinnamic Acid Aqueous Dispersion) Preparation of Cinamic Acid Aqueous Dispersion: 160 g of cinnamic acid, dispersant (“Sun Extract” manufactured by Nippon Paper Industries Co., Ltd., sodium lignin sulfonate) 80 g and 293 g of water are mixed, and further 1,800 g of glass beads (diameter 1 to 1.25 mm)
Was added to this, and this was placed in a vessel of a disperser (a parallel 6-cylinder test sand mill manufactured by RM Co., Ltd.) and dispersed for 3 hours at a rotation speed of 120 rpm to obtain a cinnamic acid aqueous dispersion having a pure content of 30%. (The average particle size of cinnamic acid was 0.3 μm). Next, this dispersion was diluted 30 times with distilled water, and 1
% Cinnamic acid aqueous dispersion dilution was obtained.

(Fleet growth inhibition test) Planter (length:
Cultivation soil (“Math flower soil” manufactured by Emata Co., Ltd.) was placed in 30 cm × width: 15 cm × height 20 cm) to a depth of 10 cm. 4g of ground fly (Panicum Cr
seeds of us-galli L. var. frumentaceum Trin.) were sowed, and soil was lightly applied on the seeds. This planter was placed on the premises of Tokyo Manufacturing Office of Dainichiseika Co., Ltd.

After standing for 7 days, when the seeds germinated and the seedling became 5 cm long, the above 1% cinnamic acid aqueous dispersion diluted solution 30
0 ml was evenly sprayed over the soil in the planter to give a planter containing the cinnamic acid aqueous dispersion diluted solution. After standing for another 7 days, the plants in this planter were collected, and the soil adhering to the plants was removed, and then the dry weight (dry conditions are shown in Table 1).
Described in 1.) was measured.

For comparison, a planter treated in the same manner as the cinnamic acid aqueous dispersion diluted solution-added planter was prepared except that 300 ml of water was sprinkled, and used as a control planter. Plants grown in this control planter were prepared. The dry weight of the body was also measured. The results are shown in Table 1 below.

As shown in Table 1 below, when the dry weight of the millet plant in the control planter is 1, the dry weight of the millet plant in the planter containing the 1% cinnamic acid aqueous dispersion diluted solution is 0.35 to 0. It is 0.53, and the 1% cinnamic acid aqueous dispersion diluted solution clearly has a spinach growth inhibitory effect.

[0035]

Example 2 1 m x 1 in an open space in the Tokyo Factory of Dainichiseika Kogyo Co., Ltd.
^Two test areas of m (1 m ² ) were provided. One location was for the cinnamic acid aqueous dispersion diluted solution addition area, and the other location was for the control area, and a buffer zone having a width of 30 cm was provided between the addition area and the control area. Example 1 after once removing all the weeds in the test site
The test was started by spraying 1,500 ml of a 1% cinnamic acid aqueous dispersion diluted with 1% (cinnamic acid content 15 g / m ² ) on the addition section.

On the 14th day from the start of the test, 1,500 ml of 1% cinnamic acid aqueous dispersion diluted again (cinnamic acid content: 15 g)
/ M ² ) was sprayed on the addition section. When the diluted solution of the cinnamic acid aqueous dispersion was sprayed on the addition group, the same amount of water was sprayed on the control group for comparison.

72 days after the start of the test, the weeds grown in the two test plots were collected, washed with water, and the dry weight (drying conditions shown in Table 1) was measured. The results are shown in Table 2. Table 2
As shown in, when the dry weight of weeds in the control area is 1,
% Weighed dry weight of cinnamic acid aqueous dispersion diluted solution was 0.1
It is 3 to 0.14, and obviously, the 1% cinnamic acid aqueous dispersion diluted solution has a herbicidal effect.

[0039]

Example 3 40 g of pumice (average particle diameter of about 5 mm) was put in a container for plant cultivation (“Agripot” manufactured by Kirin Brewery Co., Ltd .: diameter 7 cm, height 11 cm), and the pure content shown in Example 1 was added. 30%
30 ml of a cinnamic acid aqueous dispersion diluted solution having a predetermined concentration (Table 3) prepared by diluting the cinnamic acid aqueous dispersion of 1. with water was added.

Then, on the surface of the pumice stone layer, the millet (Poaceae),
Spread the seeds of Western grass (Evergreen Lawngrass, Gramineae) and Radish (Convolvulaceae),
These containers are prefabricated indoor aluminum greenhouses (440 mm x
840 mm × 1500 mm) and cultivated at 25 ° C. for 10 days under a continuously lit fluorescent lamp (about 1,500 lux).

After cultivation, the amount of bud elongation of each plant was measured.
For comparison, when only water was added instead of the cinnamic acid aqueous dispersion diluted solution (control 1), only the dispersant aqueous solution (1%, sodium lignosulfonate aqueous solution) was not included (cinnamic acid not included).
The same experiment was performed for the case of adding (control 2). The results are shown in Table 3. From the results in Table 3, the herbicide-inhibiting effect of the cinnamic acid aqueous dispersion diluted solution was clarified.

[0043] * 1 = average value of 10 arbitrary samples * 2 = no germination.

Example 4 (Preparation of 0.5% cinnamic acid diluted mixed aqueous solution) At 20 ° C., 18.4 g of potassium hydroxide was dissolved in 400 ml of distilled water,
To this, 50 g of cinnamic acid was added, stirred and dissolved, and the total amount was adjusted to 500 ml with distilled water to prepare a cinnamic acid / potassium hydroxide mixed aqueous solution (pH 8.8) having a cinnamic acid pure content of 10%. Next, dilute this mixed aqueous solution 20 times with distilled water,
A diluted mixed aqueous solution having a cinnamic acid pure content concentration of 0.5% was prepared.

(Weed growth inhibition test) Dainichi Seika Kogyo Co., Ltd.
^Two test areas of 1 m × 1 m (1 m ² ) were set up in the open space of the Tokyo manufacturing facility. One location was for the cinnamic acid diluted mixed aqueous solution addition section, and the other location was for the control section, and a buffer zone having a width of 30 cm was provided between the addition section and the control section. Once all the weeds in the test ground were removed, 1,500 ml of the 0.5% cinnamic acid diluted mixed aqueous solution (cinnamic acid content 7.5 g / m ² ) was sprayed on the addition section to start the test. 1 from the start of the test
On the 4th day, 1,50 again containing 0.5% diluted cinnamic acid diluted aqueous solution
0 ml (cinnamic acid content 7.5 g / m ² ) was sprayed on the addition section.

When the cinnamic acid diluted mixed aqueous solution was sprayed on the addition group, the same amount of water was sprayed on the control group for comparison.
72 days after the start of the test, weeds grown in two test plots were collected, washed with water, and then dried weight (drying conditions are shown in Table 4).
Was measured. The results are shown in Table 4. As shown in Table 4, assuming that the dry weight of weeds in the control group is 1, the dry weight of weeds in the 0.5% cinnamic acid diluted mixed solution addition group is 0.18 to
It is 0.20, and obviously the 0.5% cinnamic acid diluted mixed aqueous solution has a herbicidal effect.

[0047]

[0048]

EFFECTS OF THE INVENTION According to the present invention as described above, there is provided a safe and environmentally friendly weed control agent having a weed control effect as well as an antibacterial and antifungal effect. Further, by using a high-concentration aqueous dispersion or a high-concentration solution as the weed suppressor, it is possible to remarkably improve transport efficiency, storage efficiency and usability.

Claims (7)

[Claims] 1. A non-farmland weed control agent, which comprises cinnamic acid. 2. The non-farmland weed inhibitor according to claim 1, wherein the cinnamic acid is dispersed in an aqueous medium at a high concentration. 3. The non-farmland weed suppressor according to claim 2, wherein the cinnamic acid is dispersed using a dispersant. 4. The non-farmland weed suppressor according to claim 1, wherein the cinnamic acid is dissolved in water with an alkaline solubilizing agent to a concentration exceeding its maximum solubility in water. 5. The weed inhibitor for non-agricultural land according to claim 4, wherein the solubilizing agent is at least one selected from the group consisting of sodium tripolyphosphate, potassium hydroxide and potassium carbonate. 6. The non-farmland weed suppressor according to claim 1, wherein the cinnamic acid concentration is 25% by weight or less. 7. A method for producing a weed suppressor for non-agricultural land, which comprises mixing and dispersing cinnamic acid and an aqueous medium in the presence of a dispersing medium.