JPH08217611A - Agent for reducing crop injury of agrochemical - Google Patents

Abstract

PURPOSE: To obtain an agent for reducing crop injury of agrochemicals, especially injury to the root by using gibberellins which are natural substances produced by plant and known as phytohormones as active components. CONSTITUTION: This agent for reducing crop injury of agrochemicals contains, as active components, gibberellins which are a group of compounds having an ent-gibberane principal skeleton of formula I and belonging to diterpenes. The gibberellins of formula I are preferably selected from gibberellin A1 gibberellin A3 of formula II (gibberellic acid), gibberellin A4 and gibberellin A7 . The agrochemical is preferably a herbicide, a growth-suppressing herbicide or a root-inhibiting herbicide, especially 2-amino-4(α-fluoroethyl)-6-[2-(3',5'- dimethylphenoxy)-1-methylethylamino]-s-triazine, etc. The gibberellin is used in an amount of 1/30 to 10 pts.wt. based on 1 pt.wt. of the agrochemical.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drug capable of reducing phytotoxicity of crops due to agricultural chemicals.

[0002]

BACKGROUND OF THE INVENTION Highly selective herbicides between crops and weeds are
In normal use, weeds can be controlled without damaging the crops, but the crops may be damaged due to various factors such as weather, environment, and misuse. In particular, growth-suppressing (particularly root-inhibiting) herbicides
Chemical damage is likely to occur under excessive water conditions.

Therefore, conventionally, the development of more selective herbicidal agents or the development of phytotoxicity-reducing agents (safeners) for increasing the selectivity of the herbicidal agents has been advanced. Several safeners have been developed for certain herbicides. Examples of those that have been put into practical use include phenchlorim, which is a phytotoxic agent for pretilachlor, which is a chloroacetanilide herbicide, and chlorazole, which is a phytotoxic agent for phenoxaprop-ethyl, which is an allyloxyphenoxy herbicide. . However, these safeners can exert the effect of increasing the selectivity of the herbicide only when used in combination with a specific herbicide, and in combination with other herbicides, the effect cannot be obtained, and are widely and generally used. Not usable.

Further, conventionally known phytotoxicity reducing agents are
There are many chemically synthesized products, which have a large impact on the environment, such as residue in soil. Therefore, in order to reduce the impact on the environment, attempts are currently being made not only in the field of herbicides, but also in reducing the amount of synthetic compounds used and replacing them with natural products.

On the other hand, gibberellin is one of the well-known plant hormones, and various physiological actions on plants are known. For example, actions such as promotion of elongation growth of stems or leaf sheaths, induction of enzyme synthesis, promotion of leaf growth, promotion of germination, promotion of cell division, break of dormancy, promotion of fruit growth, flower bud formation and the like have been clarified to date. The number of compounds classified as gibberellins that have been reported so far has risen to over 70, and it is considered that almost all higher plants have gibberellins.

Although various physiological actions of gibberellins have been reported as described above, reduction of phytotoxicity of crops by herbicides,
In particular, it has not been known about the action of reducing phytotoxicity at the root.

DISCLOSURE OF THE INVENTION The present invention has the action of increasing the selectivity of a pesticide between crops and weeds by applying it together with the pesticide, and reducing the phytotoxicity of the pesticide to useful crops. The first object of the present invention is to provide a compound (pharmaceutical hazard reducing agent) that can be widely used without being limited to the combination with and that has a small effect on the environment.

A second object of the present invention is to provide a method for reducing phytotoxicity of crops using the phytotoxicity reducing agent for the first purpose.

A third object of the present invention is to provide an agrochemical composition containing the phytotoxicity reducing agent of the first object.

[0009]

Under the above circumstances, the inventors of the present invention have intensively searched for a compound that can achieve the first object of the present invention, and as a result, a natural product produced by a plant,
The inventors have found that gibberellins, which are known as plant hormones, have an action of reducing the phytotoxicity of pesticides, particularly the phytotoxicity to roots, and completed the present invention.

That is, the first object is achieved by a phytotoxicity-reducing agent for agricultural chemicals (hereinafter sometimes referred to as "phytotoxicity-reducing agent of the present invention") which contains gibberellins as an active ingredient. It

The above second and third objects are a method for reducing phytotoxicity of agricultural chemicals to crops, which is characterized by using gibberellins (hereinafter sometimes referred to as "the phytotoxicity reducing method of the present invention"), and gibberellin. Each of them is achieved by an agrochemical composition characterized by containing the following compounds (hereinafter sometimes referred to as "agrochemical composition of the present invention").

The present invention will be described in detail below. The gibberellins, which are the active ingredients of the phytotoxicity reducing agent that achieves the first object of the present invention, are natural compounds having various physiological actions on plants, as described above. However, it has not been reported so far that the gibberellins have an action of reducing the phytotoxicity of pesticides, and it is a new physiological action of gibberellins discovered by the present inventors for the first time.

Gibberellins are a kind of diterpenes and have the structural formula

Embedded image Is a group of compounds having a basic skeleton of ent-diberalene represented by

Of these, the most famous one is the mold that causes the stupid seedling disease that led to the discovery of gibberellin.
Gibberellin A produced by Gibberella fujikuroi
₃ (GA ₃ ) (also known as gibberellic acid), with the following structural formula

Embedded image Is a compound represented by.

It is known that gibberellins naturally exist in the free state as well as those bound to glucose. Those bound to glucose include
There are glycoside type and glycosyl ester type as the binding type. Glycoside type gibberellins do not exhibit so-called gibberellin-like activity and are considered to be inactive.

The gibberellins which can be used as a phytotoxicity reducing agent in the present invention include compounds having a basic skeleton of ent-diberalene and exhibiting naturally occurring gibberellin-like activity. Thus, as mentioned above, the free and glycosyl ester type gibberellins are included. Structural formulas of gibberellins used in the present invention are shown in FIGS. Of these, Gibberellin A ₁ ,
A ₃ , A ₄ and A ₇ are preferred, and gibberellin A ₃ is particularly preferred.

The gibberellins, which are the active ingredients of the phytotoxicity-reducing agent of the present invention, may be used alone or in combination of two or more kinds.

The phytotoxicity-reducing agent of the present invention can reduce phytotoxicity to useful crops caused by commonly used agricultural chemicals (agricultural chemicals) such as insecticides, fungicides, herbicides, germination and growth promoters. It is a thing. The phytotoxicity-reducing agent of the present invention can be particularly preferably used for reducing the phytotoxicity of herbicides among agricultural chemicals.

Herbicides control weeds by various mechanisms of action, and the phytotoxicity reducing agent of the present invention is suitable for reducing phytotoxicity caused by growth-suppressing herbicides, particularly root-inhibiting herbicides. Is. The growth-suppressing herbicides include phenoxy-based, benzoic-based, nitrile-based, allyloxyphenoxy-based, carbamate-based, amide-based, chloroacetamide-based, dinitroaniline-based, sulfonylurea-based, imidazolinone-based, sulfate-based, pyridine-based,
It is classified into quinolinecarboxylic acid compounds, cyclohexanedione compounds, triazine compounds and the like. Structural formulas of respective representative examples are shown in FIGS. Among them, those classified as root-inhibiting herbicides include nitriles, dinitroanilines, carbamates, amides, chloroacetanilides, sulfonylureas, imidazolinones, sulphates and triazines. . The phytotoxicity reducing agent of the present invention can be suitably used for reducing phytotoxicity caused by triazine-based and nitrile-based herbicides. In particular, 2-amino-4- (α-fluoro, α-methylethyl) -6- [2- (3 ′, 5 ′, which sometimes exerts a root-inhibiting action on gramineous crops under excessive water conditions and the like.
-Dimethylphenoxy) -1-methyl-ethylamino]
It can be suitably used for reducing the chemical damage caused by -s-triazine (the compound described in Production Example 1 of WO90 / 09378) or diclobenyl (2,6-dichlorocyanobenzene).

The phytotoxicity-reducing agent of the present invention contains gibberellins as an active ingredient, and these compounds are mixed with a liquid carrier such as a solvent or a solid carrier such as a fine mineral powder to prepare a wettable powder or an emulsion. It can be used by formulating it in the form of powder, granules, flowables, liquids and the like. A surfactant may be added in order to impart emulsifying property, dispersibility, spreadability and the like during formulation.

When the phytotoxicity-reducing agent of the present invention is used in the form of a wettable powder, it usually contains 1 to 55% by weight of the active ingredient, gibberellins, 40 to 97% by weight of a solid carrier and 2 to 100% of a surfactant.
The composition may be prepared by blending it in a proportion of 5% by weight and used.

When used in the form of an emulsion, normally 0.5 to 50% by weight of gibberellins, which are active ingredients, and 35 to 9 solvents.
4.5% by weight and surfactants and other auxiliaries 5
It may be prepared by blending it in a proportion of ˜15% by weight.

When used in the form of a dust, it is usually prepared by mixing 0.5 to 15% by weight of the active ingredients, gibberellins, and 85 to 99.5% by weight of a solid carrier.

When used in the form of granules, the active ingredient, gibberellins, 0.01 to 15% by weight, solid carrier 80 to
It may be prepared by mixing 99.99% by weight and 2 to 5% by weight of a surfactant.

When used in the form of a flowable agent, it contains 0.5 to 50% by weight of gibberellins as active ingredients, 35 to 94.5% by weight of water or oil, and 5 to 15% by weight of surfactants and other auxiliary agents. It may be prepared by mixing in a ratio.

When used in the form of a liquid agent, 0.5 to 50% by weight of gibberellins as active ingredients, water and solvent 35
94.5% by weight and surfactants and other auxiliaries 5
It may be prepared by blending at a ratio of 15% by weight.

Here, a fine powder of a mineral substance is used as the solid carrier. Examples of the fine powder of a mineral substance include oxides such as diatomaceous earth and slaked lime, phosphates such as apatite, and sulfates such as gypsum. Examples thereof include talc, pyroferrite, clay, kaolin, bentonite, acid clay, white carbon, silicates such as quartz powder and silica powder.

An organic solvent is used as the solvent,
Specifically, aromatic hydrocarbons such as benzene, toluene and xylene, chlorinated hydrocarbons such as o-chlorotoluene, trichloroethane and trichloroethylene, alcohols such as cyclohexanol, amyl alcohol and ethylene glycol, isophorone, cyclohexanone, cyclohexenyl- Examples thereof include ketones such as cyclohexanone, butyl cellosolve, ethers such as diethyl ether and methyl ethyl ether, esters such as isopropyl acetate, benzyl acetate and methyl phthalate, amides such as dimethylformamide, or a mixture thereof.

Further, as the surfactant, any of anionic type, nonionic type, cationic type and zwitterionic type (amino acid, betaine, etc.) can be used.

The phytotoxicity-reducing agent of the present invention can contain, as an active ingredient, gibberellins and, if necessary, other phytotoxicity-reducing active ingredients. Examples of other phytotoxicity-reducing active ingredients include conventionally known phytotoxicity-reducing agents such as fenchlorim, fenchlorazole, benoxacor, dichloromide, flurazole, fluxofenim, and oxavetrinyl.

Further, the phytotoxicity-reducing agent of the present invention can be mixed with insecticides, fungicides, plant growth regulators, fertilizers and the like other than the drug (agricultural chemicals) component that causes phytotoxicity, if necessary. .

The phytotoxicity reducing method of the present invention which achieves the second object of the present invention reduces the phytotoxicity of agricultural chemicals to crops by using the gibberellins described in detail in the description of the phytotoxicity reducing agent of the present invention. Is the way to do it.

The method of using the gibberellins may be either mixing with the pesticide and simultaneously applying it (mixing simultaneous treatment) or applying it separately from the pesticide (divided treatment).

The form (formulation) of the applied gibberellins is
This is as described in detail in the description of the phytotoxicity reducing agent of the present invention.

There are no particular restrictions on the time of application of the gibberellins, and the gibberellins may be applied to the soil before sowing of the crop, or may be applied when the crop has grown to some extent.

The amount of gibberellins to be used should be appropriately adjusted depending on the type of pesticide used, the application period, etc.
Gibberellins 1/1 for 1 part by weight of conventional pesticides
It is in the range of 100 to 100 parts by weight, preferably 1/30
10 to 10 parts by weight.

The pesticide composition of the present invention which achieves the third object of the present invention comprises both the pesticide compound causing the above-mentioned various phytotoxicity and the gibberellins which are the active ingredients of the phytotoxicity-reducing agent of the present invention. A pesticide containing, that is, a pesticide containing a safener. Gibberellins having a phytotoxicity-reducing action are mixed and formulated with an agrochemical compound that causes phytotoxicity in advance, and are applied at the same time (corresponding to the "mixed simultaneous treatment" described in the description of the phytotoxicity-reducing method of the present invention). As a result, it is possible to reduce the phytotoxicity of the pesticide on useful crops while ensuring the activity of the pesticide.

The pesticide-containing agricultural chemicals of the present invention may contain one kind of agricultural chemical compound as an active ingredient, or may contain two or more kinds.

Further, the agrochemical composition of the present invention may contain other phytotoxicity-reducing agents, insecticides, fungicides, plant growth regulators, fertilizers, etc. other than the agrochemical compounds causing phytotoxicity.

In the agricultural chemicals containing a phytotoxicity-reducing agent of the present invention, the amount of gibberellins to be compounded with respect to 1 part by weight of the agricultural chemicals should be appropriately adjusted depending on the kind of agricultural chemicals to be compounded and the application time.
It is usually in the range of 1/100 to 100 parts by weight, preferably 1/30 to 10 parts by weight.

[0041]

[Examples] The present invention will be specifically described below with reference to formulation examples and examples, but the present invention is not limited thereto.

Gibberellins, which are the active ingredients of the safeners of the present invention used in the formulation examples and examples (indicated by "Compound No. 1" in the formulation examples and examples).
Is the structural formula

Embedded image The herbicide used in Formulation Examples and Examples is gibberellic acid (Gibberellin A ₃ ) (manufactured by Kanto Chemical Co., Inc.)

[Chemical 4] The triazine derivative represented by (in Formulation Examples and Examples,
It is shown as "Compound No. 2". ) And structural formula

Embedded image Is diclovenil (manufactured by Wako Pure Chemical Industries, Ltd.).

The above-mentioned triazine derivative is the compound of International Publication WO
It is a compound described in 90/09378, which is synthesized according to Production Example 1 in the same.

<Formulation Example> 97 parts by weight of clay (trade name: Zyklite, manufactured by Zyklite Industry Co., Ltd.) as a solid carrier, and alkylaryl sulfonate (trade name: Neoperex, manufactured by Kao Atlas Co., Ltd.) as a surfactant 1 .5
Parts by weight and nonionic and anionic surfactants (trade name: Solpol 800A, manufactured by Toho Chemical Industry Co., Ltd.) 1.5
The parts by weight were uniformly pulverized and mixed to obtain a carrier for wettable powder. 90 parts by weight of the obtained wettable powder carrier and Compound No. A wettable powder was obtained by uniformly pulverizing and mixing 10 parts by weight of each of 1, 2 or 3 with each other. In addition, the obtained compound No. A wettable powder containing 1 and a compound No. 1; A wettable powder containing 2 or 3 was uniformly mixed in a predetermined amount (active ingredient ratio) to obtain a wettable powder.

Example 1-Sand Cultivation Pot Test After seeding, barley (cultivar: OTTER) that had grown in the greenhouse for 2 weeks and reached the 2-leaf stage was placed in a pot (surface area: 40 cm ² ) filled with river sand. Three were transplanted each. Next, a predetermined amount of the wettable powder obtained in the above formulation example was suspended in water, and a dropping amount of 10 ml per pot was applied to the entire surface of the pot.
Then, it was grown in a greenhouse and the fresh weight of the root portion was measured 3 weeks after the dropping treatment of the drug. The results are shown in Table 1 below.

[0046]

[Table 1] The numerical values in the table show the ratio of fresh weight to the untreated plot.

From the results shown in Table 1, the herbicide (Compound No. 2
Or the addition of only 3) has a large root inhibition (phytotoxicity) of barley, which is a crop, of 45% and 75%, respectively. It can be seen that, when No. 1) is applied, the phytotoxicity of each compound is greatly reduced.

The application of only gibberellins is 100
It can be seen that even high doses of μg / pot have little adverse effect on crops.

<Example 2> -Soil pot test under super-moisture condition A soil (Arakida soil + river sand, 1: 1) was filled in a Wagner pot of 1/2000 are, and barley seeds (variety: OTTE
R) was seeded at a depth of 0.5 CM. The wettable powder obtained in the above formulation example was suspended in a predetermined amount of water and sprayed uniformly on the entire surface of the pot with a liquid amount of 500 liters / ha. Water was supplied from the bottom of the pot for soil moisture, and it was grown in a greenhouse while maintaining and controlling the saturated moisture content of the soil. The aboveground fresh weight was measured 30 days after the spray treatment of the drug. The results are shown in Table 2 below.

[0050]

[Table 2] The numerical values in the table indicate the fresh weight ratio of the above-ground portion to the untreated area.

From the results shown in Table 2, when the herbicide (Compound No. 2) alone was applied under the excessive water condition where the growth-inhibiting (particularly root-inhibiting) herbicide was liable to cause phytotoxicity, the above-ground inhibition (phytotoxicity) was applied. ) Is as high as 38%, it can be seen that, when gibberellins (Compound No. 1) which is an active ingredient of the phytotoxicity-reducing agent of the present invention is applied together with this herbicide, phytotoxicity is greatly reduced.

[0052]

EFFECTS OF THE INVENTION According to the present invention, the selectivity between crops and weeds of pesticides can be increased, and the phytotoxicity of pesticides to useful crops can be remarkably reduced. Possible safeners have been provided.

The active ingredient gibberellins of the phytotoxicity-reducing agent of the present invention are natural products produced by a wide variety of plants and do not adversely affect the environment.

[Brief description of drawings]

FIG. 1 is a diagram showing the structural formulas of gibberellins that can be used in the present invention.

FIG. 2 is a diagram (continuation from FIG. 1) showing a structural formula of gibberellins that can be used in the present invention.

FIG. 3 is a diagram (continuation from FIG. 1) showing the structural formulas of gibberellins that can be used in the present invention.

FIG. 4 is a diagram (continuation from FIG. 1) showing the structural formula of gibberellins that can be used in the present invention.

FIG. 5 is a diagram (continuation from FIG. 1) showing the structural formula of gibberellins that can be used in the present invention.

FIG. 6 is a diagram (continuation from FIG. 1) showing the structural formula of gibberellins that can be used in the present invention.

FIG. 7 is a diagram (continuation from FIG. 1) showing the structural formulas of gibberellins that can be used in the present invention.

FIG. 8 is a diagram (continuation from FIG. 1) showing the structural formulas of gibberellins that can be used in the present invention.

FIG. 9 is a diagram (continuation from FIG. 1) showing the structural formula of gibberellins that can be used in the present invention.

FIG. 10 is a diagram (continuation from FIG. 1) showing the structural formulas of gibberellins that can be used in the present invention.

FIG. 11 is a diagram showing a structural formula of a typical example of a growth-suppressing herbicide to which the phytotoxicity-reducing agent of the present invention can be applied.

FIG. 12 is a diagram (continuation from FIG. 11) showing a structural formula of a typical example of a growth-inhibiting herbicide to which the phytotoxicity-reducing agent of the present invention can be applied.

FIG. 13 is a diagram (continuation from FIG. 11) showing a structural formula of a typical example of a growth-suppressing herbicide to which the phytotoxicity-reducing agent of the present invention can be applied.

FIG. 14 is a diagram (continuation from FIG. 11) showing a structural formula of a typical example of a growth-suppressing herbicide to which the phytotoxicity-reducing agent of the present invention can be applied.

Claims (11)

[Claims] 1. A phytotoxicity-reducing agent for agricultural chemicals, which comprises gibberellins as an active ingredient. 2. The gibberellins are gibberellin A ₁ (G
A ₁ ), gibberellin A ₃ (GA ₃ ), gibberellin A ₄ (GA
₄ ) and one or more selected from the group consisting of gibberellin A ₇ (GA ₇ ) and the phytotoxicity-reducing agent according to claim 1. 3. The pesticide is a herbicide,
The drug damage reducing agent according to claim 1. 4. The phytotoxicity-reducing agent according to claim 2, wherein the herbicide is a growth-suppressing herbicide. 5. The phytotoxicity-reducing agent according to claim 3, wherein the herbicide is a root-inhibiting herbicide. 6. The phytotoxicity-reducing agent according to claim 5, wherein the herbicide is selected from the group consisting of triazine compounds and nitrile compounds. 7. The herbicide is 2-amino-4- (α-fluoroethyl) -6- [2- (3 ′, 5′-dimethylphenoxy) -1-methyl-ethylamino] -s-triazine or diclobenyl. (2,6-dichlorocyanobenzene), The phytotoxicity reducing agent according to claim 6, which is characterized in that it is (2,6-dichlorocyanobenzene). 8. A method for reducing phytotoxicity of agricultural chemicals to crops, which comprises using gibberellins. 9. Gibberellins / 1 / part by weight of pesticide
The chemical damage reducing method according to claim 8, wherein 100 to 100 parts by weight is used. 10. Gibberellins to 1 part by weight of pesticide.
The phytotoxicity-reducing method according to claim 9, characterized in that / 30 to 10 parts by weight is used. 11. A pesticide composition comprising gibberellins.