JPH01272505A - 2-nitro-5-(substituted pyridyloxy)benzohydroxymic acid derivative herbicide - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention Technical Field The present invention relates to the following formula (1), where R''tli represents a lower alkyl group, kt! represents a hydrogen atom or a lower alkyl group, and R may be substituted. A 2-nitro-5-(substituted pyridyloxy)benzohydroxymic acid derivative represented by an alkenyl group or an optionally alkynyl group, and X represents a hydrogen atom or a halogen atom, respectively. This invention relates to an unveiling agent characterized by containing !-N as an active ingredient.

The benzohydroxymic acid derivative represented by the above formula (1) used in the present invention is a new compound, and has an extremely excellent weeding activity against weeds, and exhibits its effect before and after the germination of weeds and during the growing season. It exhibits the most powerful herbicidal activity, especially during the growth season.

Prior art Japanese Unexamined Patent Application Publication No. 60-226856 discloses that a new diphenyl ether oxime ester derivative having the following general formula (A
), the compound represented by is disclosed.

Here, in the above general formula (A), X/fiCH or N:Y is a nitro group, halogen or cyano group; Z is oxygen or sulfur; R is halogen, nitro group, cyan group
Alkyl group, haloalkyl group, alkylthio group, haloalkylthio group, alkoxy group, haloalkoxy group, sulfonamide group, dialkylsulfonamide group, alkylsulfonyl group, haloalkylsulfonyl group, alkylsulfinyl group or haloalkylsulfinyl group: R'
u Hydrogen, halogen, cyan group, alkyl group, haloalkyl group, cyanoalkyl group, alkoxy group, haloalkoxy group, cyanoalkoxy group, alkylthio group, haloalkylthio group, cyanoalkylthio group, mono- or hasyalkylthio group, alkylthioalkyl group or mono- or dialkylaminoalkyl group: R2 is C□-C8
The alkylene group 19 of is an alkenyl group: it may be substituted with an alkyl group, a haloalkyl group, a cyanoalkyl group or a hydroxyl group; QF
i-OR" or -SR"SR" is an alkoxyalkyl group, thioalkyl group, cyanoalkyl group, cycloalkyl group, hydroxyalkyl group, carboalkoxyalkyl group, alkylthioalkyl group, aralkyl group, sulfonamide group or Fi4 to 6-membered A polycyclic compound of a ring, fc is a group containing 3 or less heteroatoms, and fc is a group containing 3 or less heteroatoms
is an alkyl group substituted with a heterocyclic compound containing up to 3 heteroatoms.

In the above formula (A) compound which can include a very large number of compounds, X includes the occurrence of N, includes the occurrence of RFi halogen and haloalkyl, includes the occurrence of Y#iNO□, R'Fi includes alkoxy, R2 may be alkyl substituted, tAC, alkylene, and 2 includes an oxygen atom. however,
When Q in the formula (A) is -OR'', the definition of R3 is as follows:
An alkenyl group optionally having a substituent b or an alkynyl group optionally having a substituted 2TF' as specified for R in the compound of formula CI) used in the present invention cannot be included. Therefore, as a matter of course, JP-A-60-226856 does not mention the compound of formula (I), its production method, or its herbicidal activity, and does not mention the formula ( There is no suggestion whatsoever regarding the possibility of the existence of the compound I) or any usefulness of the compound of formula (I).

Furthermore, the 4I! ? Publication No. 60-1226856 states,
No specific example is given at all regarding the pseudo compound in which R1 in formula (A) is an alkoxy group or a substituted alkoxy group, and the synthesis thereof. #i is only a methyl group, and preferred examples of R1 include an alkyl group or a haloalkyl group. Moreover, #Unexamined Japanese Patent Publication No. 60-226
Publication No. 856 has a general statement that the compound of formula (A) has herbicidal activity, but there is no specific data that can confirm such herbicidal activity. do not have.

As another proposal, JP-A-56-32432 discloses that a compound represented by the following formula (B) and a compound of the formula (B) have a total herbicidal activity of 1. In the formula (B), X
is NO2, halogen or CN; Y is H or Ficz;
z is CZ when Y is C7, or 2 is when Y is H
or (when l is H, di: R is H and h is C
alkyl up to 1: R1 is H or FicH3 and R2 is H%C□. The alkyl groups up to are agricultural soluble salt ions.

R in the compound of formula (B) specified in this proposal is OR' as specified in the compound of formula (1) used in the present invention.
and R2 in the compound of formula (B) may include all of the R specified in the compound of formula (I). 1972-
No. 32432 also describes the formula CI used in the present invention.
) There is no mention of the compound, its manufacturing method, or its herbicidal activity, nor is there any suggestion of the possibility of the compound of formula (I) or its usefulness. .

Problems to be Solved Currently, a large number of herbicides are being used for agricultural and non-agricultural purposes. Among these many detritivores, foliage treatment type non-selective herbicides are used for railway tracks, industrial sites, etc.
It is placed on non-agricultural land such as parks and vacant lots, or is immediately adsorbed or decomposed in the soil, and is inactivated.9 It takes full advantage of its properties that do not harm the growth of useful plants through the soil, and does not come into contact with the leaves or leaves of useful plants. It is used in agricultural land such as orchards, forest nurseries, and fields using devised processing methods.

In addition, in the United States, which is the world's largest agricultural producer, soil erosion of farmland due to rain and wind has become a major problem. Con5e is a cultivation method that reduces conventional
rvation tillage) or no-till cultivation, in which crops are sown without any tillage (N.

(tillage) method has come into use. However, in the case of no-till cultivation, it is necessary to control weeds that have already occurred before sowing crops.
As the unveiling agent, a foliage Bq type non-selective unveiling agent is used.

Currently, these foliar treatment type non-selective herbicides include U, 1.
1'-dimethyl-4,4'-bipyridylium ion (paracor)), N-(phosphonomethyl)glycine (glyphosate), 2-amino-4-[(hydroxy)(methyl)phosphionyl]butyrylalanylalanine sodium salt (bialaphos), ammonium-(3-amino-
Although 3-carboxypropyl)-methylphosphinate (glufosinate) and the like have been developed or used, their numbers are extremely small, and there are many types of weeds that occur.
In situations where weeds at various growth stages coexist, these existing agents are still insufficient, and there is currently a need for highly effective agents with a broader herbicidal spectrum.

SUMMARY OF THE INVENTION The present inventors have mainly overcome the technical issues of the above-mentioned foliar treatment type non-selective herbicides, and have developed a herbicide that has a low application rate, a wide 19X spectrum, a short soil residual effect, and We have made extensive research efforts to develop a pyridyl phenyl ether herbicide with low toxicity to humans and animals.

As a result, it was found that the compound of formula (I) had superior herbicidal activity kN
It has been discovered that L. is a herbicidal activator that can overcome the technical problems in the prior art described above. Furthermore, the compound of formula (I) was found to be an excellent herbicidal compound exhibiting a broad spectrum of herbicidal activity even at a reduced application rate, and the present invention was further developed.

That is, the present invention provides the following formula (1), where R' represents a lower alkyl group, R2 represents a hydrogen atom or a lower alkyl group, and R#i is a substituted alkenyl group or a substituted The 2-nitro-5-(substituted phenoxy)benzohydroxymic acid derivative represented by the following formula represents an optional alkynyl group, and X represents a hydrogen atom or a halogen atom. The present invention provides a dehydration agent characterized by M.

Effects of the Invention The herbicide containing the pyridylphenyl ether derivative represented by the above general formula m as an effective fraction of the present invention has trifluoromethyl fi'Jk at the 5-position of the pyridine ring, and the ortho-position of the nitro group of the benzene ring. It is characterized by containing a compound to which the hydroxymic acid ester moiety specified in the formula (1) is attached, and due to its structural characteristics, it contains the pyridylphenyl ether derivative of the formula (1). It is thought that the herbicide's Yuku fc properties are exhibited.

The unveiling agent of the present invention is suitable for non-agricultural land, rice, corn,
It has a wide herbicidal spectrum in agricultural fields such as wheat, barley, and soybeans, and is superior in its ability to fully exert its herbicidal activity with a smaller amount of use compared to ordinary herbicides, which cannot be expected from conventional technology. It is a herbicide with unique properties.

DETAILED DESCRIPTION OF THE INVENTION Examples of the halogen atom of X in the pyridylphenyl ether derivative represented by the general formula CI) used in the present invention include fluorine, chlorine, bromine, and iodine. Among these, fluorine and chlorine are preferred.

As the lower alkyl in R1 and R3, carbon Xm
1 to 4 lower alkyl groups are preferred, such as hamethyl, ethyl, n-7'pyl, i-,20pyl, n-butyl,
Examples include S-butyl and i-butyl.

Examples of substituents that R in formula (I) may have include a norogen atom, a C1-C4 alkoxy group, a cyano group, and an alkylthio group having a C, -C4 alkyl group. Examples thereof include an alkoxyΦdicarbonyl group having an alkoxy fi of C, -C, and the like. Examples of the alkenyl group for R include *Cs-04 alkenyl groups such as allyl, metaallyl, and crotyl, and examples of the alkynyl group include C, -C4 alkynyl groups such as propargyl and 2-butynyl. The above formula CI
) is a stereoisomer (syn type).
It is understood that compounds of formula CI) in the form of these isomers are within the scope of the definition of compounds of formula (1) used in the present invention. You should understand.

Among these examples, preferable examples of compounds of formula (I) include those in which R'' is a methyl group, R1 is a hydrogen atom, X is chlorine, or fluorine, and R is substituted with chlorine, particularly C, alkenyl group (-CH2CH=Ci(2)
Alternatively, compounds of C, alkynyl group (-0M2CmiC)I) can be mentioned.

The compound represented by the formula (f) can be produced, for example, by the method shown below.

(II) CI) [In the formula, X, R, R and R are the same as defined above. Y represents a halogen atom. ] As shown above, 0-carboxylic 1,000 ru2
- Reacting the nitro-5-(substituted pyridyloxy)benzohydroxymic acid ester (II) tohalogen compound (III) in, for example, an organic solvent in the presence of a base to produce the above formula (I) compound t-S. I can do it.

According to this embodiment, the reaction is carried out using, for example, 1 to 3 molar equivalents, preferably 1 to 1.5 molar equivalents, of compound (111) relative to compound (II), for example, under water cooling or at the reflux temperature of the solvent. It can be carried out preferably at a temperature between room temperature and around 80 degrees Celsius, for example, under dry conditions for 0.5 to 20 hours.

Examples of solvents used in this warping include aromatic hydrocarbons such as benzene and toluene; ethers such as tetrahydrofuran and dioxane; one or more organic solvents such as acetone, acetonitrile, dimethylformamide, and dimethyl sulfoxide; Examples include mixed solvents of these solvents and water.

Examples of the base used in the above reaction include pyridine, triethylamine, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, and hydrogen carbonate.
Examples include Jium, potassium hydrogen carbonate, and sodium hydride. The amount of the base exemplified above that acts as a dehydrohalogenation agent can be selected as appropriate, but for example, when the compound ([1
), the reaction can be carried out in high yield by using 1 to 3 equivalents, preferably 1 to 1.5 equivalents.

Compounds of formula (I) can also be produced by other embodiments shown below.

OR” (IV) (V) (I) [In the formula, Rj%R'' and R are the same as defined above.

Y is a tl gene or a group -080, R'(R' tlf
tkm, unsubstituted alkyl group, phenyl group, alkoxy group). ] According to this embodiment, 0-[substituted-2-ditro-5-(substituted pyridyloxy)benzhydroxamic acid derivative (IV)
and halide (V)k, for example, in an organic solvent in the presence of a base to form the compound q! of formula (1). lJ gold can be produced.

According to this embodiment, the reaction is performed by adding, for example, 1 to 3 molar equivalents, preferably 1 to 1.0 molar equivalents of compound (V) to compound (IV).
The reaction can be carried out using 5 molar equivalents, for example, under water cooling or at the reflux temperature of the solvent, preferably at room temperature to about 80 degrees Celsius, for example, for 0.5 to 20 hours.

Solvents used in this reaction include, for example, alcohols such as methanol and ethanol; aromatic hydrocarbons such as Hensen and toluene; ethers such as tetrahydrofuran and dioxane; and organic solvents such as acetone, acetonitrile, dimethylformamide, and dimethyl sulfoxide. Examples include one or more solvents and one sweet solvent of these solvents and water.

Examples of the base used in the above reaction include pyridine, triethylamine, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium ethylate, and sodium hydride. By using the dehydrohalogenating agent in an amount of 1 to 3 equivalents, preferably 1 to 1.5 equivalents relative to compound (V), the reaction can be carried out in a t-pot yield.

Moreover, the reaction can be carried out in a two-layer system, and the platform is a quaternary ammonium salt such as tetramethylammonium bromide, tetrabutylammonium bromide, benzyltributylammonium bromide, or a quaternary phosphonium salt such as tetraphenylphosphonium bromide. For example, 1 to 5 QW for phase transfer catalyst gold adducts (V) such as
t4. Preferably, it can be carried out using 5 to 30 Wt4.

Even in the above-mentioned mode, after the reaction is completed, the reaction mixture is poured into water and treated according to conventional methods such as extraction with an organic solvent, recrystallization, column chromatography, etc.
The monster can be isolated.

Next, a specific example of the formula (I) will be described in detail.

Synthesis Example 1 [Methyl O-allyloxycarbonylmethyl 5-(3-chloro-5-) IJ fluoromethyl-
Production of 2-pyridyloxy)-2-nitrobenzohydroxymate (Bakemono 15)] Methyl 〇-carboxymethyl 5-(3-lyrolo-5-) IJ fluoromethyl-2-pyridyloxy)-2- Nitropenzohydroxymate 0.51 (1.11 mmol), Sodium bicarbonate 0.091 (1.11 mmol), DMFl
Allyl bromide 0.271 (2,22
After addition of 1 mmol), stir overnight at room temperature. The reaction mixture was poured into approximately 50-mL ice water, extracted twice with 20-mL ethyl acetate, washed with saturated brine, and dried over magnesium sulfate. After filtering off the desiccant, the solvent was distilled off and the resulting oily substance was subjected to column chromatography (silica gel-n-hexane-
Diluted with ethyl acetate (4:1) to yield 415 tons of the desired compound.
(yield 200-1, yield 36.7%).

Table 1 shows the pyridylphenyl ether derivatives of formula CI) prepared in the same manner as in the sweet acid example above.

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National Engineering = E E Country - Country
ii Industrial Engineering Country Engineering■ Q It exhibits excellent eradication effect at low doses and is useful as a foliage treatment type non-selective herbicide. shows good selectivity for cultivated crops even in foliage treatment,
It can also be an agriculturally useful selective herbicide.

The extermination of the present invention can control various miscellaneous species growing on non-arable land and agricultural land. For example, grasshopper, Japanese grasshopper, Japanese foxtail grass, Japanese grasshopper, Japanese grasshopper, Japanese grasshopper, Japanese barnyard grass, Japanese knotweed, pigweed, silver grass, blackberry, morning glory,
Pigweed, Pigweed, Purslane, Helium japonicum, Pigweed, Episporus, Pygmyus japonica, Deer oxalis, Oxalis, Datura japonica, Chickweed, Chickweed, Chickweed,
Shepherd's purse, Tanetsukebana, Yaemugura, Hobby, Chamomile, Ezono foxtail, Marigold, Hotokenoza,
It can control terrestrial narrow-leaved and broad-leaved pests such as dog puffer, Japanese violet, Japanese mugwort, and cypress. Furthermore, it can also control aquatic narrow-leaved and mucus-leafed graves such as Japanese wild grass, Japanese cypress, Japanese cypress, Japanese azalea, Japanese chickweed, Japanese chickweed, bulrush, Japanese cypress, and so on.

The herbicide of the present invention is used not only on non-agricultural land but also on
Even in agricultural land where useful plants are planted, the whole surface is treated before the useful plants germinate, and the treatment method is devised to prevent the chemicals from coming into contact with the leaves and stems of the useful plants during the post-germination growth period ([)i
It can be used with reCl 5pray). Furthermore, it is useful for agriculture that if the uninvented herbicide is used at a lower dose than the dose of the active ingredient that exhibits non-selective activity, it will be effective against cultivated crops even in whole-foliage treatments. It exhibits high selectivity and controls various miscellaneous species, and does not cause phytotoxicity that is a practical problem, especially for legume crops such as rice, corn, wheat, barley, turgid, sugarcane, etc., and broad-leaved crops such as dice and sunflowers. It can be used without any restrictions.

The compound of formula (I) is actually used as a herbicide.
k@- can be combined with carriers or diluents, additives, auxiliaries, etc. using known methods to form formulations that are commonly used as agricultural chemicals, such as powders, granules, water-containing agents, emulsions, and aqueous preparations. Used as a backside for solvents, sol agents, etc. It can also be used alone or in combination with other II&drugs, such as fungicides, insecticides, acaricides, herbicides, plant prenatal regulators, fertilizers, soil conditioners, etc.

Especially when used in combination with other herbicides, the use system t'
In addition to reducing energy consumption and saving labor, it is also expected that the synergistic action of both drugs will expand the power collection spectrum and produce even greater effects due to their synergistic action.

The carrier or #i diluent may be used for general VC convenience.
Solid or liquid carriers can be used. Solid carriers include clays and talc, such as kaolinite group, montmorillonite group, and attapulgium group; mica;
Jadeite, pumice, vermiculite, gypsum, calcium carbonate, dolomite, diatomite, magnesium lime,
Inorganic substances such as apatite, zeolite, anhydrous silicic acid, and basal calcium silicate; Vegetable organic substances such as soybean flour, tobacco powder, walnut flour, wheat flour, wood flour, starch, and crystalline cellulose; Coumaron resin, petroleum resin , alkyd resins, polyvinyl chloride, polyalkylene glycols, ketone resins, ester gums, copal gums, dammar gums, and other synthetic or natural polymer compounds; waxes such as carnauba wax and beeswax; and urea.

Suitable liquid carriers include paraffinic or naphthenic hydrocarbons such as kerosene, mineral oil, spindle oil, white oil; aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, cumene, methylnaphthalene;
Chlorinated hydrocarbons such as carbon tetrachloride, chloroform, trichloroethylene, monochlorobenzene, 0-chlorotoluene; More ethers such as dioxane and tetrahydro7rane; Ketones such as acetone, methyl ethyl ketone, diisobutyl ketone, cyclohexanone, acetophenone, isophorone, etc. ; Esters such as ethyl acetate, amyl acetate, ethylene glycol acetate, diethylene glycol acetate, diptyl maleate, diethyl succinate:
methanol, n-hexanol, ethylene glycol,
Alcohols such as diethylene glycol, cyclohexanol, and benzyl alcohol: Ether alcohols such as ethylene glycol ethyl ether, ethylene glycol phenyl ether, diethylene glycol ethyl ether, and diethylene glycol butyl ether; Polar solvents such as dimethylformamide and dimethyl sulfoxide; and water, etc. Ran.

In addition, emulsification, dispersion, and wetting of the compound of formula (1),
Surfactants and other auxiliary agents may also be used for purposes such as spreading, binding, disintegration, stabilizing active ingredients, improving fluidity, and preventing rust. Examples of surfactants used are:
Although non-ionic, anionic, cationic and zwitterionic compounds can be used, it is preferred that non-ionic and/or ionic compounds be used. Examples of suitable nonionic surfactants include those obtained by polymerizing and adding ethylene oxide to higher alcohols such as lauryl alcohol, stearyl alcohol, and oleyl alcohol; those obtained by polymerizing and adding ethylene oxide to alkylphenols such as isooctylphenol and nonylphenol; nibutyl; Those obtained by polymerizing and adding ethylene oxide to alkylnaphthols such as naphthol and octylnaphthol; those obtained by polymerizing and adding ethylene oxide to higher fatty acids such as palmitic acid, stearic acid, and oleic acid;
Polymerized addition of ethylene oxide to monomodal alkyl phosphoric acid such as stearyl phosphoric acid and dilauryl phosphoric acid. Products obtained by polymerization and addition of ethylene oxide to amines such as nidodecylamine and stearic acid amide: Higher fatty acids of polyhydric alcohols such as sorbitan. Examples include esters and those obtained by adding ethylene oxide to them in N-substance; and those obtained by adding ethylene oxide and propylene oxide by complete polymerization. Suitable anionic surfactants include, for example, alkyl sulfate ester salts such as sodium lauryl sulfate and oleyl alcohol sulfate amine salt; alkyl sulfonic acids such as sodium sulfokoacid dioctyl ester and sodium 2-ethylhexene sulfonate; Salts: Examples include arylsulfonates such as sodium isoprobylnaphthalenesulfonate, sodium methylenebisnaphthalenesulfonate, sodium ligninsulfonate, and sodium dodecylbenzenesulfonate.

In addition, the herbicide of the present invention may contain polymerized substances such as casein, gelatin, albumin, glue, sodium alginate, carboxymethyl cellulose, methyl cellulose, hydroxyethyl cellulose, polyvinyl alcohol, etc., in order to improve the properties of the preparation and increase the herbicidal effect. 7. The carriers and various adjuvants mentioned above can be used alone or in combination depending on the purpose, taking into account the dosage form of the preparation, the application situation, etc. It can be used as appropriate.

Each of the compounds of the present invention @ heavy punishment obtained in this way may contain the active ingredient of the formula (I) in the formulation, although it varies depending on the layer formulation, for example, 0. 1-99 weight i
14, preferably 11 to 80 weight.

Powder formulations usually contain, for example, 1 to 25 active ingredients, with the remainder being a solid carrier.

Wettable powders usually contain, for example, 25 to 90% by weight of the active ingredient, with the remainder being a solid carrier and a dispersing wetting agent. ! Insurance colloid agent, chicken trope agent, according to '4C,
Antifoaming agents etc. are added.

Granules, for example, usually contain 1 to 35% of the active ingredient, and the remainder is mostly solid carrier.

The active ingredient Fi is uniformly mixed with the solid carrier, or is uniformly fixed or adsorbed on the surface of the solid carrier, and the particle size is about 0.2 to 1.5 parts. It is.

For example, the emulsion is usually made of an effective bottom differentiated product with a weight of 1 to 30%.
This solution contains about 5 to 2031% emulsifier, the remainder is liquid carrier, and rust preventive agent is added as needed.

The 2-ditro-5-(substituted pyridyloxy)benzohydroxymic acid derivative herbicide of the present invention obtained as described above may be used as an adduct of general formula (1) or as an optional compound as described above. It can be applied in the form of preparation.

The herbicide of the present invention can be applied to various weeds growing in non-agricultural land and agricultural land from before emergence to the growing season, and it is particularly suitable to apply to various weeds during the growing season. The application time t should be selected depending on whether a small amount of application is sufficient as the static neutralizing activity of the compound of the formula (I) is extremely high IA, or depending on the type of target coarse leather, growth stage, application location, application time, weather, etc. Can be changed. 0.01 to 10,000 f per 1 ha as the compound '1i (N active ingredient t) represented by the general formula (1)
degree, preferably 0.1 to 5ooop8 degrees.

More preferably, the non-selective herbicide is lhaha
It is about 0 to 20,009 per lha, and as a selective herbicide, it is about lha per v1 to 50f. First, we will show the roughness of an example of a backing agent for an fc herbicide using the compound of the general formula CI). The scale in the formulation examples below is based on weight.

Example 1 (granules) Kakemono 41 5 parts bentonite 50 parts Merck
40 parts Sodium dodecylbenzenesulfonate 2 parts Sodium ligninsulfonate
2 parts polyoxyethylene alkylaryl ether After mixing with 1 part or more of gold, add an appropriate amount of water, knead, and granulate in a granulator to make 100% granules.
I got the department.

Example 2 (Irrigation agent) 1 Sweets A1
2ON5 Keink±
60 parts white carbon 1
5 parts sodium lignin sulfonate 3 parts sodium dotecylbenzenesulfonate 2 parts or more were mixed together and uniformly ground by a kneader to obtain 100 parts of an aqueous phase agent.

Example 3 (emulsion) Compound &15 30 evil xylene
55 parts cyclohexanone
10 parts calcium dodecylbenzenesulfonate 3 parts polyoxyethylene alkyl allyl ether 2 or more parts were mixed uniformly to form emulsion 1.
I got 00 copies.

Test Example 1 (Stem and leaf treatment) A square pot (aoxaoxsm) was filled with field soil, and a certain number of various weed seeds shown in Table 2 were borrowed, and 27 days after sowing when each plant was in the 3-6 leaf stage. It was grown in a greenhouse until then.

For the chemical treatment, an emulsion of the desiccating agent of the present invention was prepared in the same manner as in Formulation Example 3, and the amount of the active ingredient was as shown in Table 2! Sea urchin, as a spreading agent [Surfactant WKJ'i 0.25'
The mixture was diluted with a water pressure of 16% and uniformly sprayed on the leaves and foliage with an amount of water equivalent to 500 At/ha.

21 days after the chemical spraying, the effect of unveiling on each miscellaneous vehicle was judged according to the following criteria, and the results are shown in Table 2I/c.
Indicated.

Evaluation criteria (11 levels) Table 2 Test example 2 of foliage treatment effect (soil mixing treatment = safety for crops in crop preplanting treatment) Preparation according to test example 1, dilution with water, and predetermined amount of the unveiling agent of the present invention. Field soil was sprayed at a water rate of 500 J/ha and filled into square pots after thorough mixing, and various crops shown in Table 3 were sown at a depth of lcMl, and the soil was placed in the front bottom in a greenhouse.

On the 21st day after sowing, the degree of chemical damage to each crop was measured in Test Example 1.
The results are shown in Table 3.

Table 3 Soil treatment effect test example 3 (Study of foliage treatment at low dosage = crop selectivity) Square pots (30X30X9c!t1) were filled with upland soil treatment, and various crops and miscellaneous seeds shown in Table 4 were added. A fixed amount of mushrooms were sown, and the mushrooms were grown in a greenhouse 18 days after sowing when each plant was at the 1.5-3 leaf stage.

For the chemical treatment, a predetermined amount of the unveiling agent of the present invention shown in Table 4 was adjusted and sprayed according to Test Example 1.

On the 21st day after the chemical treatment, the unveiling effect on each crop and the degree of chemical damage to each crop were evaluated according to the criteria of Test Example 1, and the results are shown in Table 4.

Claims (1)

[Claims] (1) The following formula (I), ▲Mathematical formula, chemical formula, table, etc.▼...(I) However, in the formula, R^1 represents a lower alkyl group, and R^2 represents a hydrogen atom or a lower alkyl group. 2-nitro-5-(substituted pyridyloxy) represented by
A herbicide characterized by containing a benzohydroxymic acid derivative as an active ingredient.