JPH068242B2 - Improved paddy herbicide composition - Google Patents

Description

TECHNICAL FIELD The present invention comprises a sulfonylurea derivative useful for controlling perennial weeds that are difficult to control agriculturally, and a herbicide for millet weeds that is sparingly soluble in water. The present invention relates to an improved herbicide granule composition for paddy fields.

(Prior Art) Many sulfonylurea derivatives are already known as herbicides, and have excellent effects on perennial weeds which are difficult to control. (For example, U.S. Pat. No. 4,127,405,
4169719, JP-A-57-112379, 59.
-31775).

Further, it is known that a labor-saving herbicide having a broad herbicidal spectrum can be obtained by mixing this sulfonylurea derivative and a herbicide for grass family weeds to form a composite preparation (for example, JP-A-58). 188803, 59-
82306).

(Problems to be Solved by the Invention) Such a characteristic composite granule comprising two kinds of herbicides is particularly convenient for spraying as a paddy herbicide, and its development is desired. However, when these two kinds of herbicides are formulated into granules by a conventional technique, there is a problem that the sulfonylurea derivative decomposes with time when the product is stored for a long period of time. In addition, many herbicides for grass weeds are insoluble or sparingly soluble in water, and when used as a composite granule, a sufficient effect cannot be expected.

As a technique for stabilizing the herbicidal component in the herbicidal granule, a method of adding various stabilizers has been conventionally used (for example, Japanese Patent Publication No.
-28398, 45-28399, 46-3071
No. 7, 47-24129, 47-37008), a method of physically isolating a herbicidal component from a substance that promotes decomposition (for example, Japanese Examined Patent Publication No. 52-21059), and a compound using a water-soluble inorganic salt or the like. A method for obtaining the stabilized aqueous composition of (for example, JP-A-59-205305) is known.

With the composite granules of the present invention, a sufficient stabilizing effect cannot be obtained by the method of adding these stabilizers, and by adding them depending on the kind of the stabilizers, secondary stabilizers such as environmental pollution after spraying the granules can be obtained. There is a concern that it will cause various problems. Further, the method of coating the active ingredient with a wax-like substance suppresses the release of the active ingredient into water and reduces the herbicidal effect. Furthermore, in the method for obtaining a stabilized aqueous composition of a compound using a water-soluble inorganic salt or the like, the sulfonylurea derivative becomes a water-soluble salt in the aqueous composition and is stabilized, but since the water solubility increases, the sulfonylurea derivative is rapidly dissolved in the granule. However, the chemical damage derived from this compound is further enhanced by the release of the compound.

On the other hand, when the present composite granules are prepared by conventional known techniques and applied to the paddy field, the herbicidal effect of the sulfonylurea derivative is sufficiently expressed, but the herbicidal effect of the fly by the sparingly water-soluble herbaceous weed herbicide is There is a problem of decrease.

This is because when a sulfonylurea derivative is treated in paddy water, it quickly dissolves in water and is absorbed by roots and foliage of susceptible plants such as annual broad-leaved weeds and Cyperaceae weeds, and inhibits cell division at extremely low concentrations. However, these susceptible plants are killed in a short period of time, but the sulfonylurea derivatives do not kill them because they have low susceptibility to the grass millet weeds. It is also for lowering.
During the period until the sulfonylurea derivative absorbed in the body of the weed is metabolized to an inactive substance and disappears and the absorption function of the drug is restored, runoff due to water leakage and falling water, etc., which occurs after the application of the herbicide for the grass family Weed, It is considered that this is due to the loss from the paddy water due to adsorption to the soil, transpiration from the paddy water, uptake by other plants, etc., and an insufficient amount of the drug to sufficiently kill the weeds.

Therefore, the herbicide for millet weeds is preferentially used as a granule for exhibiting the herbicidal effect of the herbicide for millet weeds, which is poorly soluble in water, and for stably obtaining the herbicidal effect of the sulfonylurea derivative. It is necessary to release the sulfonylurea derivative into the tap water and release it after a certain period of time, preferably 2 to 5 days.

Even if the trace amount of the sulfonylurea derivative is gradually released into water, a sufficient herbicidal effect is not obtained, and thus it is desirable that the sulfonylurea derivative is rapidly released into the paddy water after a certain period of time in the present combined preparation.

As a technique relating to this, conventionally, various auxiliaries have been used to accelerate the disintegration property of granules and accelerate the elution of components (for example, Japanese Examined Patent Publication Nos. 40-25520 and 48-38858,
52-47016, 53-46888), or conversely, as a technique for suppressing the elution of components, a method of suppressing the disintegration of particles (for example, Japanese Examined Patent Publication No. 45-2200), and suppressing the release of components by coating with a resin. Method (for example, Japanese Patent Publication No. Sho 41-19
No. 080) is known. All of these techniques are aimed at promoting the rapid release of the components in the granules immediately after spraying or gradually releasing the components in minute amounts over a long period of time. The purpose is either to promote or to suppress.

On the other hand, in the composite granules of the present invention, it is necessary to complete the technique of promoting the release of one component and suppressing the release of the sulfonylurea derivative on the other hand for a certain period, and then rapidly releasing it. It is not possible to obtain such controlled release complex herbicides.

The present inventors stabilized a sulfonylurea derivative which is easily decomposed in granules, and quickly released a sparingly soluble herbicide for millet weeds in water in the granules after spraying into the paddy water, while
The sulfonylurea derivative is preferably 2 to after a certain period of time.
Studies were repeated with the aim of completing a formulation that released rapidly after 5 days.

As a result, by blending calcium carbonate and one or more of sodium pyrophosphate, potassium pyrophosphate or sodium tripolyphosphate in the granule, the sulfonylurea derivative is stabilized, and after spraying, it is sparingly soluble in water from the granule. The present invention was completed by finding that the herbicide for millet weeds is preferentially released in the above and the sulfonylurea derivative is rapidly released after a certain period.

(Means for Solving the Problems) The herbicidal composition of the present invention comprises (A) the general formula [I]. (However, in the formula, X is , Y represents CH or N, R ¹ represents a methyl group or a methoxy group, R ² represents a chlorine atom, a methyl group or a methoxy group, and R ³ represents a chlorine atom, a bromine atom, a nitro group, a lower alkyl group. group, a lower alkoxy group, the formula _-CO 2 ^{R 6,} wherein _-SO 2 ^{R 6,} or the formula And R ⁴ , R ⁵ , R ⁶ and R ⁷ represent a hydrogen atom or a lower alkyl group. ), S- (4-chlorobenzyl) N, N-diethylthiocarbamate, S-benzyl N- (1,2-dimethylpropyl) -N-ethylthiocarbamate, S-
(1-Methyl-1-phenylethyl) piperidine-1-
Carbothioate, 2- (1,3-benzothiazole-
2-yloxy) -N-methylacetanilide or 3,
A compound selected from 7-dichloroquinoline-8-carboxylic acid, (C) calcium carbonate and (D) sodium tripolyphosphate, sodium pyrophosphate or potassium pyrophosphate, and one or more kinds thereof (provided that
S- (4-chlorobenzyl) N, N-diethylthiocarbamate and 2-[(4,6-dimethylpyrimidine-2
-Yl) Aminocarbonylaminosulfonylmethyl] benzoic acid methyl ester in combination is not included. ) Is included.

Examples of the sulfonylurea derivative include the following compounds.

Compound 1 Compound 2 Compound 3 Compound 4 Compound 5 Compound 6 Compound 7 Compound 8 The sulfonylurea derivative is not limited to these, and compounds represented by the general formula (1) can be widely applied.

On the other hand, examples of herbicides for grass weeds include the following.

Compound A (Solubility in water 30ppm / 20 ℃) Compound B (Solubility in water 30ppm / 20 ℃) Compound C (water solubility 32ppm / 20 ° C) Compound D (solubility in water 4ppm / 20 ° C) Compound E (water solubility 64ppm / 20 ° C) In order to produce the granules of the present invention, the herbicidal ingredient is mixed with calcium carbonate, condensed phosphates and, if necessary, additives such as a bulking agent and a surfactant, and the mixture is mixed with water, followed by extrusion molding. , One of the herbicidal ingredients is mixed with calcium carbonate, a condensed phosphate and additives such as a bulking agent and a surfactant, if necessary, and mixed with water, and after extrusion molding, other herbicidal ingredients are added thereto. Examples include a method of spray-adsorbing, a method of spray-coating river sand with a herbicidal component, and then adding fine powder of calcium carbonate, condensed phosphate and an auxiliary agent to the surface to adhere to the surface of river sand. I can, but
It is not limited to these methods.

The blending ratio of calcium carbonate and condensed phosphate used in the present invention is not particularly limited, but with respect to the composition,
By weight, calcium carbonate is preferably 10 to 90% by weight and condensed phosphate is 1 to 10% by weight.

In the granules of the present invention, alkylbenzene sulfonate, lignin sulfonate, which is an auxiliary agent of granules that are usually used,
Alkyl sulfosuccinate, naphthalene sulfonate,
Polyoxyethylene alkyl aryl ether sulfate,
Surfactants such as polyoxyethylene alkylaryl ethers, polyoxyethylene alkyl ethers, polyoxyethylene fatty acid alkyl esters, alkylamine salts, bentonite, clay, talc, diatomaceous earth, synthetic hydrous silicic acid, fillers such as river sand, starch, CMC, sizing agents such as polyvinyl alcohol, xylene, kerosene, methylnaphthalene, methylene chloride, isopropyl alcohol, ethylene glycol, ethyl cellosolve, cyclohexanone, dimethylformamide, acetonitrile, liquid paraffin, etc., stabilizers such as inorganic and organic acids, and Inorganic salts and the like can be used as necessary.

The sulfonylurea derivative in the granule of the present invention is stabilized,
Moreover, the mechanism for controlling the elution of the active ingredient from the granules sprayed on the paddy field is not clear, but the following may be considered.

The sulfonylurea derivative is more alkaline than acidic and stable, and the addition of the condensed phosphate makes the metal and the like contained in the extender inactive and further improves the stability of the active ingredient.

The sulfonylurea derivative is alkaline and forms a kind of salt with calcium and sodium ions, but the calcium salt has a lower solubility in water than the sodium salt. In the present invention, the temporary sulfonylurea derivative has a reduced water solubility due to the calcium carbonate used, but after the granules disintegrate and disperse in water, the sulfonylurea derivative is affected again by the corrosive organic matter in the soil, clay minerals, etc. The solubility of the derivative is increased.

By compounding the condensed phosphate into the granule, the disintegration and dispersion of the granule in water is remarkably improved. Therefore, the dissolution rate in water of a compound that is sparingly soluble in water and excellent for the millet family weeds is further improved. improves.

Condensed phosphates have the action of improving the rate of absorption of compounds that are sparingly soluble in water and exhibit excellent effects on grass flies weeds.

Next, examples will be described.

(Example) Example 1 0.5 part of the compound (3), 10 parts of powdered calcium carbonate, and 10 parts of sodium tripolyphosphate are mixed and ground with a hammer mill to obtain fine powder.

Quartz sand (silver sand) 72.5 sized to 14-32 mesh
And 7 parts of the compound (B) were mixed, and after confirming that the surface of the quartz sand (silica sand) was uniformly wet, the fine powder 20.5
The parts were added little by little and mixed, and uniformly adhered to the surface of quartz sand (silica sand) to obtain the herbicidal granules of the present invention.

Example 2 0.07 part of compound (6), 18 parts of powdered calcium carbonate,
Mix 1 part potassium pyrophosphate and 2.93 parts talc,
Grind with a hammer mill to make a fine powder.

Granular calcium carbonate 72 sized to 14-32 mesh
And 7 parts of the compound (A) were mixed, and it was confirmed that the surface of the granular calcium carbonate was uniformly wet.
The parts were added little by little and mixed, and uniformly adhered to the surface of the granular calcium carbonate to obtain the herbicidal granule of the present invention.

Example 3 0.75 parts of compound (5), 30 parts of powdered calcium carbonate,
Sodium tripolyphosphate 5 parts, bentonite 30 parts,
After mixing 22.25 parts of talc, 2 parts of sodium alkylbenzene sulfonate and 3 parts of polyvinyl alcohol, pulverize with a hammer mill to obtain fine powder.

Appropriate water is added to this, and the mixture is kneaded, extruded from a screen having a diameter of 1 mm, dried at 80 ° C., and sieved with a 14 to 32 mesh to obtain granules.

7 parts of the compound (A) was spray-adsorbed on 93 parts of the granules to obtain the herbicide of the present invention.

Example 4 0.25 parts of compound (2), 4 parts of compound (D), 60 parts of calcium carbonate powder, 3 parts of sodium pyrophosphate, 27.75 parts of bentonite, 2 parts of sodium alkylbenzenesulfonate, 3 parts of sodium ligninsulfonate. After mixing, pulverize with a hammer mill to obtain fine powder.

Appropriate water was added to this, and the mixture was kneaded, extruded from a screen having a diameter of 1 mm, dried at 80 ° C., and sieved with a 14 to 32 mesh to obtain the herbicide of the present invention.

Example 5 0.15 parts of compound (7), 10 parts of compound (C), 50 parts of powdered calcium carbonate, 8 parts of potassium pyrophosphate, 21.85 parts of bentonite, 5 parts of white carbon, 2 parts of sodium alkylbenzene sulfonate, lignin After mixing 3 parts of sodium sulfonate, pulverize with a hammer mill to obtain fine powder.

Appropriate water was added to this, and the mixture was kneaded, extruded from a screen having a diameter of 1 mm, dried at 80 ° C., and sieved with a 14 to 32 mesh to obtain the herbicide of the present invention.

Example 6 0.35 parts of compound (8), 1.3 parts of compound (E), 60 parts of powdered calcium carbonate, sodium tripolyphosphate 3
Parts, potassium pyrophosphate 3 parts, bentonite 27.35
Parts, 2 parts of sodium alkylbenzene sulfonate, and 3 parts of sodium lignin sulfonate are mixed, and then ground with a hammer mill to obtain fine powder.

Appropriate water was added to this, and the mixture was kneaded, extruded from a screen having a diameter of 1 mm, dried at 80 ° C., and selectively used with 1 to 32 mesh to obtain the herbicide of the present invention.

Comparative Example 1 Compound (3) 0.5 part, sodium tripolyphosphate 10
Parts and 10 parts of talc are mixed and ground with a hammer mill to obtain fine powder.

Quartz sand (silver sand) 72.5 sized to 14-32 mesh
And 7 parts of the compound (B) were mixed, and after confirming that the surface of the quartz sand (silica sand) was uniformly wet, the fine powder 20.5
The parts were added little by little and mixed, and uniformly adhered to the surface of quartz sand (silica sand) to obtain a herbicidal granule.

Comparative Example 2 Compound (6) 0.07 part, powdered calcium carbonate 18 parts,
2.93 parts of talc are mixed and ground with a hammer mill to give a fine powder.

Granular calcium carbonate 72 sized to 14-32 mesh
And 7 parts of the compound (A) were mixed, and it was confirmed that the surface of the granular calcium carbonate was uniformly wet.
The parts were added little by little and mixed, and uniformly adhered to the surface of the granular calcium carbonate to obtain a herbicide.

Comparative Example 3 0.75 parts of compound (5), 30 parts of powdered calcium carbonate,
30 parts of bentonite, 27.25 parts of talc, 2 parts of sodium alkylbenzenesulfonate and 3 parts of polyvinyl alcohol are mixed and then pulverized with a hammer mill to obtain fine powder. Appropriate water is added to this, and the mixture is kneaded, extruded from a screen having a diameter of 1 mm, dried at 80 ° C., and sieved with a 14 to 32 mesh to obtain granules.

7 parts of the compound (A) was spray-adsorbed on 93 parts of this granular material to obtain a herbicide.

Comparative Example 4 0.25 parts of compound (2), 4 parts of compound (D), 3 parts of sodium pyrophosphate, 27.75 parts of bentonite, 60 parts of clay, 2 parts of sodium alkylbenzenesulfonate,
After mixing 3 parts of sodium ligninsulfonate, it is ground with a hammer mill to obtain a fine powder.

Appropriate water was added to this, and the mixture was kneaded, extruded from a screen having a diameter of 1 mm, dried at 80 ° C., and sieved with a 14 to 32 mesh to obtain a herbicide.

Comparative Example 5 0.5 part of the compound (3), 2 parts of white carbon and 18.5 parts of clay are mixed and pulverized with a hammer mill to obtain fine powder.

After mixing 72 parts of quartz sand (silica sand) sized to 14 to 32 mesh with 7 parts of compound (B) and confirming that the surface of the quartz sand (silica sand) was wet, 21 parts of fine powder was added little by little. While mixing, the herbicidal granules were obtained by uniformly adhering to the surface of quartz sand (silica sand).

Comparative Example 6 0.07 parts of compound (6), 7 parts of compound (A), N.I. N-
It is dissolved in 2.93 parts of dimethylformamide and spray-adsorbed to 90 parts of attapulgite whose particle size is adjusted to 14 to 32 mesh in a rotary mixer. After the spraying of the solution was completed, the mixture was mixed for a while to obtain a herbicide granule.

Comparative Example 7 0.75 parts of compound (5), 5 parts of white carbon, 17 parts of bentonite, 70.25 parts of calcium carbonate, 2 parts of sodium alkylbenzene sulfonate, 3 parts of polyvinyl alcohol were mixed and then pulverized with a hammer mill to give a fine powder. Use as powder.

Appropriate water was added to this, and the mixture was kneaded, extruded from a screen having a diameter of 1 mm, dried at 80 ° C., and sieved with a 14 to 32 mesh to obtain granules.

7 parts of the compound (A) was spray-adsorbed on 93 parts of this granular material to obtain a herbicide.

Comparative Example 8 0.35 parts of compound (8), 1.3 parts of compound (E), 3 parts of potassium pyrophosphate, 28 parts of bentonite, clay 6
2.35 parts, 3 parts of sodium lignin sulfonate and 2 parts of sodium alkylbenzene sulfonate are mixed and then pulverized with a hammer mill to obtain fine powder.

Appropriate water was added to this, and the mixture was kneaded, extruded from a screen having a diameter of 1 mm, dried at 80 ° C., and sieved with a 14 to 32 mesh to obtain a herbicide.

Comparative Example 9 Compound (C) 10 parts, bentonite 40 parts, clay 35
Parts, 2 parts of sodium alkylbenzene sulfonate and 3 parts of polyvinyl alcohol are mixed and pulverized with a hammer mill to obtain fine powder.

Appropriate water is added to this fine powder, and the mixture is kneaded, extruded through a screen having a diameter of 1 mm, dried at 60 ° C., and sieved with a 16 to 32 mesh to obtain granules.

90 parts of this granular material is heated to 90 ° C. Separately 0.15 parts of compound (7) and paraffin wax (145 ° F) 9
Parts, sorbitan monostearate 0.85 parts, and
The crushed product in a mortar was uniformly mixed with the heated granules, cooled, and sieved with 14 mesh to obtain a herbicide.

Comparative Example 10 1.11 parts of sodium ligninsulfonate and 4.48 parts of sodium hydroxide were dissolved in 54.35 parts of water, and 21.3 parts of the compound (2) was added little by little while stirring to cause water reaction. The sodium salt was formed. To this solution was added 4.68 parts of sodium acetate and after 5 minutes another 4.6
8 parts were added. After observing that precipitation of the sodium salt of the compound (2) occurred rapidly after about 15 minutes, 9.35 parts of sodium acetate was further added. The resulting composition was ground with a sand mill to produce particles with a particle size of 5 microns or less. The polysaccharide thickener was added minutes before the grinding operation was completed.

Sodium salt suspension of this compound (2) (component content 2
1.1%) 1.2 parts, compound (D) 4 parts, sodium lignin sulfonate 3 parts, sodium alkylbenzene sulfonate 2 parts, bentonite 40 parts, clay 50.75
Parts are added and mixed, and crushed by a hammer mill to obtain a fine powder.

Appropriate water was added to this, and the mixture was kneaded, extruded from a screen having a diameter of 1 mm, dried at 60 ° C., and sieved with a 14 to 32 mesh to obtain a herbicide.

The effects of the present invention are shown below.

(Effects of the Invention) The herbicidal granules of the present invention have good stability of herbicidal components and, at the same time, sufficiently exhibit the properties of the herbicidal components, and thus exhibit a broad herbicidal spectrum against weeds.

In addition, the composition of the present invention has the effect of reducing the phytotoxicity of paddy rice because the dissolution of the sulfonylurea derivative into the paddy water is delayed.

Test Example 1 Stability Test The herbicide granule was sealed in a glass bottle and stored in a thermostat at 50 ° C. for a predetermined period. After the abuse treatment, the herbicidal granules were taken out and the content of the sulfonylurea derivative in each herbicide was measured by high performance liquid chromatography, and the content of other compounds was measured by high performance liquid chromatography or gas chromatography. The decomposition rate was calculated from the change in the content rate of the compound before and after the abuse treatment.

The results are shown in Table 2.

Test Example 2 Dissolution test of active ingredients in water 3 at 1 / 5000a Wagner pot in a thermostatic chamber at 20 ° C.
800 ml of hard water was added and left still. About 80 mg of each weighed herbicide accurately weighed (corresponding to 4 kg of granule per 10 a) was charged therein.

1 day, 3 days, and 5 days after the addition, add water from the center of each pot.
Collect with a 0 ml whole pipette. After extraction with chloroform, it was concentrated with a rotary evaporator, the sulfonylurea derivative was obtained by high performance liquid chromatography and the other compounds were obtained by high performance liquid chromatography or gas chromatography to calculate the content, and the concentration in water was calculated from that value, and eluted in water. From the amount of each compound (μg) and the amount of each compound contained in the added granules (μg), the dissolution rate in water was determined by the following formula.

The results are shown in Table 3.

Test Example 3 Medicinal Effect / Pharmaceutical Damage Test <Medicinal Effect Test> In a greenhouse, a 1 / 5000a Wagner pot was filled with paddy soil, and after water entry, fertilization, and soil scraping, seeds of Tainubie were sown on the soil surface layer. In another pot, 6 tubers of Spodoptera litura were buried in water so that buds would emerge. The water depth was 3 cm.

The leaf age of Tainubie is 2 and the leaf of Cyperus japonicus is 2
At about 15 cm), 15 strains of Tainubie and 3 strains of Spodoptera frugiperda were prepared per pot, and a predetermined amount of each herbicide granule (equivalent to spraying 1.5 kg of granule per 10 a) was weighed and sprayed in 3 consecutive times.

30 days after the chemical treatment, the dry weight of the above-ground portion was measured and compared with that of the non-treated section.

<Drug damage test> In a greenhouse, 1 / 5000a Wagner pots were filled with paddy soil, and after water entry, fertilization, and scraping, transplanted seedlings (cultivar: Kinnanfeng leaf age: 2 leaves), 3 strains per plant, 1 plantation It was transplanted to a depth of 2 cm and submerged to a depth of 3 cm.

Two days after transplantation, the prescribed amount of each herbicide granule (6 kg of granule per 10a)
(Corresponding to spraying) was weighed and sprayed in three consecutive times. The leaf age at the time of treatment was 2.2 to 2.3 leaves.

30 days after the chemical treatment, the dry weight of the above-ground portion was measured and compared with that of the non-treated section.

The untreated area was completely weeded by hand to avoid weed damage.

The results of the drug efficacy / damage test are shown in Table 4.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location (A01N 47/36 47:18) (A01N 47/36 43:42) (A01N 47/36 43: 78)

Claims (1)

[Claims] 1. (A) General formula [I] (However, in the formula, X is , Y represents CH or N, R ¹ represents a methyl group or a methoxy group, R ² represents a chlorine atom, a methyl group or a methoxy group, and R ³ represents a chlorine atom, a bromine atom, a nitro group, a lower alkyl group. group, a lower alkoxy group, the formula _-CO 2 ^{R 6,} wherein _-SO 2 ^{R 6,} or the formula And R ⁴ , R ⁵ , R ⁶ and R ⁷ represent a hydrogen atom or a lower alkyl group. ), S- (4-chlorobenzyl) N, N-diethylthiocarbamate, S-benzyl N- (1,2-dimethylpropyl) -N-ethylthiocarbamate, S-
(1-Methyl-1-phenylethyl) piperidine-1-
Carbothioate, 2- (1,3-benzothiazole-
2-yloxy) -N-methylacetanilide or 3,
A compound selected from 7-dichloroquinoline-8-carboxylic acid, (C) calcium carbonate and (D) sodium tripolyphosphate, sodium pyrophosphate or potassium pyrophosphate, and one or more kinds thereof (provided that
S- (4-chlorobenzyl) N, N-diethylthiocarbamate and 2-[(4,6-dimethylpyrimidine-2
-Yl) Aminocarbonylaminosulfonylmethyl] benzoic acid methyl ester in combination is not included. And an improved herbicide composition for paddy fields.