# Patent

## Title
Herbicide composition for paddy field

## Abstract

A herbicide composition for paddy field characterized by containing (a) a herbicidal difluoromethanesulfonamide derivative represented by the formula (I)




and (b) at least one herbicidal compound selected from the group consisting of pretilachlor, butachlor, alachlor, metolachlor, acetochlor, clomeprop, bromobutide, benfuresate, indanofan, pyrazolate, benzofenap, pyrazoxyfen, pyraclonil, oxaziclomefone, bensulfuron-methyl, azimsulfuron, imazosulfuron, pyrazosulfuron-ethyl, cyclosulfamuron, ethoxysulfuron, halosulfuron-methyl, orthosulfamuron, cinosulfuron, metsulfuron-methyl, penoxsulam, thiobencarb, pyributycarb, molinate, dimethametryn, simetryn, cafenstrole, quinclorac, anilofos, mefenacet, fentrazamide, pentoxazone, oxadiargyl, oxadiazon, benzobicyclon, mesotrione, AVH301 (code no.), cyhalofop-butyl, metamifop, bispyribac-sodium, pyriftalid, pyrimisulfan, pyrimenobac-methyl, chlormethoxynil, oxyfluorfen, dithiopyr, MCPA, MCPB, 2,4-D, dymron, cumyluron, quinoclamine and clomazone, and/or (c) one or more compounds selected from the group consisting of safeners dymron, isoxadifen(-ethyl), flurazole, fenchlorazole-ethyl, fenclorim, cloquintocet-mexyl, oxabetrinil, fluxofenim, mefenpyr-diethyl, furilazole, R-29148 (code no.), benoxacor, dichlormid and dicyclonone as effective components.

## Background
INCORPORATION BY REFERENCE
This application claims benefit under 35 U.S.C. 119(a) of Japanese patent application 2006-6422, filed on 13 Jan. 2006.
Any foregoing applications, including Japanese patent application 2006-6422, and all documents cited therein or during their prosecution (“application cited documents”) and all documents cited or referenced in the application cited documents, and all documents cited or referenced herein (“herein cited documents”), and all documents cited or referenced in herein cited documents, together with any manufacturer's instructions, descriptions, product specifications, and product sheets for any products mentioned herein or in any document incorporated by reference herein, are hereby incorporated herein by reference, and may be employed in the practice of the invention.
The present invention relates to a herbicide composition for a paddy field. More specifically the present invention relates to a herbicide composition for a paddy field containing a herbicidal difluoromethanesulfonamide derivative and a certain kind of known herbicidal compound as effective components.
Difluoromethanesulfonamide (DFMS) derivatives represented by the formula




wherein

    X represents a halogen,
    Y represents CH or N,
    R1 represents hydrogen, and
    R2 represents hydrogen or hydroxy, or
    R1 and R2 together may form C═O with the carbon atom to which they are bonding, are known compounds (WO-A-2005/096818). Some of these derivatives show good controlling effect against paddy field weeds. However, contrary to expectation, some DFMS compounds do not show a fully satisfactory herbicidal effect and phytotoxicity to paddy rice is observed. In practical usage, it is difficult to provide a single active compound with such properties as to correspond to various kinds of usage, as there are many potential elements influencing the herbicidal effect. Examples of such elements include the kinds of weeds to be controlled, the conditions of their developing area, etc., and as such the effect of an active compound is different. In addition, with regard to considerations of cost reduction in agricultural production, effects on the environment, etc., development of an agent showing effective action with less application amount is also a desired goal.


The invention does not intend to encompass within the scope of the invention any previously disclosed product, process of making the product or method of using the product, which meets the written description and enablement requirements of the USPTO (35 U.S.C. 112, first paragraph) or the EPO (Article 83 of the EPC), such that applicant(s) reserve the right and hereby disclose a disclaimer of any previously described product, method of making the product or process of using the product.
It is noted that in this disclosure and particularly in the claims and/or paragraphs, terms such as “comprises”, “comprised”, “comprising” and the like can have the meaning attributed to it in U.S. Patent law; e.g., they can mean “includes”, “included”, “including”, and the like; and that terms such as “consisting essentially of” and “consists essentially of” have the meaning ascribed to them in U.S. Patent law, e.g., they allow for elements not explicitly recited, but exclude elements that are found in the prior art or that affect a basic or novel characteristic of the invention.
These and other embodiments are disclosed or are apparent from and encompassed by, the following Detailed Description.
In order to fulfill the desired goal(s), one of the methods to improve properties of a herbicide is to mix it with other active compounds. However, the expected effect of such mixtures is not necessarily obtained due to factors such as decomposition of active compounds, antagonistic action of effects, etc.
The present inventors have found that the composition mentioned below shows an excellent and desirable effect in terms of weed controlling in paddy field and lowering phytotoxicity to rice.
Thus, the present invention provides a herbicide composition for a paddy field comprising a combination of components (a), (b) and/or (c), wherein

    
    
        (a) is one or more difluoromethanesulfonamide derivative compounds represented by the formula
    
    






wherein

    X represents a halogen,
    Y represents CH or N,
    R1 represents hydrogen, and
    R2 represents hydrogen or hydroxy, or
    R1 and R2 together may form C═O with the carbon atom to which they are bonding,
    
        (b) is one or more herbicidal compounds selected from the group consisting of pretilachlor, butachlor, alachlor, metolachlor, acetochlor, clomeprop, bromobutide, benfuresate, indanofan, pyrazolate, benzofenap, pyrazoxyfen, pyraclonil, oxaziclomefone, bensulfuron-methyl, azimsulfuron, imazosulfuron, pyrazosulfuron-ethyl, cyclosulfamuron, ethoxysulfuron, halosulfuron-methyl, orthosulfamuron, cinosulfuron, metsulfuron-methyl, penoxsulam, thiobencarb, pyributycarb, molinate, dimethametryn, simetryn, cafenstrole, quinclorac, anilofos, mefenacet, fentrazamide, pentoxazone, oxadiargyl, oxadiazon, benzobicyclon, mesotrione, AVH301 (code no.), cyhalofop-butyl, metamifop, bispyribac-sodium, pyriftalid, pyrimisulfan, pyrimenobac-methyl, chlormethoxynil (chlomethoxyfen), oxyfluorfen, dithiopyr, MCPA, MCPB, 2,4-D, dymron, cumyluron, quinoclamine and clomazone, and
        (c) is one or more safener compounds selected from the group consisting of dymron, isoxadifen(-ethyl), flurazole, fenchlorazole-ethyl, fenclorim, cloquintocet-mexyl, oxabetrinil, fluxofenim, mefenpyr-diethyl, furilazole, R-29148 (code no.), benoxacor, dichlormid and dicyclonone as effective components.
    
    


In the following the compounds of components (a), (b) and (c) are also named compounds (a), (b) or (c), respectively. The components (a), (b) and (c) are also shortly named compound (a), (b) or (c) respectively.
Surprisingly, the composition of the present invention, provides a substantially higher herbicidal effect (synergistic effect) than the sum of the effect of each active compound applied individually. As a result, for controlling weeds, it is possible to substantially reduce the concentration of each compound as used previously in the art. At the same time for the composition of the invention, a broad herbicidal spectrum can be obtained and the application period can be increased. In the paddy rice culture, for example, the compositions of the invention show excellent herbicidal effect when applied any time from the early stage of weed development just after the transplantation to growing period. In addition, the effects are maintained for a long period Thus, an excellent herbicidal effect with an excellent residual effect and no phytotoxicity to rice is obtained.
In one embodiment of the invention, the compound (a) of the formula (I) in the composition of the present invention, is defined as a compound of formula (I) wherein:

    X represents fluorine or chlorine,
    Y represents CH or N,
    R1 represents hydrogen, and
    R2 represents hydrogen or hydroxy, or
    R1 and R2 together may form C═O with the carbon atom to which they are bonding.


In another embodiment of the invention examples of the compound (a) of the formula (I) in the composition of the present invention can be those mentioned in the Table A mentioned below:











TABLE A





Compound No.
X
Y
R1
R2



















1
F
CH
H
OH


2
F
N
H
OH


3
Cl
CH
H
OH


4
Cl
N
H
OH


5
Br
CH
H
OH


6
Br
N
H
OH


7
I
CH
H
OH


8
I
N
H
OH


9
F
CH
H
H


10
F
N
H
H


11
Cl
CH
H
H


12
Cl
N
H
H


13
Br
CH
H
H


14
Br
N
H
H


15
I
CH
H
H


16
I
N
H
H











17
F
CH
C═O



18
F
N
C═O


19
Cl
CH
C═O


20
Br
CH
C═O


21
Br
N
C═O


22
I
CH
C═O


23
I
N
C═O









These compounds can be used individually or in combination of two or more.
In the composition of the present invention, the herbicidal compounds (b) used in combination with the compound (a) of the above-mentioned formula (I) are as aforementioned, and in one embodiment of the invention, examples can be (b-1) anilofos, (b-2) pretilachlor, (b-3) cafenstrole, (b-4) cyhalofop-butyl, (b-5) penoxsulam, (b-6) pyraclonil, (b-7) bispyribac-sodium, (b-8) fentrazamide, (b-9) mefenacet, (b-10) oxaziclomefone, (b-11) benfuresate, (b-12) bensulfuron-methyl, (b-13) ethoxysulfuron, (b-14) bromobutide and (b-15) AVH301.
The above-mentioned herbicidal compounds (b) can be used, individually or in combination of two or more, as a mixture with a compound (a) of the formula (I).
The compounds (c) as safener used in combination with the compound (a) of the above-mentioned formula (I) according to the present invention are as aforementioned, and in one embodiment of the invention examples can be (c-1) dymron, (c-2) mefenpyr-diethyl, (c-3) isoxadifen and (c-4) isoxadifen-ethyl.
The above-mentioned compounds (c) as safener can be used, individually or in combination of two kinds or more, as a mixture with a compound (a) of the formula (I).
The above-mentioned herbicidal compounds (b) and the compounds (c) as safener are described in, for example, The Pesticide Manual, 13th edition (published by British Crop Protection Council, 2003) or “Compendium of Pesticide Common Names” (http://www.alanwood.net/pesticides). The compound having the code number AVH 301 is a herbicide having the chemical name 2-{2-chloro-4-mesyl-3-[(tetrahydrofuran-2-ylmethoxy)-methyl]-benzoyl}-cyclohexan-1,3-dione, also known under the common name “tefuryltrione”. The compound having the code number R-29148 is a safener having the chemical name 3-(dichloroacetyl)-2,2,5-trimethyl-oxazolidine known from DE-A-02350800 (U.S. Pat. No. 3,989,503).
In the composition of the present invention, the mixing ratio of a compound (a) of the formula (I) and a herbicidal compound (b) can be varied in a relatively wide range according to the kind, application period, application place, application method, etc. of said composition. Generally, at least one herbicidal compounds (b) in the range of 0.05-200 parts by weight, (in another embodiment of the invention, 0.1-100 parts by weight) can be used to 1 part by weight of a compound (a) of the formula (I). Specifically, in one embodiment of the invention for individual usage ratio of herbicidal compounds (b) to 1 part by weight of a compound (a) of the formula (I) there can be mentioned the following embodiments.

    Anilofos (b-1): 0.5-50 parts by weight, or 1-20 parts by weight,
    Pretilachlor (b-2): 0.5-50 parts by weight, or 1-20 parts by weight,
    Cafenstrole (b-3): 0.5-50 parts by weight, or 1-20 parts by weight,
    Cyhalofop-butyl (b-4): 0.3-30 parts by weight, or 0.5-10 parts by weight,
    Penoxsulam (b-5): 0.2-10 parts by weight, or 1-5 parts by weight,
    Pyraclonil (b-6): 0.5-50 parts by weight, or 1-20 parts by weight,
    Bispyribac-sodium (b-7): 0.1-10 parts by weight, or 0.2-5 parts by weight,
    Fentrazamide (b-8): 0.5-50 parts by weight, or 1-20 parts by weight,
    Mefenacet (b-9): 2-200 parts by weight, or 5-50 parts by weight,
    Oxaziclomefone (b-10): 0.2-10 parts by weight, or 1-5 parts by weight,
    Benfuresate (b-11): 0.5-50 parts by weight, or 1-20 parts by weight,
    Bensulfuron-methyl (b-12): 0.1-10 parts by weight, or 0.2-5 parts by weight,
    Ethoxysulfuron (b-13): 0.1-10 parts by weight, or 0.2-5 parts by weight,
    Bromobutide (b-14): 2-200 parts by weight, or 5-50 parts by weight,
    AVH301 (b-15): 0.5-50 parts by weight, or 1-30 parts by weight.


In the composition of the present invention, the mixing ratio of a compound (a) of the formula (I) and a compound (c) as safener can be varied in a relatively wide range according to the kind, application period, application place, application method, etc. of said composition. Generally, at least one compounds (c) as safener in the range of 0.05-200 parts by weight, (in another embodiment of the invention 0.2-100 parts by weight) can be used to 1 part by weight of a compound (a) of the formula (I). Specifically, in one embodiment of the invention for individual usage ratio of compounds (c) to 1 part by weight of a compound (a) of the formula (I) there can be mentioned the following.

    Dymron (c-1): 0.5-100 parts by weight, or 1-20 parts by weight,
    Mefenpyr-diethyl (c-2): 0.05-10 parts by weight, or 0.5-5 parts by weight,
    Isoxadifen (c-3): 0.05-10 parts by weight, or 0.5-5 parts by weight, Isoxadifen-ethyl
    (c-4): 0.05-10 parts by weight, or 0.5-5 parts by weight.


The composition of the present invention shows a strong controlling effect against paddy field weeds and therefore said composition can be used as a herbicide composition for paddy field, particularly a selective herbicide for paddy rice.
An object of the invention is thus the use of a combination of herbicide (a) and herbicide (b) or safener (c) or a combination of components (a)+(b)+(c) for controlling weeds in a paddy field, optionally in the presence of a crop of useful plants, particularly rice plants. The components can be applied to the paddy field and its weed plants in sequential manner or simultaneously. Another object of the invention is thus the method wherein the components (a), (b) and/or (c) are applied accordingly.
The composition of the present invention can be used against various kinds of weeds developing in the paddy field. As their examples there can be mentioned the following:
Dicotyledonous plants of the following Genera: Polygonum, Rorippa, Rotala, Lindernia, Bidens, Dopatrium, Eclipta, Elatine, Gratiola, Lindernia, Ludwigia, Oenanthe, Ranunculus, Deinostema, etc.
Monocotyledonous plants of the following Genera: Echinochloa, Panicum, Poa, Cyperus, Monochoria, Fimbristylis, Sagittaria, Eleocharis, Scirpus, Alisma, Aneilema, Blyxa, Eriocaulon, Potamogeton, etc.
The composition of the present invention can be used, more specifically for example, in relation to the following typical paddy field weeds.
Dicotyledonous Plants


    Rotala indica Koehne
    Lindernia procumbens Philcox
    Ludwigia prostrata Roxburgh
    Potamogeton distinctus A. Benn
    Elatine triandra Schk
    Oenanthe javanica 

Monocotyledonous Plants

    Echinochloa oryzicola Vasing
    Monochoria vaginalis Presl
    Eleocharis acicularis L.
    Eleocharis Kuroguwai Ohwi
    Cyperus difformis L.
    Cyperus serotinus Rottboel
    Sagittaria pygmaea Miq
    Alisma canaliculatum A. Br. et Bouche
    Scirpus juncoides Roxburgh


The use of the composition of the present invention, however, should not be restricted to these weeds in any way, but can be applied against other weeds in the same manner.
The composition of the present invention can be made into customary formulation forms for control of paddy field weeds. As such formulation forms there can be mentioned, for example, solutions, emulsions, wettable powders, suspensions, powders, soluble powders, granules, suspo-emulsion concentrates, solid formulations (jumbo formulations), floating granules, microcapsules in polymer substance, etc.
These formulations can be prepared according to per se known methods. The formulations according to the present invention can be prepared, for example, by mixing the aforementioned compound (a) of the formula (I), herbicidal compound (b) and/or compound (c) with extenders, namely liquid diluents and/or solid diluents, and, in case of necessity, by using surfactants, namely emulsifiers and/or dispersants and/or foam-forming agents.
In case of using water as extender, for example, organic solvents can be used as auxiliary solvent. As liquid diluents there can be mentioned, for example, organic solvents such as aromatic hydrocarbons (for example, xylene, toluene, alkylnaphthalene, etc.), chlorinated aromatic or chlorinated aliphatic hydrocarbons (for example, chlorobenzenes, ethylene chlorides, methylene chloride, etc.), aliphatic hydrocarbons (for example, cyclohexane etc. or paraffins (for example, mineral oil fractions, mineral oils, vegetable oils, etc.)), alcohols (for example, butanol, glycols, etc. and their ethers, esters, etc.) ketones (for example, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), strongly polar solvents (for example, dimethylformamide, dimethyl sulfoxide, etc.), and water.
As solid diluents there can be mentioned, for example, ammonium salts, ground natural minerals (for example, kaolin, clay, talc, chalk, quartz, attapulgite, montmorillonite, diatomaceous earth, etc.), ground synthetic minerals (for example, highly dispersed silicic acid, alumina, silicates, etc.) etc. As solid carriers for powders there can be used, for example, crushed and fractionated rocks (for example, calcite, marble, pumice, sepiolite, dolomite, etc.) synthetic granules of inorganic and organic meals, particles of organic materials (for example, saw dust, coconut shells, maize cobs, tobacco stalks, etc.) etc.
As emulsifiers and/or foaming agents there can be mentioned nonionic or anionic emulsifiers (for example, polyoxyethylene fatty acid esters, polyoxyethylene fatty alcohol ethers (for example, alkylaryl polyglycol ethers, alkylsulfonates, alkylsulfates, arylsulfonates, etc.)), albumin hydrolysis products, etc.
As dispersants, for example, lignin sulfite waste liquor, methyl cellulose, etc. are adequate.
Tackifiers can also be used in formulations (powders, granules, emulsifiable concentrates). As said tackifiers there can be mentioned, for example, carboxymethyl cellulose, natural and synthetic polymers (for example, gum Arabic, polyvinyl alcohol, polyvinyl acetates, etc.) natural phospholipids (for example, cephalins or recithins), synthetic phospholipids, etc. Further, as additives, mineral oils and vegetable oils can be used.
Colorants can also be used. As said colorants there can be mentioned inorganic pigments (for example, iron oxide, titanium oxide, Prussian Blue, etc,), organic dyestuffs such as alizarin dyestuffs, azo dyestuffs or metal phthalocyanine dyestuffs, and further traces nutrients such as salts of iron, manganese, boron, copper, cobalt, molybdenum or zinc.
The formulations can contain the total of the compound of the formula (I) (a), herbicidal compound (b) and/or compound (c) at a concentration in the range of generally 0.1-95% by weight (in another embodiment of the invention 0.5-90% by weight).
The composition of the present invention can be used for controlling weeds as themselves or in their formulation forms. It is also possible to do tank mixing at the time of application and further to contain other known active compounds, particularly active compounds generally used in the paddy field, for example, fungicides, insecticides, plant growth regulators, plant nutrients, soil improving agents, etc.
The composition of the present invention can be used as such or in their formulation forms or in application forms prepared by further diluting said formulations, for example, in the forms of ready-to-use solutions, emulsifiable concentrates, suspensions, powders, wettable powders or granules. Formulations of these forms can be applied to paddy field by usual methods, for example, watering, spraying, atomizing, dusting, granule spreading, etc.
The composition of the present invention can be applied to the paddy field before, at the time and after the transplantation. The amount of said composition to be applied can be varied in a substantial range. The amount can be in the range of, for example, 0.01-5 kg/ha (in another embodiment of the invention 0.06-4.5 kg/ha) as the total amount of the compound of the formula (I) (a), herbicidal compound (b) and/or compound (c).
The invention is further described by the following non-limiting examples which further illustrate the invention, and are not intended, nor should they be interpreted to, limit the scope of the invention.


BIOLOGICAL TEST EXAMPLES AND FORMULATION EXAMPLES
Test Compounds


    Component (a) (a-1): compound No. 1 (ref: the aforementioned Table A)
     (a-2): compound No. 3 (same as above)
     (a-3): compound No. 11 (same as above)
    Component (b) the aforementioned (b-1)-(b-15)
    Component (c) the aforementioned (c-1)-(c-3)

<Preparation of Test Agents>

    Carrier: Acetone 5 parts by weight
    Surfactant: Benzyloxy polyglycol ether 1 part by weight

The above-mentioned carrier and surfactant and 1 part by weight of active compounds (component (a) and component (b) or component (c)) are mixed and the obtained formulations are diluted with water to prepare the test agents of the prescribed chemicals amount (preparations).



Test Example 1
Test of Effect of the Herbicide Composition Against Paddy Field Weeds
<Test Method>
In a green house, seeds or tubers of Monochoria vaginalis Presl, annual broad-leaves (Lindernia procumbens Philcox, Rotala indica Koehne, Elatine triandra Schk, Ammannia multiflora Roxb., etc.), Cyperus serotinus Rottboel, and Sagittaria pygmaea Miq were inoculated to paddy field soil filled in a 500 cm2 pot and brought to a submerged condition of about 2-3 cm. At 1.5-2 leafstage of each weed prescribed diluted solution of preparation of each active compound and each herbicide in the following table was applied on water surface each singly or simultaneously. After the treatment, the submerged condition of 3 cm was maintained and the herbicidal effect was studied 3 weeks after the treatment. The herbicidal effect was evaluated as 100% in case of complete death and 0% in case of no effect.
<Results>
Results are shown in Table 1-Table 3. In the tables, MOOVP represents Monochoria vaginalis Presl, BBBBB represents annual broad-leaves, CYPSE represents Cyperus serotinus Rottboel and SAGPY represents Sagittaria pygmaea Miq.









TABLE 1








Amount of



Active
effective
Herbicidal effect (%)












component
component g/ha
MOOVP
BBBBB
CYPSE
SAGPY


(a-1)
2.5
40
70
80
60















+(b-1)
+200
90
100
90
70



+100
70
80
80
70


Single
200
10
0
0
10



100
10
0
0
10


+(b-2)
+250
100
100
80
90



+125
70
90
80
80


Single
250
20
10
0
10



125
10
10
0
0


+(b-3)
+150
100
100
100
90



+75
90
100
80
70


Single
150
60
50
70
10



75
50
40
0
10


+(b-4)
+180
50
70
80
70



+90
40
70
70
60


Single
180
10
0
0
20



90
0
0
0
10


+(b-5)
+100
90
90
100
80



+50
80
90
100
80


Single
100
90
90
70
85



50
75
50
70
65


+(b-6)
+100
90
100
100
90



+50
90
100
100
80


Single
100
90
90
30
85



50
80
90
20
50


+(b-7)
+5
70
90
100
80



+2.5
40
80
90
80


Single
5
10
10
60
30



2.5
0
10
20
0


+(b-8)
+150
100
100
100
90



+75
90
85
100
80


Single
150
60
70
30
30



75
40
40
30
30


+(b-9)
+600
100
90
100
80



+300
100
90
80
70


Single
600
80
40
30
10



300
65
30
30
10


+(b-10)
+40
80
90
100
80



+20
60
70
70
60


Single
40
20
40
0
10



20
10
40
0
0


+(b-11)
+250
70
90
100
80



+125
60
80
100
50


Single
250
0
0
70
20



125
0
0
20
10


+(b-12)
+5
70
100
100
95



+2.5
50
90
100
80


Single
5
60
60
40
50



2.5
30
50
40
50


+(b-13)
+3
85
100
100
90



+1.5
80
85
90
75


Single
3
70
70
0
65



1.5
65
40
0
65


+(b-14)
+400
90
80
90
70



+200
70
50
85
70


Single
400
95
30
60
10



200
30
20
40
10


+(b-15)
+150
100
90
90
80



+75
100
80
80
80


Single
150
95
65
85
80



75
85
50
80
80


















TABLE 2








Amount of



Active
effective
Herbicidal effect (%)












component
component g/ha
MOOVP
BBBBB
CYPSE
SAGPY


(a-2)
2.5
30
60
75
60















+(b-1)
+200
90
100
90
70



+100
60
70
70
60


Single
200
10
0
0
10



100
10
0
0
10


+(b-2)
+250
95
95
70
90



+125
80
85
40
70


Single
250
20
10
0
10



125
10
10
0
0


+(b-3)
+150
100
100
100
85



+75
90
90
70
80


Single
150
60
50
70
10



75
50
40
0
10


+(b-4)
+180
60
70
95
80



+90
50
70
70
80


Single
180
10
0
0
20



90
0
0
0
10


+(b-5)
+100
85
95
100
80



+50
85
90
95
70


Single
100
90
90
70
85



50
75
50
70
65


+(b-6)
+100
95
100
100
85



+50
90
100
70
80


Single
100
90
90
30
85



50
80
90
20
50


+(b-7)
+5
60
85
100
80



+2.5
40
60
90
80


Single
5
10
10
60
30



2.5
0
10
20
0


+(b-8)
+150
100
100
100
85



+75
90
85
95
85


Single
150
60
70
30
30



75
40
40
30
30


+(b-9)
+600
100
90
100
70



+300
90
85
70
70


Single
600
80
40
30
10



300
65
30
30
10


+(b-10)
+40
70
80
95
80



+20
40
60
70
70


Single
40
20
40
0
10



20
10
40
0
0


+(b-11)
+250
80
90
100
70



+125
50
60
80
50


Single
250
0
0
70
20



125
0
0
20
10


+(b-12)
+5
85
90
100
70



+2.5
50
80
100
70


Single
5
60
60
40
50



2.5
30
50
40
50


+(b-13)
+3
85
80
100
80



+1.5
80
80
80
75


Single
3
70
70
0
65



1.5
65
40
0
65


+(b-14)
+400
90
70
90
80



+200
40
50
90
60


Single
400
95
30
60
10



200
30
20
40
10


+(b-15)
+150
90
85
90
80



+75
100
70
80
85


Single
150
95
65
85
80



75
85
50
80
80


















TABLE 3








Amount of



Active
effective
Herbicidal effect (%)












component
component g/ha
MOOVP
BBBBB
CYPSE
SAGPY


(a-3)
5.0
30
60
50
50















+(b-1)
+200
70
80
90
70



+100
50
50
70
60


Single
200
10
0
0
10



100
10
0
0
10


+(b-2)
+250
70
80
60
70



+125
50
75
40
60


Single
250
20
10
0
10



125
10
10
0
0


+(b-3)
+150
90
90
100
70



+75
90
85
60
60


Single
150
60
50
70
10



75
50
40
0
10


+(b-4)
+180
50
60
80
70



+90
30
60
60
70


Single
180
10
0
0
20



90
0
0
0
10


+(b-5)
+100
80
95
90
90



+50
85
90
80
70


Single
100
90
90
70
85



50
75
50
70
65


+(b-6)
+100
100
100
80
100



+50
90
100
70
80


Single
100
90
90
30
85



50
80
90
20
50


+(b-7)
+5
50
80
100
80



+2.5
30
75
80
70


Single
5
10
10
60
30



2.5
0
10
20
0


+(b-8)
+150
90
90
80
80



+75
60
85
80
80


Single
150
60
70
30
30



75
40
40
30
30


+(b-9)
+600
90
90
90
70



+300
80
85
80
60


Single
600
80
40
30
10



300
65
30
30
10


+(b-10)
+40
70
80
80
70



+20
50
70
70
70


Single
40
20
40
0
10



20
10
40
0
0


+(b-11)
+250
50
60
90
70



+125
40
60
70
70


Single
250
0
0
70
20



125
0
0
20
10


+(b-12)
+5
80
95
90
85



+2.5
40
90
90
70


Single
5
60
60
40
50



2.5
30
50
40
50


+(b-13)
+3
80
90
70
80



+1.5
80
90
50
80


Single
3
70
70
0
65



+1.5
65
40
0
65


+(b-14)
+400
90
80
90
80



+200
60
60
70
70


Single
400
95
30
60
10



200
30
20
40
10


+(b-15)
+150
90
100
90
90



+75
90
80
70
85


Single
150
95
65
85
80



75
85
50
80
80









Test Example 2
Test of Effect of Phytotoxicity Reduction
<Test Method>
In a green house, paddy rice of 2-2.5 leafstage was transplanted to paddy field soil filled in a 1000 cm2 pot to 2 cm depth and brought to a submerged condition of about 2-3 cm. Five days after the transplantation, prescribed diluted solution of preparation of each active compound and each herbicide in the following table was applied on water surface each singly or simultaneously. After the treatment, the submerged condition of 3 cm was maintained and the grade of phytotoxicity to paddy rice was studied 2 weeks after the treatment. The phytotoxicity was evaluated as 100% in case of complete death and 0% in case of no phytotoxicity.
<Results>
Results are shown in Table 4.











TABLE 4








Amount of effective




Active
component



component
(g/ha)
Phytotoxicity %




















(a-1)
120
50




 60
30



+(c-1)
120 + 450
30




 60 + 450
20



+(c-2)
120 + 500
30




 60 + 500
20



+(c-3)
120 + 500
45




 60 + 500
20



(a-2)
120
40




 60
20



+(c-1)
120 + 450
25




 60 + 450
10



+(c-2)
120 + 500
25




 60 + 500
10



+(c-3)
120 + 500
35




 60 + 500
10



(a-3)
180
30




 90
20



+(c-1)
180 + 450
10




 90 + 450
0



+(c-2)
180 + 500
20




 90 + 500
10



+(c-3)
180 + 500
25




 90 + 500
10



(c-1)
450
0



(c-2)
500
0



(c-3)
500
0










Formulation Example 1
To a mixture of 3 parts by weight of the active compound (a-1), 4 parts by weight of the active compound (b-1), 32 parts by weight of bentonite (montmorillonite), 58 parts by weight of talc and 3 parts by weight of ligninsulfonate salt, 25 parts by weight of water were added, well kneaded, made into granules of 10-40 mesh by an extrusion granulator and dried at 40-50° C. to obtain granules.
Formulation Example 2
96 Parts by weight of clay mineral particles having particle diameter distribution in the range of 0.2-2 mm are put in a rotary mixer. While rotating it, 2 parts by weight of the active compound (a-1) and 2 parts by weight of the active compound (b-2) are sprayed together with a liquid diluent, wetted uniformly and dried at 40-50° C. to obtain granules.
Formulation Example 3
A mixture of 4 parts by weight of the active compound (a-1), 4 parts by weight of the active compound (b-3), 10 parts by weight of ethylene glycol, 3 parts by weight of polyoxyalkylene tristyrylphenyl ether, 10 parts by weight of xanthan gum, 0.5 parts by weight of 14% silicone oil emulsion and 68.5 parts by weight of water is well stirred and then crushed with a crusher (Dyno-Mill Type KDL) to obtain water suspension formulation.
Formulation Example 4
5 Parts by weight of the active compound (a-1), 15 parts by weight of the active compound (b-4), 30 parts by weight of sodium ligninsulfonate, 15 parts by weight of parts bentonite and 35 parts by weight of calcined diatomaceous earth powder are well mixed, added with water, well kneaded, extruded with 0.3 mm screen and dried to obtain water dispersible granules.
INDUSTRIAL APPLICABILITY
The herbicide composition for paddy field of the present invention shows, as shown in the aforementioned test examples, precise controlling effect against various kinds of paddy field weeds and an excellent residual effect.
Having thus described in detail various embodiments of the present invention, it is to be understood that the invention defined by the above paragraphs is not to be limited to particular details set forth in the above description as many apparent variations thereof are possible without departing from the spirit or scope of the present invention.

## Claims

1. A herbicide composition for a paddy field characterized by comprising a synergistic combination of components (a) and (b), wherein
(a) is one or more difluoromethanesulfonamide derivatives represented by the formula (I),




wherein
X represents fluorine,
Y represents CH or N,
R1 represents hydrogen, and
R2 represents hydroxy,
and (b) is ethoxysulfuron.

2. A composition according to claim 1, characterized in that
Y represents N.

3. A composition according to claim 1, characterized in that
Y represents CH.

4. A composition according to claim 1, characterized in that it comprises compound (b) in the range of 0.05-200 parts by weight to 1 part by weight of the compound (a).

5. A composition as claimed in claim 2, characterized in that it comprises compound (b) in the range of 0.05-200 parts by weight to 1 part by weight of the compound (a).

6. A composition as claimed in claim 3, characterized in that it comprises compound (b) in the range of 0.05-200 parts by weight to 1 part by weight of the compound (a).

7. Method for controlling weeds in a paddy field which comprises applying to the weeds, parts of the weeds, weed seeds or their habitat, optionally in the presence of a crop, the herbicidal composition of claim 1
wherein the components (a) and (b) are applied simultaneously or sequentially, and wherein the components are defined as in claim 1.

8. Method as claimed in claim 7, characterized in that
Y represents or N.

9. Method as claimed in claim 7, characterized in that
Y represents CH.

10. Method as claimed in claim 7, wherein the crop is rice.

11. Method according to claim 7, characterized in that it comprises compound (b) in the range of 0.05-200 parts by weight to 1 part by weight of the compound (a).

12. Method according to claim 8, characterized in that it comprises compound (b) in the range of 0.05-200 parts by weight to 1 part by weight of the compound (a).

13. Method according to claim 9, characterized in that it comprises compound (b) in the range of 0.05-200 parts by weight to 1 part by weight of the compound (a).