CN108290862B

CN108290862B - Herbicidal compositions and methods for controlling plant growth

Info

Publication number: CN108290862B
Application number: CN201680070825.8A
Authority: CN
Inventors: 詹姆斯·蒂莫西·布里斯托
Original assignee: Jiangsu Rotam Chemical Co Ltd
Current assignee: Jiangsu Rotam Chemical Co Ltd
Priority date: 2015-12-23
Filing date: 2016-09-12
Publication date: 2021-03-23
Anticipated expiration: 2036-09-12
Also published as: WO2017107579A1; GB201522805D0; GB2545726A; TWI726958B; TW201725988A; GB2545726B; CN108290862A

Abstract

A synergistic herbicidal composition is provided comprising a herbicidally effective amount of (a) metribuzin and (B) flazasulfuron. A method of controlling the growth of plants at a locus which comprises applying to the locus a herbicidally effective amount of metribuzin and flazasulfuron.

Description

Herbicidal compositions and methods for controlling plant growth

Cross Reference to Related Applications

This application claims priority from uk patent application GB1522805.9 filed on 23/12/2015, the contents of which are incorporated herein by reference in their entirety.

The present invention relates to herbicidal compositions. The present invention also relates to a method of controlling the growth of undesirable vegetation, particularly in crops, which comprises the use of the aforementioned composition.

The inhibition of crop growth by undesirable plants, and the protection of crops from undesirable plant inhibition is a long-standing problem in agriculture. To address this problem, researchers are attempting to develop a wide range of chemicals and chemical formulations that can effectively control such undesirable plant growth. Many types of chemical herbicides have been disclosed in the literature, and a large number are in commercial use.

Some herbicidal active ingredients have proven to be more effective when applied in combination than when applied individually. This effect is called "synergy". According to the Handbook of herbicides of the Society of Weed Science of America (Herbicide Handbook of the Weed Science Society of America), seventh edition, 1994, page 318, "synergism" is the interaction of two or more factors such that the effect in combination is greater than would be predicted based on the response to each factor applied alone.

Metribuzin and flapwyrisulfuron (flupyrsulfuron) are known as two herbicidally active compounds and are used to control undesirable plant growth. Metribuzin and flazasulfuron are both disclosed in The pesticide Manual (The Pesticides Manual) published by The British Crop Protection Council (The British Crop Protection Council), twelfth edition, 2000. Both compounds are also commercially available as a series of compositions.

Metribuzin (IUPAC name: 4-amino-6-tert-butyl-4, 5-dihydro-3-methylsulfanyl-1, 2, 4-triazin-5-one); 4-amino-6-tert-butyl-3-methylsulfanyl-1, 2, 4-triazin-5 (4H) -one has the following chemical structure:

metribuzin is an inhibitor of plant photosynthesis. The compound can be absorbed by the roots and leaves of the plant and then transferred into the xylem. Metribuzin is effective in controlling grasses and broadleaf weeds. Metribuzin is commercially available as a herbicidal composition and methods for its preparation are known in the art.

Flazasulfuron sodium (IUPAC name: methyl 2- (4, 6-dimethoxypyrimidin-2-ylcarbamoylsulfamoyl) -6-trifluoromethylnicotinate monosodium salt) has the following chemical structure:

flazasulfuron sodium is commercially available and methods for its preparation are known in the art. Flazasulfuron sodium is an inhibitor of branched chain amino acid synthesis (ALS). The compounds act by inhibiting the biosynthesis of the essential amino acids valine and isoleucine, thereby stopping cell division and plant growth in plants.

Most surprisingly, it has now been found that metribuzin and flazasulfuron show a synergistic effect in controlling plant growth when applied in combination, for example in a composition comprising both compounds, or when applied separately to the locus to be treated.

The synergistic effect of the present invention may provide one or more of a number of advantages over the use of the components (a) metribuzin and (B) fluazisulfuron-methyl alone. In particular, the application rates of the individual components can be significantly reduced while maintaining a high level of herbicidal efficacy of the two compounds. Compositions comprising both components may exhibit activity against a considerably wider range of weeds than either component applied alone. Further, compositions comprising both components have the potential to control weed species at lower application rates at which the individual components alone are ineffective. These components may exhibit a greater rate of action when administered in combination than the individual components.

In a first aspect, the present invention provides a composition comprising a herbicidally effective amount of (a) metribuzin and (B) flazasulfuron.

The term "herbicide" as used herein refers to a compound that exhibits activity in controlling plant growth. The term "herbicidally effective amount" as used herein refers to an amount of such a compound or combination of such compounds that is capable of exerting a controlling effect on plant growth. Control includes all differences from the natural development and growth of a plant, including, for example, killing the plant, retarding one or more aspects of plant development and growth, leaf scald, albinism, dwarfing, and the like.

The term "plant" as used herein refers to all material parts of a plant, including shoots, leaves, needles, stalks, stems, fruit bodies, fruits, seeds, roots, tubers and rhizomes.

As described above, the present invention relates to a synergistic herbicidal composition comprising a herbicidally effective amount of (a) metribuzin and (B) flazasulfuron to control the growth of undesirable plants.

In other aspects, the invention provides a method of controlling undesired vegetation which comprises applying to the vegetation or the locus thereof a herbicidally effective amount of (a) metribuzin and (B) flazasulfuron.

In one embodiment, the methods of the present invention employ the above-described compositions.

In a still further aspect, the invention provides the use of a combination of metribuzin and flazasulfuron to control the growth of plants at a locus.

The compositions and methods of the present invention are useful for controlling undesirable plant growth in a range of crops including cereals, legumes, fiber plants and vegetables. Control of undesired vegetation in such crops can be achieved by applying appropriate amounts of metribuzin and flazasulfuron to the plants to be controlled or to their locus. The active compounds may be applied to the locus together or separately. If administered separately, the active compounds can be administered simultaneously and/or sequentially. The method of control may comprise applying to the plant or locus thereof a herbicidally effective amount of the herbicidal composition.

The methods and compositions of the present invention can be used to control the growth of a range of different undesirable plants. (A) The species range of metribuzin and (B) flazasulfuron, i.e. the weed species controlled by the corresponding compounds, is broad and highly complementary.

However, it has surprisingly been found that the combination of metribuzin and flazasulfuron exhibits a very significant synergistic effect in controlling many common weeds, including broadleaf weeds, grasses and sedges, for example, Abutilon spp, copperleaf, spiny, Amaranthus spp, salbutas spp, swine, juglans spp, setaria spp, Anoda spp, setaria spp, Camelina (Capsella spp.), Cardamine (Cardamine spp.), Cassia (Cassia spp.), Tribulus spp.), Agrimonia (Ceratonium spp.), Veratri (Ceratonium spp.), Chenopodium (Chenopodium spp.), Nerium (Chlorospora spp.), Cyperus (Cypermus spp.), Cymbopogon (Dactylocerula spp.), Gymnodinium (Daturaea spp.), Datura spp., Descurainia (Descurainia spp.), Desmodium (Desmodium spp.), Dimocularia spp.), Espera spp., Gemma Agrimonia (Thymus spp.), Gemma spp.), Espera spp., Gemma Agrimonia (Gemma spp.), Espertium spp.), Gemma spp., Espergyrium (Espergyrium spp.), Erythium (Gemma spp.), Erythium spp., Gemma spp.), Erythium (Ecklonia spp.), Erythium spp., Gemma spp., Ecklonium spp., Gemma (Evonigerea (Evop, Gemma spp.), Ecklonium spp.), Echinotrysum (Evonigerea (Evop (Evonigella (Evop), Gemma spp.), Erythium spp.), Eclipp (Evonigerba (Evonigella (Evop, Evosporum (Evonigella, Evospo (Evop, Evonigella (Evop), Gemma spp.), E, Strobilus (nigella spp.), weasella (Galeopsis spp.), achyranthes (galinogia spp.), cleavers (Galium spp.), Geranium (Geranium spp.), crowndaisy (Glehionis spp.), crowndaisy (Gleionis spp.), sunflower (Helianthus spp.), Hibiscus (Hibiscus spp.), barley (Hordeum spp.), Ipomoea (Ipomoea spp.), petunia (Microphyllanthus spp.), petunia (Jacquenothia spp.), Kochia (Kochia spp.), lettuce (Lactuca spp.), picrasma (Lamiusmus spp.), strium spp.), Meadowrue (Lepidium spp.), Meadowrue (Melothria spp.), Loropera (Melothria spp.), Loranthus spp (Melothria spp.), Loranthus spp.), Meadowrue spp.), Loranthus spp., Melothria spp.) Rice (cottza spp.), millet (Panicum spp.), poppy (Papaver spp.), Polygonum (Persicaria spp.), poaceae (Poa spp.), allium (pollenum spp.), Polygonum (Polygonum spp.), Portulaca (Portulaca spp.), Ranunculus (Ranunculus spp.), radish (Raphanus spp.), resenocerous (Reseda spp.), lucerne (Medicago sativa spp.), Rumex (Medicago spp.), Rumex (Rumex spp.), physalsa spp.), senecium (senula spp.), senecium (Senecio spp.), stigma (Senecio spp.), Setaria spp., sella (Senecio spp.), sella spp.), selinula (Senecio spp.), sella (senecila spp.), sella spp., sella (senula spp.), sella spp., sola (sola spp.), sella spp., sola (sola spp.), sella spp.), celago spp.), celiac (sola spp.), celiac (sola spp.), celago spp.), celiac (sola spp.), celiac) and senna spp. (senna spp.) (Solanum spp. (senna spp.) (solani spp.) (senna spp.) (sen, Trilobate (Trifolium spp.), Triticum (Triticum spp.), nettle (Urtica spp.), malva (Vaccaria spp.), salmonum (Veronica spp.), Vicia (Vicia spp.), Viola (Viola spp.), and Xanthium (xanthum spp.).

The combination of metribuzin and flazasulfuron is particularly effective in controlling: chorionic villous leaf (Abutilon theoprasta); acalypha australis (Acalypha australis); sphaeranthus fruticosus (Bristly Starbur, Acanthospermum hispidum); radix cercis mairei (cornockle, Agrostemma gitnago); myrtle (Blackgrass, Alopecurus mycoides); wild amaranth (Amaranthus spp.); pig grass (Common Ragweed, ambrosiaarteisifolia); camomile flowers (Tarweed Fiddleneck, Amsinckia lycopsides); a dotted sunflower (normal Anoda, Anoda cristata); chamomile (Anthemisertula)); cleavers (Elimina species) (Euphorbia peltata (Aspergo procumbens)); atriplex canescens (Common Orache) (Atriplex patula); wild oat (Wild-Oat, Avena fatua); wild oats (avena); herba Hedyotidis Diffusae (Boraginaceae); broadleaf sempervivum (brachypodium platyphylla); volunteer rape (volnterer oil rape) (Brassica napus); wild mustard (brassica); bromus palustris (Rescuegras, Bromus cataticus); brome (Japanese bromine, Bromus japonica); canary (riput broome, Bromus rigidus); sparrow wheat (cheetgrass, Bromus harvester); camelina sativa (Camelina microcarpa); shepherd's purse (Capsella bursa-pastoris); cardamine hirsuta (Bittercress, Cardamine hirsuta); cassia tora (Cassia obtipod, Cassia obtusifolia); tribulus terrestris (Tribulus); chickweed, white fungus (mousea, Cerastium vulgatum); chenopodium album (Fat-hen, Chenopodium album); chenopodium album (chenopodium); ion mustard (Blue mustard, Chorispora tenella); primrose (Miners lette, Claytonia perfoliata); canna canadensis (horseweeed Marestail, Conyza canadensis); cyperus esculentus (Yellow nutswedge, Cyperus esculentus); cogongrass (crowfoot grass, dactylotenium aegyptium); stramonium (Jimsonweed, Datura stramnonium); artemisia anethoides (Tansy mustard) (Descurainia pinnata); desmodium flabellifolium (Desmodium fortunei) s; crabgrass (Crabgrass) (genus Crabgrass); herba Botrychii (Spring whitlowgrass) (Frnals) (Draba verna)) in Spring; junglerice (Echinochloa colonum); barnyardgrass (Barnyardgrass, Echinochloa crus-galli); goosegrass (goose grass, Eleusine indica); common creeping grass (Common corn) (Elymus repens)); bolbostemma (teff); cupola (cupras) (southwestern broomcorn millet (Eriochloa gracilis)); herba Pteridis Multifidae (Redstem fileee) (Erodium cicutarium); eupatorium adenophorum (Dogfennel, Eupatorium capllifolium); sun spurge (European heliosporia); euphorbia maculata (Spotted Spurge, Eurorbia maculata); polygonum convolvulus (Black-bindweed, Fallopia convolulus); plants of the genus corydalis (corydalis officinalis (Fumaria officinalis)); petals (weasel petals); achyranthes bidentata (achyranthes); cleavers (Galium aparine); geranium plants (crane's-bill) (Geranium); geranium (geranium); pearl chrysanthemum (Corn Marigold) (Chrysanthemum indicum (Glebais segetum)); sunflower (genus helianthus); watermelon seedlings (Venice Mallow, Hibiscus trionum); small barley (Little barley, Hordeum pusillum); morning glory (Ivyleaf morningqlorv) (Ipomoea hederacea)); petunia (Ipomoea lacunaosa); morning glory (Tall morningqloray) (round leaf morning glory); petunia (Smallflower morningqlorv) (jacquengoia (Jacquemontia tamnifolia)); kochia scoparia (Kochia scoparia); lactuca sativa (Lactuca seriola); gelidium amansicaue (Lamium amplexicaule); sesamom indicum (Lamium purpureum); striga asiatica (Lepidium virginicum); leptospira (Leptochloa spp.); lithospermum (Lithospermum spp.); perennial ryegrass (Lolium perenne); chamomile (pineapple) (Matricaria discoidea); red weeds (red weed) (masson pine (Melochia corifolia)); yamao blue (Annual marcury) (western indigowoad (Mercurialis annua)); chestnut (molugo Verticillata); myosotis sylvatica (Field for get-me-not) (Myosotis arvensis); evening primrose (Oenothera lacini ta); red rice (Oryza sativa); couch grass (Panicum cap/Hare); sorghum sugaense (Panicum dichotomiforum)); brown top Millet (brown top Millet) (Panicum ramosus); panicum (panitumtaxum); poppy flower (Papaver rhoeas); polygonum majorana (Pale Persicaria) (Persicaria lapathifolia); polygonum hydropiper (Persicaria maculosa); annual meadow-grass (Poa annua); blue grass (annual bluegrass); poa pratensis (Poa bulbosa); allium genus annual onion (Polemonium miranthum); stoloniferous shallots (pollenium reptans); polygonum crawlers (Polygonum aviculare); wild buckwheat (Polygonum convolulus); polygonum (Polygonum spp.); purslane (Portulaca oleracea); buttercup (Ranunculus spp.); wild radish (Raphanus raphnistum); wild luteolin (resedalute); purslane florida (lucerne (Richardia scabra)); rumexacetosella (Rumexacetosella); senecio scandens (Senecio); sesbania (Sesbania spp.); setaria spp; green bristlegrass (Setaria viridis); russian thistle (Sida spinosa) in the morning; white mustard (Sinapis arvensis); carmustine (gamble mustard) (Jim Hill) (garlic (Sisymbrium altissimum)); sida acuta/Teaweed (Slda spinosa); black nightshade (Solanum nigrum); solanum rostratum (Buffalobur) (Solanum rostratum)); herba Sonchi arvensis (Sonchus oleraceus); shattercane (Sorghum saccharatum (Sorghum bicolor)); sorghum halepense (Sorghum halepense); sorghum (Sorghum spp); ottelia macrogola (Spergula arvensis); chickweed (Stellaria media); herba Patriniae (Thlaspi arvense); clover (Trifolium); volunteer wheat (triticum spp.); small nettle (Urtica urens); cabbage (Vaccaria hispanica); veronica officinalis (Veronica hederifolia); veronica spp (Veronica spp); winter garden pea (Vicia villosa); pansy (Viola arvensis); and Xanthium (Xanthium Pensylvanicum).

It has been found that the compositions and methods of the present invention are particularly useful for controlling the growth of: brassica; amaranth; genus Helianthus; capsella; datura genus; genus digitaria; barnyard grass; 26926genus; geranium; genus picrasma; euphorbia; sinapis alba; solanum genus; stellaria species; veronica; xanthium species.

In particular, the combination of (a) metribuzin and (B) fluazisulfuron-methyl has been found to be effective in controlling: amaranthus, mallow, brassica napus, capsella bursa-pastoris, stramonium, digitaria sanguinea, digitaria nodosa, barnyard grass, eleusine indica, geranium, pagodatree, sesameia indica, moleplant, eruca sativa, solanum nigrum, chickweed, salmond, cocklebur, etc.

When combined or used together, the synergistic effect of (a) metribuzin and (B) fluazisulfuron-methyl is exhibited over a wide range of weight ratios of the two components. In the compositions and methods of the present invention, the weight ratio of (A) metribuzin and (B) flazasulfuron is preferably at most 400: 1, more preferably at most 200: 1, still more preferably at most 150: 1, still more preferably at most 100: 1, and in many embodiments a ratio of at most 70: 1 is preferred. (A) The weight ratio of metribuzin and (B) flazasulfuron is preferably greater than 1: 20, more preferably greater than 1: 10, still more preferably greater than 1: 5, still more preferably greater than 1: 2, and a ratio of about 1: 1 is suitable for many embodiments. The weight ratio of metribuzin to flazasulfuron is preferably in the range of about 200: 1 to about 1: 1. Preferably, the weight ratio of (A) metribuzin and (B) flazasulfuron is from about 100: 1 to about 1: 1, more preferably from about 70: 1 to about 2: 1, still more preferably from about 70: 1 to about 5: 1, still more preferably from about 70: 1 to about 10: 1.

The active synergistic components may be present in the compositions of the present invention in a wide range of amounts. In a preferred embodiment, the total amount of (a) metribuzin and (B) flazasulfuron is from about 5% to 99% by weight of the composition, more preferably from 10% to 80% by weight of the composition, still more preferably from 15% to 75% by weight of the composition.

The metribuzin present in the composition may be in an amount of from 5% to 95% by weight of the composition, more preferably from 10% to 80% by weight of the composition, still more preferably from 15% to 75% by weight of the composition. The flazasulfuron may be present in the composition in an amount of 0.01% to 50% by weight, preferably 0.05% to 20% by weight, still more preferably 0.1% to 10% by weight, still more preferably 0.1% to 5% by weight. In some embodiments of the invention, the composition comprises 5% to 95% by weight of (a) metribuzin and 0.01% to 50% by weight of (B) flupyrsulfuron-methyl. Preferably, the composition comprises from 10% to 75% by weight of (a) metribuzin and from 0.1% to 10% of (B) flupyrsulfuron-methyl. More preferably, the composition comprises from 20% to 55% by weight of (a) metribuzin and from 0.1% to 5% by weight of (B) flupyrsulfuron-methyl.

In general, the application rates of the active ingredients metribuzin and flazasulfuron depend on factors such as the type of weeds, the type of crop plants, the type of soil, the season, the climate, the soil ecology and various other factors. The rate of application of the composition for a given set of conditions can be readily determined by routine experimentation.

Generally, the compositions and methods of the present invention can be applied at an application rate of about 0.05 kilograms per hectare (kg/ha) to about 2kg/ha of the total amount of the active ingredients (a) metribuzin and (B) flazasulfuron applied. Preferably, the application rate is from about 0.1kg/ha to about 1.5kg/ha of the total amount of active ingredients. Metribuzin can be applied at a rate of from 10g/ha to 1500g/ha, more preferably from 100g/ha to 1000g/ha, still more preferably from 200g/ha to 600 g/ha. Flazasulfuron may be applied at a rate of 1g/ha to 500g/ha, preferably 1g/ha to 100g/ha, more preferably 1g/ha to 50 g/ha. In some embodiments of the invention, the application rate of the active ingredients is from 10g/ha to 1500g/ha of (A) metribuzin and from 1g/ha to 500g/ha of (B) flupyrsulfuron-methyl. Preferably, the application rates of the active ingredients are from 100g/ha to 1000g/ha of (A) metribuzin and from 1g/ha to 100g/ha of (B) flupyrsulfuron-methyl. More preferably, the application rates of the active ingredients are from 200g/ha to 600g/ha of (A) metribuzin and from 1g/ha to 40g/ha of (B) flupyrsulfuron-methyl.

As mentioned above, in the present invention metribuzin and flazasulfuron may be applied to plants and/or their locus separately or as a combination of parts of a two part herbicide system (e.g. a composition of the present invention). When administered separately, metribuzin and flazasulfuron may be administered simultaneously and/or sequentially.

The compositions of the present invention may be formulated in conventional manner, for example by mixing metribuzin and flazasulfuron with suitable adjuvants. Suitable adjuvants will depend on factors such as the type of formulation and end use. Suitable auxiliaries are commercially available and known to the person skilled in the art.

In particular, the composition may further comprise one or more adjuvants selected from: fillers, carriers, solvents, surfactants, stabilizers, defoamers, antifreeze agents, preservatives, antioxidants, colorants, thickeners, solid adhesion agents, fillers, wetting agents, dispersants, lubricants, antiblocking agents, and diluents. Such adjuvants are known in the art and are commercially available. Their use in the formulation of the compositions of the present invention will be apparent to those of ordinary skill in the art.

Suitable formulations for applying the combination of metribuzin and flazasulfuron as well as the composition of the invention include soluble Solution (SL), Emulsifiable Concentrate (EC), aqueous Emulsion (EW), Microemulsion (ME), Suspension Concentrate (SC), oil-based suspension concentrate (OD), suspended seed coating (FS), water dispersible granule (WG), Soluble Granule (SG), Wettable Powder (WP), Soluble Powder (SP), Granule (GR), micro-Capsule Granule (CG), Fine Granule (FG), macrogranule (GG), Suspoemulsion (SE), micro-Capsule Suspension (CS) and Microgranule (MG).

Preferred formulation types for the composition of the present invention are suspending agents (SC), water dispersible granules (WG), Soluble Granules (SG) and Wettable Powders (WP).

The composition may comprise one or more inert fillers. Such inert fillers are known in the art and are commercially available. Suitable fillers include, for example, naturally ground minerals such as kaolin, alumina, talc, chalk, quartz, attapulgite, montmorillonite and diatomaceous earth; or synthetic ground minerals such as highly dispersed silicic acid, alumina, silicates, and calcium hydrogenphosphates. Suitable inert fillers for the granules include, for example, crushed and fractionated natural minerals (such as calcite, marble, pumice, sepiolite and dolomite), or synthetic granules of inorganic and organic abrasive materials, and granules of organic materials (such as sawdust, coconut shells, corn cobs, and tobacco stalks).

The composition may comprise one or more surfactants, which are preferably nonionic, cationic and/or anionic in character, and which are mixtures of surfactants with good emulsifying, dispersing and wetting properties, depending on the active compound being formulated. Suitable surfactants are known in the art and are commercially available.

Suitable anionic surfactants may be both so-called water-soluble soaps (water-soluble soaps) and water-soluble synthetic surface-active compounds (water-soluble synthetic surface-active compounds). Soaps that may be used include higher fatty acids (C)₁₀-C₂₂) Or a substituted or unsubstituted ammonium salt, for example, a sodium or potassium salt of oleic or stearic acid, or a sodium or potassium salt of a natural fatty acid mixture.

The surfactant system may comprise an ionic or non-ionic emulsifier, dispersant or wetting agent. Examples of such surfactants include salts of polyacrylic acids, salts of lignosulfonic acids, salts of benzenesulfonic or naphthalenesulfonic acids, polycondensates of ethylene oxide with fatty alcohols or with fatty acids or with fatty amines, substituted phenols (especially alkylphenols), sulfosuccinate ester salts, taurine derivatives (especially alkyl taurates), and phosphoric esters of polyethoxylated phenols or alcohols.

The presence of at least one surfactant is generally required when the active compound and/or inert carrier and/or adjuvant/adjuvant is not soluble in water and the medium for the final application of the composition is water.

The composition optionally further comprises one or more polymeric stabilizers. Suitable polymeric stabilizers that may be used in the present invention include, but are not limited to: polypropylene, polyisobutylene, polyisoprene, copolymers of monoolefins and diolefins, polyacrylates, polystyrene, polyvinyl acetate, polyurethanes or polyamides. Suitable stabilizers are known in the art and are commercially available.

It is generally believed that the surfactants and polymeric stabilizers described above impart stability to the composition, thereby allowing the composition to be formulated, stored, transported, and applied.

Suitable antifoaming agents include all substances which can be used for this purpose in agrochemical compositions in general. Suitable defoamers are known in the art and are commercially available. Particularly preferred defoamers are mixtures of polydimethylsiloxanes and perfluoroalkylphosphonic acids, for example silicone defoamers commercially available from GE or Compton (Compton).

Suitable solvents for inclusion in the composition may be selected from all common organic solvents which completely dissolve the active compounds metribuzin and flazasulfuron. In addition, suitable organic solvents for metribuzin and flazasulfuron are known in the art. The following solvents may be considered preferred: n-methylpyrrolidone, N-octylpyrrolidone, cyclohexyl-1-pyrrolidone; or mixtures of paraffinic, isoparaffinic, naphthenic and aromatic hydrocarbons, e.g. SOLVESSO^TM200. Suitable solvents are commercially available.

Suitable preservatives for use in the compositions of the present invention include all materials which may be conventionally used for this purpose in agrochemical compositions of this type and are also well known in the art. Suitable examples which may be mentioned include commercially available preservatives

(from Bayer AG) and

(from bayer).

Suitable antioxidants for use in the compositions of the present invention are all substances which can be used for this purpose in agrochemical compositions in general, as known in the art. Butylated hydroxytoluene is preferred.

Suitable thickeners for use in the composition include all materials which are commonly used for this purpose in agrochemical compositions, for example xanthan gum, PVOH, cellulose and its derivatives, clay hydrated silicates, magnesium aluminium silicate or mixtures thereof. Again, such thickeners are known in the art and are commercially available.

The composition may further comprise one or more solid attachment agents. Such adhesives are known in the art and are commercially available. They include organic binders including tackifiers, such as cellulose or substituted cellulose, natural and synthetic polymers in the form of powders, granules or latices, and inorganic binders, such as gypsum, silica or cement.

In the methods and uses of the invention, the combination of the active ingredients metribuzin and flazasulfuron may be applied to the plants by any convenient means, for example to the foliage of the plants and/or the locus where they are desired to be controlled, such as the surrounding soil. By "locus" is meant the location where the plant is growing, the location where the plant propagation material of the plant is sown, or the location where the plant propagation material of the plant is to be sown.

As mentioned above, the present invention also relates to the use of a combination of metribuzin and flazasulfuron, for example in a composition or formulation as described above, to control or modify the growth of undesirable plants in a crop. The combination of metribuzin and flazasulfuron may be used to treat a range of crops, including cereals such as wheat, barley, rye, oats, maize, rice, sorghum, triticale and related crops; beets, such as sugar beets and fodder beets; fruits such as pomes, stone fruits and soft fruits (e.g., apples, grapes, pears, plums, peaches, almonds, cherries and berries (e.g., strawberries, raspberries and blackberries)); leguminous plants, such as beans, lentils, peas, soybeans and peanuts; oil plants such as rape, mustard and sunflower; cucurbitaceae, such as zucchini, cucumber and melon; fiber plants, such as cotton, flax, hemp and jute; citrus fruits such as oranges, lemons, grapefruits and mandarins; vegetables such as spinach, lettuce, asparagus, cabbage, carrot, onion, tomato, potato and red pepper; ornamental plants, such as flowers, shrubs, broad-leaved trees and evergreens (e.g., conifers) and sugar cane.

In a preferred embodiment, the method or composition of the invention is used for controlling the growth of undesired plants in cereals, legumes, fiber plants and vegetables, preferably in wheat, barley, rye, oats, corn, rice, sorghum, triticale, beans, lentils, peas, soybeans and peanuts, cotton, flax, hemp, jute, spinach, lettuce, asparagus, cabbage, carrots, onions, tomatoes, potatoes and red peppers, more preferably in wheat, barley, corn, rice, soybeans, cotton, tomatoes and potatoes.

Suitable crops that may be treated include those that are resistant to metribuzin and flazasulfuron. Tolerance may be natural tolerance produced by selective breeding, or may be artificially introduced by genetic modification of crop plants. In this respect, 'tolerance' means low sensitivity to damage caused by one or more specific herbicides (in this case metribuzin and flazasulfuron).

The active ingredients employed in the practice of the present invention may be administered in a variety of concentrations in a variety of ways known to those skilled in the art. The methods and compositions of the present invention are useful for controlling the growth of undesirable plants by applying the active ingredients to the plants and/or their locus to be controlled before planting, before germination and/or after germination.

The active ingredients metribuzin and flazasulfuron may be applied to the undesired plants and crops to be protected and/or their locus by conventional methods including coating, spraying, sprinkling, dipping, soaking, injection, irrigation and the like.

The method of the present invention may employ other pesticides in addition to the combination of metribuzin and flazasulfuron. For example, the compositions of the present invention may contain or be mixed with other pesticides (e.g., fungicides, insecticides, and nematicides), growth factor enhancers, and fertilizers to enhance the treatment activity of the present invention or to broaden its range of activity. Similarly, the methods of the present invention may be used in conjunction with one or more of the aforementioned active ingredients, again to achieve enhanced efficacy or a broader range of activity.

Embodiments of the present invention will now be described by way of the following examples for illustrative purposes only.

Percentages are by weight unless otherwise specified.

Examples

Formulation examples

A water dispersible granule (WG) was prepared by: mixing and grinding the active ingredients and the auxiliaries (0.5) under compressed air％

(sodium lauryl sulfate, Witco Inc. (Witco Inc.), Greenwich), 5%

88B (sodium lignosulfonate, Weishi Vickers (Westvaco Corp)), potassium carbonate (make up to 100%), then wetted, extruded and dried to obtain water dispersible granules.

For example, a water dispersible granule (WG) formulation was prepared from the following components:

the Suspension (SC) was prepared by mixing the finely ground active ingredient with adjuvants (10% propylene glycol, 5% tristyrylphenol ethoxylate, 1% sodium lignosulfonate, 1% carboxymethylcellulose, 1% silicone oil (in the form of a 75% aqueous emulsion), 0.1% xanthan gum, 0.1% NIPACIDE BIT 20, water (1L make up).

For example, a Suspension (SC) formulation was prepared from the following components:

soluble Granules (SG) were prepared by: the active ingredient and the adjuvant (0.5%

(sodium lauryl sulfate, Litheco, Greenwich.) 5%

88B (sodium lignosulfonate, Weishiweck company) and 2% sodium bicarbonate (NaHCO)₃) Potassium sulfate (to make up 100%)), then wetted, extruded and dried to obtain soluble granules.

For example, a Soluble Granule (SG) formulation was prepared from the following components:

by mixing and grinding the active ingredients and adjuvants (5%

1494；8％

622S, Kaolin (to make up 100g) A Wettable Powder (WP) formulation was prepared.

For example, Wettable Powder (WP) formulations were prepared from the following components:

a series of formulation forming examples 1 to 9 were prepared according to the above method. The formulation types and active ingredient contents are summarized in table a below.

Examples 1 and 2 are comparative examples.

TABLE A

Biological examples

The combination of two active compounds shows a synergistic effect when the activity of the combination of the two active compounds is greater than the sum of the activities of the two active compounds administered alone.

The expected activity of a given combination of two active compounds can be calculated by the so-called "coll ratio (Colby) formula" (see s.r. coll ratio (Colby), "Calculating the Synergistic and Antagonistic Responses of Herbicide Combinations" (Weeds)1967, 15, 20-22):

whereby:

E＝A+B-(A×B/100)

wherein:

a ═ the percentage of activity of compound a when active compound a was used at an administration rate of mg/ha;

b-percent activity of compound B when used at an application rate of ng/ha;

e-percentage activity estimated when compounds a and B were used together at the administration rates of mg/ha and ng/ha.

If the actual activity observed for the combination of compounds a and B is greater than the activity calculated using the above formula, the activity of the combination is superadditive, i.e. there is a synergistic effect.

Biological example 1

Wheat, barley and corn plants were sown in randomized plots of the field. The different types of weeds present in each plot, as well as their relative densities, were identified and are listed in table 1 below.

The compositions according to examples 1 to 9 were applied by spraying 50 days after planting. After spraying, the blocks were kept for about 2 weeks.

Two weeks after application, the plots were examined to determine the efficacy of each formulation in controlling weed growth. The results are given in table 2 below.

The efficacy of the treatment in controlling weed growth is expressed as the percentage of weeds killed after the treatment.

Table 1: weed type

Weed type	Relative density (%)
		Brassica napus	10
Capsella bursa-pastoris	15
		Geranium	15
All-grass of Jasminum sessiliflorum	20
		Herb of Japanese Galium	10
Root of Whiteflower mustard	5
		Chickweed	20
Herba Veronicae Divaricati	5

As can be seen from the results given in table 2, the formulations of the present invention comprising a combination of metribuzin and flazasulfuron exhibited a significantly increased effect in controlling the target weeds compared to the effects of metribuzin and flazasulfuron alone or predicted from the combination of the two active ingredients. This increased effect clearly shows a synergistic effect between the two active ingredients.

Biological example 2

Soybean and cotton plants were sown in randomized plots of the field. The different types of weeds present in each plot, as well as their relative densities, were identified and are listed in table 3 below.

The compositions according to examples 1 to 9 were applied by spraying 50 days after planting. After spraying, each block was kept for about 2 weeks.

Two weeks after application, each plot was examined to determine the efficacy of each formulation in controlling weed growth. The results are given in table 4 below.

TABLE 3 weed types

Weed type	Relative density (%)
		Amaranthus	20
Bingzhou cocklebur	10
		All-grass of Datura	20
Spaced single flower sunflower	10
		Barnyard grass	25
Capsella bursa-pastoris	15

As can be seen from the results given in table 4 above, the formulations of the present invention comprising a combination of metribuzin and flazasulfuron exhibited a significantly increased effect in controlling the target weeds compared to the effects of metribuzin and flazasulfuron alone or predicted from the combination of the two active ingredients. The effect of this increase clearly indicates a synergistic effect between the two active ingredients.

Biological example 3

Tomato and potato plants were sown in randomized plots of the field. The different types of weeds present in each plot, as well as their relative densities, were identified and are listed in table 5 below.

Two weeks after application, each plot was examined to determine the efficacy of each formulation in controlling weed growth. The results are given in table 6 below.

Table 5: weed type

Weed type	Relative density (%)
		Barnyard grass	25
Solanum nigrum	20
		Amaranthus	10
Chickweed	15
		Herba Veronicae Divaricati	20
Perennial ryegrass	10

As can be seen from the results given in table 6, the formulations of the present invention comprising a combination of metribuzin and flazasulfuron exhibited a significantly increased effect in controlling the target weeds compared to the effects of metribuzin and flazasulfuron alone or predicted from the combination of the two active ingredients. The effect of this increase clearly indicates a synergistic effect between the two active ingredients.

Biological example 4

Rice was sown in randomized blocks of the field. The different types of weeds present in each plot, as well as their relative densities, were identified and are listed in table 7 below.

Two weeks after application, each plot was examined to determine the efficacy of each formulation in controlling weed growth. The results are given in table 8 below.

Table 7: weed type

Weed type	Relative density (%)
		Barnyard grass	20
Genus Euphorbia	15
		Short Tang Dynasty's noddles	25
Shanghangtang (Chinese character of' Shang Tang	25
		All-grass of Bull's tendon	15

As can be seen from the results given in table 8, the formulations of the present invention comprising a combination of metribuzin and flazasulfuron exhibited a significantly increased effect in controlling the target weeds compared to the effects of metribuzin and flazasulfuron alone or predicted from the combination of the two active ingredients. The effect of this increase clearly indicates a synergistic effect between the two active ingredients.

Claims

1. A composition comprising a herbicidally effective amount of (a) metribuzin and (B) flazasulfuron, wherein the weight ratio of metribuzin to flazasulfuron is from 400: 1 to 10: 1.

2. The composition of claim 1, wherein the weight ratio of metribuzin to flazasulfuron is from 200: 1 to 10: 1.

3. The composition of claim 2, wherein the weight ratio of metribuzin to flazasulfuron is from 70: 1 to 10: 1.

4. The composition of claim 1, wherein the total amount of metribuzin and flazasulfuron is between 5% and 99% by weight of the composition.

5. The composition of claim 1, wherein metribuzin is present in an amount of 5% to 95% by weight.

6. The composition of claim 1, wherein flazasulfuron is present in an amount of 0.01% to 50% by weight.

7. The composition of claim 6, wherein the composition comprises 10% to 75% by weight metribuzin and 0.1% to 10% by weight flazasulfuron.

8. The composition of any one of claims 1 to 7, further comprising one or more adjuvants selected from: fillers, carriers, solvents, surfactants, stabilizers, defoamers, antifreeze agents, preservatives, antioxidants, colorants, thickeners, solid adhesion agents, fillers, wetting agents, dispersants, lubricants, antiblocking agents, and diluents.

9. The composition of any one of claims 1 to 7, formulated as a soluble Solution (SL), an Emulsifiable Concentrate (EC), an aqueous Emulsion (EW), a Microemulsion (ME), a Suspension Concentrate (SC), an oil-based suspension concentrate (OD), a suspended seed coating (FS), a water dispersible granule (WG), a Soluble Granule (SG), a Wettable Powder (WP), a Soluble Powder (SP), a Granule (GR), a micro-Capsule Granule (CG), a Fine Granule (FG), a macro-granule (GG), a Suspoemulsion (SE), a micro-Capsule Suspension (CS), or a micro-granule (MG).

10. A method of controlling undesired plant growth, which comprises applying to the plant or the locus thereof a herbicidally effective amount of (a) metribuzin and (B) flazasulfuron, wherein the weight ratio of metribuzin to flazasulfuron is from 400: 1 to 10: 1.

11. The method of claim 10, wherein the undesirable plant growth is controlled in crops including cereals, legumes, fiber plants, and vegetables.

12. The method of claim 11, wherein the controlled plant growth is growth of one or more of broadleaf, grasses, and sedges.

13. A method as claimed in any one of claims 10 to 12, wherein the plant growth controlled is one or more of: brassica (Brassica spp.); amaranthus (Amaranthus spp.); malva spp (Anoda spp.); genus camelina (Capsella spp.); datura (Datura spp.); digitaria spp (Digitaria spp.); barnyard grass (Echinochloa spp.); 26926genus (Eleusines spp.); geranium spp (Geranium spp.); genus picrasma (Lamium spp.); leptospira (Leptochloa spp.); sinapis alba (Sinapis spp.); solanum (Solanum spp.); stellaria spp; grandma (Veronica spp.); xanthium spp.

14. The method of claim 13, wherein the controlled plant growth is one or more of: amaranthus, pelargonium sidoides (Andora cristata), Brassica napus (Brassica napus), Capsella bursa-pastoris (Capsella bursa-pastoris), Datura stramonium (Datura stramonium), Digitaria rosthorniana (Digitaria ciliaris), Digitaria nodosa (Digitaria segregata), Echinochloa barnyard grass (Echinochloa colonum), Echinochloa crusgalli (Echinochloa cruris), Eleusine (Eleuussusine indica), Geranium, Gekko Swinhonis (Lamium amplexicaule), Lamium palustrum (Lamium purpureum), Euphorbia lathyris, Sinapis alba (Sinapium arvensis), Solanum nigrum (Solanagrurum), Stellaria media, Veronica (Veronica), Xanthium sibirica (Xanthium sibirica).

15. The method of any one of claims 10 to 12, wherein the total amount of active ingredients metribuzin and flazasulfuron is applied at an application rate of 0.05 kilograms per hectare (kg/ha) to 2 kg/ha.

16. The method of claim 15, wherein the total amount of active ingredients metribuzin and flazasulfuron is applied at an application rate of 0.1kg/ha to 1.5 kg/ha.

17. The method of any one of claims 10 to 12, wherein metribuzin is applied at an application rate of 10g/ha to 1500 g/ha.

18. The method of claim 17, wherein metribuzin is applied at an application rate of 100g/ha to 1000 g/ha.

19. A method as claimed in any one of claims 10 to 12 wherein the flazasulfuron is applied at an application rate of from 1g/ha to 500 g/ha.

20. A method as claimed in claim 19 wherein the flazasulfuron is applied at an application rate of 1 to 100 g/ha.

21. The method of any one of claims 10 to 12, wherein component (a) and component (B) are applied pre-planting, pre-emergence and/or post-emergence.

22. The method of any one of claims 10 to 12, wherein metribuzin and flazasulfuron are applied to the locus simultaneously.

23. The method of claim 22, wherein a composition of any one of claims 1 to 9 is employed.

24. The method of any one of claims 10 to 12, wherein metribuzin and flazasulfuron are applied to the locus sequentially.

25. The method of any one of claims 10 to 12, wherein the weight ratio of metribuzin to flazasulfuron is from 200: 1 to 10: 1.

26. The method of claim 25, wherein the weight ratio of metribuzin to flazasulfuron is from 70: 1 to 10: 1.

27. The method of any one of claims 10 to 12, wherein the total amount of the active ingredients metribuzin and flazasulfuron applied is applied at a rate of 0.05 kilograms per hectare (kg/ha) to 2 kg/ha.

28. The method of claim 27, wherein the total amount of the active ingredients metribuzin and flazasulfuron applied is applied at a rate of 0.1 kilograms per hectare (kg/ha) to 1.5 kg/ha.

29. Use of a combination of metribuzin and flazasulfuron in controlling the growth of plants at a locus, wherein the weight ratio of metribuzin to flazasulfuron is from 400: 1 to 10: 1.