Method for controlling a weed in an agricultural crop

Abstract

The present invention concerns a method for controlling a weed in an agricultural crop, which comprises applying an effective herbicidal dose of metamitron to the weed or the locus of the weed, or to the agricultural crop or the locus of the agricultural crop, optionally in combination with another phytosanitary active ingredient.

Description

[0001] METHOD FOR CONTROLLING A WEED IN AN AGRICULTURAL CROP

[0002] The present invention concerns a method for controlling a weed in an agricultural crop .

[0003] As is well known, the introduction of herbicides in agriculture has increased the productivity and quality of agricultural crops by limiting weed competition . Without the use of the herbicide-acting products , production losses due to weed competition for space , light , water and nutrients is estimated at 30% to 70% . Environmental science and analytical methodologies , however, have shown that the misuse of herbicides causes serious environmental and health problems , such as water pollution, the development of herbicide resistance by weeds , and herbicide toxicity to nontarget organisms . For this reason, over the years the relevant authorities have increasingly regulated the marketing and use of phytosanitary products including herbicides .

[0004] Depending on their chemical structure , herbicides can have varying degrees of ef ficacy and selectivity . Ef ficacy refers to the herbicide ' s ability to control or modi fy weed development , while selectivity refers to the tolerance of agricultural crops ( so-called "beneficial crops" ) .

[0005] Triazine compounds are among the most widely used herbicides today . Triazine herbicides belong to HRAC group 5 ( PS I I inhibitors - Serine 264 Binders ) according to Herbicide Resistance Action Committee - Mode of Action Classi fication 2022 , www . hracglobal . com) . Triazine herbicides are selective pre- and / or post-emergence herbicides , which act by interfering with electron transport in susceptible plants at the photosystem I I level , inhibiting their photosynthesis and leading to their death .

[0006] Triazine herbicides known in the art include the following compounds : simazine , atrazine , terbuthylazine , and metamitron .

[0007] Simazine has long been used as a broad-spectrum herbicide for weed control in corn, wheat , barley, potato , fruit and vegetable crops . Atrazine , on the other hand, has been used as a selective herbicide against broadleaf weeds in crops of corn, sorghum, fruit trees , vineyards , public greenery, and sugar cane . Because of issues related to their persistence in the environment , toxicity to humans , aquatic organisms and their accumulation in cultivated plants , the marketing and use of simazine and atrazine are now banned in many countries around the world, including Europe .

[0008] Terbuthylazine is a less toxic herbicide than atrazine , although it has a similar spectrum of action to the latter . Thanks to its selectivity and broad spectrum of action on dicotyledonous plants and annual grasses , as well as its better eco-toxicological and toxicological profile than triazine , terbuthylazine has replaced atrazine as an herbicide in agricultural crops such as corn, sorghum, fruit trees , vineyards , and sugar cane . Terbuthylazine also exhibits high compatibility with other phytosanitary active ingredients . This compatibility has made it possible to prepare formulations containing terbuthylazine in combination with a variety of phytosanitary active ingredients , said formulations having a broader spectrum of herbicidal action and being able to prevent the emergence of herbicide-resistant weeds . Examples of phytosanitary active ingredients used are : secbumeton, dichlobenil , bromofenoxim, terbumeton, bromofenoxim, metolachlor, alachlor, chlorpropham, dalapon, pyridate , diuron, mesotrion, dimethenamide-P . In fact , the maj or use of terbuthylazine as an herbicide today is in the form of formulations containing other herbicidally active ingredients .

[0009] However, the use of terbuthylazine also has drawbacks . Indeed, it has been shown that terbuthylazine is highly persistent in the environment and can be transported from soil to surface and groundwater, where it can accumulate to concentrations above current legal limits . As a result , strict restrictions have been imposed at the regulatory level , particularly in Europe , on the use of herbicide products containing terbuthylazine , such as limiting the use of terbuthylazine to once every three years on the same area of land, with a maximum application rate of 850 g of terbuthylazine per hectare . It is clear that further likely regulatory restrictions or even a ban on the use of terbuthylazine , which might be decided by regulatory authorities in the future , would certainly help to protect the environment , but at the same time deprive farmers of a large number of herbicide formulations , making weed management of many agricultural crops very di f ficult .

[0010] As for metamitron, it is a triazine herbicide used for the control of dicotyledonous weeds in beet crops .

[0011] A few documents , such as EP3884778 , WO2023248223 , CN110754481 , and CN102396468 , describe the use of a combination of herbicides for weed control in various types of crops , wherein metamitron can be used in combination with at least one other herbicide .

[0012] In view of the above state of the art, there is therefore a need to find alternative technical solutions to terbuthylazine to control weeds in an agricultural crop .

[0013] Summary of the invention

[0014] Thus , the obj ect of the present invention is to overcome the drawbacks highlighted above that plague the methods for controlling weeds known in the state of the art , especially the control methods based on the use of terbuthylazine and other triazine products whose use is limited by strict regulatory restrictions .

[0015] Within this general purpose , a speci fic obj ect of the present invention is to provide a method for controlling weeds in which further herbicides , preferably selective ones and having a broad spectrum of action, are used as an alternative to those used in the methods of the known art , particularly as an alternative to terbuthylazine .

[0016] It has now been found that the above and other obj ects , which will be better explained in the following description, can be achieved by using the active ingredient metamitron as a selective herbicide in a number of agricultural crops other than beet. In fact, it was surprisingly found that metamitron can effectively control weed growth in agricultural crops of corn, cotton, sunflower, wheat and many others. The control action is exerted by metamitron when used as the sole selective herbicide or in an agronomic composition as the main herbicide, where "main herbicide" means that metamitron is present in the agronomic composition in a ratio by weight to each other phytosanitary active ingredient, particularly each other herbicidally active ingredient, that is greater than 1:1, preferably equal to or greater than 2:1, even more preferably equal to or greater than 5:1.

[0017] Metamitron has a broad spectrum of action, highly comparable and sometimes superior to that of terbuthylazine, and is therefore able to effectively control a large number of weeds. In particular, some of the weeds on which metamitron is particularly effective are: Solanum nigrum, Amaranthus spp, Capsella bursapastoris, Matricaria chamomilla, Stellaria media, Poligonum aviculare, Chenopodium album, Papaver rhoeas, Fallopia convolvulus , Persicaria maculosa, Veronica persica, Viola arvensis . Metamitron can be used as a sole herbicide or in combination with other herbicides known in the state of the art. The term "sole herbicide" means that metamitron is the only active ingredient with herbicidal action used to control a weed and that no other herbicide is used in combination with metamitron, either in the same agronomic composition or another agronomic composition applied separately or in an extemporaneous mixture .

[0018] Compared with terbuthylazine , metamitron has the advantage of having a toxicological and ecotoxicological profile that is signi ficantly better and in line with current regulatory standards . The improved toxicological and ecotoxicological profile together with its high selectivity, i . e . , the level of tolerance by the useful crops , allow metamitron to be used in higher quantities than terbuthylazine ( e . g . , up to a total annual quantity of 4 , 200 g / ha ) with consequent advantages in terms of herbicidal ef ficacy . It was also observed that the herbicidal ef fect of metamitron is higher if the total annual quantity to be applied of metamitron is subdivided into a number of successive pre-emergence and post-emergence applications on the same crop during the year, the annual number of applications being variable depending on the useful crop and the weed to be controlled . Overall , therefore , metamitron of fers greater application flexibility than other triazine herbicides known in the state of the art , particularly compared to terbuthylazine . In addition, the formulations containing metamitron have lower toxicological , ecotoxicological and environmental impacts , both when metamitron is used as the sole herbicide and when it is used in combination with other co- formulating active ingredients .

[0019] The toxicological and ecotoxicological profiles of metamitron and terbuthylazine are reported in Table 1 below .

[0020] Table 1

[0021] In addition, the application of metamitron, as the sole herbicide , for pre-emergence applications in the listed crops (phenological stage BBCH 00 - BBCH 09 ) and / or post-emergence applications of the same crops (phenological stage BBCH 10 - BBCH 18) and within phonological stage BBCH 13 of the weeds, has been surprisingly shown to advantageously enable substantial elimination of the susceptible weeds.

[0022] In accordance with a first aspect, therefore, the present invention concerns a method for controlling a weed in an agricultural crop, comprising applying an effective herbicidal dose of metamitron to the weed or the locus of the weed, or to the agricultural crop or the locus of the agricultural crop, wherein said agricultural crop is selected from: cereals : wheat, sorghum, corn, rice, barley, oats, rye, spelt, triticale, hops;

[0023] - horticultural crops: solanaceae (e.g., tomatoes, potatoes) , cucurbitaceae (e.g., zucchini cucumbers) , strawberries, blueberries, currants, raspberries, onions, shallots, garlic, carrots, cauliflower, cabbage ; tree crops : pome fruit, stone fruit, citrus fruit, wine grapevine, table grapevine, actinidia, olive tree, banana, coffee, avocado, almond tree, pistachio tree, hazelnut tree, and walnut tree; other crops : lentils, chickpeas, lupins, rapeseed, canola, sugar cane, oil palms, sunflower, soya, cotton, flax, hemp;

[0024] - meadows (e.g., football fields, golf courses, tennis courts, parks, gardens) .

[0025] In a preferred embodiment, the present invention concerns a method for controlling a weed in an agricultural crop comprising applying one or more effective herbicide doses of metamitron to the weed or the locus of the weed, or to the agricultural crop or the locus of the agricultural crop, wherein said agricultural crop is selected from:

[0026] - cereals: wheat, sorghum, corn, rice, barley, oats, rye, spelt, triticale, hops; horticultural crops: solanaceae, cucurbitaceae, strawberries, blueberries, currants, raspberries, onion, shallots, garlic, carrot, cauliflower, cabbage;

[0027] - tree crops: pome fruit, stone fruit, citrus fruit, wine grapevine, table grapevine, actinidia, olive tree, banana, coffee, avocado, almond tree, pistachio tree, hazelnut tree and walnut tree;

[0028] - other crops: lentils, chickpeas, lupins, rapeseed, canola, sugar cane, oil palms, sunflower, soya, cotton, flax, hemp;

[0029] - meadows, wherein metamitron is used as the sole herbicide, wherein metamitron is applied within the phenological stage BBCH 13 of the weed.

[0030] In another preferred embodiment, the present invention concerns a method for controlling a weed in an agricultural crop comprising applying one or more effective herbicide doses of metamitron to the weed or the locus of the weed, or to the agricultural crop or the locus of the agricultural crop, wherein said agricultural crop is selected from:

[0031] - cereals: wheat, sorghum, corn, rice, barley, oats, rye, spelt, triticale, hops; horticultural crops: solanaceae, cucurbitaceae, strawberries, blueberries, currants, raspberries, onion, shallots, garlic, carrot, cauliflower, cabbage;

[0032] - tree crops: pome fruit, stone fruit, citrus fruit, wine grapevine, table grapevine, actinidia, olive tree, banana, coffee, avocado, almond tree, pistachio tree, hazelnut tree and walnut tree;

[0033] - other crops: lentils, chickpeas, lupins, rapeseed, canola, sugar cane, oil palms, sunflower, soya, cotton, flax, hemp;

[0034] - meadows, wherein metamitron is used in combination with an herbicide selected from: 2,4-d, aclonifen, amidosulfuron, bef lubutamid, bensulfuron methyl, bentazone, bifenox, chlorotoluron, clethodim, clodinafop, clomazone, clopyralid, dicamba, dif luf enican, dimethenamid-p, f lazasulfuron, f lorpyrauxif en benzyl, flufenacet, fluometuron, fluroxypyr, glyphosate, imazamox, isoxaf lutole, lenacil, mecoprop, mecoprop-p, mesotrione, metobromuron, napropamide, nicosulfuron, oxyfluorfen, pelargonic acid, propyzamide, prosulfocarb, prosulfuron, pyraf luf en-ethyl, pyridate, pyrithiobac sodium, pyroxsulam, rimsulfuron, sulcotrione, sulfosulfuron, and tribenuron, wherein metamitron is applied within the phenological stage BBCH 13 of the weed .

[0035] According to the latter embodiment of the invention, said herbicide is preferably selected from: 2,4-d, aclonifen, clethodim, dicamba, dimethenamid-p, lenacil, mesotrione, nicosulfuron, pelargonic acid, and rimsulfuron .

[0036] The term "herbicide" is used herein to refer to a compound that controls or modifies the growth of a plant. The term "effective herbicide dose" means the quantity of herbicidally active ingredient (e.g., metamitron) or agronomic composition containing the herbicidally active ingredient that is capable of producing a controlling or growth-modifying effect on a plant. The control or modification effects include any deviation from the natural development of a plant, for example: death, growth retardation, leaf desiccation, albinism, dwarfism, and the like. The term "plant" refers to any physical part of the plant, including seeds, seedlings for transplanting, shoots, roots, tubers, stems, trunks, foliage, flowers, and fruits. The term "site" (locus') includes soil, seeds, seedlings, perennials as well as the areas where weeds are already growing, areas where weeds have yet to emerge, and areas of growing agricultural crops. The "cultivation areas" include the lands on which the agricultural crops are already growing and the lands intended to be cultivated with such agricultural crops.

[0037] The term "weed" is used herein to refer to any unwanted plant and thus includes not only the weeds of agronomic importance described here but also the wild cultivable plants.

[0038] Metamitron, i.e. the compound 4-amino-3-methyl-6- phenyl-1 , 2 , 4-triazin-5 ( 4H) -one, has the following structural formula:

[0039] Metamitron can be prepared with the methods known to the person skilled in the art and is available commercially (e.g., under the trade name Vextamitron®, Vextachem Sri, Italy) .

[0040] Metamitron can be used to control the growth of both monocotyledonous (also called "narrow-leaved" or grasses) and dicotyledonous (broad-leaved) weeds in monocotyledonous or dicotyledonous agricultural crops.

[0041] In an embodiment, preferably, metamitron is used to control dicotyledonous weeds.

[0042] In another embodiment, metamitron is used to control monocotyledonous weeds. In fact, metamitron has been found to effectively limit also the development of monocotyledonous weeds.

[0043] In an embodiment, preferably, metamitron is used to control dicotyledonous and / or monocotyledonous weeds in dicotyledonous agricultural crops.

[0044] In an embodiment, preferably metamitron is used to control dicotyledonous and / or monocotyledonous weeds in monocotyledonous agricultural crops.

[0045] For example, metamitron can be used to control the weed Solanum nigrum (dicotyledon) in a corn crop (monocotyledon) or the weed Digitaria sanguinalis (monocotyledon) in a cotton crop (dicotyledon) . Metamitron is used to control the weeds in the following agricultural crops: cereals : wheat, sorghum, corn, rice, barley, oats, rye, spelt, triticale, hops;

[0046] - horticultural crops: solanaceae (e.g., tomatoes, potatoes) , cucurbitaceae (e.g., zucchini cucumbers) , strawberries, blueberries, currants, raspberries, onions, shallots, garlic, carrots, cauliflower, cabbage ; tree crops : pome fruit, stone fruit, citrus fruit, wine grapevine, table grapevine, actinidia, olive tree, banana, coffee, avocado, almond tree, pistachio tree, hazelnut tree, and walnut tree; other crops : lentils, chickpeas, lupins, rapeseed, canola, sugar cane, oil palms, sunflower, soya, cotton, flax, hemp;

[0047] - meadows (e.g., football fields, golf courses, tennis courts, parks, gardens) .

[0048] Preferably, metamitron is used to control the weeds in the following agricultural crops: cereals : wheat, sorghum, corn, rice, barley, oats, triticale, hops;

[0049] - horticultural crops: solanaceae, cucurbitaceae, blueberries, onions, garlic, cabbage; tree crops : wine grapevine, table grapevine, olive tree;

[0050] - other crops : rapeseed, canola, sunflower, soya, cotton, flax.

[0051] Even more preferably, metamitron is used to control weeds in the following agricultural crops: corn, wheat, sunflower, cotton, rapeseed.

[0052] Preferably, the weeds controlled by the method according to the present invention are:

[0053] Amaranthaceae : Amaranthus spp. , Amaranthus retro flexus , Chenopodium spp. , Chenopodium hybridus , Chenopodium polyspermum, Chenopodium album , Atriplex pa tula;

[0054] Asteraceae : Ambrosia artemisii folia , Ambrosia trifida, Centaurea cyanus, Senecio vulgaris , Hypochaeris spp. , Galinsoga parvi flora , Galinsoga ciliata , Matricaria spp. , Matricaria discoidea , Matricaria chamomilla (Matricaria recutita) , Matricaria maritima , Matricaria inodora (Tripleurospermum inodorum) , Xanthium strumarium, Heliantus annuus, Glebionis segetum, Sonchus asper , Sonchus arvensis , Sonchus oleraceus , Lapsana communis , Cirsium arvense ;

[0055] Apiaceae : Ammi ma jus Aethusa cynapium;

[0056] Primulaceae : Anagallis arvensis ;

[0057] Lamiaceae : Lamium purpureum, Lamium album, Lamium amplexicaule , Stachys annua, Galeopsis tetrahit ;

[0058] Plantaginaceae : Linaria arvensis , Veronica spp. , Veronica arvensism, Veronica persica , Veronica heder i folia;

[0059] Caryophyllaceae : Stellaria media;

[0060] Portulacaceae : Portulaca oleracea ;

[0061] Euphorbiaceae : Mercurialis annua;

[0062] Solanaceae : Solanum nigrum, Datura stramonium,

[0063] Convolvulaceae , Convolvulus spp. , Convolvulus arvensis ;

[0064] Polygonaceae : Persicaria maculosa (Polygonum lapathi folium) , Polygonum convolvulus (Fallopia convolvulus) , Polygonum aviculare, Rumex acetosella ;

[0065] Papaveraceae : Rumania spp. , Rumania officinalis , Papaven spp. , Papaven nhoeas;

[0066] Rubiaceae : Galium apanine ;

[0067] Violaceae: Viola anvensis ;

[0068] Geraniaceae : Genanium spp. , Genanium pusilium;

[0069] Malvaceae : Abutilon theophnasti, Hibiscus tnionum;

[0070] Urticaceae : Untica unens ;

[0071] Fabaceae : Tni folium spp. ;

[0072] Euphorbiaceae : Ruphonbia helioscopia ;

[0073] Brassicaceae : Sinapis anvensis , Capsella spp. ,

[0074] Capsella bunsa-pastonis , Bnassica nigna, Bnassica napus, Diplotaxis enucoides , Raphanus naphanistnum, Thlaspi anvense ;

[0075] Equisetaceae ; Equisetum anvense ;

[0076] Poaceae: Hchinochloa cnus-galli, Setania spp. , Setania glauca, Setania vinidis , Sentania venticillata , Panicum spp. , Panicum miliaceum, Digitania sanguinalis, Poa annua, Songhum halepense , Agnostis spp. , Alopecunus myosunoides , Poa tnivialis , Alopecunus pnatensis , Blymus repens .

[0077] More preferably, the weeds controlled by metamitron are: Solanum nignum, Amananthus spp, Capsella bunsapastonis, Matnicania chamomilla, Stellania media, Poligonum aviculane, Chenopodium album, Papaven nhoeas, Pensicania maculosa, Venonica pension) and Viola anvensis . In a preferred embodiment, said weed is selected from: Solanum nignum, Capsella bunsapastonis , Matnicania chamomilla , Stellania media, Polygonum aviculane , Papaven nhoeas, Pensicania maculosa , Veronica persica and Viola arvensis .

[0078] The application of metamitron in accordance with the present invention enables substantial elimination of the weeds. Preferably, the application of metamitron is made within the early growth stages (2-3 leaves) of the weeds, that is within the phenological stage BBCH 13. In the event that metamitron is applied together with another herbicide, the application of the second herbicide also preferably occurs within the BBCH 13 phenological stage of the weeds.

[0079] For BBCH (Biologische Bundesanstalt , Bundessortenamt and CHemical industry) is intended a known phenological scale indicating the stage of plant development. In the context of the present invention, for BBCH 13 is intended a stage of plant development up to a maximum of 3 leaves.

[0080] Metamitron can be used as a herbicide in an unmodified form, i.e. as obtained by synthesis, but it is generally formulated in agronomic compositions (formulations) using phytopharmacologically acceptable formulation adjuvants, such as vehicles, solvents, and surfactants .

[0081] In accordance with the present invention, the agronomic compositions thus comprise metamitron, at least one formulation adjuvant, and optionally at least one further phytosanitary active ingredient, preferably at least one herbicidally active ingredient.

[0082] The agronomic compositions can be in various physical forms, e.g., dry powders, gels, wettable powders, water-dispersible granules, water-dispersible tablets, effervescent pellets, emulsifiable concentrates, microemulsif iable concentrates, oil-in- water emulsions, oily fluids, aqueous dispersions, oil dispersions, emulsion suspensions, capsule suspensions, emulsifiable granules, soluble liquids, water-soluble concentrates, or in other known forms.

[0083] The agronomic compositions can be prepared with the known methods commonly used in the state of the art. The agronomic compositions, for example, can be prepared by mixing metamitron with the formulation adjuvants to obtain compositions having one of the above forms .

[0084] The agronomic compositions can be used directly or diluted before use. The dilutions can be made, for example, with water, liquid fertilizers, micronutrients, biological organisms, oil or solvents.

[0085] The formulation adjuvants suitable for the preparation of the compositions according to the invention are per se known. As liquid vehicles can be used, for example: water, toluene, xylene, petroleum ether, vegetable oils, acetone, methyl ethyl ketone, cyclohexanone, acid anhydrides, acetonitrile, acetophenone, amyl acetate, 2-butanone, butylene carbonate, chlorobenzene, cyclohexane, cyclohexanol, alkyl esters of the acetic acid, diacetone alcohol, 1 , 2-dichloropropane, diethanolamine, p-diethylbenzene, diethylene glycol, diethylene glycol abietate, diethylene glycol butyl ether, diethylene glycol ethyl ether, diethylene glycolemethyl ether, N,N- dimethylformamide, dimethyl sulfoxide, 1,4-dioxane, dipropylene glycol, dipropylene glycol methyl ether, dipropylene glycol dibenzoate, diproxitol, alkylpyrrolidone, ethyl acetate, 2-ethylhexanol , ethylene carbonate, 1 , 1 , 1-trichloroethane, 2-heptanone, alpha-pinene, d-limonene, ethyl lactate, ethylene glycol, ethylene glycol butyl ether, ethylene glycol methyl ether, gamma-butyrolactone, glycerol, glycerol acetate, glycerol diacetate, glycerol triacetate, hexadecane, hexylene glycol, isoamyl acetate, isobornyl acetate, isooctane, isophorone, isopropylbenzene, isopropylmyristate, lactic acid, laurylamine, mesityloxide, methoxypropanol, methyl isoamyl ketone, methyl isobutyl ketone, methyl laurate, methyl octanoate, methyl oleate, methylene chloride, m-xylene, n-hexane, n-octylamine, octadecanoic acid, octylamine acetate, oleic acid, oleylamine, o-xylene, phenol, polyethylene glycol (PEG400) , propionic acid, propyl lactate, propylene carbonate, propylene glycol, propylene glycol methyl ether, p-xylene, toluene, triethylphosphate, triethylene glycol, xylenesulfonic acid, kerosene, mineral oil, trichloroethylene, perchloroethylene, ethyl acetate, amyl acetate, butyl acetate, propylene glycol methyl ether, diethylene glycol methyl ether, methanol, ethanol, isopropanol, and higher molecular weight alcohols.

[0086] Nonionic, anionic or cationic surfactants of the type known to the person skilled in the art can be used as surfactant substances.

[0087] The agronomic compositions generally comprise from 0.1% to 99% by weight, preferably from 0.1% to 95% by weight, of metamitron and from 1% to 99.9% by weight, preferably from 99.9% to 5% by weight, of formulation adjuvants. The commercial products are preferably formulated as concentrates, although the end user normally uses diluted formulations.

[0088] In accordance with an embodiment of the present invention, metamitron can be the only herbicidally active ingredient applied. In accordance with another embodiment, metamitron can also be used in combination with other phytosanitary active ingredients. In particular, metamitron can be used in combination with further herbicides to achieve an agronomic composition having a broader spectrum of herbicidal action.

[0089] Examples of further phytosanitary active ingredients that can be used in combination with metamitron are: acaricides, bactericides, fungicides, insecticides, algaecides, molluscicides, nematocides, rodenticides, phytoregulators, repellents, semiochemicals , virucides, pesticides, geodisinfectants, soil improvers and fertilizers.

[0090] Preferably, the weight ratio between metamitron and each further phytosanitary active ingredient other than metamitron is within the range from 1:100 to 1,000:1, more preferably from 1:10 to 100:1.

[0091] The further phytosanitary active ingredients can be mixed with metamitron in a same formulation, which can be used, for example, by the end user as such or after dilution, or they can be combined together in an extemporaneous mixture (tank mix) , for example, prepared by the end user at the time of application. The further phytosanitary active ingredients can be used in combination with metamitron both simultaneously (applied separately through separate agronomic compositions or applied together in a single agronomic composition) and sequentially.

[0092] When metamitron is used in combination with at least one further herbicide, the preferred combinations are those including metamitron and one or more of the following herbicides: acetyl-CoA carboxylase (ACCase) enzyme inhibitors (HRAC group A) , acetolactate synthetase (ALS) enzyme inhibitors (HRAC group B) , photosystem II (PS II) inhibitors (HRAC groups Cl, C2 and C3) , photosystem I (PS I) inhibitors (HRAC group D) , protoporphyrinogen oxidase (PPO) inhibitors (HRAC group E) , 4-hydroxyphenyl pyruvate-dioxygenase (HPPD) inhibitors (HRAC group Fl) , phytoene desaturase (PDS) inhibitors (HRAC group F2 ) , carotenoid biosynthesis inhibitors (HRAC group F3) , DOXP synthase inhibitors (HRAC group F4 ) , 5-enolpimvilshikimate-3-phosphate (EPSP) inhibitors (HRAC group G) , inhibitors of glutamine synthetase (HRAC Group H) , inhibitors of DHP synthase (HRAC Group I) , inhibitors of microtubule assembly (HRAC Group KI) , inhibitors of microtubule mitosis / organization (HRAC Group K2 ) , inhibitors of very long chain fatty acid (VLCFA) (HRAC Group K3) , cell wall synthesis inhibitors (HRAC Group L) , uncoupling (membrane disruption) (HRAC Group M) , lipid synthesis inhibitors (HRAC Group N) , synthetic auxins (HRAC Group 0) , auxin transport inhibitors (HRAC Group P) and herbicides with unknown mode of action (HRAC Group Z) .

[0093] When metamitron is used in combination with at least one further herbicide, the preferred combinations are those including metamitron and one or more of the following herbicides: 2,4-d, acetochlor, aclonifen, alachlor, amidosulfuron, atrazine, bef lubutamid, bensulfuron methyl, bentazone, bifenox, bromofenoxim, bromoxynyl octanoate, chlorotoluron, chlorpropham, clethodim, clodinafop, clomazone, clopyralid, cycloxydim, dalapon, dicamba, dichlobenil, dichlormid, dichlof op-methyl , dif luf enican, dimethenamid-p, diuron, f lazasulfuron, florasulam, f lorpyrauxif en benzyl, f luazifop-p-butyl, flufenacet, fluroxypyr, furilazole, glyphosate, imazamox, isoxaf lutole, lenacil, linuron, mecoprop, mecoprop-p, mesotrione, metazachlor, metobromuron, metolachlor, metribuzin, napropamide, nicosulfuron, oxyfluorfen, pelargonic acid, pendimethalin, penoxsulam, pethoxamid, phenmedipham, profoxydim, propachlor, propaquizafop, propyzamide, prosulfocarb, prosulfuron, pyraf luf en-ethyl , pyridate, pyrithiobac sodium, pyroxsulam, quizalofop-p-ethyl, quizalofop-p-tefuryl, rimsulfuron, secbumeton, simazine, s-metolachlor , sulcotrione, sulfosulfuron, terbumeton, terbuthylazine, tri-allate, and tribenuron.

[0094] Particularly preferred are the following combinations :

[0095] • metamitron + pendimethalin;

[0096] • metamitron + dimethanamid-P;

[0097] • metamitron + fluometuron; metamitron + clomazone; metamitron + clethodim;

[0098] • metamitron + mesotrione;

[0099] • metamitron + S-metholachlor;

[0100] • metamitron + tembotrione;

[0101] • metamitron + clopyralid olamine;

[0102] • metamitron + cyprosulfamide;

[0103] • metamitron + thiencarbazone ;

[0104] • metamitron + pelargonic acid;

[0105] • methamitron + caprylic acid;

[0106] • metamitron + fluometuron + terbuthylazine

[0107] • metamitron + dimethanamid-P + clomazone;

[0108] • metamitron + S-metholachlor + mesotrione.

[0109] Even more preferred are the following combinations:

[0110] • metamitron + dimethanamid-P;

[0111] • metamitron + fluometuron;

[0112] • metamitron + clomazone;

[0113] • metamitron + clethodim;

[0114] • metamitron + mesotrione;

[0115] • metamitron + pelargonic acid;

[0116] • metamitron + pyrithiobac sodium.

[0117] The above combinations optionally comprise a further phytosanitary active ingredient, such as a further herbicidally active ingredient.

[0118] The weight ratio of metamitron to each further herbicide is preferably within the range from 1:100 to 1,000:1, more preferably from 1:10 to 100:1.

[0119] In accordance with the present invention, metamitron is applied to one or more of the following targets : weed, locus of the weed, agricultural crop and locus of the agricultural crop . The application can only be made to one or more of the above targets or to a combination of them . The application can also be made simultaneously or sequentially to two or more of the above targets .

[0120] Metamitron can be applied before or after sowing the agricultural crop, before the emergence of the agricultural crop (pre-emergence ) or after the emergence of the agricultural crop (post-emergence ) .

[0121] Preferably, metamitron is applied within the cotyledonary stage of the weed ( i . e . , within BBCH 13 ) .

[0122] When metamitron is applied after the emergence of the agricultural crop, preferably it is applied within the phenological stage BBCH 18 of the agricultural crop .

[0123] The quantity of metamitron applicable to control a weed on an agricultural crop can vary over a wide range . In general , metamitron can be applied in an quantity from 0 . 1 to 10 kg / ha, preferably from 350 to 5 , 000 g / ha . Preferably, the above quantities are applied over one year .

[0124] Preferably, metamitron is applied on the same hectare of land in a maximum annual quantity of 4 , 200 g / ha, more preferably in an annual quantity within the range from 350 g / ha to 4 , 200 kg / ha .

[0125] The dosage for pre-emergence and post-emergence applications is a function of the nature of the land, the level of infestation, and whether further herbicides or other phytosanitary active ingredients are used in addition to metamitron .

[0126] Preferably, the number of annual applications of metamitron on the same hectare of land is within the range from 1 to 6 , more preferably from 1 to 5 , even more preferably from 1 to 3 .

[0127] Preferably, the dose of metamitron of a single application (pre-emergence or post-emergence ) is within the range 350 - 2 , 800 g / ha, more preferably 700 - 1 , 400 g / ha .

[0128] In an embodiment , metamitron is applied twice a year, preferably under the following conditions : make a pre-emergence application at a phenological stage of the agricultural crop within the range BBCH 0 - 9 , when the weeds have not yet emerged;

[0129] - make a post-emergence application within the phenological stage BBCH 15 of the agricultural crop, when the weeds have developed up to a maximum of 3 leaves (BBCH 13 ) .

[0130] I f weed control is insuf ficient after the above two applications , a third post-emergence application can optionally be made within the phenological stage BBCH 18 of the agricultural crop, when the weeds have developed up to a maximum of 3 leaves (BBCH 13 ) .

[0131] The mode of application of metamitron may vary from case to case based on the type of agricultural crop and weed .

[0132] Based on the type of weeds to be controlled, the maximum quantity of 4 , 200 g / ha per year of metamitron can be distributed in a number of applications within the range from 1 to 6 applications / year on the same hectare .

[0133] Some examples of possible ways of applying metamitron according to the present invention are described below .

[0134] When the method according to the invention is carried out at a regime of one application / year , preferably metamitron is applied at a dose of 350 g / ha - 4 , 200 g / ha before the emergence of the agricultural crop or after the emergence of the agricultural crop up to the phenological stage BBCH 18 of the agricultural crop .

[0135] When the method according to the invention is carried out at a regimen of two or three applications / year, preferably metamitron is applied at a dose of 700 - 2 , 100 g / ha before the emergence of the agricultural crop followed by a dose of 700 - 2 , 100 g / ha after the emergence of the agricultural crop up to the phenological stage BBCH 18 of the agricultural crop . In the case of prolonged weed germination, the two pre- and post-emergence treatments previously described can be followed by a further application of metamitron at a dose of 700 - 2 , 100 g / ha within the stage BBCH 18 of the agricultural crop .

[0136] In another embodiment , the total dose of 4 . 2 kg / ha per year of metamitron can be applied exclusively postemergence up to the phenological stage BBCH 18 of the agricultural crop, preferably through two or more applications . Preferably, the applications are made after the emergence of the agricultural crop and within the cotyledon stage of the weed that germinates as first, preferably at a dose of 700 - 2,100 g / ha of metamitron. The treatment can be repeated whenever a new weed germinates and reaches the cotyledon stage up to the stage BBCH 18 of the agricultural crop. If after 7 to 10 days after the first application the weeds survive, it is preferable to make a further application at a dose of 700 - 2,100 g / ha even if no new weeds have germinated in that time frame.

[0137] Some examples of application protocols, in relation to the type of agricultural crop, dosage of the formulation (1 / ha of concentrated suspension in water containing 700 g / 1 of metamitron) , number of annual applications and time of use is reported in Table 2 below .

[0138] Table 2 - Example of application protocols of metamitron only

[0139]

[0140] The dosages and concentrations of the formulations , the dosages of active ingredient per hectare and the number of applications per year reported in Table 2 are examples of how the present invention can be implemented and may be varied depending on the type of weed, agricultural crop and level of infestation .

[0141] The application of metamitron or an herbicide composition containing it to the weeds , agricultural crop, or relative sites can be done by any of the common application methods used in agriculture , such as using the common equipment for distributing phytosanitary products , including overhead irrigation systems and spray apparatuses .

[0142] To improve the herbicidal ef ficacy of metamitron and its selectivity toward useful crops , when used alone or in combination with other phytosanitary active ingredients , it is preferable to perform one or more of the following operations :

[0143] ( a ) prepare the seedbed so as to operate on perfectly level and clod- free soil , preferably moist , also providing for irrigation ( about 10 mm of water ) i f rain does not occur within 7 to 10 days after the application of metamitron so as to promote penetration of the product into the surface layer of soil ;

[0144] (b ) sow the agricultural crop evenly and regularly at a depth of at least 2-5 cm;

[0145] ( c ) to complete the spectrum of action on the weeds , apply metamitron in combination with other herbicides . The present invention will now be described in more detail by means of the following embodiment examples , which are not to be understood as limiting the scope of protection defined by the appended claims . EXAMPLE 1 Experimental field trials were conducted to validate the ef ficacy of the present invention on agricultural crops of Corn, Cotton, Sunflower and Wheat . The trials were conducted in GEP ( Good Experimental Practice ) accredited experimental centres in the four main climate zones defined by EPPO (European and Mediterranean Plant Protection Organi zation) .

[0146] In each trial , a concentrated suspension ( SC ) of metamitron ( 700 g / L concentration) was applied, after dilution with water, alone or in combination with other herbicidally active ingredients , under the conditions illustrated in Tables 3 - 6 below .

[0147] The further herbicidally active ingredients were either added to the concentrated suspension containing metamitron, where present , or prepared in separate formulations as concentrated suspensions .

[0148] In the examples , ef ficacy against dicotyledonous (broad-leaved) and monocotyledonous (narrow-leaved) weeds indicated in Tables 3- 6 was evaluated, where the following abbreviations were used : AMARE = Amaran thus retro fl exus , AMAVI = Amaranthus viridi s, SONOL = Sonchus ol eraceus ; DIGSA (monocotyledo ) = Digi taria sanguinali s, POROL = Portulaca oleracea, SOLNI = Solanum nigrum, CHEAL = Chenopodi um album, SPRAR = Spergula arvensis, CONAR = Convolvulus arvensis , AMBSS = Ambrosia sp. , ABUTH = Abutilon theophrasti, CYPRO = Cyperus rotundus , ECHGL = Echinochloa glabrescens , AMABL = Amaranthus blitoides , GALAP = Galium aparine, STAAR = Stachys arvensis , MATCH = Matricaria chamomilla, CIRAR = Cirsium arvense , VERPE = Veronica persica , PAPRH = Papaver rhoeas and PHASS = Phalaris .

[0149] The following parameters were determined in the trials : - phytotoxicity (0% = no crop damage; 100% dead crop) ;

[0150] - vigor compared to untreated control (0% = crop development interruption; 100% regular crop development) ; - efficacy (0% = weed with regular development;

[0151] 100% = dead weed) ; the efficacy values reported in the tables are average values calculated on the basis of five trials.

[0152] Table 3 - Herbicidal efficacy of a concentrated suspension containing metamitron (700 g / L active ingredient) on corn

[0153]

[0154] * comparative example

[0155] 1monocotyledonous weed

[0156] 2p.i. : phytosanitary active ingredient

[0157] The data of Table 3 show that metamitron applied alone , once or more times , or in combination with the other herbicides reported in the table can ef fectively control all dicotyledonous weeds . Regarding the monocotyledon weed Digi taria sanguinali s ( DIGSA) , the data show that an ef fective control can be achieved by a combination of a pre-emergence and a post-emergence application or with the aid of a second herbicide in the case of lower dosages or of a single application .

[0158] Table 4 - Herbicidal efficacy of a concentrated suspension containing metamitron (700 g / L active ingredient) on cotton

[0159]

[0160] * comparative example

[0161] 1monocotyledonous weed

[0162] 2p.i. : phytosanitary active ingredient

[0163] The data of Table 4 show that metamitron alone or in combination with a further herbicide selected from Pendimethalin, Dimethenamid P and Clethodim ef fectively controlled all the weeds present in the trial , both when applied in pre-emergence and applied in postemergence , demonstrating ef ficacy comparable to that of the agronomic composition of the prior art represented by a mixture of Terbuthylazine and Pendimethanil .

[0164] Table 5 - Herbicidal efficacy of a concentrated suspension containing metamitron (700 g / L active ingredient) on sunflower

[0165] * comparative example

[0166] 1p.i. : phytosanitary active ingredient

[0167] The data of Table 5 show that metamitron alone ef fectively reduced the development of dicotyledonous weeds present in the trial . In combination with Pendimethalin (pre-emergence application) and Acloni fen (post-emergence application) , it ef fectively controlled all weeds present in the trial .

[0168] Table 6 - Herbicidal efficacy of a concentrated suspension containing metamitron (700 g / L active ingredient) on wheat

[0169]

[0170] 1monocotyledonous weed

[0171] 2p.i. : phytosanitary active ingredient

[0172] The data of Table 6 refer to field trials in which dicotyledonous weeds developed . The data show that metamitron alone ef fectively reduced the development of weeds present in the trial . In combination with Clortoluron (pre-emergence application) or in combination with Pendimethalin, Di f luf enican, Pinoxaden + Clodinafop propargyl (pre-emergence or post-emergence application) , it ef fectively controlled all weeds present in the trial .

Claims

CLAIMS1) Method for controlling a weed in an agricultural crop comprising applying one or more effective herbicidal doses of metamitron to the weed or the locus of the weed, or to the agricultural crop or the locus of the agricultural crop, wherein said agricultural crop is selected from: cereals: wheat, sorghum, corn, rice, barley, oats, rye, spelt, triticale, hops;- horticultural crops: solanaceae, cucurbitaceae, strawberries, blueberries, currants, raspberries, onion, shallots, garlic, carrot, cauliflower, cabbage; tree crops: pome fruit, stone fruit, citrus fruit, wine grapevine, table grapevine, actinidia, olive tree, banana, coffee, avocado, almond tree, pistachio tree, hazelnut tree and walnut tree; other crops: lentils, chickpeas, lupins, rapeseed, canola, sugar cane, oil palms, sunflower, soya, cotton, flax, hemp;- meadows, wherein metamitron is used as the sole herbicide, wherein metamitron is applied within the phenological stage BBCH 13 of the weed.2) Method for controlling a weed in an agricultural crop comprising applying one or more effective herbicidal doses of metamitron to the weed or the locus of the weed, or to the agricultural crop or the locus of the agricultural crop, wherein said agricultural crop is selected from: cereals: wheat, sorghum, corn, rice, barley,oats, rye, spelt, triticale, hops;- horticultural crops: solanaceae, cucurbitaceae, strawberries, blueberries, currants, raspberries, onion, shallots, garlic, carrot, cauliflower, cabbage; tree crops: pome fruit, stone fruit, citrus fruit, wine grapevine, table grapevine, actinidia, olive tree, banana, coffee, avocado, almond tree, pistachio tree, hazelnut tree and walnut tree; other crops: lentils, chickpeas, lupins, rapeseed, canola, sugar cane, oil palms, sunflower, soya, cotton, flax, hemp;- meadows, wherein metamitron is used in combination with an herbicide selected from: 2,4-d, aclonifen, amidosulfuron, bef lubutamid, bensulfuron methyl, bentazone, bifenox, chlorotoluron, clethodim, clodinafop, clomazone, clopyralid, dicamba, dif luf enican, dimethenamid-p, f lazasulfuron, f lorpyrauxif en benzyl, flufenacet, fluometuron, fluroxypyr, glyphosate, imazamox, isoxaf lutole, lenacil, mecoprop, mecoprop-p, mesotrione, metobromuron, napropamide, nicosulfuron, oxyfluorfen, pelargonic acid, propyzamide, prosulfocarb, prosulfuron, pyraf luf en-ethyl, pyridate, pyrithiobac sodium, pyroxsulam, rimsulfuron, sulcotrione, sulfosulfuron, and tribenuron, wherein metamitron is applied within the phenological stage BBCH 13 of the weed.3) Method according to claim 2, wherein said herbicide is selected from: 2,4-d, aclonifen,clethodim, dicamba, dimethenamid-p, lenacil , mesotrione, nicosulfuron, pelargonic acid, and rimsulfuron .4) Method according to any one of claims 1-3, wherein said agricultural crop is a dicotyledonous agricultural crop.5) Method according to any one of claims 1-4 wherein said agricultural crop is selected from: cereals: wheat, sorghum, corn, rice, barley, oats, triticale, hops;- horticultural crops: solanaceae, cucurbitaceae, blueberries, onion, garlic, cabbage; tree crops: wine grapevine, table grapevine, olive tree; other crops: rapeseed, canola, sunflower, soybean, cotton, flax.6) Method according to claim 5, wherein said agricultural crop is selected from: corn, wheat, sunflower, cotton, rapeseed.7) Method according to any one of claims 1-3, wherein said agricultural crop is a monocotyledonous agricultural crop.8) Method according to any one of claims 1 to 7, wherein the weed is selected from: monocotyledonous weed and dicotyledonous weed, preferably dicotyledonous weed .9) Method according to any one of claims 1 to 8, wherein the weed is selected from:Amaranthaceae : Amaranthus spp.rAmaranthus retro flexus , Chenopodium spp.rChenopodium hybridusrChenopodium polyspermum, Chenopodium album, Atriplex pa tula;Asteraceae : Ambrosia artemisii folia , Ambrosia trifida, Centaurea cyanus, Senecio vulgaris , Hypochaeris spp. , Galinsoga parvi flora , Galinsoga ciliata , Matricaria spp. , Matricaria discoidea , Matricaria chamomilla (Matricaria recutita) , Matricaria maritima , Matricaria inodora (Tripleurospermum inodorum) , Xanthium strumarium, Heliantus annuus, Glebionis segetum, Sonchus asper, Sonchus arvensis , Sonchus oleraceus , Lapsana communis , Cirsium arvense ;Apiaceae : Ammi ma jus, Aethusa cynapium;Primulaceae : Anagallis arvensis ;Lamiaceae : Lamium purpureum, Lamium album, Lamium amplexicaule , Stachys annua, Galeopsis tetrahit ;Plantaginaceae : Linaria arvensis , Veronica spp. , Veronica arvensism, Veronica persica , Veronica heder i folia;Caryophyllaceae : Stellaria media;Portulacaceae : Portulaca oleracea ;Euphorbiaceae : Mercurialis annua;Solanaceae : Solanum nigrum, Datura stramonium,Convolvulaceae , Convolvulus spp. , Convolvulus arvensis ;Polygonaceae : Persicaria maculosa (Polygonum lapathi folium) , Polygonum convolvulus (Fallopia convolvulus) , Polygonum aviculare , Rumex acetosella ;Papaveraceae : Fumaria spp. , Fumaria officinalis , Papaver spp. , Papaver rhoeas;Rubiaceae : Galium aparine ;Violaceae: Viola arvensis ;Geraniaceae : Geranium spp. , Geranium pusilium;Malvaceae : Abutilon theophrasti, Hibiscus trionum;Urticaceae : Urtica urens ;Fabaceae : Tri folium spp. ;Euphorbiaceae : Euphorbia helioscopia ;Brassicaceae : Sinapis arvensis , Capsella spp. ,Capsella bursa-pastoris , Brassica nigra, Brassica napus, Diplotaxis erucoides , Raphanus raphanistrum, Thlaspi arvense ;Equisetaceae ; Equisetum arvense ;Poaceae : Echinochloa crus-galli, Setaria spp. , Setaria glauca, Setaria viridis , Sertaria verticillata , Panicum spp. , Panicum miliaceum, Digitaria sanguinalis, Poa annua, Sorghum halepense , Agrostis spp. , Alopecurus myosuroides , Poa trivialis , Alopecurus pratensis , Elymus repens.10) Method according to claim 9, wherein the weed is selected from: Solanum nigrum, Capsella bursapastoris , Matricaria chamomilla , Stellaria media, Polygonum aviculare , Papaver rhoeas, Persicaria maculosa , Veronica persica and Viola arvensis .11) Method according to any one of claims 1 to 10, wherein metamitron is applied in combination with at least a further phytosanitary active ingredient selected from: acaricides, bactericides, fungicides, insecticides, algaecides, molluscicides, nematocides, rodenticides, phytoregulators, repellents, semiochemicals , virucides, pesticides, geodisinf estants , soil improvers and fertilizers.12) Method according to any one of claims 2 to 11,wherein metamitron is applied in one of the following combinations with a herbicidally active ingredient :• metamitron + dimethanamid-P• metamitron + fluometuron• metamitron + clomazone• metamitron + clethodim• metamitron + mesotrione• metamitron + pyrithiobac sodium• metamitron + pelargonic acid .13 ) Method according to any one of claims 1 to 12 , wherein metamitron is applied in the form of an agronomic composition comprising metamitron, at least one formulation adj uvant , and optionally at least one further phytosanitary active ingredient .14 ) Method according to any one of claims 2 to 13 , wherein metamitron is applied in the form of an agronomic composition said agronomic composition comprising metamitron and at least one phytosanitary active ingredient other than metamitron, preferably a herbicidally active ingredient .15 ) Method according to any one of claims 1 to 14 , wherein metamitron is applied according to one or more of the following methods :( a ) before or after sowing the agricultural crop ;(b ) before the emergence of the agricultural crop ;( c ) after the emergence of the agricultural crop .16 ) Method according to any one of claims 1 to 15 , wherein metamitron is applied before the agricultural crop reaches the phenological stage BBCH 18 .17 ) Method according to any one of claims 1 to 16 ,wherein metamitron is applied from 1 to 6 times per year, preferably from 1 to 5 times per year, even more preferably from 1 to 3 times per year.18) Method according to any one of claims 1 to 17, wherein metamitron is applied in an annual quantity of at most 4,200 g / ha, preferably in an annual quantity within the range 350 - 4,200 g / ha.19) Method according to any one of claims 1 to 18, wherein metamitron is applied in a dose of 350 - 2,800 g / ha, preferably 700 - 1,400 g / ha, for a single application .