Method of controlling, limiting or preventing oomycetes

Abstract

This invention relates to a method of controlling, limiting or preventing an infestation of a plant by Oomycetes, which comprises applying to propagation material of said plant, a pesticidal combination comprising a phosphorus-based compound as active ingredient A, and an active ingredient B selected from acibenzolar-S-methyl, fludioxonil, fluxapyroxad, inpyrfluxam, mefentrifluconazole, prothioconazole, sedaxane, triticonazole, oxathiapiprolin, fluoxapiprolin, azoxystrobin, difenoconazole, fluopyram, ipconazole, metyltetraprole, silthiofam, dimethomorph, thiophanate-methyl, natamycin, benzovindiflupyr, pydiflumetofen, picarbutrazox, isocycloseram, cyclobutrifluram, broflanilide, thiamethoxam, imidacloprid, clothianidin, cyantraniliprole, chlorantraniliprole, tetraniliprole, fipronil, and any mixture thereof.

Description

[0001] METHOD OF CONTROLLING, LIMITING OR PREVENTING OOMYCETES

[0002] This invention relates to a method of controlling, limiting or preventing an infestation of plants by phytopathogenic microorganisms, such as Oomycetes (Oomycota phytopathogens), in treating plant propagation material, and to a seed treatment use.

[0003] Whilst many fungicidal compounds and compositions, belonging to various different chemical classes, have been / are being developed for use as fungicides in crops of useful plants, crop tolerance and activity against particular phytopathogenic fungi do not always satisfy the needs of agricultural practice in many respects, especially as plant propagation material treatment. Therefore, there is a continuing need to find new compounds and compositions having superior biological properties for use in controlling or preventing infestation of plants by phytopathogenic fungi.

[0004] Therefore, the aim of the present invention is to propose new mixtures, and especially new plant propagation material treatments, guaranteeing a good efficacy against phytopathogenic fungi belonging to Oomycetes, and especially achieving a synergistic effect to treat phytopathogenic fungi belonging to Oomycetes.

[0005] To this end, a first object of the present invention relates to a method of controlling, limiting or preventing an infestation of a plant by Oomycetes, which comprises applying to propagation material of said plant, a pesticidal combination comprising a phosphorus-based compound as active ingredient A, and an active ingredient B selected from acibenzolar-S- methyl, fludioxonil, fluxapyroxad, inpyrfluxam, mefentrifluconazole, prothioconazole, sedaxane, triticonazole, oxathiapiprolin, fluoxapiprolin, azoxystrobin, difenoconazole, fluopyram, ipconazole, metyltetraprole, silthiofam, dimethomorph, thiophanate-methyl, natamycin, benzovindiflupyr, pydiflumetofen, picarbutrazox, isocy closeram, cyclobutrifluram, broflanilide, thiamethoxam, imidacloprid, clothianidin, cyantraniliprole, chlorantraniliprole, tetraniliprole, fipronil, and any mixture thereof, and preferably a fungicidally effective amount of active ingredient A and active ingredient B, optionally together with one or more customary formulation adjuvant(s).

[0006] Controlling, limiting or preventing (and its inflections), within the context of the present invention, mean reducing any undesired effect, such as pathogenic, and especially phytopathogenic such as fungi that belong to Oomycetes, infestation or attack of, and pathogenic damage on plant propagation material to such a level that an improvement is demonstrated.

[0007] The method according to the present invention has advantageous properties for protecting plants against pathogenic, such as phytopathogenic, especially Oomycota phytopathogens, attack or infestation, which result in a disease and damage to the plant; particularly in instance of plants, the present invention can control, limit or prevent pathogenic damage on a seed, parts of plant and / or plant grown from the treated seed.

[0008] The method according to the present invention has particularly advantageous levels of biological activity as plant propagation material treatment, against Oomycetes.

[0009] The application of the pesticidal combination can be done in any desired sequence or simultaneously, and preferably simultaneously.

[0010] The phosphorus-based compound according to the present invention can be an oxidized form of phosphorus, such as a phosphonate, and more particularly a phosphonate salt, or phosphonic acid. The phosphonate may preferably include at least one functional group characterized by a phosphorus atom bonded to three oxygen atoms. The term "phosphonate” can also refer to as "phosphite".

[0011] Phosphonate can be made of the salts or esters of phosphorous acid (or phosphonic acid), and can include alkyl phosphonate.

[0012] More particularly, the phosphorus-based compound can be a phosphonate salt, and more particularly a phosphonate salt of potassium, sodium, calcium, aluminium, or ammonium.

[0013] The phosphorus-based compound can be selected from phosphonic acid, phosphonate salts (for example: potassium phosphonates, sodium phosphonates, calcium phosphonates, and / or ammonium phosphonates), other phosphorus-based compounds, and any mixture thereof; and preferably the phosphorus-based compound can be selected from phosphonic acid, one or several phosphonate salts, and any mixture thereof. For example the phosphorus-based compound can be selected from phosphorus pentoxide, dipotassium phosphonate, monopotassium phosphonate, disodium phosphonate, calcium phosphonate, ammonium methyl phosphonate, monoammonium phosphonate, diammonium phosphonate, aluminium tri(ethyl phosphonate), phosphonic acid, and any mixture thereof, and more preferably selected from phosphonic acid, monopotassium phosphite, dipotassium phosphite, diammonium phosphonate, and any mixture thereof. Phosphorus-based compounds can be commercially available products, such as the technical active ingredient, or a formulated product including the active ingredient.

[0014] As the term "phosphonate” can also refer to as "phosphite", the expressions dipotassium phosphonate, monopotassium phosphonate, disodium phosphonate, calcium phosphonate, ammonium methyl phosphonate, monoammonium phosphonate, diammonium phosphonate, and aluminium tri(ethyl phosphonate), can also be understood as dipotassium phosphite, monopotassium phosphite, disodium phosphite, calcium phosphite, ammonium methyl phosphite, monoammonium phosphite, diammonium phosphite, aluminium tri(ethyl phosphite).

[0015] The plant according to the present invention can be selected from vegetables (including brassicas, solanaceous crops, cucurbits, leafy, root, and stem), legume crops, oil crops, beets, fibre plants, and cereals, and preferably from vegetables, legume crops, oil crops and cereals.

[0016] In a particular embodiment, vegetables can be selected from asparagus, eggplant, broccoli, cabbage, cauliflower, carrot, cucumber, garlic, marrow, melon, okra, onion, pepper, potato, pumpkin, rhubarb, spinach, tomato, lettuce, chard, celery, endive, lamb’s lettuce, and rucola. Vegetables can include leafy vegetable selected from lettuce, chard, spinach, celery, endive, lamb’s lettuce, and rucola. The preferred vegetable can be broccoli, cabbage, cauliflower, carrot, pepper, tomato, lettuce, or spinach.

[0017] In another particular embodiment, the legume crop can be selected from beans, lentils, peas, and soya (e.g. soybean). The preferred legume crop can be soybean, peas, or beans.

[0018] In another particular embodiment, the oil crop can be selected from oilseed rape, canola, mustard, poppies, olives, sunflowers, coconut, castor, cocoa, and ground nuts. The preferred oil crop can be oilseed rape, canola, or sunflower.

[0019] In another particular embodiment, the beet can be selected from sugar beet, fodder beet, and red beet.

[0020] In another particular embodiment, the fibre plant can be selected from cotton, flax, hemp, and jute. In another particular embodiment, the cereal can be selected from wheat, barley, rye, oats and maize, maize being the preferred cereal. Maize can be selected from field com, popcorn, com, rice, sorghum and related crops. The preferred cereal can be wheat, rice or maize

[0021] In the present invention, propagation material of a plant can be understood to denote all the generative parts of the plant, such as seeds, which can be used for the multiplication of the latter including vegetative plant material such as cuttings. There may be mentioned, as plant propagation material, seeds (in the strict sense), roots, fruits, tubers, bulbs, rhizomes, parts of plants. The plant propagation material can be treated with the active ingredient(s) of the invention before the material is sown or planted. Alternatively, the plant propagation material may be treated with the active ingredient(s) of the invention during sowing or planting. Additionally, the active ingredient(s) of the invention may be applied to the previously treated propagation material before or during its planting. The active ingredient(s) of the invention may be applied during the sowing of the seed. The active ingredient(s) may also be used to plant propagation material derived from plants grown in a green house and / or during transplantation.

[0022] More preferably the plant propagation material is plant seeds.

[0023] The seed treatment can occur to an unsown seed, and the term "unsown seed" is meant to include seed at any period between the harvest of the seed and the sowing of the seed in the ground for the purpose of germination and growth of the plant. Treatment to an unsown seed is not meant to include those practices in which the pesticide is applied to the soil but would include any application practice that would target the seed during the sowing / planting process.

[0024] The treated plant propagation material of the present invention can be treated in the same manner as conventional plant propagation material. The treated propagation material can be stored, handled, sown and tilled in the same manner as any other pesticide treated material.

[0025] According to the present invention, the active ingredients A and B can be present in a synergistically effective amount in the pesticidal composition.

[0026] In the present invention, the application rate can be from 1 gram to 500 grams of the active ingredient A, preferably from 10 grams to 400 grams of the active ingredient A, preferably from 20 grams to 300 grams of the active ingredient A, preferably from 30 grams to 300 grams of the active ingredient A, and more preferably from 30 grams to 200 grams of the active ingredient A, over 100 kg of plant propagation material.

[0027] The application rate can be from 0.5 gram to 250 grams of the active ingredient B, preferably from 1 gram to 200 grams of the active ingredient B, preferably from 1 gram to 100 grams of the active ingredient B, preferably from 1 gram to 50 grams of the active ingredient B, and more preferably from 1 gram to 30 grams of the active ingredient B, over 100 kg of plant propagation material.

[0028] In a particular embodiment, the application rate of the active ingredient A and of the active ingredient B can be as follows, more preferably on Pythium diseases:

[0029] For example, the following rates can be applied, more preferably on Pythium diseases: In another particular embodiment, the application rate can advantageously comprise a weight ratio of the active ingredient A to the active ingredient B from 1 : 100 to 1000: 1, preferably from 1 : 100 to 400: 1, preferably from 1 : 100 to 100: 1, and more preferably from 1 : 10 to 10: 1.

[0030] In another particular embodiment, the pesticidal combination can comprise a third active ingredient C, different from the selected active ingredient A and from the selected active ingredient B, the active ingredient C being selected from phosphorus pentoxide, dipotassium phosphonate, monopotassium phosphonate, disodium phosphonate, calcium phosphonate, ammonium methyl phosphonate, monoammonium phosphonate, diammonium phosphonate, aluminium tri(ethyl phosphonate), phosphonic acid, acibenzolar-S-methyl, fludioxonil, fluxapyroxad, inpyrfluxam, mefentrifluconazole, prothioconazole, sedaxane, triticonazole, oxathiapiprolin, fluoxapiprolin, azoxystrobin, difenoconazole, fluopyram, ipconazole, mefenoxam (metalaxyl-M), metyltetraprole, silthiofam, dimethomorph, thiophanate-methyl, natamycin, benzovindiflupyr, pydiflumetofen, picarbutrazox, isocycloseram, cyclobutrifluram, broflanilide, thiamethoxam, imidacloprid, clothianidin, cyantraniliprole, chlorantraniliprole, tetraniliprole, and fipronil. The pesticidal combination can preferably comprise an effective amount of active ingredient C. The application rate for the active ingredient C can be as defined in the present invention for the active ingredient A when the active ingredient C is selected from phosphorus pentoxide, dipotassium phosphonate, monopotassium phosphonate, disodium phosphonate, calcium phosphonate, ammonium methyl phosphonate, monoammonium phosphonate, diammonium phosphonate, aluminium tri(ethyl phosphonate), and phosphonic acid; or for the active ingredient B when the active ingredient C is selected from acibenzolar-S-methyl, fludioxonil, fluxapyroxad, inpyrfluxam, mefentrifluconazole, prothioconazole, sedaxane, triticonazole, oxathiapiprolin, fluoxapiprolin, azoxystrobin, difenoconazole, fluopyram, ipconazole, metyltetraprole, silthiofam, dimethomorph, thiophanate-methyl, natamycin, benzovindiflupyr, pydiflumetofen, picarbutrazox, isocycloseram, cyclobutrifluram, broflanilide, thiamethoxam, imidacloprid, clothianidin, cyantraniliprole, chlorantraniliprole, tetraniliprole, and fipronil.

[0031] In the present invention, Oomycetes are phytopathogenic diseases and can be selected from Phytophthora diseases such as those caused by Phytophthora capsici, Phytophthora infestans, Phytophthora sojae, Phytophthora fragariae, Phytophthora nicotianae, Phytophthora cinnamomi, Phytophthora citricola, Phytophthora citrophthora and Phytophthora erythroseptica; Pythium diseases such as those caused by Pythium aphanidermatum, Pythium arrhenomanes, Pythium attrantheridium, Pythium heterothallcium, Pythiumintermedium, Pythium parocecandrum, Pythium spinosum, Pythium sylvaticum, Pythium lutarium, Pythium mamillatum, Pythium graminicola, Pythium irregulars and Pythium ultimum; diseases caused by Peronosporales such as Peronospora destructor, Peronospora parasitica, Plasmopara viticola, Plasmopara halstedii, Peronosclerospora sp. , Pseudoperonospora cubensis, Albugo Candida, Sclerophthora sp., Sclerophthora macrospora, and Premia lactucae; and others such as Aphanomyces cochlioides, Labyrinthula zosterae, Peronosclerospora sorghi and Sclerospora graminicola.

[0032] More preferably, oomycetes can be selected from:

[0033] - Pythium diseases, or in other words Pythium spp., such as those caused by Pythium aphanidermatum, Pythium arrhenomanes, Pythium attrantheridium, Pythium heterothallcium, Pythiumintermedium, Pythium parocecandrum, Pythium spinosum, Pythium sylvaticum, Pythium lutarium, Pythium mamillatum, Pythium graminicola, Pythium irregulars and Pythium ultimum. In a preferred embodiment, the Pythium diseases can be Pythium ultimum, and

[0034] - Peronosporales diseases, such as causedAy Peronospora destructor, Peronospora parasitica, Plasmopara viticola, Plasmopara halstedii, Peronosclerospora sp., Pseudoperonospora cubensis, Albugo Candida, Sclerophthora sp., Sclerospora sp., and Premia lactucae.

[0035] Sunflower downy mildew caused by Plasmopara halstedii occurs in all the major sunflower growing areas worldwide, and is a high resistance risk pathogen. High field infections can lead to yield losses up to 50%. Downy mildew can be seed, soil and air borne. The fungus attacks young tissues and grows systemically within the host plant. It can survive for several years in the soil by oospores. There are very limited options to control this disease which includes tolerant varieties and chemical control, and the present invention propose an effective and consistent control of this disease, especially for managing the resistance development. In a particular embodiment, the following pesticidal combinations comprising the active ingredient A and the active ingredient B can be used against Pythium diseases, and especially against Pythium ultimunr.

[0036] - active ingredient A selecting from phosphorus pentoxide, dipotassium phosphonate, monopotassium phosphonate, disodium phosphonate, calcium phosphonate, ammonium methyl phosphonate, monoammonium phosphonate, diammonium phosphonate, aluminium tri(ethyl phosphonate), and phosphonic acid; and preferably selected from monopotassium phosphonate, dipotassium phosphonate, and diammonium phosphonate; and

[0037] - active ingredient B selected from acibenzolar-S-methyl, fludioxonil, fluxapyroxad, inpyrfluxam, mefentrifluconazole, prothioconazole, sedaxane, triticonazole, oxathiapiprolin, fluoxapiprolin, azoxystrobin, difenoconazole, fluopyram, ipconazole, metyltetraprole, silthiofam, dimethomorph, thiophanate-methyl, natamycin, benzovindiflupyr, pydiflumetofen, picarbutrazox, isocy closeram, cyclobutrifluram broflanilide, thiamethoxam, imidacloprid, clothianidin, cyantraniliprole, chlorantraniliprole, tetraniliprole, and fipronil; and preferably selected from azoxystrobin, benzovindiflupyr, cyclobutrifluram, difenoconazole, dimethomorph, fluoxapiprolin, metyltetraprole, natamycin, oxathiapiprolin, pydiflumetofen, and silthiofam.

[0038] In another particular embodiment, the following pesticidal combinations comprising the active ingredient A and the active ingredient B can be used against Peronosporales diseases, and especially against Plasmopara halstedii'.

[0039] - active ingredient A selecting from phosphorus pentoxide, dipotassium phosphonate, monopotassium phosphonate, disodium phosphonate, calcium phosphonate, ammonium methyl phosphonate, monoammonium phosphonate, diammonium phosphonate, aluminium tri(ethyl phosphonate), and phosphonic acid; and preferably selected from monopotassium phosphonate, dipotassium phosphonate, and diammonium phosphonate; and

[0040] - active ingredient B selected from acibenzolar-S-methyl, fludioxonil, fluxapyroxad, inpyrfluxam, mefentrifluconazole, prothioconazole, sedaxane, triticonazole, oxathiapiprolin, fluoxapiprolin, azoxystrobin, difenoconazole, fluopyram, ipconazole, metyltetraprole, silthiofam, dimethomorph, thiophanate-methyl, natamycin, benzovindiflupyr, pydiflumetofen, picarbutrazox, isocy closeram, cyclobutrifluram broflanilide, thiamethoxam, imidacloprid, clothianidin, cyantraniliprole, chlorantraniliprole, tetraniliprole, and fipronil; and preferably selected from azoxystrobin, benzovindiflupyr, cyclobutrifluram, difenoconazole, dimethomorph, fluoxapiprolin, metyltetraprole, natamycin, oxathiapiprolin, pydiflumetofen, and silthiofam.

[0041] According to the present invention, the active ingredient(s) can be advantageously in the form of a soluble concentrate (SL) or a flowable concentrate for seed treatment (FS) or a suspension concentrate (SC), and can be more preferably a seed treatment slurry to be applied onto seeds. Slurries for seed treatment applications are well-known in the art. For example, a slurry can contain the active ingredient(s), in the form of a commercially available product or not, mixed with water and optionally with at least one polymer as described in the present invention, to optimize adhesion around the plant propagation material.

[0042] In the method of the present invention, the active ingredient(s) can be generally in the form of a composition or formulation containing other customary formulation adjuvants because it allows, for example, less burdensome handling and application.

[0043] Each active ingredient can be applied to the plant propagation material from different compositions respectively, or the active ingredients can be gathered in the same composition (ready-mix composition). The composition may contain from about 0.001% to about 99% by weight of the active ingredient(s) over the total weight of the composition. Suitably, the composition contains from about 0.001% to about 50% by weight active ingredient(s) over the total weight of the composition. More suitably, the composition contains from about 0.001% to about 10% by weight active ingredient(s) over the total weight of the composition. More suitably, the composition contains from about 0.001 % to about 1% by weight active ingredient(s) over the total weight of the composition. If the formulation is in the form of a concentrate, requiring dilution with water before use, it will contain a higher amount of active ingredients than a composition that is ready to use without dilution.

[0044] The active ingredient(s) according to the invention can be used as pesticidal agents in unmodified form, but they are generally formulated into compositions in various ways using formulation adjuvants, such as liquid carriers (or solvents), solid carriers, and surface-active substances. Such formulations can either be used directly or diluted prior to use. The dilutions can be made, for example, with water, liquid fertilizers, micronutrients, biological organisms, oil and / or solvents. The formulations can be prepared e.g. by mixing the active ingredient(s) with the formulation adjuvants in order to obtain compositions in the form of finely divided solids, granules, solutions, dispersions or emulsions. The active ingredients can also be formulated with other adjuvants, such as finely divided solids, mineral oils, oils of vegetable or animal origin, modified oils of vegetable or animal origin, organic solvents, water, surface-active substances, or any mixture thereof.

[0045] The formulation adjuvants that are suitable for the preparation of the compositions according to the invention are known per se.

[0046] As liquid carriers there may be used: 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 acetic acid, diacetone alcohol, 1,2-di chloropropane, diethanolamine, p- diethylbenzene, diethylene glycol, diethylene glycol abietate, diethylene glycol butyl ether, diethylene glycol ethyl ether, diethylene glycol methyl ether, A A -di methyl form am ide, dimethyl sulfoxide, 1,4-di oxane, dipropylene glycol, dipropylene glycol methyl ether, dipropylene glycol dibenzoate, diproxitol, alkylpyrrolidone, ethyl acetate, 2-ethylhexanol, ethylene carbonate, 1,1,1 -tri chloroethane, 2-heptanone, alpha-pinene, d-limonene, ethyl lactate, ethylene glycol, ethylene glycol butyl ether, ethylene glycol methyl ether, gammabutyrolactone, glycerol, glycerol acetate, glycerol diacetate, glycerol triacetate, hexadecane, hexylene glycol, isoamyl acetate, isobornyl acetate, isooctane, isophorone, isopropylbenzene, isopropyl myristate, lactic acid, laurylamine, mesityl oxide, methoxypropanol, methyl isoamyl ketone, methyl isobutyl ketone, methyl laurate, methyl octanoate, methyl oleate, methylene chloride, m-xylene, / / -hexane, / / -octyl amine, octadecanoic acid, octylamine acetate, oleic acid, oleylamine, o-xylene, phenol, polyethylene glycol, propionic acid, propyl lactate, propylene carbonate, propylene glycol, propylene glycol methyl ether, p-xylene, toluene, triethyl phosphate, triethylene glycol, xylenesulfonic acid, paraffin, mineral oil, trichloroethylene, perchloroethylene, ethyl acetate, amyl acetate, butyl acetate, propylene glycol methyl ether, diethylene glycol methyl ether, methanol, ethanol, isopropanol, and alcohols of higher molecular weight, such as amyl alcohol, tetrahydrofurfuryl alcohol, hexanol, octanol, ethylene glycol, propylene glycol, glycerol, A-methyl-2 -pyrrolidone and the like.

[0047] The solid carrier can be a natural or synthetic solid material that is insoluble in water.

[0048] This carrier is generally inert and acceptable in agriculture, especially on the treated seed or other propagation material. It can be chosen, for example, from clay, diatomaceous earth, natural or synthetic silicates, titanium dioxide, magnesium silicate, aluminum silicate, talc, pyrophyllite clay, silica, attapulgite clay, kieselguhr, chalk, limestone, calcium carbonate, calcium montmorillonite, bentonite clay, Fuller's earth, cottonseed husks, wheat flour, soybean flour, pumice, wood flour, ground walnut shells, lignin, and the like.

[0049] A large number of surface-active substances can advantageously be used in both solid and liquid formulations, especially in those formulations which can be diluted with a carrier prior to use. Surface-active substances may be anionic, cationic, non-ionic or polymeric, and they can be used as emulsifiers, wetting agents or suspending agents or for other purposes. Typical surface-active substances include, for example, salts of alkyl sulfates, such as diethanolammonium lauryl sulfate; salts of alkylarylsulfonates, such as calcium dodecylbenzenesulfonate; alkylphenol / alkylene oxide addition products, such as nonylphenol ethoxylate; alcohol / alkylene oxide addition products, such as tridecylalcohol ethoxylate; soaps, such as sodium stearate; salts of alkylnaphthalenesulfonates, such as sodium dibutylnaphthalenesulfonate; dialkyl esters of sulfosuccinate salts, such as sodium di(2- ethylhexyl)sulfosuccinate; sorbitol esters, such as sorbitol oleate; quaternary amines, such as lauryltrimethylammonium chloride, polyethylene glycol esters of fatty acids, such as polyethylene glycol stearate; block copolymers of ethylene oxide and propylene oxide; and salts of mono- and di-alkylphosphate esters; and also further substances described e.g. in McCutcheon's Detergents and Emulsifiers Annual, MC Publishing Corp., Ridgewood New Jersey (1981).

[0050] Further adjuvants that can be used in pesticidal formulations include crystallisation inhibitors, viscosity modifiers, suspending agents, dyes, anti-oxidants, foaming agents, light absorbers, mixing auxiliaries, antifoams, complexing agents, neutralising or pH-modifying substances and buffers, corrosion inhibitors, fragrances, wetting agents, take-up enhancers, micronutrients, plasticisers, glidants, lubricants, dispersants, thickeners, antifreezes, microbicides, and liquid and solid fertilisers.

[0051] The composition according to the present invention generally comprises from 1 to 99.9 % by weight of a formulation adjuvant over the total weight of the composition, which preferably includes from 0 to 25 % by weight of a surface-active substance over the total weight of the composition. Whereas commercial products may preferably be formulated as concentrates, the end user will normally employ dilute formulations. The composition of the present invention may further comprise an additional agrochemical. The additional agrochemical can be an insecticide, a fungicide, an herbicide, a synergist, a plant growth regulator, a nematicide, a plant nutrient, a plant fertilizer, and a mixture thereof.

[0052] Even distribution of the composition of the invention and adherence thereof to the propagation material is desired during the treatment process, this is particularly preferable when the propagation material is a seed. The treatment could vary from a thin film of the formulation containing the composition of the invention on a plant propagation material, such as a seed, where the original size and / or shape are recognizable to a thick film (such as a coating or pelleting with many layers of different materials (such as carriers, for example, clays; different formulations, such as of active ingredients; polymers; and colourants)) where the original shape and / or size of the seed is no longer recognisable.

[0053] More particularly, said thin film can be a film-forming polymer well-known in the art. The composition can include at least one polymer selected from water-soluble and water- dispersible film-forming polymers. Suitable polymers have an average molecular weight of at least about 1,000 up to about 100,000; more specifically at least about 5,000, up to about 100,000. The aqueous compositions generally contain from about 0.5% to about 10% by weight of the composition of polymer (b). In a specific embodiment, the compositions contain from about 1.0% up to about 5% by weight of a film-forming polymer. Suitable polymers are selected from alkyleneoxide random and block copolymers such as ethylene oxi de-propylene oxide block copolymers (EO / PO block copolymers) including both EO-PO-EO and PO-EO- PO block copolymers; ethylene oxi de-butylene oxide random and block copolymers; C2-6 alkyl adducts of ethylene oxi de-propylene oxide random and block copolymers; C2-6 alkyl adducts of ethylene oxi de-butylene oxide random and block copolymers; polyoxyethylenepolyoxypropylene monoalkylethers such as methyl ether, ethyl ether, propyl ether, butyl ether or mixture thereof; vinylacetate / vinylpyrrolidone copolymers; alkylated vinylpyrrolidone copolymers; polyvinylpyrrolidone; polyalkyleneglycol including the polypropylene glycols and polyethylene glycols; and any mixture thereof. Specific examples of suitable polymers include Pluronic P103 (BASF) (EO-PO-EO block copolymer), Pluronic P65 (BASF) (EO-PO- EO block copolymer), Pluronic Pl 08 (BASF) (EO-PO-EO block copolymer), Vinamul 18160 (National Starch) (polyvinylacetate), Agrimer 30 (ISP) (polyvinylpyrrolidone), Agrimer VA7w (ISP) (vinyl acetate / vinylpyrrolidone copolymer), Agrimer AL 10 (ISP) (alkylated vinylpyrrolidone copolymer), PEG 400 (Uniqema) (polyethylene glycol), Pluronic R 25R2 (BASF) (PO-EO-PO block copolymer), Pluronic R 31R1 (BASF) (PO-EO-PO block copolymer) and Witconol NS 500LQ (Witco) (butanol PO-EO copolymer).

[0054] Accordingly, the active ingredient(s) of the invention, and more preferably the composition(s) comprising the active ingredient(s), can preferably adhere to the propagation material, such as a seed.

[0055] Although it is believed that the present method can be applied to a seed in any physiological state, it is preferred that the seed be in a sufficiently durable state that it incurs no damage during the treatment process. Typically, the seed would be a seed that had been harvested from the field; removed from the plant; and separated from any cob, stalk, outer husk, and surrounding pulp or other non-seed plant material. The seed would preferably also be biologically stable to the extent that the treatment would cause no biological damage to the seed. It is believed that the treatment can be applied to the seed at any time between harvest of the seed and sowing of the seed or during the sowing process (seed directed applications).

[0056] The composition according to the present invention can be applied to seeds using conventional treating techniques and machines, such as fluidized bed techniques, the roller mill method, rotostatic seed treaters, and drum coaters. Other methods, such as spouted beds may also be useful. The seeds may be pre-sized before coating. After coating, the seeds are typically dried and then transferred to a sizing machine for sizing. Such procedures are known in the art and are set out in more detail below.

[0057] The composition used in the method according to the present invention can be called a dressing composition, which relates to a liquid composition useful for covering and / or wetting a plant propagation material, and more preferably a seed, at least in part or in totality.

[0058] The composition according to the present invention is particularly suited for dressing applications on plant propagation material, especially on seeds. The techniques of seed treatment application are well known to those skilled in the art, and they may be used readily in the context of the present invention. The compositions of the invention is applied to the seed as slurry or a soak. There also may be mentioned, e.g., film coating or encapsulation. The coating processes are well known in the art, and employ, for seeds, the techniques of film coating or encapsulation, or for the other multiplication products, the techniques of immersion. One method of applying the composition according to the invention consists in spraying or wetting the plant propagation material with the aqueous liquid preparation, or mixing the plant material with such liquid preparation. Also, before the application, the composition of the invention may be diluted with water by simple mixing at ambient temperature in order to prepare an on-farm seed treatment formulation.

[0059] Typically, a tank-mix formulation for seed treatment application comprises 0.25 % to 80 % by weight, especially 1 to 75 % by weight, of active ingredient(s), and 99.75 % to 20 % by weight, especially 99 % to 25 % by weight, of a solid or liquid auxiliary (including, for example, a solvent such as water), where the auxiliaries can be a surfactant in an amount of 0 to 40 % by weight, especially 0.5 to 30 % by weight, based on the total weight of the tank-mix formulation.

[0060] Typically, a pre-mix formulation for seed treatment application comprises 0.5 to 99.9 % by weight, especially 1 to 95 % by weight, of acti ve ingredient(s), and 99.5 to 0.1 % by weight, especially 99 to 5 % by weight, of a solid or liquid adjuvant (including, for example, a solvent such as water), where the auxiliaries can be a surfactant in an amount of 0 to 50 % by weight, especially 0.5 to 40 % by weight, based on the total weight of the pre-mix formulation.

[0061] Whereas commercial products will preferably be formulated as concentrates (e.g., premix composition (formulation)), the end user will normally employ dilute formulations (e.g., tank mix composition).

[0062] Preferred formulations can have the following compositions (weight %):

[0063] Emulsifiable concentrates: active ingredient: 1 to 95 %, preferably 60 to 90 % surface-active agent: 1 to 30 %, preferably 5 to 20 % liquid carrier: 1 to 80 %, preferably 1 to 35 %

[0064] Dusts: active ingredient: 0.1 to 10 %, preferably 0.1 to 5 % solid carrier: 99.9 to 90 %, preferably 99.9 to 99 % Suspension concentrates: active ingredient: 5 to 75 %, preferably 10 to 50 % water: 94 to 24 %, preferably 88 to 30 % surface-active agent: 1 to 40 %, preferably 2 to 30 %

[0065] Wettable powders: active ingredient: 0.5 to 90 %, preferably 1 to 80 % surface-active agent: 0.5 to 20 %, preferably 1 to 15 % solid carrier: 5 to 95 %, preferably 15 to 90 %

[0066] Granules: active ingredient: 0.1 to 30 %, preferably 0.1 to 15 % solid carrier: 99.5 to 70 %, preferably 97 to 85 %

[0067] Flowable concentrates for seed treatment: active ingredient: 1 to 75 %, preferably 10 to 50 % water: 98 to 24 %, preferably 88 to 30 % surface-active agent: 1 to 30 %, preferably 2 to 20 %

[0068] Soluble concentrate: active ingredient: 1 to 95 %, preferably 10 to 80 % liquid carrier: 5 to 99 %, preferably 20 to 90 %

[0069] The following Examples further illustrate, but do not limit, the invention.

[0070] The combination is thoroughly mixed with the adjuvants and the mixture is thoroughly ground in a suitable mill, affording wettable powders that can be diluted with water to give suspensions of the desired concentration.

[0071] The combination is thoroughly mixed with the adjuvants and the mixture is thoroughly ground in a suitable mill, affording powders that can be used directly for seed treatment.

[0072]

[0073] Emulsions of any required dilution, which can be used in plant protection, can be obtained from this concentrate by dilution with water.

[0074] Ready-for-use dusts are obtained by mixing the combination with the carrier and grinding the mixture in a suitable mill. Such powders can also be used for dry dressings for seed.

[0075] The combination is mixed and ground with the adjuvants, and the mixture is moistened with water. The mixture is extruded and then dried in a stream of air.

[0076] The finely ground combination is uniformly applied, in a mixer, to the kaolin moistened with polyethylene glycol. Non-dusty coated granules are obtained in this manner.

[0077] Suspension concentrate The finely ground combination is intimately mixed with the adjuvants, giving a suspension concentrate from which suspensions of any desired dilution can be obtained by dilution with water. Using such dilutions, living plants as well as plant propagation material can be treated and protected against infestation by microorganisms, by spraying, pouring or immersion.

[0078] Flowable concentrate for seed treatment

[0079] The finely ground combination is intimately mixed with the adjuvants, giving a suspension concentrate from which suspensions of any desired dilution can be obtained by dilution with water. Using such dilutions, living plants as well as plant propagation material can be treated and protected against infestation by microorganisms, by spraying, pouring or immersion.

[0080] Soluble concentrate

[0081] Solution of any required dilution, which can be used in plant protection, can be obtained from this concentrate by dilution with water.

[0082] Slow Release Capsule Suspension

[0083] 28 parts of the combination are mixed with 2 parts of an aromatic solvent and 7 parts of toluene diisocyanate / polymethylene-polyphenylisocyanate-mixture (8: 1). This mixture is emulsified in a mixture of 1.2 parts of polyvinylalcohol, 0.05 parts of a defoamer and 51.6 parts of water until the desired particle size is achieved. To this emulsion a mixture of 2.8 parts 1,6-diaminohexane in 5.3 parts of water is added. The mixture is agitated until the polymerization reaction is completed. The obtained capsule suspension is stabilized by adding 0.25 parts of a thickener and 3 parts of a dispersing agent. The capsule suspension formulation contains 28% of the active ingredients. The medium capsule diameter is 8-15 microns. The resulting formulation is applied to seeds as an aqueous suspension in an apparatus suitable for that purpose.

[0084] Another object of the present invention is a plant propagation material, such as for example a seed, treated with the pesticidal combination as defined in the present invention.

[0085] In the present invention, each active ingredient can be applied to the plant propagation material from different compositions respectively, or the active ingredients can be gathered in the same composition, such as for example a ready-mix composition or a tank-mix composition.

[0086] The pesticidal combination can be applied in a weight ratio of the active ingredient A to the active ingredient B as described in the present invention. Another object of the present invention is a use of said pesticidal combination, against Oomycetes (Oomycota phytopathogens), and more preferably against Pythium diseases and / or Peronosporales diseases.

[0087] Another object of the present invention is a method of controlling, limiting or preventing an infestation of a plant, which comprises applying to a growing locus of said plant, said pesticidal combination, preferably against Oomycetes (Oomycota phytopathogens), and more preferably against Pythium diseases and / or Peronosporales diseases.

[0088] In the present invention, the term “locus” as used herein means fields in or on which plants are growing, or where seeds of cultivated plants are sown, or where seed will be placed into the soil. It includes soil, seeds, and seedlings, as well as established vegetation.

[0089] In the present invention, the above uses and methods can exclude treatment of the human or animal body by surgery or therapy and diagnostic methods practised on the human or animal body.

[0090] Examples

[0091] The following non-limiting examples demonstrate the improved behaviour associated with a method according to the present invention.

[0092] A synergistic effect exists whenever the action of an active ingredient combination is greater than the sum of the actions of the individual components. The action to be expected E for a given active ingredient combination obeys the so-called COLBY formula and can be calculated as follows (COLBY, S.R. "Calculating synergistic and antagonistic responses of herbicide combination", Weeds, Vol. 15, pages 20-22; 1967): ppm = milligrams of active ingredient (= a.i.) per liter of spray mixture

[0093] X = % action by active ingredient A using p ppm of active ingredient

[0094] Y = % action by active ingredient B using q ppm of active ingredient.

[0095] According to COLBY, the expected (additive) action of active ingredients A+B using p+q ppm of active ingredient is

[0096] 100 If the action actually observed (O) is greater than the expected action (E), then the action of the combination is super-additive, i.e. there is a synergistic effect. In mathematical terms, synergism corresponds to a positive value for the difference of (O-E). In the case of purely complementary addition of activities (expected activity), said difference (O-E) is zero. A negative value of said difference (O-E) signals a loss of activity compared to the expected activity.

[0097] Activity against Pythium spp. (damping off)

[0098] The objective of this study was to evaluate the activity of the combination comprising a phosphorus-based compound and active ingredient B, against Pythium spp. especially Pythium ultimum.

[0099] The following products were tested in laboratory experiments and are gathered in the below Table 1 :

[0100] - MONOPOTASSIUM PHOSPHITE, formula: H2O3PK, CAS-No: 13977-65-6;

[0101] - DIPOTASSIUM PHOSPHITE, formula: HO3P2K, CAS-No: 13492-26-7;

[0102] - DIAMMONIUM PHOSPHONATE, formula: H9N2O3P, CAS-No: 22132-71 -4;

[0103] - OXATHIAPIPROLIN, CAS-No: 1003318-67-9;

[0104] - FLUOX APIPROLIN, CAS-No: 1360819-11-9;

[0105] - AZOXYSTROBIN, CAS-No: 131860-33-8;

[0106] - DIFENOCONAZOLE, CAS-No: 119446-68-3;

[0107] - METYLTETRAPROLE, CAS-No: 1472649-01-6;

[0108] - SILTHIOFAM, CAS-No: 175217-20-6;

[0109] - DIMETHOMORPH, CAS-No: 110488-70-5;

[0110] - NATAMYCIN, CAS-No: 7681-93-8;

[0111] - BENZOVINDIFLUPYR, CAS-No: 1072957-71-1;

[0112] - PYDIFLUMETOFEN, CAS-No: 1228284-64-7; and

[0113] - CYCLOBUTRIFLURAM, CAS-No: 1644251-74-0.

[0114] Mycelial fragments of the pathogen, prepared from a fresh liquid culture, were directly mixed into nutrient broth (potato dextrose broth). A DMSO solution of the test compounds was placed into a microtiter plate (96-well format) and the nutrient broth containing the mycelial fragments was added to it. The test plates were incubated at 24°C and the growth inhibition of the pathogen was determined after 48 hours.

[0115] Table 1 shows the in vitro efficacy (%) of the active ingredients under controlled conditions, against Pythium ultimum.

[0116] Table 1

[0117] The tested active ingredients according to the invention, which are based on a phosphorus-based compound (active ingredient A) mixed with the active ingredient B, guarantee a good efficacy against Pythium spp., especially Pythium ultimum.

Claims

CLAIMS1. A method of controlling, limiting or preventing an infestation of a plant by Oomycetes, which comprises applying to propagation material of said plant, a pesticidal combination comprising a phosphorus-based compound as active ingredient A, and an active ingredient B selected from acibenzolar-S-methyl, fludioxonil, fluxapyroxad, inpyrfluxam, mefentrifluconazole, prothioconazole, sedaxane, tri ti conazole, oxathiapiprolin, fluoxapiprolin, azoxystrobin, difenoconazole, fluopyram, ipconazole, metyltetraprole, silthiofam, dimethomorph, thiophanate-methyl, natamycin, benzovindiflupyr, pydiflumetofen, picarbutrazox, isocycloseram, cyclobutrifluram, broflanilide, thiamethoxam, imidacloprid, clothianidin, cyantraniliprole, chlorantraniliprole, tetraniliprole, fipronil, any mixture thereof.

2. The method according to claim 1, characterized in that the active ingredient B is selected from azoxystrobin, benzovindiflupyr, cyclobutrifluram, difenoconazole, dimethomorph, fluoxapiprolin, metyltetraprole, natamycin, oxathiapiprolin, pydiflumetofen, silthiofam, and any mixture thereof.

3. The method according to claim 1 or 2, characterized in that the phosphorus-based compound is selected from phosphonic acid, one or several phosphonate salts, and any mixture thereof.

4. The method according to any one of the preceding claims, characterized in that the Oomycetes are selected from Pythium diseases and from Peronosporales diseases.

5. The method according to any one of the preceding claims, characterized in that the Oomycetes are Pythium ultimum and / or Plasmopara halstedii.

6. The method according to any one of the preceding claims, characterized in that the weight ratio of the active ingredient A to the active ingredient B is from 1 : 100 to 1000: 1, preferably from 1 : 100 to 400: 1, preferably from 1 : 100 to 100: 1, and more preferably from 1 : 10 to 10: 1.

7. The method according to any one of the preceding claims, characterized in that the plant is selected from vegetables, legume crops, oil crops, beets, fibre plants, and cereals.

8. The method according to any one of the preceding claims, characterized in that the application rate can be from 1 gram to 500 grams of the active ingredient A, preferably from 10 grams to 400 grams of the active ingredient A, preferably from 20 grams to 300 grams of the active ingredient A, preferably from 30 grams to 300 grams of the active ingredient A, and more preferably from 30 grams to 200 grams of the active ingredient A, over 100 kg of plant propagation material.

9. The method according to any one of the preceding claims, characterized in that the application rate is from 0.5 gram to 250 grams of the active ingredient B, preferably from 1 gram to 200 grams of the active ingredient B, preferably from 1 gram to 100 grams of the active ingredient B, preferably from 1 gram to 50 grams of the active ingredient B, and more preferably from 1 gram to 30 grams of the active ingredient B, over 100 kg of plant propagation material.

10. The method according to any one of the preceding claims, characterized in that the plant propagation material is plant seeds.

11. A plant propagation material treated with a pesticidal combination as defined in any one of the preceding claims.

12. Use of a pesticidal combination as defined in any one of claims 1 to 10, against Oomycetes.

13. Use according to claim 12, characterized in that the pesticidal combination is applied to a plant propagation material, and preferably to a seed.

14. Use according to claim 12 or 13, characterized in that the Oomycetes are selected from Pythium diseases and Peronosporales diseases.