GB2612369A

GB2612369A - Aqueous suspension antimicrobial composition

Info

Publication number: GB2612369A
Application number: GB2115705.2A
Authority: GB
Inventors: Timothy Bristow James
Original assignee: Rotam Agrochem International Co Ltd
Current assignee: Rotam Agrochem International Co Ltd
Priority date: 2021-11-02
Filing date: 2021-11-02
Publication date: 2023-05-03
Also published as: GB202115705D0

Abstract

An antimicrobial composition comprising a strobilurin fungicide and at least one fatty alcohol polyoxyethylene ether (APEO). Also discloses: an aqueous suspension comprising a strobilurin, at least one C2 -C25 APEO having an ethylene oxide (EO) number of 5-50, and optionally other surfactants; an aqueous suspension comprising 50-300 g/L of strobilurins, 25-250 g/L of C2-C25 APEO, 0-200 g/L of other surfactants, and water up to 1 L; and an aqueous suspension comprising 50-300 g/L of strobilurins, 25-250 g/L of C10-C20 APEO, 0-200 g/L of other surfactants, and water up to 1 L. Further defines a method for controlling microbial infestations comprising applying at least one strobilurin and APEO to plants, use of at least one strobilurin and APEO to control microbial infestations and to increase crop yields, and use of an APEO to increase the antimicrobial activity of strobilurins. The strobilurin is preferably azoxystrobin, picoxystrobin, or pyroclostrobin and the APEO may have the formula R-O-(CH2-CH2-O)n-H, where R may be a C4-C20 alkyl group and n is 4-40. The strobilurin and APEO may be in between a 10:1 and 1:10 ratio and may be applied separately or together, and the strobilurin particles may be below 5 µm in an aqueous suspension.

Description

AQUEOUS SUSPENSION ANTIMICROBIAL COMPOSITION

The present invention relates to an aqueous suspension antimicrobial composition, more particularly to an azoxystrobin aqueous suspension antimicrobial composition. The present invention further relates to the use of the composition in the control of microbial infestations.

The strobilurin fungicides are a class of compounds exhibiting antimicrobial activity and are used extensively in the control of fungal infestations in plants, in particular valuable crop plants. The class includes the strobilurin fungicides, the methoxyacrylate strobilurin fungicides, the methoxycarbanilate strobilurin fungicides, the methoxyiminoacetamide strobilurin fungicides, and the methoxyiminoacetate strobilurin fungicides. Strobilurin fungicides are active as quinone outside (Qo) inhibitors and interrupt the respiratory chain within the target pathogen.

Azoxystrobin belongs to the class of methoxyacrylate strobilurin antimicrobial agents and has a molecular formula of C22H17N305. The molecule can be represented as follows: H3C Azoxystrobin has a wide antimicrobial activity and exhibits a high level of fungicidal activity, in particular against almost all infestations of Eumycetes (Ascomycetes, Basidiomycetes, Oomycetes and Deuteromycetes), such as powdery mildew, rust, glume blight, scab, downy mildew, and rice blast. Azoxystrobin acts to inhibit mitochondrial respiration by blocking electron transport. In particular, it binds to the quinol outer binding site of the cytochrome b-c1 complex, where ubiquinone (coenzyme Q10) would normally bind when carrying electrons to the protein. As a result the production of ATP within the organism is prevented. However, due to the single action site of azoxystrobin, heavy and repeated use results in the target pathogens developing resistance to treatment. In order to gain improved control, it is known for end users to increase the dosage of azoxystrobin being applied, in turn increasing the level of resistance developed by the target pests. The large amounts of azoxystrobin required for effective treatment can cause pollution to food and the environment.

Azoxystrobin is produced on a commercial scale and is available commercially in a range of formulations. Currently, there are a number of commercial, single-agent formulations of azoxystrobin. One formulation comprises an aqueous suspension concentrate of azoxystrobin in an amount of 250 g/L. An alternative formulation commercially available provides aqueous dispersible granules of azoxystrobin in an amount of 50% by weight. The use of these formulations in the manner described above readily leads to pathogenic bacteria developing pesticide resistance to the long-term use of azoxystrobin.

Antimicrobial agents, such as azoxystrobin, are known to be combined with a range of different auxiliaries, depending upon the needs of the different types of formulation. In a number of formulations, it is known to combine the active compounds with one or more surfactants, in particular when the active ingredient is to be used in a liquid-based formulation. One such type of formulation is an aqueous suspension concentrate (SC). Suspension concentrate formulations have a number of advantages over alternative liquid formulations that employ organic solvents. Since water is the dispersion medium of an aqueous suspension preparation, the formulation has a reduced toxicity, causes less irritation to users, has reduced odor, and gives rise to fewer environmental pollution problems, compared with formulations relying on organic solvents.

There is a need for an improved formulation for the strobilurin fungicides. In particular, it would be advantageous if the effectiveness of strobilurin fungicides could be increased, in particular in the control of phytopathogenic fungi. It would be advantageous if the life cycle of the strobilurin compounds could also be extended.

It has now been found that a combination of one or more strobilurin fungicides and a fatty alcohol polyoxyethylene ether exhibits a synergistic effect, resulting in a significantly increased biological activity of the strobilurin compounds against phytopathogenic fungi. The combination of strobilurin fungicides and the fatty alcohol polyoxyethylene ether can be employed in a number of different formulations. It has been found that the combination is particularly advantageous when formulated as an aqueous suspension antimicrobial composition. In addition, it has been found that the combination of strobilurin fungicides and a fatty alcohol polyoxyethylene ether can increase the yield of crop plants.

In a first aspect, the present invention provides an antimicrobial composition comprising: a) a strobilurin fungicide; and b) at least one fatty alcohol polyoxyethylene ether.

In one embodiment, the present invention provides an aqueous suspension antimicrobial composition comprising: a) a strobilurin fungicide; b) at least one fatty alcohol polyoxyethylene ether; c) optionally one or more other agrochemically acceptable surfactants; and d) water.

The compositions of the present invention, especially the aqueous suspension antimicrobial composition of the present invention, exhibits a significantly improved biological activity. In particular, a combination of one or more strobilurin fungicides and a fatty alcohol polyoxyethylene ether exhibits a synergistic effect giving an improved biological activity in the control of a range of antimicrobial infestations.

This synergistic effect is unforeseen.

In a preferred embodiment, the present invention provides an aqueous suspension antimicrobial composition, comprising: a) a strobilurin fungicide; b) at least one C2-C25 fatty alcohol polyoxyethylene ether having an average EO number of 5-50; c) optionally one or more other agrochemically acceptable surfactants; and d) water.

In a preferred embodiment, the aqueous suspension antimicrobial composition comprises: a) 50 g/L to 300 g/L of one or more strobilurin fungicides; b) 25 g/L to 250 g/L of at least one fatty alcohol polyoxyethylene ether; c) 0 g/L to 200 g/L of one or more other agrochemically acceptable surfactants; and d) water making up to 1 L. In a particularly preferred embodiment, the aqueous suspension antimicrobial composition comprises: a) 50 g/L to 300 g/L ofone or more strobilurin fungicides; b) 25 g/L to 250 g/L of at least one C2-025 fatty alcohol polyoxyethylene ether having an average E0 number of from 5 to 50; c) 0 g/L to 200 g/L of one or more other agrochemically acceptable surfactants; and d) water making up to 1 L. In a more particularly preferred embodiment, the aqueous suspension antimicrobial composition comprises: a) 50 g/L to 300 g/L ofone or more strobilurin fungicides; b) 25 g/L to 250 g/L of at least one Cio-C20 fatty alcohol polyoxyethylene ether io having an average E0 number of from 5 to 50; c) 0 g/L to 200 g/L of one or more other agrochemically acceptable surfactants; and d) water making up to 1 L. The present invention employs one or more strobilurin fungicides. The strobilurin fungicide may be a naturally occurring strobilurin or a synthetic strobilurin. The strobilurin fungicide may be selected from the methoxyacrylate strobilurin fungicides, the methoxycarbanilate strobilurin fungicides, the methoxyiminoacetamide strobilurin fungicides, and the methoxyiminoacetate strobilurin fungicides. Suitable strobilurin fungicides for use in the present invention include fluoxastrobin, mandestrobin, or pyribencarb. Suitable methoxyacrylate strobilurin fungicides include azoxystrobin, bifujunzhi, coumoxystrobin, enoxastrobin, flufenoxystrobin, jiaxiangjunzhi, picoxystrobin, and pyraoxystrobin. Suitable methoxycarbanilate strobilurin fungicides include pyraclostrobin, pyrametostrobin, and triclopyricarb. Suitable methoxyim inoacetam ide strobilurin fungicides include dim oxystrobin, fenaminstrobin, metom inostrobin, and orysastrobin. Suitable methoxyiminoacetate strobilurin fungicides include kresoxim-methyl and trifloxystrobin.ln a preferred embodiment, the one or more strobilurin fungicides are selected from the methoxyacrylate strobilurin fungicides, in particular azoxystrobin, bifujunzhi, coumoxystrobin, enoxastrobin, flufenoxystrobin, jiaxiangjunzhi, picoxystrobin, and pyraoxystrobin. Azoxystrobin and picoxystrobin are two preferred methoxyacrylate strobilurin fungicides. Azoxystrobin is a particularly preferred strobilurin fungicide for use in the present invention.

In one preferred embodiment, the one or more strobilurin fungicides are to selected from the methoxycarbanilate strobilurin fungicides, especially pyraclostrobin.

In the composition of the present invention, the content of the strobilurin fungicide may be any amount to achieve the required antimicrobial activity. Preferably, the strobilurin fungicide is present in an amount of at least 20 g/L, more preferably from 50 g/L, still more preferably from 100 g/L, more preferably still from g/L, especially from 200 g/L. Preferably, the strobilurin fungicide is present in an amount of up to 450 g/L, more preferably up to 400 g/L, still more preferably up to 350 g/L, more preferably still up to 300 g/L, especially up to 280 g/L, more especially up to 280 g/L. In preferred embodiments, strobilurin fungicide is present in an amount of from 50 g/L to 300 g/L, preferably from 100 g/L to 300 g/L, more preferably from 150 /L to 280 g/L, still more preferably from 200 g/L to 250 g/L.

The compositions of the present invention further comprise a fatty alcohol polyoxyethylene ether. The fatty alcohol polyoxyethylene ether is active as a surfactant The fatty alcohol polyoxyethylene ether can be represented by the following general formula: R-0-(CH2-CH2-0)n-H (I) in which R represents an alkyl group and n is the ethylene oxide (EO) number.

The fatty alcohol polyoxyethylene ethers of general formula (I) may be considered to be formed from an alcohol having the formula R-OH and ethylene oxide (E0) having a certain E0 number.

The fatty alcohol polyoxyethylene ether may be a straight chain or branched chain fatty alcohol polyoxyethylene ether, that is the alkyl group represented by R may be straight chain or branched chain.

The alkyl group represented by R may have at least 2 carbon atoms, preferably at least 4 carbon atoms, more preferably at least 6 carbon atoms, still more preferably at least 8 carbon atoms, more preferably still at least 10 carbon atoms. The alkyl group represented by R may have up to 30 carbon atoms, preferably up to 28 carbon atoms, more preferably up to 26 carbon atoms, still more preferably up to 25 carbon atoms, more preferably still up to 24 carbon atoms, especially up to 22 carbon atoms, more especially up to 20 carbon atoms. In one preferred embodiment, R is an alkyl group having from 2 to 25 carbon atoms, more preferably from 4 to 24 carbon atoms, still more preferably from 6 to 22 carbon atoms, more preferably still from 8 to 20 carbon atoms, especially from 10 to 20 carbon atoms.

Suitable fatty alcohols for forming the fatty alcohol polyoxyethylene ether include ethanol, propanol, butanol, pentanol, hexanol, octanol, decanol, C12 alcohol, C14 alcohol, Cm alcohol, Cm alcohol, C20 alcohol, C22 alcohol, and C25 alcohol. Preferred fatty alcohol polyoxyethylene ethers may be selected from ethanol polyoxyethylene ether, butanol polyoxyethylene ether, pentanol polyoxyethylene ether, hexanol polyoxyethylene ether, octanol polyoxyethylene ether, decanol polyoxyethylene ether, C12 alcohol polyoxyethylene ether, C14 alcohol Polyoxyethylene ether, C16 alcohol polyoxyethylene ether, C18 alcohol polyoxyethylene ether, C20 alcohol polyoxyethylene ether, C22 alcohol polyoxyethylene ether, and C25 alcohol polyoxyethylene ether Preferably, the fatty alcohol polyoxyethylene ether is a C4-C20 alcohol polyoxyethylene ether. More

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preferably, the fatty alcohol polyoxyethylene ether is a C10-C20 alcohol polyoxyethylene ether.

The composition of the present invention may comprise a fatty alcohol polyoxyethylene ether having any suitable ethylene oxide (EO) number Preferably, the fatty alcohol polyoxyethylene ether has an EO number, that is a value of n in the general formula (I), of at least 2, more preferably at least 4, still more preferably at least 6, more preferably still at least 8. The fatty alcohol polyoxyethylene ether may have an EO number, that is the value of n in the general formula (I), of up to 50, preferably up to 48, more preferably up to 45, still more preferably up to 42, more preferably still up to 40. Suitable EO numbers are from 2 to 50, preferably from 4 to 48, more preferably from 6 to 45, still more preferably from 8 to 40. Suitable EO numbers, that is the value of n in the general formula (I), can be 2, 4, 8, 10, 12, 15, 18, 20, 22, 24, 25, 28, 30, 33, 36, 40, 42, 44, 45, 46, 48 or 50.

In one embodiment, the fatty alcohol polyoxyethylene ether is selected from a fatty alcohol ether having a value of n of from 2 to 8. In an alternative embodiment, the fatty alcohol polyoxyethylene ether is selected from a fatty alcohol ether having a value of n of from 8 to 18. In an alternative embodiment, the fatty alcohol polyoxyethylene ether is selected from a fatty alcohol ether having a value of n of from 18 to 24. In an alternative embodiment, the fatty alcohol polyoxyethylene ether is selected from a fatty alcohol ether having a value of n of from 24 to 30. In an alternative embodiment, the fatty alcohol polyoxyethylene ether is selected from a fatty alcohol ether having a value of n of from 30 to 40. In an alternative embodiment, the fatty alcohol polyoxyethylene ether is selected from a fatty alcohol ether having a value of n of from 40 to 50.

Preferably, the fatty alcohol polyoxyethylene ether is a fatty alcohol ether having from 4 to 40 E0 groups. More preferably, the fatty alcohol polyoxyethylene ether is a fatty alcohol ether having from 8 to 30 EO groups.

In one particular embodiment, the fatty alcohol polyoxyethylene ether is selected from fatty alcohol ether polyoxyethylene ether in which R is a C4 to C20 alkyl group and n is from 4 to 40, more preferably a fatty alcohol polyoxyethylene ether in which R is a Cio to C20 alkyl group and n is from 8 to 30.

The composition may comprise a single fatty alcohol polyoxyethylene ether Alternatively, the composition may comprise two or more different fatty alcohol polyoxyethylene ethers.

The fatty alcohol polyoxyethylene ether may be present in the composition in any suitable amount to provide the synergistic effect described hereinbefore. Preferably, the fatty alcohol polyoxyethylene ether is present in an amount of at least 25 g/L, more preferably from 50 g/L, still more preferably from 80 g/L, more io preferably still from 100 g/L, especially from 120 g/L. Preferably, the fatty alcohol polyoxyethylene ether is present in an amount of up to 250 g/L, more preferably up to 240 g/L, still more preferably up to 220 g/L, more preferably still up to 200 g/L, especially up to 180 g/L. In preferred embodiments, the fatty alcohol polyoxyethylene ether is present in an amount of from 25 g/L to 250 g/L, preferably from 50 g/L to 240 g/L, more preferably from 80 /L to 220 g/L, still more preferably from 100 g/L to 200 g/L, especially from 120 g/L to 180 g/L.

In the present invention, the strobilurin fungicide and the fatty alcohol polyoxyethylene ether may be employed in a weight ratio of from 10:1 to 1:10, preferably from 5:1 to 1:5, more preferably from 4:1 to 1:4, still more preferably from 3:1 to 1:3. It is preferred that the strobilurin fungicide is employed in a weight excess to the fatty alcohol polyoxyethylene ether, preferably at a weight ratio of from 1.01:1 to 5:1, more preferably from 1.1:1 to 4:1, still more preferably from 1.2:1 to 3:1, more preferably still from 1.5:1 to 2.8:1, especially from 1.6:1 to 2.6:1.

The composition of the present invention optionally comprises one or more auxiliaries, such as one or more other agrochemically acceptable surfactants, for example, a dispersing agent or a wetting agent; a thickening agent; an antifreezing agent; an antifoaming agent; a preservative; and a coloring agent.

Suitable dispersing agents are any substance that can be used in agrochemical preparations for this purpose, for example, nonionic, amphoteric, cationic and anionic (polymer) surfactants. Preferred dispersing agents are EO/PO block copolymers, sulfonic acid of ethoxylated alcohol, sulfosuccinate, fatty acid methyl taurate, tristyryl phenol ethoxylate and alkoxylate, tri-sec-butyl phenol ethoxylate, sulfated cresol-formaldehyde condensate, sulfated condensate of naphthalene and alkyl naphthalene, lignosulfonate, phosphate of ethoxylated fatty alcohol, tristyrylphenol and tri-sec-butylphenol, copolymers of ethoxylated aryl fatty alcohol, polyacrylate, polymethacrylic acid and acrylate, ether sulfate of tristyrylphenol and tri-sec-butylphenol.

Suitable wetting agent are any substance that can be used in agrochemical preparations for this purpose, preferably an anionic wetting agent, for example, alkali metal, alkaline earth metal or ammonium salts of the anionic wetting agent. Suitable wetting agents are naphthalene sulfonate (for example, disodium methylene dinaphthalene sulfonate, sodium naphthalene sulfonate-formaldehyde condensate and ammonium naphthalene sulfonate-formaldehyde condensate), alkyl naphthalene sulfonate (for example, sodium alkyl naphthalene sulfonate), benzene sulfonate, alkyl benzene sulfonate (for example, sodium cumene sulfonate, potassium cumene sulfonate, sodium xylene sulfonate and sodium toluene sulfonate), alkane sulfonate (for example, sodium tetradecene sulfonate), a-olefin sulfonate (for example, sodium a-olefin sulfonate), sulfosuccinate (for example, sodium dioctyl sulfosuccinate), alkyl phosphate (for example, lauryl myristyl phosphate) and alkyl sulfate (for example, sodium lauryl sulfate, sodium cetyl stearyl sulfate, sodium cetyl sulfate, sodium myristyl sulfate and sodium cetyl stearyl sulfate).

The thickening agent may be selected from an organic thickening agent and/or an inorganic thickening agent, preferably a combination of an organic thickening agent and an inorganic thickening agent. Suitable organic thickening agents may be selected from xanthan gum, welan gum, kelco-crete, carrageenan, guar gum, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, butyl acetate cellulose, polyvinyl alcohol, polyvinylpyrrolidone, alkali swelling polyacrylic acid, pregelatinized modified starch, carboxypropyl guar gum, polyacrylamide and sodium polyacrylate. The organic thickening agent is preferably xanthan gum.

Suitable inorganic thickening agents may be selected from mineral fine powder, such as magnesium aluminum silicate, montmorillonite, bentonite, hectorite, or fumed silica, or alumina sol. Magnesium aluminum silicate is a preferred inorganic thickening agent, as when added in a small amount the viscosity of the formulation is easy to control.

The composition preferably contains a combination of an organic thickening agent and an inorganic thickening agent. The weight ratio of the organic thickening agent to the inorganic thickening agent may be from 1:1 to 1:20, preferably from 1:2 to 1:18, more preferably from 1:5 to 1:15, still more preferably from 1:8 to 1:12.

The antifreezing agent suitable for use in the present invention may be selected from urea, diols and polyols, for example, ethylene glycol, diethylene glycol, propylene glycol and glycerin, and preferably, propylene glycol and glycerin.

The preservative suitable for use in the present invention is, for example, an isothiazolinone preservative, such as 1,2-benzisothiazolin-3-one, chloromethyl and methylisothiazolinone. Commercially available preservatives include PROXEL 20 GXL (Lonza) and NIPACIDE Cl 15 MV (Clariant) Suitable auxiliaries and their use in preparing the compositions of the present invention are known in the art.

The compositions of the present invention may be prepared using any suitable techniques. Suitable techniques for preparing the compositions, for example the aqueous suspension concentrates of the present invention, are known in the art.

In a further aspect, the present invention provides a method for forming an antimicrobial composition, the method comprising combining the one or more strobilurin fungicides and a fatty alcohol polyoxyethylene ether, optionally with one or more auxiliaries.

In one embodiment, the strobilurin fungicide and the at least one fatty alcohol polyoxyethylene ether, optionally with one or more auxiliaries, may be combined and the resulting mixture milled, for example using wet-milling.

In the case of an aqueous suspension concentrate, the one or more strobilurin fungicides and the at least one fatty alcohol polyoxyethylene ether, optionally with one or more auxiliaries and other additives, if desired, are mixed with water and the resulting mixture subjected to a wet-milling procedure to prepare a dispersed to suspension. Preferably, a thickening agent or/and an aqueous solution of the thickening agent is added to the dispersed suspension and the resulting mixture mixed.

Wet-milling may comprise combining the mixture to be milled with rigid beads, such as zirconium beads, and then subjecting the resulting mixture to wet beads milling. Suitable equipment for conducting the wet-milling is known in the art for commercially available, for example DYNO-MILL O. Alternatively, milling may be effected using a sand mill.

In embodiments in which the composition is an aqueous suspension concentrate of the strobilurin fungicide, the strobilurin fungicide is present in the form of suspended particles. Preferably, the strobilurin fungicide is present in the form of particles having an average particle size below 5 pm, preferably from 0.1 to 3 pm, more preferably from 0.5 to 2.5 pm, still more preferably from 1.0 to 2.0 pm.

As discussed hereinbefore, it has been found that combining one or more strobilurin fungicides with a fatty alcohol polyoxyethylene ether provides a synergistic effect, which increases the activity of the strobilurin fungicide in the control of microbial infestations, in particular fungal infestations, compared with the use of the strobilurin fungicide alone.

In a further aspect, the present invention provides a method for controlling microbial infestations in plants, the method comprising applying to the plants, plant parts, plant propagation materials or their locus one or more strobilurin fungicides and a fatty alcohol polyoxyethylene ether The strobilurin fungicide and the fatty alcohol polyoxyethylene ether may be applied separately, for example by way of separate compositions, or together as a single composition. In one preferred embodiment, a composition as hereinbefore described is employed.

Techniques for applying the strobilurin fungicide and the fatty alcohol polyoxyethylene ether to the plants, plant parts or their locus are known in the art.

In many embodiments, the compositions as hereinbefore described are diluted with a carrier, most preferably water, to the required concentration of active ingredients and the diluted formulation applied to the plants, plant pads or their locus.

The combination of a strobilurin fungicide and a fatty alcohol polyoxyethylene ether of the present invention is effective in the control of a range of microbial infestations, especially in the control of infestations of phytopathogenic fungi in plants, such as Plasmopara viticola on vines, Erysiphales spp., Phytophthora spp. and PseudoperoNospora cubeNsis on vegetables, PeroNospora brassicae on zo cruciferae vegetables, ErysiphegramiNis, SclerotiNia sclerotiorum, PyreNophorateres, VeNturia Nashicola, VeNturia iNaequalis, Colletotrichum lageNarium, AlterNaria mali, AlterNaria solaNi and RhizoctoNia solaNi. The present invention has been found to be particularly effective in the control of infestations of Erysiphales spp. in a range of crop plants, in particular vegetables, especially Cucurbitaceae plants.

The combination of a strobilurin fungicide and a fatty alcohol polyoxyethylene ether can be administered to a plant or a part thereof, particularly, all parts of a plant, such as leaf, stem, branch, root, or the locus of the plants or plant parts, such as the soil in which the plant grows.

The combination of a strobilurin fungicide and a fatty alcohol polyoxyethylene ether exhibits a considerable fungicidal activity and can effectively perform prophylactic, therapeutic and eradicative treatments. The combination of a strobilurin fungicide and a fatty alcohol polyoxyethylene ether exhibits little or no phytotoxicity to the plants or plant parts being treated, especially crop plants.

As discussed above, the effect of combining a strobilurin fungicide with a fatty alcohol polyoxyethylene ether is a synergistic effect, by which the antimicrobial activity of the strobilurin fungicide is significantly increased.

In a further aspect, the present invention provides the use of a fatty alcohol polyoxyethylene ether to increase the antimicrobial activity of a strobilurin fungicide The combination of a strobilurin fungicide and a fatty alcohol polyoxyethylene ether of the present invention is particularly advantageous due to the increased biological activity of the strobilurin fungicide active ingredient. This in turn allows greater control of microbial infestations to be achieved or the amount of the active ingredient be used to be reduced, compared with the existing formulations. The combination of a strobilurin fungicide and a fatty alcohol polyoxyethylene ether may be formulated into a composition, in particular an aqueous suspension concentrate (SC) formulation, having outstanding toxicological and environmental properties.

In addition, as noted hereinbefore, it has been found that the combination of a strobilurin fungicide and a fatty alcohol polyoxyethylene ether of the present invention can increase the yield of crop plants when treated in accordance with the present invention.

Accordingly, in a further aspect, the present invention provides the use of a combination of a strobilurin fungicide and a fatty alcohol polyoxyethylene ether to increase the yield of crop plants.

The increased yield may be achieved in a range of crop plants, especially in vegetables, in particular in Cucurbitaceae plants, such as cucumber plants.

Embodiments of the present invention will now be described, by way of illustration only, in the following working examples.

Percentages are percentage by weight, unless otherwise indicated.

EXAMPLES Example 1

1. Preparation of dispersed mother liquor of azoxvstrobin A fatty alcohol polyoxyethylene ether formed from a C16-Cie alcohol and having an E0 number of 25 (commercial name: GENAPOL T 250 P, ex Clariant) (150 g), naphthalene sulfonate formaldehyde polycondensate (commercial name: MORWET D-425, ex Nouryon) (20g), propylene glycol (60 g) and silicone antifoaming agent (commercial name: SAG 1572, ex Momentive) (5 g) were dispersed in water (370 g). Azoxystrobin (purity 98%) (255 g) was added and the resulting mixture was milled using a sand mill (Dynomill0). The resulting mixture was subjected to a wet-milling procedure using zirconium beads having a diameter of 0.8 to 1.2 mm to obtain 860 g of a dispersed mother liquor containing azoxystrob in.

Thickening medium Xanthan gum (commercial name: AG-RHO POL 23/W, ex Solvay) (2 g), magnesium aluminum silicate (commercial name: VEEGUM R, ex R.T. Vanderbilt) (20 g) and 1,2-benzisothiazolin-3-one (commercial name: PROXEL GXL, ex Lonza) (2 g) were dispersed in water (176 g) to obtain 200 g of a thickening medium.

Formulation of an azoxystrobin aqueous suspension concentrate 860 g of the dispersed mother liquor of azoxystrobin and 200 g of the 5 thickening medium were mixed to obtain 1060 g of an aqueous suspension concentrate composition of azoxystrobin. The average particle size of azoxystrobin was from 1.5 to 1.8 pm.

The components of the suspension concentrate formulation are summarized in Table 1 below.

Table 1

Component Amount Function (9) Azoxystrobin (98 %) 255 Active ingredient Fatty alcohol 150 Surfactant polyoxyethylene ether (R=Cis to Cis; n=25) (GENAPOL T 250 P; ex Clariant) Naphthalene sulfonate formaldehyde polycondensate 20 Surfactant (MORVVET D-425) Propylene glycol 60 Anti-freezing agent Silicone antifoaming agent (SAG 1572) 5 Anti-foaming agent Xanthan gum 2 Thickening agent (AG-RHO POL 23/W) Magnesium aluminum silicate (VEEGUM R) 20 Thickening agent 1,2-benzisothiazolin-3-one (PROXEL GXL) 2 Biocide Water 546 Carrier

Example 2

Using the general procedure described in Example 1 above, an aqueous 5 suspension concentrate formulation was prepared from the components summarized in Table 2 below.

Table 2

Component Amount Function (9) Azoxystrobin (98 %) 255 Active ingredient Fatty alcohol 100 Surfactant polyoxyethylene ether (R=C16 to Cis; n=25) (GENAPOL T 250 P; ex Clariant) Naphthalene sulfonate formaldehyde polycondensate (MORVVET D-425) 20 Surfactant Propylene glycol 60 Anti-freezing agent Silicone antifoaming agent (SAG 1572) 5 Anti-foaming agent Xanthan gum 2 Thickening agent (AG-RHO POL 23/W) Magnesium aluminum silicate (VEEGUM R) 20 Thickening agent 1,2-benzisothiazolin-3-one (PROXEL GXL) 2 Biocide Water 596 Carrier

Example 3

Using the general procedure described in Example 1 above, an aqueous suspension concentrate formulation was prepared from the components summarized in Table 3 below.

Table 3

Component Amount Function (9) Azoxystrobin (98 %) 255 Active ingredient Fatty alcohol 150 Surfactant polyoxyethylene ether (R=C16 to Cia; n=20) (GENAPOL 1200 P; ex Clariant) Naphthalene sulfonate formaldehyde polycondensate 20 Surfactant (MORVVET D-425) Propylene glycol 60 Anti-freezing agent Silicone antifoaming agent 5 Anti-foaming agent (SAG 1572) Xanthan gum 2 Thickening agent (AG-RHO POL 23/W) Magnesium aluminum silicate (VEEGUM R) 20 Thickening agent 1,2-benzisothiazolin-3-one 2 Biocide (PROXEL GXL) Water 546 Carrier

Example 4

Using the general procedure described in Example 1 above, an aqueous 5 suspension concentrate formulation was prepared from the components summarized in Table 4 below.

Table 4

Component Amount Function (9) Azoxystrobin (98 %) 255 Active ingredient Fatty alcohol 150 Surfactant polyoxyethylene ether (R=Cia; n=15) (ATPLUS MBA13/15; ex Croda) Naphthalene sulfonate formaldehyde polycondensate (MORWET D-425) 20 Surfactant Propylene glycol 60 Anti-freezing agent Silicone antifoaming agent (SAG 1572) 5 Anti-foaming agent Xanthan gum 2 Thickening agent (AG-RHO POL 23/W) Magnesium aluminum silicate (VEEGUM R) 20 Thickening agent 1,2-benzisothiazolin-3-one (PROXEL GXL) 2 Biocide Water 546 Carrier

Example 5

Using the general procedure described in Example 1 above, an aqueous 5 suspension concentrate formulation was prepared from the components summarized in Table 5 below.

Table 5

Component Amount Function (9) Azoxystrobin (98 %) 255 Active ingredient Fatty alcohol polyoxyethylene ether (R= Cis-rich and iso-C11-C14; n=8) 150 Surfactant (GENAPOL X 080; ex Clariant) Naphthalene sulfonate formaldehyde polycondensate (MORVVET D-425) 20 Surfactant Propylene glycol 60 Anti-freezing agent Silicone antifoaming agent (SAG 1572) 5 Anti-foaming agent Xanthan gum 2 Thickening agent (AG-RHO POL 23/W) Magnesium aluminum silicate (VEEGUM R) 20 Thickening agent 1,2-benzisothiazolin-3-one (PROXEL GXL) 2 Biocide Water 546 Carrier

Example 6

Using the general procedure described in Example 1 above, an aqueous 5 suspension concentrate formulation was prepared from the components summarized in Table 6 below.

Table 6

Component Amount Function (9) Azoxystrobin (98 %) 255 Active ingredient Fatty alcohol 150 Surfactant polyoxyethylene ether (R= Cs; n=4) (Berol 840; ex AkzoNobel) Naphthalene sulfonate formaldehyde polycondensate 20 Surfactant (MORVVET D-425) Propylene glycol 60 Anti-freezing agent Silicone antifoaming agent (SAG 1572) 5 Anti-foaming agent Xanthan gum 2 Thickening agent (AG-RHO POL 23/W) Magnesium aluminum silicate (VEEGUM R) 20 Thickening agent 1,2-benzisothiazolin-3-one (PROXEL GXL) 2 Biocide Water 546 Carrier

Example 7

Using the general procedure described in Example 1 above, an aqueous suspension concentrate formulation was prepared from the components summarized in Table 7 below.

Table 7

Component Amount Function (9) Pyraclostrobin (98%) 255 Active ingredient Fatty alcohol 180 Surfactant polyoxyethylene ether (R=C16 to Cis; n=25) (GENAPOL T 250 P; ex Clariant) Naphthalene sulfonate formaldehyde polycondensate (MORVVET D-425) 20 Surfactant Propylene glycol 60 Anti-freezing agent Silicone antifoaming agent (SAG 1572) 5 Anti-foaming agent Xanthan gum 2 Thickening agent (AG-RHO POL 23/W) Magnesium aluminum silicate (VEEGUM R) 20 Thickening agent 1,2-benzisothiazolin-3-one (PROXEL GXL) 2 Biocide Water 516 Carrier

Example 8

Using the general procedure described in Example 1 above, an aqueous suspension concentrate formulation was prepared from the components 5 summarized in Table 8 below.

Table 8

Component Amount Function (9) Picoxystrobin (98%) 245 Active ingredient Fatty alcohol 120 Surfactant polyoxyethylene ether (R=C16 to C18, n=20) (GENAPOL 1200 P; ex Clariant) Naphthalene sulfonate formaldehyde polycondensate (MORVVET D-425) 20 Surfactant Propylene glycol 60 Anti-freezing agent Silicone antifoaming agent (SAG 1572) 5 Anti-foaming agent Xanthan gum 2 Thickening agent (AG-RHO POL 23/W) Magnesium aluminum silicate (VEEGUM R) 20 Thickening agent 1,2-benzisothiazolin-3-one (PROXEL GXL) 2 Biocide Water 586 Carrier Comparative Example 1 Using the general procedure described in Example 1 above, an aqueous 5 suspension concentrate formulation was prepared from the components summarized in Table 9 below.

Table 9

Component Amount Function (9) Azoxystrobin (98 %) 255 Active ingredient Naphthalene sulfonate formaldehyde polycondensate 20 Surfactant (MORVVET D-425) Propylene glycol 60 Anti-freezing agent Silicone antifoaming agent (SAG 1572) 5 Anti-foaming agent Xanthan gum 2 Thickening agent (AG-RHO POL 23/W) Magnesium aluminum silicate (VEEGUM R) 20 Thickening agent 1,2-benzisothiazolin-3-one (PROXEL GXL) 2 Biocide Water 696 Carrier Comparative Example 2 Using the general procedure described in Example 1 above, an aqueous 5 suspension concentrate formulation was prepared from the components summarized in Table 10 below.

Table 10

Component Amount Function (9) Azoxystrobin (98 %) 255 Active ingredient tristyrylphenol polyoxyethylene ether (SOPROPHOR BSU; ex Solvay) 150 Sufactant Naphthalene sulfonate formaldehyde polycondensate (MORVVET D-425) 20 Surfactant Propylene glycol 60 Anti-freezing agent Silicone antifoaming agent (SAG 1572) 5 Anti-foaming agent Xanthan gum 2 Thickening agent (AG-RHO POL 23/W) Magnesium aluminum silicate (VEEGUM R) 20 Thickening agent 1,2-benzisothiazolin-3-one (PROXEL GXL) 2 Biocide Water 546 Carrier Comparative Example 3 Using the general procedure described in Example 1 above, an aqueous 5 suspension concentrate formulation was prepared from the components summarized in Table 11 below.

Table 11

Component Amount Function (9) Azoxystrobin (98 %) 255 Active ingredient polycarboxylate 150 Sufactant (ATLOX 4913; ex Croda) Naphthalene sulfonate formaldehyde polycondensate (MORVVET D-425) 20 Surfactant Propylene glycol 60 Anti-freezing agent Silicone antifoaming agent (SAG 1572) 5 Anti-foaming agent Xanthan gum 2 Thickening agent (AG-RHO POL 23/VV) Magnesium aluminum silicate (VEEGUM R) 20 Thickening agent 1,2-benzisothiazolin-3-one (PROXEL GXL) 2 Biocide Water 546 Carrier Comparative Example 4 Using the general procedure described in Example 1 above, an aqueous suspension concentrate formulation was prepared from the components summarized in Table 12 below.

Table 12

Component Amount Function (9) Pyraclostrobin (98%) 255 Active ingredient Naphthalene sulfonate formaldehyde polycondensate (MORWET D-425) 20 Surfactant Propylene glycol 60 Anti-freezing agent Silicone antifoaming agent (SAG 1572) 5 Anti-foaming agent Xanthan gum 2 Thickening agent (AG-RHO POL 23/W) Magnesium aluminum silicate (VEEGUM R) 20 Thickening agent 1,2-benzisothiazolin-3-one (PROXEL GXL) 2 Biocide Water 696 Carrier Comparative Example 5 Using the general procedure described in Example 1 above, an aqueous 5 suspension concentrate formulation was prepared from the components summarized in Table 13 below.

Table 13

Component Amount Function (9) Picoxystrobin (98%) 245 Active ingredient Naphthalene sulfonate formaldehyde polycondensate 20 Surfactant (MORVVET D-425) Propylene glycol 60 Anti-freezing agent Silicone antifoaming agent 5 Anti-foaming agent (SAG 1572) Xanthan gum 2 Thickening agent (AG-RHO POL 23/VV) Magnesium aluminum silicate (VEEGUM R) 20 Thickening agent 1,2-benzisothiazolin-3-one 2 Biocide (PROXEL GXL) Water 706 Carrier

Example 9

Field experiment: control of cucumber powdery mildew Experiments were conducted to test the efficacy of the formulations of Examples 1 to 6 and Comparative Examples 1 to 3 in the control of powdery mildew on Jinchun 4 cucumber plants.

57 plots, each having an area of 10 m2 were prepared. Each plot was planted with 25 cucumber plants. After the cucumber plants had emerged and at the early io stage of powdery mildew infestation, the plants in each of 56 plots were sprayed with one of the formulations of Examples 1 to 6 and Comparative Examples 1 to 3 at a rate of 70 ml/acre or 90 ml/acre using a 3WBD-16 knapsack electric sprayer, giving 3 replications of each formulation applied at each of the aforementioned rates. Each treatment was repeated 4 times.

One plot was treated with water as a control.

The formulation was applied to both the front and the back sides of the leaves of the cucumber plants.

The morbidity of the cucumber powdery mildew was investigated 7 days after treatment. The effectiveness of the control of powdery mildew was analysed as 20 follows: spots in each plot were selected at random. 2 plants at each spot were investigated. All the leaves of each plant were inspected visually to determine the level of powdery mildew infestation. The level of infestation was graded as follows: Grade 0: no disease; Grade 1: the diseased area occupied at most 5% of the total leaf area; Grade 3: the diseased area occupied 6%-10% of the total leaf area; Grade 5: the diseased area occupied 11%-20% of the total leaf area; Grade 7: the diseased area occupied 21%-40% of the total leaf area; Grade 9: the diseased area occupied at least 40% of the total leaf area.

The efficacy of the treatments in controlling the powdery mildew infestation was determined as follows: Disease Index = (n x V) x 100 N x 9 where: n = number of diseased leaves at a grade, V = value at the corresponding grade; N = total number of leaves investigated.

Control effect (1)/0) = GK-PT x 100

CK

where: CK = Disease Index of the control plot after treatment with water; PT = Disease Index of plot after treatment with formulation.

The results are summarized in Table 14 below.

Table 14

Agent treatment Preparation Disease index Control effect dosage (%) (ml/acre) Example 1 70 0.62 86.10 0.23 94.84 Example 2 70 0.64 85.65 0.33 92.60 Example 3 70 0.6 86.55 0.28 93.72 Example 4 70 0.58 87.00 0.25 94.39 Example 5 70 0.88 80.27 0.62 86.10 Example 6 70 0.85 80.94 0.56 87.44 Comparative 70 1.21 72.87

Example 1

0.92 79.37 Comparative 70 1.25 71.97

Example 2

0.94 78.92 Comparative 70 1.32 70.40

Example 3

0.96 78.48 Clear water - 4.46 -control Referring to Table 14, it can be seen that the aqueous suspension formulations of Examples 1 to 6 employing azoxystrobin in combination with a fatty alcohol polyoxyethylene ether provided a high level of control of the powdery mildew infestation at both the application rates tested. In contrast, the formulations of the Comparative Examples 1 to 3, which did not employ a fatty alcohol polyoxyethylene ether performed significantly worse and provided a significantly lower level of control of the powdery mildew infestation.

The aqueous suspension antimicrobial composition of the present invention io exhibited a significantly improved biological activity In particular, a combination of azoxystrobin and a fatty alcohol polyoxyethylene ether surfactant exhibited a synergistic effect in improving the biological activity of azoxystrobin.

In addition, at the later stage of the experiment, it was also found that the total amount of cucumbers produced in the plots treated in accordance with the present invention was higher by at least 8% on average, compared with the total amount of cucumbers produced in the plots treated with the compositions of the comparative examples. It was also found that the amount of cucumbers produced in the plots treated in accordance with the present invention was higher by at least 6% compared with other plots without powdery mildew infestations (controlled by using other fungicidal agents). This demonstrates that the techniques of the present invention has the effect on increasing the yield of cucumbers.

Example 10

Field experiment: control of Powdery Mildew on Wheat Experiments were conducted to test the efficacy of the formulations of Examples 7 to 8 and Comparative Examples 4 and 5 in the control of powdery mildew on Ningmai wheat plants.

Plots having an area of 25 m2 were prepared and sown with Ningmai wheat plants. After the wheat plants had emerged and at the early stage of powdery mildew infestation, the plants in each plot were sprayed with one of the formulations of Examples 7 to 8 and Comparative Examples 4 and 5 at one of the dosages indicated in Table 15 below using a 3WBD-16 knapsack electric sprayer Each treatment was repeated 4 times.

One plot was treated with water as a control.

The morbidity of the wheat powdery mildew was investigated 7 days after treatment. The effectiveness of the control of powdery mildew was analysed as follows: Each plot was diagonally fixed at 5 spots, each spot having an area of 0.25 m2.

1 to 5 leaves at the jointing stage at the base of each wheat plant in each spot were investigated and the stage leaves were investigated after treating.

The level of infestation was graded as follows: Grade 0: no disease; Grade 1: the diseased area occupied at most 5% of the total leaf area; Grade 3: the diseased area occupied 6%-15% of the total leaf area; Grade 5: the diseased area occupied 16%-25% of the total leaf area; Grade 7: the diseased area occupied 26%-50% of the total leaf area; Grade 9: the diseased area occupied at least 50% of the total leaf area.

Control effect (%) = CK -PT x 100

CK

The results are summarized in Table 15 below.

Table 15

Agent treatment Preparation Disease index Control effect dosage (0k) (ml/acre) Example 7 40 6.12 63.61 1.45 91.38 Example 8 20 5.75 65.81 1.08 93.58 Corn parative 40 8.27 50.83

Example 4

4.24 74.79 Corn parative 20 7.53 55.23

Example 5

3.18 81.09 Clear water control 16.82 Referring to Table 15 above, it can be seen that the aqueous suspension formulations of Examples 7 to 8 employing Pyraclostrobin or Picoxystrobin in combination with a fatty alcohol polyoxyethylene ether provided a high level of control of the powdery mildew infestation at both the application rates tested. In contrast, the formulations of the Comparative Examples 4 and 5, which did not employ a fatty alcohol polyoxyethylene ether, performed significantly worse and provided a significantly lower level of control of the powdery mildew infestation.

Claims

CLAIMS1. An antimicrobial composition comprising: a)a strobilurin fungicide; and b)at least one fatty alcohol polyoxyethylene ether.
2. The antimicrobial composition according to claim 1, further comprising: c) optionally one or more other agrochemically acceptable surfactants; and d) water.
3. The antimicrobial composition according to either of claims 1 or 2, wherein the strobilurin fungicide is selected from the methoxyacrylate strobilurin fungicides, the methoxycarbanilate strobilurin fungicides, the methoxyiminoacetamide strobilurin fungicides, and the methoxyiminoacetate strobilurin fungicides.
4. The antimicrobial composition according to claim 3, wherein the strobilurin fungicide is selected from fluoxastrobin, mandestrobin, pyribencarb, azoxystrobin, zo bifujunzhi, coumoxystrobin, enoxastrobin, flufenoxystrobin, jiaxiangjunzhi, picoxystrobin, pyraoxystrobin, pyraclostrobin, pyrametostrobin, triclopyricarb, dimoxystrobin, fenaminstrobin, metominostrobin, orysastrobin, kresoxim-methyl, trifloxystrobin and mixtures thereof.
5. The antimicrobial composition according to any preceding claim, wherein the strobilurin fungicide comprises azoxystrobin, picoxystrobin, pyroclostrobin or a mixture thereof.
6. The antimicrobial composition according to any preceding claim, wherein the fatty alcohol polyoxyethylene ether is represented by the following general formula: R-0-(CH2-CH2-0)n-H (I) in which R represents an alkyl group and n is the ethylene oxide (EO) number, wherein R is straight chain or branched chain.
7. The antimicrobial composition according to claim 6, wherein R is an alkyl group having from 2 to 25 carbon atoms.
8. The antimicrobial composition according to either of claims 6 or 7, wherein n is from 2 to 50
9. The antimicrobial composition according to any of claims 6 to 8, wherein the fatty alcohol ether polyoxyethylene ether has R from C4 to C20 alkyl group and n is 20 from 4 to 40.
10. The antimicrobial composition according to any preceding claim, wherein the strobilurin fungicide and the fatty alcohol ether polyoxyethylene are present in a ratio of from 10:1 to 1:10.
11. The antimicrobial composition according to any preceding, wherein the composition is an aqueous suspension.
12. The antimicrobial composition according to claim 11, wherein the strobilurin fungicide is present in the aqueous suspension as particles having an average io particle size of below 5pm.
13. A method for controlling microbial infestations in plants, the method comprising applying to the plants, plant parts, plant propagation materials or their locus one or more strobilurin fungicides and a fatty alcohol polyoxyethylene ether.
14, The method according to claim 13, wherein the strobilurin fungicide and the fatty alcohol ether polyoxyethylene are employed in a ratio of from 10:1 to 1:10.
15. The method according to either of claims 13 or 14, wherein the strobilurin fungicide and the fatty alcohol ether polyoxyethylene are applied separately and/or together.
16. The method according to claim 15, wherein a composition according to any of claims 1 to 12 is employed.
17. The method according to any of claims 13 to 16, wherein the microbial infestation being controlled is one or more of Plasmopara viticola, Erysiphales spp., Phytophthora spp., Pseudo peroNospora cubeNsis, PeroNospora brassicae, ErysiphegramiNis, SclerotiNia sclerotiorum, PyreNophorateres, VeNturia Nashicola, VeNturia iNaequafis, Colletotrichum lageNarium, AlterNaria mafi, AlterNaria solaNi and RhizoctoNie solaNi.
18. The use of one or more strobilurin fungicides and a fatty alcohol polyoxyethylene ether to control microbial infestations.
19. Use of a fatty alcohol polyoxyethylene ether to increase the antimicrobial activity of a strobilurin fungicide.
20. Use of a combination of a strobilurin fungicide and a fatty alcohol polyoxyethylene ether to increase the yield of crop plants.
21. An aqueous suspension antimicrobial composition comprising: a)a strobilurin fungicide; b)at least one C2 -C25 fatty alcohol polyoxyethylene ether having an average EO number of 5-50, c) optionally one Or more other agrochemically acceptable surfactants; and d)water.
22 An aqueous suspension antimicrobial composition comprising: a) 50 g/L to 300 g/L of one or more strobilurin fungicides; b) 25 g/L to 250 g/L of at least one C2 -C25 fatty alcohol polyoxyethylene ether having an average EO number of from 5 to 50; C) 0 g/L to 200 g/L of one or more other agrochemically acceptable surfactants; and d) water making up to 1 L.
23. An aqueous suspension antimicrobial composition comprising: a) 50 g/L to 300 g/L of one or more strobilurin fungicides; b) 25 g/L to 250 g/L of at least one C10-C20 fatty alcohol polyoxyethylene ether having an average E0 number of from 5 to 50; c) 0 g/L to 200 g/L of one or more other agrochemically acceptable surfactants; and d) water making up to 1 L.
24. The composition according to any of claims 21 to 23, wherein the strobilurin fungicide comprises azoxystrobin, picoxystrobin and/or pyraclostrobin.