WO2020121345A1

WO2020121345A1 - Oil dispersion containing fluindapyr and use thereof as fungicide in crop plants

Info

Publication number: WO2020121345A1
Application number: PCT/IT2018/000161
Authority: WO
Inventors: Elisa GALIMBERTI; Claudio DACARRO; Paolo Bellandi
Original assignee: Isagro S.P.A.
Priority date: 2018-12-14
Filing date: 2018-12-14
Publication date: 2020-06-18

Abstract

The present invention relates to an oil dispersion comprising: at least the active agrochemical ingredient fluindapyr suspended in a finely divided form in an oil phase; an emulsifying system comprising at least one nonionic surfactant; at least one rheological modifier. The present invention also relates to the use of the aforementioned oil dispersion as a fungicide in crop plants.

Description

1

"OIL DISPERSION CONTAINING FLUINDAPYR AND USE THEREOF AS FUNGICIDE IN CROP PLANTS"

The present invention relates to an oil dispersion containing fluindapyr and its use as a fungicide in crop plants .

BACKGROUND

Fluindapyr is a succinate dehydrogenase inhibitor (SDHI) , an enzyme linked to the inner mitochondrial membrane that participates in the cellular respiration process .

Inhibitors of this enzyme are used as fungicides in the agricultural field and are known for their high level of biological activity and broad spectrum of action.

In particular, fluindapyr belongs to the class of N-indanyl-pyrazolcarboxamides and is represented by the formula (I) , shown below:

Numerous formulations containing succinate dehydrogenase inhibitors are known in the art for use in the agrochemical field. Such formulations can be in the form of solid or liquid preparations, or in the form of solid suspensions in liquids.

In order to be correctly used, the formulations 2 have to be able to solubilize or disperse, or they have to give rise to stable emulsions when diluted in specific volumes of water. The formulations with the addition of water are in turn applied to crops or soils in which a crop is grown, before or after sowing or germination.

Some agropharmaceutical products are validly used in the form of oil dispersions (OD) , a specific type of liquid agronomic formulation wherein the active agrochemical ingredient is dispersed in oil. Oil dispersions can include further active agrochemical ingredients, solvents and other co-formulants, such as wetting agents, dispersants, rheological modifiers, anti- foaming agents, which allow to improve its stability and make it more suitable for use in agriculture .

Oil dispersions have numerous advantages, such as for example a high level of biological activity due to the presence of the oil itself, which improves the coverage on leaf surfaces . A further advantage is the possibility of obtaining formulations containing unstable active ingredients in an aqueous environment, i.e. substances which in water, for example, react chemically by degrading or give rise to phenomena of physical instability, such as flocculation or crystallization.

However, it is known to the persons skilled in the art that oil dispersions have problems of physical instability over time, such as the loss of homogeneity due to the progressive tendency of active ingredient's particles which are suspended in the oil phase to sediment; due to this instability, the need to re- -3- homogenize the dispersion before use by stirring is well known.

Furthermore, the difficulty in dispersing these formulations when they are diluted in water before practical use is also known.

In consideration of the aforementioned state of the art, there is therefore a need to obtain an oil dispersion, which remains stable and homogeneous over time and which can easily be dispersed in the water used for the agricultural treatment, obtaining an effective agronomic formulation.

DESCRIPTION

The Applicant has found that the aforementioned drawbacks of the state of the art, which will be better illustrated in the following description, can be at least partially overcome by using an oil dispersion containing fluindapyr and certain co-formulants . Such co-formulants allow to obtain oil dispersions containing the active ingredient fluindapyr which are surprisingly stable over time and with which it is possible to efficiently and easily obtain a homogeneous and stable dispersion following dilution with water.

Therefore, a first object of the present invention is an oil dispersion comprising:

a) at least the active agrochemical ingredient fluindapyr suspended in a finely divided form in an oil phase;

b) at least one nonionic emulsifying surfactant; c) at least one rheological modifier.

Fluindapyr is the ISO name of the molecule having chemical formula 3 -difluoromethyl-N- (7-fluoro-l, 1,3- trimethyl -4 - indanyl) - 1-methyl-4 -pyrazolcarboxamide . Preferably, fluindapyr is present in the oil dispersion in an amount within the range from 1% to 70% by weight, more preferably from 3% to 60% by weight, with respect to the weight of said oil dispersion.

The oil dispersion according to the present invention, in addition to fluindapyr, may comprise at least one further active agrochemical ingredient, other than fluindapyr, or a mixture of two or more further active agrochemical ingredients other than fluindapyr.

The term "active agrochemical ingredient" or "agrochemical compound" is intended as an active substance which produces a protective effect against harmful organisms, a conservation effect and/or a control effect of a crop. The active agrochemical ingredients are selected, for example, from: fungicides, insecticides, nematocides, herbicides, phytoprotectors and/or growth regulators. Fungicides are the particularly preferred agrochemical compounds . The other active ingredients can be, for example, fungicides belonging to a selection of chemical classes among :

triazoles;

imidazoles;

strobilurins ;

copper salts;

phthalimides ;

dithiocarbamates ;

chloronitriles ;

acylalanines .

Examples of fungicidal compounds belonging to the class of triazoles that can be included in the oil dispersion are: azaconazole, bitertanol, bromuconazole, cyproconazole , diniconazole, diphenoconazole, epoxiconazole, hexaconazole , etaconazole, fenbuconazole, fluquinconazole, flusilazole, flutriafol, ipconazole, ipfentrifluconazole, mefentrifluconazole, metconazole, myclobutanil , penconazole, propiconazole , prothioconazole, simeconazole, tebuconazole, tetraconazole, triadimefon, triadimenol, triticonazole .

Examples of fungicidal compounds belonging to the class of imidazoles that can be present in the oil dispersion are: imazalyl, oxpoconazole, pefurazoate, prochloraz, triflumizole .

Examples of fungicidal compounds belonging to the class of strobilurins that can be present in the oil dispersion are: azoxystrobin, dimoxystrobin, fluoxastrobine, kresoxim-methyl , methominostrobin, orysastrobine, picoxystrobin, pyraclostrobin, pyrametostrobin, pyraoxostrobin, trifloxystrobin.

Examples of fungicidal compounds belonging to the class of copper salts that can be present in the oil dispersion are: copper hydroxide, tetracopper oxychloride, Bordeaux mixture (copper sulphate neutralized with calcium hydroxide) , copper sulphate, alone or in a mixture thereof .

Examples of fungicidal compounds belonging to the class of phtalimides that can be used in the oil dispersion are: folpet, captan, captafol.

Examples of fungicidal compounds belonging to the class of dithiocarbamates that can be used in the oil dispersion are: febram, maneb, mancozeb, metiram, propineb, thiram, zinc thiazole, zineb, ziram.

An example of fungicidal compounds belonging to the class of chloronitriles that can be used in the oil dispersion is chlorothalonil .

Examples of fungicidal compounds belonging to the class of acylalanines that can be used in the oil dispersion are: benalaxyl, benalaxyl-M, furalaxyl, metalaxyl, metalaxyl-M.

In one embodiment, the at least one further active ingredient is selected from: prothioconazole, tetraconazole, azoxystrobin, copper hydroxide, tetracopper oxychloride, folpet, mancozeb, chlorothalonil, benalaxyl, benalaxyl-M and mixtures thereof .

When the oil dispersion contains one or more further active ingredients, their total concentration (including fluindapyr) is preferably in the range from 1% to 60% by weight, more preferably from 3% to 50%, with respect to the weight of said oil dispersion.

Typically, an oil dispersion is prepared by adding one or more active ingredients together with co formulating compounds to an oil phase maintained under stirring; if necessary, the suspension thus obtained is ground until obtaining particles of active ingredients in the desired, finely divided form.

According to the present invention, preferably, the average particle size of the active ingredient, expressed as Dv50, is equal to or less than 4 pm. Preferably, the average particle size of the active ingredient, expressed as Dv90, is equal to or less than 12 pm.

As is known, the Dv50 index represents the diameter value below which the particles are 50% by volume. The Dv90 index represents the diameter value below which the particles are 90% by volume.

The Dv50 and Dv90 indices can be determined through Dynamic Light Scattering (DLS) measurements.

The active ingredient can be present in the oil dispersion in the form of a dispersed solid, if the solubility in the oil phase is very low, or it can have a dissolved or partially dissolved form if it is soluble or partially soluble in the oil phase.

In general, the oil phase is an organic liquid phase, substantially immiscible with water and can comprise one or more petroleum distillates, such as aromatic hydrocarbons derived from benzene (e.g. toluene, xylene, other alkylated benzenes, naphthalene derivatives, etc.); aliphatic hydrocarbons (e.g. hexane, octane, cyclohexane, etc.), aliphatic or isoparaffinic mineral oils, aromatic and aliphatic hydrocarbon mixtures, vegetable oils (e.g. rapeseed oil, soy bean oil, olive oil, castor oil, linseed oil and the like, and the related esterified derivatives

Ci-Cg) .

The esterified derivatives of vegetable oils can be obtained through the transesterification of vegetable oils with short-chain alcohol, such as methanol, ethanol, butanol and pentanol, or through the esterification of the fatty acid fractions derived from the saponification of vegetable oils with the same alcohols .

Preferably, the oil phase is a vegetable oil or a related esterified derivative Ci~C₆. More preferably, the oil phase is rapeseed oil, even more preferably it is a methyl ester of rapeseed oil.

The oil phase is present in the oil dispersion in an amount suitable to obtain the total desired oil dispersion volume. Generally, the oil phase is present in the oil dispersion in a total amount within the range from 1% to 90% by weight, more preferably from 20% to 40% by weight, with respect to the weight of said oil dispersion.

As mentioned above, the Applicant has found that specific co-formulants , such as at least one nonionic surfactant and at least one rheological modifier, allow to obtain an oil dispersion containing fluindapyr which is surprisingly stable over time and has a high propensity to form a homogeneous and stable dispersion following dilution with water.

The nonionic surfactant mainly performs the function of emulsifier, i.e. its presence in the oil dispersion promotes the emulsification of the oil phase with the water used for its dilution, thus making the final, ready to use formulation homogeneous. Preferably, the emulsifying effect is obtained by using an emulsifying system comprising said at least one nonionic surfactant in combination with at least one second anionic surfactant.

Preferably, the at least one nonionic emulsifying surfactant is selected from: ethoxylated block copolymers, etho-propoxylated block copolymers, ethoxylated tristyrylphenols , etho-propoxylated tristyrylphenols , ethoxylated tristyrylphenols phosphates (acid form) , ethoxylated tristyrylphenols sulphates (acid form) , sorbitan monolaurates, ethoxylated sorbitan monolaurates, sorbitan mono- oleates, ethoxylated sorbitan mono-oleates, ethoxylated vegetable oil, ethoxylated fatty alcohols, organosilicon compounds and mixtures thereof. More preferably the at least one nonionic surfactant is a etho-propoxylated tristyrylphenol .

Preferably, the at least one nonionic emulsifying surfactant is present in the oil dispersion in an overall amount comprised in the range from 5% to 40% by weight, more preferably from 7% to 25% by weight, with respect to the weight of said oil dispersion.

Preferably, said at least one anionic surfactant is selected from: ethoxylated tristyrylphenol phosphates (salt form) , ethoxylated tristyrylphenol sulphates (salt form) , calcium dodecyl benzene sulphonate and mixtures thereof. More preferably, said at least one anionic surfactant is selected from: calcium dodecyl benzene sulphonate and ethoxylated tristyrylphenol phosphates (salt form) .

If present, said at least one anionic surfactant is contained in the oil dispersion in a total amount within the range from 1% to 10% by weight, more preferably from 2% to 5% by weight, with respect to the weight of said oil dispersion.

According to the present invention, the oil dispersion comprises one or more rheological modifiers.

Preferably, the rheological modifier is selected from: clay, modified clay, high surface area silica, cellulose derivatives, hydrogenated castor oil and mixtures thereof. Preferably, the rheological modifier is a clay, such as atapulgite or bentonite, or is a high surface area silica.

Preferably, the rheological modifier is present in the oil dispersion in a total amount within the range from 0.1% to 10% by weight, more preferably from 0.5% to 5% by weight, with respect to the weight of said oil dispersion.

Optionally, the oil dispersions according to the present invention can comprise further co-formulants other than those mentioned above, such as for example compounds for improving their biological activity, anti-drift agents, penetrating agents, wetting agents, anti-foaming agents, stabilizers, sequestering agents, anti-corrosion agents, spreaders and the like.

The preparation of the above-mentioned oil dispersions can be carried out according to known methods, mixing the components in the desired ratios, without particular limitations in the order in which the components are mixed.

For example, in a first step the active ingredient fluindapyr can be dispersed in oil; in a second step, at least one nonionic surfactant and at least one rheological modifier are added to the suspension obtained in the first step.

According to an alternative process, fluindapyr is added to the mixture containing the oil phase, a nonionic surfactant and a rheological modifier.

In both cases, the suspension thus obtained can then be subjected to grinding until the desired granulometry for the active ingredient particles is obtained.

The oil dispersions according to the present invention exhibit a high level of fungicidal activity and do not show any substantial phytotoxicity towards the crops to which they are applied.

Therefore a further object of the present invention is the use of the above oil dispersions for the control of phytopathogenic fungi in a crop plant .

A further object of the present invention is a method for controlling phytopathogenic fungi in a crop plant which comprises applying at least one effective dose of one of the oil dispersions described above to a crop plant .

Examples of crops of interest are: fruit trees, vegetables and extensive crops, such as rice, wheat and soy .

The oil dispersions according to the present invention can be applied, after adding water, to any part of a plant, for example on leaves, stems, branches and roots, or on the seeds themselves before sowing, or on the soil where the plant will grow.

The oil dispersion according to the present invention can be used to prepare, after dilution in water, a ready to use formulation comprising a suspension of solid particles and an emulsion of the oil phase (so-called suspo-emulsion) . For this purpose, the oil dispersion can comprise other ingredients, such as wetting agents, emulsifying agents, stabilizing agents, etc.. The additional ingredients can be present in the oil dispersion or in the dilution water used to prepare the suspo-emulsion.

Therefore a further object of the present invention is a process for preparing an agronomic formulation, preferably in the form of suspo-emulsion, comprising :

providing at least one oil dispersion according to the present invention,

diluting said oil dispersion with water to obtain said agronomic formulation. Water is added to the oil dispersion in the amount necessary to reach the required volume of agronomic formulation.

The quantity of agronomic formulation to be applied to a crop plant to obtain the desired agrochemical effect may vary depending on various factors such as, for example, the crop, climatic conditions, soil characteristics, the method of application.

In order to better illustrate the invention, the following examples are now provided, which are to be considered illustrative and non-limiting of the invention.

EXAMPLES

Oil dispersions containing fluindapyr

The oil dispersions (OD) n. 1-9 according to the present invention having the compositions shown in Table 1 were prepared.

The commercial products used for the preparation of the aforementioned oil dispersions are as follows:

Amesolv CME, mixture of methyl esters of fatty acids from rapeseed oil;

Soprophor 796/P, etho-propoxylated tristyrylphneol ;

Rhodacal 60/BE, calcium salt of benzene sulphonic acid;

Soprophor FLK, ethoxylated tristyrylphenol phosphate, potassium salt;

Emulson AG/PE, etho-propoxylated block copolymer;

Imbirol OT/NA/70, sodium docusate;

Atlas G-5002L, block copolymer; Atlox Metasperse 550S, acrylic polymer;

Alkamuls T85V, ethoxylated sorbitan trioletate ;

Rhodasurf ID5, isotridecyl ethoxylated alcohol

Attagel 40, atapulgite;

Alkamuls VO2003, ethoxylated fatty alcohol; Alkamuls OR36, ethoxylated castor oil;

BreakThru AF 5503, organosilicon compound, with anti-foaming function;

BreakThru OE 440, organosilicon compound.

Table 1

The oil dispersions n. OD1 - OD9 were subjected to the accelerated stability test according to Cipac MT 46.1, which aims at accelerating the ageing of the product through heating. This test allows to simulate the stability of a formulation after two years of storage at room temperature .

The following procedure was used: a certain amount of formulation (for example 500 mL) was placed in a hermetically sealed container and left in an oven at 54 °C for 14 days. After this time, the container was removed from the oven and left to return to room temperature. It was therefore visually verified that the formulation did not show any phase separation or other phenomena of physical instability, such as flocculation, aggregation or crystalline growth. The chemical stability of the active agrochemical ingredient is also verified, as well as the quality of the dispersion subjected to accelerated stability test, after dilution in water.

All the samples OD1 - OD9 passed the accelerated ageing test, as the oil dispersions remained in a homogeneous state at the end of the heat treatment.

Determination of fungicidal activity against

Septoria nodorum on wheat

Leaves of Abate variety wheat plants, grown in pots in a conditioned environment at 20°C and 70% Relative Humidity (R.H.), were treated by spraying both sides of the leaves with the oil dispersion under examination (see the following Table 2) .

After remaining in the conditioned environment for six days, both sides of the plants' leaves were sprayed with an aqueous suspension of spores of Septoria nodorum (1 ,000,000 spores/cc) .

After spraying, the plants were kept in an environment saturated with humidity and a temperature comprised between 18 and 24 °C for the incubation period of the fungus (2 days) .

At the end of this period, the plants were placed in a greenhouse with 70% R.H. and a temperature of 18- 24 °C for 10-12 days.

After this period of time, the external symptoms of the pathogen appeared, and it was therefore possible to carry out a visual evaluation of the intensity of the infection. The fungicidal activity is expressed as a percentage of reduction, compared to untreated plants (control) , of the leaf area affected by the disease (100 = complete efficacy, 0 = no efficacy) .

The oil dispersion OD3 exhibited excellent control of the disease.

Table 2 shows the results obtained by carrying out the test with the aforementioned oil dispersion.

Table 2

Claims

1. An oil dispersion comprising:

b) at least one nonionic emulsifying surfactant;

c) at least one rheological modifier.

2. The oil dispersion according to claim 1, wherein said fluindapyr is present in an amount within the range from 1% to 70% by weight, more preferably from 3% to 60% by weight, with respect to the weight of said oil dispersion.

3. The oil dispersion according to claim 1, wherein said rheological modifier is selected from: clay, modified clay, silica, cellulose derivatives, hydrogenated castor oil and mixtures thereof; preferably silica, atapulgite, bentonite and mixtures thereof .

4. The oil dispersion according to claim 1, wherein said nonionic emulsifying surfactant is selected from: ethoxylated block copolymers, etho- propoxylated block copolymers, ethoxylated tristyrylphenols , etho-propoxylated tristyrylphenols, ethoxylated tristyrylphenols phosphates (acid form) , ethoxylated tristyrylphenol sulphates (acid form) , sorbitan monolaurates , ethoxylated sorbitan monolaurates , sorbitan mono-oleates , ethoxylated sorbitan mono-oleates, ethoxylated vegetable oil, ethoxylated fatty alcohols, organosilicon compounds and mixtures thereof .

5. The oil dispersion according to claim 1, which comprises an emulsifying system comprising at least one nonionic emulsifying surfactant and at least one anionic surfactant, preferably selected from: ethoxylated tristyrylphenol phosphates (salt form) , ethoxylated tristyrylphenol sulphates (salt form) , calcium dodecyl benzene sulphonate and mixtures thereof, preferably calcium dodecyl benzene sulphonate and ethoxylated tristyrylphenol phosphates (salt form) .

6. The oil dispersion according to claim 1, comprising at least one further active agrochemical ingredient other than fluindapyr selected from: fungicides, insecticides, nematocides, herbicides, phytoprotectors or growth regulators .

7. The oil dispersion according to claim 1, comprising at least one further fungicide other than fluindapyr selected from one of the following classes of compounds :

triazoles;

imidazoles;

strobilurins ;

copper salts;

phthalimides ;

dithiocarbamates ;

chloronitriles ;

acylalanines .

8. The oil dispersion according to claim 1, comprising at least one further fungicide other than fluindapyr selected from the following triazoles: azaconazole, bitertanol, bromuconazole, cyproconazole, diniconazole, diphenoconazole , epoxiconazole, hexaconazole , etaconazole, fenbuconazole, fluquinconazole, flusilazole, flutriafol, ipconazole, ipfentrifluconazole, mefentrifluconazole, metconazole, myclobutanil , penconazole, propiconazole, prothioconazole, simeconazole, tebuconazole, tetraconazole, triadimefon, triadimenol, triticonazole and mixtures thereof .

9. The oil dispersion according to claim 1, comprising at least one additional fungicide other than fluindapyr selected from the following strobilurins : azoxystrobin, dimoxystrobin, fluoxastrobine, kresoxi - methyl, methominostrobin, orysastrobine , picoxystrobin, pyraclostrobin, pyrametostrobin, pyraoxostrobin, trifloxystrobin and mixtures thereof.

10. The oil dispersion according to claim 1, comprising at least one further fungicide other than fluindapyr selected from one of the following compounds: prothioconazole, tetraconazole, azoxystrobin, copper hydroxide, tetracopper oxychloride, folpet, mancozeb, chlorothalonil , benalaxyl, benalaxyl-M and mixtures thereof.

11. The oil dispersion according to claim 1, wherein said at least one nonionic surfactant is present in an overall amount within the range from 5% to 40% by weight, more preferably from 7% to 25% by weight, with respect to the weight of said oil dispersion.

12. The oil dispersion according to claim 5, wherein said anionic surfactant is contained in the oil dispersion in an overall amount within the range from 1% to 10% by weight, more preferably from 2% to 5% by weight, with respect to the weight of said oil dispersion.

13. A process for preparing an agronomic formulation comprising: providing at least one oil dispersion according to claim 1,

diluting said oil dispersion with water to obtain said agronomic formulation.

14. Use of an oil dispersion according to claim 1 as fungicide in a crop plant.

15. A method for controlling phytopathogenic fungi in a crop plant comprising applying at least one effective dose of an oil dispersion according to claim 1 to a crop plant .