IE904236A1 - Fungicide combination having a synergistic effect based on a¹morpholine and a triazole - Google Patents

Abstract

The invention relates to a fungicidal composition with synergistic effect comprising at least one 4-[3-(aryloxyphenyl)-2-methylpropyl]-2,6-dimethylmorpholine (I) and a triazole (II) selected from amongst the triazoles containing tetrahydrofuran, cyclopentane or dioxolane rings, the molar ratio of (I) to (II) preferably being between 0.1 and 10. The invention also relates to the fungicidal preparation based on this composition, and to the method for treating plants, be it in a curative or preventive fashion, with said composition or said preparation.

Description

The invention relates to a fungicide combination for use in plant protection comprising at least one compound from the family of morpholines and at least one compound from the family of triazoles, the fungicide composition comprising the said combination and at least one inert carrier acceptable in agriculture, the process for the preventive or curative 10 treatment of plants using the said fungicide combinations or compositions.

Combinations of this type have already been disclosed, in particular by EP-A-237483, which describes the synergistic combination of fenpropimorph, cis-4-[3-(4-tert-butylphenyl)-2-methylpropyl]-2,6dimethylmorpholine, and propiconazole, 1-[2-(2,4dichlorophenyl) -4-propyl-l, 3-dioxolan-2-ylmethyl ] -1H1,2,4-triazole, or by EP-A-230844, which describes a fungicidal synergistic combination comprising furconazole, (2RS, 5RS:2RS, 5SR)-5-(2,4-dichlorophenyl )-tetrahydro-5-(1H-1,2,4-triazol-l-ylmethyl)-2furyl 2,2,2-trifluoroethyl ether and fenpropimorph.

It is, however, always desirable to find other fungicide combinations and/or to improve those previously known.

Thus, taking into account the prior art which has been discussed above and which, to the knowledge of the filing company, is that which enables the state of the art to be illustrated most completely in accordance with Article 9, paragraph c of the decree of 19th September 1979, No. 79.822, or with regulation 27, paragraph c, of the EPC, it is possible to define the object of the invention in the following way: - to propose other fungicide combinations having a synergistic effect, - to propose improved synergistic fungicide combinations, - to propose fungicide combinations which are useful in the preventive or curative treatment of oidium and eyespot, in particular oidium of Cucurbitaceae, and - to propose a new combination which results from a limited choice made from a virtually infinite number of possibilities and which procures significant advantages which will be better understood in the light of what will be described below.

Thus, completely unexpectedly, the combination notably and surprisingly improves the respective and isolated action of the two active substances for some fungi which are particularly harmful in crops, in particular cucumbers, courgettes and melons, and does so while maintaining a lack of phytotoxicity towards crops. The result is therefore an improvement in the spectrum of activity and a possibility of reducing the respective dose of each active substance used, this latter characteristic being particularly important for readily understandable ecological reasons.

Thus, the combination has a remarkable degree of synergism as this is defined by PML Tammes, Netherlands Journal of Plant Pathology, 70 (1964), p. 7380 in an article entitled Isoboles, a graphic representation of synergism in pesticides, or as defined by Limpel, L.E., P.H. Schuldt and D. Lamont, 1962, Proc. NEWCC 16:48-53, using the equation: XY E = X + Y - 100 where E is the expected percentage inhibition of the growth of the fungus by a mixture of the two fungicides at defined doses, X is the observed percentage inhibition of the growth by the fungicide A at a defined dose, and Y is the observed percentage inhibition of the growth by the fungicide B at a defined dose. When the percentage inhibition observed for the combination is higher than E, there is synergism.

In particular, the combination which is the subject of the present invention has proved particularly effective for controlling: - oxdium in Cucurbitaceae due to several related pathogenic fungi, in particular: * Erysiphe cichoracearum, * Sphaerotheca fuliginea.

These fungi are capable of parasitising the leaves of plants of the family of Cucurbitaceae, in particular melons, cucumbers and courgettes, whether these are cultivated in a greenhouse or in the open air; they develop at the surface of the leaves, from their youngest age and send suckers to the inside which draw off the nutrient elements from the sap to the detriment of the plant cells; the result is a reduction in the growth of said cells and their death and thus a loss of production for the agriculturalist.

Fungi other than oXdium ought to be able to be controlled by the same method, in particular the rusts (Puccinia recondita) and the oidium of other crop plants such as cereals (Erysiphe graminis), vines and fruit trees, or scab of apple and pear trees.

The combination is also valuable because it makes it possible to combat strains of reduced sensitivity (resistant strains) to one or other of the fungicides taken separately.

The invention is defined as: Fungicide combination having a synergistic effect, comprising a mixture of: - at least one 4-[3-(aryloxyphenyl)-2methylpropyl]-2,6-dimethylmorpholine of formula: (I) (Z)p in which: p is an integer from 0 to 3, and Z is a halogen atom or a Cx-C* alkyl, Cx-C2 alkoxy, halo(Cx-Ca)alkyl, halo(Cx-C2)alkoxy, NO2, CN or methylenedioxy group.

Advantageously, the compound is 4-[3-(4chlorophenoxyphenyl)-2-methylpropyl]-2,6dimethylmorpholine and has the following formula: (la) These compounds, which are described in EP-A-262870 of 24th September 1987, can exist in the form of a cis/trans mixture or preferably in the predominantly - more than 70 % or pure - cis form.

Of course, those skilled in the art will easily understand that each stereoisomer can itself resolve into several enantiomers. These are also included in the invention. Preferably, a compound of formula I which is in the predominantly - more than 70 % - cis form will be chosen. at least one triazole of the formula: (II) R in which: R is chosen from the tetrahydrofuran rings of formula: Rx being a hydrogen atom or the 2,2,2trifluoroethoxy or Cx-C2 alkoxy group, R2 being a hydrogen atom or the Cx-C2 alkyl group, and when Rx is a hydrogen atom R2 can be a chlorine or bromine atom, and R3 being the o-p-dichlorophenyl or pchlorophenyl group, or a dioxolane ring of formula: R* being the Cx-C3 alkyl group, and Rs having one of the meanings of R3 or being p—(p-chlorophenoxy)-m-chlorophenyl, or a cyclopentane ring of formula: Re having the meaning indicated above for R3.

The compounds of formula II are described for the tetrahydrofuran rings in European Patent Applications Nos. EP-A-121879, 151084 and 230844.

The compounds of formula II are described for the dioxolane rings in German Patent Application DE-OS2752096 and the compounds of formula II are described for the cyclopentane ring in Belgian Patent Application No. 867245.

The contents of these applications are incorporated by reference in respect of the methods for obtaining these compounds.

Preferably, the compounds which will be used 15 are the compounds having a tetrahydrofuran ring where Rx is the 2,2,2-trifluoroethoxy group or Rx is a hydrogen atom and R2 a bromine atom, R3 in all cases being the o,p-dichlorophenyl group, or the compounds having a dioxolane ring where R4 is the n-propyl or ethyl group, Rs being the 2,4-dichlorophenyl group.

As in the case of the morpholines, the triazoles can exist in various isomeric, diastereisomeric and/or enantiomeric forms.

Preferably, in the case of the abovementioned preferred dioxolanes, R4 is predominantly or solely on the same side of the plane as the CH2-triazole, and in the case of tetrahydrofuran where Rj is H and Rx is 2,2,2-trifluoroethoxy or C!-C2 alkoxy, this group Rx is predominantly or solely on the same side of the plane as the CH2-triazole; similarly, in the case where R2 is Br or Cl, this group is predominantly or solely on the same side of the plane as the triazole. Thus, the preferred form is the predominantly or purely cis form.

These forms can, of course, be resolved into enantiomers, which are also part of the invention.

According to a preferred embodiment, the molar ratio of I to II is between 0.1 and 10, preferably between 0.2 and 5 and still more advantageously between 0.4 and 2.5.

The invention also relates to the use of the combination according to the invention for both preventive and curative combating of fungi. The term preventive is understood to mean the treatment of plants before the start of, and to prevent, an infection.

Amongst the fungi which can be controlled by the combination according to the invention, the following may be mentioned: the fungi responsible for oidium (Erysiphe. Cichoracearum, Sphaerotheca fuliqinea. and other organisms of the genera Ervsiphe. such as Ervsiphe graminis. Podosphoera. Uncinula.

Venturia and Puccinia such as Puccinia recondita.

The combinations according to the invention are rarely used on their own for their use in practise. Most frequently they form part of compositions. These compositions, which can be used for the protection of plants against fungal diseases, contain, as active substance, a combination according to the invention as described above, in combination with solid or liquid carriers acceptable in agriculture and, optionally, surfactants, also acceptable in agriculture. In particular, the inert and customary carriers and the customary surfactants can be used.

These compositions usually contain between 0.5 and 95 % of compound according to the invention.

In the present description, the term 15 carrier is used to denote an organic or inorganic, natural or synthetic material with which the active substance is combined to facilitate its application to the plant, to the grains or to the soil. This carrier is therefore generally inert and it must be agriculturally acceptable, in particular on the treated plant. The carrier can be solid (clays, natural or synthetic silicates, silica, resins, waxes, solid fertilizers, etc.) or liquid (water, alcohols, ketones, petroleum fractions, aromatic or paraffin hydrocarbons, chlorinated hydrocarbons, liquefied gases, etc.).

The surfactant can be an emulsifier, dispersant or wetting agent of the ionic or nonionic type. The following may be mentioned for example: salts of polyacrylic acids, salts of lignosulphonic acids, salts of phenolsulphonic acids or naphthalenesulphonic acids, polycondensates of ethylene oxide with fatty alcohols or with fatty acids or with fatty amines, substituted phenols (in particular alkylphenols or arylphenols), the salts of sulphosuccinic acid esters, taurine derivatives (in particular alkyl taurates), phosphoric esters of alcohols or of polycondensates of ethylene oxide with phenols. The presence of at least one surfactant is generally indispensable if the active substance and/or the inert carrier are not soluble in water and water is the vehicle for application.

For their application, the combinations according to the invention are therefore generally in the form of compositions; these compositions according to the invention are themselves in fairly diverse solid or liquid forms.

The following may be mentioned as forms of solid compositions: powders for dusting or dispersion (having a content of compound of formula (I) which can be up to 100 %) and granules, in particular those obtained by extrusion, by compacting, by impregnation of a granulated carrier or by granulation from a powder (the content of compound of formula (I) in these granules being between 1 and 80 % for the latter cases).

The following may be mentioned as forms of liquid compositions or compositions intended to constitute liquid compositions upon application: solutions, in particular water-soluble concentrates, emulsifiable concentrates, emulsions, concentrated suspensions, aerosols, wettable powders (or sprayable powder) and pastes.

The emsulifiable or soluble concentrates most frequently comprise 10 to 80 % of active substance, the emulsions or solutions ready for application containing, for their part, 0.01 to 20 % of active 10 substance.

These compositions may also contain other ingredients of any type, such as, for example, thixotropic colloids, penetration agents, stabilisers, sequestering agents, etc., as well as other known active substances having pesticidal properties (in particular insecticides or fungicides) or properties promoting plant growth (in particular fertilisers) or plant growth-regulating properties. More generally, the compounds according to the invention can be combined with any of the solid or liquid additives corresponding to the customary formulation techniques.

For example, in addition to the solvent, the emulsifiable concentrates can contain, when necessary, to 20 % of appropriate additives, such as stabilisers, surfactants, penetration agents, corrosion inhibitors, colorants or the abovementioned adhesives.

The invention also relates to a method for combating or preventing fungal diseases, characterised in that an effective dose of the combination according to the invention is applied to the green foliage of plants.

Preferably, the effective dose will be 5 between 5 and 1000 g/ha, this dose being dependent on the plant treated, the degree of infestation and the climatic conditions.

Advantageously, this dose will be between 10 and 500 g/ha.

Amongst the plants suitable for the treatment according to the invention, the following may be mentioned more particularly: * vegetable crops such as cucumbers, spinach, black salsify, tomatoes, pease and beet; * arboricultural crops, such as apple trees, pear trees, walnut trees and, more generally, stone-fruits, and vines; and * cereal crops such as wheat and barley.

The invention will now be described with reference to specific examples of implementation which are of course given solely by way of illustration and in no way may limit the scope of the invention.

For these trials, the triazole (a) is either (2RS, 5RS)-5-(2,4-dichlorophenyl)-tetrahydro-5-(1H25 1,2,4-triazol-l-ylmethyl)-2-furyl 2,2,2-trifluoroethyl ether in the form of a suspension at a concentration of 250 g/1 or l-[4-bromo-2-(2,4-dichlorophenyl)tetrahydro-2-furanylmethylJ-1H-1,2,4-triazole in the form of a suspension at a concentration of 200 g/1 and the morpholine (b) is 4-[3-(4-chlorophenoxyphenyl)-2methylpropyl]-2,6-dimethylmorpholine and is in the form of emulsifiable concentrate containing 500 g/1.

Trials with the triazole (2RS, 5RS1-5-(2.4dichlorophenvl)-tetrahvdro-5-(1H-1.2.4-triazol-lvlmethvll-2-furvl 2.2.2-trifluoroethyl ether The two liquids are mixed in an atomiser so as to obtain doses of 15 g/ha of a) and 25 g/ha of b), taking account of the fact that spraying permits an application of 1000 1/ha of liquid.

Cucumber or courgette or charentais melon plants on a block of peat are planted out (the infection of the plants by oidium appeared after planting out on an undetermined date depending on the climatic conditions and in an entirely natural manner) into 16 plots (4 repeats of 4 plots) of a set number of plants, one plot being untreated in each repeat.

* Example 1: Charentais melons infected with Erysiphe c ichor acearum (oidium) are sprayed with the mixture indicated above, at regular intervals, every 8 to 10 days after planting out.

Readings are made ten days after the second spraying and seven days after the fourth.

The results are indicated below.

- First readings» (10 days after the second spraying): The results are indicated as percentage reduction in the diseased foliar surface area relative to the untreated control: (a) on its own at 15 g/ha 84 (b) on its own at 25 g/ha 92 (a) + (b) 99 (7 days after the fourth - Second reading: spraying): (a) on its own at 15 g/ha 12 (b) on its own at 25 g/ha 11 (a) + (b) 52 * Example 2: Courgettes of the diamond variety infected with Erysiphe cichoracearum (oidium) are sprayed with the mixture indicated above, at regular intervals every ten days after planting out.

Readings are made five days after the fourth treatment and five days after the fifth treatment.

As in Example 1, the percentage reduction in diseased foliar surface area relative to the untreated control is observed.

- First readings: (5 days after the fourth treatment): (a) on its own at 15 g/ha 19 (b) on its own at 25 g/ha 34.6 (a) + (b) 72.1 treatment): - Second readings: (5 days after the fifth 26.4 67.3 (a) on its own at 15 g/ha (b) on its own at 25 g/ha (a) + (b) * Example 3: Cucumbers of the Rochet variety infected with Erysiphe cichoracearum (oxdium) are sprayed with the mixture indicated above, at regular intervals every fourteen days after planting out.

Readings are made four days after the third 10 treatment in two different ways: 1) Percentage reduction in diseased foliar surface area, and 2) percentage reduction in the number of diseased leaves. 1) Foliar surface area: (a) on its own at 15 g/ha 45 (*>) on its own at 25 g/ha 24 (a) + (b) 71 2) Number of leaves: 20 (a) on its own at 15 g/ha 46 (b) on its own at 25 g/ha 30 (a) + (b) 72 ♦Example 4: Cucumbers of the Brunex variety infected 25 with Erysiphe cichoracearum (oidium) are sprayed with the mixture indicated above, at regular intervals every 8 to 10 days after planting out.

Readings are made five days after the third treatment and twelve days after the the fifth, tenth and fifteenth leaf fourth treatment on starting from the end.

- First readings: (5 days after the third treatment): (a) on its own at 15 g/ha 53 (b) on its own at 25 g/ha 63 (a) + (b) 96 - Second readings: (12 days after the fourth treatment): 5th leaf 10th leaf 15th leaf (a) on its own at 15 g/ha 34 38 44 (b) on its own at 25 g/ha 59 61 45 (a) + (b) 94 88 92 Conclusion: These results clearly show the significant degree of synergism obtained with the combination according to the invention.

Trials with the triazole l-f4-bromo-2-(2,4dichlorophenvl1-tetrahvdro-2-furanvlmethvl1-1H-1.2.4triazole Example 5 Winter wheat of the Avalon variety, sown in autumn, was treated at the opening stage of the final foliar sheath by foliar spraying with one of the slurries below: A) Compound (b), in the form of a 500 g/1 concentrated suspension diluted in water, in a dose of 200 g of active substance/ha B) Triazole (a), in the form of a 200 g/1 concentrated suspension diluted in water, in a dose of 200 g of active substance/ha C) Compounds (b) and (a), mixed in the atomiser (tank-mix) so as to obtain 200 g (a) + 200 g (b) /ha days after the treatment, the percentage of leaves attacked by oxdium (Erysiphe graminis) was observed considering the last leaf below the ear.

The results given below are obtained: Percentage of diseased leaves A 100 B 37 C 16 A remarkable synergism is therefore observed during the simultaneous action of the two compounds.

Example 6 Winter barley, of the ΤΗέβέβ variety, sown in autumn, was treated at the 3 node” stage and at the flowering stage by foliar spraying with one of the following slurries (A) Compound (b) in the form of 500 g/1 concentrated suspension diluted in water, at a dose of 100 g of active substance/ha (B) Compound (b) in the form of 500 g/1 concentrated suspension diluted in water, at a dose of 200 g of active substance/ha C) Compound (a) in the form of 200 g/1 5 concentrated suspension diluted in water, at a dose of 200 g of active substance/ha (D) Compounds (a) and (b) mixed in the atomiser (tank-mix) so as to obtain 100 g (b) + 200 g (a) (E) Compounds (a) and (b) mixed in the atomiser (tank-mix) so as to obtain 200 g (b) + 200 g (a) days after the second treatment the percentage of leaves attacked by brown rust (Puccinia recondita) is observed considering the second leaf below the ear.

The following results are obtained: Percentage of diseased leaves A 100 B 100 C 37 D 17 E 16 A remarkable synergism is therefore observed during the simultaneous action of the two compounds.

Claims (13)

1) A fungicide combination containing a mixture of: - at least one 4-[3-(aryloxyphenyl)-25 methylpropyl]-2,6-dimethylmorpholine of formula: in which: p is an integer from 0 to 3, and Z is a halogen atom or a Cx-C 4 alkyl, Cx-C 2 10 alkoxy, halo(Cx-C 2 )alkyl, halo(Cx-C 2 )alkoxy, N0 2 , CN or methylenedioxy group, and - at least one triazole of the formula: R (II) in which: R is chosen from the tetrahydrofuran rings of formula: Rx being a hydrogen atom or the 2,2,2IE 904236 trifluoroethoxy or C x -C2 alkoxy group, R2 being a hydrogen atom or the C x -C 2 alkyl group, and when R x is a hydrogen atom R 2 can be a chlorine or bromine atom, and 5 R 3 being the o-p-dichlorophenyl or pchlorophenyl group, or a dioxolane ring of formula: R A being the C x -C 3 alkyl group, and R 5 having one of the meanings of R 3 or being 10 p- (p-chlorophenoxy)-m-chlorophenyl, or a cyclopentane ring of formula: Ra having the meaning indicated above for R 3 .

2. ) The combination as claimed in claim 1, wherein the morpholine I is 4-[3-(4-chlorophenoxy15 phenyl)-2-methylpropyl]-2,6-dimethylmorpholine and has the following formula: (la) ce

3. ) The combination as claimed in either of claims 1 or 2, wherein the compound I is in the predominantly - more than 70 % - cis form.

4. ) The combination as claimed in claim 1, wherein the triazole of formula (II) is such that it is chosen from those having: - a tetrahydrofuran ring where R t is the 2,2,2-trifluoroethoxy group or Ri is a hydrogen atom and R 2 a bromine atom, R 3 in all cases being the o,pdichlorophenyl group, - or the compounds having a dioxolane ring where R 4 is the n-propyl or ethyl group, R 3 being the 2,4-dichlorophenyl group.

5. ) The combination as claimed in claim 4, wherein the triazoles are in the predominantly cis form.

6. ) claims 1 to 5, 0.1 and 10. The combination as claimed in one of wherein the molar ratio I:II is between

7. ) The combination as claimed in claim 6, wherein the molar ratio I:II is between 0.2 and 5.

8. ) A fungicide composition containing, as active substance, 0.5 to 95 % by weight of the combination as claimed in one of claims 1 to 7, in combination with solid or liquid carriers acceptable in agriculture and/or surfactants, also acceptable in agriculture.

9. ) A method for combating or preventing fungal diseases, which comprises applying an effective dose of a combination or a composition as claimed in one of claims 1 to 8 to the green foliage of plants.

10. ) The method as claimed in claim 9, wherein the combination is applied in an amount of 5 to 1000 g/ha. substant ia substantia preventing described

11. ) A fungicide combination according to claim 1, lly as hereinbefore described and exemplified.

12. ) A fungicide composition according to claim 8, lly as hereinbefore described.

13. ) A method according to claim 9. for combating or fungal diseases, substantially as hereinbefore and exemplified.