Fungicidal compositions comprising a carboxamide

Abstract

A method of controlling phytopathogenic diseases on useful plants or on propagation material thereof, which comprises applying to the useful plants, the locus thereof or propagation material thereof a combination of components (A) and (B) in a synergistically effective amount, wherein component (A) is a compound of formula I compound of formula I ##STR00001## wherein R is hydrogen or methoxy; Q is ##STR00002## R.sub.1 is hydrogen, halogen or C.sub.1-C.sub.6alkyl; R.sub.2 is hydrogen, halogen, C.sub.1-C.sub.6alkyl, C.sub.2-C.sub.6alkenyl, C.sub.3-C.sub.6alkinyl, C.sub.3-C.sub.6cycloalkyl-C.sub.3-C.sub.6alkinyl, halophenoxy, halophenyl-C.sub.3-C.sub.6alkinyl, C(C.sub.1-C.sub.4alkyl)=NOC.sub.1-C.sub.4alkyl, C.sub.1-C.sub.6haloalkyl, C.sub.1-C.sub.6haloalkoxy, C.sub.2-C.sub.6haloalkenyl, or C.sub.2-C.sub.6haloalkenyloxy; R.sub.3 is hydrogen, halogen, C.sub.1-C.sub.6alkyl; R.sub.4, R.sub.5 and R.sub.6, independently from each other, are hydrogen, halogen or --R.sub.7; with the proviso that at least one of R.sub.4, R.sub.5 and R.sub.6 is different from hydrogen; R.sub.7 is hydrogen, C.sub.1-C.sub.6alkyl, C.sub.1-C.sub.6haloalkyl or C.sub.1-C.sub.4alkoxyalkyl; and R.sub.8 is hydrogen or methoxy; and agrochemically acceptable salts/isomers/structural isomers/stereoisomers/diastereoisomers/enantiomers/tautomers and N-oxides of those compounds; and component (B) is a compound selected from compounds known for their fungicidal and/or insecticidal activity, is particularly effective in controlling or preventing fungal diseases of useful plants.

Claims

1. A fungicidal composition, comprising: (A) 3-(difluoromethyl)-N-methoxy-1-methyl-N-[1-methyl-2-(2,4,6-trichlorophenyl)ethyl]-1H-pyrazole-4-carboxamide and (B) fludioxonil, wherein the weight ratio of (A) to (B) is 1:4 to 4:1.

2. A method of controlling phytopathogenic fungi on useful plants or on propagation material thereof, which comprises applying to the useful plants, the locus thereof or propagation material thereof an effective amount of the composition of claim 1.

3. The composition of claim 1, wherein the weight ratio of (A) to (B) is 1:2 to 2:1.

4. The method of claim 2, wherein the phytopathogenic fungi is Alternaria spp.

5. The method of claim 2, wherein the phytopathogenic fungi is Botrytis cinerea.

6. The method of claim 2, wherein the phytopathogenic fungi is Fusarium culmorum.

7. The method of claim 2, wherein the phytopathogenic fungi is Microdochium nivale.

8. The method of claim 2, wherein the phytopathogenic fungi is Septoria tritici.

9. The method of claim 2, wherein the phytopathogenic fungi is Rhizoctonia solani.

10. A fungicidal composition, comprising: (A) 3-(difluoromethyl)-N-methoxy-1-methyl-N-[1-methyl-2-(2,4,6-trichlorophenyl)ethyl]-1H-pyrazole-4-carboxamide and (B) fludioxonil, wherein the weight ratio of (A) to (B) is synergistic as calculated by the Colby formula.

11. A method of controlling phytopathogenic fungi on useful plants or on propagation material thereof, which comprises applying to the useful plants, the locus thereof or propagation material thereof an effective amount of the composition of claim 3.

12. The method of claim 11, wherein the phytopathogenic fungi is Alternaria spp.

13. The method of claim 11, wherein the phytopathogenic fungi is Botrytis cinerea.

14. The method of claim 11, wherein the phytopathogenic fungi is Fusarium culmorum.

15. The method of claim 11, wherein the phytopathogenic fungi is Microdochium nivale.

16. The method of claim 11, wherein the phytopathogenic fungi is Septoria tritici.

17. The method of claim 11, wherein the phytopathogenic fungi is Rhizoctonia solani.

Description

BIOLOGICAL EXAMPLES

(1) A synergistic effect exists whenever the action of an active ingredient combination is greater than the sum of the actions of the individual components.

(2) The action to be expected E for a given active ingredient combination obeys the so-called COLBY formula and can be calculated as follows (COLBY, S. R. Calculating synergistic and antagonistic responses of herbicide combination. Weeds, Vol. 15, pages 20-22; 1967): ppm=milligrams of active ingredient (=a.i.) per liter of spray mixture X=% action by active ingredient (A) using p ppm of active ingredient Y=% action by active ingredient (B) using q ppm of active ingredient.

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

(4) $E=X+Y-\frac{X.Math.Y}{100}$

(5) If the action actually observed (O) is greater than the expected action (E), then the action of the combination is super-additive, i.e. there is a synergistic effect. In mathematical terms the synergism factor SF corresponds to O/E. In the agricultural practice an SF of 1.2 indicates significant improvement over the purely complementary addition of activities (expected activity), while an SF of 0.9 in the practical application routine signals a loss of activity compared to the expected activity.

(6) Liquid Culture Tests in Well Plates:

(7) Mycelia fragments or conidia suspensions of a fungus, prepared either freshly from liquid cultures of the fungus or from cryogenic storage, were directly mixed into nutrient broth. DMSO solutions of the test compound (max. 10 mg/ml) was diluted with 0.025% Tween20 by factor 50 and 10 l of this solution was pipetted into a microtiter plate (96-well format). The nutrient broth containing the fungal spores/mycelia fragments was then added to give an end concentration of the tested compound. The test plates were incubated in the dark at 24 C. and 96% rh. The inhibition of fungal growth was determined visually after 2-7 days, depending on the pathosystem, and percent antifungal activity relative to the untreated check was calculated.

Example B1: Fungicidal Action Against Botryotinia fuckeliana (Botrytis cinerea)/Liquid Culture (Gray Mould)

(8) Conidia of the fungus from cryogenic storage were directly mixed into nutrient broth (Vogels broth). After placing a (DMSO) solution of the test compounds into a microtiter plate (96-well format), the nutrient broth containing the fungal spores was added. The test plates were incubated at 24 C. and the inhibition of growth was determined visually 3-4 days after application.

Example B2: Fungicidal Action Against Pythium ultimum/Liquid Culture (Seedling Damping Off)

(9) Mycelia fragments and oospores of a newly grown liquid culture of the fungus were directly mixed into nutrient broth (PDB potato dextrose broth). After placing a (DMSO) solution of the test compounds into a microtiter plate (96-well format), the nutrient broth containing the fungal mycelia/spore mixture was added. The test plates were incubated at 24 C. and the inhibition of growth was determined visually 2-3 days after application.

Example B3: Fungicidal Action Against Sclerotinia sclerotiorum/Liquid Culture (Cottony Rot)

(10) Mycelia fragments of a newly grown liquid culture of the fungus were directly mixed into nutrient broth (PDB potato dextrose broth). After placing a (DMSO) solution of the test compounds into a microtiter plate (96-well format) the nutrient broth containing the fungal material was added. The test plates were incubated at 24 C. and the inhibition of growth was determined visually 3-4 days after application.

Example 84: Fungicidal Action Against Mycosphaerella arachidis (Cercospora arachidicola)/Liquid Culture (Early Leaf Spot)

(11) Conidia of the fungus from cryogenic storage were directly mixed into nutrient broth (PDB potato dextrose broth). After placing a (DMSO) solution of the test compounds into a microtiter plate (96-well format), the nutrient broth containing the fungal spores was added. The test plates were incubated at 24 C. and the inhibition of growth was determined visually 4-5 days after application.

Example B5: Fungicidal Action Against Tapesia yallundae W-Type (Pseudocercosporella herpotrichoides)/Liquid Culture (Eyespot)

(12) Conidia of the fungus from cryogenic storage were directly mixed into nutrient broth (PDB potato dextrose broth). After placing a (DMSO) solution of the test compounds into a microtiter plate (96-well format), the nutrient broth containing the fungal spores was added. The test plates were incubated at 24 C. and the inhibition of growth was determined visually 3-4 days after application.

Example B6: Fungicidal Action Against Mycosphaerella graminicola (Septoria tritici)/Liquid Culture (Septoria Blotch)

(13) Conidia of the fungus from cryogenic storage were directly mixed into nutrient broth (PDB potato dextrose broth). After placing a (DMSO) solution of the test compounds into a microtiter plate (96-well format), the nutrient broth containing the fungal spores was added. The test plates were incubated at 24 C. and the inhibition of growth was determined visually 4-5 days after application.

Example B7: Fungicidal Action Against Fusarium culmorum/Liquid Culture (Head Blight)

(14) Conidia of the fungus from cryogenic storage were directly mixed into nutrient broth (PDB potato dextrose broth). After placing a (DMSO) solution of the test compounds into a microtiter plate (96-well format), the nutrient broth containing the fungal spores was added. The test plates were incubated at 24 C. and the inhibition of growth was determined visually 3-4 days after application.

Example B8 Fungicidal Action Against Thanatephorus cucumeris (Rhizoctonia solani)/Liquid Culture (Foot Rot, Damping-Off)

(15) Mycelia fragments of a newly grown liquid culture of the fungus were directly mixed into nutrient broth (PDB potato dextrose broth). After placing a (DMSO) solution of the test compounds into a microtiter plate (96-well format), the nutrient broth containing the fungal material was added. The test plates were incubated at 24 C. and the inhibition of growth was determined visually 3-4 days after application.

(16) Leaf Disk or Leaf Segment Tests in Well Plates:

(17) Leaf disks or leaf segments of various plant species were cut from plants grown in the greenhouse. The cut leaf disks or segments were placed in multiwell plates (24-well format) onto water agar. The leaf disks were sprayed with a test solution before (preventative) or after (curative) inoculation. Compounds to be tested were prepared as DMSO solutions (max. 10 mg/ml) which were diluted to the appropriate concentration with 0.025% Tween20 just before spraying. The inoculated leaf disks or segments were incubated under defined conditions (temperature, relative humidity, light, etc.) according to the respective test system. A single evaluation of disease level was carried out 3-9 days days after inoculation, depending on the pathosystem. Percent disease control relative to the untreated check leaf disks or segments was then calculated.

Example B9 Fungicidal Action Against Plasmopara viticola/Grape/Leaf Disc Preventative (Late Blight)

(18) Grape vine leaf disks were placed on water agar in multiwell plates (24-well format) and sprayed with the formulated test compound diluted in water. The leaf disks were inoculated with a spore suspension of the fungus 1 day after application. The inoculated leaf disks were incubated at 19 C. and 80% rh under a light regime of 12 h light/12 h darkness in a climate cabinet and the activity of a compound was assessed as percent disease control compared to untreated when an appropriate level of disease damage appears in untreated check leaf disks (6-8 days after application).