NZ537038A

NZ537038A - Fungicidal mixtures comprising dithianon and an imidazole derivative

Info

Publication number: NZ537038A
Application number: NZ537038A
Authority: NZ
Inventors: Eberhard Ammermann; Reinhard Stierl; Ulrich Schofl; Klaus Schelberger; Maria Scherer; Michael Hinningsen; Randall Even Gold
Original assignee: Basf Ag
Priority date: 2002-07-17
Filing date: 2003-06-30
Publication date: 2006-08-31
Also published as: AU2003249899A1; JP4431495B2; WO2004006676A1; JP2006504648A; ATE493029T1; EP1524903B1; ES2357507T3; BR0311809B1; DE50313369D1; AU2003249899B2; EP1524903A1; BR0311809A

Abstract

Fungicidal mixtures comprising a synergistically active quantity of (a) a dithianon compound of formula (I); and (b) an imidazole derivative compound of formula (II) is disclosed. Methods for controlling harmful fungi by using the mixtures of said compounds (I) and (II); and the use of the compounds for producing said mixtures are also disclosed.

Description

New Zealand Paient Spedficaiion for Paient Number 537038 53703.-; Fungicidal mixtures based on dithianon The present invention relates to fungicidal mixtures, comprising 5 A) the compound of the formula I and B) the imidazole derivative of the formula Ila in a synergistically effective amount.

Moreover, the invention relates to methods for controlling harmful fungi using mixtures of the compounds I and Ila, and to 20 the use of the compounds I and Ila for preparing such mixtures.

It is an object of the present invention to provide mixtures which have improved activity against harmful fungi combined with a reduced total amount of active compounds applied (synergistic 25 mixtures), with a view to reducing the application rates and improving the activity spectrum of the known compounds, or at least to provide a useful alternative.

We have found that this object is achieved by the mixtures 30 defined at the outset. Moreover, we have found that applying the compounds I and Ila simultaneously, i.e. together or separately, or applying the compounds I and Ila in succession provides better intellectual property office of im.z. - 3 NAY 2G06 nrr»r i\/cn 2 control of harmful fungi than is possible with the individual compounds alone.

The compound of the formula I (common name: dithianon) and processes for its preparation are described in GB-A 857 383.

The compound of the formula Ila (common name: cyazofamid) is known from EP-A 2 98 196.

When preparing the mixtures, it is preferred to employ the pure active compounds I and Ila, with which further active compounds against harmful fungi or other pests, such as insects, arachnids or nematodes, or else herbicidal or growth-regulating active compounds or fertilizers can be admixed as required.

The mixtures of the compounds I and Ila or the simultaneous joint or separate use of the compounds I and Ila have outstanding action against a wide range of phytopathogenic fungi, in particular from the classes of the Ascomycetes, Deuteromycetes, 20 Oomycetes and Basidiomycetes.

They are especially important for controlling a large number of fungi in a variety of crop plants, such as cotton, vegetable species (for example cucumbers, beans and cucurbits), coffee, 25 fruit species, soya, grapevine, ornamentals, and a variety of seeds.

They are particularly suitable for controlling the following phytopathogenic fungi: Erysiphe cichoracearum and Sphaerotheca 30 fuliginea in cucurbits, Podosphaera leucotricha in apples, Uncinula necator in grapevines, Ustilago species in cereals and sugarcane, Venturia inaequalis (scab) in apples, Botrytis cinerea (gray mold) in strawberries, vegetables, ornamentals and grapevines, Cercospora arachidicola in groundnuts, Phytophthora 35 infestans in potatoes and tomatoes, Pseudoperonospora species in cucurbits and hops, Plasmopara viticola in grapevines, Alternaria species in vegetables and fruit and Fusarium and Verticillium species. 40 The compounds I and Ila can be applied simultaneously, that is either together or separately, or in succession, the sequence, in intellectual property office of n.z. - 3 MAY 2006 Rpr.pivpn 3 the case of separate application, generally not having any effect on the control results.

The compounds I and Ila are usually applied in a weight ratio of 5 from 100:1 to 1:10, preferably from 10:1 to 1:1, in particular from 5:1 to 1:1.

The application rates of the compounds I are generally from 5 to 2 000 g/ha, preferably from 10 to 1 000 g/ha, in particular from 10 50 to 750 g/ha, and those of the compound Ila are generally from 5 g/ha to 500 g/ha, preferably from 50 to 500 g/ha, in particular from 50 to 200 g/ha.

For seed treatment, the application rates of the mixture are 15 generally from 0.001 to 1 g/kg of seed, preferably from 0.01 to 0.5 g/kg, in particular from 0.01 to 0.1 g/kg.

If phytopathogenic harmful fungi are to be controlled, the separate or joint application of the compounds I and Ila or of 20 the mixtures of the compounds I and Ila is effected by spraying or dusting the seeds, the plants or the soils before or after sowing, or before or after plant emergence.

The following are examples of formulations: 1. Products for dilution with water A) Water-soluble concentrates (SL) 10 parts by weight of the active compounds are dissolved in water or in a water-soluble solvent. As an alternative, wetters or other auxiliaries are added. The active compound dissolves upon dilution with water.

B) Dispersible concentrates (DC) parts by weight of the active compounds are dissolved in cyclohexanone with addition of a dispersant, for example polyvinylpyrrolidone. Dilution with water gives a dispersion. 40 intellectual, property office of N.Z - 3 MAY 2006 RFCFIVFD 4 C) Emulsifiable concentrates (EC) parts by weight of the active compounds are dissolved in xylene with addition of calcium dodecylbenzenesulfonate and 5 castor oil ethoxylate (in each case 5% strength). Dilution with water gives an emulsion.

D) Emulsions (EW, EO) 40 parts by weight of the active compounds are dissolved in xylene with addition of calcium dodecylbenzenesulfonate and castor oil ethoxylate (in each case 5% strength). This mixture is introduced into water by means of an emulsifier machine (Ultraturrax) and made into a homogeneous emulsion. Dilution with intellectual property office of im.2. - 3 MAY 2006 ncorsurn PF 53741 E) Suspensions (SC, OD) In an agitated ball mill, 20 parts by weight of the active compounds are comminuted with addition of dispersants, wetters 5 and water or an organic solvent to give a fine active compound suspension. Dilution with water gives a stable suspension of the active compound.

F) Water-dispersible granules and water-soluble granules (WG, 10 SG) 50 parts by weight of the active compounds are ground finely with addition of dispersants and wetters and made as water-dispersible or water-soluble granules by means of technical appliances (for 15 example extrusion, spray tower, fluidized bed). Dilution with water gives a stable dispersion or solution of the active compound.

G) Water-dispersible powders and water-soluble powders (WP, SP) 75 parts by weight of the active compounds are ground in a rotor-stator mill with addition of dispersants, wetters and silica gel. Dilution with water gives a stable dispersion or solution of the active compound. 2. Products to be applied undiluted H) Dustable powders (DP) 5 parts by weight of the active compounds are ground finely and mixed intimately with 95% of finely divided kaolin. This gives a dustable product.

X) Granules (GR, FG, GG, MG) 0.5 part by weight of the active compounds is ground finely and associated with 95.5% carriers. Current methods are extrusion, spray-drying or the fluidized bed. This gives granules to be applied undiluted. 40 J) ULV solutions (UL) parts by weight of the active compounds are dissolved in an organic solvent, for example xylene. This gives a product to be 45 applied undiluted.

PF 53741 6 The active compounds can be used as such, in the form of their formulations or the use forms prepared therefrom, for example in the form of directly sprayable solutions, powders, suspensions or dispersions, emulsions, oil dispersions, pastes, dustable 5 products, materials for spreading, or granules, by means of spraying, atomizing, dusting, spreading or pouring. The use forms depend entirely on the intended purposes; they are intended to ensure in each case the finest possible distribution of the active compounds according to the invention.

Aqueous use forms can be prepared from emulsion concentrates, pastes or wettable powders (sprayable powders, oil dispersions) by adding water. To prepare emulsions, pastes or oil dispersions, the substances, as such or dissolved in an oil or solvent, can be homogenized in water by means of a wetter, tackifier, dispersant or emulsifier. However, it is also possible to prepare concentrates composed of active substance, wetter, tackifier, dispersant or emulsifier and, if appropriate, solvent or oil, and such concentrates are suitable for dilution with water.

The active compound concentrations in the ready-to-use preparations can be varied within relatively wide ranges. In general, they are from 0.0001 to 10%, preferably from 0.01 to 1%.

The active compounds may also be used successfully in the ultra-low-volume process (ULV), it being possible to apply formulations comprising over 95% by weight of active compound, or even to apply the active compound without additives.

Oils of various types, wetters, adjuvants, herbicides, fungicides, other pesticides, or bactericides may be added to the active compounds, even, if appropriate, not until immediately prior to use (tank mix). These agents can be admixed with the compositions according to the invention in a weight ratio from 1:10 to 10:1.

The fungicidal action of the compounds and of the mixtures can be demonstrated by the following experiments: 40 The active compounds, separately or jointly, were prepared as a stock solution comprising 0.25% by weight of active compound in acetone or DMSO. 1% by weight of the emulsifier Uniperol® EL (wetting agent having emulsifying and dispersant action based on ethoxylated alkylphenols) was added to this solution, and the 45 mixture was diluted with water to the desired concentration.

PF 53741 7 Use example 1 - activity against late blight on tomatoes caused by Phytophthora infestans Leaves of potted plants of the tomato cultivar "Large Fruited St. 5 Pierre" were sprayed to runoff point with an aqueous suspension having the concentration of active compounds stated below. The next day, the leaves were infected with a cold aqueous zoospore suspension of Phytophthora infestans having a density of 0.25 x 106 spores/ml. The plants were then placed in a 10 water-vapor-saturated chamber at 18 - 20°C. After 6 days, the blight on the untreated but infected control plants had developed to such an extent that the infection could be determined visually in %.

Evaluation is carried out by determining the infected leaf areas in percent. These percentages are converted into efficacies.

The efficacy (E) is calculated as follows using Abbot's formula: E = (1 - a/P)*100 a corresponds to the fungal infection of the treated plants in % and P corresponds to the fungal infection of the untreated (control) plants in % An efficacy of 0 means that the infection level of the treated plants corresponds to that of the untreated control plants; an 30 efficacy of 100 means that the treated plants were not infected.

The expected efficacies of the active compound mixtures are determined using Colby's formula [R.S. Colby, Weeds 15., 20—22 (1967)] and compared with the observed efficacies.

Colby's formula: E = x + y + z — x«yz/100 40 E expected efficacy, expressed in % of the untreated control, when using the mixture of the active compounds A, B and C at the concentrations a, b and c x efficacy, expressed in % of the untreated control, when using 45 active compound A at a concentration of a 8 y efficacy, expressed in % of the untreated control, when using active compound B at a concentration of b z efficacy, expressed in % of the untreated control, when using 5 active compound C at a concentration of c Table A - Individual active compounds Example Active compound Concentration of Efficacy in % of active compound the untreated in the spray control liquor [ppm] 1 Control (90% infection) 0 (untreated) 2 I (dithianon) 0 7 . 5 0 3.73 0 3 Ila 6 89 (cyazofamid) 3 78 1.5 67 0.75 56 0.375 44 Table B - Combinations according to the invention Example Active compound mixture Concentration Mixing ratio Observed efficacy Calculated efficacy*) 4 I + Ila 15 + 1.5 ppm 10 : 1 99 67 I + Ila 7.5 + 0.75 ppm 10 : 1 83 56 6 I + Ila 3.75 + 0.375 ppm 10 : 1 67 44 7 I + Ila 3.75 + 3 ppm 1.25 : 1 100 78 8 I + Ila 3.75 + 6 ppm 1 : 1.6 100 89 *) efficacy calculated using Colby's formula intellectual property office of n.z. - 3 MAY 2006 RECEIVED 9 Use example 2: Activity against peronospora of grape vines caused by Plasmopara viticola Leaves of potted grape vines of the cultivar "Miiller-Thurgau" 5 were sprayed to runoff point with an aqueous suspension having the concentration of active compounds stated below. To be able to assess the persistency of the substances, the plants were, after the spray coating had dried on, placed in a greenhouse for 3 days. Only then were the leaves inoculated with an aqueous 10 zoospore suspension of Plasmopara viticola. The grape vines were then initially placed in a water-vapor-saturated chamber at 24°C for 48 hours and then in a greenhouse at temperatures between 20 and 30°C for 5 days. After this period of time, the plants were, to promote sporangiophore eruption, again placed in a moist 15 chamber for 16 hours. The extent of the development of the infection on the undersides of the leaves was then determined visually.

Table C - Individual active compounds Example Active compound Concentration of Efficacy in % of active compound the untreated in the spray control liquor [ppm] 9 Control (96% infection) 0 (untreated) I (dithianon) 7.5 58 3.73 48 11 Ila 6 16 (cyazofamid) 3 16 0.75 16 0. 375 6 Table D - Combinations according to the invention Example Active compound mixture Concentration Mixing ratio Observed efficacy Calculated efficacy*) 12 I + Ila 7.5 + 0.75 ppm 10 : 1 79 65 13 I + Ila 3.75 + 0.375 ppm 10 : 1 69 51 14 I + Ila 3.75 + 3 ppm 1.25 : 1 69 56 ' ,wtellect(jal property office i of n.2. - 3 MAY 'i

Claims

10 15 I + Ila 74 56 3.75 + 6 ppm 1:1.6 *) efficacy calculated using Colby's formula The test results show that, for all mixing ratios, the observed efficacy is higher than that predicted using Colby's formula. intellectual PROPERTY office of N.i - 3 NAY 2005 5 10 15 20 25 30 35 40 45 PF 53741 11 We claim:

1. A fungicidal mixture, comprising A) the compound of the formula I 0 CN I CN and B) the imidazole derivative of the formula Ila ci N Ila in a synergistically effective amount.

2. A fungicidal mixture as claimed in claim 1, wherein the weight ratio of the compound I to the compound Ila is from 100:1 to 1:10.

3. A fungicidal composition comprising a solid or liquid carrier and a mixture as claimed in claim 1.

4. A method for controlling harmful fungi, which comprises treating the harmful fungi, their habitat, or the plants, seeds, soils, areas, materials or spaces to be kept free from them with the compound of the formula I, the imidazole derivative of the formula Ila as set forth in claim 1.

5. A method as claimed in claim 4, which comprises treating the harmful fungi, their habitat, or the plants, seeds, soils, areas, materials or spaces to be kept free from them with from 5 to 2000 g/ha of the compound I as set forth in claim 1.

6. A method as claimed in claim 4, which comprises treating the harmful fungi, their habitat, or the plants, seeds, soils, areas, materials or spaces to be kept free from them with from 5 to 500 g/ha of the compound Ila as set forth in claim 1. AMENDED SHEET 12

7. A fungicidal mixture as claimed in claim 1 substantially as herein described with reference to any example thereof.

8. A fungicidal mixture as claimed in claim 1 substantially as 5 herein described with reference to any one of Examples 4 to E of Table B or any one of Examples 12 to 15 of Table D.

9. A fungicidal composition as claimed in claim 3 substantially as herein described with reference to any example thereof. 10

10. A method as claimed in claim 4 substantially as herein described with reference to any example thereof. INTELLECTUAL PROPERTY OFFICE OF N.Z. - 3 MAY 2006 a"™ f" iv/ Ezr n