ZA200600787B - Fungicidal mixtures for combating rice pathogens - Google Patents

Description

Lo PF 54654 . . ;

Fungicidal mixtures for combating rice pathogens

The present invention relates to fungicidal mixtures for controlling rice pathogens, comprising as active components 1) the triazolopyrimidine derivative of the formula I,

CH, 0) F F

J

N~

NT

¢ = = F

Ey Cl and 2) an acryloylmorpholide of the formula Il,

X

OO, cH—4

N I coy 0]

CH,O in which X is chlorine or fluorine in a synergistically eftective amount.

Moreover, the invention relates to a method for controlling rice pathogens using mix- tures of the compound | with the compounds Il and to the use of the compound | with the compounds lI for preparing such mixtures and compositions comprising these mix- tures.

The compound |, 5-chloro-7-(4-methylpiperidin-1-yl)-6-(2,4,6-trifluorophenyl)-[1,2,4]tri- azolo[1,5-a]pyrimidine, its preparation and its action against harmful fungi are known from the literature (WO 98/46607).

The compounds ll, their preparation and their action against harmful fungi are likewise known from the literature (EP-A 120 321). The compound ll in which X is chlorine, 3-(4- chlorophenyl)-3-(3,4-dimethoxyphenyl)-1-morpholin-4-yipropenone (lla), is, under the common name “dimethomorph”, a long-established fungicide used against Oomycetes

Co PF 54654 in the cultivation of potatoes and vegetables. The compound Il in which X is fluorine, 3- (4-fluorophenyl)-3-(3,4-dimethoxyphenyl)-1-morpholin-4-ylpropenone (lib), is, under the

E common name flumorph, likewise known (EP-A 860 438). Compounds lla and IIb are present as E,Z isomer mixtures.

Cl F

OZ OI cH—4 la cH—4 lib

N N

CH,0 Q ) CY CH;0 ) CY 0 0)

CH,O CH,O

Mixtures of triazolopyrimidine derivatives with dimethomorph are known in a general manner from EP-A 988 790. The compound | is embraced by the general disclosure of this publication, but not explicitly mentioned. Accordingly, the combination of compound with the compounds Il is novel.

The synergistic mixtures known from EP-A 988 790 are described as being fungicidally active against various diseases of cereal, fruit and vegetable, in particular mildew on wheat and barley or gray mold on apples.

Owing to the special cultivation conditions of rice plants, the requirements that a rice fungicide has to meet are considerably different than those that fungicides used in ce- real or fruit growing have to meet. There are significant differences in the application method: in rice crops, the fungicide is usually applied directly onto the soil during or shortly after sowing. The fungicide is taken up into the plant via the roots and trans- ported in the sap of the plant to the plant parts to be protected. For rice fungicides, high systemic action is therefore essential. In contrast, in cereal or fruit growing, the fungi- cide is usually applied onto the leaves or the fruits; accordingly, in these crops the sys- temic action of the active compounds is considerably less important.

Moreover, rice pathogens are typically different from those in cereal or fruit. Pyricularia oryzae and Corticium sasakii (syn. Rhizoctonia solani) are the pathogens of the dis- eases most prevalent in rice plants. Rhizoctonia solani is the only pathogen of agricul- tural significance from the sub-class Agaricomycetidae. In contrast to most other fungi, this fungus attacks the plants not via spores but via a mycelium infection.

For these reasons, findings concerning the fungicidal activity of active compounds in the cultivation of cereals or fruit cannot be transferred to rice crops.

Ld ]

Co "PF 54654

A need exists to provide, with a view to an effective control of rice pathogens at appli- cation rates which are as low as possible, mixtures which, at a reduced total amount of active compounds, have improved action against the harmful fungi.

We have found that this need is fulfilled by the mixtures defined at the outset. Surpris- ingly, it has been found that the mixtures defined at the outset allow considerably better control of rice pathogens than the dimethomorph mixtures disclosed in EP-A 988 790.

Moreover, we have found that simultaneous, that is joint or separate, application of the compounds | and the compounds !l or successive application of the compounds | and the compounds Il allows better control of rice pathogens than is possibie with the indi- vidual compounds.

When preparing the mixtures, it is preferred to employ the pure active compounds | and lla or IIb, to which further active compounds against harmful fungi or other pests, such as insects, arachnids or nematodes, or else herbicidal or growth-regulating active com- pounds or fertilizers can be added.

Further suitable active compounds in the above sense are, in particular, fungicides selected from the following group: e acylalanines, such as benalaxyl, metalaxyl, ofurace or oxadixyl, e amine derivatives, such as aldimorph, dodine, dodemorph, fenpropimorph, fenpropidin, guazatine, iminoctadine, spiroxamine or tridemorph, « anilinopyrimidines, such as pyrimethanil, mepanipyrim or cyprodinyl, eo antibiotics, such as cycloheximide, griseofulvin, kasugamycin, natamycin, polyoxin or streptomycin, e azoles, such as bitertanol, bromoconazole, cyproconazole, difenoconazole, dinitroconazole, epoxiconazole, fenbuconazole, fluquiconazole, flusilazole, flutriafol, hexaconazole, imazalil, ipconazole, metconazole, myclobutanil, penconazole, propiconazole, prochloraz, prothioconazole, simeconazole, tebuconazole, tetraconazole, triadimefon, triadimenol, triflumizole or triticonazole, e dicarboximides, such as iprodione, myclozolin, procymidone or vinclozolin, ¢ dithiocarbamates, such as ferbam, nabam, maneb, mancozeb, metam, metiram, propineb, polycarbamate, thiram, ziram or zineb, e heterocyclic compounds, such as anilazine, benomyl, boscalid, carbendazim, car- boxin, oxycarboxin, cyazofamid, dazomet, dithianon, famoxadone, fenamidone, fenarimol, fuberidazole, flutotanil, furametpyr, isoprothiolane, KIF 230, mepronil, nuarimol, picobenzamid, probenazole, proquinazid, pyrifenox, pyroquilon, quinoxy-

AMENDED SHEET

Co PF 54654 fen, silthiofam, thiabendazole, thifluzamide, thiophanate-methyl, tiadinil, tricyciazole or triforine, e copper fungicides, such as Bordeaux mixture, copper oxychloride, copper hydrox- ide, copper oxide, (basic) copper sulfate, copper oxychloride sulfate, e nitrophenyl derivatives, such as binapacryl, dinocap, dinobuton or nitrophthal- isopropyl, : o phenylpyrroles, such as fenpiclonil or fludioxonil, e sulfur, e other fungicides, such as acibenzolar-S-methyl, benthiavaiicarb, carpropamid, chlorothalonil, cyflufenamid, cymoxanil, dazomet, diclomezine, diclocymet, diethofencarb, edifenphos, ethaboxam, fenhexamid, fentin acetate, fenoxanil, ferimzone, fluazinam, fosetyl, fosetyl-aluminum, iprovalicarb, hexachlorobenzene, metrafenone, pencycuron, propamocarb, phthalide, tolclofos-methyl, quintozene or zoxamide, eo strobilurins, such as azoxystrobin, dimoxystrobin, fluoxastrobin, kresoxim-methyl, metominostrobin, orysastrobin, picoxystrobin, pyraclostrobin or trifloxystrobin, + sulfenic acid derivatives, such as captafol, captan, dichlofluanid, folpet or tolylflua- nid, « cinnamides and analogous compounds, such as flumetover.

In one embodiment of the mixtures according to the invention, the compounds | and I are admixed with a further fungicide [ll or two fungicides Ill and IV.

Suitable components Ill and, if appropriate, IV from this list are in particular the stro- bilurins, dithiocarbamates, copper fungicides and the other fungicides mentioned.

Preference is given to mixtures of the compounds | and Il with one component lI.

Particular preference is given to mixtures of the compounds | and |i.

Especially preferred are mixtures of the compound | with dimethomorph (lla).

The mixtures of compounds | and lla or lib, or the compounds | and lla or IIb used si- multaneously, that is jointly or separately, exhibit outstanding action against rice patho- gens from the classes of the Ascomycetes, Deuteromycetes and Basidiomycetes. They have high systemic action and can therefore be used for the treatment of seed and as foliar- and soil-acting fungicides.

BEE PF 54654

They are especially important for controlling harmful fungi on rice plants and their seeds, such as Bipolaris and Drechslera species, and also Pyricularia oryzae. They are particularly suitable for controlling rice blast caused by Pyricularia oryzae. 5S In addition, the combination according to the invention of the compounds | and Il is also suitable for controlling other pathogens, such as, for example, Septoria and Puccinia species in cereals and Alternaria and Boytritis species in vegetables, fruit and grape- vine.

The compounds | and the compounds lia or lib can be applied simultaneously, that is jointly or separately, or in succession, the sequence, in the case of separate applica- tion, generally not having any effect on the result of the control measures.

The compound | and the compounds Il are usually applied in a weight ratio of from 100:1 to 1:100, preferably from 20:1 to 1:20, in particular from 10:1 to 1:10.

The components ll and, if appropriate, IV are, if desired, mixed with the compound | in a ratio of from 20:1 to 1:20.

Depending on the desired effect, the application rates of the mixtures according to the invention are from 5 g/ha to 1500 g/ha, preferably from 50 to 1000 g/ha, in particular : from 50 to 750 g/ha.

Correspondingly, the application rates of the compound | are generally from 1 to 1000 g/ha, preferably from 10 to 750 g/ha, in particular from 20 to 500 g/ha.

Correspondingly, the application rates of the compound Il are generally from 1 to 1000 g/ha, preferably from 10 to 750 g/ha, in particular from 20 to 500 g/ha.

Inthe treatment of seed, the application rates of the mixture are generally from 1 to 1000 g/100 kg of seed, preferably from 1 to 200 g/100 kg, in particular from 5 to 100 g/100 kg.

In the control of harmful fungi which are pathogenic to rice plants, the separate or joint application of the compounds | and Il or of the mixtures of the compounds | and Il is carried out by spraying or dusting the seeds, the seedlings, the plants or the soils be- fore or after sowing of the plants or before or after emergence of the plants. The com- pounds are preferably applied jointly or separately, preferably by applying granules or by dusting the soils.

- PF 54654

The mixtures according to the invention or the compounds | and 11 can be converted into the customary formulations, for example solutions, emulsions, suspensions, dusts, powders, pastes and granules. The application form depends on the particular pur- pose; in each case, it should ensure a fine and uniform distribution of the compound according to the invention.

The formulations are prepared in a known manner, for example by extending the active compound with solvents and/or carriers, if desired using emulsifiers and dispersants.

Solvents/auxiliaries which are suitable are essentially: - water, aromatic solvents (for example Solvesso products, xylene), paraffins (for example mineral ail fractions), alcohols (for example methanol, butanol, pen- tanol, benzyl! alcohol), ketones (for example cyclohexanone, gamma- butyrolactone), pyrrolidones (NMP, NOP), acetates (glycol diacetate), glycols, fatty acid dimethylamides, fatty acids and fatty acid esters. In principle, solvent mixtures may also be used. - carriers such as ground natural minerals (for example kaolins, clays, talc, chalk) and ground synthetic minerals (for example highly disperse silica, silicates); emulsifiers such as nonionic and anionic emulsifiers (for example polyoxyethyl- ene fatty alcohol ethers, alkylsulfonates and arylsulfonates) and dispersants such as lignin-sulfite waste liquors and methylcellulose.

Suitable surfactants are alkali metal, alkaline earth metal and ammonium salts of ligno- sulfonic acid, naphthalenesulfonic acid, phenolsuifonic acid, dibutylnaphthalenesulfonic acid, alkylarylsulfonates, alkyl sulfates, alkylsulfonates, fatty alcohol sulfates, fatty acids and sulfated fatty alcohol glycol ethers, furthermore condensates of sulfonated naph- thalene and naphthalene derivatives with formaldehyde, condensates of naphthalene or of naphthalenesulfonic acid with phenol and formaldehyde, polyoxyethylene octyl- phenyl ether, ethoxylated isooctylphenol, octylphenol, nonylphenal, alkylphenyl poly- glycol ethers, tributylphenyl polyglycol ether, tristearylphenyl polyglycol ether, alkylaryl polyether alcohols, alcohol and fatty alcohol/ethylene oxide condensates, ethoxylated castor oil, polyoxyethylene alkyl ethers, ethoxylated polyoxypropylene, lauryl alcohol polyglycol ether acetal, sorbitol esters, lignin-sulfite waste liquors and methylcellulose.

Substances which are suitable for the preparation of directly sprayable solutions, emul- sions, pastes or oil dispersions are mineral oil fractions of medium to high boiling point, such as kerosene or diesel oil, furthermore coal tar oils and oils of vegetable or anima] origin, aliphatic, cyclic and aromatic hydrocarbons, for example toluene, xylene, paraf- fin, tetrahydronaphthalene, alkylated naphthalenes or their derivatives, methanol, etha-

Co PF 54654 7 720068700737 nol, propanol, butanol, cyclohexanol, cyclohexanone, isophorone, strongly polar sol- vents, for example dimethyl sulfoxide, N-methylpyrrolidone and water.

Powders, materials for spreading and dustable products can be prepared by mixing or concomitantly grinding the active substances with a solid carrier. : Granules, for example coated granules, impregnated granules and homogeneous granules, can be prepared by binding the active compounds to solid carriers. Examples of solid carriers are mineral earths such as silica gels, silicates, talc, kaolin, attaclay, limestone, lime, chalk, bole, loess, clay, dolomite, diatomaceous earth, calcium sulfate, magnesium sulfate, magnesium oxide, ground synthetic materials, fertilizers, such as, for example, ammonium sulfate, ammonium phosphate, ammonium nitrate, ureas, and products of vegetable origin, such as cereal meal, tree bark meal, wood meal and nut- shell meal, cellulose powders and other solid carriers.

In general, the formulations comprise from 0.01 to 95% by weight, preferably from 0.1 to 90% by weight, of the active compounds. The active compounds are employed in a purity of from 90% to 100%, preferably 95% to 100% (according to NMR spectrum).

The following are examples of formulations: 1. Products for dilution with water

A) 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) 20 parts by weight of the active compounds are dissolved in cyclohexanone with addi- tion of a dispersant, for example polyvinylpyrrolidone. Dilution with water gives a dis- persion.

C) Emulisifiable concentrates (EC) 15 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).

Dilution with water gives an emulsion.

BER PF 54654

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 (Ultraturax) and made into a homogeneous emulsion. Dilution with water gives an emulsion.

E) Suspensions (SC, OD)

In an agitated ball mill, 20 parts by weight of the active compounds are comminuted with addition of dispersants, wetters and water or an organic solvent to give a fine ac- tive compound suspension. Dilution with water gives a stable suspension of the active compound.

F) Water-dispersible granules and water-soluble granules (WG, SG) 50 parts by weight of the active compounds are ground finely with addition of dispers- ants and wetters and made into water-dispersible or water-soluble granules by means of technical appliances (for 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 addi- tion of dispersants, wetters and silica gel. Dilution with water gives a stable dispersion or solution of the active compound. 2. Products to be applied neat

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.

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 neat.

J ULV solutions (UL) 10 parts by weight of the active compounds are dissolved in an organic solvent, for example xylene. This gives a product to be applied neat.

The active compounds can be used as such, in the form of their formulations or the use 40 forms prepared therefrom, for example in the form of directly sprayable solutions, pow-

I PF 54654 ders, suspensions or dispersions, emulsions, oil dispersions, pastes, dustable prod- ucts, materials for spreading, or granules, by means of spraying, atomizing, dusting, spreading or pouring. The use forms depend entirely on the intended purposes; it is intended to ensure in each case the finest possible distribution of the active com- pounds 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. Al- ternatively, it is possible to prepare concentrates composed of active substance, wet- ter, tackifier, dispersant or emulsifier and, if appropriate, solvent or oil, and such con- centrates 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 0.01t0 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.

Various types of oils, wetters, adjuvants, herbicides, fungicides, other pesticides, or bactericides may be added to the active compounds, if appropriate just immediately prior to use (tank mix). These agents can be admixed to the agents according to the invention, usually done in a weight ratio from 1:10 to 10:1.

The compounds | and Il or the mixtures or the corresponding formulations are applied by treating the harmful fungi or the plants, seeds, soils, areas, materials or spaces to be kept free from them with a fungicidally effective amount of the mixture or, in the case of separate application, of the compounds 1 and II. Application can be carried out before or after infection by the harmful fungi.

The fungicidal action of the compound and the mixtures can be demonstrated by the experiments below:

The active compounds, separately or jointly, were prepared as a stock solution with 0.25% by weight of active compound in acetone or DMSO. 1% by weight of the emulsi-

oe PF 54654 fier Uniperol® EL (wetting agent having emulsifying and dispersing action based on ethoxylated alkylphenols) was added to this solution, and the solution was diluted with water to the desired concentration.

Use example — protective activity against rice blast caused by Pyricularia oryzae

Leaves of rice seedlings of the cultivar "Tai-Nong 67", which had been grown in pots, : were sprayed to runoff point with an aqueous suspension having the concentration of ac- tive compounds stated below. The next day, the plants were inoculated with an aqueous spore suspension of Pyricularia oryzae. The test plants were then placed in climatized chambers at 22-24°C and 95-99% relative atmospheric humidity for 6 days. The extent of the development of the infection on the leaves was then determined visually.

Evaluation was carried out by determining the infected leaf areas in percent. These per- centages were converted into efficacies.

The efficacy (E) is calculated as follows using Abbot's formuia:

E=(1-a/B) 100 o corresponds to the fungicidal infection of the treated plants in % and

B corresponds to the fungicidal 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 efficacy of 100 means that the treated plants were not infected.

The expected efficacies of the mixtures of active compounds 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-xy/100

E expected efficacy, expressed in % of the untreated control, when using the mix- ture of the active compounds A and B at the concentrations a and b

X efficacy, expressed in % of the untreated control, when using active compound A 40 at the concentration a

BE PF 54654 y efficacy, expressed in % of the untreated control, when using active compound B at the concentration b

The comparative compounds used were compounds A and B, known from the di- methomorph mixtures described in EP-A 988 790:

CH,

CF,

AF F

F H,C™ "NH

N A B

Nn CN > “N — F /4 2 ¢ _ NTN" cl

NEN a ©

Table A - Individual active compounds

Concentrati f active ) centra on or act Efficacy in % of the un-

Example Active compound compound in the spray i treated control liquor [ppm] control (untreated) Co - (90% infection)

EEE I EE I RE I

3 lla (dimethomorph) 4

P 0.25 4 {Ib (flumorph) 4

P 0.25

Comparative compound 1 11

A

Cc i d

Ei

B

Table B — Mixtures according to the invention

Mixture of active compounds;

Example i. P Observed efficacy | Calculated efficacy*) concentration; mixing ratio oo I+ lla 7 1+4 ppm 78 11 1:4

To PF 54654 concentration; mixing ratio 1+ lla 1 + 0.25 ppm 56 11

I +1ib 1 +4 ppm i +1ib 10 1+ 0.25 ppm 44 1 2] le [oe *) efficacy calculated using Colby’s formula

Table C — Comparative experiments — mixtures known from EP-A 988 780

Ea pid] El concentration; mixing ratio

A+ lla 11 1+ 4 ppm 11 1.4

A+lla 12 1+ 0.25 ppm 11 11

ERE oo B+lla 13 1+4 ppm 33 1:4

B+ lla 14 1+ 0.25 ppm 22 22 4:1 *) efficacy calculated using Colby’s formula

The test results show that the mixtures according to the invention have, owing to strong synergism, considerably better activity against rice biast than the dimethomorph mix- tures known from EP-A 988 780, although the comparative compounds as individual active compounds have an activity better than or comparable to that of compound I. “Comprises/comprising” when used in this specification is taken to specify the pres- ence of stated features, integers, steps or components but does not preclude the pres- ence or addition of one or more other features, integers, steps or components or groups thereof.

AMENDED SHEET

Claims (16)

~~ yr : PF 54654 We claim:

1. A fungicidal mixture for-centrolling-rice-pathogens, comprising 1) the triazolopyrimidine derivative of the formula, CH, CO F N l 29 NN a and 2) an acryloyimorpholide of the formula I, X 2 ch—4 N I wo (0) CH,O in which X is chlorine or fluorine, in a synergistically effective amount.

2. A fungicidal mixture comprising the compound of the formula | and the com- pounds of the formula Il in a weight ratio of from 100:1 to 1:100.

3. A fungicidal mixture comprising, as acryloylmorpholide, dimethomorph of the for- mula lla Cl 2, ch—4 1a N ono) 0 Cc HO AMENDED SHEET

- -,

: .PF 54654

4. A fungicidal composition comprising a liquid or solid carrier and a mixture as claimed in any one of claims 1 to 3.

5. A method for controlling harmfut fungi which are rice pathogens, which comprises treating the fungi, their habitat or the plants, the soil or the seeds to be protected against fungal attack with an effective amount of the compound | and one of the compounds ll as set forth in claim 1.

6. A method as claimed in claim 5, wherein the compounds | and I! as set forth in claim 1 are applied simultaneously, that is jointly or separately, or in succession.

7. A method as claimed in claim 5, wherein the mixture as claimed in any of claims 1 to 3 is applied in an amount of from 5 g/ha to 1500 g/ha.

8. A method as claimed in claim 5 or 6, wherein the mixture as claimed in any of claims 1 to 3 is applied in an amount of from 1 to 1000 g/100 kg of seed.

9. A method as claimed in any one of claims 5 to 8, wherein the harmful fungus Pyricularia oryzae is controlled.

10. Seed, comprising the mixture as claimed in claim 1 or 2 in an amount of from 1 to 1000 g/100 kg.

11. The use of the compound | and the compound || as set forth in claim 1 for prepar- ing a composition suitable-for-centrolling-harmful-fungi as claimed in claim 4.

12. A fungicidal mixture as claimed in any one of claims 1 to 3, substantially as here- inbefore described or exemplified.

13. A fungicidal mixture including any new and the inventive integer or combination : of integers, substantially as herein described.

14. A fungicidal composition as claimed in claim 4, substantially as hereinbefore de- scribed or exemplified.

15. A fungicidal composition including any new and the inventive integer or combina- tion of integers, substantially as herein described.

16. A method according to the invention for controlling harmful fungi, substantially as 40 hereinbefore described or exemplified. AMENDED SHEET