1,2,4-Triazole derivatives

Abstract

1,2,4-Triazole derivatives of the formula ##STR1## in which R.sub.1 denotes methyl or optionally substituted phenyl,R.sub.2 denotes R.sub.3 O-- in which R.sub.3 is optionally substituted alkyl, alkinyl preferably having up to 3 carbon atoms, optionally substituted cycloalkyl, optionally substituted phenyl, orR.sub.2 denotes ##STR2## in which R.sub.4 is hydrogen or optionally substituted (C.sub.1 -C.sub.4) alkyl and R.sub.5 is (C.sub.1 -C.sub.4)alkyl or optionally substituted phenylare effective as fungicides and growth regulators.

Description

This invention relates to novel 1,2,4-triazole derivatives, to their manufacture and their use as pesticides in plant protection and as agents for the regulation of growths of plants.

The compounds according to the invention have the formula I ##STR3## in which R.sub.1 denotes methyl or phenyl optionally substituted by halogen, (C.sub.1 -C.sub.4)alkyl, preferably (C.sub.1 -C.sub.2)alkyl, or (C.sub.1 -C.sub.4)alkoxy, preferably (C.sub.1 -C.sub.2)alkoxy and

R.sub.2 denotes the group R.sub.3 O-- in which R.sub.3 is alkyl, preferably having up to 12 carbon atoms and more preferably up to 8 carbon atoms, which may be substituted additionally by halogen, preferably chlorine or bromine, (C.sub.1 -C.sub.4)alkoxy or alkoxycarbonyl preferably having up to 8 carbon atoms, more preferably up to 5 carbon atoms; or is alkinyl preferably having up to 3 carbon atoms; or is cycloalkyl preferably having up to 6 carbon atoms and optionally substituted additionally by (C.sub.1 -C.sub.4)alkyl; or is phenyl optionally substituted by halogen or F.sub.3 C--, or R.sub.2 denotes ##STR4## in which R.sub.4 is hydrogen or (C.sub.1 -C.sub.4)alkyl optionally substituted by alkoxycarbonyl preferably having up to 8 carbon atoms, more preferably up to 5 carbon atoms and R.sub.5 is (C.sub.1 -C.sub.4)alkyl or phenyl optionally substituted by halogen, F.sub.3 C--, (C.sub.1 -C.sub.4)alkyl, (C.sub.1 -C.sub.4)alkoxy, phenoxy or halophenoxy.

In general, the compounds of formula I are obtained in the form of mixtures of cis/trans isomers which can be separated into the individual isomers by known methods.

The triazole derivatives of formula I can be produced by reacting a compound of the formula II ##STR5## in which R.sub.1 and R.sub.2 are as defined under formula I and Hal is chlorine or bromine, preferably chlorine, at elevated temperature, preferably of from 70.degree. to 140.degree. C. and more preferably 80.degree. to 110.degree. C., with 1,2,4-triazole in the presence of an agent binding hydrogen halide. The reaction is preferably carried out in an organic solvent, for example acetone, acetonitrile, dimethyl formamide or higher boiling hydrocarbons, for example xylene. To bind the hydrohalic acid formed in the reaction it proved advantageous to use an at least molar excess of the triazole or a corresponding amount of an inorganic or tertiary organic base, for example K.sub.2 CO.sub.3, Na.sub.2 CO.sub.3, triethylamine, pyridine or N,N-dimethylaniline.

The starting compounds of formula II which, for the most part, are also novel, can be produced in known manner from acid chlorides of the formula III ##STR6## by reaction with alcohols of the formula R.sub.2 OH or amines of the formula ##STR7## in which formulae R.sub.1, R.sub.2, R.sub.4, R.sub.5 and Hal are as defined under formulae I and II.

The carboxylic acid chlorides of formula III can be produced by processes known from literature, for example by reacting a .beta.-keto ester of the formula R.sub.1 --CO--CH.sub.2 --COOR with a chlorination agent (cf. JACS 77, 1137 (1955); J. Chem. Soc. 99, page 1621 (1911)).

The compounds of formula I are distinguished by a very good fungicidal effect. They can be used to combat curatively fungi that have already penetrated into the vegetal tissue. This is especially important and advantageous with fungal diseases which can no longer be combated with the usual fungicides once the infection has started. The compounds of the invention are effective, for example, against Phytophthora infestans, Plasmopara viticola, Venturia inaequalis, Cercospora betae and Tilletia tritici and above all, against types of genuine mildew in the cultivation of fruit, vegetable, cereals and vine and in horticulture. In part, they are also effective against rust fungi. It should be noted that the compounds of the invention have an outstanding effect against types of mildew that are resistant to benzimidazole derivatives, for example Benomyl and Carbendazim.

The compounds of formula I according to the invention can also be used in the technical field, for example in wood protecting agents, for paints, as preservatives, for example in lubricating cooling liquids for shaving metal. Moreover, some of the compounds exhibit a good effect against phytopathogeneous bacteria, the control of which increases in importance in horticulture and agriculture.

In biological experiments the compounds of formula I according to the invention exhibit very good growth regulating properties in a series of economically important plants. It should be noted especially that besides a general growth regulating effect, the compounds have a good growth inhibiting effect in cereals.

It has been proposed to regulate the growth of higher plants by the application of succinic acid 2,2-dimethylhydrazide, 2-chloroethyltrimethylammonium chloride and maleic acid hydrazide. The effect of these compounds is, however, not always satisfactory, for example, in that higher concentrations partially cause phytotoxic damages, the known compounds are ineffective in some important crop plants or the crop yield is impaired. In contradistinction thereto, the compounds of formula I according to the invention surprisingly exhibit an outstanding regulatory effect without phytotoxic damages occurring.

In plant protection the compounds of formula I can be used in the form of the usual formulations such as dusts, wettable powders, seed treating agents, dispersions, solutions, or emulsion concentrates. In general, the formulations contain from 2 to 95%, preferably 10 to 90% by weight of active compound of formula I. In addition, the formulations may contain the usual adhesives, wetting agents, dispersing agents, emulsifiers, penetration agents, solvents, fillers and carriers.

The following examples illustrate the invention.

(A) EXAMPLES OF PREPARATION

EXAMPLE 1

3-(1,2,4-Triazol-1-yl)-cinnamic acid-N-isopropyl-2',6'-dimethyl anilide ##STR8##

0.07 Mol (22.9 g) of 3-chloro-cinnamic acid N-isopropyl-2',6'-dimethyl anilide were dissolved in 90 ml of dimethyl formamide, 5.8 g (0.084 mol) of 1,2,4-triazole and 11.5 g of anhydrous potassium carbonate were added and the whole was kept for 6 hours at 100.degree. C. while stirring. After cooling of the reaction mixture and pouring into iced water, it was extracted with methylene chloride and the organic phase was washed with water. After removal of the methylene chloride under reduced pressure, 23.6 g of an amber-colored, semicrystalline product were obtained which, according to thin layer chromatography, consisted of approximately equal parts of cis- and trans-isomer of 3-(1,2,4-triazol-1-yl)-cinnamic acid N-isopropyl-2',6'-dimethyl anilide.

Yield 23.6 g=93.5% of the theory. Thin layer chromatogram: R.sub.f 0.4 and 0.5. (pre-fabricated plates of silica gel 60 F.sub.254 of Messrs. Merck). eluent: ethyl acetate. Analysis: C.sub.22 H.sub.24 N.sub.4 O; MW 360.4. calculated C 73.30%; H 6.71%; N 15.54%. found C 73.2%; H 6.7%; N 15.5%.

After recrystallization of a sample of toluene/gasoline, colorless crystals melting at 160.degree. to 161.degree. C. and having correct analytical values were obtained. NMR spectrum and thin layer chromatogram indicated a strong enrichment of one of the two isomers.

EXAMPLE 2

3-(1,2,4-Triazol-1-yl)-4'-chloro-cinnamic acid isobutyl ester ##STR9##

0.07 Mol (19.1 g) of 3-chloro-4'-chlorocinnamic acid isobutyl ester was reacted with 1,2,4-triazole under the conditions of Example 1. After working up, a honeycolored viscous sirup was obtained which, according to thin layer chromatography (eluent toluene/ethyl acetate 2:1); R.sub.f values 0.38 and 0.45 consisted of a mixture of cis- and trans-isomers of 3-(1,2,4-triazol-1-yl)-4'-chlorocinnamic acid isobutyl ester.

Yield 19.5 g=91% of the theory. Analysis: C.sub.15 H.sub.16 ClN.sub.3 O.sub.2 ; MW 305.7. calculated C 58.92%; H 5.27%; N 13.74%. found C 58.6%; H 5.0% N 13.5%.

EXAMPLE 3

3-(1,2,4-Triazol-1-yl)-crotonic acid isobutyl ester ##STR10##

0.1 Mol (17.7 g) of 3-chlorocrotonic acid isobutyl ester in 100 ml acetonitrile, 012 mol (8.3 g) of 1,2,4-triazole and 0.12 mol (16.5 g) of anhydrous potassium carbonate were refluxed for 5 hours. After removal of the solvent under reduced presure, the reaction mixture was cooled, water was added and the resulting mixture was extracted with methylene chloride. After distillation of the methylene chloride under reduced pressure, the 3-(1,2,4-triazol-1-yl)-crotonic acid isobutyl ester was obtained in the form of a weakly yellow oil.

Yield 18.2 g=87% of the theory. Thin layer chromatogram (toluene/ethyl acetate 2:1). R.sub.f 0.2. Analysis: C.sub.10 H.sub.15 N.sub.3 O.sub.2 ; MW 209.2. calculated C 57.40%; H 7.23%; N 20.08%. found C 57.1%; H 7.3%; N 19.8%.

EXAMPLES 4 to 90

Examples 4 to 6 were carried out in the manner described in Example 3 while Examples 7 to 90 were carried out under the conditions of Example 1. In the following table are indicated the radicals R.sub.1 and R.sub.2 of the compounds prepared from corresponding compounds of formula II and the melting points or the refractive index of said compounds.

TABLE 1__________________________________________________________________________ ##STR11## formula IExampleNo. R.sub.1 R.sub.2 m.p. (.degree.C.)__________________________________________________________________________4 CH.sub.3 ##STR12## 106-1075 CH.sub.3 (CH.sub.3).sub.2 CHO 42-44 0.3/1056 CH.sub.3 CH.sub.3 (CH.sub.2).sub.3 O oil ##STR13## CH.sub.3 O 74-888 ##STR14## C.sub.2 H.sub.5 O oil9 ##STR15## (CH.sub.3).sub.2 CHO 0,3/14710 ##STR16## CH.sub.3 CH.sub.2 CH.sub.2 O oil11 ##STR17## (CH.sub.3).sub.2 CHCH.sub.2 O oil12 ##STR18## CH.sub.3 (CH.sub.2).sub. 3 O oil13 ##STR19## (CH.sub.3).sub.3 CO semi- crystalline14 ##STR20## ##STR21## oil15 ##STR22## ##STR23## oil16 ##STR24## CHCCH.sub.2 O oil17 ##STR25## ##STR26## 99-11518 ##STR27## ##STR28## 108-121 (138-140).sup.(+)19 ##STR29## N(C.sub.2 H.sub.5).sub.2 oil20 ##STR30## N(CH.sub.2 CH.sub.2 CH.sub.3).sub.2 oil21 ##STR31## N[CH(CH.sub.3).sub.2 ].sub.2 150-15122 ##STR32## ##STR33## 160-16223 ##STR34## ##STR35## 243-255 (265-266).sup.(+)24 ##STR36## ##STR37## sirup25 ##STR38## ##STR39## oil26 ##STR40## ##STR41## oil27 ##STR42## ##STR43## sirup28 ##STR44## ##STR45## sirup29 ##STR46## ##STR47## 113-11930 ##STR48## ##STR49## sirup31 ##STR50## ##STR51## semi- crystalline32 ##STR52## ##STR53## sirup33 ##STR54## ##STR55## sirup34 ##STR56## O(CH.sub.2).sub.2 CH.sub.3 semi- crystalline35 ##STR57## OCH(CH.sub.3).sub.2 oil36 ##STR58## O(CH.sub.2).sub.3 CH.sub.3 semi- crystalline (100-104).sup.(+)37 ##STR59## OC(CH.sub.3).sub.3 sirup38 ##STR60## ##STR61## 104-122 (122-133).sup.(+)39 ##STR62## ##STR63## sirup40 ##STR64## ##STR65## sirup41 ##STR66## ##STR67## semi- crystalline (163-164).sup.(+)42 ##STR68## ##STR69## sirup43 ##STR70## ##STR71## 129-15744 ##STR72## ##STR73## sirup45 ##STR74## OCH.sub.3 117-12246 ##STR75## OC.sub.2 H.sub.5 semi- crystalline47 ##STR76## ##STR77## 105-13548 ##STR78## O(CH.sub.2).sub.3 CH.sub.3 sirup49 ##STR79## ##STR80## sirup50 ##STR81## ##STR82## sirup51 ##STR83## N(CH.sub.2 CH.sub.2 CH.sub.3).sub.2 117-12052 ##STR84## O(CH.sub.2 ).sub.3 CH.sub.3 oil53 ##STR85## ##STR86## sirup54 ##STR87## O(CH.sub.2).sub.4CH.sub.3 sirup55 ##STR88## O(CH.sub.2).sub.5CH.sub.3 semicrystalline56 ##STR89## ##STR90## sirup__________________________________________________________________________ n.sub.D.sup.30 (refractive index; not me-Example asured with viscous sirupyNo. R.sub.1 R.sub.2 products)__________________________________________________________________________57 ##STR91## ##STR92## 1.577958 ##STR93## ##STR94## 1.579859 ##STR95## ##STR96## 1.592660 ##STR97## ##STR98## 1.585961 ##STR99## ##STR100## 1.568862 ##STR101## ##STR102## 1.575563 ##STR103## ##STR104## 1.576864 ##STR105## ##STR106## 1.584365 ##STR107## ##STR108## 1.553266 ##STR109## OCH(CH.sub.3).sub.2 1.558767 ##STR110## ##STR111## 1.550168 ##STR112## O(CH.sub.2).sub.2 CH.sub.3 1.560269 ##STR113## OCH(CH.sub.3).sub.2 1.558370 ##STR114## OCH.sub.2 CH(CH.sub.3).sub.2 1.537271 ##STR115## O(CH.sub.2).sub.2 CH.sub.3 1.568272 ##STR116## ##STR117## 1.581273 ##STR118## ##STR119## 1.586374 ##STR120## ##STR121## sirup75 ##STR122## ##STR123## sirup76 ##STR124## ##STR125## sirup77 ##STR126## ##STR127## semicrystalline78 ##STR128## ##STR129## semicrystalline79 ##STR130## ##STR131## sirup80 ##STR132## ##STR133## 1.532881 ##STR134## ##STR135## sirup82 ##STR136## ##STR137## semicrystalline83 ##STR138## ##STR139## sirup84 ##STR140## ##STR141## sirup85 ##STR142## ##STR143## sirup86 ##STR144## O(CH.sub.2).sub.7 CH.sub.3 semicrystalline87 ##STR145## O(CH.sub.2).sub.2 OC.sub.2 H.sub.5 sirup88 ##STR146## O(CH.sub.2).sub.3 Cl sirup89 ##STR147## ##STR148## 1.578990 ##STR149## ##STR150## semicrystalline__________________________________________________________________________ .sup.(+) melting point of samples recrystallized from toluene/hexane

(B) EXAMPLES OF FORMULATION

EXAMPLE A

A dusting powder is obtained by mixing

10 parts by weight of active substance and 90 parts by weight of talc as inert material and comminuting the mixture in a hammer mill.

EXAMPLE B

A wettable powder which is easily dispersible in water is obtained by mixing

25 parts by weight of active substance 64 parts by weight of quartz containing kaolin as inert material 10 parts by weight of potassium lignosulfonate and 1 part by weight of sodium oleoyl-methyl-tauride as wetting and dispersing agent and grinding the mixture in a pin mill.

EXAMPLE C

A dispersion concentrate readily dispersible in water is obtained by mixing

20 parts by weight of active substance 6 parts by weight of nonylphenol polyglycol ether (10 EO) 3 parts by weight of isotridecanol polyglycol ether (8 EO) and 71 parts by weight of paraffinic mineral oil (boiling range 255.degree. to >377.degree. C. at atmospheric pressure) and grinding the mixture in a ball mill to a particle size below 5 microns.

EXAMPLE D

An emulsifiable concentrate is obtained from 15 parts by weight of active substance 75 parts by weight of cyclohexanone as solvent, and 10 parts by weight of oxethylated nonyl phenol (10 EO) as emulsifier.

(C) BIOLOGICAL EXAMPLES

EXAMPLE I

Wheat plants in the three-leaf stage were strongly infested with conidia of powdery mildew of cereals (Erysiphe graminis) and then kept in the greenhouse at 20.degree. C. and a relative atmospheric humidity of 90 to 95%. 3 Days after infestation, the plants were sprayed to the drip off with spray liquors containing the compounds indicated in Table I in concentrations of 500, 250, 125, 60, 30 and 15 mg of active substance per liter. As comparative agent Maneb was used. After a time of incubation of 10 days, the plants were examined as to their degree of infestation with mildew, which is indicated in the table in % of infested leaf area with respect to untreated but infested control plants (100% infestation).

The results are indicated in Table I.

TABLE I______________________________________ leaf surface in percent infested with powdery mildew after treatment with mg of active sub-Compound stance per liter of spray liquorof Ex. No. 500 250 125 60 30 15______________________________________13 0 5 15 2511 0 5 15 25 9 0 3-5 10 1510 0 5 15 2512 0-3 5 15 2520 0-3 3 10 1514 0-3 3 5 1027 0 0 0 5 10-15 1 0 0 3-5 10 15 2 0 0 0 3-5 1035 0 0 0 0 534 0 0 0 0 0-3 3-537 O 0 0 0 3 581 0 0 0 0 3 589 0 0 0 0 3 580 0 0 0 0 0 078 0 0 0 0 0 075 0 0 0 0-3 5 1574 0 0 0 0 5 1073 0 0 0-3 15-10 15 2590 0 0 0 0 3 5Maneb* 5 10 15 25untreated infested plants 100______________________________________ *Maneb = manganous ethylene bisdithiocarbamate

EXAMPLE II

Cucumber plants of the type Delikatess in the two-leaf stage were strongly infested with a conidia suspension of cucumber mildew (Erysiphe cichoracearum). The spore suspension was allowed to dry on the plants for 30 minutes, whereupon they were transferred to the greenhouse having a temperature of 22.degree. C. and a relative humidity of 90%. 3 Days after infestation the plants were sprayed to the drip off with spray liquors of the compounds listed in Table II in the indicated concentrations. As comparative agent Maneb was used. The plants were inspected as to their degree of infestation 10 days after the treatment. The degree of infestation is expressed in % of infested leaf area, relative to untreated but infested control plants (100% infestation). The results are indicated in Table II.

TABLE II______________________________________ leaf surface in percent infested with cucumber mildew after treatment with mg of active sub-Compound stance per liter of spray liquorof Ex. No. 500 250 125 60 15 8______________________________________13 0 3-5 10 1511 0 3-5 5-10 15 9 0 3-5 10 15-2510 0 3-5 15 2512 0 3 3 5-1020 0-3 5 10 1514 0 0-3 5 10-1525 0 0-3 5 10-1527 0 0 0 0-3 5-10 1 0 0 0 0 0-3 2 0 0 0 0 335 0 0 0 0 0 590 0 0 0 0 381 0 0 0 0 389 0 0 0 0 380 0 0 0 0 078 0 0 0 0 075 0 0 0 0 0-374 0 0 0 0 0-373 0 0 0 0 0-3Maneb* 15 25 35 60 100untreated infested plants 100______________________________________ *Maneb = manganous ethylene bisdithiocarbamate

EXAMPLE III

Cucumber plants of the type Delikatess in the two-leaf stage were strongly infested with a conidia suspension of Benomyl-resistant cucumber mildew (Erysiphe cichoracearum). The spore suspension was allowed to dry on the plants for 30 minutes, whereupon they were transferred to the greenhouse having a temperature of 22.degree. C. and a relative humidity of 90%. 3 Days after infestation the plants were sprayed to the drip off with spray liquors of the compounds listed in Table III in the indicated concentrations. As comparative agent Maneb was used. The plants were inspected as to their degree of infestation 10 days after the treatment. The degree of infestation is expressed in % of infested leaf area, relative to untreated but infested control plants (100% infestation). The results are indicated in Table III.

TABLE III______________________________________ leaf area infested with cucumber mildew (strain resistant to Benomyl) in % with mg ofCompound active substance per liter of spray liquorof Ex. No. 500 250 125 60 15 7______________________________________13 0 3-5 10 1511 0 5 5-10 15 9 0 5 10 1510 0 3-5 15 2512 0 0 0-3 15-2520 0 0-3 3-5 1514 0 3 5-10 1525 0 0 3-5 5-1027 0 0 0 3 5 10 1 0 0 0 0 3-5 5 2 0 0 0 0 3-5 535 0 0 0 0 0 390 0 0 0 0 3-581 0 0 0 0 389 0 0 0 0 380 0 0 0 0 078 0 0 0 0 0-375 0 0 0 0 3-574 0 0 0 0 3-573 0 0 0 0 3Maneb* 15 25 35 60 100 100untreated infested plants 100______________________________________ *Maneb = manganous ethylene bisdithiocarbamate

EXAMPLE IV

Barley plants in the three-leaf stage were strongly infested with conidia of powdery mildew of cereals (Erysiphe graminis sp. hordei) and kept in the greenhouse at 20.degree. C. and a relative humidity of 90 to 95%. Three days after infestation the plants were sprayed to the drip off with spray liquors of the compounds listed in Table IV in concentrations of 500, 250, 125, 60 and 30 mg per liter of spray liquor. Maneb was used for comparison. After a time of incubation of 10 days, the plants were examined as to the degree of infestation with mildew. The degree of infestation is expressed in percent of infested leaf area relative to untreated but infested control plants (100% infestation). The results are summarized in Table IV.

TABLE IV______________________________________ leaf surface in percent infested with powdery mildew after treatment with mg of active sub-Compound stance per liter of spray liquorof Ex. No. 500 250 125 60 30______________________________________13 0 5-10 15 2511 0 3 5-10 15 9 0 3-5 10 2510 0 3 10-15 25 8 0-3 10 15 2512 0 5-10 15 2520 0-3 5-10 15 2514 0 5-10 15 2525 0-3 10-15 25 3527 0 0 0 3-5 10 1 0 0 0 0 3-5 2 0 0 0 0 3-535 0 0 3 3-5 534 0 0 0-3 5-10 1537 0 0-3 3-5 10 15-2590 0 0 0 0 381 0 0 0 0 0-389 0 0 0 0 3-580 0 0 0 0 078 0 0 0 0 075 0 0 0 0-3 574 0 0 0 0-3 3-573 0 0 0 0-3 3Maneb* 25 35 60 100 100untreated infested plants 100______________________________________ *Maneb = manganous ethylene bisdithiocarbamate

EXAMPLE V

Apple stocks of the type EM IX in the four-leaf stage were strongly infested with a conidia suspension of powdery mildew of apple (Podosphaera leucotricha). The plants were cept for 16 hours in a climatic chamber having a temperature of 20.degree. C. and a relative humidity of about 100% and then transferred to the greenhouse where the temperature was 22.degree. C. and the relative humidity amounted to 85%. Three days after infestation the plants were sprayed to the drip off with the compounds listed in Table V in the indicated concentrations. Maneb was used for comparison. After 2 to 3 weeks the plants were inspected as to the degree of infestation with mildew, which is expressed in the table in % of infested leaf surface, relative to untreated but infested control plants (=100%). The results are summarized in Table V.

TABLE V______________________________________ leaf surface infested with apple mildew in % with mg of active substance per literCompound of spray liquorof Ex. No. 1000 500 250 125______________________________________12 0 0-3 5 1514 0 0-3 5 2527 0-3 3 5 15 1 0-3 3 5-10 15-25 2 0 0-3 3-5 535 0 0-3 5 5Maneb* 25 35 60 100untreated infested plants 100______________________________________ *Maneb = manganous ethylene bisdithiocarbamate

EXAMPLE VI (growth inhibition)

In tray tests in the greenhouse young plants of cereals (wheat, barley and rye) in the three-leaf stage were sprayed to the drip off with spray liquors of the compounds listed in Table VI in the indicated concentrations (kg/hectare). 2-Chloroethyltrimethylammonium chloride, maleic acid hydrazide and succinic acid 2,2-dimethylhydrazide were used for comparison. When the untreated control plants had reached a height of growth of about 55 cm, the growth of all plants was measured and the inhibition was calculated in percent of the growth of the control plants. In addition, the phytotoxic effect of the compounds was examined. The results are indicated in Table VI, in which an inhibition of growth of 100% means no growth at all while 0% inhibition corresponds to the growth of the untreated control plants.

TABLE VI__________________________________________________________________________Inhibition of growth in cereals concentra- tion of of activeCompound substance % inhitition of growth phytotoxicof Ex. No. kg/ha wheat barley rye effect__________________________________________________________________________127 2.5 33 29 26 no damage 1.25 30 28 10comparison 2.5 27 8 10 no damage(2-chloroethyl)-trimethyl- 1.25 23 0 0ammonium chloridecomparison 2.5 37 35 38 heavy damagemaleic acid hydrazide 1.25 20 20 29comparison 2.5 0 0 0 no damagesuccinic acid 2,2-dimethyl- 1.25 0 0 0hydrazide__________________________________________________________________________

Claims

1. A 1,2,4-triazole derivative of the formula I ##STR151## in which R.sub.1 denotes methyl or phenyl optionally substituted by halogen, (C.sub.1 -C.sub.4)alkyl or (C.sub.1 -C.sub.4)-alkoxy, and

R.sub.2 denotes the group R.sub.3 O-- in which R.sub.3 is alkyl, having up to 12 carbon atoms, which may be substituted additionally by halogen, (C.sub.1 -C.sub.4)alkoxy or alkoxycarbonyl having up to 8 carbon atoms; or is alkinyl having up to 3 carbon atoms; or is cycloalkyl having up to 6 carbon atoms and optionally substituted additionally by (C.sub.1 -C.sub.4)alkyl; or is phenyl optionally substituted by halogen or F.sub.3 C--, or

R.sub.2 denotes ##STR152## in which R.sub.4 is hydrogen or (C.sub.1 -C.sub.4)-alkyl optionally substituted by alkoxycarbonyl having up to 8 carbon atoms, and R.sub.5 is (C.sub.1 -C.sub.4)alkyl or phenyl optionally substituted by halogen, F.sub.3 C--, (C.sub.1 -C.sub.4)alkyl, (C.sub.1 -C.sub.4)alkoxy, phenoxy or halophenoxy.

2. A pesticidal composition having fungicidal activity comprising a carrier or suitable auxiliary and as an active ingredient a compound as defined in claim 1.

3. The composition of claim 2 wherein said compound is present in an amount of from 2 to 95% by weight of said composition.

4. A pesticidal composition having plant growth regulating activity comprising a carrier or suitable auxiliary and as an active ingredient a compound defined in claim 1.

5. The composition of claim 4 wherein said compound is present in an amount of from 2 to 95% by weight of said composition.

6. A method of controlling plant infestation which comprises treating said plants with a compound as defined in claim 1.

7. A method of regulating plant growth which comprises treating said plants with a compound as defined in claim 1.

8. A method of inhibiting growth in cereals which comprises treating said cereals with a compound as defined in claim 1.