SE469585B - COMPOSITION TO CONTROL GROWTH BY CEREALY PLANT BY ASTADCOMMATIVE SELECTIVE HANDLING STERILITY CONTAINING AS ACTIVE INGREDIENT CERTAIN 1-ARYL-1,4-DIHYDRO-4-OXOPYRIDAZINES - Google Patents

Description

According to the invention there is provided a composition of the kind mentioned in the introduction, which is characterized in that it contains a carrier which can be contracted in an agricultural context and as active ingredient a compound of the formula O (I) H5 equal to 2 wherein R 1 is carboxy, or an agriculturally tolerable salt thereof, or alkoxycarbonyl having up to 12 carbon atoms in the alkoxy moiety R2 is a phenyl or substituted phenyl having up to 3 substituents which are collectively, in the case of carbonaceous substituent (s), has a total of from 0 to 6 carbon atoms, the substituent or substituents being selected from (1) alkyl, (2) C 4 H 4 = forming a naphthyl group, (3) alkoxy, (4) halogen, (5) nitro, (6) trifluoromethyl, (7) ) alkanoyloxy and (8) alkylthio, R 3 is (C 1 -C 4) -alkyl and R 4 is hydrogen, (C 1 -C 4 -alkyl or halogen. According to a preferred embodiment of the invention, R 1 is a carboxy group or an alkali metal salt thereof, while R 3 is a methyl group, R 4 is a hydrogen atom and R 2 is a 4-chlorophenyl group.

When R 1 is a salt of a carboxy group, an alkali metal, alkaline earth metal or transition metal may form the cation. The cation can also be an ammonium or substituted ammonium group. Representative examples of metal salt cations include alkali metal cations which are preferred, such as sodium, potassium and lithium; alkaline earth metal cations, such as calcium, magnesium, barium and strontium, or heavy metal cations, such as zinc, manganese, copper, cupro, ferric, ferrous, titanium and aluminum. Among the ammonium salts may be mentioned those 464 585 3 wherein the ammonium cation has the formula NZ1Z2Z3Z4 wherein Z1 Z2 Z3 I 1, and Z4 (which may be the same or different) represent wheat, hydroxy, (C1-C4) -alkoxy, (C1-C20) -alkyl , (C3-C8) -alkenyl, (C3-C8) -alkynyl, (C2-C8) -hydroxyalkyl, alkoxyalkyl having from 2 to 5 carbon atoms, (c2-c6) -aminoalkyl, (c2-c6) -halo1 alkyl, substituted or unsubstituted phenyl, substituted or unsubstituted phenylalkyl having up to 4 carbon atoms in the alkyl moiety, amino or alkyl-substituted amino. Alternatively, any two of the groups Z1, Z2, Z3 and Z4 may be combined to form, together with the nitrogen atom, a 5- or 6-membered heterocyclic ring, which optionally has up to an additional heteroacid, nitrogen or sulfur atom in the ring and which is preferably saturated, such as in a piperidine, morpholine, pyrrolidine or piperazine ring. Another alternative is that any three of the groups Z1, Z2, Z3 and Z4 may be combined to form, together with the nitrogen atom, a 5- or 6-membered aromatic heterocyclic ring, such as a pyrrole or pyridine ring. . When the ammonium group contains a substituted alkyl, substituted phenyl or substituted phenylalkyl group, the substituents are usually selected from halogen, (C 1 -C 8) -alkyl, (C 1 -C 4) -alkoxy, hydroxy, nitro, trifluoromethyl, cyano, amino and (C1-C4) -alkylthio. Such substituted phenyl groups preferably have up to two such substituents. Representative examples of ammonium cations include ammonium, dimethylammonium, 2-ethylhexylammonium, bis (2-hydroxyethyl) ammonium, tris (2-hydroxyethyl) ammonium, dicyclohexylammonium, t-octylammonium, 2-hydroxyethylammonium, morpholinium, piperolinium , 2-phenethylammonium, 2-methylbenzylammonium, n-hexylammonium, triethylammonium, trimethylammonium, tri (n-butyl) ammonium, methoxyethylammonium, diisopropylammonium, pyridinium, diallylammonium, pyrazolium, propargylammoniumammonium, propargylammoniumammonium , octadecylammonium, 4-dichlorophenylammonium, 4-nitrobenzylammonium, benzyltrimethylammonium, 2-hydroxyethyldimethyloctadecylammonium, 2-hydroxyethyldietyloctylammonium, decyltrimethylammonium, hexyltriethylammonium and 4-methylmethylbenzylammonium. Typical compounds within the scope of the invention are, for example: 1-phenyl-1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid, 1- (4-chlorophenyl) -1,4-dihydro-4- oxo-6-methylpyridazine-3-carboxylic acid, 1- (4-fluorophenyl) -1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid, 1- (4-bromophenyl) -1, 4-Dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid, 1- (4-iodophenyl) -1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid, 1- (3 -fluorophenyl) -1,4-dihydro-4-xo-6-methylpyridazine-3-carboxylic acid, 1- (3-chlorophenyl) -1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid boxylic acid, 1- (3-bromophenyl) -1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid, 1- (3,4-dichlorophenyl) -1,4-dihydro-4-oxo- 6-methylpyridazine-3-carboxylic acid, 1- (2-fluorophenyl) -1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid, 1- (2-chlorophenyl) -1,4-dihydro- 4-oxo-6-methylpyridazine-3-carboxylic acid, 1- (4-trifluoromethylphenyl) -1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid, 1- (3-trifluoromethylphenyl) -1, 4-Dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid, 1-phenyl-1,4-dihydro-4-oxo-6-ethyl Pyridazine-3-carboxylic acid, 1- (4-chlorophenyl) -1,4-dihydro-4-oxo-6-ethylpyridazine-3-carboxylic acid, 1- (4-fluorophenyl) -1,4-dihydro-4- oxo-6-ethylpyridazine-3-carboxylic acid, 1- (3,4-dichlorophenyl) -1,4-dihydro-4-oxo-6-ethylpyridazine-3-carboxylic acid, 1-phenyl-1,4-dihydro- 4-oxo-6-propylpyridazine-3-carboxylic acid, 1-phenyl-1,4-dihydro-4-oxo-5,6-dimethylpyridazine-3-carboxylic acid, 1- (4-chlorophenyl) -1,4- dihydro-4-oxo-5,6-dimethylpyridazine-3-carboxylic acid, 469,585 1-phenyl-1,4-dihydro-4-oxo-5-ethyl-6-methylpyridazine-3-carboxylic acid, 1-phenyl -1,4-dihydro-4-oxo-5,6-diethylpyridazine-3-carboxylic acid, 1- (4-methylphenyl) -1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid, 1 - (2-chloro-4-methylphenyl) -1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid, 1- (2,4,6-trichlorophenyl) -1,4-dihydro-4-oxo -6-methylpyridazine-3-carboxylic acid, 1- (3-ethoxyphenyl) -1,4-dihydro-4-oxo-6-ethylpyridazine-3-carboxylic acid, 1- (4-methylthiophenyl) -1,4-dihydro -4-oxo-6-methylpyridazine-3-carboxylic acid, 1-phenyl-5-bromo-1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid 1- (3-chlorophenyl) -5-chloro-1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid, 1- (4-chlorophenyl) -5-bromo-1,4-dihydro- 4-oxo-6-ethylpyridazine-3-carboxylic acid, and the salts of the above acids.

The compounds (I) used according to the invention can be prepared by methods which are per se known for analogous compounds or other methods which may be conceived for this purpose. According to a suitable method, a 4-hydroxy-2-pyrone of formula (II) is reacted wherein R 6 is a hydrogen atom or an alkyl group and R 3 is as defined above, or a salt of a pyrone of formula II (prepared by treating the pyrone with a equivalent of a suitable aqueous base, such as potassium or sodium hydroxide, acetate or carbonate), usually at a temperature of from -10 to 50 ° C, in a polar solvent, such as water, methanol, ethanol, glyme or dimethylformamide, with a diazonium salt, such as diazonium chloride, prepared by conventional diazotization techniques of an amine of the formula 2 R - NH (III) 2 wherein R 2 is as defined above. The product hydrazone having the formula (IV) 3 and R 6 having the meaning given above is treated wherein R 2, R 2 are then treated with either an aqueous acid such as hydrochloric acid, trifluoroacetic acid, sulfuric acid, methanesulfonic acid or nitric acid, or an aqueous base such as sodium carbonate or sodium hydroxide. , usually at a temperature of from 20 to 150 ° C and preferably from 40 to 100 ° C, to form (by rearrangement) a pyridazine of the formula CO H (V) wherein R 2, R 3 and R 6 are as defined above.

Esters of the pyridazine of formula V are prepared by esterification with a suitable alcohol, preferably a (C1-C4) alkanol. A conventional technique is a Fischer esterification, in which anhydrous hydrochloric acid or sulfuric acid is used as catalyst and the alcohol as solvent. This esterification is usually carried out at a temperature of from 150 ° C to 150 ° C, optionally using an inert co-solvent such as methylene chloride, ethylene chloride, diethyl ether, toluene or xylene. Salts of the pyridazines of formula V and their 5-halo analogs may be prepared by conventional techniques, such as by neutralization with a suitable inorganic or organic base, in a solvent such as water or methanol.

The compounds used according to the invention, wherein R is a halogen atom, can be prepared by reacting pyridazines of formula V, wherein R 6 is a hydrogen atom, with one equivalent of a halogenating agent, such as bromine, chlorine, sulfuryl bromide or sulfuryl chloride, or the like in a suitable inert solvents such as hexane, benzene, ethylene dichloride or methanol, usually at a temperature of from 0 to 50 ° C and preferably at room temperature.

Table I lists typical compounds for use according to the invention as well as their melting points and elemental analyzes.

The concrete preparations following Table I show the synthesis of compounds 10, 12, 14 and 16 in Table I, and in these preparations all temperatures refer to ° C, while parts and percentages refer to parts by weight and percent by weight, respectively, unless otherwise indicated. . 469 585 8 Table I 1-aryl-1,4-dihydro-4-oxo-pyridazines 0 R 4 CO 2 H 2 14 3 / CH; N X Compound Ä, O no: R X M.p. (C)% C% H,% N% Hal 1 H 5-F 215-5 Ber. 58.06 5.65 11.29 7.65 Found 58.07 5.60 11.55 7.68 2 H 4-0H5, 202-5 56.22 5.65 10.09 12.77 3-Cl 55 .92 3.84 10.90 13.36 5 H 4-I 241-2 40.47 2.55 7.87 55.64 _ 41.20 2.46 .05 55.67 4 H 4-Br 245 46 , 62 2.95 9.06 25.85 47.45 5.14 9.26 25.64 5 H 4-CF3 254-5 52.55 5.04 9.40 19.11 '51.99 2.97 9.13 18.94 6 H 4-NO2 244-5 52.57 5.50 15.27 - __ 7 H 4-CH 162-5 65.92 4.95 11.47 - 5 65.66 4 , 89 11.52 - 8 H 2.5- 218-20 61.06 5.52 8.90 11.27 -ben- 61.07 5.42 8.86 11.00 s0-4-. -01 9 H 4-0cH 169-70 59.94 4.64 10.77 - 3 0.14 4.62 10.82 - 10 H 4-F 185-7 58.06 5.65 11.29 7.65 58.73 3.64 11.74 7.47 11 H 5.4- 220-2 48.18 2.69 9.57 23.71 dic1 48.05 2.75 9.21 25.96 12 H 4-C1 229-30 54.45 3.43 10.59 13.39 54.49 3.44 10.44 13.59 15 H 5-01 192-5 - - -: I 14 HH 175 - - - 15 Br 4-cH3 241 48.51 5.45 8.67 24.75 49.37 3.59 9.25 23.65 469 585 Table I §forts2 Association Ä O no: RX m.p. (C)% C% H% N% Ha1 16 Br 4-F 219-20 Ber. 44.06 2.46 8.57 24.43 * Burner 44.50 2.52 9.00 24.26 17 Br 4-Br zso ° 57.14 2.08 7.22 41.19 18 Br H zz0 ° 46.62 2.95 9.06 25.85 46.68 2.88 9.25 25.62 19 Cl 4-Br- 255-9 41.95 2.55 8.16 25, 26 ”41.65 2 , 51 7.74 23.17 x% Br; % F: ber. 5.81; found 5.83 * X% Br; % F; ber. 10.37; found 9.91.

Preparation 1 (Compound 10, Table I) Preparation of 1- (4-fluorophenyl) -1,4-dihydro-4-oxo-6-methylgyridazine-3-carboxylic acid 4-hydroxy-6-methyl-2-pyrone ( 7.88 g) is suspended in 250 ml of water, and 6.63 g of anhydrous sodium carbonate are added to the suspension to effect dissolution of the pyrone.

In a separate flask, mix 7.22 g of 4-fluoroaniline with 25 ml of concentrated hydrochloric acid and 31 ml of water. The resulting solution is maintained at about 5-10 ° and a solution of 4.75 g of sodium nitrite in 16 ml of water is added. The resulting solution of 4-fluorophenyldiazonium chloride is added dropwise to the stirred pyrone solution, while maintaining the temperature at about 5 to 10 ° and the pH at about 8 to 9 by adding small amounts of aqueous sodium hydroxide solution.

The hydrazone formed is refluxed for about 2 hours with 469,585 500 ml of concentrated hydrochloric acid. Coating and filtration give 10.2 g of 1- (4-fluorophenyl) -1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid, which is recrystallized from chloroform / ether (m.p. 185-7 °). Preparation 2 (Compound 12, Table I) = Preparation of 1- (4-chlorophenyl) -1,4-dihydro-4-oxo-6-methylpyridazine-carbogyl acid and its sodium salt p-chloroaniline (12.75 g) is dissolved in 40 ml of concentrated hydrochloric acid and cooled to 0 °, and to the solution thus obtained is added a solution of 7.6 g of sodium nitrite at a temperature of between 0 and 5 °. The diazotized aniline is added under ice-cooling to a previously prepared solution of 12.6 g of 4-hydroxy-6-methyl-2-pyrone and 55 g of sodium carbonate in 500 ml of water.

The slurry formed is heated under reflux overnight. When complete reaction is not observed, the pH is adjusted to 12 and refluxing is continued. The dark solution is neutralized to pH 6-7 with acetic acid and treated with activated charcoal. The filtrate is acidified to pH 2 with concentrated hydrochloric acid under ice-cooling to precipitate the product. The acid is recrystallized from acetone / hexane to give 10.5 g (39%) of 1- (4-chlorophenyl) -1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid (m.p. 229-230 ° C).

The acid (5.0 g) is converted to the sodium salt by treatment with 0.76 g of sodium hydroxide in 200 ml of anhydrous methanol. The solvent is removed and the solid is washed with ether and dried in vacuo at 90 ° C. Analysis calculated for C 12 H 8 ClN 2 ONa.1 / 2 H 2 O: C, 48.75; H, 3.07; N, 9.48; Cl, 11.99; Na, 7.78. Found: C, 48.11; H, 2.80; N, 9.24; Cl, 12.37; Na, 7.62.

Preparation 3 (Compound 14, Table I) Preparation of 1-phenyl-1,4-dihydro-4-oxo-6-methylpyridazine-3-carbogyl acid 469 585 μl In 375 ml of water 11.8 g of 4-hydroxy-6- are suspended. methyl 2-pyrone, and 9.95 g of anhydrous sodium carbonate are added to dissolve the pyrone.

In a separate flask, mix 9.08 g of aniline with 37.5 ml of concentrated hydrochloric acid and 47 ml of water. The resulting solution is maintained at about 5 to 10 °, and a solution of 7.13 g of sodium nitrite in 24 ml of water is added. The resulting solution of phenyldiazonium chloride is added dropwise to the stirred pyrone solution, while maintaining the temperature at about 5 to 10 °. The pH is maintained at about 8 to 9 by the addition of small amounts of sodium hydroxide solution.

After the addition is complete, the hydrazone obtained (18 g) is isolated by filtration and resuspended in 500 ml of concentrated hydrochloric acid. The mixture is refluxed for 2 1/2 hours and then cooled. The 1-phenyl-1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid precipitates as brown crystals, which are recrystallized from water. Yield -7.0 g; m.p. -173 °.

Preparation 4 (Compound 16, Table I) Preparation of 1- (4-fluorophenyl) -5-bromo-1,4-dihydro-4-ogg; methylpyridazine-3-carboxylic acid 1- (4-fluorophenyl) -1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid (1.5 g) is suspended in 100 ml of dry methanol and 0.242 g of sodium hydroxide is added . To the solution is added dropwise 1.038 g of bromine dissolved in 50 ml of methanol. The solvent is removed leaving a white solid, which is taken up in dilute base, and the solution is acidified with hydrochloric acid.

The precipitate formed is filtered off and recrystallized from chloroform / ether to give 1.4 g of 1- (4-fluorophenyl) -5-bromo-1,4-dihydro-4-oxo-6-methylpyridazine-3-carboxylic acid (m.p. 219 -20 °).

When used as chemical hybridizers, the compounds (I) effectively cause a high degree of selective male sterility, i.e. without simultaneously causing appreciable female sterility, in the treated plants and without causing appreciable inhibition of the growth of the treated plants. As the term "male sterility" is used in the present case, it is intended to include both actual male sterility, which is expressed in the absence of male flower parts or in sterile pollen, and functional male sterility, where the male flower parts are incapable of causing pollination. The compounds (I) used according to the invention also cause other growth regulating effects, such as, for example, control of flowering, control of fruit formation and inhibition of seed formation in non-cereal species and other related growth regulating effects.

When the composition is used as a hybridizing agent, they are applied in an amount sufficient to give the desired effect on the plant without causing any undesirable or phytotoxic effect. The compositions are usually applied to the crop to be treated in an amount of from 0.035 to 22.42 kg per hectare and preferably from 0.14 to 11.21 kg per hectare. The amount applied varies depending on the crop being treated, the compound used for the treatment and similar factors.

To obtain hybrid seeds, the following procedure was usually used. The two "parent" plants to be crossed are planted in alternating rows. The female parent is treated with a compound of the invention. The thus formed male sterile female parent is pollinated with pollen from the other, male fertile, male parent, and the seeds formed by the female parent will be hybrid seeds, which can then be harvested in a conventional manner.

A preferred way of applying a composition according to the invention as a chemical hybridizing agent is by foliar application. When this method is used, selective male sterility is effectively achieved when the compound is applied between flowering initiation and meiosis. The composition according to the invention can also be used for seed treatment by immersing the seeds in a liquid preparation containing the active compound or by coating the seeds with the composition. In seed treatment applications, the compounds of the invention are usually applied in an amount of from about 1/4 to 10 kg per hundred kg of seeds. The compounds used according to the invention are also effective when applied to the soil or to the water surface in rice crops.

The compounds (I) used according to the invention can be used as hybridizing agents together, for example in admixture, with other growth regulating agents, such as auxins, gibberellins, ethylene releasing agents such as ethylene, pyridones, cytokinins, maleic acid hydrazide, succinic acid 2,2-dimethylhydrazide, choline and its saline. , (2-chloroethyl) trimethylammonium chloride, triiodobenzoic acid, tributyl-2,4-dichlorobenzylphosphonium chloride, polymeric N-vinyl-2-oxazolidinones, tri (dimethylaminoethyl) phosphate and its salts and N-dimethylamino-1,2,3, 6-Tetrahydrophthalamic acid and its salts. Under certain conditions, the compounds used according to the invention may advantageously be included together with agricultural pesticides, such as herbicides, fungicides, insecticides and plant bactericides.

One or more of the compounds (I) used according to the invention can be applied to the growth medium or to the plants to be treated, as a component of a growth regulating composition or preparation, which also comprises a carrier which can be contracted in an agricultural context, such as e.g. carriers that are tolerable in agricultural contexts but pharmaceutically unacceptable. "Agricultural carrier" means any substance which can be used to dissolve, disperse or disperse a compound in the composition without impairing the effectiveness of the compound and which in itself has no appreciable adverse effect on the soil, the equipment, the crop or the agronomic environment.The growth regulating compositions may be either solid or liquid preparations or solutions.The compounds may be prepared, for example, in the form of wettable powders, emulsifiable concentrates, dusts, granules, aerosols or liquid emulsion concentrates.In such preparations the compound is extended with a liquid or solid carrier, and, if desired, suitable surfactants are incorporated 469 585 14 In the formulations, the concentration of the active ingredient in the respective formulation may be from 99.99% by weight to 0.001% by weight.

It is generally desirable, especially in foliar application, to incorporate adjuvants, such as wetting agents, dispersants, dispersants, tackifiers, binders and the like, in accordance with agricultural practice. Examples of additives commonly used in this technology can be found in the publication "Detergents and Emulsifiers Annual" published by John W.

McCutcheon Inc.

The compounds (I) used according to the invention may be dissolved in any suitable solvent. Examples of solvents useful in the practice of the present invention are water, alcohols, ketones, aromatic hydrocarbons, halogenated hydrocarbons, dimethylformamide, dioxane and dimethylsulfoxide. Mixtures of these solvents can also be used. The concentration of the solution may vary from about 2% to about 98% by weight, with the preferred range being from about 20% to about 75%.

For the preparation of emulsifiable concentrates, the compound may be dissolved in organic solvents such as benzene, toluene, xylene, methylated naphthalene, corn oil, tall oil, o-dichlorobenzene, isophorone, cyclohexanone or methyl oleate, or in mixtures of these solvents, together with an emulsifier or surfactant. which allows dispersion in water. Suitable emulsifiers include, for example, ethylene oxide derivatives of alkylphenols or long chain alcohols, mercaptans, carboxylic acids and reactive amines and partially esterified polyhydric alcohols. Solvent-soluble sulfates or sulfonates, such as alkaline earth salts or amino salts of alkylbenzene sulfonates and fatty alcohol sodium sulfates, having surfactant properties can be used as emulsifiers either alone or together with an ethylene oxide reaction product.

Liquid emulsion concentrates are prepared in the same manner as the emulsifiable concentrates and comprise, in addition to the above components, water and a stabilizing agent, such as a water-soluble cellulose derivative or a water-soluble salt of a polyacrylic acid. The concentration of the active ingredient in emulsifiable concentrates is usually from about 10% to 60% by weight, and in liquid emulsion concentrates it is usually from about 10% to 60% by weight or even as high as 75% by weight. - percent.

Wettable powders suitable for spraying can be prepared by mixing the active compound with a finely divided solid, such as clays, inorganic silicates and carbonates and silica, and by incorporating wetting agents, adhesives and / or dispersants into such mixtures. The concentration of active ingredients in such a wettable powder is usually in the range of from about 20% to 98% by weight, preferably from about 40% to 75%. A dispersant may generally comprise from about 0.5% to about 3% by weight of the wettable powder, and a wetting agent may usually comprise from about 0.1% to about 5% by weight of the composition.

Dust agents can be prepared by mixing the active compounds with finely divided inert solids, which may be of an organic or inorganic nature. Materials useful for this purpose include botanical flour, silica, silicates, carbonates and clays. A suitable method for producing a dust involves diluting a wettable powder with a finely divided carrier. Dust concentrate containing from about 20% to 80% of the active ingredient is usually prepared and then diluted to about 1% to 10% by weight as a concentration in use.

Granular preparations can be prepared by impregnating a solid, such as granular bleaching earth, vermiculite, ground corn cobs, pods, including bran or other pods or similar materials. A solution of one or more of the compounds in a volatile organic solvent may be sprayed or mixed with the granular solid, whereupon the solvent is removed by evaporation. The granular material may be of any suitable size, with the preferred size range being from 16 to 60 mesh (U.S. Standard Sieve Series). The active compound usually constitutes from about 2 to 15% by weight of the granular preparation.

Salts of the compounds (I) used according to the invention can be prepared and applied in the form of aqueous solutions. The salts usually make up from about 0.05 to about 50% by weight, preferably from about 0.1 to 10%, of the solution. These compositions may also be further diluted with water, if desired, before actual use. In some uses, the activity of these compositions can be improved by incorporating into the compositions an additive such as glycerol, methyl ethylcellulose, hydroxyethylcellulose, polyoxyethylene sorbitan monooleate, polypropylene glycol, polyacrylic acid, polyethylene sodium maleate or polyethylene oxide.

The additive usually constitutes from about 0.1 to about 5% by weight, preferably from about 0.5 to about 2%, of the composition.

Such compositions may also optionally contain an agronomically acceptable surfactant.

The compounds (I) used according to the invention can be applied in the form of sprays by conventionally used methods, such as conventional hydraulic spray, air spray and dusting agent.

For low volume applications, a solution of the compound is usually used. The dilution and application volume usually depend on such factors as the type of equipment used, the method of application, the area to be treated and the type and stage of development of the crop being treated.

The following examples illustrate the growth regulating activity of the compounds (I) used according to the invention but are not intended to limit the invention in any way. 469 585, 17 Example 1 Chemical Hybridization Activity The following procedures were used to evaluate the activity of the compounds (I) used in the invention to achieve male sterility in cereals.

A bait brush variety (Fielder) and a bait brush free variety (Mayo-64) of spring wheat are planted in an amount of 6 to 8 seeds per 15.25 cm pot containing a sterile medium of 3 parts by weight of soil and one part by weight of humus. . The plants are allowed to grow under short-day conditions (9 hours) during the first 4 weeks in order for them to achieve good vegetative growth before flowering begins. The plants are then transferred to long-term conditions (16 hours), which conditions are achieved by means of high-intensity lamps in greenhouses.

The plants are fertilized 2, 4 and 8 weeks after planting with a water-soluble fertilizer (nitrogen-phosphorus-potassium = 16% - 25% -16%) in an amount of 1.3 ml per liter of water and are often sprayed with a suitable insecticide, such as the one marketed under the "Isotox" brand, for the control of aphids and treated with sulfur dust to prevent the formation of mold.

The test compounds are applied to the leaves of the female plants provided with bait bristles, when these plants reach the stage of development with sharp leaves (step 8 on the Feeke scale). All compounds are applied in a carrier volume of 468 l / ha containing a surfactant, such as that marketed under the trademark "Triton X-100", in an amount of 0.3 g / l.

After the ear has developed but before antesis, 4 to 6 ears per pot are placed in bags to prevent crossing. At the first signs of flower opening, two ears per pot are cross-pollinated, using the experimental method, with the male plant free from bait bristles. As soon as the seeds become clearly visible, the axle length is measured and the number of seeds per axle is counted for both the axle in bags and the crossed axes. Male sterility can then be calculated as the percentage inhibition of seeds obtained in the bagged axes of the treated plants, and the female fertility of the crossed axes can be calculated as a percentage of control or comparison seeds. After ripening, seeds are planted on crossed ears to determine percentage hybridization. The "experimental method" mentioned above involves bringing the axes to be cross-pollinated close to each other or in contact with each other and enclosing the axle in a transparent bag.

The percentage sterility, the percentage fertility and the percentage inhibition of the shoulder length are calculated using the following formulas: See - St a)% sterility = SX 100 c SC = seeds / small ears in ears of control plants placed in bags St = seeds / small ears in ears of treated plants placed in bags F b)% fertility = Ft X 1000 c Ft = seeds / small ears in experimentally crossed ears of treated plants Fc = seeds / small ears in ears of control plants not placed in bags e) 96 axial inhibition = _H @ _'_ É1 _; _ x 1oo H c Hc = shoulder length of control plants Ht = shoulder length of treated plants.

Table III summarizes typical results obtained in evaluating compounds of the invention. A dash indicates that no determination of the value was made. _2L____ 3F 3? 4-cH3,3-c1 4-cH3,3_c1 4-1 _ 4-I 4-Br 4-Br _ 4-NO2 4-CH3 4-CH3 32 I: ICC ä! 3231 IIS 19 Na Na Na Na Na Na Na Na I 469 585 TABLE III eametocidal activity X% sterility (via kg / na) 8.96 4.48 2.24 1.12 o.se 0.28 -__ 100 94 72 46+ I 1+ 74 83 __- 100 100 100 100 81 16 9 10 14 10 --- 0 14 2 13 6 --- --- ¶1o0 100 100 99 --- 10o 100 100 100 100 97+ az ___ 100 100 100 100 --- 100 100 100 100 1oo + 98+ _ as 73 __- 100 97 100 96 --- 1oo 100 .100 100 97+ 99+ 90 ao 9 19 9 16 s 16 a __? 73 41 _ 100 98+ 92+ se 12 --- 1o0 100 469 585 20 TABELL_; II (cont.) 4. É Sterility fl at kg¿ha2 x 3_ 5_ 8.96 4.48 2.24 1.12 -0.56 0.29 4_c1, H 'H 33 15 _-- -__ -__ -__ (naphthyl) q_c1 H Ha 0- 5 4 4 9 -__ (naphthyl) 4 -OCH3 HH »100 94 --- ___ --- --- 4_0cH3 H Ha 100 100 * 99 * 03 * 43 * __- 100 99 100 _100 4-? HH 100 --- 4_F H Na 100 100 100 100 Ä 95 66 * se 3,4_dic1 HH 100 ;; _ __- _-- _-- _-, 3,4_d1c1 H Na 100 93 92 16 --- - - 4-c1 HH _100 100 96 --- --- --- 4-c1 H Na 100 100 100 * 100 * 100 * 100 * 45 34 90 72 3_c1 H Na He --_ -__ __- --- --- 3-c1 H Na 100 100 74 64 * 94 --- 73 HHH 75 ___ HH Na 100 »100 100 100 97 * 40 * 90 97 4_cH3 Br H ___ 6 '2 10 7 3 __- 4-CH3 Br Na 9 3 --- 8 7 --- 4-F Br H 4-? sr ua 100 100 100 100 * 04 * 15 ss 73 4-sr ar H --- --- --- 02 48 32- 4-Br Br Na --- H Hr .H ___ H sr Ha -__ _- - _-- 100 se 10-- '4_Br ~ c1 Na ___ _ 100 _ 100 92 ss --- 4-Cl H CH3 ++ --- ++ --- 100 -Å- "° 4_c1 - H c H - 100 ___ 100 ___ 100 --- ° - '°? 5 469 585 21 + results of several performed results x 35 at 0.14 kg / ha xx 0 at 0.14 kg / ha xxx 96 at 0.14 kg / ha xxxx 99 at 0.14 kg / ha ++ development of ax inhibited at 2.24 and 8.96 kg / ha The invention is particularly useful in improving the commercial value of seeds for the production of cereals by hybridization (1) which means that in a mechanical spreading device a hybridization composition containing a compound of formula I and a carrier compatible with it for agriculture is used, (2) that the mechanical spreading device is used to in the form of a dusting agent or a liquid spray applying the hybridization composition to the leaves of a male and female cereal plant prior to meiosis, wherein by male sterility, (3) by pollinating the "parent" plant thus treated with pollen from a male plant of the cereal, (4) by allowing the pollinated plant to mature until seeds are formed and (5) by that the ripe seeds are harvested.

Claims (3)

469 585 22 Patent claims Composition for controlling growth in cereal plants by producing selective male sterility, characterized in that it contains a carrier which is compatible in the agricultural context and as active ingredient a compound of formula (I) in which R1 is carboxy, or a salt which is tolerable in agriculture. , or alkoxycarbonyl having up to 12 carbon atoms in the alkoxy moiety, R 2 is a phenyl or substituted phenyl having up to 3 substituents which collectively, in the case of carbonaceous substituent (s), have from 0 to 6 carbon atoms in total, wherein the substituent or substituents is selected from (1) alkyl, (2) C 4 H 4 = forming a naphthyl group, (3) alkoxy, (4) halogen, (5) nitro, (6) trifluoromethyl, (7) alkanoyloxy and (8) alkyl- ten, 123 is (C 1 -C 4 alkyl and R 4 is hydrogen, (C 1 -C 4) alkyl or halogen. Composition according to Claim 1, characterized in that it also contains an agricultural auxiliary, such as a wetting agent, dispersant, tackifier or adhesive. Composition according to Claim 1 or 2, characterized in that R 1 is carboxy or an alkali metal salt thereof, R 2 is 4-chlorophenyl, R 3 is methyl and R 4 is hydrogen. 7 ny '