CS203025B2 - Herbicide - Google Patents

Abstract

A synergistic herbicidal agent comprises a compound <IMAGE> wherein X is chlorine or bromine, Y is hydrogen if X is Cl or is chlorine if X is Br, and Z is (C1-C4)-alkyl, and a compound <IMAGE> wherein R is bromine or iodine and R1 is hydrogen, alkali metal, ammonium, formyl or alkanoyl having up to 8 carbon atoms. The invention also provides the use of such agents for the selective control of mono- and di- cotyledonous weeds in cereals.

Description

The present invention relates to a herbicidal composition comprising as active ingredient a combination of active ingredients.

It is already known that isobutyl 2-f (4'-chlorophenoxy) phenoxy] propionic acid (II) isobutyl ester is effective against a number of grassy weeds, for example, fox-tail, in pre-emergence and post-emergence application (DOS 2,223,894). Similar data are given for 2-C4-C2'-chloro-4'-bromo-phenoxy) -phenoxy] -propionic acid methyl ester (I) for deaf oats, common foxtail and certain types of millet (DOS 2 601 5413). The selectivity, i.e. the harmlessness of these compounds to certain cereal cultures, is emphasized.

Furthermore, it is known that 3,5-dihalgth-4-heterocyclolithrillol, for example, Ioxynil (3,5-diiodo-4-dihydro-4-dihydro-3,5-dihydro-3,5-dihydro-3,5-dihydro-3,5-dihydro-3,5-dihydro-4'-diol) is used as means for combating weeds in cereal crops.

In the usual application, the effect of said substances is good, but often does not affect all weeds in cereals. Thus, the efficacy of compounds (I) and (II) is narrowly limited to grass weed species, while the broad-leaved weeds remain either undamaged at all or are only severely damaged. Conversely, Ioxynni and bromooxyel act very well against a number of broadleaf weeds, such as camomile or 14beda, but they are ineffective against grassy weeds.

It has now surprisingly been found in experiments with the combinations mentioned above that compounds I or II with Ioxynil or have more than a total, i.e. synergistic, effect when applied against broadleaf weeds in cereals.

The invention therefore provides herbicidally active combinations which are characterized by the content of the compound of formula (A)

Y «3

CH-COOZ (A) wherein

X is chlorine or bromine,

Y is hydrogen if X = Cl or chlorine if X = Br and

A C 1 -C 4 alkyl group is used in combination with a compound of formula B

R in which

R is bromo or iodo,

R 1 is hydrogen, an alkali metal cation or an ammonium cation or is an alkanoyl group having 1 to 8 carbon atoms as active ingredient, the ratio of components A: B in the mixture being from 1: 0.05 to 1: 5.

In particular, the compounds of formula (A) are:

Even meethyester 2- [4- ⁽² -chlt) r 4 ^/ bbromfnюxy) feюxyJ-prt) piontvé acids and,

II 2-C4- (4'-chloro-triphenyl) -phentoxy] -propionic acid isobutyl ester.

In particular, the compounds of formula B are:

III 3,5-dihydro-4-hydroxy-benzonitrile (Ioxynil), its sodium, potassium or ammonium salt or its octanoate and

IV 3,5-diirtyl-4-) dihydroxybenzoic acid (Β χ Ι Ι), or a sodium salt thereof, or an oleate thereof.

The synergistic effect of the combinations according to the invention is particularly pronounced when used against broadleaf weeds. Thus, the addition of a compound of formula A can significantly reduce the required conneenation of the compound of formula B to successfully control dicotyledonous weeds.

The combinations according to the invention are particularly suitable for the control of annual weeds in crops of winter and spring cereals, in particular beech, chamomile, bedstraw, blackgrass and deaf oats. The ratio of components A: B in the mixture may co-vary in a ratio between 1: 0.05 and 1: 5. Preferably, the ratio of components A: B varies between 1: 0.1 and 1: 1. The total applied quantity of components A + B required is of the order of 0.5 to 2 kg / ha.

The compositions of the present invention may be in the form of mixed powders, emulsifiable conicrates or dusts, and the comprehensive excipients commonly used in such compositions, such as mixtures, adhesives, adhesives, disinfectants. Ethers, solid or liquid inert substances, as well as grinding or grinding aids.

The carrier materials used may be: substances such as aluminum silicates, clays, kaolin, chalks, siliceous chalks, bridges, silica or hydrated silicic acids or preparations of these minerals with special additives such as chalk containing sodium stearic acid. All suitable and suitable organic solvents, such as toluene, xylene, diacetealkthot, istftrte, gasoline, paraffinic oils, dioxane, dimethylformamide, dimethylisulfide, ethyl acetate, butyl acetate, chlorobenzene and the like, can be used as carriers for liquid preparations.

Cellulose-based products or alcohols may be used as adhesives.

Suitable suitable emulsifiers are, for example, alkylated alkylenes, aryl or longkylenesulphonic acid salts, benzenesulphonic acid salts or bals.

Suitable dispersants are the resins resulting from the manufacture of the pulp (sulphate waste liquor salts), the ejphthalenesulphonic acid salt and, if appropriate, the hydrated silicic acid or also the silica.

Suitable inorganic or organic salts such as sodium sulfate, ammonium sulfate, sodium carbonate, sodium bicarbonate, sodium thiosulfate, sodium stitch acid, sodium acetate may be used as a grinding aid.

The active compound content of these compositions is generally between 2 and 85%. Prior to application, the compositions are diluted by addition of a suitable solvent or diluent (mostly water) to the desired application.

Simple means suitable for testing the effect can be obtained, for example, according to the following regulations:

EXAMPLE 1 Axis Compounds I (calculated as pure active ingredient), parts by weight of Compound IV in the form of octanoate (calculated as pure active ingredient); containing 56% of compound IV as free phenol (corresponding to 9 parts by weight),

15.1% of the fatty acid polyglycol ether family

10.0% cyclohexanone lotion,

29.0 hulotnetSnow part of xylene,

6.5 parts by weight of a mixture of dodecylbenzenesulphonic acid calcium salt and alkylene-polyglycol ether; and

4.5 parts by weight of the polysglycol.

Example 2.

22.0% by weight of part I (calculated on the pure active substance).

16.0 parts by weight of the compound IV as octanode (calculated on the pure active substance);

containing 56% of compound IV as free phenol (corresponding to 9 parts by weight),.

10.0} of the inheritance of cyclohexanone,

27,9] 'ulottic inheritance of xylene,

11.0 µl of a portion of polyglycol ether of lithium oil and

9.0 parts of calcium blend teiddedleyreerzsnsuefonové kesnle ra aallfelfinytpo “^ 1ι ^ 1 (1 ^ ™).

The synergistic effect of the active compound combinations results from the following examples. While the individual active substances exhibit gaps in the herbicidal action, οε ^ ί ^ ιηϊ ^ ηβ ^ a broad weed control that exceeds the simple sum of the effects of the individual components.

A synergistic effect always occurs when the effect of the active compound combinations is greater than the effect of the individual active compounds. The expected effect for a given combination of two herbicides (cf. Colby, SR, Calculation of synergistic and antagonistic responses of herbicide combinations, Weeds 1 May 1967, pp. 20-22) can be calculated as follows: If X =% damage caused by herbicide A when applied quantity x kg / ha and Y =% damage caused by herbicide В at application rate у kg / ha, then the expected damage caused by the combination A + В at application rate (x + y) kg / ha is calculated from the formula

100 ALIGN!

If the actual damage is greater than E, then the effect of the combination is more than the sum, i.e., it exhibits a synergistic effect as demonstrated in the following examples.

Example 3

In a greenhouse experiment, different weeds are treated after emergence with compounds I, III or IV as well as combinations I + III and I + IV. The result of the experiment is shown in the following table. In this case, the effect is generally reported in% of damage, and in the case of combinations, this effect is differentiated between the calculated effect according to the above formula (in parentheses) and then on the effect actually found.

Table for example 3:

treatment kg / ha of hydroxybenzonitrile (III or IV)

rate in kg / ha 0 0,075 0.15 0.3 0.6 and) goosefoot white Chenopodium album III 0 - 20 May - 25 - 54 - 94 0.72 I + III 9 (27.2) 88 (31,75) 100 ALIGN! (58,14) 100 ALIGN! (94,54) 100 ALIGN! 0.54 II + III 5 (24) 60 (28,75) 75 (56.3) 82 (94.3). 99 IV 0 - 56 - 98 - 100 ALIGN! - 100 ALIGN! 0.72 I + IV 9 (59,96) 80 (98,18) 98 (100) 100 ALIGN! (100) 100 ALIGN! 0.54 II + IV 5 (58.2) 85 (98.1) 100 ALIGN! (100) 100 ALIGN! (100) 100 ALIGN! (b) Chamomile (Matricaria chamomilla) III 0 - 20 May - 40 - 60 - 85 0.72 I + III 5 (24) 45 (43) 70 (62) 75 (85,75) 97 IV 0 - 25 - 50 - 75 - 90 0.72 I + IV 5 (28,75) 50 (52.5) 75 (76,25) 90 (90.5) 100 ALIGN! C) Galium aparine III 0 - 13 - 20 May - 33 - 50 0.72 I + III 1 1 (22,57) 30 (28.8) 40 (40,37) 50 (55.5) 80 (d) Dried oats (Avena fatua) III 0 - - - - 9 0.09 I + III 52 - - - (56,32) 70 IV 0 - - - - 10 0.09 I + IV 52 - - - (56.8) 72

By comparing the found and calculated effects, a synergistic effect can be clearly identified.

Example 4

In a greenhouse tolerance test on spring wheat and spring barley, it was found that treatment with the individual active substances as well as treatment with combinations of these substances did not damage said crop plants.

kg / ha active compound spring wheat spring barley 0.72 AND 0 0 0.54 11 0 0 0.6 III 0 0 0.6 IV 0 0 I + III 0 0 I + IV 0 0 II + III 0 0 II + IV 0 0

SUBJECT OF THE INVENTION

Claims (3)

A pharmaceutical composition comprising, as active ingredient, a compound of formula (A): X is chlorine or bromine, Y is hydrogen when X = Cl, or is chlorine when X = a Z represents a C 1 -C 4 alkyl group, in combination with a compound of formula B R (B) wherein R is bromo or iodo and R 1 represents hydrogen, an alkali metal cation or an ammonium cation or a C 1 -C 8 alkanoyl group, the ratio of components A: B in the mixture being from 1: 0.05 to 1: 5. 2. A composition according to claim 1, wherein the active ingredient is 2- [4- (2'-chloro-4'-bromophenoxy) phenoxy] propionic acid methyl ester (I) or 2-E4- (4'-chloropheno) isobutyl ester. (y) phenoxy] propionic acid (II) as component A, in combination with 3 ₁ 5 'dijod-4'hydroxybenzooatrieem or its sodium, potassium or ammonium salt or its octanoate (III), or 3,5-dibromo-4-hУ ^dг oKybbnaooatгilem or its sodium salt, or its octanoate (IV) as the component B. 3. A composition according to claim 1, wherein the ratio of components A: B in the mixture is from 1: 0.1 to 1: 1.