DE814806C - Plant physiologically active agents - Google Patents

Description

Plant physiologically active agents It has been found that salicylic acid acylated on the oxygen or its ring-substituted derivatives, as such or in the form of their salts and esters, ie compounds of the general formula where R is an aliphatic, cycloaliphatic, araliphatic, aromatic radical, optionally further substituted via heteroatoms or atom groups, A indicates one or more substitutions of any kind and X is hydrogen, one of those symbolized by R. Residues or any organic or inorganic base bound in a salt-like manner denotes substances which have a strongly damaging influence on the growing plant and a strongly inhibitory influence on the germination capacity of seeds and root crops.

Compounds of the type described are known and in large numbers their preparation has been described repeatedly. Usually one goes with it from salicylic acid or its core substitution products and treated these with acylating agents, such as. B. with the anhydrides or halides more organic Carboxylic acids. Two are equally effective in obtaining the esters Ways possible, insofar as one once the acylated salicylic acids, either directly or via their halides in a known manner, esterifying with organic oxy compounds can or by forming the salicvic acid esters and subsequently acylating them. As has now been found, numerous representatives of these classes of compounds have a more or less pronounced plant physiological effect, both the finished developed plant as well as the germinating seed or the germinable root crop versus, which in numerous cases is powerful enough to be used successfully to be approved as a weed control or germ control agent for stored root crops.

Compounds used in accordance with the present invention can, are for example: acetylsalicylic acid, acetyl-3-chlorosalicylic acid, Acetyl-5-chlorosalicylic acid, acetyl-3, 5-dichlorosalicylic acid, acetyl-5 = bromosalicylic acid, Acetyl-5-iodosalicylic acid, acetyl-3-nitrosalicylic acid, acetyl-5-nitrosalicylic acid, . Acetyl-5-chloro-3-nitrosalicylic acid, acetyl-3-bromo-5-nitrosalicylic acid, acetyl-3, 5-dinitrosalicylic acid and others. m., also n-propionylsalicylic acid, chloroacetYl-3-chlorosalicylic acid, Trichloroacetyl-5-chlorosalicylic acid, bromoacetyl-3, 5-dichlorosalicylic acid, benzoyl-3-chlorosalicylic acid, (3-chlorobenzoyl) salicylic acid, phenylacetyl-5-chlorosalicylic acid, salicoylsalicylic acid, (Phenoxyacetyl) salicylic acid, (4'-chlorophenoxyacetyl) -3-chlorosalicylic acid, (2,4-dichlorophenoxyacetyl) salicylic acid, 4'-chloro-2-cresoxyacetyl-5-chlorosalicylic acid, succinyldisalicylic acid, adipoyldi-5-chlorosalicylic acid, 2-Acetoxynaphthoic acid-3, i-chloro-2-acetoxynaphthoic acid-3 and others. .m. As an ester of The aforementioned acids are suitable, for example: the methyl, ethyl, i-propyl, n-butyl, n-hexyl, n-dodecyl, benzyl, chloroethyl, oxethyl-naphthyl-i-methyl, Tetrahydronaphthyl-2-methyl-, Jlethoxyäthyl-, Pheny läthyl-, Phenoxyäthylester and those with aromatic radicals such as phenyl, 4-cresyl, 4-phenylphenyl, 4-benzylphenyl, 4-phenoxyphenyl-, 4-chlorophenyl-, 4-nitro-2-cresyl-, 2, 4-dichlorophenyl-, 4-chloro-, 2-cresyl- and i-naphthyl ester, among others. m. and finally also such polyhydric alcohols or Phenols such as B. Glycol, i, 4-butylene glycol, i, 6-hexanediol, diethylene glycol, hydroquinone, Resorcinol et al. m.

Should the acylated. Salicylic acids in the form of their water-soluble ones Salts are used, then it should be noted that when using strong alkalis In the case of longer storage times, intramolecular saponification is possible is why it is advisable to do this primarily with organic bases, such as z. B. diethanolamine, triethanolamine, dimethylamine, cyclohexylamine, morpholine, pyridine, To work quinoline, etc., the application in practice is generally the same the usual methods for this and is based on the intended purpose. To the One can, for example, prevent premature germination of stored root crops proceed in such a way that the active ingredient with 5 to ioo times the amount of a inert carrier, such as. B. talc, kaolin or rock flour, finely ground and carefully dust the crop to be protected with it. The application rates can fluctuate within wide limits depending on the storage conditions. and lie generally between 10 and 50 g per 100 kg of stored goods. Experience shows point out that for the production of antimicrobial storage protection agents water-insoluble esters seem to be somewhat more suitable than the free acylated ones Salicylic acids, while for the manufacture of weed killers, which im In the open air, mainly the plants that have already developed should act on them, mostly preference is given to the water-soluble salts of the latter.

Compared to plants, the new active ingredients show considerable differences in effectiveness in the sense that leafy plants are generally considerably more susceptible than grasses, so that a selective control of weeds in cereals and grassland is easy Kind is possible. One can proceed in such a way that the accrued Seeds or the green areas are sprayed with dilute aqueous solutions of the active ingredients or dusted with dry preparations. The required application rates vary depending on the weather and the type and degree of weed growth.

In the presence of organic solvents, such as. B. benzene, tetralin, Decalin, anthracene oil and others. m., the mentioned effectiveness sub-. divorced almost completely and Gramineae then turn out to be extremely susceptible. Taking advantage of this fact, it is possible to get the new active ingredients there too to use with success where the task is to remove any vegetation to eliminate, e.g. B. on courtyards, paths, sports fields, track systems, etc., that is where up to now only large amounts of sodium chlorate or arsenic-containing, highly toxic agents came to the goal. The application rates are also in these cases relatively small and move when properly prepared and used correctly between 10 and 15 kg / ha.

The new active ingredients, especially the water-soluble salts, are to be understood in their mode of action as plant contact poisons, those through direct contact come into effect with the parts of the plant, especially the leaves. they are no growth substances, such as B. 2, 4-dichlorophenoxyacetic acid or 4-chloro-2-cresoxyacetic acid, which damage the plant in the event of an overdose and are also absorbed through the soil and which of late especially in America and England on a large scale used for weed control purposes. Opposite these have the new Means the advantage that the treated area is agricultural after a short time can be used as required without fear of damage to the overseeding. This also applies to those areas where the means in the manner described above were used together with organic solvents as total destroyers, while, as is well known, the use of chlorate is sustainable, sometimes for years permanent soil contamination the result is: Another, by no means insignificant Advantage against; about chlorates is that the after successful Treatment of withered weed areas do not pose an increased risk of fire.

Examples i. In a 100 square meter mixed stock of at the same time Sown oats and mustard were used at the time when the weeds the second leaf that oats had developed the third leaf, a spray treatment with i2 l of an i 7eigen aqueous solution of the diethanol salt of acetyl-5-chlorosalicylic acid (F. of the acid = 16 to 17 °). While all the mustard was dying, the oat plants remained completely undamaged.

2. Heavily weed parts of a sports area were given a aqueous emulsion, consisting of 10 parts of tetralin, 1 part of the diethanolamine salt : lcetyl-3, 5-dichlorosalicylic acid (F. of acid 138 to i39 '), 0.5 parts of emulsifier and 88.5 parts of water sprayed in such a way that 100 g of the same (corresponding to i g of active ingredient) reached the square meter, whereby a destruction of the vegetation achieved became.

3. 500 kg of potatoes stored in autumn were carefully dusted with a mixture of 50 g acetylsalicylic acid-2,4-dichlorophenyl ester (m.p. 99.5 °) and 95o g of talc. The potatoes were, in contrast to untreated, Stored under the same conditions, fresh and practically without germs.

Claims (2)

PATENT CLAIM: i. Agents with a physiological effect on plants, in particular those for the selective and total destruction of weeds and those for preventing premature germination of stored root crops, characterized by a content of salicylic acid derivatives of the general formula wherein (R) represents an aliphatic, cycloaliphatic, araliphatic, aromatic radical, optionally further substituted via heteroatoms or atom groups, (A) indicates one or more substituents and (X) denotes hydrogen, one of the radicals symbolized by (R) or any indicates organic or inorganic base bound in a salt-like manner. 2. Means according to claim i, characterized characterized in that, in addition to the active ingredients mentioned, organic fat-dissolving substances and / or further agents influencing plant growth are contained therein.