CS270564B2 - Bactericide - Google Patents

Abstract

Bactericidal compositions contain, as active substance, a derivative of the formula <IMAGE> where R is H or (C1-C4)alkyl, M radicals are identical or different and are H, alkali metal, alkaline earth metal or Al, n is the valence of M, and can be used in agriculture and horticulture.

Description

(57) A bactericidal composition comprising, as an active ingredient, at least one compound of the formula I, wherein R is hydroxyl, C 1-4 alkyl or -alkoxy, M is hydrogen but only R is hydroxyl, or an alkali metal, alkaline earth metal or aluminum atom and n is an integer having a value of 1 to 3, provided that if n is greater than 1, the residues M may be the same or different. The disclosed composition is suitable for combating bacterial diseases of plants.

CS 270> 64 B2

27 Mar: 0 564 Italy (11) (13) 82 (51) Int. Cl? AND Ol N 57/20 AND Ol N 57/12

H (R - P - O ') _n M ⁿ * (I) it π

CS 270 564 02

The present invention relates to novel bactericidal compositions based on phosphoric acid derivatives as well as to methods of treating plants with these derivatives in order to combat bacterial diseases.

It is known to use phosphonic acid, its salts and salts of some of its monoesters, namely aluminum tris-O-ethylphosphonate, as agents against fungal diseases of plants, but the bactericidal properties of these compounds have not been described so far.

BACKGROUND OF THE INVENTION The present invention relates to bactericidal compositions comprising as active ingredient a compound of formula (I)

H (Г - P - 0 ”) _ M ⁿ * (I)

Kterém n in which

R represents a hydroxyl group, a C1-C4 alkyl group or a C1-C4 alkoxy group,

M represents a hydrogen atom (only when R is a hydroxyl group), an alkali metal atom, an alkaline earth metal atom or an aluminum atom and n is an integer of 1 to 3, provided that if n is greater than 1, individual residues in the meaning of M symbols different meanings.

Of the compounds of formula I, the monosodium or potassium and disodium or potassium salts of the above-mentioned phosphonic acids as well as the sodium, potassium, calcium and aluminum salts of ethylphosphonic acid are preferred.

The invention also provides a method for combating bacterial diseases of plants using the above derivatives.

The bactericidal properties of the latter derivatives and compositions containing them are illustrated by the following examples.

He did

Tomato plants, divided into three pots of 15 cm diameter, are contaminated with Xanthomonas campestris and incubated for 24 hours at ° 28 ° C in polyethylene bags. The plants are then sprayed with an aqueous dispersion of a commercial wettable powder (ALIETTE 80 WP) containing 80 wt. aluminum tris-O-ethylphosphonate (fosethyl-Al).

The effectiveness of the test preparation is evaluated by selecting the most infested leaf from each plant and counting the number of spots.

It was found that while on control plants (contaminated but untreated) 281 spots on the leaves were counted, only 45 spots were counted on plants treated with fosethyl-Al at a dose of 2.2 kg of active substance per hectare. The performance of the above formulation is comparable to that of a commercial standard medium based on hydroxide.

This test demonstrates the excellent bactericidal properties of the compounds of the invention.

Example 2,

Efficacy test for phytopathogenic bacteria in vitro

The activity of the compound of the invention was tested on the following phytopathogenic bacteria:

CS 270 564 B2

Xanthomonas Xanthomonas Xanthomonas Xanthomonas campestris campestris campestris

Erwinia amylovora

Erwinia carotovora atroseptica

Erwinia carotovora carotovora

Pseudomonas syringae persicae Pseudomonas syringae lachrymans Pseudomonas syringae tomato Corynebacterium michiganense

Each test is performed as follows:

Oo Petri dishes sterilized in an autoclave at 120 ° C are placed in 20 ml portions on each dish with a refrigerated culture medium (Sabouraud) containing 10 g / liter peptone, 20 g / liter glucose and 15 g / liter agar. During the filling of the dishes, an aqueous solution of fosethyl-Al preparation is injected into the subcooled medium in such a quantity as to obtain the desired concentration of the active substance in the resulting medium.

Controls are the same Petri dishes in which the same amount of culture medium has been introduced but without the addition of the active ingredient.

After 24 or 48 hours, each dish is inoculated with an aqueous suspension of bacteria, obtained by 100-fold dilution of the basic suspension of optical density 1.

The plates are kept at 22 ° C for 2 to 10 days (depending on the test bacterium) and then the growth of the bacteria in the plates containing the test compound is compared to that of the control plates.

It has been found that the application of the above-mentioned active ingredient at a dose of 1000 ppm results in complete inhibition (100%) of all test bacteria.

Example 3

The procedure is analogous to that of Example 2 except that phosphorous acid at a dose of 685 ppm is used as the active ingredient.

It was found that the application of this active ingredient at the above dose resulted in complete inhibition (100%) of all the test bacteria listed in Example 2.

Example 4

The procedure is analogous to that of Example 2, except that sodium dihydrogen phosphate at a dose of 868 ppm is used as the active ingredient. '

It has been found that when the active ingredient is administered at the above dose, 100% of the following test bacteria are completely inhibited:

Erwinia carotovora atroseptica

Erwinia carotovora carotovora

Erwinia chrysanthemi

Pnnudomonns nyrlnano lechrymnna

Corynebacterium michiganense

Accordingly, the compositions of the invention may be used to combat bacterial diseases of plants, in particular diseases caused by the following organisms:

Xanthomonas sp., In particular Xanthomonas campestris pv, for example Xanthomonas campestris campestris, Xanthomonas campestris citri, Xanthomonas campestris malvacearum, Xanthomonas

CS 270 564 82 campestris oryzae or Xanthomonas gerani,

Erwinia sp., In particular Erwinia amylovora, Erwinia carotovora atroseptica, Erwinia carotovora carotovora or Erwinia chrysanthemi;

Pseudomonas sp., In particular Pseudomonas syringae pv, for example Pseudomonas syringae morsprunorum subsp. persicae, Pseudomonas syringae lachrymans, Pseudomonas syringae tomato or Pseudomonas solanacearum, or Corynebacterium sp., in particular Corynebacterium mich.

The aforementioned diseases can be combated on various plants, such as vegetables, namely a mustard, radish, turnip, celery, potato, tomato, carrot, chicory, bean or bob and pumpkin crops, cereals, nominal small grains (wheat, rice), corn , fruit trees or plants, namely pear trees, apple trees and peach trees, and crop plants not grown for feed and food purposes such as cotton, tobacco, ornamental plants and lawns.

In practice, the compounds of the invention are generally not used alone, but most often form part of compositions comprising a general, in addition to the active ingredient, an inert carrier (or diluent) and / or a surfactant compatible with the active ingredient.

These compositions of the invention typically contain from 0.001 to 95% by weight of the active ingredient and generally contain between 0 to 20% by weight of a surfactant.

By carrier is meant organic or inorganic, natural or synthetic material with which the active ingredient is combined to facilitate its application to the plants, to their seeds or to the soil or soil. Thus, this carrier is generally inert and must be acceptable in agriculture, especially for treated plants. The carrier can be solid (clays, natural or synthetic silicates, silica, chalk, resins, waxes, solid fertilizers, etc.) or liquid (water, alcohols, ketones, petroleum fractions, aromatic or paraffinic hydrocarbons, chlorinated hydrocarbons, liquefied gases, etc. .).

The surfactant may be an emulsifier, dispersant or wetting agent of the ionic or non-ionic type. Examples of suitable agents include polyacrylic acid salts, lignosulfonic acid salts and phenolsulfonic and naphthalenesulfonic acid salts, polycondensation products of ethylene oxide 8 with fatty alcohols, fatty acids, fatty series amines or substituted phenols (especially with alkylphenols, arylphenols or styrylphenols), sulfosuccinic ester salts. acids, taurine derivatives (especially alkyl taurates) and phosphoric acid esters with the condensation products of ethylene oxide with alcohols or phenols. The presence of at least one surface-active agent is generally essential, especially if the carrier is not water-soluble and water is to be used as the vehicle for preparing the dosage form.

The compositions of the invention may be manufactured in a wide variety of solid or liquid forms.

Suitable solid forms are dusts in which the active ingredient content can be up to 100%.

Forms of liquid formulations or formulations which are formulated as liquid application formulations include solutions, in particular water-soluble concentrates, emulsifiable concentrates, emulsions, suspension concentrates, aerosols, wettable powders (or spray powders) and pastes.

Emulsifiable or soluble concentrates most often contain 10 to 90% active ingredient and emulsions or solutions suitable for application contain 0.001 to 20% active ingredient. In addition to the solvent, the emulsifiable concentrates may contain a suitable cosolvent and from 2 to 20% of suitable additives such as stabilizers, surfactants, especially emulsifiers, penetrating agents, corrosion inhibitors, dyes and adhesives.

CS 270 564 02

Emulsions of any desired concentration which are particularly suitable for foliar application can be obtained from these concentrates by dilution with water.

Suspension concentrates, which can also be applied by spraying, are formulated to form a stable, liquid, non-depositing product, and usually contain 10 to 75% active ingredients, 0.5 to 15% surfactants, 0.1 to 10% thixotropic agents, 0 to 10 4 suitable additives such as antifoams, corrosion inhibitors, stabilizers, penetration agents and adhesives, and as a carrier a water or organic liquid in which it is poorly soluble or not soluble at all. Certain organic solids or inorganic salts may be dissolved in the carrier, which additives serve to help prevent sedimentation or act as antifreeze agents.

Wettable powders (or spray powders) are usually formulated to contain from 20 to 95% active ingredients and typically contain, in addition to a solid carrier, 0 to 5% wetting agent, 3 to 10% dispersant and optionally 0 to 10% of one or more stabilizers, or and / or other additives such as penetration agents, adhesives, anti-caking agents, colorants and the like.

An example is the composition of 50% wettable powder:

active ingredient 50 * condensation product of ethylene oxide with fatty alcohol (wetting agent) 2,5 4 the condensation product of ethylene oxide with styrylphenol (dispersant) 5% chalk (inert carrier) 42,5 4

A wettable powder, referred to as another example, has the following composition:

active ingredient (fosethyl-Al) 88.3 A condensation product of ethylene oxide with fatty alcohol (wetting agent) 5.7% condensation product of ethylene oxide with styrylphenol (dispersant) 6 4

To obtain these spray powders or wettable powders, the active ingredient is intimately mixed with the other substances in a suitable mixer and the mixture is ground in mills or other suitable crushers to obtain spray powders with advantageous wettability and suspendability. These powders can be suspended in water at any desired concentration and the resulting suspension can be used very advantageously, especially for application to plant leaves.

As already mentioned, aqueous dispersions and emulsions, for example compositions obtained by diluting a wettable powder or an emulsifiable concentrate according to the invention with water, are also within the scope of the invention. The emulsions thus obtained may be of the water-in-oil or oil-in-water type and may also have a thick consistency, such as mayonnaise.

Granules to be applied to the soil with. they are generally prepared so that their size ranges from 0.1 to 2 mm and can be made by agglomeration or impregnation. In general, these granules contain from 0.5 to 25% of active ingredient and from 0 to 10% of additives such as stabilizers, release retardants, binders and solvents.

The compounds of the invention may also be used in the form of populations. Thus, a composition of 50 g of active ingredient and 950 g of talc may be used, or a composition of 20 g of active ingredient, 10 g of finely divided silica and 970 g of talc may be used. The above ingredients are mixed and ground, and the mixture is applied by dusting.

The invention also provides a method of treating plants against phytopathogenic bacteria. The method comprises administering to these plants an effective amount of a compound of Formula I. An effective amount is an amount sufficient to suppress and destroy bacteria on such plants. These dosages, however, can be varied within wide limits, depending on the bacterium to be controlled, the species of the crop, the climatic conditions and the compound employed.

Claims (2)

SUBJECT OF THE INVENTION Bactericidal composition, characterized in that it contains at least one compound of the formula I as active substance H (R-P-O ') ⁿ M ^{n +} (I) π n in which R represents a hydroxyl group, a C1-C4 alkyl group or a C1-C4 alkoxy group, M is a hydrogen atom, but only when R is a hydroxyl group, or is an alkali metal, alkaline earth metal or aluminum atom and n is an integer of 1 to 3, provided that n is greater than 1, the individual moieties in the meaning of the symbols M may have different meanings. 2. A composition according to claim 1, characterized in that it contains aluminum tris-O-ethyl phosphonate as the active compound of the formula I.