SK75994A3 - Fungicidal agent on phosphorus acid base and its salts, method of attending by this composition and seeds attended this way - Google Patents

Description

Technical field

The invention relates to seeds of plants protected against fungal infestation, to fungicidal compositions useful for obtaining such protected seeds, and to a method of treating seeds to obtain protected seeds.

More preferably, the invention relates to monocotyledon seeds protected against fungal disease attack, fungicidal compositions useful for obtaining such protected seeds, and a method of treating seeds to obtain protected seeds.

BACKGROUND OF THE INVENTION

It is known that it is possible to control fungal plant diseases by foliar application of phosphorous acid and its derivatives (patent GB 1,459,539), but which has not been practically utilized due to the phytotoxicity of compositions containing these active substances (European patent application 230, 209).

SUMMARY OF THE INVENTION

It has now surprisingly been found that compositions providing a good protective effect to seeds and plants resulting from the germination of these seeds and containing phosphorous acid or derivatives thereof, without the plant protection thus obtained being simultaneously impaired by the excessive phytotoxicity of said compositions.

In the present invention, the term seeds includes any generative part of the plant (propagation material) that can be used to reproduce the plant. The term includes grains (narrower seeds), roots, wildebeest, fruits, onions, tubers, plant parts, germinating plants, young seedlings obtained by any propagation method from grain, cuttings, cell cultures or artificial seeds such as those described in FR 9305192 or PCT / FR 91/00984 (published under WO 92/10087).

More specifically, the invention relates to natural or artificial seeds, preferably monocotyledons, comprising, on the surface or inside, active substances selected from the group consisting of phosphorous acid and salts thereof, in the absence of triazole-2- (4-chlorobenzylidene) - 5,5-dimethyl-l (1 H -1,2,4-triazol-l-ylmethyl) -1-cyclopentanol.

Phosphoric acid is a compound of formula H-P (O) (OH) and (abbreviated as HsPOs). Its salts are known as phosphonates and may include primary and secondary salts, preferably alkali metal or ammonium salts, especially Na 2 HPO 3, K 2 HPO 3 or NH 4 H 2 PO 3.

In practice, the retained amount of the phosphorous-type active substance is usually between 1 g / q and 1 kg / q (q stands for metric cent = 100 kg), preferably between 5 and 500 g / q.

The grain is suitably coated such that one metric cent of grain contains 1 to 500 g of active ingredient, preferably 5 to 300 g of active ingredient.

The phosphorous-type active substance is preferably chosen such that its solubility in water at 20 ° C is higher than 0.1 g / l, more preferably higher than 0.5 g / l and most preferably higher than 50 g / l. Active substances of lower solubility may also be used, but in this case it is necessary to use a correspondingly more complex formulation, for example wettable powders or aqueous suspensions. The advantage of using the active substances with a sufficiently high solubility mentioned above is that in this case the seeds can be treated using simple solutions which are extremely economical.

According to a first variant, the invention further relates to young plants resulting from the germination of the aforementioned seeds, the plants being in the stage of one or two leaves.

The fact that such young plants are obtained in this case is remarkable given that it would be expected that the residual phosphorous acid would have a phytotoxic effect on plants resulting from seed germination which would be the same as the phytotoxic effect manifested by foliar application.

The invention is particularly advantageous in the protection against fungal seed diseases corresponding to crops included in the group comprising cereals, in particular wheat, barley, rye, winter barley, oats, triticale (triticosecale), corn or rice.

The invention is particularly advantageous in the protection of seeds against diseases belonging to the groups Pythium arrhenomanes, Pythium graminicola, Pythium torulosum, Pythium vanterpooli i, Pythium myriotylum, Pythium periilium, Pythium aristosporum, Pythium aphanidermatum, seedlings and necrosis.

The invention further relates to fungicidal compositions intended for the protection of seeds, preferably monocotyledonous seeds, against fungal diseases, comprising:

at least one active ingredient selected from the group consisting of phosphorous acid and salts thereof, at least one agriculturally acceptable inert carrier or surfactant which is agriculturally acceptable, the individual components of these compositions not comprising triazole-

2- (4-chlorobenzylidene) -5,5-dimethyl-1- (1H-1,2,4-triazol-1-ylmethyl) -1-cyclopentanol.

The compositions according to the invention usually contain 0.5 to 95% (by weight) of a phosphorous-type active substance. Preferably, the amount of phosphorous type active ingredient in these dosage formulations is greater than 5% (w / w).

The invention also relates to a method of treating seeds, preferably monocotyledonous seeds, against fungal diseases, which comprises applying to said seeds a fungicidally effective amount of a fungicidally active substance and / or fungicidal compositions. According to the method of the invention, the application of the phosphorous-type fungicidal active ingredient is carried out using compositions comprising at least 5% of the phosphorous-type active ingredient.

Within the scope of the present invention, the term carrier includes a natural or synthetic, organic or inorganic substance with which the active substance is associated in order to facilitate the application of the active substance to the seed. Thus, this carrier is generally inert and must also be agriculturally acceptable, and especially acceptable for the seed to be treated. The carrier may be solid (clays, natural or synthetic silicates, silica, resins, waxes, solid fertilizers and the like) or preferably liquid (water, alcohols, ketones, petroleum fractions, aromatic and paraffinic hydrocarbons, chlorinated hydrocarbons and the like). As mentioned above, preferred carriers are liquid carriers, especially liquid carriers in which the phosphorous active substance is soluble, preferably water and aqueous solutions.

The surfactant may be an emulsifying, dispersing or wetting agent of the ionic or non-ionic type. In this regard, mention may be made, for example, of polyacrylic acid salts, lignosulfonic acid salts, phenolsulfonic or naphthalenesulfonic acid salts, polycondensates of ethylene oxide with fatty alcohols or fatty acids or fatty amines, substituted phenols (especially alkylphenols or arylphenols), ester salts of sulfonates taurine (especially alkyl taurates) or esters of phosphoric acid and polyoxyethylenated phenols or alcohols. The presence of at least one surfactant is often desirable.

The compositions may also contain any other additive, such as a protective colloid, adhesive, thickener, thixotropic agent, penetration agent, stabilizing agent, sequestering agent, pigment, dye or polymer.

In general, the compositions of the invention may be combined with all solid or liquid ingredients which correspond to conventional formulation techniques for seed treatment.

On this occasion, it should be noted that in the vocabulary of those skilled in the art, the term seed treatment in fact refers to grain treatment.

The necessary application techniques are well known, and therefore such conventional application techniques can be used without problems in the present invention.

Application techniques include, for example, film-forming encapsulation or coating. A preferred application technique is coating with respect to its simplicity. In this application, it is sufficient to mix the seeds to be treated with the fungicidal compositions according to the invention.

Of the useful compositions, solid or liquid compositions can generally be mentioned.

Forms of liquid compositions or compositions intended to form liquid compositions immediately prior to final application include solutions, especially water-soluble concentrates, emulsifiable concentrates, emulsions, suspension concentrates or wettable powders (or sprayable powders).

Emulsifiable or water-soluble concentrates most often contain 10 to 80% of the active ingredient, while emulsions or solutions ready for application contain 0.01 to 20% of the active ingredient.

For example, the emulsifiable concentrates may contain, in addition to the solvent, 2 to 20% of suitable additives such as stabilizing agents, surfactants, penetrating agents, corrosion inhibitors, colorants or the aforementioned additives.

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

Wettable powders (or sprayable powders) are usually prepared containing 20 to 95% active ingredient, containing in addition to a solid carrier 0 to 5% wetting agent, 3 to 10% dispersing agent and optionally 0 to 10% one or more stabilizing agents and / or other additives such as pigments, dyes, penetration agents, adhesives, anti-agglomeration agents and the like.

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

It will be routine for a person skilled in the art to select from the above compositions a composition that will be advantageous under existing particular application conditions.

The active substances according to the invention of the phosphorous type can be used alone or in mixtures, in particular with fungicides or insecticides, in particular captan, tiram, aspirin or its salts and esters, salicylic acid or its salts and esters, guazatin, oxine-medf, tefluthrin, anthraquinone or metalaxyl, and insecticides such as imidacloprid, lindane and endosulfan, as well as mixtures of these various products.

In the following, the invention will be explained in more detail by means of specific examples thereof, which are illustrative only and do not limit the scope of the invention, which is clearly defined by the wording of the claims.

DETAILED DESCRIPTION OF THE INVENTION

Example 1

100 g of barley grains are treated with 1.5 ml of aqueous phosphoric acid solution. The specific concentration of the application solution is calculated to give the seeds the dose (in g / q) of the active ingredient shown in the table below. At a dose of 100 g / q, this phosphoric acid concentration is 75 g / l.

This application is carried out by simple mixing / stirring for 1 minute to obtain seeds containing different concentrations of phosphoric acid as indicated in the table below.

The treated grains were placed in pots containing a mixture of peat and pozzolan. One ml of Pythium ground mycelium preparation was inoculated into each pot. There were about 20 grains in each pot.

The grains were germinated and 15 days after sowing, the plants were inspected visually and compared to control grains that were not treated with phosphorous acid and to control grains that were not inoculated with a mythial suspension of Pythium. All the plants they germinated had two leaves. No phytoxicity was observed.

The following results were obtained:

Fungicidal agent Dose (g / q percentage efficiency (%) Pythium arrhenomanes Pythium myriotylium Phosphoric acid 50 60 40 100 100 60 Primary phosphorus- 100 75 20 sodium tan 200 100 70 400 100 100 800 100 100 Control untreated grains 0 0 0

Example 2

The barley grains were treated as in Example 1 with an aqueous solution of secondary potassium phosphite. In order to achieve a dose of 240 g / q (active ingredient on seeds), 100 g of seeds were treated with 1.5 ml of a solution containing 180 g / l of secondary potassium phosphate.

Seed treatment was carried out so that 240 g of phosphite remained deposited on a 1 metric seed barrel.

The treated grains were sown on an open field plot and the condition of the cereal was observed 72 days after sowing and compared to that of control plants derived from untreated grains. All of these cereals were infected with the fungal disease Pythium arrhenomanes.

It was observed that, compared to untreated control plants, the plants derived from the grains treated according to the invention contained 2.8-fold more roots, and the plants themselves were on average 24.3% higher. The dry weight of the roots of the treated plants was 39% greater than that of the untreated roots.

Claims (14)

PATENT CLAIMS 1. Seeds of plants, characterized in that they contain, inside or on the surface, a fungicidally effective amount of a fungicidally active substance selected from the group consisting of phosphorous acid and its salts, in the absence of triazole-2- (4-chlorobenzylidene) - 5,5-dimety1-1- (1 H -1,2,4-triazol-l-ylmety1) -l-cyclopentanol. Monocotyledon seeds, characterized in that they contain a fungicidally effective amount of a fungicidally active compound selected from the group consisting of phosphorous acid and its salts, in the absence of triazole-2- (4-chlorobenzylidene) -5,5-dimethyl-1 - (lH-l, 2,3-triazol-l-ylmethyl) -lcyklopentanolu. Seeds according to claim 1 or 2, characterized in that the phosphorous active substance comprises phosphorous acid or one of its alkali metal or ammonium salts. Seeds according to claim 1 or 2, characterized in that the phosphorous active substance is selected such that its solubility in water at 20 ° C is higher than 0.1 g / l, more preferably higher than 0.5 g / l. Seeds according to one of Claims 1 to 4, characterized in that they comprise a phosphorous active substance in an amount of between 1 g / q and 1 kg / q, preferably between 5 and 500 g / q. Seeds according to one of claims 2 to 5, characterized in that the monocotyledon is selected from the group comprising cereals, in particular wheat, barley, rye, winter barley, oats, triticale, corn and rice. Seeds according to claims 1 to 6, characterized in that they are protected against infestation by diseases selected from the group consisting of Pythium arrhenomanes, Pythium graminicola, Pythium torulosum, Pythium vanterpoolii, Pythium myriotylum, Pythium periilium, Pythium aristosporum and Pythium aristosporum. seeding of key plants, root necrosis and germ necks necrosis. Seeds according to any one of claims 1 to 7, characterized in that they contain a second active ingredient from the group consisting of captan, thiram, guazatine, oxine-copper or metalaxyl, as well as insecticides such as imidacloprid, lindane and endosulfan. Seeds according to any one of claims 1 to 7, characterized in that they contain a second active ingredient from the group comprising aspirin or its salts and esters and salicylic acid or its salts and esters. Young plants, characterized in that they are obtained by germination of the seeds according to any one of claims 1 to 9. Method for treating seeds, preferably monocotyledonous seeds, against fungal diseases, characterized in that an effective amount of a phosphorous active substance from the group comprising phosphorous acid and its salts is applied to the seeds. 12. A fungicidal composition for treating seeds, preferably monocotyledonous seeds, against fungal diseases, comprising at least one active ingredient selected from the group consisting of phosphorous acid and salts thereof, at least one inert, agriculturally acceptable carrier and optionally a surfactant. which is agriculturally acceptable, the individual components of the composition not comprising triazole 2- (4-chloro-benzylidene) -5,5-dimethyl-l- (lH-l, 2,4-triazol-l-ylmethyl) -1-cyclopentanol. A fungicidal composition according to claim 12, characterized in that it contains between 0.5 and 95% of an active substance of the phosphorous type. A fungicidal composition according to any one of claims 12 and 13, characterized in that it is in a liquid, preferably aqueous form.