USE OF A SULFUR COMPOUND IN CROPS FOR THE CONTROL OF TOBAMOVIRUS VIRUSES

Abstract

The invention relates to the use of a compound of formula (1) or a composition (C) comprising a compound of formula (1) for the treatment and / or prevention of crop infections by viruses of the genus Tobamovirus. The invention also relates to a method for treating and / or preventing crop infections by viruses of the genus Tobamovirus comprising applying a compound of formula (1) or a composition (C) comprising the compound of formula (1) to the growing media or soils. RS(O)n-Sx-R' (1) No figure.

Description

Title of the invention: USE OF A SULFUR COMPOUND IN CROPS FOR THE FIGHT AGAINST VIRUSES OF THE GENUS TOBAMOVIRUS Field of invention

[0001] The present invention relates to the field of combating viruses of the genus Tobamovirus, and more particularly the use of a sulfur compound, preferably dimethyl disulfide (DMDS), for combating viruses of the genus Tobamovirus.

[0002] The present invention also relates to a method for combating viruses of the genus Tobamovirus in crops using such a sulfur compound, preferably administered drop by drop. Technical background

[0003] The genus Tobamovirus is a genus of plant viruses or phytoviruses, of the Virgaviridae family. It includes different viruses such as tobacco mosaic virus (TMV), tomato mosaic virus (ToMV), ryegrass mosaic virus (HRV), pepper mild mottle virus (PMMV), paprika mild mottle virus and tomato brown rugose fruit virus (ToBRFV).

[0004] These different viruses are a real problem for crops, especially market garden crops. For example, they can reduce their yield, make fruits and vegetables unfit for consumption and spread quickly.

[0005] More specifically, Tomato brown rugose fruit virus (ToBRFV) is a Tobamovirus that was first observed in Israel in 2014. Since then, ToBRFV has also been detected in Europe, Asia, and the Americas. It causes typical Tobamovirus symptoms that include leaf mosaic and chlorosis as well as fruit discoloration and deformation. These symptoms render the fruits unsalable and decrease crop yields. In addition, ToBRFV can overcome the Tm-22 gene in tomato that confers resistance to Tobacco mosaic virus (TMV) and Tomato mosaic virus (ToMV). ToBRFV is also known to cause significant losses in pepper crops.

[0006] The rapid international spread of this virus, combined with its ability to break resistance genes, is causing concern for the fruit and vegetable production industry, and particularly tomato growers worldwide. Measures are being taken and research is being conducted to try to prevent its spread and protect crops. In the case of soilless crops, for example, substrates contaminated by viruses of the genus Tobamovirus must be changed every year and the cost of this operation is very high.

[0007] There is therefore a real need to provide a solution for preventing and / or treating crop infections by viruses of the genus Tobamovirus, in particular by the ToBRFV virus. There is a real need to be able to treat soils and / or crop substrates to eliminate viruses of the genus Tobamovirus, in particular the ToBRFV virus.

[0008] One of the objectives of the present invention is to provide a compound making it possible to prevent and / or treat infections of crops by viruses of the genus Tobamovirus, in particular by the ToBRFV virus.

[0009] One of the objectives of the present invention is to provide a formulation of this compound, easily applicable to crops, in particular by administration to soils and / or substrates.

[0010] An objective of the present invention is to provide a compound and / or a formulation of this compound, suitable for drop-by-drop administration, in particular compatible with irrigation systems.

[0011] Another objective of the present invention is to provide a method for preventing and / or treating, in particular by drop-by-drop administration, infections of crops by viruses of the genus Tobamovirus, more particularly by the ToBRFV virus. Summary of the invention

[0012] The present invention meets all or part of the above objectives.

[0013] The present invention relates to the use of a compound of the following formula (1):

[0014] RS(O)n-Sx-R' (1)

[0015] in which:

[0016] - R is chosen from an alkyl radical, linear or branched, containing from 1 to 4 atoms of carbon, and an alkenyl radical, linear or branched, containing from 2 to 4 carbon atoms;

[0017] - n is equal to 0, 1 or 2;

[0018] - x is an integer chosen from 0, 1, 2, 3 or 4, preferably x represents 1, 2, 3 or 4;

[0019] - R' is chosen from an alkyl radical, linear or branched, containing from 1 to 4 atoms of carbon, and an alkenyl radical, linear or branched, containing from 2 to 4 carbon atoms or, only when n = x = 0, a hydrogen or alkali metal atom,

[0020] for the treatment and / or prevention of infections of crops by viruses of the genus Tobamovirus. Indeed, the present inventors have discovered that the compounds of formula (1) have a virucidal action on viruses of the genus Tobamovirus.

[0021] The present invention also relates to a method for treating and / or preventing infections of crops by viruses of the genus Tobamovirus comprising the application, on the substrates and / or soils of crops, of a compound of formula (1) as defined above.

[0022] Preferably, said compound of formula (1) is dimethyl disulfide (DMDS, of formula CH3-SS-CH3).

[0023] Preferably, the virus is the tomato brown rugose fruit virus.

[0024] In particular, the crops are tomato crops.

[0025] In particular, said compound of formula (1) is formulated in a composition (C) comprising:

[0026] - at least 80% by weight, preferably at least 90% by weight, more preferably between 90% and 95% by weight of at least one compound of formula (1) relative to the total weight of composition (C);

[0027] - between 0.1% and 20% by weight, preferably between 1% and 10% by weight, of at least one surfactant relative to the total weight of the composition (C); and

[0028] - optionally an odor masking agent, for example between 0.1% and 1.5% in weight of an odor masking agent relative to the total weight of the composition (C). Detailed description

[0029] The invention is now described in more detail and in a non-limiting manner in the following description.

[0030] Unless otherwise indicated, all percentages are mass percentages.

[0031] In this text, the quantities indicated for a given species may apply to this species according to all its definitions (as mentioned in this text), including the more restricted definitions.

[0032] Thus, the present invention relates to the use of a compound of formula (1) as defined below for the treatment and / or prevention of infections of crops by viruses of the genus Tobamovirus. The present invention also relates to a method for treating and / or preventing infections of crops by viruses of the genus Tobamovirus comprising the application, to the substrates and / or soils of the crops, of a compound of formula (1) as defined below. Compound of formula (1)

[0033] Said compound of formula (1) is defined according to the following formula:

[0034] RS(O)n-Sx-R' (1)

[0035] in which - R is chosen from a linear or branched alkyl radical containing from 1 to 4 carbon atoms, and a linear or branched alkenyl radical containing from 2 to 4 carbon atoms; - n is equal to 0, 1 or 2; - x is an integer chosen from 0, 1, 2, 3 or 4, preferably x represents 1, 2, 3 or 4; - R' is chosen from a linear or branched alkyl radical containing from 1 to 4 carbon atoms, and a linear or branched alkenyl radical containing from 2 to 4 carbon atoms or, only when n = x = 0, a hydrogen or alkali metal atom.

[0036] As non-limiting examples of radicals R and R', mention may be made of methyl, propyl, allyl and 1-propenyl radicals.

[0037] Preferably, in the compounds of formula (1), n ​​= 0, the compounds then correspond to formula (1'):

[0038] RS-Sx-R' (1')

[0039] in which R and R', identical or different, preferably identical, each represent independently of one another, a linear or branched alkyl radical containing from 1 to 4 carbon atoms, or a linear or branched alkenyl radical containing from 2 to 4 carbon atoms, and x represents 1, 2, 3 or 4.

[0040] A compound of formula (1) or (1') which is very particularly preferred according to the invention is dimethyl disulfide (DMDS).

[0041] The compound of formula (1) can be applied (by fumigation) using coulters or drop by drop onto the substrates and / or soils of the crops. It is more preferably applied drop by drop onto the substrates of the soilless crops.

[0042] Said compound of formula (1) can be applied alone or in mixture with one or more other active compounds known to those skilled in the art such as other pesticides. Composition (C)

[0043] Whether in the context of the use or the process according to the invention, said compound of formula (1) can be formulated in a composition (C) comprising: - at least 80% by weight, preferably at least 90% by weight, preferably between 90% and 95% by weight, of at least one compound of formula (1) as defined above relative to the total weight of the composition (C); - between 0.1% and 20% by weight, preferably between 1% and 10% by weight, of at least one surfactant relative to the total weight of the composition (C); and - optionally an odor masking agent, for example between 0.1% and 1.5% by weight of an odor masking agent relative to the total weight of the composition (C).

[0044] In particular, said composition (C) comprises a single compound of formula (1).

[0045] Preferably, composition (C) comprises: - at least 90% by weight, for example between 90% and 95% by weight, of a compound of formula (1) as defined above, preferably DMDS, relative to the total weight of composition (C); - between 1% and 10% by weight of at least one surfactant relative to the total weight of composition (C); and - optionally between 0.1% and 1.5% by weight of an odor masking agent relative to the total weight of composition (C).

[0046] Preferably, composition (C) comprises, or even consists of: - at least 90% by weight of a compound of formula (1) as defined above, preferably DMDS, relative to the total weight of composition (C); - between 1% and 10% by weight, preferably between 1% and 6% by weight, of at least one (Cio-Ci3)alkyl-benzene-sulfonate relative to the total weight of composition (C); and - optionally between 0.1% and 1.5% by weight of an odor masking agent relative to the total weight of composition (C).

[0047] The composition (C) according to the invention may correspond in a most preferred manner to the dimethyl disulfide compositions marketed by the company Arkema under the names Paladin® EC, Accolade® EC, Atomal® 13 and SEKAMTEAU®. SEKAMTEAU® is particularly preferred. According to one embodiment, said composition (C) does not comprise water.

[0048] The composition (C) according to the invention can be prepared by any method known to those skilled in the art, for example by simple mixing of its components, optionally with stirring and heating, the order of addition of the components not influencing the composition (C).

[0049] Preferably, composition (C) is used when the compound of formula (1) is applied dropwise. Surfactants

[0050] The surfactants included in composition (C) are in particular surfactants of a predominantly hydrophilic nature, i.e. those having an HLB ("Hydrophilic Lipophilie Balance") greater than or equal to 8. They may be of anionic, cationic, non-ionic or amphoteric nature.

[0051] As non-limiting examples of anionic surfactants, mention may be made of:

[0052] - alkali metal, alkaline earth metal, ammonium or triethanolamine salts of alkyl-, aryl- or alkylaryl-sulfonic acids, fatty acids at basic pH, sulfosuccinic acid or alkyl, dialkyl, alkylaryl or polyoxyethylene-alkylaryl esters of sulfosuccinic acid;

[0053] - alkali or alkaline earth metal salts of sulfuric acid esters, phos- phoric, phosphonic or sulfoacetic and saturated or unsaturated fatty alcohols, as well as their alkoxylated derivatives;

[0054] - alkali or alkaline earth metal salts of alkylarylsulfuric acids, alkyla- arylphosphoric, alkylarylsulfoacetic, as well as their alkoxylated derivatives.

[0055] The cationic surfactants that can be used are, for example, those of the family of quaternary alkylammoniums, sulfoniums or fatty amines at acid pH, as well as their alkoxylated derivatives. As non-limiting examples of non-ionic surfactants, mention may be made of alkoxylated alkylphenols, alkoxylated alcohols, alkoxylated fatty acids, glycerol fatty esters or fatty sugar derivatives.

[0056] The amphoteric surfactants that can be used are, for example, alkyl betaines or alkyl taurines.

[0057] The preferred surfactants according to the invention are compounds based on alkyl-benzene-sulfonate and / or alkoxylated alkyl-phenol. More particularly, (Ci0-Ci3)alkyl-benzene-sulfonates (also called salts of Ci0-Ci3 alkyl derivatives of benzene sulfonic acid) are used, for example the calcium salts of Ci0-Ci3 alkyl derivatives of benzene sulfonic acid (CAS number 1335202-81-7) and in particular their mixtures in any proportion. Said (Ci0-Ci3 )alkyl-benzene-sulfonates may or may not be mixed with other surfactants, for example with non-ionic surfactants, optionally in the presence of an organic solvent such as 2-ethylhexan-1-ol.

[0058] The surfactants used may be in the form of commercial compositions, for example Atlox™ 485 IB marketed by Croda, T-Mulz® TE-CP marketed by Harcros Chemicals.

[0059] Odor masking agent:

[0060] Certain compounds of formula (1) have a strong, unpleasant, or even aggressive odor. In particular, DMDS has a strong and aggressive odor due partly to the presence of strongly odorous impurities and partly to the garlicky and ethereal odor intrinsic to this molecule. The same is true for most organic sulfides.

[0061] Generally speaking, the oxides of these organic sulfides, in particular DMSO, have a less aggressive odor. However, depending on the concentrations of impurities, this odor can be unpleasant and bothersome for the end user.

[0062] Any type of known odor masking agent may be used in the composition of the invention. By "odor masking agent" is meant a compound or a composition comprising several compounds making it possible to reduce, eliminate or mask the odor of the compound of formula (1) used.

[0063] For example, we can cite chloropicirin, generally used to odorize methyl bromide.

[0064] In particular, an odor masking agent may be used as described in application WO 2011 / 012815 incorporated herein by reference.

[0065] Said odor masking agent may comprise at least one monoester, at least one di- and / or triester, at least one alcohol, at least one ketone and optionally at least one terpene.

[0066] According to a preferred embodiment, the odor masking agent comprises:

[0067] al) from 1% to 40% by weight of at least one monoester;

[0068] a2) from 10% to 70% by weight of at least one di- and / or triester;

[0069] a3) from 1% to 30% by weight of at least one alcohol;

[0070] a4) from 0.5% to 20% by weight of at least one ketone of formula Ra-CO-Rb, in in which Ra represents a hydrocarbon chain comprising from 1 to 6 carbon atoms, linear or branched, optionally comprising one or more unsaturations in the form of double bond(s), and Rb represents a cyclic hydrocarbon chain or a linear or branched hydrocarbon chain optionally but preferably substituted by a cyclic structure, Rb comprising from 6 to 12 carbon atoms, optionally comprising one or more unsaturations in the form of double bond(s) and being optionally substituted by one or more hydroxyl groups; and

[0071] a5) optionally up to 20% by weight of at least one terpene.

[0072] The percentages of a1, a2, a3, a4 and a5 are percentages by weight expressed relative to the total weight of the odor masking agent.

[0073] Unless otherwise stated, “ppm” means parts per million by weight.

[0074] Said odor masking agent may therefore comprise from 1% to 40%, preferably of 2% to 35%, more preferably 5% to 30% by weight, relative to the total weight of the odor masking agent, of at least one monoester mentioned under al).

[0075] As illustrative, but not limiting, examples of monoesters mentioned under a1), mention may be made of esters of saturated or unsaturated C2-C2o acids, such as acetates, propionates, butyrates, methylbutyrates, pentanoates, hexanoates, heptanoates, caproates, oleates, linoleates, linolenates, of ethyl, propyl, butyl, pentyl, 2-methylbutyl, iso-amyl, hexyl, benzyl, phenylethyl, menthyl, carvyl, and others, as well as mixtures thereof.

[0076] More particularly preferred are iso-amyl acetate, hexyl acetate, 2-methylbutyl butyrate, iso-amyl butyrate, benzyl acetate, phenylethyl acetate and mixtures of these compounds.

[0077] The odor masking agent may also comprise at least one di- and / or triester a2), in an amount of between 10% and 70% by weight, preferably between 15% and 65% by weight, more preferably between 20% and 60% by weight, relative to the total weight of the odor masking agent. Mention may be made, in a non-limiting manner, of at least one di- and / or triester chosen from ortho-phthalates, such as diethyl ortho-phthalate; citrates, such as triethyl citrate; and malonates, such as diethyl malonate.

[0078] The odor masking agent may also comprise from 1% to 30%, preferably from 5% to 25% by weight relative to the total weight of the odor masking agent, of at least at least one alcohol a3), advantageously at least one mono-alcohol comprising from 1 to 30 carbon atoms, preferably from 6 to 20 carbon atoms, more preferably from 8 to 11 carbon atoms, said carbon atoms forming a linear or branched chain optionally comprising one or more unsaturations in the form of double bond(s), and optionally comprising a cyclic structure with 5 or 6 members, saturated, or totally or partially unsaturated.

[0079] The alcohols defined above are preferably monoalcohols, the hydroxyl function preferably being carried by an sp2 carbon atom. It should be understood that the hydroxyl function can also be carried by a carbon atom included in a cyclic structure as defined above.

[0080] The alcohols used in the odor masking agent and as defined above are advantageously and by way of non-limiting examples chosen from menthol, neomenthol, phenylethyl alcohol, benzyl alcohol, citronellol, dihydro-myrcenol, dihydroterpineol, dimetol, ethyl-linalool, geraniol, linalool, tetra-hydrolinalool, tetrahydromyrcenol, nerol, and others, as well as mixtures of two or more of them.

[0081] The ketone or ketones indicated under a4) above are chosen, by way of non-limiting examples, and preferably, from damascones, damascenones, ionones, irisones, methylionones, frambinone (CAS No. 5471-51-2), and others, as well as mixtures thereof. The amount of ketone(s) is advantageously between 0.5% and 20%, preferably between 1% and 10% by weight relative to the total weight of the odor-masking agent.

[0082] The odor masking agent may optionally also comprise up to 20%, preferably from 1% to 10% by weight relative to the total weight of the odor masking agent, of at least one terpene.

[0083] Examples of terpenes, indicated under a5), which may be used include, but are not limited to, terpinenes, myrcene, limonene, terpinolene, pinenes, sabinene, camphene, and others, mixtures of two or more of them, as well as terpene-based essences, in particular those comprising these ingredients.

[0084] Furthermore, the odor masking agent usable in the context of the present invention may comprise, in minor quantities, other agents (fragrances) usually used in the field of perfumery, and in particular one or more compounds carrying aldehyde and / or cyclic ketone function(s), among which may be mentioned, in a non-limiting manner, geranial, neral, citronellal, menthone, iso-menthone, 1,8-cineole, ascaridole, flavonone, and mixtures thereof.

[0085] The odor masking agent may, if appropriate, or even if necessary, further comprise one or more additives commonly used in the field. Such additives may for example be chosen from, and in a non-limiting manner, solvents, pigments, dyes, preservatives, biocides, and others.

[0086] Among the solvents, particularly preferred examples are alcohols, ethers, esters and glycols. Particularly advantageously, the solvent is chosen from diethyl phthalate, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, polyethylene glycols, polypropylene glycols, and mixtures thereof, and even more advantageously from diethyl phthalate, dipropylene glycol, and mixtures thereof.

[0087] A typical odor masking agent composition comprises (by weight relative to the total weight of the odor masking agent):

[0088] - from 5% to 30% by weight of at least one monoester al), chosen from acetate iso-amyl, ethyl methyl-2-butyrate, iso-amyl butyrate, phenylethyl acetate, ethyl caproate, benzyl acetate, hexyl acetate and mixtures thereof;

[0089] - from 20% to 60% by weight of at least one di- and / or triester a2) chosen from ortho-phthalates, such as diethyl ortho-phthalate; citrates, such as triethyl citrate; and malonates, such as diethyl malonate, and mixtures thereof;

[0090] - from 5% to 25% by weight of at least one alcohol, preferably at least two alcohols, more preferably at least three alcohols, as described previously under a3);

[0091] - from 1% to 10% by weight of at least one ketone, preferably at least two ketones, more preferably at least three ketones, as described previously under a4); and

[0092] - from 1% to 10% by weight of at least one, preferably at least two, preferably a mixture of terpenes referenced above under a5).

[0093] A representative, but non-limiting, example of an odor masking agent is reproduced below, wherein each of the components comprises one, several, or all of the listed compounds:

[0094] Component a1): 16.00% comprising benzyl acetate, hexyl acetate, isoamyl acetate, phenylethyl acetate, ethyl caproate, ethyl methyl-2-butyrate

[0095] Component a2): 50.00% comprising diethyl malonate, diethyl phthalate

[0096] Component a3): 20.60% comprising phenylethyl alcohol, citronellol, geraniol, linalool, cis-3-hexenol

[0097] Component a4): 4.50% comprising l-(4-hydroxyphenyl) butan-3-one, alpha-irisone

[0098] Component a5): 7.00% orange terpenes Others: 1.90% including citral, ethylmaltol, ethylmethyl phenylglycidate

[0099] These compositions are given as examples. Cultures and Substrates

[0100] The crops according to the invention may be both soilless crops and field crops. Preferably, said crops are soilless crops. Preferably, said crops are market garden crops and / or fruit crops (for example, small fruit crops and red fruits such as blueberries, raspberries, strawberries and blackberries) and / or nurseries.

[0101] In particular, these are cultures of:

[0102] - the Solanaceae family and more particularly tomatoes, paprika, peppers, chilies, potatoes and tobacco;

[0103] - the Cucurbitaceae family and more particularly cucumbers and melons;

[0104] - the Fabaceae family, in particular green beans and peas;

[0105] - the Rosaceae family such as strawberries, raspberries and blackberries;

[0106] - the Ericaceae family, for example blueberries; and

[0107] - ornamental flowers.

[0108] Particularly preferably, the crops are crops of tomatoes, tobacco, red fruits, potatoes and ornamental flowers, in particular soilless crops of tomatoes.

[0109] The term "substrate" refers in particular to any type of support used for growing plants and which is different from soil. In the case of soilless crops, the substrate is thus a solid support on which the plant can cling and grow. Nutrients generally arrive in the substrate thanks to the fertilizers contained in the irrigation water.

[0110] The substrates for soilless crops can be chosen from: - non-organic substrates (sand, gravel, pebbles, perlite, rock wool, horticultural felt, vermiculite), - organic substrates (rice husks, potting soil, peat, sawdust, straw, coconut fiber), and - synthetic substrates (flakes, sponges, plastic fibers capable of absorbing moisture).

[0111] Mention may preferably be made of coconut fibers (in particular coconut fiber loaves), potting soils, peats and rock wool, preferably coconut fibers. Virus

[0112] The compounds of formula (1) as defined above can be used in the fight against viruses of the genus Tobamovirus. They have in particular a virucidal activity on the latter. Among the viruses of the genus Tobamovirus, mention may be made of: tobacco mosaic virus (TMV), tomato mosaic virus (ToMV), ryegrass mosaic virus (HRV), pepper mild mottle virus (PMMV ), paprika mild mottle virus and Tomato brown rugose fruit virus (ToBRFV), preferably Tomato brown rugose fruit virus (ToBRFV ). Viruses of the genus Tobamovirus are notably described in the publication Hakan FIDAN et al. Journal of Integrative Agriculture 2021, 20(8): 2170-2179.

[0113] Application of the compound of formula (1) or of the composition (C)

[0114] Whether in the context of the use or the process according to the invention, the compound of formula (1) can be applied by any technique known to those skilled in the art.

[0115] The compound of formula (1), and in particular DMDS, can be a fumigant. More particularly, the compound of formula (1) is in liquid form and transforms into gas after application to contaminated substrates and / or soils (fumigation): it can thus act against viruses of the genus Tobamovirus present.

[0116] The compound of formula (1) may for example be applied by dripping, using coulters, by direct pouring onto the substrates and / or soils or by injection into the substrates, for example using a syringe. Preferably, it is applied by dripping. The compound of formula (1) may be applied alone or formulated, for example formulated in composition (C) as defined above.

[0117] For example, when the compound of formula (1) is applied using coulters, it can be used as such or formulated with one or more surfactants such as those mentioned above for composition (C). The amount of surfactants can be between 1 and 10% by weight, relative to the total weight of the formulation.

[0118] Said composition (C) can also be applied by drip, using coulters, by direct pouring onto the substrates and / or soils or by injection into the substrates, for example using a syringe. Preferably, it is applied by drip. Composition (C) can be diluted before application, in particular in water. It can advantageously be diluted in water and distributed in the irrigation systems of the crops to be treated.

[0119] Preferably, the compound of formula (1) or the composition (C) according to the invention is administered to the substrates and / or soils of the crops before planting.

[0120] For example, the compound of formula (1) or the composition (C) according to the invention is injected into the irrigation system of the substrates and / or soils of the crop(s), then administered drop by drop, before the establishment of the crop(s) (i.e. before planting). Thus, the use and / or the method according to the invention may comprise the following steps: a. application of the compound of formula (1) or of composition (C) to the substrate and / or the soil to be treated, preferably by drop by drop; b. establishment of the culture(s) on said substrate and / or soil.

[0121] The treatment can be easily adapted by a person skilled in the art depending on the crop to be treated, the nature of the soil and / or the substrate and the climatic conditions.

[0122] Preferably, the compound of formula (1) according to the invention is applied, for example injected into irrigation systems, at a concentration of between 0.01 and 1% by weight, preferably between 0.1 and 1% by weight, more particularly between 0.1 and 0.5% by weight, relative to the weight of the water (irrigation water).

[0123] Preferably, the composition (C) according to the invention is applied, for example injected into irrigation systems, at a concentration of between 0.01 and 1% by weight, relative to the weight of the water (irrigation water). More particularly, the composition (C) is applied at a concentration of between 0.1 and 0.5%, more preferably between 0.1 and 0.4% by weight relative to the weight of the water (irrigation water).

[0124] In particular, the compound of formula (1) or the composition (C) is administered at a dose ranging from 1 to 400 L / ha, preferably ranging from 30 to 240 L / ha, more preferably 120 L / ha.

[0125] In a particularly preferred manner, the method according to the invention comprises the following steps: - possibly remove as much plant material as possible from the soilless growing substrates and / or from the growing soils; - install or reinstall the application system, preferably the drip system; - possibly place the soilless growing substrates and / or the soil and the irrigation system under barrier film; - injecting the compound of formula (1) or composition (C) into the irrigation system at a concentration of between 0.01 and 1% and / or at a dose of between 1 and 400 L / ha (preferably at a dose of 120 L / ha); - possibly remove the barrier film after 14 days. Administration by drop

[0126] Drip irrigation can be carried out by any conventional drip irrigation system. Such drip irrigation systems or devices (also called trickle irrigation systems or micro-irrigation systems or drip in English) are widely known and are generally used to supply water and possibly an irrigation liquid such as a liquid fertilizer to plants to be grown in the soil of agricultural land or plantations, in the substrates of soilless crops or the like.

[0127] In addition to the conventional irrigation device, these systems comprise for example a supply and / or a reservoir for the compound of formula (1) optionally formulated or the composition (C) as defined above and optionally a device for dosing said compound of formula (1) optionally formulated or said composition (C). The supply of compound of formula (1) optionally formulated or in composition (C) can be provided by any means known per se, and for example from a reservoir containing them. The reservoir can be equipped with a pump and advantageously with a dipping rod, as described in international application WO 2014 / 147034. The composition (C) according to the invention can also be applied in the form of an emulsion (F) as described in patent application WO 2021 / 038165 incorporated here by reference.

[0128] All of the lines including the drippers, or even the entire drip irrigation system, as well as the soil and / or the substrate to be treated, may be covered with a barrier film (i.e., impermeable to fumigant vapors) before application of said fumigant. This prevents the fumigant from dissipating into the atmosphere and thus protects operators and preserves the environment. Different types of barrier films, such as SIF (“semi-impermeable film”), VIF (“virtually impermeable film”), or TIF (“totally impermeable film”) type films, are currently used when treating soils and / or substrates by fumigation. Said barrier film may be a photocatalytic film as described in application WO 2013 / 030513. For example, “BARRIER-FILM NFT54-195-1 / 2 CL2” films may be used.

[0129] The methods and uses according to the present invention can be combined or alternated with other conventional pesticide type treatments or other fumigant treatments.

[0130] The invention will be explained in more detail in the following examples. EXAMPLES

[0131] Unless otherwise stated, the percentages are expressed by weight relative to the total weight of the composition. Example 1: Composition (C) according to the invention

[0132] A composition (C) according to the invention comprising:

[0133] - 95% by weight of DMDS; and

[0134] - 5.00% by weight of surfactants based on calcium salts of C alkyl derivatives 10-C13 benzenesulfonic acid,

[0135] is prepared by mixing the different constituents. Example 2: Virucidal treatment according to the invention

[0136] The effectiveness of DMDS (dimethyl disulfide), formulated in composition (C) according to Example 1, was tested on tomato plants grown above ground and in greenhouses in Turkey. The substrates used for these plants are of the coconut fiber loaf type (called coconut loaves).

[0137] ToBRFV infection:

[0138] The coconut cakes were used in a previous tomato crop. This The previous crop was infected with Tomato brown rugose fruit virus (ToBRFV). After harvesting the tomatoes, the plants were pulled from the coconut slabs. The infected coconut slabs are reused to test the efficacy of DMDS against ToBRFV.

[0139] The infection of coconut cakes is verified by PCR on the root residues remaining in the cakes, in accordance with the method described in the document “Journal of Integrative Agriculture 2021, 20(8): 2170-2179 Robust molecular detection of the new Tomato brown rugose fruit virus in infected tomato and pepper plants from Turkey”. I. Materials and Methods:

[0140] The infected coconut cakes were covered with a transparent barrier film TIF “Totally Impermeable Film” and connected to a drip irrigation system with a computerized automated system (Karaca Control System).

[0141] Before application, a calibration was carried out to indicate the water content that could be used for each plot. The moisture percentage of the cakes was also controlled (60-70%). DMDS, in the form of composition (C) of Example 1, was applied to the coconut cakes using the irrigation system.

[0142] After application of DMDS, the irrigation system was flushed.

[0143] The barrier film was removed 10 days after the application of DMDS.

[0144] A barrier film was also placed on the control plots, receiving only water.

[0145] The planting of the tomato plants was then carried out using plants from a nursery certified free of viruses and bacteria.

[0146] Nine treatments, as described below, at different doses of DMDS were carried out, with 4 repetitions for each treatment.

[0147] Information regarding the application is given in the following Table 1:

[0148] [Tableauxl] Application of virucidal treatment Number of bars / ha 6,000 Number of drippers / bar 4 Flow rate of one dripper 2L / h Water flow rate 6,000 bars x 4 drippers x 2L / h = 48,000 L / h / ha Application rates at 0.1% 30L / ha 60L / ha 90L / ha - - - Number of bars / treatment 480 480 480 - - - Quantity of composition (C) / bar 5 ml 10 ml 15 ml - - - Concentration 0.1% 0.1% 0.1% - - - Application time 37.50' 75.00' 112.50' - - - Rinsing time 5' 5' 5' - - - Application rates at 0.4% 30L / ha 60L / ha 90L / ha 120L / ha 180L / ha 240L / ha Number of bars / treatment 480 480 480 480 480 480 Quantity of composition (C) / bar 5 ml 10 ml 15 ml 20 ml 30 ml 40 ml Concentration 0.4% 0.4% 0.4% 0.4% 0.4% 0.4% Application time 9.38' 18.75' 28.13' 37.50' 56.25' 75.00' Rinse time 5' 5' 5' 5' 5' 5'

[0149] The roots of the treated plants, as well as those of the control plants, were then collected in order to determine the infection by the tomato brown rugose fruit virus by PCR, in accordance with the method described in the document “Journal of Integrative Agriculture 2021, 20(8): 2170-2179 Robust molecular detection of the new Tomato brown rugose fruit virus in infected tomato and pepper plants from Turkey”.

[0150] The results are shown in Table 2 below:

[0151] [Tables2] Trial Treatment Identification of ToBRFV before application Identification of ToBRFV after application 1 30L / ha at 0.4% Positive Negative 2 60L / ha at 0.4% Positive Negative 3 90L / ha at 0.4% Positive Negative 4 120L / ha at 0.4% Positive Negative 5 180L / ha at 0.4% Positive Negative 6 240L / ha at 0.4% Positive Negative 7 30L / ha at 0.1% Positive Negative 8 60L / ha at 0.1% Positive Negative 9 90L / ha at 0.1% Positive Negative 10 (control) None Positive Positive

[0152] These results show the high efficacy of DMDS as a virucide for tomato brown rugose fruit virus: for all infected tomato plants, the presence of the virus was not detected following treatment, whatever the dose and concentration tested.

Claims

Claims

1. Use of a compound of the following formula (1): RS(O)n-Sx-R' (1) in which: - R is chosen from a linear or branched alkyl radical containing from 1 to 4 carbon atoms, and a linear or branched alkenyl radical containing from 2 to 4 carbon atoms; - n is equal to 0, 1 or 2; - x is an integer chosen from 0, 1, 2, 3 or 4, preferably x represents 1, 2, 3 or 4; - R' is chosen from a linear or branched alkyl radical containing from 1 to 4 carbon atoms, and a linear or branched alkenyl radical containing from 2 to 4 carbon atoms or, only when n = x = 0, a hydrogen or alkali metal atom, for the treatment and / or prevention of infections of crops by viruses of the genus Tobamovirus.

2. Use according to claim 1, in which the compound of formula (1) is a compound of the following formula (U): RS-Sx-R' (1') in which R and R', identical or different, each independently represent: a linear or branched alkyl radical containing from 1 to 4 carbon atoms, or a linear or branched alkenyl radical containing from 2 to 4 carbon atoms and x represents 1, 2, 3 or 4.

3. Use according to claim 1, wherein the compound of formula (1) is dimethyl disulfide (DMDS).

4. Use according to any one of the preceding claims, wherein said compound of formula (1) is formulated in a composition (C) comprising: - at least 80% by weight of said compound of formula (1) according to any one of claims 1 to 3, relative to the total weight of the composition (C); - between 0.1% and 20% by weight of at least one surfactant, relative to the total weight of the composition (C); and - optionally an odor masking agent.

5. Use according to any one of claims 1 to 4, characterized in that the virus is chosen from the tobacco mosaic virus ( TMV), Tomato mosaic virus (ToMV), Ryegrass mosaic virus (HRV), Pepper mild mottle virus (PMMV), Paprika mild mottle virus and Tomato brown rugose fruit virus (ToBRFV), preferably Tomato brown rugose fruit virus (ToBRFV).

6. Use according to any one of claims 1 to 5, characterized in that the crops are chosen from crops of the Solanaceae family, the Cucurbitaceae family, the Fabaceae family, the Rosaceae family, the Ericaceae family and ornamental flowers; preferably the tomato crop.

7. A method of treating and / or preventing infections of crops by viruses of the genus Tobamovirus comprising the application, to the substrates and / or soils of the crops, of a compound of formula (1) as defined in any one of claims 1 to 3.

8. Treatment and / or prevention method according to claim 7, wherein said compound of formula (1) is formulated in a composition (C) comprising: - at least 80% by weight of said compound of formula (1) relative to the total weight of the composition (C); - between 0.1% and 20% by weight of at least one surfactant relative to the total weight of the composition (C); and - optionally an odor masking agent.

9. Treatment and / or prevention method according to claim 7 or 8, characterized in that the compound of formula (1) or composition (C) is injected into the crop irrigation systems at a concentration of between 0.01% and 1% by weight relative to the weight of the water and / or at a dose ranging from 1 to 400 L / ha.

10. Treatment and / or prevention method according to any one of claims 7 to 9, characterized in that the compound of formula (1) or the composition (C) is administered to the substrates and / or soils of the crops before planting.