Use of a sulphur compound in crops for controlling viruses of the tobamovirus genus

Abstract

The present invention relates to the use of a compound of formula (1): R-S(O)n-Sx-R' or a composition (C) comprising a compound of formula (1): R-S(O)n-Sx-R' for the treatment and / or prevention of crop infections by viruses of the Tobamovirus genus. The invention also relates to a method for treating and / or preventing crop infections by viruses of the Tobamovirus genus, which comprises applying to the growing media or cultivation soils a compound of formula (1): R-S(O)n-Sx-R' or a composition (C) comprising the compound of formula (1): R-S(O)n-Sx-R'.

Description

[0001] Description

[0002] Title: USE OF A SULFUR COMPOUND IN CROPS TO FIGHT VIRUSES OF THE GENUS TOBAMOVIRUS

[0003] Field of invention

[0004] The present invention relates to the field of combating viruses of the genus Tobamovirus, and more particularly to the use of a sulfur compound, preferably dimethyl disulfide (DMDS), for combating viruses of the genus Tobamovirus.

[0005] The present invention also relates to a method for controlling viruses of the genus Tobamovirus in crops using such a sulfur compound, preferably administered drop by drop.

[0006] Technical background

[0007] The genus Tobamovirus is a genus of plant viruses or phytoviruses, in the Virgaviridae family. It includes various 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). These different viruses are a real problem for crops, especially vegetable crops. For example, they can reduce their yield, make fruits and vegetables unfit for consumption and spread rapidly.

[0008] 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, which confers resistance to Tobacco mosaic virus (TMV) and Tomato mosaic virus (ToMV). ToBRFV is also known to cause significant losses in pepper crops.

[0009] The rapid international spread of this virus, combined with its ability to disrupt resistance genes, is causing concern for the fruit and vegetable production industry, 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 annually, and this is very expensive.

[0010] There is therefore a real need to provide a solution to prevent and / or treat 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.

[0011] One of the objectives of the present invention is to provide a compound for preventing and / or treating infections of crops by viruses of the genus Tobamovirus, in particular by the ToBRFV virus.

[0012] 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.

[0013] 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.

[0014] 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.

[0015] Summary of the invention

[0016] The present invention meets all or part of the above objectives.

[0017] The present invention relates to the use of a compound of the following formula (1):

[0018] RS(O) n -Sx-R' (1) in which:

[0019] - 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;

[0020] - n is equal to 0, 1 or 2;

[0021] - 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. Indeed, the present inventors have discovered that the compounds of formula (1) have a virucidal action on viruses of the genus Tobamovirus.

[0022] 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 above.

[0023] Preferably, said compound of formula (1) is dimethyl disulfide (DMDS, of formula CH3-SS-CH3).

[0024] Preferably, the virus is Tomato Brown Rugose Fruit Virus.

[0025] In particular, the crops are tomato crops.

[0026] In particular, said compound of formula (1) is formulated in a composition (C) comprising:

[0027] - 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);

[0028] - 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 composition (C); and

[0029] - 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 composition (C).

[0030] Detailed description

[0031] The invention is now described in more detail and in a non-limiting manner in the following description.

[0032] Unless otherwise stated, all percentages are by mass.

[0033] 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.

[0034] Thus, the present invention relates to the use of a compound of formula (1) as defined below for the treatment and / or prevention of crop infections by viruses of the genus Tobamovirus. The present invention also relates to a method for treating and / or preventing crop infections 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.

[0035] Said compound of formula (1) is defined according to the following formula:

[0036] RS(O) n -Sx-R' (1) in which

[0037] 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;

[0038] 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.

[0039] Non-limiting examples of radicals R and R' include methyl, propyl, allyl and 1-propenyl radicals.

[0040] Preferably, in compounds of formula (1), n ​​= 0, the compounds then correspond to formula (T):

[0041] RS-Sx-R' (T) 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.

[0042] A compound of formula (1) or (T) which is very particularly preferred according to the invention is dimethyl disulfide (DMDS).

[0043] The compound of formula (1) can be applied (by fumigation) using coulters or by drip treatment on the substrates and / or soils of the crops. It is more preferably applied by drip treatment on the substrates of soilless crops.

[0044] 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)

[0045] Whether in the context of the use or the method according to the invention, said compound of formula (1) may 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).

[0046] In particular, said composition (C) comprises a single compound of formula (1).

[0047] Preferably, the 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 the composition (C); between 1% and 10% by weight of at least one surfactant relative to the total weight of the composition (C); and optionally between 0.1% and 1.5% by weight of an odor masking agent relative to the total weight of the composition (C).

[0048] Preferably, the 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 the 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 the composition (C); and optionally between 0.1% and 1.5% by weight of an odor masking agent relative to the total weight of the composition (C).

[0049] 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.

[0050] 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).

[0051] Preferably, composition (C) is used when the compound of formula (1) is applied dropwise.

[0052] Surfactants

[0053] 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 anionic, cationic, non-ionic or amphoteric in nature.

[0054] Non-limiting examples of anionic surfactants include: alkali metal, alkaline earth metal, ammonium metal or triethanolamine salts of alkyl-, aryl- or alkylaryl-sulfonic acids, basic pH fatty acids, sulfosuccinic acid or alkyl, dialkyl, alkylaryl or polyoxyethylene-alkylaryl esters of sulfosuccinic acid; alkali metal or alkaline earth metal salts of sulfuric, phosphoric, phosphonic or sulfoacetic acid esters of saturated or unsaturated fatty alcohols, and their alkoxylated derivatives; alkali metal or alkaline earth metal salts of alkylarylsulfuric, alkylarylphosphoric, alkylarylsulfoacetic acids, and 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. Non-limiting examples of non-ionic surfactants include alkoxylated alkylphenols, alkoxylated alcohols, alkoxylated fatty acids, glycerol fatty esters or fatty sugar derivatives.

[0056] Suitable amphoteric surfactants are, for example, alkyl betaines or alkyl taurines.

[0057] The preferred surfactants according to the invention are compounds based on alkylbenzenesulfonate and / or alkoxylated alkylphenol. More particularly, (C-Ci3)alkylbenzenesulfonates (also called salts of C10-C13 alkyl derivatives of benzenesulfonic acid) are used, for example the calcium salts of C10-C13 alkyl derivatives of benzenesulfonic acid (CAS number 1335202-81-7) and in particular mixtures thereof in any proportion. Said (C-Ci3)alkylbenzenesulfonates 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. The surfactants used may be in the form of commercial compositions, for example Atlox™ 4851 B marketed by Croda, T-Mulz® TE-CP marketed by Harcros Chemicals.

[0058] Odor masking agent:

[0059] Some compounds of formula (1) have a strong, unpleasant, or even aggressive odor. In particular, DM DS 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.

[0060] Generally, the oxides of these organic sulfides, particularly DMSO, have a less aggressive odor. However, depending on the impurity concentrations, this odor can be unpleasant and bothersome to the end user.

[0061] 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 for reducing, eliminating or masking the odor of the compound of formula (1) used.

[0062] For example, we can cite chloropicirin, generally used to odorize methyl bromide.

[0063] In particular, an odor masking agent as described in application WO 2011 / 012815 incorporated herein by reference may be used.

[0064] 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.

[0065] According to a preferred embodiment, the odor masking agent comprises: a1) from 1% to 40% by weight of at least one mono-ester; a2) from 10% to 70% by weight of at least one di- and / or triester; a3) from 1% to 30% by weight of at least one alcohol; a4) from 0.5% to 20% by weight of at least one ketone of formula Ra-CO-Rb, 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 a5) optionally up to 20% by weight of at least one terpene.The percentages of a1, a2, a3, a4 and a5 are percentages by weight expressed relative to the total weight of the odor masking agent.

[0066] Unless otherwise stated, “ppm” means parts per million by weight.

[0067] Said odor masking agent may therefore comprise from 1% to 40%, preferably from 2% to 35%, more preferably from 5% to 30% by weight, relative to the total weight of the odor masking agent, of at least one monoester mentioned under a1).

[0068] As illustrative, but not limiting, examples of monoesters mentioned under a1), mention may be made of esters of saturated or unsaturated C2-C20 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.

[0069] More particularly preferred are iso-amyl acetate, hexyl acetate, 2-methylbutyl butyrate, iso-amyl butyrate, benzyl acetate, phenylethyl acetate and mixtures of these compounds.

[0070] 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.

[0071] 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 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.

[0072] The alcohols previously defined 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 previously defined.

[0073] The alcohols used in the odor masking agent and as defined above are advantageously and by way of non-limiting examples chosen from menthol, neo-menthol, phenylethyl alcohol, benzyl alcohol, citronellol, dihydromyrcenol, dihydroterpineol, dimetol, ethyl-linalool, geraniol, linalool, tetrahydrolinalool, tetrahydromyrcenol, nerol, and others, as well as mixtures of two or more of them.

[0074] The ketone or ketones indicated under a4) above are chosen, by way of non-limiting examples, and preferably, from damascenes, damascenones, ionones, irisones, methylionones, frambinone (CAS No. 5471-51-2), and others, as well as mixtures thereof. The quantity 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.

[0075] 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.

[0076] 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 these, as well as terpene-based essences, in particular those comprising these ingredients.

[0077] 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.

[0078] 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, but not limited to, solvents, pigments, dyes, preservatives, biocides, and others.

[0079] 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.

[0080] A typical odor masking agent composition comprises (by weight relative to the total weight of the odor masking agent): - from 5% to 30% by weight of at least one monoester a1), chosen from isoamyl acetate, ethyl methyl-2-butyrate, isoamyl butyrate, phenylethyl acetate, ethyl caproate, benzyl acetate, hexyl acetate and mixtures thereof;

[0081] - 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;

[0082] - 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);

[0083] - 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

[0084] - from 1% to 10% by weight of at least one, preferably at least two, preferably a mixture of, terpenes referenced above under a5).

[0085] A representative, but non-limiting, example of an odor masking agent is reproduced below, wherein each of the components comprises one, more, or all of the listed compounds:

[0086] Component a1): 16.00% including benzyl acetate, hexyl acetate, isoamyl acetate, phenylethyl acetate, ethyl caproate, ethyl methyl-2-butyrate

[0087] Component a2): 50.00% including diethyl malonate, diethyl phthalate

[0088] Component a3): 20.60% including phenylethyl alcohol, citronellol, geraniol, linalool, cis-3-hexenol

[0089] Component a4): 4.50% including 1-(4-hydroxyphenyl) butan-3-one, alpha-irisone

[0090] Component a5): 7.00% orange terpenes

[0091] Others: 1.90% including citral, ethylmaltol, ethylmethyl phenylglycidate These compositions are given as examples.

[0092] Cultures and Substrates

[0093] 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.

[0094] In particular, these are crops of: - the Solanaceae family and more particularly tomatoes, paprika, peppers, chilies, potatoes and tobacco;

[0095] - the Cucurbitaceae family and more particularly cucumbers and melons;

[0096] - the Fabaceae family, in particular green beans and peas;

[0097] - the Rosaceae family such as strawberries, raspberries and blackberries;

[0098] - the Ericaceae family, for example blueberries; and

[0099] - ornamental flowers.

[0100] Particularly preferably, the crops are tomato, tobacco, red fruit, potato and ornamental flower crops, especially soilless tomato crops.

[0101] The term "substrate" refers to any type of support used for growing plants that is different from soil. In the case of soilless cultivation, the substrate is a solid support on which the plant can cling and grow. Nutrients generally arrive in the substrate thanks to fertilizers contained in the irrigation water.

[0102] Substrates for soilless cultivation can be chosen from: inorganic 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).

[0103] We can preferentially cite coconut fibers (in particular coconut fiber cakes), potting soils, peat and rock wool, preferably coconut fibers.

[0104] Virus

[0105] The compounds of formula (1) as defined above can be used in the fight against viruses of the genus Tobamovirus. They have in particular 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). The viruses of the genus Tobamovirus are notably described in the publication Hakan FIDAN et al. Journal of Integrative Agriculture 2021, 20(8): 2170-2179.

[0106] Application of the compound of formula (1) or of composition (C)

[0107] 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.

[0108] The compound of formula (1), and in particular DM DS, 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.

[0109] 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.

[0110] 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.

[0111] Said composition (C) may 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) may be diluted before application, in particular in water. It may advantageously be diluted in water and distributed in the irrigation systems of the crops to be treated.

[0112] 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.

[0113] 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 the composition (C) to the substrate and / or the soil to be treated, preferably by drop by drop; b) establishment of the crop(s) on said substrate and / or soil. 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.

[0114] 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).

[0115] 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).

[0116] In particular, the compound of formula (1) or 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.

[0117] Particularly preferably, the method according to the invention comprises the following steps: optionally removing as much plant material as possible from the soilless growing substrates and / or from the soils of the crop; setting up or resetting the application system, preferably the drip system; optionally placing the soilless growing substrates and / or the soils and the irrigation system under a 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 ranging from 1 to 400 L / ha (preferably at a dose of 120 L / ha); optionally removing the barrier film after 14 days.

[0118] Drip administration

[0119] Drip administration 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 optionally 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. In addition to the conventional irrigation device, these systems comprise for example a supply and / or a reservoir for the optionally formulated compound of formula (1) or composition (C) as defined above and optionally a device for dosing said optionally formulated compound of formula (1) or said composition (C).The supply of compound of formula (1) optionally formulated or of composition (C) can be ensured 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 herein by reference.

[0120] All lines including the drippers, or even the entire drip irrigation system, as well as the soil and / or 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, thereby protecting operators and preserving the environment. Different types of barrier films, such as SI F (“semi-impermeable film”), VIF (“virtually impermeable film”), or TIF (“totally impermeable film”), 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.

[0121] The methods and uses according to the present invention can be combined or alternated with other conventional pesticide-type treatments or other fumigant treatments.

[0122] The invention will be explained in more detail in the following examples.

[0123] EXAMPLES

[0124] Unless otherwise stated, percentages are expressed by weight relative to the total weight of the composition.

[0125] Example 1: Composition (C) according to the invention

[0126] A composition (C) according to the invention comprising:

[0127] 95% by weight of DM DS; and

[0128] 5.00% by weight of surfactants based on calcium salts of C10-C13 alkyl derivatives of benzene sulfonic acid, is prepared by mixing the different constituents.

[0129] Example 2: Virucidal treatment according to the invention

[0130] 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 coconut fiber loaves (called coconut loaves).

[0131] ToBRFV infection:

[0132] The coconut slabs were used in a previous tomato crop. This previous crop was infected with Tomato brown rugose fruit virus (ToBRFV). After harvesting the tomatoes, the plants were removed from the coconut slabs. The infected coconut slabs were reused to test the efficacy of DMDS against ToBRFV.

[0133] The infection of coconut cakes is verified by PCR on the root residues remaining in the cakes, according to 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”.

[0134] I. Materials and Methods:

[0135] The infected coconut cakes were covered with a transparent barrier film Tl F “Totally Impermeable Film” and connected to a drip irrigation system with a computerized automated system (Karaca Control System).

[0136] 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%). DM DS, in the form of composition (C) of Example 1, was applied to the coconut cakes using the irrigation system. After application of DM DS, the irrigation system was rinsed.

[0137] The barrier film was removed 10 days after DMDS application. A barrier film was also placed on the control plots, receiving only water.

[0138] Tomato plants were then planted using plants from a nursery certified free of viruses and bacteria. Nine treatments, as described below, at different doses of DMDS were carried out, with 4 replicates for each treatment.

[0139] Information regarding the application is given in the following Table 1: [Table 1] Roots from treated plants, as well as from control plants, were then collected to determine infection with Tomato brown rugose fruit virus by PCR, according to 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”.

[0140] The results are shown in Table 2 below: [Table 2]

[0141] These results demonstrate 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, regardless of 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 (T): RS-Sx-R' (T) 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, in which 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 composition (C); - between 0.1% and 20% by weight of at least one surfactant, relative to the total weight of composition (C); and - possibly an odor masking agent.

5. Use according to any one of claims 1 to 4, characterized in that the virus is chosen from 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 cultivation of tomatoes.

7. 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 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 composition (C); - between 0.1% and 20% by weight of at least one surfactant relative to the total weight of the composition (C); and - possibly 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.