Pesticide treatment of soils or substates with sulphur compounds

Abstract

In order to replace methyl bromide in all the uses thereof in soil or substrate treatment, the invention relates to the use of at least one sulphur compound having general formula: wherein R represents an alkenyl or alkyl radical, n is equal to 0, 1 or 2, x is a number between 0 and 4 and R′ represents an alkenyl or alkyl radical or, only if n=x=0, a hydrogen or alkali-metal atom. The sulphur compounds (in particular dimethyldisulphide) can be applied according to standard soil treatment methods (by injection, spraying, dripping, sprinkling) and said compounds have no phototoxic effects.

1 . Pesticidal (nematicidal, fungicidal, insecticidal and bactericidal) treatment of soils or substrates, preferably by fumigation, characterized in that there is applied to the soil or in the substrate at least one sulphur compound of general formula:  
       
         
           
           
               
               
           
         
       
       in which R represents an alkyl or alkenyl radical containing from 1 to 4 carbon atoms, n is equal to 0, 1 or 2, x is a number ranging from 0 to 4, and R′ represents an alkyl or alkenyl radical containing from 1 to 4 carbon atoms or, only if n=x=0, a hydrogen or alkali metal atom.  
     
     
         2 . Treatment according to  claim 1 , in which the radicals R and R′ of the compound(s) of formula (I) are chosen from methyl, propyl, allyl and 1-propenyl radicals.  
     
     
         3 . Treatment according to  claim 1  or  2 , in which the number n of the compound(s) of formula (I) is equal to zero.  
     
     
         4 . Treatment according to one of  claims 1  to  3 , in which the sulphur compound is a disulphide.  
     
     
         5 . Treatment according to one of  claims 1  to  4 , in which the sulphur compound is DMDS.  
     
     
         6 . Treatment according to one of  claims 1  to  5 , in which the sulphur compound is applied in the pure state or in the form of an aqueous emulsion, a microemulsion, a solution in a biodegradable solvent or a product which is microencapsulated or supported by a solid.  
     
     
         7 . Treatment according to one of  claims 1  to  6 , in which the compound(s) of formula (I) is(are) applied at a dose between 150 and 1000 kg/ha.  
     
     
         8 . Treatment according to  claim 7 , in which the sulphur compound has no phytotoxic effect.  
     
     
         9 . Treatment according to one of  claims 1  to  8 , combined with a treatment (simultaneous or otherwise) with one or more other pesticidal substances.