CH373919A - Method of controlling weeds - Google Patents

Description

  

      Method for controlling weeds The present invention relates to a method for controlling weeds, characterized in that the weeds are treated with amounts of compounds of the formula which are phytotoxic for them:
EMI0001.0005
    where X is a hydrogen atom or a chlorine atom and R is a phenyl radical which is optionally substituted by at least one halogen atom, at least one nitro group or at least one methyl group.



  Examples of active ingredients of the formula (I) are: 1-phenyl-3-chloropyridazon- (6), 1- [p-chlorophenyl] -3-chloropyridazon- (6), 1-phenyl-3 , 5-dichloropyridazon- (6), 1- [p - chlorophenyl] - 3,5-dichloropyridazon- (6), 1- [p -nitrophenyl] -3 - chloropyridazon- (6) , 1- [p-methylphenyl] -3-chloropyridazon- (6), 1- [m-chlorophenyl] -3-chloropyridazon- (6), 1- [2 ', 4',

  5'-trichlorophenyl] -3-chloro-pyridazon- (6).



  Plants that grow in places where they are undesirable should be considered weeds for the purposes of this application. The representatives of the above-mentioned classes of substances act as herbicides even at low concentrations, both against kei emerging seeds and against adult plants.



  The compounds can be used by applying the products evenly to the surface of the soil or of the plants using a mechanical hand spray or spray device. In order to achieve uniform distribution, whoever uses the compounds preferably together with an extender or diluent. As a United diluent z. B. water and / or oil can be used by the active ingredient being dissolved, emulsified or suspended.

   The extender can also be a solid carrier, such as. B. silica, clay or talc. The active ingredient can also be added to commercially available fertilizers and either applied to the surface of the soil or worked into the soil together with them. A mixture with other herbicides or other plant protection products, such as

   B. chlorinated hydrocarbons, urea derivatives or urethanes or phosphoric acid esters are also possible.



  In the following examples, parts mean parts by weight.



  <I> Example 1 </I> 80 parts of 1-phenyl-3,5-dichloro-pyridazon- (6) who with 19.5 parts of solid inert carrier, z. B. kaolin, and 0.5 part adhesive, e.g. B. carboxymethyl cellulose, ground in a suitable ball mill to the greatest fineness. The mixture serves as a dusting agent. When treating a test field with this dust, where 1 kg of active substance per hectare was used, the growth of plantain was prevented in a highly selective manner or it was made to die.



  <I> Example 2 </I> 5 parts of 1-phenyl-3,5-dichloro-pyridazon- (6) are dissolved in 90 parts of an organic solvent, e.g. B. xylene, dissolved and treated with 5 parts of a nonionic emulsifier, e.g. B. an alkylphenol-ethylene oxide condensation product, added. The solution is mixed with water in the desired ratio and forms a milky emulsion for weed control, especially for control of ribwort.



  <I> Example 3 </I> A dust for weed control is produced, similar to that in Example 1, but instead of 80 parts 1-phenyl-3,5-dichloro-pyridazon- (6) one is used equal amount of 1-phenyl-3-chloropyridazon (6).



  The agent acts preferably against dicotyledons and is suitable, for. B. when using 1-3 kg of active substance per hectare to destroy broad-leaf weeds, while oats and maize grow completely normally. The agent is also suitable e.g. B. to burn potato plants as desired.

 

Claims (1)

PATENT CLAIM A method for combating weeds, characterized in that the weeds are treated with amounts of compounds of the formula which are phytotoxic for them EMI0002.0024 wherein X is a hydrogen atom or a chlorine atom and R is a phenyl radical which is optionally substituted by at least one halogen atom, at least one nitro group or at least one methyl group. SUBSTANTIAL CLAIM Process according to patent claim, characterized in that 1-phenyl-3,5-dichloropyridazon- (6) or 1-phenyl-3-chloropyridazon- (6) is used as active ingredient.