| abstract |
O.Z. 0050/37263 Abstract of the Disclosure: 4H-Pyrido[2,3-d][1,3]oxazin-4--one derivatives of the formula where Y is oxygen or sulfur and R is phenyl which is unsubstituted or substituted by halogen, haloalkyl, halo-alkoxy, haloalkylmercapto, haloalkylsulfinyl or haloalkyl-sulfonyl, processes for their manufacture, and their use for controlling undesirable plant growth. |