abstract |
The present invention relates to novel pyridazine derivatives of formula (I) as active ingredients which have microbiocidal activity, in particular fungicidal activity: wherein R 1 is methyl, ethyl or isopropyl; R 2 is chloro, fluoro, hydroxy or C 1 -C 2 alkoxy; R 3 is H, chloro, fluoro, methoxy or C 1 -C 3 alkyl; R 4 is chloro, fluoro or bromo; and R 3 is H, fluoro or methoxy; or an agrochemically usable salt form thereof; with the proviso that when R 1 is methyl, R 2 is chloro and R 3 is H, then R 4 or R 5 is different from fluoro. |