The present invention relates to synergistic mixtures comprising, as active ingredients 1) an imidazolinone herbicide as compound (I) selected from the group consisting of imazamethabenz-methyl, imazamox, imazapic, imazapyr, imazaquin and imazethapyr; and 2) a fungicidal compound (II) of the formula (1) in which X is —C(═NOCH3)—CONHCH3, —C(═NOCH3)—COOCH3, —C(═CHOCH3)—COOCH3, —N(OCH3)—COOCH3 or —C(═NOCH3)—R, where R is 4H-[1,5,2]dioxazin-3-yl; Y is —O—, —OCH2—, —C(CH3)═NOCH2— or —CH═CH—C(CH3)═NOCH2—; Z is an aromatic ring system being unsubstituted or substituted, selected from phenyl, 2-methylphenyl, 3-trifluoromethylphenyl, 2,5-dimethylphenyl, 4-chlorophenyl, 2,6-dichlorophenyl, 4-chlorphenyl-1H-pyrazol-3-yl, 6-(2-cyanophenoxy)pyrimidin-4-yl, 6-(2-chlorophenoxy)-5-fluoro-pyrimidin-4-yl, 6-trifluoromethyl-pyridin-2-yl, 3-butyl-4-methyl-2-oxo-2H-chromen-7-yl and 3,4-dimethyl-2-oxo-2H-chromen-7-yl; in synergistically effective amounts. Within the scope of the invention, the health of a plant and/or the herbicidal activity and/or the fungicidal activity may be increased synergistically. In addition, the present invention relates to methods for improving the health of plants, for controlling undesirable vegetation in crops and for controlling phytopathogenic fungi in crops, wherein the plant, the locus where the plant is growing or is expected to grow or plant propagation material from which the plant grows is treated with an effective amount of a mixture as defined above.