Disclosed is a fungicidal composition containing a fungicidally effective amount of a 6-methyl-4,9-dioxo-1,5-dioxonane derivative compound of Formula I, IV or V and at least one triazole fungicide selected from the group consisting of epoxiconazole, prothioconazole and prochloraz, provides synergistic control of selected fungi. The fungi which is controlled may include: wheat brown rust (Puccinia recondita)； stripe rust of wheat (Puccinia striiformis)； leaf blotch of wheat (Mycosphaerella graminicola； Septoria tritici)； glume blotch of wheat (Leptosphaeria nodorum； Stagonospora nodorum)； spot blotch of barley (Cochliobolus sativum； Helminthosporium sativum)； leaf spot of sugar beets (Cercospora beticola)； leaf spot of peanut (Mycosphaerella arachidis； Cercospora arachidicola)； cucumber anthracnose (Glomerella lagenarium； Colletotrichum lagenarium) and black sigatoka disease of banana (Mycosphaerellafijiensis).
