The present invention pertains to an agricultural and horticultural bactericide/fungicide composition comprising (A) at least one agricultural and horticultural bactericide/fungicide selected from a group consisting of benzimidazole guanidine organosulfur anilinopyrimidine triazole organochlorine and organocopper bactericide/fungicides (B) a dialkyl sulfosuccinate and (C) a polyoxyethylene C alkyl ether at a mass ratio (A) : (B) : (C) of 1 70 : 1 : 1 4. This composition enhances restores or sustains the effect of the bactericide/fungicide.
