A control method against noxious organisms in a field of soybean or corn, which comprises applying one or more PPO-inhibiting compounds selected from the group consisting of flumioxazin, sulfentrazone, saflufenacil, oxyfluorfen and 3-(4-chloro-6-fluoro-2-trifluoromethylbenzimidazol-7-yl)-1-methyl-6-trifluoromethyl-2,4-(1H,3H)pyrimidinedione to soil or weeds in the field where soybean or corn seeds have been sown or where said seeds are to be sown, said seeds being treated with one or more compounds selected from the group consisting of neonicotinoid compounds, azole compounds, strobilurin compounds and metalaxyl compounds.
