A physical control technique that irradiate yellow lights at night has been developed to suppress moth species. However, the effects of this method on the fall armyworm (Spodoptera frugiperda) and the growth of maize (Zea mays L.) are unclear. Therefore, this study, for two years, investigated the effects of yellow light irradiation on the growth stages of maize, which is significantly damaged by the fall armyworm. In the first year (2021), yellow lights were set up at the edge of a maize field (second cropping season) after sowing (25th August) and irradiated at night time until harvest (29th October). The growth stage of maize was investigated at 51, 59, and 65 days after sowing. The results indicated that yellow light irradiation retarded the growth of maize after the reproductive growth stage, and the degree of retardation depended on the irradiation intensity and distance. In the second year (2022), the timing of yellow light irradiation, which did not cause growth retardation, was examined. The results showed that yellow light irradiation from sowing to the 5-6 leaf stage did not retard growth retardation after the reproductive growth stage; however, light irradiation from sowing to the 9-10 leaf stage and the later stage retarded growth.
