Light Quality Influences on Carbon Dioxide Output and Mating of Cabbage Looper Moths

Activity spectra were determined for adult cabbage loopers, Trichoplusia ni (Hubner), maintained under ultraviolet, filtered blue, green, or red fluorescent lighting with 0, 1, 10, or 100% of the diurnal intensity retained during the scotophase. CO2 production and the occurrence of mating were inversely correlated with nocturnal light intensity for UV and green, whereas cyclic red and blue actually enhanced these activities. Considering all light regimes, CO2 output was greatest in response to green, intermediate for red and blue, and least with UV. However, UV illumination resulted in the highest level of mating.