Diapause Prevention in Aphidoletes aphidimyza (Diptera: Cecidomyiidae) by Low-intensity Light

Low-intensity radiation at night prevented diapause in larvae of the predatory midge Aphidoletes aphidimyza (Rondani) under environmental conditions (9:15 [L:D] photoperiod and 2l:l5°C [T:C] thermoperiod) that induced 100% diapause when “night” was dark. Diapause incidence was negatively related to radiation per unit area at levels <48 µW/cm2 (<5.5 lx). Larvae did not appear to respond to red light. Lower temperatures (18: 10°C [T:C]) nullified effects of low light intensity, resulting in 89% diapause. In greenhouses, radiation from a 60-W incandescent bulb would prevent diapause in >50% of larvae within a 10-m radius.