Date of this Version
Sorghum midge, Contarinia sorghicola (Coquillett) diapause was terminated in the laboratory, and factors affecting adult emergence from diapausing larvae were investigated. Temperatures in the range from 20 to 30°C were optimum for diapause termination and adult emergence. Diapausing larvae exposed to moist conditions at 30°C began to emerge as adults after 12 days of incubation. Based on adult emergence rates per day, an emergence threshold temperature was estimated to be 14.8°C. Exposure to 12 to 13 days of continuous moisture at 30°C was essential for diapause termination and adult emergence. Moisture acted to initiate diapause termination, but diapausing larvae were unable to accumulate shorter periods of moisture toward the 12- to 13-day requirement. Photoperiod had no significant effect on the termination of larval diapause.