Effects of Temperature on Hatching and on Longevity of Starved First-Instar Larvae of Hylemya brassicae (Bouché) (Diptera: Anthomyiidae)

Abstract Laboratory studies showed that eggs of Hylemya brassicae required 34 and 67 day-degrees at 10° and 30 °C. and 49 day-degrees at 15°, 20°, and 25 °C. to hatch when 7.2 °C. was used as the threshold temperature for development. Factors that were lethal to the eggs were temperatures above 41 °C. for one hour and periods of desiccation of 1, 1, 2, 5, and 9 days at 30°, 25°, 20°, 15°, and 10 °C., respectively. First-instar larvae survived for approximately 2, 3, 5, and 8 days without food at temperatures of 20°, 15°, 10°, and 5 °C. Starvation for 24 hours immediately after hatching reduced initiation of feeding only slightly.