Development, Survival, and Reproduction of Scymnus frontalis (Coleoptera: Coccinellidae), an Imported Predator of Russian Wheat Aphid, at Four Fluctuating Temperatures

摘要: Development, survival, and reproduction of Scymnus frontalis (F.) were stud ied in the laboratory at four temperature regimes with means ranging from 15 to 30°C, daily fluctuations ±5°C. S. has instars a distinct prepupal stage. Developmental times egg adult averaged 79.7, 45.3, 21.4, 17.2 d mean temperatures 15, 18.7, 26.2, respectively. Calculated stage-specific developmental thresholds ranged 10.1°C for first 13.0°C fourth instars. Development required an average 312.2 degree-days above base 11.7°C. Survival was highest two intermediate lowest 15°C mortality being eggs Preoviposition periods 20.5 7.7 30°C. Daily oviposition rates per female during several weeks reproductive life 26.2°C (7.25 day). The proportion females ovipositing (0.97) (0,42). Compared its prey, Diuraphis noxia (Mordvilko), Russian wheat aphid, requires higher complete development reproduce.