Effects of the Heavy Metal Cu2+ on Growth, Development, and Population Dynamics of Spodoptera litura (Lepidoptera: Noctuidae)

ABSTRACT Spodoptera litura (F.) larvae were fed with artificial food containing four different concentrations of copper (25, 50, 100, and 200 mg/kg). Copper affected growth, development, and population dynamics of late instar larvae. Our results indicate that the fourth and fifth instar survival rates were significantly reduced at 50–200 mg/kg copper (Cu2+). Moreover, all the Cu2+ treatments significantly reduced pupation and moth emergence rates in a dose-dependent manner. Larvae fed 25 or 50 mg/kg Cu2+ showed significant reductions in development period compared with non-Cu controls, and the pupation duration of animals fed 200 mg/kg was significantly longer than in non-Cu controls. All Cu2+ concentrations significantly reduced individual pupal weights compared with controls. In addition, Cu2+ at some concentrations significantly affected fertility parameters, such as doubling population time (DT), the net reproduction rate (R0 ), the mean generation time (T), the intrinsic rate of increase (rm ), and t...