摘要：The present study was conducted to investigate the impact of cadmium on biology of Spodopteralitura F. and its accumulation in three consecutive generations. The influence of Cd on fecudinty,fertility, incubation period, larval period, adult longevity and total development period was studied atseven different concentrations viz., 1, 5,10,15, 20, 30 and 40 mg/kg apart from control. Pure culture ofS. litura from field collected adult was maintained under laboratory conditions on castor leaves.Fecundity and fertility was low in the highest dose of 40 mg/kg which decreased with generations.Incubation period prolonged with increasing cadmium concentration and generations. The variabledoses of cadmium had significant influence on total larval period of the insect. Longest mean larvalperiod of 23.39 days was recorded at 40 mg Cd/kg which differed statistically from its lowerconcentration. The duration of pupal period decreased with increasing Cd doses as well withgenerations. Thus, increased cadmium concentrations resulted in prolongation of total developmentalperiod of the insect. Irrespective of generations, total developmental period was 33.97 days in thehighest concentration (T7) as compared to control (28.61 days). The accumulation of cadmium in thesixth instar larvae of S. litura increased with increase in dose of heavy metals in artificial diet and withincrease in generations. The accumulation of cadmium in agroecosystem might influence the growthand development of S. litura through host plants to some extent.
