Effect of four host plants on nutritional performance of cotton leafworm, Spodoptera littoralis (Lepidoptera: Noctuidae)

Effects of four vegetable host plants, artichoke, cabbage, potato and tomato on nutritional indices of the cotton leafworm Spodoptera littoralis (Boisduval) (Lep.: Noctuidae), were studied under laboratory conditions (25 ± 1 °C, 65 ± 5% RH, with a 16: 8 L: D photoperiod). Fourth instar reared on tomato showed the highest approximate digestibility (AD) (90.406 ± 1.125%) and efficiency of conversion of ingested food (ECI) (30.249 ± 4.128%). The highest values of efficiency of conversion of digested food (ECD) and ECI of fifth instars (38.663 ± 4.34 and 20.083 ± 1.581%, respectively) were on artichoke and the lowest of both values on cabbage (ECD: 6.314 ± 1.128 and ECI: 5.448 ± 1.052%).The 3rd to 6th instars as a whole showed the highest ECD and ECI values on tomato (23.412 ± 2.252 and 19.845 ± 1.798%, respectively). However, the highest and lowest values of consumption index (CI) were on cabbage (33.943 ± 2.669) and tomato (6.145 ± 0.578). The highest values of relative consumption rate (RCR) and (AD) were obtained on cabbage (1.49 ± 0.109 mg/mg/day and 86.431 ± 1.141%, respectively). The results of nutritional indices and the cluster analysis indicate that tomato was nutritionally the most suitable food for S. littoralis.