Abdelhammid Gacemi - Department of Agronomic Sciences and Biotechnology, Faculty of Natural and Life Sciences, Hassiba Benbouali, University of Chlef, Algeria.
Ahmed Taibi - Department of Agronomy, Faculty SNV/STU, University Aboubakr Belkaid, Tlemcen, Algeria.
Nour El Houda Abed - National Institute of Agronomic Research of Algeria, Algiers, Algeria.
Mahfoud M'hammedi Bouzina - Department of Agronomic Sciences and Biotechnology, Faculty of Natural and Life Sciences, Hassiba Benbouali, University of Chlef, Algeria.
Djamel Bellague - National Institute of Agronomic Research of Algeria, Algiers, Algeria.
Kheirddine Tarmoul - National Institute of Agronomic Research of Algeria, Algiers, Algeria.

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 (۲۵ ± ۱ °C, ۶۵ ± ۵% RH, with a ۱۶: ۸ L: D photoperiod). Fourth instar reared on tomato showed the highest approximate digestibility (AD) (۹۰.۴۰۶ ± ۱.۱۲۵%) and efficiency of conversion of ingested food (ECI) (۳۰.۲۴۹ ± ۴.۱۲۸%). The highest values of efficiency of conversion of digested food (ECD) and ECI of fifth instars (۳۸.۶۶۳ ± ۴.۳۴ and ۲۰.۰۸۳ ± ۱.۵۸۱%, respectively) were on artichoke and the lowest of both values on cabbage (ECD: ۶.۳۱۴ ± ۱.۱۲۸ and ECI: ۵.۴۴۸ ± ۱.۰۵۲%).The ۳rd to ۶th instars as a whole showed the highest ECD and ECI values on tomato (۲۳.۴۱۲ ± ۲.۲۵۲ and ۱۹.۸۴۵ ± ۱.۷۹۸%, respectively). However, the highest and lowest values of consumption index (CI) were on cabbage (۳۳.۹۴۳ ± ۲.۶۶۹) and tomato (۶.۱۴۵ ± ۰.۵۷۸). The highest values of relative consumption rate (RCR) and (AD) were obtained on cabbage (۱.۴۹ ± ۰.۱۰۹ mg/mg/day and ۸۶.۴۳۱ ± ۱.۱۴۱%, respectively). The results of nutritional indices and the cluster analysis indicate that tomato was nutritionally the most suitable food for S. littoralis.

Host plants, Lepidoptera, Noctuidae, Nutritional indices, Spodoptera littoralis