effect of artificial diet containing seeds of five corn hybrids on nutritional performance of helicoverpa armigera (lep.: noctuidae)

nutritional indices of helicoverpa armigera (hübner) larvae, an economic insect pest of agricultural crops in the world, were studied on five corn hybrids (sc700, sc704, sc500, dc370 and sc260) when incorporated into artificial diets under laboratory conditions at 25 ± 1 °c, relative humidity of 65 ± 5% and a photoperiod of 16:8 (l: d) h. the highest values of consumption index (ci) and relative growth rate (rgr) for the fourth instars were on sc500 (37.21 ± 3.34 and 0.43 ± 0.07 mg/mg/day, respectively) and lowest values of these indices were on sc704 (21.44 ± 2.83 and 0.18 ± 0.04, respectively). among the five corn hybrids tested, efficiency of conversion of ingested food (eci) of fifth instars was the highest on sc260 (6.92 ± 0.5%) and the highest value of efficiency of conversion of digested food (ecd) was on sc704 (10.71 ± 3%) while the larvae fed on sc700 had the lowest values of eci and ecd (3.57 ± 0.3 and 4.39 ± 0.4%, respectively). for the sixth instar larvae, although the lowest ci and approximate digestibility (ad) values were observed on sc260 (3.49 ± 0.17 and 53.89 ± 3.70%, respectively) the highest value of eci and ecd was on sc260 (9.11 ± 0.6 and 16.54 ± 1.5%, respectively). for all instars (fourth to sixth instars), ecd value of h. armigera was the highest on sc260 (10.15 ± 1.08%) and lowest on sc700 (6.32 ± 0.47%). the result of this study pointed out higher nutritional performance of the larvae h. armigera reared on sc704 and sc260 and lower performance on sc700 and sc500.