Life table parameters of Helicoverpa armigera (Lep.: Nocutuidae) on cowpea and different chickpea cultivars incorporated into artificial diets

The effect of different artificial diets based on the seeds of one cowpea cultivar (Mashhad) and four chickpea cultivars (Arman, Azad, Binivich and Hashem) on biological and life table parameters of Helicoverpa armigera (Hübner) was studied at 25±1ºC, 65±5% RH and a photoperiod of 16:8 (L:D) hours. The larval period ranged from 13.26 to 21.54 days on Binivich and Mashhad, respectively. The longest and shortest development time of H. armigera was on Hashem (38.62±1.56 days) and Azad 33.81±0.09 days), respectively. The highest fecundity (total number of eggs laid per female) was obtained on Mashhad 1227.23±10.27 eggs) and lowest value of this parameter was on Arman (351.00±1.29 eggs). The highest net reproductive rate (R0) was on Mashhad 250.60 ±0.25 female offspring) and lowest value of this parameter was on Arman (59.49±0.49 female offspring). The intrinsic rate of increase (rm) was the highest on Azad (0.205±0.001 day-1) and lowest on Arman (0.140±0.006 day-1). In different host plants examined, the value of mean generation time (T) ranged from 24.11±0.25 to 30.41±1.30 days and doubling time (DT) ranged from 3.22±0.5 to 4.88±0.25 days. The results indicated that Azad and Arman were the most suitable and unsuitable cultivars incorporated into artificial diet for population growth of H. armigera, respectively.