Development, reproduction and life table parameters of Helicoverpa armigera (Lepidoptera: Noctuidae) on five main host plants

The cotton bollworm, Helicoverpa armigera (Hübner), is a destructive pest on a wide range of economic crops in many parts of the world. In this research, demographic parameters of H. armigera were determined on five host plant species including cowpea (cv. Mashhad), navy bean (cv. Dehghan), chickpea (cv. Hashem), soybean (cv. ۰۳۳) and corn (cv. Single cross ۷۰۴). All experiments were carried out under laboratory conditions at ۲۵ ± ۱°C, ۶۵ ± ۵% RH and a photoperiod of ۱۶: ۸ (L: D) h. The results revealed that females and males had the shortest development time on chickpea (۳۶.۱۶ and ۳۴.۹۸ d, respectively) and the longest development time on corn (۴۲.۰۰ and ۴۲.۹۵ d, respectively). The highest daily and total fecundity of H. armigera were observed on cowpea and the lowest ones were on corn. The values of the intrinsic rate of increase (rm) on the above-mentioned host plants were ۰.۱۸۰, ۰.۱۴۴, ۰.۱۶۱, ۰.۱۶۱ and ۰.۱۲۶ day-۱, respectively. Also, the values of the net reproductive rate (R۰) were ۳۶۵.۶۶, ۲۹۴.۲۸, ۳۶۵.۶۷, ۲۳۹.۶۹ and ۱۴۷.۴۰ female offspring, respectively. The longest mean generation time (T) (۳۷.۹۰ ± ۰.۲۶ d) and doubling time (DT) (۵.۶۲ ± ۰.۱۷ d) were observed on corn. Our findings revealed that cowpea and corn were the most susceptible and resistant host plants to H. armigera, respectively.

Keywords:

cotton bollworm , Helicoverpa armigera , corn , cowpea