Demographic parameters of Helicoverpa armigera on ten corn hybrids-mediated artificial diets reveals striking differences

The cotton bollworm, Helicoverpa armigera (Hübner), is a destructive pest feeding on a diverse array of host plants. We studied the demographic parameters of H. armigera on artificial diets prepared from seeds of ۱۰ corn Zea mays L. hybrids (KSC۳۰۱, KSC۴۰۳, KSC۵۴۰, KSC۶۰۰, KSC۶۰۴, KSC۷۰۴, KSC۷۱۱, Maxima, NS۷۷۰, and ZP۶۷۷) using the age-stage, two-sex life table procedure. The results revealed that except for the incubation period, the Z. mays hybrids-mediated artificial diets significantly affected the length of the other immature stages. They also influenced the adult longevity, adult pre-oviposition period (APOP), total pre-oviposition period (TPOP), and oviposition days of H. armigera. Furthermore, the total fecundity of H. armigera was affected by Z. mays hybrids. Accordingly, the females reared on KSC۷۱۱ with ۵۰۳.۳۱ eggs had the highest total fecundity. The highest net reproductive rate (R۰) (۸۸.۴۱ eggs/individual), the intrinsic rate of increase (r) (۰.۱۰۹ day-۱), and finite rate of increase (λ) (۱.۱۱۵ day-۱) were observed on KSC۷۱۱. Our results provided valuable information regarding the life cycle of H. armigera on an artificial diet substrate prepared from different Z. mays hybrids. It was also revealed that although H. armigera had no significant differences in life table parameters on most hybrids, some of them, such as KSC۷۱۱, were very susceptible to damage. One of the issues that emerged from these findings is the possibility of using some hybrids, e.g., KSC۷۱۱, in the preparation of semi-artificial diets for this pest.

Keywords:

artificial diet , life table parameter , nutritional quality , secondary metabolites , seed-based diets