Life table parameters and digestive enzymes activity of Helicoverpa armigera (Lep.: Noctuidae) on different tomato cultivars

The tomato fruit borer, Helicoverpa armigera (Hübner), is a destructive insect pest of many host crops in Iran and worldwide. The effect of different tomato cultivars (SUN ۶۱۰۸ f۱, Rio grande UG, Korral, CH falat, Hed rio grande and Cal JN۳) was studied on life table parameters of H. armigera under laboratory (۲۵ ± ۱ °C, ۶۵ ± ۵% RH and a photoperiod of ۱۶: ۸ (L: D) hours), and on the activity of some digestive enzymes of its sixth larval instars under field conditions. The larval period was longest on Hed rio grande (۳۵.۵۰۰ ± ۱.۳۴۰ days) and shortest on Korral (۲۴.۲۹۰ ± ۰.۶۸۸ days). The intrinsic rate of increase (rm) ranged from ۰.۰۹۴ ± ۰.۰۰۳ to ۰.۱۵۹ ± ۰.۰۰۲ (day-۱), which was lowest on Rio grande UG and highest on Korral. The larvae reared on the leaves of SUN ۶۱۰۸ f۱ showed the highest amylolytic activity (۰.۰۶۲ ± ۰.۰۰۰۰۴ mU mg-۱), whereas the lowest activity was in the larvae fed on the leaves of Cal JN۳ (۰.۰۲۷ ± ۰.۰۰۰۰۴ mU mg-۱) and Korral (۰.۰۲۷ ± ۰.۰۰۰۱ mU mg-۱). The amylolytic activity of larvae fed on the fruits of tomato cultivars was highest on Cal JN۳ (۰.۰۴۷ ± ۰.۰۰۰۱ mU mg-۱). Also, the highest general proteolytic activity of H. armigera was in the larvae reared on the leaves of Hed rio grande (۳.۲۳۵ ± ۰.۰۰۴ U mg-۱) and fruits of Rio grande UG (۲.۷۵۷ ± ۰.۱۳۵ U mg-۱). It could be concluded that Rio grande UG is unsuitable host for the growth and development of H. armigera.

کلیدواژه ها:

کرم میوه خوار گوجه فرنگی ، جدول زندگی ، فعالیت آنزیمی ، میزبان گیاهی