Demographic parameters of the reduviid predator, Rhynocoris marginatus (Reduviidae: Hemiptera) fed on two lepidopterous insect pests

Abstract

Rhynocoris marginatus (F.) (Reduviidae: Hemiptera:) is an efficient biocontrol agent in the management of multiple insect pests. The study aimed to assess the life table and demographic parameters of R. marginatus feeding on two lepidopterous insect pests, Spodoptera litura (Fab.) (Noctuidae) and Pieris brassicae (Linn.) (Pieridae). The developmental period of all life stages of R. marginatus was shorter when S. litura larvae were provided. The net reproductive rate (R0) was higher (411.4 offspring per individual) on S. litura, while it was 112.4 offspring per individual on P. brassicae. Mean generation time (T) of R. marginatus was shorter (93.28 d) on S. litura than on P. brassicae (105.90 d). Values of the intrinsic rate of increase (0.064 d−1) and finite rate of increase (1.066 d−1) for R. marginatus fed on S. litura were found higher than on P. brassicae (0.044 d−1 and 1.045 d−1, respectively). Age-stage–specific survival rate and age-stage-specific fecundity of R. marginatus were higher feeding on S. litura compared to P. brassicae larvae. The S. litura was the most suitable prey as compared to P. brassicae for R. marginatus. Our study suggests R. marginatus as a useful biocontrol agent against S. litura pest.