Individual and combined treatments with imidacloprid and spinosad disrupt survival, life-history traits, and nutritional physiology of Spodoptera littoralis

Abstract The Egyptian cotton leafworm Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae) is a pervasive agricultural polyphagous insect pest. Because of the negative side-effects conventional pesticides used in fields, safer alternatives for pest management are required. We evaluated here susceptibility, biological features, and nutritional indices S. after treatment 4 th -instar larvae with neonicotinoid imidacloprid spinosyn spinosad separately or combination. Larvae were fed three successive days on treated leaves castor-bean Ricinus communis using leaf-dip technique (treatment period). In addition, case study, replaced by fresh untreated two (recovery Spinosad was more toxic than imidacloprid, their combination revealed additive effects based co-toxicity factor. Individual combined treatments significantly decreased pupation rate, adult emergence pupal weight, number eggs laid per female, egg-hatch, female longevity, compared to those controls. Pupal malformations recorded. During period, insecticide- time-dependent. On 2 nd day recovery, all not different, results presented herein may help developing effective crop protection methodologies within integrated this insect.