Field Evaluation of a Nitenpyram-Pyriproxyfen Formulation against Key Cotton Pests, Including the Invasive Jassid Amrasca biguttula , in Two Contrasting Cotton-Growing Zones of Côte d’Ivoire

Abstract

Cotton production in Côte d’Ivoire is constrained by a complex of sucking and fruit-feeding pests, among which the invasive jassid Amrasca biguttula has emerged as a major concern. This study evaluated the field efficacy of a binary formulation containing nitenpyram (200 g/L) + pyriproxyfen (150 g/L) against key cotton pests under contrasting agroecological conditions. Trials were conducted at Bouaké and Nambingué using a randomized complete block design with four replicates. Three doses of the formulation (375, 500, and 750 mL/ha) were compared with an untreated control and a reference insecticide containing acetamiprid (64 g/L) + spinetoram (56 g/L). After treatment, we monitored the abundance of the dominant jassid, Bemisia tabaci , Helicoverpa armigera , and Earias spp., together with jassid damage. Across both sites, all doses of the nitenpyram-pyriproxyfen formulation significantly reduced jassid abundance and associated damage compared with the untreated control and the reference product, with 750 mL/ha providing the most consistent suppression. Effects on Bemisia tabaci were detected only at the site with higher whitefly pressure, whereas no meaningful control of H. armigera or Earias spp. was observed. These findings indicate that the tested formulation was most effective against the dominant jassid and provided only limited control of the other monitored pests under the conditions of this study.