Screening of insecticides for management of the invasive Oxycarenus hyalinipennis Costa (Hemiptera: Oxycarenidae) population sourced from urban southern California.

Abstract

Cotton seed bug, Oxycarenus hyalinipennis (Hemiptera: Oxycarenidae), was discovered in southern California in 2019. Surveys have found it within 160 km of cotton producing areas. While often only a minor pest in its native range, there are justified concerns that O. hyalinipennis could become a major pest of US-grown cotton. To proactively prepare for this possibility, 12 US-registered formulations and 1 experimental formulation were assessed in the laboratory for efficacy against O. hyalinipennis, using both contact and ingestion bioassays. Six formulations, consisting of acephate, dinotefuran, flupyradifurone, and imidacloprid with initial efficacy against O. hyalinipennis were used for subsequent dose-response bioassays. These compounds had LC50 values well below maximum labeled rates, although LC99.9 values often exceeded maximum label rates. Results indicate that if O. hyalinipennis infests cotton production regions, both selective and broad-spectrum options will be available for management. These findings establish a baseline for developing an integrated pest management program that can reduce potential damage from O. hyalinipennis, preserve natural enemies, and contribute to resistance management in cotton production areas.