Managing Thrips on Roses with Combinations of Neonicotinoide and Biological Insecticides

Abstract

Abstract The purpose of this research was to develop a bio-intensive pest management system for the thrips, Scirtothrips dorsalis Hood (Thysanoptera: Thripidae), on hybrid roses by incorporating biopesticides [spinosad, emamectin benzoate, and Beauveria bassiana (Balsamo) Vuillemin] with neonicotinoides (imidacloprid and acetamiprid) at half the labeled dose. Soil and spray treatments with these insecticides and their combinations were done at 45-d intervals in 2009 and at 60-d intervals in 2010. An imidacloprid drench was the most effective treatment both years. Spinosad-alone, imidacloprid + spinosad, imidacloprid + emamectin benzoate, imidacloprid + B. bassiana, acetamiprid alone, acetamiprid + spinosad, acetamiprid + emamectin benzoate, and acetamiprid + B. bassiana also gave significant control of thrips at four days after spraying. In 2009, spinosad-alone or in combination with imidacloprid remained effective in controlling thrips populations significantly up to 10 d after insecticide treatment. In ...