Efficacy of Biocontrol Agents in the Management of Onion Thrips, Thrips tabaci (Lind.) on Onion

Abstract

Application of Beauveria bassiana (Bals) @ 1x 109 spores/ml twice was found to be best treatment with lowest mean thrips population (9.53/plant) with highest per cent reduction (64.15) followed by Verticillium lecanii (Zimmerman) @ 1x109 spores/ml (20 and 30 DAP) with 49.89 per cent reduction. Chrysoperla zastrowi sillemi 20,000 /ac (20 DAP) + B. bassiana @ 1x109 spores/ml (30 DAP) with 41.50 per cent reduction was found to be next best treatment. The treatment with C. z. sillemi @ 20,000 /ac (20 and 30 DAP) was least effective treatment with lowest per cent reduction (28.59).