Cabbage Looper, Tobacco Budworm, and Beet Armyworm Larval Mortalities, Development and Foliage Consumption on Bt and Non-Bt Cottons

Abstract

Tobacco budworm (TBW), Heliothis virescens (F.), larvae were highly susceptible to feeding on Bt cotton leaves or flower buds with 100% and 96% mortality occurring within 4 days, respectively, compared to an average mortality of 95% for cabbage looper (CL), Trichoplusia ni (Hübner), and 57% for beet armyworm (BAW), Spodoptera exigua (Hübner), after 14 days feeding on Bt leaves. Larval weights, of CL and BAW after 7, 10, or 14 days of feeding on Bt leaves were lower compared with those feeding on non-Bt cotton leaves. BAW, CL, and TBW larvae consumed significantly less Bt leaf area per feeding day compared with DPL 5415.