Veena Khanna, H.K. Cheema, Poonam Sharma and B.S. Kooner
Abstract
Field efficacy of three native Bacillus thuringiensis (Bt) isolates (BtC-2, Bt C-2 and Bt C-9) and one standard Bt strain (HD-1) viz-a-viz commercial Bt preparation (Halt-5 WP) and recommended insecticides (Thiodan 35EC) was studied for two years (2003-04 and 2004-05). Local Bt isolate Bt C-5 showed the lowest larval popultaion in both the years. Halt-5 WP was on par with I3T C-5. Halt-5 WP C-5 showed significantly low pod damage (18.85 and 18.05%, respectively) as compared to other Bt isolates and control. However, recommended insecticide Thiodan 35 EC showed least mean pod damage (14.3%). Significantly higher yield was observed with BT C-5 and Halt-5 WP than other Bt treatments and control in both the years of testing. Their yields were on par with those of Thiodan 35 EC. Amongst the Bt isolates, BT C-5 was the superior most.