Bio-efficacy of tolfenpyrad 15% EC against jassid (Amrasca biguttula biguttula Ishida) infesting okra

Three dosages of the Tolfenpyrad 15%EC viz; 100, 125 and 150 g a. i. along with two treated checks ie., imidacloprid 17.85 SL @ 22.5 g and acetamiprid 20%WP@ 20 g a.i./ha and untreated check were evaluated against jassid, Amrasca biguttula biguttula Ishida. in okra during rabi and kharif 2008–2009. All the treatments were significantly superior over untreated check. The tolfenpyrad @ 150 g. a. per ha gave maximum reduction, 89.84 to 97.85 and 84.52 to 100.00 per cent, in population over control during rabi and kharif, respectively. The data on mean jassids population in all treatments during two seasons revealed that the least jassids count were recorded in tolfenpyrad 15%@ 150 g. a. i. per ha which was followed by imidacloprid 17.85 SL@22.5 g. a.i. per ha and acetamiprid 20%WP@20 g. a.i. per ha. Lowest reduction in jassid population (7.50 to 27.40 and 15.25 to 26.66 per cent) was recorded in tolfenpyrad 100 g. a. i./ha at 3^rd and 7^th days after spray in both seasons, respectively. The natural enemies fauna in okra ecosystem had non significant differences among treatments.