Efficacy of tolfenpyrad 15% EC against whitefly, Bemisia tabaci Gennadius. infesting okra

Three dosages of the Tolfenpyrad 15%EC viz;100, 125 and 150 g 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 whitefly, Bemisia tabaci Gennadius in okra during rabi and kharif 2008–2009. All the treatments were significantly superior over untreated check. The tolfenpyrad @ 150 g. a. i./ha gave maximum reduction, 92.66 to 99.22 and 93.10 to 98.61 per cent, in population over control during rabi and kharif, respectively. The data on mean whitefly population in all treatment during two seasons revealed that the least whitefly count were recorded in tolfenpyrad 15%@ 150 g. a. i./ha was followed by imidacloprid 17.85 SL@22.5 g. a.i./ha and acetamiprid 20%WP@20 g. a.i./ha. Lowest reduction in whitefly population (11.15 to 18.02 and 15.98 to 46.71 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.