Bio-efficacy of tolfenpyrad against aphid (Aphisgossypii Glover) infesting okra in Rajasthan

Three dosages of the tolfenpyrad 15% EC, viz. 100, 125 and 150 g along with two treated checks i.e., imidacloprid 17.85 SL @ 22.5 g and acetamiprid 20% WP @ 20 g ai ha⁻¹ and untreated check were evaluated against okra aphid, Aphis gossypii Glover in okra during kharif and rabi 2008–2009. All the treatments were significantly superior over untreated check. Among the treatments, maximum reduction ranged from 90.3 to 100% in aphid population were recorded after 3 and 7 days after spray in tolfenpyrad @ 150 g and imidacloprid 22.5 g ai ha⁻¹ during kharifseason. Similarly, in rabi season at 3 days after first spray, tolfenpyrad @ 150 g gave maximum reduction (92.7%), followed by 90.6 and 90% in imidacloprid and acetamiprid, respectively. The least aphid count was recorded in tolfenpyrad 15% @ 150 g and imidacloprid 17.85 SL @ 22.5 g ai ha-¹, followed by acetamiprid 20% WP @ 20 g ai ha-¹. The natural enemies ’fauna in okra ecosystem had non significant difference among treatments.