Bio-efficacy of acephate 97% DF against major insect-pests of cotton (Gossypium spp.) in Rajasthan

Three dosages of the acephate 97% DF viz., 436.5, 582.0 and 727.5 g a.i. ha⁻¹ along with three treated checks (acephate 75% SP; triazophos 40% EC and profenophos 50% EC) were evaluated against jassids and bollworm complex in cotton during 2011 and 2012. All the treatments were significantly superior over untreated check. Among the treatments, maximum reduction in jassid population 90.2% and 85.6% in 2011 and 81.3% and 82.4% in 2012 was recorded in T₃ after 7 days of first and second spray, respectively, but was at par with acephate 97% DF 582.0 g a.i. ha⁻¹. Minimum bollworm larval population, 2.50 plant⁻¹ and 2.33 plant⁻¹ was recorded in T₃ in 2011 and in T₂ in 2012, respectively. Maximum marketable yield 25.33 and 25.44 q ha⁻¹ was obtained in acephate 97% DF (727.5 g a.i. ha⁻¹) in 2011 and 2012, respectively, but was at par with 24.6 and 24.8 q ha⁻¹ in T₂ acephate 97% DF (582.0 g a.i. ha⁻¹) in 2011 and 2012, respectively.