Nutrients Uptake and Economics of Weed Management Practices in Transplanted Onion (Allium cepa L.)

Field experiments were conducted for two years at Main Horticultural Research and Extension Centre, University of Horticultural Sciences, Bagalkot, Karnataka, during kharif seasons of 2011 and 2012 to study the nutrients uptake and economics of weed management practices in transplanted onion. The experiments comprised of fifteen treatments laid out in randomized block design with three replications. Weed free check significantly reduced the dry weight of weeds at all the stages. Among herbicide treatments, oxyfluorfen @ 0.25 kg ha⁻¹ followed by (fb) oxyfluorfen @ 0.25 kg ha⁻¹ was reduced the dry weight of weeds by 86.21, 85.23 and 84.84 per cent at 30, 60 and at harvest, respectively, compared to unweeded check. At 30 DAT and harvest, farmer's practice showed its superiority in WCI and was on par with oxyfluorfen @ 0.25 kg ha⁻¹ fb oxyfluorfen @0.25 kg ha⁻¹. It also recorded significantly higher bulb yield (19.93 t ha⁻¹). The weed index was also lowest in this treatment. Crop uptake of N, P and K was higher in weed free check at both the stages. Among the herbicide treatments, oxyfluorfen @ 0.25 kg ha⁻¹ fb oxyfluorfen @ 0.25 kg ha⁻¹ (T₁₀) recorded maximum uptake of N, P and K by crop. This treatment also recorded significantly higher gross returns (Rs. 1, 22, 046 ha⁻¹) except weed free check. Maximum net returns (Rs. 87, 163 ha⁻¹) and B: C (3.50) were obtained by application of oxyfluorfen 0.25 kg ha⁻¹ followed by oxyfluorfen 0.25kg ha⁻¹.