Effect of integrated weed management on nutrient uptake and yield of wheat

Field experiment was conducted at Central Research Station, OUAT, Bhubaneswar during rabi, 2013–14 to find out the response of various weed control treatments on nutrient uptake and yield of wheat. The experiment was laid out in randomized block design comprised of twelve treatments viz. pre-emergence application of pendimethalin @ 1.0 kg ha⁻¹ and metribuzin @ 0.3 kg ha⁻¹, metsulfuron @ 0.02 kg ha⁻¹, pendimethalin + one HW at 25 DAS, pendimethalin + 2, 4-D EE @ 0.5 kg ha⁻¹, metsulfuron + one HW at 25 DAS, metsulfuron + 2, 4-D EE @ 0.5 kg ha⁻¹ at 25 DAS, pendimethalin + metsulfuron, metribuzin + metsulfuron, 2, 4-D @0.5 kg ha⁻¹ at 25 DAS and two hand weeding at 25 and 45 DAS were compared with unweeded control. The wheat variety Kalyansona was taken for the purpose. The uninterrupted growth of weeds in unweeded control permitted the weeds to take up the maximum 23.19 kg N, 5.73 kg P and 28.20 kg K ha⁻¹. Application of pendimethalin + one hand weeding to wheat crop removed the greater amount of N, P and K of 79.94, 9.06, 48.87 kg ha⁻¹ respectively. The unrestricted growth of weeds enabled the lowest depletion of nutrients by crop (47.68 kg N, 6.93 kg P and 27.22 kg K ha⁻¹). All the weed control treatments increased significantly the grain and straw yield over the unweeded control. Pre-emergence application of pendimethalin @ 1 kg ha⁻¹ + one hand weeding produced the highest grain (2784 kg ha⁻¹) and straw (2734 kg ha⁻¹). Harvest index was also found to be maximum with the treatment. Maximum reduction in grain yield to the extent of 38.33 per cent was found in unweeded control.