Effect of tillage and herbicides on grain yield and nutrient uptake by wheat (Triticum aestivum) and weeds

A field experiment was conducted during winter season of 2003–04 and 2004–05 on clayey soil to study the effect of different tillage practices (zero tillage, zero tillage with chemically stale seed-bed, conventional tillage and deep tillage) and herbicides (clodinafop @ 0.06 kg/ha followed by 2,4-D @ 0.5 kg/ha, isoproturon @ 1.0 kg/ha + 2,4-D @ 0.5 kg/ha and weedy check) on nutrient depletion by weeds, and the grain yield and nutrient uptake by wheat (Triticum aestivum L. emend. Fiori & Paol.). The depletion of N, P and K by weeds and uptake by crop were more or less the same under zero, conventional and deep tillage systems. Clodinafop 0.06 kg/ha followed by 2,4-D at 0.50 kg/ha gave 45.88–47.05 and 63.20–66.08 per cent higher grain yield than isoproturon + 2,4-D and weedy check respectively. The N, P and K uptake by wheat increased by 44.29–51.24, 12.00–12.87 and 8.37–9.87 kg/ha due to application of clodinafop followed by 2,4-D, whereas isoproturon + 2,4-D increased the uptake by 10.85–15.50, 3.12–4.63 and 2.31–2.89 kg/ha N, P and K respectively compared with weedy check. Maximum benefit: cost ratio was obtained with zero tillage along with application of clodinafop followed by 2,4-D.