Productivity of winter (rabi) onion (Allium cepa) as influenced by sole and sequential application of herbicides

Abstract

A field experiment was conducted during the winter (rabi) seasons of 201415 and 201516 to study the effect of sole and sequential application of different herbicides on weed control in onion (Allium cepa L.). Sequential ap- plication of pendimethalin @ 750 g/ha at 3 days after transplanting (DAT) + oxyfluorfen @ 100 g/ha at 20 DAT controlled the grasses, sedges and broad-leaf weeds most efficiently and was at par with oxadiargyl @ 90 g/ha at 3 DAT + oxyfluorfen @ 100 g/ha at 20 DAT. Weed competition resulted in about 54.8% yield loss of onion in weedy check plot. The lowest values of total weed density (18.6/m 2), dry weight (6.8 g/m 2), weed index (6.2%) and the highest values of weed control efficiency (89.2%), bulb yield (21.89 t/ha) and benefit: cost ratio (2.84) were registered with sequential application of pendimethalin @ 750 g/ha at 3 DAT + oxyfluorfen @ 100 g/ha at 20 DAT. In weedy check, weeds removed 23.9 kg N, 3.8 kg P and 27.6 kg K/ha.