Evaluation of integrated weed management practices for onion in Pakistan

Weed management studies in transplanted onion were conducted during 2004 and 2005 at the National Agricultural Research Centre, Islamabad, Pakistan. Pendimethalin and oxadiazon were applied post-emergence 2 days and 4 week after transplanting and their efficacy alone and in combination with one manual weeding was evaluated to reduce weed competition and its effects on marketable bulb yield. Hand weeded and weedy check were included. Compared to weed free condition, weed crop competition caused 71% and 76% reduction in the marketable bulb yield during the first and second year, respectively. Cyprus rotundus (41%) and Coronopus didymus (19%) were the dominant weeds recorded in the field. Both pendimethalin and oxadiazon when applied 2 DAT in combination with one weeding at 60 DAT were found more effective in enhancing marketable bulb yield and recorded higher net returns than other treatments.