EVALUATION OF DIFFERENT HERBICIDES FOR WEED CONTROL IN ONION

In order to evaluate various herbicides for weed control in onion, an experiment was conducted at Agricultural Research Station Mingora, NWFP during rabi 2004–05. Each replication comprised six herbicides, a hand weeded plot and a weedy check. The pre-transplant herbicides were s-metolachlor @ 1.92 kg, pendimethalin @ 1.32 kg and metribuzin @ 0.35 kg ha-1; the post-transplant herbicides were bromoxynil+MCPA @ 0.45 kg, clodinafop-propargyl @ 0.05 kg and isoproturon @ 1 kg a.i ha-1. Data were recorded on weed density m-2, fresh weed biomass (g m-2), onion count m-2, size of onion bulbs (ml) and onion yield (kg ha-1). Statistical analysis of the data showed that the hand weeded treatment had the lowest weed density (50 m-2) and fresh weed biomass (121 g m-2) followed by pendimethalin (66 m-2) and (272 g m-2) as compared to the weedy check (441 m-2) and (487 g m-2), respectively. Similarly, the maximum size of onion bulbs (79 ml), onion count (50 m-2) and yield (28730 kg ha-1) were recorded in the hand weeded plots followed by pendimethalin (77 ml, 49 m-2 and 28100 kg ha-1) as compared to weedy check (50 ml, 40 m-2 and 11980 kg ha-1)