Comparative efficacy of herbicides and hand weeding to control weeds in onion

Effective and efficient weed management strategies are essential to raise a successful onion crop. Therefore, to find out the economically feasible weed management practice, a field experiment was conducted at Sher-e-Kashmir University of Agricultural Sciences and Technology, Jammu, during 2015–16 and 2016–17. Five herbicides namely pendimethalin1.0 kg/ha, oxyfluorfen 0.15 kg/ha, alachlor 1.0 kg/ha, butachlor 1.0 kg/ha and quizalofop-ethyl 0.05 kg/ha were applied alone or in different combinations replicated thrice in randomized block design. Data was recorded on weed density, dry matter accumulation of weeds, weed control efficiency, weed index, herbicide efficiency index and yield parameters. Pre-emergence application of oxyfluorfen 0.15 kg/ha fb one hand weeding at 40–60 days after transplanting recorded the highest weed control efficiency and the lowest values of weed density, dry matter accumulation of weeds and weed index. The pre-emergence application of oxyfluorfen 0.15 kg/ha fb post-emergence application of quizalofop-ethyl 0.05 kg/ha at 40 DAT was also found to be equally effective in controlling the weeds in onion. The yield attributing traits such as average bulb weight and total bulb yield also exhibited the same pattern. However, the highest B: C ratio was recorded with preemergence application of oxyfluorfen 0.15 kg/ha fb post-emergence application of quizalofop-ethyl 0.05 kg/ha applied 40 DAT. Hence, this treatment can be used for controlling the prevalent weed flora in onion crop under Jammu condition.