Effect of weed management on crop productivity of winter maize (Zea mays) + potato (Solanum tuberosum) intercropping system in Shiwalik foothills of Jammu and Kashmir

A field experiment was conducted during the winter season (rabi) 2009–10 and 2010–11 at Jammu. Four intercropping treatments, viz. sole maize, sole potato (Solanum tubrosum L.), maize (Zea mays L.) + potato (additive series) and maize + potato (replacement series), in main plots and 6 methods of weed-control practices, viz. weedy check, weed free, alachlor @1.5 kg/ha pre-emergence, atrazine @ 0.5 kg/ha pre-emergence, alachlor @ 2.0 kg/ha early post-emergence and atrazine @ 0.75 kg/ha post emergence in sub-plots were used to assess the productivity and profitability of winter maize + potato intercropping system. Sole winter maize and sole potato gave significantly higher yields than winter maize + potato grown in additive and replacement series in the respective order. Amongst the intercropping treatments, winter maize + potato (additive series) gave significantly higher yield of 16 t/ha compared to replacement series. Pre-emergence application of atrazine 0.5 kg/ha resulted in significantly lower dry-matter accumulation of all the weed species and highest weed-control efficiency leading to significantly higher crop productivity. Maximum net profit of 92.1 × 10³ /ha was recorded in winter maize + potato (additive series) but higher benefit: cost ratio of 2.3 was recorded with winter maize + potato grown in replacement series with application of either 0.5 kg/ha atrazine or alachlor @ 1.5 kg/ha pre-emergence