Cultural weed management in rice (Oryza sativa L.) – rice– toria (Brassica campestris L.) sequence under rainfed areas of North-east India

A field experiment was conducted for two consecutive years in organic blocks of Instructional-cum-Research farm of Assam Agricultural University, Jorhat, following randomized block design with eight treatments and three replications. Results revealed that the stale seedbed + 25% reduced spacing + mulching with previous crop residues + one hand weeding (T₄) in rice–rice– toria sequence lowered the weed density by 46.6, 45.7 and 24.4%, and weed dry weight by 71.9, 64.9 and 63.8% at 30, 60 days after transplanting/ sowing and at harvest, respectively as compared to weedy check (T₈). Treatment T₄ also increased the yield and yield attributing parameters as well as the B:C ratio over other treatments in rice–rice– toria sequence. Considering the effect on weed density, weed dry weight, productivity and B:C ratio, the practice of stale seedbed + 25% reduced spacing + mulching with previous crop residues + 1 hand weeding was the best cultural weed management practices in rice–rice– toria cropping sequence.