Weed management practices in Indian mustard (Brassica juncea L.) in lower Gangetic plain Zone

The field experiment was conducted during rabi season in 2017-18 and 2018-19 at the Agronomy Research Farm, A.N.D. University of Agriculture & Technology, Kumarganj, (Ayodhya)to find out the effect of weed management practices on productivity and economics of mustard (Brassica juncea L.). Fifteen treatments were evaluated in randomized block design with three replications. Two hand weedings at 20 and 40 DAS recorded significantly lowest population and dry weight of weeds as compared to rest of the treatments during both the years. Among the herbicides combination, pendimethalin (PE) @ 1000 g ha-1 applied either with hand weeding at 40 DAS or paddy straw mulch @ 10 t ha-1 at 2-3 DAS recorded the lowest weed density and dry weight m-2 followed by metribuzin (PE) @ 175 g ha-1 either with hand weeding at 40 DAS or paddy straw mulch @ 10 t ha-1 at 2-3 DAS. Weedy check till maturity recorded significantly highest density and dry weight of weeds as compared to rest of the treatments during both the years. Pre-emergence spray of pendimethalin (PE) @ 1000 g ha-1 + hand weeding at 40 DAS being at par with two hand weeding at 20 and 40 DAS but recorded highest values of all yield attributes and yields as compared to rest of the treatments. The increase in grain yield due to pendimethalin (PE) @ 1000 g ha-1 + hand weeding at 40 DAS was recorded to the tune of 10.4% over pendimethalin (PE) @ 1000 g ha-1 + paddy straw mulch @ 10 t ha-1 at 2-3 DAS. The yield losses due to weedy check till maturity was recorded to the tune of 58.2%, 53.3% and 43.3% as compared to two hand weeding applied at 20 and 40 DAS, pendimethalin (PE) @ 1000 g ha-1 + hand weeding at 40 DAS, and pendimethalin (PE) @ 1000 g ha-1 + paddy straw mulch @ 10 t ha-1 at 2-3 DAS, respectively. The highest net income (Rs. 57394 ha-1) and B:C ratio (1.5) was recorded with pendimethalin (PE) @ 1000 g ha-1+ hand weeding at 40 DAS which was followed by two hand weeding at 20 and 40 DAS with net income of Rs. 55485 ha-1 and B:C ratio 1.49.