Influence of different weed management practices on weed dynamics, yield attributes and economics of black gram

A field experiment was conducted at Birsa Agricultural University, Ranchi, Jharkhand during rainy & winter seasons of 2015-16 and 2016-17. The experiment was laid out in randomized block design with 12 treatments i.e. haloxyfop 81 g/ha, haloxyfop 108 g/ha, haloxyfop 135 g/ha, haloxyfop 270 g/ha, fenoxaprop-p-ethyl 61.9 g/ha, quizalofop-ethyl 43.8 g/ha, imazethapyr 100 g/ha each applied at 20 DAS, pendimethalin 1000 g/ha, oxyfluorfen 100 g/ha each applied at 3 DAS, two mechanical, two hand weeding each performed at 25 and 45 DAS and weedy check, replicated thrice. Black gram var. Birsa Urd-1 was sown at 30 cm using 30 kg seed/ha fertilized with recommended level of nutrients N:P2O5:K2O:Si.e. 25:50:25:25 kg/ha. Mustard var. Pusa-Bold was sown at 30 cm using 5 kg seed/ha fertilized with recommended level of nutrients N:P2O5:K2O:S i.e. 80:40:20:20 kg/ha. The experimental field was mainly infested with Eleusine indica, Echinocloa spp. Commelina spp., Alternanthra sessilis and Cyperus species. Two hand weeding at 25 & 45 DAS recorded higher number of pods/plant, 1000-seed weight, seed yield and harvest index to the extent of 28.90, 16.10, 104.09 and 38.87 per cent, respectively as compare to weedy check i.e. 10.72 pods/plant, 33.80 g, 621 kg/ha and 19.15 per cent, respectively. However, application of haloxyfop 108 g/ha at 20 DAS recorded ` 10,513 and ` 13,878/ha higher net return compared to conventional practice of weed control i.e. two hand weeding at 25 & 45 DAS (` 26,789/ha) and two mechanical weeding at 25 & 45 DAS (` 23,421/ha), respectively and also recorded maximum B: C ratio (1.56).