Effect of weed management on yield and nutrient uptake in mustard (Brassica juncea)

Abstract

Field investigation was carried out during rabi season of 2014-15 at Udaipur to evaluate the effect of different weed management practices on yield and nutrient uptake of mustard. The maximum seed yield was registered with two hand weeding (1955.25 kg ha-1) except weed free check and was at par with fluazifop-p-butyl 0.055 kg ha-1 10 DAS + hoeing 40 DAS and fenoxaprop-p-ethyl 0.075 kg ha-110 DAS + hoeing 40 DAS. The highest amount of total N, P and K (112.61, 25.31 and 76.90 kg ha-1, respectively) was removed by mustard in weed free treatment followed by two hand weeding while the lowest N, P and K with the values of 70.11, 16.05 and 51.86 kg ha-1, respectively was removed by weedy check followed by isoproturon 0.75 kg ha ha-1. Among the weed management practices, the total uptake of N, P and K by weeds was found significantly less in all the weed management practices as compared to weedy check(5.87, 0.86 and 5.51 kg ha-1, respectively). The least nutrient depletion by weeds was registered with the hand weeding twice (0.52, 0.08 and 0.49 kg ha-1, respectively) followed by fluazifop-p-butyl 0.055 kg ha-1 10 DAS + hoeing 40 DAS and fenoxaprop-p-ethyl 0.075 kg ha-110 DAS + hoeing 40 DAS. Use of post emergence herbicides of ‘fop’ group such as fluazifop-p-butyl, quizalofop-p-ethyl, fenoxaprop-p-ethyl (which are mostly used in soybean and groundnut crop) in indian mustard found most effective in controlling grassy weeds in early stage whereas at latterly, one hoeing 40 DAS was found effective in controlling grassy as well as broad leaved weeds under irrigated conditions.