Enhancing fibre yield and nutrient use efficiency of jute by managing diversified weed-flora in Eastern Himalayan foothill

Severe prevalence of multi-flush weed pressure reduces 60-70% fibre yield in jute. Increasing productivity and profitability of jute while decreasing production cost and control weeds population are emerging challenges for jute cultivation in eastern India. A study was conducted in 2017 and 2018 at the Uttar Banga Krishi Viswavidyalaya, Cooch Behar, India, to evaluate the efficacy of sole and sequential applications of pre-emergence (ipfencarbazone) and post-emergence (quizalofop ethyl and ethoxysulfuron) herbicides in comparison to hand weeding in jute. The sequential application of herbicides reduced weed density and biomass by 62-94% compared to non-treated plots, whereas, sole application of herbicides reduced weed density by 54-70% and weed biomass by 44-73%. All herbicide treatments and hand weeding significantly affected plant height, basal diameter, agronomic indices, nutrient acquisition and fibre yield of jute. The highest fibre yield was obtained in the weed-free plots (3.62-3.89 t ha^-1) and the plots treated with Ipfencarbazone followed by (fb) Quizalofop ethyl + ethoxysulfuron (3.24-3.43 t ha^-1) and Ipfencarbazone fb Ethoxysulfuron (3.02-3.12 t ha^-1). The lowest fibre yield (1.20-1.36 t ha-1) was achieved in the non-treated plots. Ipfencarbazone fb quizalofop ethyl + ethoxysulfuron recorded highest net return ( 75111- 79854 ha^-1) and benefit: cost ratio (2.68-2.99). The results suggest that ethoxysulfuron is the best broad-spectrum and economically effective herbicide when applied in combination with other effective pre and post-emergence herbicides with different modes of action, depending on the weed species present in the jute field.