Integrated management of weeds in raw jute

Abstract

Net profit from raw jute (jute and mesta together are called raw jute) cultivation is very poor owing to its high cost involvement (35-40% of the total cost of cultivation) in conventional manual weeding process. So far only post-emergence grass weed killing herbicides have been found to be successful in jute. After controlling grassy weeds, Cyperus rotundus and other broad-leaved weeds have become menace to these fibre crops which were effectively controlled adopting stale seedbed technique (herbicides applied on established weeds 10 days ahead of sowing jute and mesta) in Bararckpore, West Bengal. In stale seedbed method in jute,(cv ‘JRO-524’), glyphosate 2.46 kg SL/ha and 2,4-D 2 kg/ha in combination, and glyphosate 2.46 kg SL/ha and pyrazosulfuron-ethyl 60g/ha in combination followed by one hand weeding were found promising to control mixed weed flora in jute field. After two years’ cycle, these herbicide combinations reduced the Cyperus rotundus population by more than 80% over control and produced a mean of fibre yield of 28 to 3.04 t/ha and a maximum of 4.3 t jute fibre/ha in 2006-08. In mesta (cv. ‘HC-583’), in stale seedbed method, butacholor 0.75 kg/ha and 2, 4-D 2 kg/ha in combination followed by 2-HW produced a mean fibre yield of 2.65 t/ha with a maximum 3.2 t mesta fibre/ha in 2007-08 and kept the mesta field free from weed for a couple of weeks. Pretilachlor (0.5 kg/ha) and paraquat (0.48 kg SL/ha) in combination, when applied 10 days ahead of mesta sowing on established weeds, it controlled mixed weed flora and produced a mean mesta fibre yield of 2.68 t/ha. Quizalofop-ethyl 5% EC 60 g/ha and Dhanuvit 0.5 to 0.6 l/ha at 21 DAE and one hand weeding produced a mean mesta fibre yield of 2.76 t/ha with a maximum of 3.45 t fibre/ha in 2007-08. Except chlorimuron-ethyl, other herbicides did not affect the soil microbial flora in post harvest jute soil. All these methods produced mean fibre yields at par with two manual weedings.