Sequential application of pre- and post-emergence herbicides for the control of weeds in transplanted rice at Hirakud command areas of Odisha

Abstract

A field experiment was conducted during rainy (Kharif) seasons of 2018 and 2019 to assess the efficacy of the sequential application of pre- and post-emergence herbicides for managing complex weed flora in transplanted rice at Hirakud command areas of Odisha. The weed free maintained by hand weeding twice recorded the highest values of growth parameters and rice grain yield (6.4 t/ha). The weeds in weedy check caused 50% rice grain yield reduction. The sequential application of pre-emergence herbicide (PE) pretilachlor + bensulfuron-methyl (ready-mix) 660 g/ha followed by (fb) post-emergence application (PoE) of bispyribac-sodium 25 g/ha recorded the highest weed control efficiency (93%), rice grain yield (6.1 t/ha), net return (^ 63720/ha) and benefit cost ratio (2.4) with 72.8% reduction in weed biomass and 24.6% yield advantages over recommended practice of pendimethalin 1000 g/ha PE fb bispyribac-sodium 25 g/ha PoE.