Evaluation of the efficacy of sole and tank-mix herbicides in managing weeds in direct-seeded rice under rice - lentil cropping system

A field study was conducted during Kharif seasons of 2021 and 2022 at Regional Research Station (CSZ), BCKV, Kakdwip, West Bengal to evaluate the efficacy of herbicides against diverse weed flora in direct-seeded rice (DSR) under rice - lentil cropping system. Eleven treatments were tested in a randomized complete block design with three replications. Among herbicide treatments, the lowest weed density and biomass at 40 days after herbicide application (DAA), highest weed control efficiency and rice grain yield were recorded with post-emergence application (PoE), at 2–4 leaf stage of weeds or 18 DAS, of bispyribac-sodium 2% + 2,4-D sodium salt 54.3% SP (bispyribac-sodium + 2,4-D Na salt) (with adjuvant Adsee 611) at 30.0 + 814.5 g/ha. It was at par with bispyribac sodium + 2,4-D sodium salt (with adjuvant Adsee 611) PoE 25.0 + 678.75 g/ha. Maximum net return and benefit:cost ratio (1.76) was obtained with bispyribac-sodium + 2,4-D sodium salt (with adjuvant Adsee 611) PoE 25.0 + 678.75 g/ha, which can be recommended for effective management of weeds in DSR. The herbicides evaluated had no phytotoxic effect on DSR and on succeeding lentil crop.