Impact of Herbicides on Yield of Direct-Seeded Rice and Microbial Population in Soil

Abstract

The herbicides used in direct-seeded rice (DSR) may be change the soil’s biotic balance, which could have an impact on the soil nutrient status, health, and productivity. During Kharif season 2016 and 2017, the field trials were carried out using 14 treatment combinations at Agriculture Research Farm of BAU, Sabour, Bihar, India. The findings showed that the various weed management methods used during both years had variable effects on the viable microbial community. The Bispyribac-Na 30 g a.i. ha-1 applied as a post-emergence (PoE) and Pendimethalin 1000 g. a.i. ha-1 applied as a pre-emergence (PE) significantly improved by 121.71% and 134.08% and 74.59% and 91.33% actinomycetes population after compared with weed free and weedy check, respectively at 90 days after sowing (DAS). Whereas highest grain (6667 kg ha-1) and straw (9777 kg ha-1) yields and harvest index (HI) (40.54%) was observed under Bispyribac-Na 15 g a.i. ha-1fb one hand weeding (1HW) at 40 days and was statistically at par with Azimsulfuron 17.5 g a.i. ha-1 fb 1HW at 40 DAS. The herbicides, viz. Almix, Ethoxysulfuron, Bispyribac-Na and Azimsulfuron as PoE and Pendimethalin and Pyrazosulfuron as PE were innocent for soil microbial populations at recommended dose.