Enhancing Rice Yield and Weed Management in Direct Seeded Rice Using Ammonium Sulfate as Adjuvant with Lower Dose of Early Postemergence Herbicides

Abstract

Over use of herbicides can results in weed resistance, health issues as well increase production cost. To address these issues, lower dose of herbicides with adjuvant would be a possible solution. A field experiment was conducted in 2016 to find out the sequential use of different herbicides with adjuvants towards improved rice production and weed management in direct seeded rice crop. Three early post emergence herbicides (Kelion 50 WG, Ryzelan 240 SC and Nominee 100 SC was applied at full or 75% of the full dose with and without adjuvants i.e. 2% solution of ammonium sulphate and alkyl ether sulphate at 14 days after sowing (DAS), followed by late post emergence herbicides i.e. Puma super (7.5 EW) and Sunstar (60 WG) at 28 DAS. Significant differences were recorded among herbicides with and without adjuvant for weed density, rice growth and yield. Results illustrated that application of 75% of Nominee 100 SC along adjuvant i.e. AS (2% v/v) substantially suppressed weed with weed dry weight at 40 and 60 DAS. It was found an efficient strategy for weed suppression, water absorption ratio, grain quality and optimal rice yield under direct seeded rice cultivation systems.